0001274737-22-000076 | 10-Q | XBRL Viewer

Borrowings

9 Months Ended

Sep. 30, 2022

2017 Term Loan

In September 2017, the Company executed a term loan agreement (the 2017 Term Loan) with Innovatus Life Sciences Lending Fund I, LP (Innovatus) and borrowed $20.0 million, $17.8 million of which was immediately used to repay the Company's existing loan with Capital Royalty Partners II L.P. and its affiliates. On December 7, 2018, the Company borrowed an additional $5.0 million under the 2017 Term Loan. The 2017 Term Loan was subsequently amended in November 2019 and November 2021. As of September 30, 2022, no additional amounts remain available to borrow under the 2017 Term Loan.

In November 2021, the Company executed the Second Amendment to the Loan and Security Agreement (the 2017 Loan Amendment). The interest rate on all borrowings under the 2017 Loan Amendment is 8.0%, of which 2.0% is paid in-kind in the form of additional term loans (PIK Loans) until December of 2024, after which interest accrues at an annual rate of 8.0%. The Company has estimated the effective interest rate of this loan to be approximately 8.5%. Accrued interest is due and payable monthly, unless the Company elects to pay paid-in-kind interest. The outstanding principal and accrued interest on the 2017 Loan Amendment will be repaid in twenty-four equal monthly installments commencing in December 2024. Upon repayment of the final installment under the 2017 Loan Amendment, the Company is required to pay an additional fee of $1.0 million. This obligation is being accreted into interest expense over the term of the 2017 Loan Amendment using the effective interest method. For each of the three months ended September 30, 2022 and 2021, the Company issued PIK Loans totaling $0.1 million. For each of the nine months ended September 30, 2022 and 2021, the Company issued PIK Loans totaling $0.4 million.

The 2017 Loan Amendment requires a prepayment premium of 3% of the aggregate outstanding principal. The prepayment premium decreases by 1% on November 1, 2022, 2023 and 2024.

The 2017 Loan Amendment is collateralized by a first priority security interest in substantially all of the Company's assets, including intellectual property. The affirmative covenants of the 2017 Loan Amendment require that the Company timely file taxes, maintain good standing and government compliance, maintain liability and other insurance, provide prompt notification of significant corporate events, and furnish audited financial statements within 150 days of fiscal year end without qualification as to the scope of the audit or as to going concern and without any other similar qualification.

The affirmative covenants require that the Company achieve a specified level of revenue, as measured quarterly on a rolling twelve-month basis, and commencing with the quarter ending December 31, 2022. The consequences of failing to achieve the performance covenant may be cured if, within sixty days of failing to achieve the performance covenant, the Company issues additional equity securities or subordinated debt with net proceeds sufficient to fund any cash flow deficiency generated from operations, as defined. The 2017 Loan Amendment requires that the Company maintain certain levels of minimum liquidity and maintains an unrestricted cash balance of $2.0 million.

The negative covenants provide, among other things, that without the prior consent of Innovatus subject to certain exceptions, the Company may not dispose of certain assets, engage in certain business combinations or

acquisitions, incur additional indebtedness or encumber any of the Company's property, pay dividends on the Company's capital stock or make prohibited investments. The 2017 Loan Amendment provides that an event of default will occur if, among other triggers, (i) the Company defaults in the payment of any amount payable under the agreement when due, (ii) there occurs any circumstance(s) that could reasonably be expected to result in a material adverse effect on the Company's business, operations or condition, or on the Company's ability to perform its obligations under the agreement, (iii) the Company becomes insolvent, (iv) the Company undergoes a change in control or (v) the Company breaches any negative covenants or certain affirmative covenants in the agreement or, subject to a cure period, otherwise neglects to perform or observe any material item in the agreement.

As of September 30, 2022, the Company was in compliance with all covenants of the 2017 Loan Amendment.

Upon an event of default in any of the 2017 Loan Amendment covenants, the repayment of the 2017 Loan Amendment may be accelerated, and the applicable interest rate will be increased by 4.0% until the default is cured. Although repayment of the 2017 Loan Amendment can be accelerated under certain circumstances, the Company believes acceleration of this loan is not probable as of the date of these condensed financial statements. Accordingly, the Company has reflected the amounts of the 2017 Loan Amendment due beyond twelve months of the balance sheet date as non-current.

Future Minimum Payments on the Outstanding Borrowings

As of September 30, 2022, future minimum aggregate payments, including interest, for outstanding borrowings under the 2017 Loan Amendment are as follows (in thousands):


2022 (remaining)	$	420
2023	1,686
2024	2,980
2025	16,152
2026	14,786
Total	36,024
Less:
Unamortized debt discount and issuance costs	(170)
Interest	(7,846)
Total borrowings, net of discounts and debt issuance costs	$	28,008

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

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+ Details

Other Financial Information - Prepaid Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Other Financial Information [Abstract]
Diagnostic testing supplies	$ 1,364	$ 1,091
Prepaid product royalties	42	49
Prepaid maintenance and insurance contracts	1,001	2,008
Other prepaid expenses and other current assets	310	490
Prepaid expenses and other current assets	$ 2,717	$ 3,638

Restatement of Previously Issued Financial Statements - Financial Statements (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						6 Months Ended	9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Condensed Balance Sheet
Accounts receivable, net	$ 10,639	$ 8,715					$ 8,715	$ 10,639		$ 9,654
Total current assets	82,060	88,164					88,164	82,060		112,734
Total assets	101,597	106,849					106,849	101,597		123,445
Accrued and other current liabilities	6,654	5,970					5,970	6,654		6,826
Total current liabilities	11,332	10,054					10,054	11,332		9,318
Total liabilities	45,411	44,025					44,025	45,411		38,509
Accumulated deficit	(241,173)	(233,077)					(233,077)	(241,173)		(208,140)
Total stockholders' equity	56,186	62,824	$ 76,156	$ 90,803	$ 96,380	$ 101,470	62,824	56,186	$ 90,803	84,936	$ 41,839
Total liabilities and stockholders' equity	101,597	106,849					106,849	101,597		$ 123,445
Condensed Statement of Operations
Revenue	14,726	7,606		12,251			18,000	32,726	35,610
Loss from operations	(7,817)	(14,064)		(6,504)			(23,743)	(31,560)	(17,813)
Net loss	$ (8,096)	$ (14,665)	(10,272)	$ (7,179)	(6,410)	(6,209)	$ (24,937)	$ (33,033)	$ (19,798)
Net loss per share, basic (in dollars per share)	$ (0.47)	$ (0.86)		$ (0.42)			$ (1.46)	$ (1.94)	$ (1.27)
Net loss per share, diluted (in dollars per share)	$ (0.47)	$ (0.86)		$ (0.42)			$ (1.46)	$ (1.94)	$ (1.27)
Condensed Statement of Cash Flows
Net loss	$ (8,096)	$ (14,665)	$ (10,272)	$ (7,179)	$ (6,410)	$ (6,209)	$ (24,937)	$ (33,033)	$ (19,798)
Accounts receivable, net							939	(985)	(300)
Accrued and other current liabilities							(751)	(121)	538
Net cash used in operating activities							(19,728)	$ (26,410)	$ (14,222)
As Originally Reported
Condensed Balance Sheet
Accounts receivable, net		9,590					9,590
Total current assets		89,039					89,039
Total assets		107,724					107,724
Accrued and other current liabilities		5,489					5,489
Total current liabilities		9,573					9,573
Total liabilities		43,544					43,544
Accumulated deficit		(231,721)					(231,721)
Total stockholders' equity		64,180					64,180
Total liabilities and stockholders' equity		107,724					107,724
Condensed Statement of Operations
Revenue		8,962					19,356
Loss from operations		(12,708)					(22,387)
Net loss		$ (13,309)					$ (23,581)
Net loss per share, basic (in dollars per share)		$ (0.78)					$ (1.39)
Net loss per share, diluted (in dollars per share)		$ (0.78)					$ (1.39)
Condensed Statement of Cash Flows
Net loss		$ (13,309)					$ (23,581)
Accounts receivable, net							64
Accrued and other current liabilities							(1,232)
Net cash used in operating activities							(19,728)
Adjustments
Condensed Balance Sheet
Accounts receivable, net		(875)					(875)
Total current assets		(875)					(875)
Total assets		(875)					(875)
Accrued and other current liabilities		481					481
Total current liabilities		481					481
Total liabilities		481					481
Accumulated deficit		(1,356)					(1,356)
Total stockholders' equity		(1,356)					(1,356)
Total liabilities and stockholders' equity		(875)					(875)
Condensed Statement of Operations
Revenue		(1,356)					(1,356)
Loss from operations		(1,356)					(1,356)
Net loss		$ (1,356)					$ (1,356)
Net loss per share, basic (in dollars per share)		$ (0.08)					$ (0.07)
Net loss per share, diluted (in dollars per share)		$ (0.08)					$ (0.07)
Condensed Statement of Cash Flows
Net loss		$ (1,356)					$ (1,356)
Accounts receivable, net							875
Accrued and other current liabilities							481
Net cash used in operating activities							$ 0

Unaudited Condensed Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Income Statement [Abstract]
Revenue	$ 14,726	$ 12,251	$ 32,726	$ 35,610
Operating expenses:
Costs of revenue	6,010	5,487	17,905	15,649
Selling, general and administrative expenses	14,151	11,528	39,206	32,739
Research and development expenses	2,382	1,740	7,175	5,035
Total operating expenses	22,543	18,755	64,286	53,423
Loss from operations	(7,817)	(6,504)	(31,560)	(17,813)
Interest expense	(618)	(678)	(1,822)	(1,986)
Other income, net	339	3	349	1
Net loss	$ (8,096)	$ (7,179)	$ (33,033)	$ (19,798)
Net loss per share, basic (in dollars per share)	$ (0.47)	$ (0.42)	$ (1.94)	$ (1.27)
Net loss per share, diluted (in dollars per share)	$ (0.47)	$ (0.42)	$ (1.94)	$ (1.27)
Weighted-average number of shares used to compute net loss per share, basic (in shares)	17,080,959	16,945,591	17,044,623	15,636,150
Weighted-average number of shares used to compute net loss per share, diluted (in shares)	17,080,959	16,945,591	17,044,623	15,636,150

Summary of Significant Accounting Policies - Securities (Details) - shares	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Class of Stock [Line Items]
Anti-dilutive securities excluded from computation (in shares)	3,052,363	2,883,395
Warrants to purchase common stock
Class of Stock [Line Items]
Anti-dilutive securities excluded from computation (in shares)	409,108	409,108
Common stock options
Class of Stock [Line Items]
Anti-dilutive securities excluded from computation (in shares)	1,820,555	2,067,057
Restricted stock units
Class of Stock [Line Items]
Anti-dilutive securities excluded from computation (in shares)	805,496	403,100
Employee stock purchase plan
Class of Stock [Line Items]
Anti-dilutive securities excluded from computation (in shares)	17,204	4,130

Cover - shares	9 Months Ended
Cover - shares	Sep. 30, 2022	Nov. 18, 2022
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2022
Document Transition Report	false
Entity File Number	001-39049
Entity Registrant Name	EXAGEN INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-0434866
Entity Address, Address Line One	1261 Liberty Way
Entity Address, City or Town	Vista,
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92081
City Area Code	(760)
Local Phone Number	560-1501
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	XGN
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		16,319,488
Entity Central Index Key	0001274737
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q3
Amendment Flag	false

Leases - Future Minimum Lease Payments Under Topic 840 (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Leases [Abstract]
2022	$ 1,337
2023	1,445
2024	1,489
2025	1,533
2026	1,584
Thereafter	539
Total minimum lease payments	$ 7,927

Stock Option Plan (Tables)

9 Months Ended

Sep. 30, 2022

Share-Based Payment Arrangement [Abstract]

Schedule of Stock Option Activity

Stock option activity under the Company's 2019 Plan is set forth below:


	Number of Options	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value (in thousands)
Outstanding, December 31, 2021	2,014,330	$	12.10	7.87	$	5,428
Granted	63,000	$	5.25
Exercised	(1,273)	$	0.33
Forfeited	(114,182)	$	13.74
Expired	(141,320)	$	13.79
Outstanding, September 30, 2022	1,820,555	$	11.63	7.19	$	1,150
Vested and expected to vest, September 30, 2022	1,820,555	$	11.63	7.19	$	1,150
Options exercisable, September 30, 2022	1,321,485	$	10.59	6.93	$	1,126

Schedule of Restricted Stock Unit Activity

Restricted stock unit activity under the Company's 2019 Plan is set forth below:


	Number of Shares	Weighted- Average Grant Date Fair Value		Aggregate Intrinsic Value (in thousands)
Outstanding, December 31, 2021	415,325	$	16.54	$	4,830
Awards granted	604,100	$	8.61
Awards released	(99,624)	$	16.62
Awards canceled	(114,305)	$	11.72
Outstanding, September 30, 2022	805,496	$	11.27	$	2,183

Schedule of Fair Value Assumptions, Stock Options

The fair value of employee stock options was estimated using the following assumptions to determine the fair value of stock options granted:


	Three Months Ended September 30,		Nine Months Ended September 30,
	2022	2021	2022	2021
Expected volatility	—%	86%	54%	83%-86%
Risk-free interest rate	—%	0.9%	3.4%	0.8%-1.1%
Dividend yield	—	—	—	—
Expected term (in years)	0	5.77	5.5	5.50-6.08

Schedule of Fair Value Assumptions, Employee Stock Purchase Plan

The following assumptions were used to calculate the stock-based compensation for each stock purchase right granted under the ESPP:


	Three Months Ended September 30,		Nine Months Ended September 30,
	2022	2021	2022	2021
Expected volatility	45%	45%	45%-57%	45%-60%
Risk-free interest rate	0.6%	0.1%	0.6%-3.3%	0.1%
Dividend yield	—	—	—	—
Expected term (in years)	0.50	0.50	0.50	0.50

