Biocept (BIOCQ) 10-Q 13 Nov 19 2019 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2019	Nov. 08, 2019
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Trading Symbol	BIOC
Entity Registrant Name	BIOCEPT INC
Entity Central Index Key	0001044378
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Common Stock, Shares Outstanding		23,018,235
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	001-36284
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	80-0943522
Entity Address, Address Line One	5810 Nancy Ridge Drive
Entity Address, City or Town	San Diego
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92121
City Area Code	858
Local Phone Number	320-8200
Title of 12(b) Security	Common Stock, par value $.0001 per share
Security Exchange Name	NASDAQ
Entity Shell Company	false
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes

Condensed Balance Sheets

Condensed Balance Sheets - USD ($)	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash	$ 6,539,444	$ 3,423,373
Accounts receivable, net	2,861,659	1,574,325
Inventories, net	687,186	587,222
Prepaid expenses and other current assets	497,121	425,961
Total current assets	10,585,410	6,010,881
Fixed assets, net	1,325,255	2,739,422
Lease right-of-use assets	2,610,249
Total assets	14,520,914	8,750,303
Current liabilities:
Accounts payable	1,834,020	2,039,718
Accrued liabilities	1,846,984	1,928,393
Supplier financings	132,924
Current portion of equipment financings		641,536
Current portion of lease liabilities	1,969,285
Total current liabilities	5,783,213	4,609,647
Non-current portion of equipment financings		985,015
Non-current portion of lease liabilities	1,032,243
Non-current portion of deferred rent		113,122
Total liabilities	6,815,456	5,707,784
Commitments and contingencies (see Note 11)
Shareholders’ equity:
Preferred stock, $0.0001 par value, 5,000,000 authorized; 4,417 shares issued and outstanding at December 31, 2018; and 2,133 shares issued and outstanding at September 30, 2019.
Common stock, $0.0001 par value, 150,000,000 authorized; 4,629,174 issued and outstanding at December 31, 2018; 23,018,235 issued and outstanding at September 30, 2019.	2,302	463
Additional paid-in capital	247,685,038	223,499,634
Accumulated deficit	(239,981,882)	(220,457,578)
Total shareholders’ equity	7,705,458	3,042,519
Total liabilities and shareholders’ equity	$ 14,520,914	$ 8,750,303

Condensed Balance Sheets (Paren

Condensed Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	2,133	4,417
Preferred stock, shares outstanding	2,133	4,417
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	23,018,235	4,629,174
Common stock, shares outstanding	23,018,235	4,629,174

Condensed Statements of Operati

Condensed Statements of Operations and Comprehensive Loss (Unaudited) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Net revenues	$ 1,529,262	$ 761,591	$ 3,744,824	$ 2,390,772
Costs and expenses:
Cost of revenues	2,832,735	2,481,916	8,105,422	7,616,473
Research and development expenses	1,163,546	1,089,746	3,535,116	3,179,612
General and administrative expenses	1,700,380	1,793,720	5,058,525	5,441,354
Sales and marketing expenses	1,462,335	1,404,192	4,451,628	4,473,908
Total costs and expenses	7,158,996	6,769,574	21,150,691	20,711,347
Loss from operations	(5,629,734)	(6,007,983)	(17,405,867)	(18,320,575)
Other income/ (expense):
Interest expense	(62,028)	(63,764)	(187,575)	(230,677)
Warrant inducement and other income (expenses)		23,963	(1,831,116)	(6,037)
Total other income/ (expense):	(62,028)	(39,801)	(2,018,691)	(236,714)
Loss before income taxes	(5,691,762)	(6,047,784)	(19,424,558)	(18,557,289)
Income tax expense				(739)
Net loss and comprehensive loss	(5,691,762)	(6,047,784)	(19,424,558)	(18,558,028)
Deemed dividend related to warrants down round provision		(636,370)	(99,743)	(636,370)
Net loss attributable to common shareholders	$ (5,691,762)	$ (6,684,154)	$ (19,524,301)	$ (19,194,398)
Weighted-average shares outstanding used in computing net loss per share attributable to common shareholders:
Basic	23,018,235	2,767,440	17,807,298	2,322,749
Diluted	23,018,235	2,759,614	17,807,298	2,320,111
Net loss per common share:
Basic	$ (0.25)	$ (2.42)	$ (1.10)	$ (8.26)
Diluted	$ (0.25)	$ (2.42)	$ (1.10)	$ (8.27)