Schedule of Non-cash Stock-based Compensation Expense

Total non-cash stock-based compensation expense recorded related to options granted, restricted stock units granted and stock purchase rights granted under the ESPP in the condensed statements of operations is as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Costs of revenue	$	56	$	64	$	159	$	136
Selling, general and administrative	1,085		1,115		3,406		2,955
Research and development	165		175		557		460
Total	$	1,306	$	1,354	$	4,122	$	3,551

Stock Option Plan - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 1,306	$ 1,354	$ 4,122	$ 3,551
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, unrecognized compensation cost	$ 3,500		$ 3,500
Stock options, cost not yet recognized, remaining weighted average vesting period			1 year 4 months 9 days
Granted (in shares)	0		63,000
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares that remain available for future awards (in shares)	413,425		413,425
Maximum employee payroll deduction percentage	20.00%		20.00%
Stock options, cost not yet recognized, remaining weighted average vesting period			4 months 28 days
Stock-based compensation expense	$ 100	$ 100	$ 100	$ 100
Unrecognized compensation cost related to stock purchase	100		100
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, unrecognized compensation cost	$ 7,700		$ 7,700
Stock options, cost not yet recognized, remaining weighted average vesting period			3 years 1 month 6 days
2019 Incentive Award Plan \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, expiration period			10 years
Stock options, vesting period			4 years
Shares that remain available for future awards (in shares)	1,528,877		1,528,877

Stock Option Plan - Fair Value Assumptions (Details)	3 Months Ended		9 Months Ended
Stock Option Plan - Fair Value Assumptions (Details)	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	0.00%	86.00%	54.00%
Expected volatility rate, minimum				83.00%
Expected volatility rate, maximum				86.00%
Risk-free interest rate	0.00%	0.90%	3.40%
Risk-free interest rate, minimum				0.80%
Risk-free interest rate, maximum				1.10%
Dividend yield	0.00%	0.00%	0.00%	0.00%
Expected term (in years)	0 years	5 years 9 months 7 days	5 years 6 months
Stock options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)				5 years 6 months
Stock options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)				6 years 29 days
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	45.00%	45.00%
Expected volatility rate, minimum			45.00%	45.00%
Expected volatility rate, maximum			57.00%	60.00%
Risk-free interest rate	0.60%	0.10%		0.10%
Risk-free interest rate, minimum			0.60%
Risk-free interest rate, maximum			3.30%
Dividend yield	0.00%	0.00%	0.00%	0.00%
Expected term (in years)	6 months	6 months	6 months	6 months

Summary of Significant Accounting Policies - Revenue by Major Payers (Details) - Customer Concentration Risk	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Medicare \| Revenue Benchmark
Disaggregation of Revenue [Line Items]
Percent of total revenue	62.00%	19.00%	37.00%	19.00%
Medicare \| Accounts Receivable, Net
Disaggregation of Revenue [Line Items]
Percent of total revenue			53.00%
Medicare Advantage \| Revenue Benchmark
Disaggregation of Revenue [Line Items]
Percent of total revenue	12.00%	13.00%	15.00%	13.00%
Blue Shield \| Revenue Benchmark
Disaggregation of Revenue [Line Items]
Percent of total revenue		12.00%		12.00%
Blue Shield \| Accounts Receivable, Net
Disaggregation of Revenue [Line Items]
Percent of total revenue					19.00%
United Healthcare \| Accounts Receivable, Net
Disaggregation of Revenue [Line Items]
Percent of total revenue					18.00%

Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2022

Equity [Abstract]

Schedule of Outstanding Warrants

The following equity classified warrants to purchase common stock were outstanding as of September 30, 2022:


	Shares	Exercise Price		Issuance date	Expiration date
Common stock warrants	237,169	$	1.84	January 19, 2016	January 19, 2026
Common stock warrants	67,086	$	1.84	March 31, 2016	March 31, 2026
Common stock warrants	131	$	1.84	April 1, 2016	April 1, 2026
Common stock warrants	83,778	$	14.32	September 7, 2017	September 7, 2024
Common stock warrants	20,944	$	14.32	December 7, 2018	December 7, 2025
Common stock warrants (Exchange Warrants)	804,951	$	0.001	June 22, 2021	None
	1,214,059

During the three and nine months ended September 30, 2022, no warrants to purchase common stock were exercised.

Borrowings (Tables)

9 Months Ended

Sep. 30, 2022

Debt Disclosure [Abstract]

Schedule of Future Minimum Aggregate Payments for Outstanding Borrowings

As of September 30, 2022, future minimum aggregate payments, including interest, for outstanding borrowings under the 2017 Loan Amendment are as follows (in thousands):


2022 (remaining)	$	420
2023	1,686
2024	2,980
2025	16,152
2026	14,786
Total	36,024
Less:
Unamortized debt discount and issuance costs	(170)
Interest	(7,846)
Total borrowings, net of discounts and debt issuance costs	$	28,008

Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2022

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Basis of Presentation and Use of Estimates

The accompanying interim condensed balance sheet as of September 30, 2022, the condensed statements of operations and the condensed statements of stockholders' equity for the three and nine months ended September 30, 2022 and 2021, cash flows for the nine months ended September 30, 2022 and 2021 and the

related footnote disclosures are unaudited and have been prepared in accordance with the rules and regulations of the Securities and Exchange Commission (SEC), and with accounting principles generally accepted in the United States (GAAP) applicable to interim financial statements. In management's opinion, the unaudited interim condensed financial statements have been prepared on the same basis as the audited financial statements and include all normal adjustments, necessary for the fair presentation of the Company's financial position as of September 30, 2022 and its results of operations for the three and nine month periods presented. The results for the nine months ended September 30, 2022 are not necessarily indicative of the results expected for the full fiscal year or any other interim period. The year-end condensed balance sheet data was derived from audited financial statements, but does not include all disclosures required by GAAP. These unaudited condensed financial statements should be read in conjunction with the Company’s audited financial statements for the year ended December 31, 2021, included in its Annual Report on Form 10-K filed with the SEC on March 22, 2022.

The preparation of the accompanying condensed financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities as of the date of the condensed financial statements, and the reported amounts of revenue and expenses during the reporting period. Actual results could materially differ from those estimates.

Significant estimates and assumptions made in the accompanying condensed financial statements include, but are not limited to revenue recognition, estimated incremental borrowing rate for the determination of the Company's operating lease right-of-use (ROU) assets, the recoverability of its long-lived assets (including goodwill) and net deferred tax assets (and related valuation allowance). The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could materially differ from those estimates.

Concentration of Credit Risk and Other Risk and Uncertainties

Financial instruments that potentially subject the Company to credit risk consist principally of cash, cash equivalents and accounts receivable. Substantially all the Company's cash and cash equivalents are held at one financial institution that management believes is of high credit quality. Such deposits may, at times, exceed federally insured limits.

Significant payors and customers are those which represent more than 10% of the Company's total revenue or accounts receivable balance at each respective balance sheet date. For each significant payor and customer, revenue as a percentage of total revenue and accounts receivable as a percentage of total accounts receivable are as follows:


	Revenue
	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021

Medicare	62	%	19	%	37	%	19	%
Medicare Advantage	12	%	13	%	15	%	13	%

Blue Shield	*		12	%	*		12	%



*						Less than 10%.


	Accounts Receivable, Net
	September 30, 2022		December 31, 2021

Medicare	53	%	*
Blue Shield	*		19	%
United Healthcare	*		18	%



*						Less than 10%.

For the three months ended September 30, 2022 and 2021, approximately 87% and 81%, respectively, of the Company's revenue was related to the AVISE® CTD test. For the nine months ended September 30, 2022 and 2021, approximately 84% and 81%, respectively, of the Company's revenue was related to the AVISE® CTD test.

The Company is dependent on key suppliers for certain laboratory materials. For the three months ended September 30, 2022 and 2021, approximately 97% and 95%, respectively, of the Company's diagnostic testing supplies were purchased from two suppliers. For each of the nine months ended September 30, 2022 and 2021, approximately 96% of the Company's diagnostic testing supplies were purchased from two suppliers. An interruption in the supply of these materials would impact the Company's ability to perform testing services.

Disaggregation of Revenue

The following table includes the Company's revenues as disaggregated by payor and customer category (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Revenue:
Healthcare insurers	$	3,216	$	6,910	$	14,259	$	20,318
Government	9,228		2,330		12,242		6,733
Client(1)	2,046		2,346		5,496		6,738
Other(2)	236		265		729		821
Janssen (SIMPONI®)	—		400		—		1,000
Total revenue	$	14,726	$	12,251	$	32,726	$	35,610

(1)Includes hospitals, other laboratories, etc.

(2)Includes patient self-pay.

Fair Value Measurements

The carrying value of the Company's cash and cash equivalents approximate fair value due to the short-term nature of these items. The estimated fair value of the Company's long-term borrowings are determined by Level 2 inputs and is based primarily on quoted market prices for the same or similar issues. The recorded value of the Company's long-term borrowings approximates the current fair value as the interest rate and other terms are that which are currently available to the Company.

Fair value is defined as the exchange price that would be received for an asset or an exit price paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs.

The fair value hierarchy defines a three-level valuation hierarchy for disclosure of fair value measurements as follows:

Level 1 - Unadjusted quoted prices in active markets for identical assets or liabilities;

Level 2 - Inputs other than quoted prices included within Level I that are observable, unadjusted quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the related assets or liabilities; and

Level 3 - Unobservable inputs that are supported by little or no market activity for the related assets or liabilities.

The categorization of a financial instrument within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement.

Cash, Cash Equivalents and Restricted Cash

The Company considers all highly-liquid investments purchased with a remaining maturity date upon acquisition of three months or less to be cash equivalents and are stated at cost, which approximates fair value.

In connection with it's corporate credit card program, the Company is required to maintain a certificate of deposit of $0.2 million and $0.1 million at September 30, 2022 and December 31, 2021, respectively, as collateral for amounts borrowed on the credit cards. The Company has classified the value of this certificate of deposit (including all interest earned thereon) within other assets in the accompanying balance sheets. The Company has the right to terminate the credit card program at any time. Upon termination of the credit card program and repayment of all outstanding balances owed, the Company may redeem the certificate of deposit (and all interest earned thereon).

Cash, cash equivalents and restricted cash consist of the following (in thousands):


	September 30, 2022		September 30, 2021		December 31, 2021
Cash and cash equivalents	$	68,704	$	106,766	$	99,442
Restricted cash	200		100		100
	$	68,904	$	106,866	$	99,542

Long-lived Assets

The Company’s long-lived assets are comprised principally of its property and equipment, finite lived intangible assets, and goodwill.

If the Company identifies a change in the circumstances related to its long-lived assets, such as property and equipment and intangible assets (other than goodwill), that indicates the carrying value of any such asset may not be recoverable, the Company will perform an impairment analysis. A long-lived asset (other than goodwill) is deemed to be impaired when the undiscounted cash flows expected to be generated by the asset (or asset group) are less than the asset’s carrying amount. Any required impairment loss would be measured as the amount by which the asset’s carrying value exceeds its fair value, and would be recorded as a reduction in the carrying value of the related asset and a charge to operating expense.

Goodwill is tested for impairment annually (during the fourth quarter) or more frequently if indicators of impairment exist. As the Company operates in a single operating segment and reporting unit, the Company first assesses qualitative factors to determine whether it is more likely than not that the fair value of the reporting unit is less than its carrying amount as a basis for determining whether it is necessary to perform a quantitative assessment. The Company considered the current and expected future economic and market conditions, the current market capitalization and forecasts. The Company determined that it was not more likely than not that the fair value of the reporting unit was less than the carrying value as of September 30, 2022. Therefore, an interim quantitative impairment test was not performed.

Revenue Recognition

Substantially all of the Company's revenue has been derived from sales of its testing products and is primarily comprised of a high volume of relatively low-dollar transactions. The Company primarily markets its testing products to rheumatologists and their physician assistants in the United States. The healthcare professionals who order the Company's testing products and to whom test results are reported are generally not responsible for payment for these products. The parties that pay for these services (each, payors) consist of healthcare insurers, government payors (primarily Medicare and Medicaid), client payors (i.e., hospitals, other laboratories, etc.), and patient self-pay. The Company's service is a single performance obligation that is completed upon the delivery of test results to the prescribing physician which triggers revenue recognition.

Payors are billed at the Company's list price. Net revenues recognized consist of amounts billed net of allowances for differences between amounts billed and the estimated consideration the Company expects to receive from such payors. The process for estimating revenues and the ultimate collection of accounts receivable involves significant judgment and estimation. The Company follows a standard process, which considers historical denial and collection

experience, insurance reimbursement policies and other factors, to estimate allowances and implicit price concessions, recording adjustments in the current period as changes in estimates occur. Further adjustments to the allowances, based on actual receipts, are recorded upon settlement. Included in revenues for the three months ended September 30, 2022 was a $3.7 million revenue increase for tests delivered in a prior period due to the reassessment of the constraint on variable consideration and a $1.9 million net revenue decrease associated with other changes in estimated variable consideration related to performance obligations satisfied in previous periods. Included in revenues for the three months ended September 30, 2021 was a $0.1 million net revenue increase, associated with changes in estimated variable consideration related to performance obligations satisfied in previous periods. Included in revenues for the nine months ended September 30, 2022 and 2021 was a net revenue decrease of $2.5 million and a net revenue increase of $0.2 million, respectively, associated with changes in estimated variable consideration related to performance obligations satisfied in previous periods. The transaction price is estimated using an expected value method on a portfolio basis.