Condensed Statements of Shareho

Condensed Statements of Shareholders' Equity - USD ($)	Total	August 2018 Rights Offering [Member]	September 2018 Registered Direct Offering [Member]	January 2019 Financing Transaction [Member]	February 2019 Financing Transaction [Member]	January 2019 Financing Transaction Overallotment [Member]	March 2019 Financing Transaction [Member]	January 2018 financing transaction [Member]	Common Stock [Member]	Common Stock [Member]September 2018 Registered Direct Offering [Member]	Common Stock [Member]January 2019 Financing Transaction [Member]	Common Stock [Member]February 2019 Financing Transaction [Member]	Common Stock [Member]January 2019 Financing Transaction Overallotment [Member]	Common Stock [Member]March 2019 Financing Transaction [Member]	Common Stock [Member]January 2018 financing transaction [Member]	SeriesA Convertible Preferred Stock [Member]	SeriesA Convertible Preferred Stock [Member]August 2018 Rights Offering [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member]August 2018 Rights Offering [Member]	Additional Paid-in Capital [Member]September 2018 Registered Direct Offering [Member]	Additional Paid-in Capital [Member]January 2019 Financing Transaction [Member]	Additional Paid-in Capital [Member]February 2019 Financing Transaction [Member]	Additional Paid-in Capital [Member]January 2019 Financing Transaction Overallotment [Member]	Additional Paid-in Capital [Member]March 2019 Financing Transaction [Member]	Additional Paid-in Capital [Member]January 2018 financing transaction [Member]	Accumulated Deficit [Member]
Beginning balance at Dec. 31, 2017	$ 1,296,034								$ 118									$ 196,545,523								$ (195,249,607)
Beginning balance, shares at Dec. 31, 2017									1,181,179
Stock-based compensation expense	225,263																	225,263
Shares and warrants issued, net of issuance costs								$ 13,342,821							$ 110										$ 13,342,711
Shares and warrants issued, net of issuance costs, shares															1,095,153
Adjustment for presentation after reverse stock split									$ 6,576									(6,576)
Net loss	(6,357,143)																									(6,357,143)
Ending balance at Mar. 31, 2018	8,506,975								$ 6,804									210,106,921								(201,606,750)
Ending balance, shares at Mar. 31, 2018									2,276,332
Beginning balance at Dec. 31, 2017	1,296,034								$ 118									196,545,523								(195,249,607)
Beginning balance, shares at Dec. 31, 2017									1,181,179
Deemed dividends related warrants down round provision	636,370
Net loss	(18,558,028)
Ending balance at Sep. 30, 2018	8,938,408								$ 394							$ 1		223,382,018								(214,444,005)
Ending balance, shares at Sep. 30, 2018									3,937,226							7,005
Beginning balance at Dec. 31, 2017	1,296,034								$ 118									196,545,523								(195,249,607)
Beginning balance, shares at Dec. 31, 2017									1,181,179
Net loss	(24,600,000)
Ending balance at Dec. 31, 2018	3,042,519								$ 463									223,499,634								(220,457,578)
Ending balance, shares at Dec. 31, 2018									4,629,174							4,417
Beginning balance at Mar. 31, 2018	8,506,975								$ 6,804									210,106,921								(201,606,750)
Beginning balance, shares at Mar. 31, 2018									2,276,332
Stock-based compensation expense	173,694																	173,694
Shares issued for restricted stock units									$ 19									(19)
Shares issued for restricted stock units, shares									5,834
Net loss	(6,153,101)																									(6,153,101)
Ending balance at Jun. 30, 2018	2,527,568								$ 6,823									210,280,596								(207,759,851)
Ending balance, shares at Jun. 30, 2018									2,282,166
Stock-based compensation expense	113,072																	113,072
Shares and warrants issued, net of issuance costs		$ 10,097,878	$ 2,247,674							$ 64							$ 1		$ 10,097,877	$ 2,247,610
Shares and warrants issued, net of issuance costs, shares										642,438							11,587
Deemed dividends related warrants down round provision	636,370																	636,370								(636,370)
Shares issued upon conversion of preferred stock									$ 101									(101)
Shares issued upon conversion of preferred stock, shares									1,012,622							(4,582)
Common stock reclassification									$ (6,594)									6,594
Net loss	(6,047,784)																									(6,047,784)
Ending balance at Sep. 30, 2018	8,938,408								$ 394							$ 1		223,382,018								(214,444,005)
Ending balance, shares at Sep. 30, 2018									3,937,226							7,005
Beginning balance at Dec. 31, 2018	3,042,519								$ 463									223,499,634								(220,457,578)
Beginning balance, shares at Dec. 31, 2018									4,629,174							4,417
Stock-based compensation expense	102,459																	102,459
Shares issued upon exercise of common stock warrants	4,748								$ 1									4,747
Shares issued upon exercise of common stock warrants, shares									5,985
Shares and warrants issued, net of issuance costs				$ 2,032,311	$ 6,602,735	$ 592,306	$ 7,553,793				$ 99	$ 625	$ 54	$ 595							$ 2,032,212	$ 6,602,110	$ 592,252	$ 7,553,198
Shares and warrants issued, net of issuance costs, shares											990,000	6,250,000	538,867	5,950,000
Deemed dividends related warrants down round provision																		99,743								(99,743)
Shares issued upon conversion of preferred stock									$ 50									(50)
Shares issued upon conversion of preferred stock, shares									503,438							(2,278)
Net loss	(5,916,787)																									(5,916,787)
Ending balance at Mar. 31, 2019	14,014,084								$ 1,887									240,486,305								(226,474,108)
Ending balance, shares at Mar. 31, 2019									18,867,464							2,139
Beginning balance at Dec. 31, 2018	3,042,519								$ 463									223,499,634								(220,457,578)
Beginning balance, shares at Dec. 31, 2018									4,629,174							4,417
Deemed dividends related warrants down round provision	99,743
Net loss	(19,424,558)
Ending balance at Sep. 30, 2019	7,705,458								$ 2,302									247,685,038								(239,981,882)
Ending balance, shares at Sep. 30, 2019									23,018,235							2,133
Beginning balance at Mar. 31, 2019	14,014,084								$ 1,887									240,486,305								(226,474,108)
Beginning balance, shares at Mar. 31, 2019									18,867,464							2,139
Stock-based compensation expense	224,641																	224,641
Shares issued upon exercise of common stock warrants	4,845,722								$ 415									4,845,307
Shares issued upon exercise of common stock warrants, shares									4,149,445
Shares issued upon conversion of preferred stock, shares									1,326							(6)
Warrant inducement expense	1,831,116																	1,831,116
Net loss	(7,816,012)																									(7,816,012)
Ending balance at Jun. 30, 2019	13,099,551								$ 2,302									247,387,369								(234,290,120)
Ending balance, shares at Jun. 30, 2019									23,018,235							2,133
Stock-based compensation expense	297,669																	297,669
Net loss	(5,691,762)																									(5,691,762)
Ending balance at Sep. 30, 2019	$ 7,705,458								$ 2,302									$ 247,685,038								$ (239,981,882)
Ending balance, shares at Sep. 30, 2019									23,018,235							2,133

Condensed Statements of Cash Fl

Condensed Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended				9 Months Ended		12 Months Ended
	Sep. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Cash Flows from Operating Activities
Net loss	$ (5,691,762)	$ (5,916,787)	$ (6,047,784)	$ (6,357,143)	$ (19,424,558)	$ (18,558,028)	$ (24,600,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization					691,191	580,366
Amortization of right-of-use assets					(113,419)
Inventory reserve					20,277	(92,488)
Stock-based compensation					624,769	512,029
Warrant inducement expense					1,831,116
Non-cash interest expense related to credit facility and other financing activities						29,425
Increase/(decrease) in cash resulting from changes in:
Accounts receivable, net					(1,287,334)	(283,028)
Inventory					(120,241)	9,692
Prepaid expenses and other current assets					322,299	277,720
Accounts payable					(198,400)	413,562
Accrued liabilities					76,932	497,119
Accrued interest						(241,034)
Deferred rent						(82,329)
Net cash used in operating activities					(17,577,368)	(16,936,994)
Cash Flows from Investing Activities:
Purchases of fixed assets					(297,877)	(145,253)
Net cash used in investing activities					(297,877)	(145,253)
Cash Flows from Financing Activities:
Net proceeds from issuance of common stock and warrants					16,779,772	25,688,205
Proceeds from exercise of common stock warrants					2,513,172	0
Proceeds from warrant exercise inducement, net					2,337,298
Payments on finance leases	(101,139)				(378,389)	(160,111)
Payments on supplier and other third-party financings					(260,537)	(438,290)
Payments on credit facility						(1,197,968)
Net cash provided by financing activities					20,991,316	23,891,836
Net increase in Cash					3,116,071	6,809,589
Cash at Beginning of Period		$ 3,423,373		$ 2,146,611	3,423,373	2,146,611	2,146,611
Cash at End of Period	$ 6,539,444		$ 8,956,200		6,539,444	8,956,200	$ 3,423,373
Cash paid during the period for:
Interest					$ 187,574	379,587
Income taxes						$ 739

Condensed Statements of Cash _2

Condensed Statements of Cash Flows (Unaudited) (Parenthetical) - USD ($)	Sep. 20, 2018	Aug. 13, 2018	Jan. 30, 2018	May 31, 2019	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Cancelled insurance premiums previously financed through third-parties, remaining principal outstanding balance							$ 31,000
Financed insurance premium through third party financing							393,000	$ 488,000
Financed insurance premium through third party financing, new policies							80,000
Fixed assets purchased under capital lease obligations							583,000	270,000
Purchases of fixed assets							67,000	$ 55,000	$ 25,000	$ 31,000
Public offering, number of common stock and warrants issued	642,438
Stock price	$ 3.285
Exercise price of unregistered warrants		$ 4.53
Class of warrant or rights, term		5 years	5 years
Issuance of unregistered warrants to purchase shares of common stock, grant date fair value	$ 2,000,000	$ 8,400,000	$ 9,700,000
Offering fees and costs recorded within common stock issuance costs as an offset to additional paid in capital	300,000	$ 1,400,000	1,400,000
Aggregate units sold under right offering		11,587
Warrant exercisable for share of common stock		1
Gross proceeds from offering	$ 2,500,000	$ 11,600,000
Preferred stock converted to shares of common stock					1,012,622	1,012,622		1,012,622
Deemed dividend related to warrants down round provision			$ 99,000		$ 636,000	$ 636,370	99,743	$ 636,370
Operating lease, right-of-use asset							1,035,210
Operating lease liability							1,193,255
Lease right-of-use assets							1,575,039
Number of common stock warrant exercised				4,100,000
Proceeds from exercise of common stock warrants				$ 4,800,000			$ 2,513,172	$ 0
Warrant Inducement Transaction [Member]
Number of common stock warrant exercised				2,100,000
Proceeds from exercise of common stock warrants				$ 2,300,000
Pre-funded Warrants [Member]
Issuance of warrants to purchase shares of common stock	120,000
Exercise price of unregistered warrants	$ 3.275
Change in exercise price of warrants	$ 0.01
Warrant [Member]
Aggregate warrants sold under right offering		2,549,140
Proceeds from exercise of common stock warrants				$ 2,500,000
Series A Preferred Stock [Member]
Shares issued in offering		11,587
Shares converted						4,582
Maximum [Member]
Exercise price of unregistered warrants				$ 1.20
Maximum [Member] | Pre-funded Warrants [Member]
Issuance of warrants to purchase shares of common stock	120,000
Minimum [Member]
Exercise price of unregistered warrants				$ 1.25
Follow-on Public Offering [Member]
Public offering, number of common stock and warrants issued			1,095,153
Stock price			$ 13.50
Exercise price of unregistered warrants	$ 3.16	$ 4.53	$ 1.20
Class of warrant or rights, term	5 years	5 years	5 years
Issuance of unregistered warrants to purchase shares of common stock, grant date fair value			$ 9,700,000
Proceeds from issuance of common stock, net of issuance costs			13,300,000
Proceeds from exercise of common stock warrants			$ 0
Follow-on Public Offering [Member] | Maximum [Member]
Issuance of warrants to purchase shares of common stock			1,095,153
Private Placement [Member]
Exercise price of unregistered warrants	$ 3.16
Class of warrant or rights, term	5 years
Warrant exercisable for share of common stock	1