Variable consideration is included in the transaction price only to the extent it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainties with respect to the amount are resolved. The Company's portfolios are grouped per payor (i.e. each individual third-party insurance, Medicare, client payors, patient self-pay, etc.) and per test. Consideration may be constrained and excluded from the transaction price in situations where there is no contractually agreed upon reimbursement coverage or in absence of a predictable pattern and history of collectability with a payor. Accordingly, in such situations revenues are recognized on the basis of actual cash collections. Additionally, from time to time, the Company may issue refunds to payors for overpayments or amounts billed in error. Any refunds are accounted for as reductions in revenues in the statement of operations as an element of variable consideration. The estimated expected refunds are accrued as a liability on the Company’s balance sheet.

Collection of the Company's net revenues from payors is normally a function of providing complete and correct billing information to the healthcare insurers and generally occurs within 30 to 90 days of billing. Contracts do not contain significant financing components based on the typical period of time between performance of services and collection of consideration.

Janssen Promotion Agreement

In December 2018, the Company entered into a co-promotion agreement (as amended from time to time, the Janssen Agreement) with Janssen Biotech, Inc. (Janssen) to co-promote SIMPONI® in the United States. In August 2021, the Company and Janssen mutually agreed to terminate the Janssen Agreement effective on August 31, 2021.

Pursuant to the Janssen Agreement, as amended, the Company was responsible for the costs associated with its sales force over the course of such co-promotion. Janssen was responsible for all other aspects of the commercialization of SIMPONI® under the Janssen Agreement. In exchange for the Company's sales and co-promotional services, the Company was entitled to a quarterly tiered promotion fee based on the incremental increase in total prescribed units of SIMPONI® for that quarter over a predetermined baseline. The Company's obligations relating to sales and co-promotion services for SIMPONI® were a series of single performance obligations since Janssen simultaneously received and consumed benefits provided by the Company's sales and co-promotional services. The method for measuring progress towards satisfying the performance obligations was based on prescribed units in excess of the contractual baseline at the contractual rate earned per unit. The Company recognized no co-promotion revenue and $0.4 million during the three months ended September 30, 2022 and 2021, respectively. The Company recognized no co-promotion revenue and $1.0 million during the nine months ended September 30, 2022 and 2021, respectively. The related expenses for marketing SIMPONI® are included in selling, general and administrative expenses and are expensed as incurred.

Upon the termination of the Janssen Agreement on August 31, 2021, the Company became entitled to receive an aggregate of $0.6 million in consideration, which was earned in the year ended December 31, 2021. Pursuant to the terms of the termination, the Company was restricted until May 31, 2022 from promoting any other biologic or Janus kinase inhibitor used for the treatment of indications covered by the Janssen Agreement without first obtaining Janssen's written consent. The restriction no longer applies.

Leases

The Company categorizes leases at their commencement as either operating or finance leases. Effective January 1, 2022 upon the adoption of Accounting Standards Codification (ASC) 842, the Company recognizes operating lease

ROU assets and operating lease liabilities for each lease arrangement identified. Lease liabilities are recorded at the present value of future lease payments discounted using the Company's incremental borrowing rate for the lease established at the commencement date and ROU assets are measured at the amount of the lease liability plus any initial direct costs, less any lease incentives received before commencement. Lease expense is recognized as a single lease cost over the lease term on a straight-line basis. The Company has elected not to apply the recognition requirements to short-term leases and not to separate non-lease components from lease components for its leases. See Note 5 for details on the Company's leases.

Research and Development

Costs associated with research and development activities are expensed as incurred and include, but are not limited to, personnel-related expenses, including stock-based compensation expense, materials, laboratory supplies, consulting costs, costs associated with setting up and conducting clinical studies and allocated overhead including rent and utilities.

Advertising and Marketing Costs

Costs associated with advertising and marketing activities are expensed as incurred. Total advertising and marketing costs were approximately $1.3 million and $0.6 million for the three months ended September 30, 2022 and 2021, respectively, and $2.2 million and $1.3 million for the nine months ended September 30, 2022 and 2021, respectively, and are included in selling, general and administrative expenses in the accompanying condensed statements of operations.

Shipping and Handling Costs

Costs incurred for shipping and handling are included in costs of revenue in the accompanying condensed statements of operations and totaled approximately $0.7 million and $0.6 million for the three months ended September 30, 2022 and 2021, respectively, and $2.1 million and $1.6 million for the nine months ended September 30, 2022 and 2021, respectively.

Stock-Based Compensation

The Company recognizes compensation expense for all stock-based awards to employees and directors based on the grant-date estimated fair values over the requisite service period of the awards (usually the vesting period) on a straight-line basis. The fair value of stock options and purchases under the Company's 2019 Employee Stock Purchase Plan (ESPP) rights are determined using the Black-Scholes-Merton (BSM) option pricing model, which requires management to make certain assumptions regarding a number of complex and subjective variables. Equity award forfeitures are recorded as they occur.

The fair value of each restricted stock unit is determined on the grant date using the closing price of the Company's common stock on the grant date and generally vest from the grant date in four equal annual installments subject to the holder's continued service with the Company. The Company issues new shares to satisfy restricted stock units upon vesting.

Comprehensive Loss

Comprehensive loss is defined as a change in equity of a business enterprise during a period, resulting from transactions from nonowner sources. There have been no items qualifying as other comprehensive loss and, therefore, for all periods presented, the Company's comprehensive loss was the same as its reported net loss.

Net Loss Per Share

Basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period. Diluted net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of common stock equivalents outstanding for the period determined using the treasury-stock and if-converted methods. The weighted-average number of shares in 2022 and 2021 used to compute basic and diluted shares includes shares issuable upon the exercise of pre-funded warrants at a nominal price. Potentially dilutive common stock equivalents are comprised of warrants for the purchase of common

stock, options, restricted stock units outstanding under the Company's 2019 Incentive Award Plan (the 2019 Plan) and shares of the Company's common stock pursuant to the ESPP. For the three and nine months ended September 30, 2022 and 2021, there is no difference in the number of shares used to calculate basic and diluted shares outstanding, as the inclusion of the potentially dilutive securities would be antidilutive.

Potentially dilutive securities not included in the calculation of diluted net loss per share because to do so would be anti-dilutive are as follows (in common stock equivalent shares):


	September 30,
	2022	2021


Warrants to purchase common stock	409,108	409,108
Common stock options	1,820,555	2,067,057
Restricted stock units	805,496	403,100
Employee stock purchase plan	17,204	4,130
Total	3,052,363	2,883,395

Segment Reporting

Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. The Company views its operations as, and manages its business in, one operating segment.

Recent Accounting Pronouncements Not Yet Adopted

From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (FASB), or other standard setting bodies and adopted by the Company as of the specified effective date. Under the Jumpstart Our Business Startups Act of 2012 (JOBS Act), the Company meets the definition of an emerging growth company (EGC). The Company has elected to use the extended transition period for complying with new or revised accounting standards pursuant to Section 107(b) of the JOBS Act. Unless otherwise discussed, the impact of recently issued standards that are not yet effective will not have a material impact on the Company's financial position or results of operations upon adoption.

In June 2016, the FASB issued Accounting Standards Update (ASU) 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which requires the measurement of expected credit losses for financial instruments carried at amortized cost, such as accounts receivable, held at the reporting date based on historical experience, current conditions and reasonable forecasts. The main objective of this ASU is to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. In November 2018, the FASB issued ASU 2018-19, Codification Improvements to Topic 326, Financing Instruments-Credit Losses, which included an amendment of the effective date for nonpublic entities. For non-EGCs, ASU 2016-13 is effective for fiscal years beginning after December 15, 2019. For EGCs, the standard was to be effective for fiscal years beginning after December 15, 2021. However, in November 2019, the FASB issued ASU 2019-10, which included a one-year deferral of the effective date of ASU 2016-13 for certain entities. As a result, the ASU 2016-13 is now effective for EGCs for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. The Company is currently evaluating the impact of Topic 326 on its condensed financial statements.

Recently Adopted Accounting Standards

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842). The new topic supersedes Topic 840, Leases, and increases transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and requires disclosures of key information about leasing arrangements. In July 2018, the FASB issued ASU 2018-10, Codification Improvements to Topic 842, which provides narrow amendments to clarify how to apply certain aspects of the new lease standard, and ASU 2018-11, Leases: Targeted Improvements, which was issued to provide relief to companies from restating comparative periods. Pursuant to this ASU, in the period of adoption the Company will not restate comparative periods presented in its condensed

financial statements. On January 1, 2022, the Company adopted ASU 2016-12 using the modified retrospective transition method. Periods prior to January 1, 2022 have not been restated for the adoption of ASC 842 and continue to reflect the accounting treatment of leases in accordance with the prior lease accounting guidance, ASC 840, Leases. The Company adopted the new lease standard using a cumulative effect to accumulated deficit and there was no impact to accumulated deficit upon adoption. The Company elected the package of practical expedients, which among other things allowed the Company to carry forward its historical lease classification. As part of the adoption, the Company recorded operating lease liabilities of $6.4 million, operating lease ROU assets of $5.9 million, adjusted for deferred rent and lease incentive obligations of $0.5 million previously included in other non-current liabilities and accrued and other current liabilities, pertaining to its office and laboratory space operating leases. See Note 5 for details on the Company's leases.

Unaudited Condensed Statements of Stockholders' Equity (Parenthetical) $ in Thousands	Mar. 31, 2021 USD ($)
Statement of Financial Position [Abstract]
Stock issuance costs	$ 4,435

Commitment and Contingencies (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended		9 Months Ended
	Nov. 30, 2021	May 31, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Loss Contingencies [Line Items]
Purchase obligation, due in year one							$ 6.9
Purchase obligation, to be paid remainder of fiscal year							$ 6.0
Annual increase in purchase commitments							15.00%
Licensing Agreements
Loss Contingencies [Line Items]
Purchase obligation, due in year one	$ 0.1
Period for royalties to begin	18 months
Licensing Agreements \| Minimum
Loss Contingencies [Line Items]
Royalty obligation, percent of net sales			1.50%		1.50%
Licensing Agreements \| Maximum
Loss Contingencies [Line Items]
Royalty obligation, percent of net sales			7.00%		7.00%
AHN Collaboration
Loss Contingencies [Line Items]
Collaboration agreement, collaboration expenses			$ 0.1	$ 0.1	$ 0.3	$ 0.2
Prometheus Laboratories
Loss Contingencies [Line Items]
Future minimum royalty commitment			1.2		1.2
Advance royalties payment			$ 0.1		$ 0.1
Prometheus Laboratories \| Minimum
Loss Contingencies [Line Items]
Royalty obligation, percent of net sales			2.50%		2.50%
Allegheny Health Network Research Institute
Loss Contingencies [Line Items]
Collaboration fee		$ 0.4
Allegheny Health Network Research Institute \| Licensing Agreements
Loss Contingencies [Line Items]
Initial license fee		$ 0.4
Queen Mary University \| Licensing Agreements
Loss Contingencies [Line Items]
Initial license fee	$ 0.4

Leases - Costs Associated with the Company's Leases (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2022
Leases [Abstract]
Operating lease cost	$ 384	$ 1,156
Amortization of lease assets	174	487
Interest on finance lease liabilities	20	60
Total lease cost	578	1,703
Variable lease cost	$ 41	$ 124

Restatement of Previously Issued Financial Statements

9 Months Ended

Sep. 30, 2022

Accounting Changes and Error Corrections [Abstract]

Restatement of Previously Issued Financial Statements

The Company has restated previously issued financial statements and related disclosures as of and for the three and six months ended June 30, 2022 included in our Quarterly Report on Form 10-Q, filed with the Securities and Exchange Commission (the SEC) on August 4, 2022 (the Original Quarterly Report), in order to correct misstatements resulting from erroneous and duplicate billings included in revenue. The applicable Notes to Condensed Financial Statements were also updated to reflect the restatement.

Impact of Restatement

In November 2022 management determined that the Company made certain errors in revenue resulting from erroneous and duplicate billings related to changes in billing practices. The errors were due to the inadequate design and implementation and precision of internal controls and procedures to evaluate and monitor the accounting for revenue recognition. As a result, the Company determined that there were material errors in the financial statements that required a restatement of the financial statements for the three and six months ended June 30, 2022 in the Original Quarterly Report. The effect of these errors was a $1.4 million overstatement of revenue for the three and six months ended June 30, 2022; in addition to, a $0.9 million overstatement of accounts receivable and a $0.5 million understatement of other liabilities as of June 30, 2022.