The Company, Business Activitie

The Company, Business Activities and Basis of Presentation	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
The Company, Business Activities and Basis of Presentation	1. The Company, Business Activities and Basis of Presentation The Company and Business Activities The Company was founded in California in May 1997 and effected a reincorporation to Delaware in July 2013. The Company is an early stage molecular oncology diagnostics company that develops and commercializes proprietary circulating tumor cell, or CTC, and circulating tumor DNA, or ctDNA, assays utilizing a standard blood sample, or liquid biopsy. The Company’s current and planned assays are intended to provide information to aid healthcare providers to identify specific oncogenic alterations that may qualify a subset of cancer patients for targeted therapy at diagnosis, progression or for monitoring in order to identify specific resistance mechanisms. Sometimes traditional procedures, such as surgical tissue biopsies, result in tumor tissue that is insufficient and/or unable to provide the molecular subtype information necessary for clinical decisions. The Company’s assays, performed on blood, have the potential to provide more contemporaneous information on the characteristics of a patient’s disease when compared with tissue biopsy and radiographic imaging. Additionally, commencing in October 2017, the Company’s pathology partnership program, branded as Empower TC TM The Company operates a clinical laboratory that is CLIA-certified (under the Clinical Laboratory Improvement Amendment of 1988) and CAP-accredited (by the College of American Pathologists), and manufactures cell enrichment and extraction microfluidic channels, related equipment and certain reagents to perform the Company’s diagnostic assays in a facility located in San Diego, California. CLIA certification and accreditation are required before any clinical laboratory may perform testing on human specimens for the purpose of obtaining information for the diagnosis, prevention, treatment of disease, or assessment of health. The assays the Company offers are classified as laboratory developed tests under the CLIA regulations. Basis of Presentation The accompanying unaudited condensed financial statements and notes are prepared in accordance with accounting principles generally accepted in the United States of America, or GAAP, and on the basis that the Company will continue as a going concern (see Note 2). The accompanying unaudited condensed financial statements and notes do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classification of liabilities that may result from the possible inability of the Company to continue as a going concern. On July 6, 2018, the Company’s stockholders approved, and the Company filed, an amendment to the Company’s Certificate of Amendment of Certificate of Incorporation to effect a one-for-thirty reverse stock split of the Company’s outstanding common stock. As such, all references to share and per share amounts in these unaudited condensed financial statements and accompanying notes have been retroactively restated to reflect the one-for-thirty reverse stock split, except for the authorized number of shares of the Company’s common stock of 150,000,000 The unaudited condensed financial statements included in this Form 10-Q have been prepared in accordance with the U.S. Securities and Exchange Commission, or SEC, instructions for Quarterly Reports on Form 10-Q. Accordingly, the condensed financial statements are unaudited and do not contain all the information required by GAAP to be included in a full set of financial statements. The balance sheet at December 31, 2018 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by GAAP for a complete set of financial statements. The audited financial statements for the year ended December 31, 2018, filed with the U.S. Securities and Exchange Commission, or SEC, with our Annual Report on Form 10-K on March 29, 2019 include a summary of our significant accounting policies and should be read in conjunction with this Form 10-Q. In the opinion of management, all material adjustments necessary to present fairly the results of operations for such periods have been included in this Form 10-Q. All such adjustments are of a normal recurring nature. The results of operations for interim periods are not necessarily indicative of the results of operations for the entire year. Certain prior period balances have been reclassified to conform to the current period presentation. Such reclassifications had no effect on net loss. Revenue Recognition and Accounts Receivable The Company's commercial revenues are generated from diagnostic services provided to patient’s physicians and billed to third-party insurance payers such as managed care organizations, Medicare and Medicaid and patients for any deductibles, coinsurance or copayments that may be due. Commencing on January 1, 2018, the Company recognizes revenue in accordance with ASC 606, Revenue from Contracts with Customers, or ASC 606, which requires that an entity recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled to in exchange for those goods or services. The Company adopted the provisions of ASC 606 using the modified retrospective application method applied to all contracts, which did not impact amounts previously reported by the Company, nor did it require a cumulative effect adjustment upon adoption, as the Company’s method of recognizing revenue under ASC 606 was analogous to the method utilized immediately prior to adoption. Accordingly, there is no need for the Company to disclose the amount by which each financial statement line item was affected as a result of applying the new standard and an explanation of significant changes. Contracts For its commercial revenues, while the Company markets directly to physicians, its customer is the patient. Patients do not enter into direct agreements with the Company, however, a patient’s insurance coverage requirements would dictate whether or not any portion of the cost of the tests would be patient responsibility. Accordingly, the Company establishes contracts with commercial insurers in accordance with customary business practices, as follows: • Approval of a contract is established via the order and accession, which are submitted by the patient’s physician. • The Company is obligated to perform its diagnostic services upon receipt of a sample from a physician, and the patient and/or applicable payer are obligated to reimburse the Company for services rendered based on the patient’s insurance benefits. • Payment terms are a function of a patient’s existing insurance benefits, including the impact of coverage decisions with CMS and applicable reimbursement contracts established between the Company and payers, unless the patient is a self-pay patient, whereby the Company bills the patient directly after the services are provided. • On ce the Company delivers a patient’s assay result to the ordering physician, the contract with a patient has commercial substance, as the Company is legally able to collect payment and bill an insurer and/or patient, regardless of payer contract status or patient insurance benefit status. • Consideration associated with commercial revenues is considered variable and constrained until fully adjudicated, with net revenues recorded to the extent that it is probable that a significant reversal will not occur. The Company’s development services revenues are supported by contractual agreements and generated from assay development services provided to entities, as well as certain other diagnostic services provided to physicians, and revenues are recognized upon delivery of the performance obligations in the contract. Performance Obligations A performance obligation is a promise in a contract to transfer a distinct good or service, or a bundle of goods or services, to the customer. For its commercial and development services revenues, the Company’s contracts have a single performance obligation, which is satisfied upon rendering of services, which culminates in the delivery of a patient’s assay result(s) to the ordering physician or entity. The duration of time between accession receipt and delivery of a valid assay result to the ordering physician or entity is typically less than two weeks. Accordingly, the Company elected the practical expedient and therefore, does not disclose the value of unsatisfied performance obligations. Transaction Price The transaction price is the amount of consideration that the Company expects to collect in exchange for transferring promised goods or services to a customer, excluding amounts collected on behalf of third parties, such as sales taxes. The consideration expected from a contract with a customer may include fixed amounts, variable amounts, or both. The Company’s gross commercial revenues billed, and corresponding gross accounts receivable, are subject to estimated deductions for such allowances and reserves to arrive at reported net revenues, which relate to differences between amounts billed and corresponding amounts estimated to be subsequently collected, and is deemed to be variable although the variability is not explicitly stated in any contract. Rather, the implied variability is due to several factors, such as the payment history or lack thereof for third-party payers, reimbursement rate changes for contracted and non-contracted payers, any patient co-payments, deductibles or compliance incentives, the existence of secondary payers and claim denials. The Company estimates the The Company limits the amount of variable consideration included in the transaction price to the unconstrained portion of such consideration. Revenue is recognized up to the amount of variable consideration that is not subject to a significant reversal until additional information is obtained or the uncertainty associated with the additional payments or refunds is subsequently resolved. Differences between original estimates and subsequent revisions, including final settlements, represent changes in the estimate of variable consideration and are included in the period in which such revisions are made. The Company monitors its estimates of transaction price to depict conditions that exist at each reporting date. If the Company subsequently determines that it will collect more consideration than it originally estimated for a contract with a customer, it will account for the change as an increase in the estimate of the transaction price in the period identified as an increase to revenue. Similarly, if the Company subsequently determines that the amount it expects to collect from a customer is less than it originally estimated, it will generally account for the change as a decrease in the estimate of the transaction price as a decrease to revenue, provided that such downward adjustment does not result in a significant reversal of cumulative revenue recognized. Revenue recognized from changes in transaction prices was not significant during the three and nine months ended September 30, 2018 and 2019. Allocate Transaction Price For the Company’s commercial revenues, the entire transaction price is allocated to the single performance obligation contained in a contract with a customer. For the Company’s development services revenues, the contracted transaction price is allocated to each single performance obligation contained in a contract with a customer as performed. Point-in-time Recognition The Company’s single performance obligation is satisfied at a point in time, and that point in time is defined as the date a patient’s successful assay result is delivered to the patient’s ordering physician or entity. The Company considers this date to be the time at which the patient obtains control of the promised diagnostic assay service. Contract Balances The timing of revenue recognition, billings and cash collections results in accounts receivable recorded in the Company’s condensed balance sheets. Generally, billing occurs subsequent to delivery of a patient’s test result to the ordering physician or entity, resulting in an account receivable. Practical Expedients The Company does not adjust the transaction price for the effects of a significant financing component, as at contract inception, the Company expects the collection cycle to be one year or less. The Company expenses sales commissions when incurred because the amortization period is one year or less, which are recorded within sales and marketing expenses. The Company incurs certain other costs that are incurred regardless of whether a contract is obtained. Such costs are primarily related to legal services and patient communications. These costs are expensed as incurred and recorded within general and administrative expenses. Disaggregation of Revenue and Concentration of Risk The composition of the Company’s net revenues recognized during the three and nine months ended September 30, 2018 and 2019, disaggregated by source and nature, are as follows: For the three months ended September 30, For the nine months ended September 30, 2018 2019 2018 2019 Net revenues from contracted payers* $ 325,097 $ 476,101 $ 1,019,857 $ 1,447,421 Net revenues from non-contracted payers 373,018 956,140 1,201,869 2,080,018 Development services revenues 63,476 37,981 159,606 125,169 Kits and Blood Collection Tubes (BCT) — 59,040 9,440 92,216 Total net revenues $ 761,591 $ 1,529,262 $ 2,390,772 $ 3,744,824 *Includes Medicare and Medicare Advantage, as reimbursement amounts are fixed. For the three months ended September 30, For the nine months ended September 30, 2018 2019 2018 2019 Net commercial revenues recognized upon delivery $ 698,115 $ 1,432,241 $ 2,221,726 $ 3,527,439 Development services revenues recognized upon delivery 63,476 37,981 159,606 125,169 Kits and Blood Collection Tubes (BCT) — 59,040 9,440 92,216 Total net revenues $ 761,591 $ 1,529,262 $ 2,390,772 $ 3,744,824 Concentrations of credit risk with respect to revenues are primarily limited to geographies to which the Company provides a significant volume of its services, and to specific third-party payers of the Company’s services such as Medicare, insurance companies, and other third-party payers. The Company’s client base consists of many geographically dispersed clients diversified across various customer types. The Company's third-party payers that represent more than 10% of total net revenues in any period presented, as well as their related net revenue amount as a percentage of total net revenues, during the three and nine months ended September 30, 2018 and 2019 were as follows: For the three months ended September 30, For the nine months ended September 30, 2018 2019 2018 2019 Medicare and Medicare Advantage 40 % 32 % 39 % 40 % Blue Cross Blue Shield 9 % 25 % 14 % 20 % United Healthcare 6 % 8 % 15 % 9 % The Company's third-party payers that represent more than 10% of total net accounts receivable, and their related net accounts receivable balance as a percentage of total net accounts receivable, at December 31, 2018 and September 30, 2019 were as follows: December 31, 2018 September 30, 2019 Blue Cross Blue Shield 22 % 25 % Medicare and Medicare Advantage 17 % 17 % United Healthcare 15 % 13 % Recent Accounting Pronouncements In February 2016, the FASB issued authoritative guidance, which changes several aspects of the accounting for leases, including the requirement that all leases with durations greater than twelve months be recognized on the balance sheet. The guidance is effective for annual and interim reporting periods in fiscal years beginning after December 15, 2018. Effective January 1, 2019, the Company adopted the guidance and elected the optional transition method to account for the impact of the adoption with a cumulative-effect adjustment in the period of adoption and did not restate prior periods. The Company also elected the practical expedient package as permitted under the transition guidance. As of January 1, 2019, the Company recorded a right-of-use asset and liability upon adoption of the guidance (See Note 7). In August 2017, the FASB issued authoritative guidance that expands and refines hedge accounting for both nonfinancial and financial risk components and align the recognition and presentation of the effects of the hedging instrument and the hedged item in the financial statements. This guidance is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early application is permitted. The Company adopted this guidance for the fiscal year beginning on January 1, 2019 and determined that the adoption of this guidance does not have a material impact on its financial statements or disclosures because the Company does not currently hold any financial instruments accounted for as a hedging activity. In February 2018, the FASB issued authoritative guidance allowing a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from a tax bill, “H.R.1, An Act to Provide for Reconciliation Pursuant to Titles II and V of the Concurrent Resolution on the Budget for Fiscal Year 2018,” or the Tax Cuts and Jobs Act, enacted on December 22, 2017. These amendments eliminate the stranded tax effects resulting from the Tax Cuts and Jobs Act. However, because these amendments only relate to the reclassification of the income tax effects of the Tax Cuts and Jobs Act, the underlying guidance that requires that the effect of a change in tax laws or rates be included in income from continuing operations is not affected. This guidance also requires certain disclosures about stranded tax effects. This guidance is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption is permitted. The Company adopted this guidance for the fiscal year beginning on January 1, 2019 which did not have a material impact on its financial statements or disclosures because the Company does not currently maintain any stranded tax effects in accumulated other comprehensive income. In June 2018, the FASB issued authoritative guidance simplifying the accounting for nonemployee stock-based compensation and largely aligning such compensation with the accounting requirements for employee stock-based awards. For public companies, this guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within that fiscal year. The Company adopted this guidance for the fiscal year beginning on January 1, 2019 and determined that the adoption of this guidance does not have a material impact on its financial statements or disclosures. In November 2018, the FASB issued authoritative guidance clarifying the interaction between Collaborative Arrangements (Topic 808) and Revenue from Contracts with Customers (Topic 606) to address diversity in practice related to how companies account for collaborative arrangements. For public companies, this guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within that fiscal year. Early adoption is permitted, but no earlier than an entity’s adoption date of Revenue from Contracts with Customers (Topic 606). The Company currently intends to adopt this guidance upon the effective date and does not anticipate that the adoption of this guidance will have a material impact on its financial statements or disclosures.