The following tables reflect the impact of the restatement adjustments to the specific line items presented in our previously reported financial statements for the periods indicated. The amounts originally reported were derived from the Original Quarterly Report (in thousands, except per share amounts):


Condensed Balance Sheet	June 30, 2022
	As Originally Reported		Adjustments		As Restated
Assets
Accounts receivable, net	$	9,590	$	(875)	$	8,715
Total current assets	89,039		(875)		88,164
Total assets	107,724		(875)		106,849

Liabilities and Stockholders' Equity
Accrued and other current liabilities	5,489		481		5,970
Total current liabilities	9,573		481		10,054
Total liabilities	43,544		481		44,025
Accumulated deficit	(231,721)		(1,356)		(233,077)
Total stockholders' equity	64,180		(1,356)		62,824
Total liabilities and stockholders' equity	107,724		(875)		106,849


Condensed Statement of Operations	Three Months Ended June 30, 2022
	As Originally Reported		Adjustments		As Restated
Revenue	$	8,962	$	(1,356)	$	7,606
Loss from operations	(12,708)		(1,356)		(14,064)
Net loss	(13,309)		(1,356)		(14,665)
Net loss per share, basic and diluted	(0.78)		(0.08)		(0.86)


Condensed Statement of Operations	Six Months Ended June 30, 2022
	As Originally Reported		Adjustments		As Restated
Revenue	$	19,356	$	(1,356)	$	18,000
Loss from operations	(22,387)		(1,356)		(23,743)
Net loss	(23,581)		(1,356)		(24,937)
Net loss per share, basic and diluted	(1.39)		(0.07)		(1.46)


Condensed Statement of Cash Flows	Six Months Ended June 30, 2022
	As Originally Reported		Adjustments		As Restated
Cash flows from operating activities:
Net loss	$	(23,581)	$	(1,356)	$	(24,937)
Changes in assets and liabilities:
Accounts receivable, net.	64		875		939
Accrued and other current liabilities	(1,232)		481		(751)
Net cash used in operating activities	(19,728)		—		(19,728)

Other Financial Information (Tables)

9 Months Ended

Sep. 30, 2022

Other Financial Information [Abstract]

Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consist of the following (in thousands):


	September 30, 2022		December 31, 2021
Diagnostic testing supplies	$	1,364	$	1,091
Prepaid product royalties	42		49
Prepaid maintenance and insurance contracts	1,001		2,008
Other prepaid expenses and other current assets	310		490
Prepaid expenses and other current assets	$	2,717	$	3,638

Property and Equipment

Property and equipment, net consist of the following (in thousands):


	September 30, 2022		December 31, 2021
Furniture and fixtures	$	98	$	83
Laboratory equipment	5,488		4,361
Computer equipment and software	1,461		1,206
Leasehold improvements	3,230		1,151
Construction in progress	2,961		1,855
Total property and equipment	13,238		8,656
Less: accumulated depreciation and amortization	(4,907)		(3,884)
Property and equipment, net	$	8,331	$	4,772

Accrued and Other Current Liabilities

Accrued and other current liabilities consist of the following (in thousands):


	September 30, 2022		December 31, 2021
Accrued payroll and related expenses	$	3,353	$	4,048
Accrued interest	136		139
Accrued purchases of goods and services	1,227		510
Accrued royalties	69		180
Accrued clinical study activity	165		254
Finance lease obligations, current portion	730		587
Refund liability	445		—
Other accrued liabilities	529		1,108
Accrued and other current liabilities	$	6,654	$	6,826

Other Financial Information - Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 13,238	$ 8,656
Less: accumulated depreciation and amortization	(4,907)	(3,884)
Property and equipment, net	8,331	4,772
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Total property and equipment	98	83
Laboratory equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	5,488	4,361
Computer equipment and software
Property, Plant and Equipment [Line Items]
Total property and equipment	1,461	1,206
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	3,230	1,151
Construction in progress
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 2,961	$ 1,855

Fair Value Measurements (Details) - Recurring - Money market funds, included in cash and cash equivalents - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Assets:
Money market funds, included in cash and cash equivalents	$ 35,328	$ 95,761
Level 1
Assets:
Money market funds, included in cash and cash equivalents	35,328	95,761
Level 2
Assets:
Money market funds, included in cash and cash equivalents	0	0
Level 3
Assets:
Money market funds, included in cash and cash equivalents	$ 0	$ 0

Restatement of Previously Issued Financial Statements (Tables)

9 Months Ended

Sep. 30, 2022

Accounting Changes and Error Corrections [Abstract]

Schedule of Correction of Immaterial Misstatements


Condensed Balance Sheet	June 30, 2022
	As Originally Reported		Adjustments		As Restated
Assets
Accounts receivable, net	$	9,590	$	(875)	$	8,715
Total current assets	89,039		(875)		88,164
Total assets	107,724		(875)		106,849

Liabilities and Stockholders' Equity
Accrued and other current liabilities	5,489		481		5,970
Total current liabilities	9,573		481		10,054
Total liabilities	43,544		481		44,025
Accumulated deficit	(231,721)		(1,356)		(233,077)
Total stockholders' equity	64,180		(1,356)		62,824
Total liabilities and stockholders' equity	107,724		(875)		106,849


Condensed Statement of Operations	Three Months Ended June 30, 2022
	As Originally Reported		Adjustments		As Restated
Revenue	$	8,962	$	(1,356)	$	7,606
Loss from operations	(12,708)		(1,356)		(14,064)
Net loss	(13,309)		(1,356)		(14,665)
Net loss per share, basic and diluted	(0.78)		(0.08)		(0.86)


Condensed Statement of Operations	Six Months Ended June 30, 2022
	As Originally Reported		Adjustments		As Restated
Revenue	$	19,356	$	(1,356)	$	18,000
Loss from operations	(22,387)		(1,356)		(23,743)
Net loss	(23,581)		(1,356)		(24,937)
Net loss per share, basic and diluted	(1.39)		(0.07)		(1.46)


Condensed Statement of Cash Flows	Six Months Ended June 30, 2022
	As Originally Reported		Adjustments		As Restated
Cash flows from operating activities:
Net loss	$	(23,581)	$	(1,356)	$	(24,937)
Changes in assets and liabilities:
Accounts receivable, net.	64		875		939
Accrued and other current liabilities	(1,232)		481		(751)
Net cash used in operating activities	(19,728)		—		(19,728)

Subsequent Events	9 Months Ended
Subsequent Events	Sep. 30, 2022
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsIn October 2022, in connection with the appointment of its new Chief Executive Officer, the Company granted 350,000 restricted stock units which will vest in equal annual installments over four years.

Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2022
Accounting Policies [Abstract]
Concentration of Credit Risk and Other Risk and Uncertainties	Concentration of Credit Risk and Other Risk and Uncertainties Financial instruments that potentially subject the Company to credit risk consist principally of cash, cash equivalents and accounts receivable. Substantially all the Company's cash and cash equivalents are held at one financial institution that management believes is of high credit quality. Such deposits may, at times, exceed federally insured limits.
Fair Value Measurements	Fair Value Measurements The carrying value of the Company's cash and cash equivalents approximate fair value due to the short-term nature of these items. The estimated fair value of the Company's long-term borrowings are determined by Level 2 inputs and is based primarily on quoted market prices for the same or similar issues. The recorded value of the Company's long-term borrowings approximates the current fair value as the interest rate and other terms are that which are currently available to the Company. Fair value is defined as the exchange price that would be received for an asset or an exit price paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The fair value hierarchy defines a three-level valuation hierarchy for disclosure of fair value measurements as follows: Level 1 - Unadjusted quoted prices in active markets for identical assets or liabilities; Level 2 - Inputs other than quoted prices included within Level I that are observable, unadjusted quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the related assets or liabilities; and Level 3 - Unobservable inputs that are supported by little or no market activity for the related assets or liabilities. The categorization of a financial instrument within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement.
Cash, Cash Equivalents and Restricted Cash	Cash, Cash Equivalents and Restricted Cash The Company considers all highly-liquid investments purchased with a remaining maturity date upon acquisition of three months or less to be cash equivalents and are stated at cost, which approximates fair value.
Long-lived Assets	Long-lived Assets The Company’s long-lived assets are comprised principally of its property and equipment, finite lived intangible assets, and goodwill. If the Company identifies a change in the circumstances related to its long-lived assets, such as property and equipment and intangible assets (other than goodwill), that indicates the carrying value of any such asset may not be recoverable, the Company will perform an impairment analysis. A long-lived asset (other than goodwill) is deemed to be impaired when the undiscounted cash flows expected to be generated by the asset (or asset group) are less than the asset’s carrying amount. Any required impairment loss would be measured as the amount by which the asset’s carrying value exceeds its fair value, and would be recorded as a reduction in the carrying value of the related asset and a charge to operating expense. Goodwill is tested for impairment annually (during the fourth quarter) or more frequently if indicators of impairment exist. As the Company operates in a single operating segment and reporting unit, the Company first assesses qualitative factors to determine whether it is more likely than not that the fair value of the reporting unit is less than its carrying amount as a basis for determining whether it is necessary to perform a quantitative assessment. The Company considered the current and expected future economic and market conditions, the current market capitalization and forecasts. The Company determined that it was not more likely than not that the fair value of the reporting unit was less than the carrying value as of September 30, 2022. Therefore, an interim quantitative impairment test was not performed.
Revenue Recognition	Revenue Recognition Substantially all of the Company's revenue has been derived from sales of its testing products and is primarily comprised of a high volume of relatively low-dollar transactions. The Company primarily markets its testing products to rheumatologists and their physician assistants in the United States. The healthcare professionals who order the Company's testing products and to whom test results are reported are generally not responsible for payment for these products. The parties that pay for these services (each, payors) consist of healthcare insurers, government payors (primarily Medicare and Medicaid), client payors (i.e., hospitals, other laboratories, etc.), and patient self-pay. The Company's service is a single performance obligation that is completed upon the delivery of test results to the prescribing physician which triggers revenue recognition. Payors are billed at the Company's list price. Net revenues recognized consist of amounts billed net of allowances for differences between amounts billed and the estimated consideration the Company expects to receive from such payors. The process for estimating revenues and the ultimate collection of accounts receivable involves significant judgment and estimation. The Company follows a standard process, which considers historical denial and collection experience, insurance reimbursement policies and other factors, to estimate allowances and implicit price concessions, recording adjustments in the current period as changes in estimates occur. Further adjustments to the allowances, based on actual receipts, are recorded upon settlement. Included in revenues for the three months ended September 30, 2022 was a $3.7 million revenue increase for tests delivered in a prior period due to the reassessment of the constraint on variable consideration and a $1.9 million net revenue decrease associated with other changes in estimated variable consideration related to performance obligations satisfied in previous periods. Included in revenues for the three months ended September 30, 2021 was a $0.1 million net revenue increase, associated with changes in estimated variable consideration related to performance obligations satisfied in previous periods. Included in revenues for the nine months ended September 30, 2022 and 2021 was a net revenue decrease of $2.5 million and a net revenue increase of $0.2 million, respectively, associated with changes in estimated variable consideration related to performance obligations satisfied in previous periods. The transaction price is estimated using an expected value method on a portfolio basis. Variable consideration is included in the transaction price only to the extent it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainties with respect to the amount are resolved. The Company's portfolios are grouped per payor (i.e. each individual third-party insurance, Medicare, client payors, patient self-pay, etc.) and per test. Consideration may be constrained and excluded from the transaction price in situations where there is no contractually agreed upon reimbursement coverage or in absence of a predictable pattern and history of collectability with a payor. Accordingly, in such situations revenues are recognized on the basis of actual cash collections. Additionally, from time to time, the Company may issue refunds to payors for overpayments or amounts billed in error. Any refunds are accounted for as reductions in revenues in the statement of operations as an element of variable consideration. The estimated expected refunds are accrued as a liability on the Company’s balance sheet. Collection of the Company's net revenues from payors is normally a function of providing complete and correct billing information to the healthcare insurers and generally occurs within 30 to 90 days of billing. Contracts do not contain significant financing components based on the typical period of time between performance of services and collection of consideration.
Leases	Leases The Company categorizes leases at their commencement as either operating or finance leases. Effective January 1, 2022 upon the adoption of Accounting Standards Codification (ASC) 842, the Company recognizes operating lease ROU assets and operating lease liabilities for each lease arrangement identified. Lease liabilities are recorded at the present value of future lease payments discounted using the Company's incremental borrowing rate for the lease established at the commencement date and ROU assets are measured at the amount of the lease liability plus any initial direct costs, less any lease incentives received before commencement. Lease expense is recognized as a single lease cost over the lease term on a straight-line basis. The Company has elected not to apply the recognition requirements to short-term leases and not to separate non-lease components from lease components for its leases. See Note 5 for details on the Company's leases.
Research and Development	Research and Development Costs associated with research and development activities are expensed as incurred and include, but are not limited to, personnel-related expenses, including stock-based compensation expense, materials, laboratory supplies, consulting costs, costs associated with setting up and conducting clinical studies and allocated overhead including rent and utilities.
Advertising and Marketing Costs	Advertising and Marketing Costs Costs associated with advertising and marketing activities are expensed as incurred. Total advertising and marketing costs were approximately $1.3 million and $0.6 million for the three months ended September 30, 2022 and 2021, respectively, and $2.2 million and $1.3 million for the nine months ended September 30, 2022 and 2021, respectively, and are included in selling, general and administrative expenses in the accompanying condensed statements of operations.
Shipping and Handling Costs	Shipping and Handling Costs Costs incurred for shipping and handling are included in costs of revenue in the accompanying condensed statements of operations and totaled approximately $0.7 million and $0.6 million for the three months ended September 30, 2022 and 2021, respectively, and $2.1 million and $1.6 million for the nine months ended September 30, 2022 and 2021, respectively.
Stock-Based Compensation	Stock-Based Compensation The Company recognizes compensation expense for all stock-based awards to employees and directors based on the grant-date estimated fair values over the requisite service period of the awards (usually the vesting period) on a straight-line basis. The fair value of stock options and purchases under the Company's 2019 Employee Stock Purchase Plan (ESPP) rights are determined using the Black-Scholes-Merton (BSM) option pricing model, which requires management to make certain assumptions regarding a number of complex and subjective variables. Equity award forfeitures are recorded as they occur. The fair value of each restricted stock unit is determined on the grant date using the closing price of the Company's common stock on the grant date and generally vest from the grant date in four equal annual installments subject to the holder's continued service with the Company. The Company issues new shares to satisfy restricted stock units upon vesting.
Comprehensive Loss	Comprehensive Loss Comprehensive loss is defined as a change in equity of a business enterprise during a period, resulting from transactions from nonowner sources. There have been no items qualifying as other comprehensive loss and, therefore, for all periods presented, the Company's comprehensive loss was the same as its reported net loss.
Net Loss Per Share	Net Loss Per Share Basic net loss per share attributable to common stockholders is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period. Diluted net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of common stock equivalents outstanding for the period determined using the treasury-stock and if-converted methods. The weighted-average number of shares in 2022 and 2021 used to compute basic and diluted shares includes shares issuable upon the exercise of pre-funded warrants at a nominal price. Potentially dilutive common stock equivalents are comprised of warrants for the purchase of common stock, options, restricted stock units outstanding under the Company's 2019 Incentive Award Plan (the 2019 Plan) and shares of the Company's common stock pursuant to the ESPP. For the three and nine months ended September 30, 2022 and 2021, there is no difference in the number of shares used to calculate basic and diluted shares outstanding, as the inclusion of the potentially dilutive securities would be antidilutive.
Segment Reporting	Segment Reporting Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. The Company views its operations as, and manages its business in, one operating segment.
Recent Accounting Pronouncements Not Yet Adopted, Recently Adopted Accounting Standards	Recent Accounting Pronouncements Not Yet Adopted From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (FASB), or other standard setting bodies and adopted by the Company as of the specified effective date. Under the Jumpstart Our Business Startups Act of 2012 (JOBS Act), the Company meets the definition of an emerging growth company (EGC). The Company has elected to use the extended transition period for complying with new or revised accounting standards pursuant to Section 107(b) of the JOBS Act. Unless otherwise discussed, the impact of recently issued standards that are not yet effective will not have a material impact on the Company's financial position or results of operations upon adoption. In June 2016, the FASB issued Accounting Standards Update (ASU) 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which requires the measurement of expected credit losses for financial instruments carried at amortized cost, such as accounts receivable, held at the reporting date based on historical experience, current conditions and reasonable forecasts. The main objective of this ASU is to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. In November 2018, the FASB issued ASU 2018-19, Codification Improvements to Topic 326, Financing Instruments-Credit Losses, which included an amendment of the effective date for nonpublic entities. For non-EGCs, ASU 2016-13 is effective for fiscal years beginning after December 15, 2019. For EGCs, the standard was to be effective for fiscal years beginning after December 15, 2021. However, in November 2019, the FASB issued ASU 2019-10, which included a one-year deferral of the effective date of ASU 2016-13 for certain entities. As a result, the ASU 2016-13 is now effective for EGCs for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. The Company is currently evaluating the impact of Topic 326 on its condensed financial statements. Recently Adopted Accounting Standards In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842). The new topic supersedes Topic 840, Leases, and increases transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and requires disclosures of key information about leasing arrangements. In July 2018, the FASB issued ASU 2018-10, Codification Improvements to Topic 842, which provides narrow amendments to clarify how to apply certain aspects of the new lease standard, and ASU 2018-11, Leases: Targeted Improvements, which was issued to provide relief to companies from restating comparative periods. Pursuant to this ASU, in the period of adoption the Company will not restate comparative periods presented in its condensed financial statements. On January 1, 2022, the Company adopted ASU 2016-12 using the modified retrospective transition method. Periods prior to January 1, 2022 have not been restated for the adoption of ASC 842 and continue to reflect the accounting treatment of leases in accordance with the prior lease accounting guidance, ASC 840, Leases. The Company adopted the new lease standard using a cumulative effect to accumulated deficit and there was no impact to accumulated deficit upon adoption. The Company elected the package of practical expedients, which among other things allowed the Company to carry forward its historical lease classification. As part of the adoption, the Company recorded operating lease liabilities of $6.4 million, operating lease ROU assets of $5.9 million, adjusted for deferred rent and lease incentive obligations of $0.5 million previously included in other non-current liabilities and accrued and other current liabilities, pertaining to its office and laboratory space operating leases. See Note 5 for details on the Company's leases.

Other Financial Information - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Other Financial Information [Abstract]
Depreciation and amortization	$ 0.4	$ 0.3	$ 1.0	$ 0.7

Unaudited Condensed Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2020		12,652,308
Beginning balance at Dec. 31, 2020	$ 41,839	$ 13	$ 223,115	$ (181,289)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock in public offering, net of issuance costs of $4,435 (in shares)		4,255,000
Issuance of stock in public offering, net of issuance costs of $4,435	64,709	$ 4	64,705
Exercise of stock options (in shares)		3,381
Exercise of stock options	44		44
Issuance of stock under Employee Stock Purchase Plan (in shares)		14,991
Issuance of stock under Employee Stock Purchase Plan	175		175
Stock-based compensation	912		912
Net loss	(6,209)			(6,209)
Ending balance (in shares) at Mar. 31, 2021		16,925,680
Ending balance at Mar. 31, 2021	101,470	$ 17	288,951	(187,498)
Beginning balance (in shares) at Dec. 31, 2020		12,652,308
Beginning balance at Dec. 31, 2020	41,839	$ 13	223,115	(181,289)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(19,798)
Ending balance (in shares) at Sep. 30, 2021		16,164,232
Ending balance at Sep. 30, 2021	90,803	$ 16	291,874	(201,087)
Beginning balance (in shares) at Mar. 31, 2021		16,925,680
Beginning balance at Mar. 31, 2021	101,470	$ 17	288,951	(187,498)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Retirement of common stock in exchange for common stock warrant (in shares)		(804,951)
Retirement of common stock in exchange for common stock warrant	(12,775)	$ (1)	(12,774)
Issuance of common stock warrant in exchange for retirement of common stock	12,775		12,775
Exercise of stock options (in shares)		6,055
Exercise of stock options	35		35
Stock-based compensation	1,285		1,285
Net loss	(6,410)			(6,410)
Ending balance (in shares) at Jun. 30, 2021		16,126,784
Ending balance at Jun. 30, 2021	96,380	$ 16	290,272	(193,908)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)		1,752
Exercise of stock options	1		1
Issuance of stock under Employee Stock Purchase Plan (in shares)		17,977
Issuance of stock under Employee Stock Purchase Plan	215		215
Stock-based compensation	1,354		1,354
Exercise of common stock warrants (in shares)		17,719
Exercise of common stock warrants	32		32
Net loss	(7,179)			(7,179)
Ending balance (in shares) at Sep. 30, 2021		16,164,232
Ending balance at Sep. 30, 2021	$ 90,803	$ 16	291,874	(201,087)
Beginning balance (in shares) at Dec. 31, 2021	16,164,994	16,164,994
Beginning balance at Dec. 31, 2021	$ 84,936	$ 16	293,060	(208,140)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock from vested restricted stock units and payment of employees' taxes (in shares)		30,523
Issuance of stock from vested restricted stock units and payment of employees' taxes	(115)		(115)
Issuance of stock under Employee Stock Purchase Plan (in shares)		35,681
Issuance of stock under Employee Stock Purchase Plan	231		231
Stock-based compensation	1,376		1,376
Net loss	(10,272)			(10,272)
Ending balance (in shares) at Mar. 31, 2022		16,231,198
Ending balance at Mar. 31, 2022	$ 76,156	$ 16	294,552	(218,412)
Beginning balance (in shares) at Dec. 31, 2021	16,164,994	16,164,994
Beginning balance at Dec. 31, 2021	$ 84,936	$ 16	293,060	(208,140)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(24,937)
Ending balance (in shares) at Jun. 30, 2022		16,258,807
Ending balance at Jun. 30, 2022	$ 62,824	$ 16	295,885	(233,077)
Beginning balance (in shares) at Dec. 31, 2021	16,164,994	16,164,994
Beginning balance at Dec. 31, 2021	$ 84,936	$ 16	293,060	(208,140)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of common stock warrants (in shares)	0
Net loss	$ (33,033)
Ending balance (in shares) at Sep. 30, 2022	16,305,475	16,305,475
Ending balance at Sep. 30, 2022	$ 56,186	$ 16	297,343	(241,173)
Beginning balance (in shares) at Mar. 31, 2022		16,231,198
Beginning balance at Mar. 31, 2022	76,156	$ 16	294,552	(218,412)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock from vested restricted stock units and payment of employees' taxes (in shares)		27,609
Issuance of stock from vested restricted stock units and payment of employees' taxes	(107)		(107)
Stock-based compensation	1,440		1,440
Net loss	(14,665)			(14,665)
Ending balance (in shares) at Jun. 30, 2022		16,258,807
Ending balance at Jun. 30, 2022	62,824	$ 16	295,885	(233,077)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of stock from vested restricted stock units and payment of employees' taxes (in shares)		5,336
Issuance of stock from vested restricted stock units and payment of employees' taxes	(2)		(2)
Exercise of stock options (in shares)		1,273
Exercise of stock options	0		0
Issuance of stock under Employee Stock Purchase Plan (in shares)		40,059
Issuance of stock under Employee Stock Purchase Plan	154		154
Stock-based compensation	$ 1,306		1,306
Exercise of common stock warrants (in shares)	0
Net loss	$ (8,096)			(8,096)
Ending balance (in shares) at Sep. 30, 2022	16,305,475	16,305,475
Ending balance at Sep. 30, 2022	$ 56,186	$ 16	$ 297,343	$ (241,173)

Stockholders' Equity

9 Months Ended

Sep. 30, 2022

Equity [Abstract]

Stockholders' Equity

Common Stock

Shelf Registration Statement

On November 10, 2020, the Company filed a registration statement on Form S-3 (the Shelf Registration Statement), covering the offering, from time to time, of up to $150.0 million of common stock, preferred stock, debt securities, warrants and units, which Shelf Registration Statement became effective on November 19, 2020.

On March 25, 2021, the Company completed a public offering of 4,255,000 shares of its common stock at a public offering price of $16.25 per share. Net proceeds from the offering were approximately $64.7 million, after deducting underwriting discounts, commissions and other offering expenses of $4.4 million. The shares were registered pursuant to the Company's Shelf Registration Statement discussed above.

At The Market Sales Agreement

On September 15, 2022, the Company entered into a sales agreement (the Sales Agreement) with Cowen and Company, LLC (the Sales Agent), pursuant to which the Company may offer and sell, from time to time, shares of Company common stock having an aggregate offering price of up to $50.0 million. The Company is not obligated to sell any shares of Company common stock in the offering. As of September 30, 2022, the Company has not sold any shares of its common stock pursuant to the Sales Agreement.

Exchange Agreement

On June 22, 2021, the Company entered into an exchange agreement (the Exchange Agreement) with an Investor and its affiliates (the Exchanging Stockholders), pursuant to which the Company exchanged an aggregate of 804,951 shares of the Company's common stock owned by the Exchanging Stockholders for pre-funded warrants (the Exchange Warrants) to purchase an aggregate of 804,951 shares of common stock (subject to adjustment in the event of any stock dividends and splits, reverse stock split, recapitalization, reorganization or similar transaction, as described in the Exchange Warrants), with an exercise price of $0.001 per share. The Exchange Warrants do not expire and are exercisable at any time except that the Exchange Warrants cannot be exercised by the Exchanging Stockholders if, after giving effect thereto, the Exchanging Stockholders would beneficially own more than 4.99% of the Company's common stock, which percentage may change at the Exchanging Stockholder's election to any other

percentage upon 61 days' notice to the Company. The Company recorded the retirement of common stock exchanged as a reduction of common shares outstanding and additional paid-in-capital at the fair value of the Exchange Warrants on the issuance date. The Exchange Warrants are classified as equity and the fair value of the Exchange Warrants was recorded as an increase to additional paid-in-capital and is not subject to remeasurement. The Company determined that the fair value of the Exchange Warrants is substantially similar to the fair value of the retired shares on the issuance date due to the negligible exercise price for the Exchange Warrants. As of September 30, 2022, none of the Exchange Warrants have been exercised.

Outstanding Warrants

The following equity classified warrants to purchase common stock were outstanding as of September 30, 2022:


	Shares	Exercise Price		Issuance date	Expiration date
Common stock warrants	237,169	$	1.84	January 19, 2016	January 19, 2026
Common stock warrants	67,086	$	1.84	March 31, 2016	March 31, 2026
Common stock warrants	131	$	1.84	April 1, 2016	April 1, 2026
Common stock warrants	83,778	$	14.32	September 7, 2017	September 7, 2024
Common stock warrants	20,944	$	14.32	December 7, 2018	December 7, 2025
Common stock warrants (Exchange Warrants)	804,951	$	0.001	June 22, 2021	None
	1,214,059

During the three and nine months ended September 30, 2022, no warrants to purchase common stock were exercised.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

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-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496189-112644

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 16
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496180-112644

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (i)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 40
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126731327&loc=SL126733271-114008

+ Details

Fair Value Measurements

9 Months Ended

Sep. 30, 2022

Fair Value Disclosures [Abstract]

Fair Value Measurements

The following table sets forth the Company's financial instruments that were measured at fair value on a recurring basis within the fair value hierarchy (in thousands):


	September 30, 2022
	Total		Level 1		Level 2		Level 3
Assets:
Money market funds, included in cash and cash equivalents	$	35,328	$	35,328	$	—	$	—


	December 31, 2021
	Total		Level 1		Level 2		Level 3
Assets:
Money market funds, included in cash and cash equivalents	$	95,761	$	95,761	$	—	$	—

The fair value of the Company's money market funds is based on quoted market prices.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Borrowings - Narrative (Details)		1 Months Ended		3 Months Ended		9 Months Ended
Borrowings - Narrative (Details)	Dec. 07, 2018 USD ($)	Nov. 30, 2021 USD ($) installment	Sep. 30, 2017 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)
Loan payable \| Capital Royalty Partners II LP
Debt Instrument [Line Items]
Loan repayment			$ 17,800,000
2017 Term loan \| Loan payable \| Innovatus Life Sciences Lending Fund
Debt Instrument [Line Items]
Term loan borrowings	$ 5,000,000		$ 20,000,000			$ 0
Term loan, interest rate		8.00%
Term loan, paid in-kind, interest rate		2.00%
Term loan, effective interest rate		8.50%
Number of monthly installments \| installment		24
Term loan, fee incurred upon payment of final installment				$ 1,000,000		$ 1,000,000
Term loan, prepayment premium percentage		3.00%
Term loan, annual reduction in prepayment penalty percentage		1.00%
Term loan, covenant, revenue performance period						12 months
Term loan, covenant, number of days to cure covenant if performance measure is not met						60 days
Term loan covenant, minimum unrestricted cash balance		$ 2,000,000.0
Term loan covenant, increase to interest rate				4.00%		4.00%
2017 Term loan \| Paid in-kind note \| Innovatus Life Sciences Lending Fund
Debt Instrument [Line Items]
Term loan, paid in-kind loans issued				$ 100,000	$ 100,000	$ 400,000	$ 400,000

Stock Option Plan

9 Months Ended

Sep. 30, 2022

Share-Based Payment Arrangement [Abstract]

Stock Option Plan

2019 Incentive Award Plan

In September 2019, the Company's Board of Directors adopted, and the Company's stockholders approved, the 2019 Plan. Under the 2019 Plan, which expires in September 2029, the Company may grant stock options, stock appreciation rights, restricted stock, restricted stock units and other awards to individuals who are then employees, officers, non-employee directors or consultants of the Company or its subsidiaries. The options generally expire ten years after the date of grant and are exercisable to the extent vested. Vesting is established by the Board of Directors and is generally four years from the date of grant or, for grants to new hires, date of hire. As of September 30, 2022, 1,528,877 shares of common stock remained available for future awards.