Liquidity and Going Concern Unc

Liquidity and Going Concern Uncertainty	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
Liquidity and Going Concern Uncertainty	2. Liquidity and Going Concern Uncertainty As of September 30, 2019, cash totaled $6.5 million and the Company had an accumulated deficit of $240.0 million. While the Company is currently in the commercialization stage of operations, the Company has not yet achieved profitability and anticipates that it will continue to incur net losses for the foreseeable future. Historically, the Company’s principal sources of cash have included proceeds from the issuance of common and preferred stock, proceeds from the exercise of warrants to purchase common stock, proceeds from the issuance of debt, and revenues from laboratory services. The Company’s principal uses of cash have included cash used in operations, payments relating to purchases of property and equipment and repayments of borrowings. The Company expects that the principal uses of cash in the future will be for continuing operations, hiring of sales and marketing personnel and increased sales and marketing activities, funding of research and development, capital expenditures, and general working capital requirements. The Company expects that, as revenues grow, sales and marketing and research and development expenses will continue to grow, albeit at a slower rate and, as a result, the Company will need to generate significant growth in net revenues to achieve and sustain income from operations. On January 30, 2018, the Company received net cash proceeds of approximately $13.3 million from the closing of a follow-on public offering of 1,095,153 shares of its common stock and warrants to purchase up to an aggregate of 1,095,153 shares of its common stock at a combined offering price of $13.50 per unit. Subsequent to the closing of this offering, no additional cash proceeds have been received from the exercise of warrants sold in this offering, with approximately $1.3 million in gross warrant proceeds remaining outstanding and available to be exercised at $1.20 per share, which is subject to down round adjustment, until their expiration in January 2023. Pursuant to the down round adjustment feature of the January 2018 warrants, the exercise price of these warrants was adjusted to the $1.20 offering price per share in the February 2019 financing transaction. In May 2018, the SEC declared effective a shelf registration statement filed by the Company, which expires in May 2021. The shelf registration statement allows the Company to issue any combination of its common stock, preferred stock, debt securities and warrants from time to time for an aggregate initial offering price of up to $50 million, subject to certain limitations for so long as its public float is less than $75 million. On August 13, 2018, the Company completed a rights offering pursuant to an effective registration statement. Pursuant to the rights offering, the Company sold an aggregate of 11,587 units consisting of an aggregate of 11,587 shares of Series A Preferred Stock convertible into 471,393 shares of its common stock and 2,549,140 warrants, with each warrant exercisable for one share of its common stock at an exercise price of $4.53 per share, resulting in net proceeds to the Company of approximately $10.1 million, after deducting expenses relating to the rights offering, including dealer-manager fees and expenses, and excluding any proceeds received upon exercise of any warrants. On September 20, 2018, the Company completed a registered offering of 642,438 shares of the Company’s common stock and pre-funded warrants to purchase up to an aggregate of 120,000 shares of its common stock. The shares were sold at a purchase price of $3.285 per share and the pre-funded warrants were sold at a purchase price of $3.275 per pre-funded warrant which represents the per share purchase price for the shares less the $0.01 per share exercise price for each such pre-funded warrant. The net proceeds to the Company from the offering were approximately $2.2 million, after deducting expenses related to the offering including dealer-manager fees and expenses, and excluding any proceeds received upon exercise of any warrants On January 18, 2019, the Company completed a registered offering of 990,000 shares of the Company’s common stock. The shares were sold at a purchase price of $2.25 per share and the net proceeds to the Company from this offering were approximately $2.0 million, after deducting expenses related to the offering including dealer-manager fees and expenses. On February 12, 2019, the Company received net cash proceeds of approximately $6.6 million from the closing of a follow-on public offering of 6,250,000 shares of its common stock and warrants to purchase up to an aggregate of 6,250,000 shares of its common stock at a combined offering price of $1.20 per unit. In addition, the Company sold warrants to purchase up to an aggregate of 937,500 shares of the Company’s common stock in connection with the partial exercise of the over-allotment option granted to the underwriters. Upon closing of the transaction, warrants to purchase 915,000 shares were issued pursuant to the placement agents’ partial exercise of their overallotment. On March 19, 2019, the Company received net cash proceeds of approximately $7.5 million as a result of completing a registered direct offering of 5,950,000 shares at a negotiated purchase price of $1.37 per share. In May 2019, the Company received net proceeds of approximately $2.3 million related to the May 2019 Warrant Exercise Inducement Offering as well as an additional $2.5 million from other warrant exercises. The warrants exercised had exercise prices ranging from $1.20 to $1.25 per share and the total number of shares of common stock issued upon exercises both in connection with the Warrant Exercise Inducement Offering and other warrant exercises was approximately 4.2 million shares. Management’s Plan to Continue as a Going Concern In order to continue as a going concern, the Company will need, among other things, additional capital resources. Until the Company can generate significant cash from operations, including assay revenues, management’s plans to obtain such resources for the Company include proceeds from offerings of the Company’s equity securities or debt, cash received from the exercise of outstanding common stock warrants, or transactions involving product development, technology licensing or collaboration. Management can provide no assurances that any sources of a sufficient amount of financing will be available to the Company on favorable terms, if at all.