2019 Employee Stock Purchase Plan

In September 2019, the Board of Directors adopted, and the Company's stockholders approved, the ESPP. The ESPP became effective on the day the ESPP was adopted by the Company's Board of Directors. The ESPP permits participants to purchase common stock through payroll deductions of up to 20% of their eligible compensation. As of September 30, 2022, 413,425 shares of common stock remained available for issuance under the ESPP.

Stock Options

Stock option activity under the Company's 2019 Plan is set forth below:


	Number of Options	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value (in thousands)
Outstanding, December 31, 2021	2,014,330	$	12.10	7.87	$	5,428
Granted	63,000	$	5.25
Exercised	(1,273)	$	0.33
Forfeited	(114,182)	$	13.74
Expired	(141,320)	$	13.79
Outstanding, September 30, 2022	1,820,555	$	11.63	7.19	$	1,150
Vested and expected to vest, September 30, 2022	1,820,555	$	11.63	7.19	$	1,150
Options exercisable, September 30, 2022	1,321,485	$	10.59	6.93	$	1,126

The intrinsic value is calculated as the difference between the fair value of the Company's common stock and the exercise price of the stock options. As of September 30, 2022, total unrecognized compensation cost related to option awards was $3.5 million, which is expected to be recognized over a remaining weighted-average vesting period of 1.36 years.

Restricted Stock Units

Restricted stock unit activity under the Company's 2019 Plan is set forth below:


	Number of Shares	Weighted- Average Grant Date Fair Value		Aggregate Intrinsic Value (in thousands)
Outstanding, December 31, 2021	415,325	$	16.54	$	4,830
Awards granted	604,100	$	8.61
Awards released	(99,624)	$	16.62
Awards canceled	(114,305)	$	11.72
Outstanding, September 30, 2022	805,496	$	11.27	$	2,183

As of September 30, 2022, total unrecognized compensation cost related to restricted stock units was $7.7 million, which is expected to be recognized over a remaining weighted-average vesting period of 3.1 years.

Stock-Based Compensation Expense

Stock Options

The fair value of employee stock options was estimated using the following assumptions to determine the fair value of stock options granted:


	Three Months Ended September 30,		Nine Months Ended September 30,
	2022	2021	2022	2021
Expected volatility	—%	86%	54%	83%-86%
Risk-free interest rate	—%	0.9%	3.4%	0.8%-1.1%
Dividend yield	—	—	—	—
Expected term (in years)	0	5.77	5.5	5.50-6.08

There were no stock options granted in the three months ended September 30, 2022.

Employee Stock Purchase Plan

The following assumptions were used to calculate the stock-based compensation for each stock purchase right granted under the ESPP:


	Three Months Ended September 30,		Nine Months Ended September 30,
	2022	2021	2022	2021
Expected volatility	45%	45%	45%-57%	45%-60%
Risk-free interest rate	0.6%	0.1%	0.6%-3.3%	0.1%
Dividend yield	—	—	—	—
Expected term (in years)	0.50	0.50	0.50	0.50

Stock-based compensation expense for the ESPP was less than $0.1 million for the three and nine months ended September 30, 2022 and 2021. As of September 30, 2022, total unrecognized compensation cost related to stock purchase rights granted under the ESPP was less than $0.1 million, which is expected to be recognized over a remaining weighted-average vesting period of 0.41 years.


	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Costs of revenue	$	56	$	64	$	159	$	136
Selling, general and administrative	1,085		1,115		3,406		2,955
Research and development	165		175		557		460
Total	$	1,306	$	1,354	$	4,122	$	3,551

Leases - Narrative (Details) - USD ($)		3 Months Ended	9 Months Ended
Leases - Narrative (Details) - USD ($)	Aug. 23, 2021	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2022
Loss Contingencies [Line Items]
Operating lease, rent expense		$ 200,000	$ 500,000
Office and Laboratory
Loss Contingencies [Line Items]
Operating lease, renewal term				5 years
Office
Loss Contingencies [Line Items]
Operating lease monthly base rent	$ 66,021
Operating lease annual increase in base rent payment percent	3.00%
Minimum
Loss Contingencies [Line Items]
Finance lease, term of contract				3 years
Maximum
Loss Contingencies [Line Items]
Finance lease, term of contract				5 years

Borrowings - Future Minimum Payments (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Debt Disclosure [Abstract]
2022 (remaining)	$ 420
2023	1,686
2024	2,980
2025	16,152
2026	14,786
Total	36,024
Unamortized debt discount and issuance costs	(170)
Interest	(7,846)
Total borrowings, net of discounts and debt issuance costs	$ 28,008

Organization	9 Months Ended
Organization	Sep. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	Organization Description of Business Exagen Inc. (the Company) is dedicated to transforming the care continuum for patients suffering from debilitating and chronic autoimmune diseases by enabling timely differential diagnosis and optimizing therapeutic intervention. Liquidity The Company has incurred recurring losses and negative cash flows from operating activities since inception. The Company anticipates that it will continue to incur net losses into the foreseeable future. As of September 30, 2022, the Company had cash and cash equivalents of $68.7 million and had an accumulated deficit of $241.2 million. Since inception, the Company has financed its operations primarily through a combination of equity financings of common stock and private placements of preferred securities, debt financing arrangements, and revenue from sales of the Company's products. Based on the Company's current business plan, management believes that its existing capital resources will be sufficient to fund the Company's obligations for at least twelve months following the issuance of these condensed financial statements. To execute its business plans, the Company may need additional funding to support its continuing operations and pursue its growth strategy. Until such time as the Company can achieve significant cash flows from operations, if ever, it expects to finance its operations through the sale of its stock, debt financings or other strategic transactions. Although the Company has been successful in raising capital in the past, there is no assurance that it will be successful in obtaining such additional financing on terms acceptable to the Company, if at all. The terms of any financing may adversely affect the holdings or the rights of the Company's stockholders. If the Company is unable to obtain funding, the Company could be forced to delay, reduce or eliminate some or all of its programs, product portfolio expansion plans or commercialization efforts, which could have a material adverse effect on the Company's business, operating results and financial condition and the Company's ability to achieve its intended business objectives.

Leases (Tables)

9 Months Ended

Sep. 30, 2022

Leases [Abstract]

Summary of Lease Costs

Operating and finance leases consist of the following (in thousands):

Lease Balance

Classification

September 30, 2022

Lease Assets

Operating

Operating lease right-of-use assets

5,114

Finance

Property and equipment, net

1,696

Lease Liabilities

Current

Operating

Operating lease liabilities

1,009

Finance

Accrued and other current liabilities

730

Non-current

Operating

Non-current operating lease liabilities

4,766

Finance

Other non-current liabilities

974

Costs associated with the Company's leases were included in the statements of operations as follows (in thousands):


Lease Cost	Three months ended September 30, 2022		Nine months ended September 30, 2022
Operating leases
Operating lease cost(1)	$	384	$	1,156
Finance lease cost
Amortization of lease assets	174		487
Interest on finance lease liabilities	20		60
Total lease cost	$	578	$	1,703

(1) Includes variable lease cost of $41,000 and $124,000 for the three and nine months ended September 30, 2022, respectively.

Supplemental cash flow information on leases is as follows (in thousands):


Cash paid for amounts included in the measurement of lease liabilities	Nine months ended September 30, 2022
Operating cash out flows from operating leases	$	907
Operating cash out flows from interest paid on finance leases	$	60
Financing cash out flows from finance leases	$	477

Information regarding the weighted-average lease term and weighted average discount rate are as follows:


	September 30, 2022
Weighted-average remaining lease term (years)
Operating leases	4.6
Finance leases	2.29
Weighted-average discount rate
Operating leases	8.0	%
Finance leases	5.3	%

Summary of Lessee, Operating Lease, Liability, Maturity

Future payments under operating and finance leases as of September 30, 2022 are as follows (in thousands):


	Operating Leases		Finance Leases
2022 (remaining)	$	356	$	227
2023	1,446		827
2024	1,489		573
2025	1,533		247
2026	1,584		127
Thereafter	539		28
Total minimum lease payments	6,947		2,029
Less: imputed interest	(1,172)		(325)
Total lease liabilities	5,775		1,704
Less: current portion	(1,009)		(730)
Lease obligations, net of current portion	$	4,766	$	974

Summary of Finance Lease, Liability, Maturity

Future payments under operating and finance leases as of September 30, 2022 are as follows (in thousands):


	Operating Leases		Finance Leases
2022 (remaining)	$	356	$	227
2023	1,446		827
2024	1,489		573
2025	1,533		247
2026	1,584		127
Thereafter	539		28
Total minimum lease payments	6,947		2,029
Less: imputed interest	(1,172)		(325)
Total lease liabilities	5,775		1,704
Less: current portion	(1,009)		(730)
Lease obligations, net of current portion	$	4,766	$	974

Schedule of Future Minimum Rental Payments for Operating Leases

Minimum annual lease payments under non-cancelable operating lease arrangements as of December 31, 2021 are as follows (in thousands):


Years Ending December 31,	Operating Leases
2022	$	1,337
2023	1,445
2024	1,489
2025	1,533
2026	1,584
Thereafter	539
Total minimum lease payments	$	7,927

Stock Option Plan - Restricted Stock Units (Details) - Restricted stock units - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding, December 31, 2021 (in shares)	415,325
Awards granted (in shares)	604,100
Awards released (in shares)	(99,624)
Awards canceled (in shares)	(114,305)
Outstanding, March 31, 2022 (in shares)	805,496
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Outstanding, December 31, 2021 (in dollars per share)	$ 16.54
Awards granted, Weighted-Average Grant Date Fair Value (in dollars per share)	8.61
Awards released, Weighted-Average Grant Date Fair Value (in dollars per share)	16.62
Awards canceled, Weighted-Average Grant Date Fair Value (in dollars per share)	11.72
Outstanding, March 31, 2022 (in dollars per share)	$ 11.27
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value [Abstract]
Outstanding, Aggregate Intrinsic Value	$ 2,183	$ 4,830

Leases - Lease Balances (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Leases [Abstract]
Operating lease right-of-use assets	$ 5,114	$ 0
Finance lease, right-of-use asset, after accumulated amortization	$ 1,696
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Property and equipment, net
Operating lease liabilities	$ 1,009	0
Finance lease obligations, current portion	730	587
Non-current operating lease liabilities	4,766	$ 0
Lease obligations, net of current portion	$ 974
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Accrued and other current liabilities
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Other non-current liabilities

Restatement of Previously Issued Financial Statements - Impact Of Restatement (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended	9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2021	Jun. 30, 2022	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue	$ 14,726	$ 7,606	$ 12,251	$ 18,000	$ 32,726	$ 35,610
Accounts receivable, net	10,639	8,715		8,715	10,639		$ 9,654
Accrued and other current liabilities	$ 6,654	5,970		5,970	$ 6,654		$ 6,826
Adjustments
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Revenue		(1,356)		(1,356)
Accounts receivable, net		(875)		(875)
Accrued and other current liabilities		$ 481		$ 481

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8906-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 40
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e9031-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e9038-108599

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8933-108599

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130543-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8736-108599

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e9054-108599

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI https://asc.fasb.org/extlink&oid=126920106&loc=SL49130545-203045

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 924
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 11.L)
-URI https://asc.fasb.org/extlink&oid=6472922&loc=d3e499488-122856

+ Details

Summary of Significant Accounting Policies - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended	9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2021	Jun. 30, 2022	Sep. 30, 2022	Sep. 30, 2021
Disaggregation of Revenue [Line Items]
Revenue	$ 14,726	$ 7,606	$ 12,251	$ 18,000	$ 32,726	$ 35,610
Healthcare insurers
Disaggregation of Revenue [Line Items]
Revenue	3,216		6,910		14,259	20,318
Government
Disaggregation of Revenue [Line Items]
Revenue	9,228		2,330		12,242	6,733
Client
Disaggregation of Revenue [Line Items]
Revenue	2,046		2,346		5,496	6,738
Other
Disaggregation of Revenue [Line Items]
Revenue	236		265		729	821
Janssen (SIMPONI)
Disaggregation of Revenue [Line Items]
Revenue	$ 0		$ 400		$ 0	$ 1,000

- Definition

+ References

+ Details

Leases - Future Payments Under Operating And Finance Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Lessee, Operating Lease, Liability, Payment, Due [Abstract]
2022 (remaining)	$ 356
2023	1,446
2024	1,489
2025	1,533
2026	1,584
Thereafter	539
Total minimum lease payments	6,947
Less: imputed interest	(1,172)
Total lease liabilities	5,775
Less: current portion	(1,009)	$ 0
Lease obligations, net of current portion	4,766	0
Finance Lease, Liability, Payment, Due [Abstract]
2022 (remaining)	227
2023	827
2024	573
2025	247
2026	127
Thereafter	28
Total minimum lease payments	2,029
Less: imputed interest	(325)
Total lease liabilities	1,704
Less: current portion	(730)	$ (587)
Lease obligations, net of current portion	$ 974

Stockholders' Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	Sep. 15, 2022	Jun. 22, 2021	Mar. 25, 2021	Nov. 10, 2020	Sep. 30, 2022	Mar. 31, 2021
Class of Stock [Line Items]
Estimated offering expenses for aggregate expenses						$ 4,435
Number of warrants exercised (in shares)					0
Cowen Equity Distribution Agreement
Class of Stock [Line Items]
Proceeds from sale of stock	$ 50,000
Exchanging Stockholders
Class of Stock [Line Items]
Number of shares exchanged for warrants (in shares)		804,951
Class of warrant or right, exercise price of warrants or rights (in dollars per share)		$ 0.001
Sale of stock, percentage of ownership after transaction		4.99%
Beneficial ownership election period (in days)		61 days
Common Stock
Class of Stock [Line Items]
Sale of stock, number shares issued (in shares)			4,255,000	150,000,000
Shares issued in public offering, price per share (in dollars per share)			$ 16.25
Proceeds from sale of stock			$ 64,700
Estimated offering expenses for aggregate expenses			$ 4,400

Leases - Supplemental Cash Flow Information On Leases And Weighted-Average Lease Term (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Cash paid for amounts included in the measurement of lease liabilities
Operating cash out flows from operating leases	$ 907
Operating cash out flows from interest paid on finance leases	60
Financing cash out flows from finance leases	$ 477	$ 343
Weighted-average remaining lease term (years)
Operating leases	4 years 7 months 6 days
Finance leases	2 years 3 months 14 days
Weighted-average discount rate
Operating leases	8.00%
Finance leases	5.30%

Leases

9 Months Ended

Sep. 30, 2022

Leases [Abstract]

Leases

The Company adopted ASC 842, Leases, as of January 1, 2022. Prior period amounts have not been adjusted and continue to be reported in accordance with the Company's historic accounting under ASC 840, Leases.

Operating Leases

The Company leases office and laboratory spaces in Vista, California, under leases that expire in April 2027, with an option to extend portions of the leases for additional 5-year periods. The Company has not included the optional renewal periods in the measurement of the lease liabilities because it is not reasonably certain that the Company will exercise these renewal options. The Company's lease payments under each of these leases are subject to escalation clauses.

Effective on August 23, 2021, the Company entered into a sub-lease agreement for an additional office space in Carlsbad, California. The sub-lease commenced in October 2021 and expires in April 2027. The sub-lease agreement provides for monthly base rent of $66,021 which began on October 1, 2021, and such amount shall increase by approximately 3% annually beginning October 1, 2022. The Company is entitled to base rent abatement for a specified period of time which began on November 1, 2021.

The Company determines if a contract contains a lease at inception or modification of a contract. The Company discounts their lease obligations using its incremental borrowing rate at the commencement date. The incremental borrowing rate is the rate of interest the Company would have to pay to borrow on a collateralized basis over a

similar term and amount equal to the lease payments in a similar economic environment. The Company primarily considers industry data, its credit rating and the lease term to determine its incremental borrowing rate.

Finance Leases

The Company has entered into various finance lease agreements to obtain laboratory equipment. The terms of the Company's finance leases generally range from three to five years and are typically secured by the underlying equipment. The portion of the future payments designated as principal repayments were classified as finance lease liabilities on the Company's balance sheet.

Operating and Finance Leases Balances and Costs

Operating and finance leases consist of the following (in thousands):

Lease Balance

Classification

September 30, 2022

Lease Assets

Operating

Operating lease right-of-use assets

5,114

Finance

Property and equipment, net

1,696

Lease Liabilities

Current

Operating

Operating lease liabilities

1,009

Finance

Accrued and other current liabilities

730

Non-current

Operating

Non-current operating lease liabilities

4,766

Finance

Other non-current liabilities

974

Costs associated with the Company's leases were included in the statements of operations as follows (in thousands):


Lease Cost	Three months ended September 30, 2022		Nine months ended September 30, 2022
Operating leases
Operating lease cost(1)	$	384	$	1,156
Finance lease cost
Amortization of lease assets	174		487
Interest on finance lease liabilities	20		60
Total lease cost	$	578	$	1,703

(1) Includes variable lease cost of $41,000 and $124,000 for the three and nine months ended September 30, 2022, respectively.

Supplemental cash flow information on leases is as follows (in thousands):


Cash paid for amounts included in the measurement of lease liabilities	Nine months ended September 30, 2022
Operating cash out flows from operating leases	$	907
Operating cash out flows from interest paid on finance leases	$	60
Financing cash out flows from finance leases	$	477

Information regarding the weighted-average lease term and weighted average discount rate are as follows:


	September 30, 2022
Weighted-average remaining lease term (years)
Operating leases	4.6
Finance leases	2.29
Weighted-average discount rate
Operating leases	8.0	%
Finance leases	5.3	%

Future payments under operating and finance leases as of September 30, 2022 are as follows (in thousands):


	Operating Leases		Finance Leases
2022 (remaining)	$	356	$	227
2023	1,446		827
2024	1,489		573
2025	1,533		247
2026	1,584		127
Thereafter	539		28
Total minimum lease payments	6,947		2,029
Less: imputed interest	(1,172)		(325)
Total lease liabilities	5,775		1,704
Less: current portion	(1,009)		(730)
Lease obligations, net of current portion	$	4,766	$	974

Disclosures Under ASC 840

Minimum annual lease payments under non-cancelable operating lease arrangements as of December 31, 2021 are as follows (in thousands):


Years Ending December 31,	Operating Leases
2022	$	1,337
2023	1,445
2024	1,489
2025	1,533
2026	1,584
Thereafter	539
Total minimum lease payments	$	7,927

For the three and nine months ended September 30, 2021, rent expense was $0.2 million and $0.5 million, respectively.

Leases

Operating Leases

Finance Leases

Operating and Finance Leases Balances and Costs

Operating and finance leases consist of the following (in thousands):

Lease Balance

Classification

September 30, 2022

Lease Assets

Operating

Operating lease right-of-use assets

5,114

Finance

Property and equipment, net

1,696

Lease Liabilities

Current

Operating

Operating lease liabilities

1,009

Finance

Accrued and other current liabilities

730

Non-current

Operating

Non-current operating lease liabilities

4,766

Finance

Other non-current liabilities

974

Costs associated with the Company's leases were included in the statements of operations as follows (in thousands):


Lease Cost	Three months ended September 30, 2022		Nine months ended September 30, 2022
Operating leases
Operating lease cost(1)	$	384	$	1,156
Finance lease cost
Amortization of lease assets	174		487
Interest on finance lease liabilities	20		60
Total lease cost	$	578	$	1,703

(1) Includes variable lease cost of $41,000 and $124,000 for the three and nine months ended September 30, 2022, respectively.

Supplemental cash flow information on leases is as follows (in thousands):


Cash paid for amounts included in the measurement of lease liabilities	Nine months ended September 30, 2022
Operating cash out flows from operating leases	$	907
Operating cash out flows from interest paid on finance leases	$	60
Financing cash out flows from finance leases	$	477

Information regarding the weighted-average lease term and weighted average discount rate are as follows:


	September 30, 2022
Weighted-average remaining lease term (years)
Operating leases	4.6
Finance leases	2.29
Weighted-average discount rate
Operating leases	8.0	%
Finance leases	5.3	%

Future payments under operating and finance leases as of September 30, 2022 are as follows (in thousands):


	Operating Leases		Finance Leases
2022 (remaining)	$	356	$	227
2023	1,446		827
2024	1,489		573
2025	1,533		247
2026	1,584		127
Thereafter	539		28
Total minimum lease payments	6,947		2,029
Less: imputed interest	(1,172)		(325)
Total lease liabilities	5,775		1,704
Less: current portion	(1,009)		(730)
Lease obligations, net of current portion	$	4,766	$	974

Disclosures Under ASC 840

Minimum annual lease payments under non-cancelable operating lease arrangements as of December 31, 2021 are as follows (in thousands):


Years Ending December 31,	Operating Leases
2022	$	1,337
2023	1,445
2024	1,489
2025	1,533
2026	1,584
Thereafter	539
Total minimum lease payments	$	7,927

For the three and nine months ended September 30, 2021, rent expense was $0.2 million and $0.5 million, respectively.

Stock Option Plan - Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 1,306	$ 1,354	$ 4,122	$ 3,551
Costs of revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	56	64	159	136
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	1,085	1,115	3,406	2,955
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 165	$ 175	$ 557	$ 460

Subsequent Events (Details) - Subsequent Event - Restricted stock units	1 Months Ended
	Oct. 31, 2022 shares
Subsequent Event [Line Items]
Stock issued in connection with appointment (in shares)	350,000
Stock options, vesting period	4 years

Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands	3 Months Ended			6 Months Ended	9 Months Ended
	Sep. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Jun. 30, 2022 USD ($)	Sep. 30, 2022 USD ($) installment segment	Sep. 30, 2021 USD ($)	Jan. 01, 2022 USD ($)	Dec. 31, 2021 USD ($)
New Accounting Pronouncement, Early Adoption [Line Items]
Restricted cash	$ 200		$ 100		$ 200	$ 100		$ 100
(Decrease) increase in variable consideration	3,700		100		(2,500)	200
Revenue recognized in previous periods	1,900
Revenue	14,726	$ 7,606	12,251	$ 18,000	32,726	35,610
Advertising expense	1,300		600		$ 2,200	1,300
Number of operating segments \| segment					1
Operating lease liabilities	5,775				$ 5,775
Operating lease right-of-use assets	5,114				$ 5,114			0
Cumulative Effect, Period of Adoption, Adjustment \| Accounting Standards Update 2016-02
New Accounting Pronouncement, Early Adoption [Line Items]
Operating lease liabilities							$ 6,400
Operating lease right-of-use assets							5,900
Deferred rent credit							$ 500
Janssen Promotion Agreement
New Accounting Pronouncement, Early Adoption [Line Items]
Termination of agreement								$ 600
Restricted stock units
New Accounting Pronouncement, Early Adoption [Line Items]
Number of annual vesting installments \| installment					4
Janssen (SIMPONI)
New Accounting Pronouncement, Early Adoption [Line Items]
Revenue	0		400		$ 0	1,000
Shipping and Handling
New Accounting Pronouncement, Early Adoption [Line Items]
Cost of revenue	$ 700		$ 600		$ 2,100	$ 1,600
Revenue Benchmark \| Product Concentration Risk \| AVISE CTD Test
New Accounting Pronouncement, Early Adoption [Line Items]
Percent of total revenue	87.00%		81.00%		84.00%	81.00%
Revenue Benchmark \| Supplier Concentration Risk \| Two Major Suppliers
New Accounting Pronouncement, Early Adoption [Line Items]
Percent of total revenue	97.00%		95.00%		96.00%	96.00%

Other Financial Information - Accrued and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Other Financial Information [Abstract]
Accrued payroll and related expenses	$ 3,353		$ 4,048
Accrued interest	136		139
Accrued purchases of goods and services	1,227		510
Accrued royalties	69		180
Accrued clinical study activity	165		254
Finance lease obligations, current portion	730		587
Refund liability	445		0
Other accrued liabilities	529		1,108
Accrued and other current liabilities	$ 6,654	$ 5,970	$ 6,826

Commitment and Contingencies	9 Months Ended
Commitment and Contingencies	Sep. 30, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Acquisition-related liabilities In connection with the acquisition of the medical diagnostics division of Royalty Pharma Collection Trust (Royalty Pharma) (formerly known as Cypress Bioscience, Inc.) in 2010, the Company was required to pay certain amounts in the event that certain revenue milestones were achieved and upon the first commercial sale of a product associated with this acquisition, for which the obligations no longer exist. In addition, the Company has ongoing royalty payment obligations with Royalty Pharma of 2.5% on net sales of products which incorporate certain acquired technologies. Future royalties payable under these arrangements are limited to the lesser of (i) an aggregate of $1.2 million (including an upfront payment of $0.1 million) and (ii) the total royalties earned through January 1, 2024. Licensing Agreements The Company has licensed technology for use in its diagnostic tests. In addition to the milestone payments required by these agreements as described above, individual license agreements generally provide for ongoing royalty payments ranging from 1.5% to 7.0% on net sales of products which incorporate licensed technology, as defined in such agreements. Royalties are accrued when earned and recorded in costs of revenue in the accompanying condensed statements of operations. In May 2021, the Company entered into an exclusive license agreement with Allegheny Health Network Research Institute (AHN), to obtain an exclusive license to AHN's patent rights in certain inventions, pursuant to which the Company paid AHN an initial license fee of $0.4 million. In addition, under the terms of the exclusive license agreement, the Company is required to pay the greater of royalties in the low single digits on net sales of diagnostic tests using the assigned patents or a flat annual minimum royalty amount, pending approvals and commercialization. In November 2021, the Company entered into an exclusive license agreement with Queen Mary University of London (QMUL), to obtain an exclusive license to QMUL's patent rights in certain inventions, pursuant to which the Company paid QMUL an initial license fee of $0.4 million. The Company is obligated to make a one-time payment of $0.1 million relating to the first commercial sale of the licensed products. In addition, after the first 18 months of commercial sales under the terms of the exclusive license agreement, the Company is required to pay royalties in the high single-digits on net sales of testing products using the assigned patents, pending approvals and commercialization. Supply Agreement In December 2021, the Company entered into an amended supply agreement with one supplier for reagents which includes minimum annual purchase commitments of $6.0 million and $6.9 million for the years ending December 31, 2022 and 2023, respectively, with a 15% annual increase thereafter for unconditional minimum purchase commitments through the year ending December 31, 2025. Collaboration Obligations In May 2021, the Company entered into a master research collaboration agreement with AHN, pursuant to which the Company is required to pay AHN a collaboration fee of $0.4 million for each year during the initial term of the agreement. Collaboration expenses under the master research collaboration agreement were $0.1 million for each of the three months ended September 30, 2022 and 2021. Collaboration expenses under the master research collaboration agreement were $0.3 million and $0.2 million, for the nine months ended September 30, 2022 and 2021, respectively. Collaboration expenses under the AHN collaboration are included in research and development expenses. Contingencies In the normal course of business, the Company enters into contracts and agreements that contain a variety of representations and warranties and provide for general indemnifications; including for subpoenas and other civil investigative demands, from governmental agencies, Medicare or Medicaid payors and managed care organizations reviewing billing practices or requesting comment on allegations of billing irregularities that are brought to their attention through billing audits or third parties. The Company's exposure under these agreements is unknown because it involves claims that may be made against the Company in the future, but have not yet been made or that the Company believes to be immaterial. The Company accrues a liability for such matters when it is probable that future expenditures will be made and such expenditures can be reasonably estimated. Litigation From time to time, the Company may be subject to various legal proceedings that arise in the ordinary course of business activities. The Company does not believe the outcome of any such matters will have a material effect on its financial position or results of operations.