Sales of Equity Securities

Sales of Equity Securities	9 Months Ended
	Sep. 30, 2019
Equity [Abstract]
Sales of Equity Securities	3. Sales of Equity Securities On January 30, 2018, the Company received net cash proceeds of approximately $13.3 million from the closing of a follow-on public offering of 1,095,153 shares of its common stock and warrants to purchase up to an aggregate of 1,095,153 shares of its common stock at a combined offering price of $13.50 per unit, with $1.4 million of costs directly associated with the offering recorded as an offset to additional paid-in capital under applicable accounting guidance. The warrants sold in this offering have an exercise price of $1.20 per share, which is subject to down round adjustment, are exercisable immediately and expire five years from the date of issuance. The aggregate estimated grant date fair value of $9.7 million was recorded as an offset to additional paid-in-capital upon the closing of this offering (see Note 4). In May 2018, the SEC declared effective a shelf registration statement filed by the Company, which expires in May 2021. The shelf registration statement allows the Company to issue any combination of our common stock, preferred stock, debt securities and warrants from time to time for an aggregate initial offering price of up to $50 million, subject to certain limitations for so long as our public float is less than $75 million. On August 13, 2018, the Company completed a rights offering. Pursuant to the rights offering, the Company sold an aggregate of 11,587 units consisting of an aggregate of 11,587 shares of Series A Preferred Stock and 2,549,140 warrants, with each warrant exercisable for one share of our common stock at an exercise price of $4.53 per share, resulting in net proceeds to the Company of approximately $10.1 million, after deducting expenses relating to the rights offering, including dealer-manager fees and expenses, and excluding any proceeds received upon exercise of any warrants. Each share of Series A Preferred Stock will be convertible, at the Company’s option at any time on or after the first anniversary of the closing of the Rights Offering or at the option of the holder at any time, into the number of shares of the Company’s common stock, par value $0.0001 per share determined by dividing the $1,000 stated value per share of the Series A Preferred Stock by a conversion price of $4.53 per share. In addition, the conversion price per share is subject to adjustment for stock dividends, distributions, subdivisions, combinations or reclassifications. Holders of Series A Preferred Stock shall be entitled to receive dividends (on an as-if-converted-to-common-stock basis) in the same form as dividends actually paid on shares of the common stock when, as and if such dividends are paid on shares of common stock. The Series A Preferred Stock have no voting rights. Upon the Company’s liquidation, dissolution or winding-up, whether voluntary or involuntary, holders of Series A Preferred Stock will be entitled to receive out of the assets, whether capital or surplus, of the Company the same amount that a holder of common stock would receive if the Series A Preferred Stock were fully converted (disregarding for such purpose any conversion limitations thereunder) to common stock, which amounts shall be paid pari passu with all holders of common stock. The Company is not obligated to redeem or repurchase any shares of Series A Preferred Stock. On September 20, 2018, the Company completed an offering of 642,438 shares of the Company’s common stock and pre-funded warrants to purchase up to an aggregate of 120,000 shares of its common stock. The shares were sold at a purchase price of $3.285 per share and the pre-funded warrants were sold at a purchase price of $3.275 per pre-funded warrant which represents the per share purchase price for the shares less the $0.01 per share exercise price for each such pre-funded warrant. The net proceeds to the Company from this offering were approximately $2.2 million, after deducting expenses related to the offering including dealer-manager fees and expenses, and excluding any proceeds received upon exercise of any warrants On January 18, 2019, the Company completed an offering of 990,000 shares of the Company’s common stock. The shares were sold at a purchase price of $2.25 per share and the net proceeds to the Company from this offering were approximately $2.0 million, after deducting expenses related to the offering including dealer-manager fees and expenses. On February 12, 2019, the Company received net cash proceeds of approximately $6.6 million as a result of the closing of a follow-on public offering of 6,250,000 shares of its common stock and warrants to purchase up to an aggregate of 6,250,000 shares of its common stock at a combined offering price of $1.20 per unit. All warrants sold in this offering have an exercise price of $1.20 per share, are exercisable immediately and expire five years from the date of issuance. In addition, the Company sold warrants to purchase up to an aggregate of 937,500 shares of the Company’s common stock in connection with the partial exercise of the over-allotment option granted to the underwriters. Upon closing of the transaction, warrants to purchase 915,000 shares were issued pursuant to the placement agents’ partial exercise of their overallotment. Pursuant to the down round adjustment feature of the January 2018 warrants, the exercise price of these warrants was adjusted to the $1.20 price per share offering price in the February 2019 financing transaction. On March 19, 2019, the Company received net cash proceeds of approximately $7.5 million as a result of completing a registered direct offering of 5,950,000 shares at a negotiated purchase price of $1.37 per share. In addition, in a concurrent private placement, the Company issued to purchasers a warrant to purchase one share of the Company’s common stock for each share purchased for cash in the offering. All warrants issued in this offering have an exercise price of $1.25 per share, are exercisable immediately upon issuance and expire 5.5 years following the date of issuance. In May 2019, the Company received cash proceeds of approximately $2.5 million from the exercise of 2,086,479 February 2019 warrants at $1.20 per share. On May 28, 2019, the Company entered into Warrant Exercise Agreements, or the Exercise Agreements, with certain of the holders of its existing warrants, or the Exercising Holders. Pursuant to the Exercise Agreements, the Exercising Holders and the Company agreed that, subject to any applicable beneficial ownership limitations, the Exercising Holders would cash exercise up to 20% of their Existing Warrants, or the Investor Warrants, into shares of common stock underlying such Existing Warrants, or the Exercised Shares. In order to induce the Exercising Holders to cash exercise the Investor Warrants, the Exercise Agreements provided for the issuance of new warrants, or the New Warrants, with such New Warrants to be issued in an amount equal to 75% of the number of Exercised Shares underlying any Investor Warrants that was cash exercised by July 15, 2019. The New Warrants were exercisable upon issuance and terminate on the date that is five-years and six-months following the initial exercise date. The New Warrants have an exercise price per share of $1.31. A total of 2,062,966 Investor Warrants were exercised contemporaneously with the execution of the Exercise Agreements resulting in total proceeds to the Company of $2.3 million, net of investment banking fees. The warrants issued in connection with the Exercise Agreement were considered inducement warrants and are classified in equity. The fair value of the warrants issued was approximately $1.8 million (see valuation assumptions in Note 4). The fair value of the inducement warrants of $1.8 million was expensed as warrant inducement expense in the accompanying consolidated statements of operations for the nine months ended September 30, 2019. On July 15, 2019, the Company entered into amendments (the “Amendments”) to the Exercise Agreements. Pursuant to the Amendments, the period during which the Exercising Holders may elect to exercise for cash the Existing Warrants in exchange for new warrants to purchase common stock to be issued in an amount equal to 75% of the number of shares of common stock exercised under the Existing Warrants was extended from July 15, 2019 to July 31, 2019. There were no additional warrants exercised under the Amendments during the second or third quarter of 2019.