Stock Option Plan - Stock Option Activity (Details) - Stock options - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding, December 31, 2021 (in shares)		2,014,330
Granted (in shares)	0	63,000
Exercised (in shares)		(1,273)
Forfeited (in shares)		(114,182)
Expired (in shares)		(141,320)
Outstanding, March 31, 2022 (in shares)	1,820,555	1,820,555	2,014,330
Vested and expected to vest, March 31, 2022 (in shares)	1,820,555	1,820,555
Options exercisable, March 31, 2022 (in shares)	1,321,485	1,321,485
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Outstanding, December 31, 2021, Weighted Average Exercise Price (in dollars per share)		$ 12.10
Granted, Weighted Average Exercise Price (in dollars per share)		5.25
Exercised, Weighted Average Exercise Price (in dollars per share)		0.33
Forfeited, Weighted Average Exercise Price (in dollars per share)		13.74
Expired, Weighted Average Exercise Price (in dollars per share)		13.79
Outstanding, March 31, 2022, Weighted Average Exercise Price (in dollars per share)	$ 11.63	11.63	$ 12.10
Vested and expected to vest, March 31, 2022 (in shares), Weighted Average Exercise Price (in dollars per share)	11.63	11.63
Options exercised, March 31, 2022 (in shares), Weighted Average Exercise Price (in dollars per share)	$ 10.59	$ 10.59
Stock Options, Additional Disclosures [Abstract]
Outstanding, Weighted Average Remaining Contractual Term		7 years 2 months 8 days	7 years 10 months 13 days
Vested and expected to vest, Weighted Average Remaining Contractual Term		7 years 2 months 8 days
Options exercisable, Weighted Average Remaining Contractual Term		6 years 11 months 4 days
Outstanding, Aggregate Intrinsic Value	$ 1,150	$ 1,150	$ 5,428
Vested and expected to vest, Aggregate Intrinsic Value	1,150	1,150
Options exercisable, Aggregate Intrinsic Value	$ 1,126	$ 1,126

Stockholders' Equity - Schedule of Outstanding Warrants (Details)	3 Months Ended	9 Months Ended
	Sep. 30, 2022 $ / shares shares	Sep. 30, 2022 $ / shares shares
Class of Stock [Line Items]
Warrants issued to purchase redeemable convertible preferred stock (in shares)	1,214,059	1,214,059
Exercise of common stock warrants (in shares)	0	0
Warrant expiration January 19, 2026
Class of Stock [Line Items]
Warrants issued to purchase redeemable convertible preferred stock (in shares)	237,169	237,169
Class of warrant or right, exercise price of warrants or rights (in dollars per share) \| $ / shares	$ 1.84	$ 1.84
Warrant expiration March 31, 2026
Class of Stock [Line Items]
Warrants issued to purchase redeemable convertible preferred stock (in shares)	67,086	67,086
Class of warrant or right, exercise price of warrants or rights (in dollars per share) \| $ / shares	$ 1.84	$ 1.84
Warrant expiration April 1, 2026
Class of Stock [Line Items]
Warrants issued to purchase redeemable convertible preferred stock (in shares)	131	131
Class of warrant or right, exercise price of warrants or rights (in dollars per share) \| $ / shares	$ 1.84	$ 1.84
Warrant expiration September 7, 2024
Class of Stock [Line Items]
Warrants issued to purchase redeemable convertible preferred stock (in shares)	83,778	83,778
Class of warrant or right, exercise price of warrants or rights (in dollars per share) \| $ / shares	$ 14.32	$ 14.32
Warrant expiration December 7, 2025
Class of Stock [Line Items]
Warrants issued to purchase redeemable convertible preferred stock (in shares)	20,944	20,944
Class of warrant or right, exercise price of warrants or rights (in dollars per share) \| $ / shares	$ 14.32	$ 14.32
No expiration
Class of Stock [Line Items]
Warrants issued to purchase redeemable convertible preferred stock (in shares)	804,951	804,951
Class of warrant or right, exercise price of warrants or rights (in dollars per share) \| $ / shares	$ 0.001	$ 0.001

Unaudited Condensed Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Cash flows from operating activities:
Net loss	$ (33,033)	$ (19,798)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,037	656
Amortization of debt discount and debt issuance costs	119	226
Non-cash interest expense	411	403
Non-cash lease expense	738	0
Stock-based compensation	4,122	3,551
Other	33	0
Changes in assets and liabilities:
Accounts receivable, net	(985)	(300)
Prepaid expenses and other current assets	921	1,754
Other assets	(100)	(167)
Operating lease liabilities	(613)	0
Accounts payable	1,061	(1,085)
Accrued and other current liabilities	(121)	538
Net cash used in operating activities	(26,410)	(14,222)
Cash flows from investing activities:
Purchases of property and equipment	(3,912)	(1,306)
Purchase of other assets	0	(50)
Net cash used in investing activities	(3,912)	(1,356)
Cash flows from financing activities:
Proceeds from exercise of stock options	0	80
Payments of taxes withheld on vested restricted stock units	(224)	0
Proceeds from common stock issued under Employee Stock Purchase Plan	385	390
Proceeds from exercise of common stock warrants	0	32
Principal payments on finance lease obligations	(477)	(343)
Proceeds from the issuance of common stock in public offering	0	69,144
Payment of issuance costs related to public offering	0	(4,407)
Net cash (used in) provided by financing activities	(316)	64,896
Net change in cash, cash equivalents and restricted cash	(30,638)	49,318
Cash, cash equivalents and restricted cash, beginning of period	99,542	57,548
Cash, cash equivalents and restricted cash, end of period	68,904	106,866
Supplemental disclosure of cash flow information:
Cash paid for interest	1,297	1,362
Supplemental disclosure of non-cash items:
Equipment purchased under finance lease obligations	709	1,111
Costs incurred, but not paid, in connection with capital expenditures	645	135
Deferred offering costs reclassified to equity	$ 0	$ 28

Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2022

Accounting Policies [Abstract]

Schedule of Concentration of Risk, by Risk Factor and Significant Payer

For each significant payor and customer, revenue as a percentage of total revenue and accounts receivable as a percentage of total accounts receivable are as follows:


	Revenue
	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021

Medicare	62	%	19	%	37	%	19	%
Medicare Advantage	12	%	13	%	15	%	13	%

Blue Shield	*		12	%	*		12	%



*						Less than 10%.


	Accounts Receivable, Net
	September 30, 2022		December 31, 2021

Medicare	53	%	*
Blue Shield	*		19	%
United Healthcare	*		18	%



*						Less than 10%.

Disaggregation of Revenue

The following table includes the Company's revenues as disaggregated by payor and customer category (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2022		2021		2022		2021
Revenue:
Healthcare insurers	$	3,216	$	6,910	$	14,259	$	20,318
Government	9,228		2,330		12,242		6,733
Client(1)	2,046		2,346		5,496		6,738
Other(2)	236		265		729		821
Janssen (SIMPONI®)	—		400		—		1,000
Total revenue	$	14,726	$	12,251	$	32,726	$	35,610

(1)Includes hospitals, other laboratories, etc.

(2)Includes patient self-pay.

Schedule of Restricted Cash and Cash Equivalents

Cash, cash equivalents and restricted cash consist of the following (in thousands):


	September 30, 2022		September 30, 2021		December 31, 2021
Cash and cash equivalents	$	68,704	$	106,766	$	99,442
Restricted cash	200		100		100
	$	68,904	$	106,866	$	99,542

Schedule of Cash and Cash Equivalents

Cash, cash equivalents and restricted cash consist of the following (in thousands):


	September 30, 2022		September 30, 2021		December 31, 2021
Cash and cash equivalents	$	68,704	$	106,766	$	99,442
Restricted cash	200		100		100
	$	68,904	$	106,866	$	99,542

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share

Potentially dilutive securities not included in the calculation of diluted net loss per share because to do so would be anti-dilutive are as follows (in common stock equivalent shares):


	September 30,
	2022	2021


Warrants to purchase common stock	409,108	409,108
Common stock options	1,820,555	2,067,057
Restricted stock units	805,496	403,100
Employee stock purchase plan	17,204	4,130
Total	3,052,363	2,883,395

Summary of Significant Accounting Policies - Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Accounting Policies [Abstract]
Cash and cash equivalents	$ 68,704	$ 99,442	$ 106,766
Restricted cash	200	100	100
Total Cash, Cash Equivalents and Restricted Cash	$ 68,904	$ 99,542	$ 106,866	$ 57,548

Other Financial Information

9 Months Ended

Sep. 30, 2022

Other Financial Information [Abstract]

Other Financial Information

Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consist of the following (in thousands):


	September 30, 2022		December 31, 2021
Diagnostic testing supplies	$	1,364	$	1,091
Prepaid product royalties	42		49
Prepaid maintenance and insurance contracts	1,001		2,008
Other prepaid expenses and other current assets	310		490
Prepaid expenses and other current assets	$	2,717	$	3,638

Property and Equipment, Net

Property and equipment, net consist of the following (in thousands):


	September 30, 2022		December 31, 2021
Furniture and fixtures	$	98	$	83
Laboratory equipment	5,488		4,361
Computer equipment and software	1,461		1,206
Leasehold improvements	3,230		1,151
Construction in progress	2,961		1,855
Total property and equipment	13,238		8,656
Less: accumulated depreciation and amortization	(4,907)		(3,884)
Property and equipment, net	$	8,331	$	4,772

Depreciation and amortization expense for the three months ended September 30, 2022 and 2021 was approximately $0.4 million and $0.3 million, respectively, and for the nine months ended September 30, 2022 and 2021, was approximately $1.0 million and $0.7 million, respectively.

Accrued and Other Current Liabilities

Accrued and other current liabilities consist of the following (in thousands):


	September 30, 2022		December 31, 2021
Accrued payroll and related expenses	$	3,353	$	4,048
Accrued interest	136		139
Accrued purchases of goods and services	1,227		510
Accrued royalties	69		180
Accrued clinical study activity	165		254
Finance lease obligations, current portion	730		587
Refund liability	445		—
Other accrued liabilities	529		1,108
Accrued and other current liabilities	$	6,654	$	6,826

Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2022

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Financial Instrument Measured on a Recurring Basis

The following table sets forth the Company's financial instruments that were measured at fair value on a recurring basis within the fair value hierarchy (in thousands):


	September 30, 2022
	Total		Level 1		Level 2		Level 3
Assets:
Money market funds, included in cash and cash equivalents	$	35,328	$	35,328	$	—	$	—


	December 31, 2021
	Total		Level 1		Level 2		Level 3
Assets:
Money market funds, included in cash and cash equivalents	$	95,761	$	95,761	$	—	$	—

Organization (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash and cash equivalents	$ 68,704		$ 99,442	$ 106,766
Accumulated deficit	$ (241,173)	$ (233,077)	$ (208,140)

Unaudited Condensed Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 68,704	$ 99,442
Accounts receivable, net	10,639	9,654
Prepaid expenses and other current assets	2,717	3,638
Total current assets	82,060	112,734
Property and equipment, net	8,331	4,772
Operating lease right-of-use assets	5,114	0
Goodwill	5,506	5,506
Other assets	586	433
Total assets	101,597	123,445
Current liabilities:
Accounts payable	3,669	2,492
Operating lease liabilities	1,009	0
Accrued and other current liabilities	6,654	6,826
Total current liabilities	11,332	9,318
Borrowings-non-current portion, net of discounts and debt issuance costs	28,008	27,478
Non-current operating lease liabilities	4,766	0
Deferred tax liabilities	306	306
Other non-current liabilities	999	1,407
Total liabilities	45,411	38,509
Commitments and contingencies (Note 6)
Stockholders' equity:
Preferred stock, $0.001 par value; 10,000,000 shares authorized, no shares issued or outstanding as of September 30, 2022 and December 31, 2021	0	0
Common stock, $0.001 par value; 200,000,000 shares authorized as of September 30, 2022 and December 31, 2021; 16,305,475 and 16,164,994 shares issued and outstanding as of September 30, 2022 and December 31, 2021, respectively	16	16
Additional paid-in capital	297,343	293,060
Accumulated deficit	(241,173)	(208,140)
Total stockholders' equity	56,186	84,936
Total liabilities and stockholders' equity	$ 101,597	$ 123,445

Unaudited Condensed Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2022	Dec. 31, 2021
Preferred stock
Par value (in dollars per share)	$ 0.001	$ 0.001
Shares authorized (in shares)	10,000,000	10,000,000
Shares outstanding (in shares)	0	0
Shares issued (in shares)	0	0
Common stock
Par value (in dollars per share)	$ 0.001	$ 0.001
Shares authorized (in shares)	200,000,000	200,000,000
Shares issued (in shares)	16,305,475	16,164,994
Shares outstanding (in shares)	16,305,475	16,164,994