Fair Value Measurement

Fair Value Measurement	9 Months Ended
	Sep. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurement	4. Fair Value Measurement The estimated nonrecurring fair value measurements associated with fixed asset purchases recorded as right-of-use asset finance lease obligations totaling approximately $583,000 during the nine months ended September 30, 2019 were calculated as the present value of the lease payments based on contractual payment amounts and estimated market rates. Upon adoption of guidance in ASC Topic 842 Leases, the estimated fair value of the right-of-use operating lease asset was recorded based on the present value of future lease payments based on contractual payment amounts and estimated market rates in effect. Other Fair Value Measurements As of the closing of the Company’s January 30, 2018 offering, the grant date fair value of the warrants issued to purchase up to 1,095,153 shares of common stock were estimated to be approximately $8.82 per share, or a total of approximately $9.7 million, was recorded as an offset to additional paid-in-capital on a relative fair value basis. The warrants sold in this offering currently have an exercise price of $1.20 per share, which is subject to down round adjustment, and expire five years from the date of issuance. The fair value of the warrants was estimated using a Monte Carlo simulation valuation model using Geometric Brownian Motion, incorporating anticipated future financing events, with the following assumptions: Beginning stock price $ 10.17 Exercise price $ 15.00 Expected dividend yield 0.00 % Discount rate-bond equivalent yield 2.48 % Expected life (in years) 5.00 Expected volatility 99.00 % As of the closing of the Company’s August 13, 2018 rights offering, the grant date fair value of the warrants issued to purchase up to 2,549,140 shares of common stock were estimated to be approximately $3.30 per share, or a total of approximately $8.4 million, was recorded as an offset to additional paid-in-capital on a relative fair value basis. The warrants sold in this offering have an exercise price of $4.53 per share and expire five years from the date of issuance. The fair value of the warrants was estimated using a Black-Scholes model, incorporating the following assumptions: Beginning stock price $ 3.89 Exercise price $ 4.53 Expected dividend yield 0.00 % Discount rate-bond equivalent yield 2.75 % Expected life (in years) 5.00 Expected volatility 128.69 % As of the closing of the Company’s September 20, 2018 offering, the grant date fair value of the warrants issued to purchase up to 762,438 shares of common stock were estimated to be approximately $2.57 per share, or a total of approximately $2.0 million, was recorded as an offset to additional paid-in-capital on a relative fair value basis. The warrants sold in this offering have an exercise price of $3.16 per share and expire five years from the initial exercise date, which is the six month anniversary of the date of issuance. The fair value of the warrants was estimated using a Black-Scholes model, incorporating the following assumptions: Beginning stock price $ 2.92 Exercise price $ 3.16 Expected dividend yield 0.00 % Discount rate-bond equivalent yield 2.77 % Expected life (in years) 5.50 Expected volatility 130.7 % Also, included in the September 20, 2018 offering the Company issued 120,000 pre-funded warrants. The pre-funded warrants had an intrinsic value of $350,000, were subsequently fully exercised and are no longer outstanding as of September 30, 2019. As of the closing of the Company’s February 12, 2019 offering, the estimated grant date fair value of approximately $0.95 per share associated with the warrants to purchase up to 7,165,000 shares of common stock issued in this offering, or a total of approximately $6.8 million, was recorded as an offset to additional paid-in capital on a relative fair value basis. All warrants sold in this offering have an exercise price of $1.20 per share, are exercisable immediately and expire five years from the date of issuance. The fair value of the warrants was estimated using a Black-Scholes model with the following assumptions: Beginning stock price $ 1.05 Exercise price $ 1.20 Expected dividend yield 0.00 % Discount rate-bond equivalent yield 2.49 % Expected life (in years) 5.00 Expected volatility 147.7 % As of the closing of the Company’s March 19, 2019 offering, the estimated grant date fair value of approximately $1.01 per share associated with the warrants to purchase up to 5,950,000 shares of common stock issued in this offering, or a total of approximately $6.0 million, was recorded as an offset to additional paid-in capital on a relative fair value basis. All warrants sold in this offering have an exercise price of $1.25 per share, are exercisable immediately and expire 5.5 years from the date of issuance. The fair value of the warrants was estimated using a Black-Scholes model with the following assumptions: Beginning stock price $ 1.12 Exercise price $ 1.25 Expected dividend yield 0.00 % Discount rate-bond equivalent yield 2.44 % Expected life (in years) 5.50 Expected volatility 140.0 % As of the closing of the Company’s May 30, 2019 warrant inducement transaction, the estimated grant date fair value of approximately $1.18 per share associated with the warrants to purchase up to 1,547,226 shares of common stock issued in this offering, or a total of approximately $1.8 million, was recorded as a warrant inducement expense with an offset to additional paid-in capital. All warrants issued in this warrant inducement transaction have an exercise price of $1.31 per share, are exercisable immediately and expire 5.5 years from the date of issuance. The fair value of the warrants was estimated using a Black-Scholes model with the following assumptions: Beginning stock price $ 1.29 Exercise price $ 1.31 Expected dividend yield 0.00 % Discount rate-bond equivalent yield 2.05 % Expected life (in years) 5.50 Expected volatility 145.9 %

Balance Sheet Details

Balance Sheet Details	9 Months Ended
	Sep. 30, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Balance Sheet Details	5. Balance Sheet Details The following provides certain balance sheet details: December 31, September 30, 2018 2019 Fixed Assets Machinery and equipment $ 2,818,583 $ 2,845,053 Furniture and office equipment 157,391 156,987 Computer equipment and software 1,437,408 1,552,981 Leasehold improvements 570,173 570,174 Financed equipment 2,573,955 — Construction in process 116,640 325,550 Total fixed assets, gross 7,674,150 5,450,745 Less accumulated depreciation and amortization (4,934,728 ) (4,125,490 ) Total fixed assets, net $ 2,739,422 $ 1,325,255 Accrued Liabilities Accrued payroll 255,426 458,750 Accrued vacation 535,682 566,811 Accrued bonuses 712,574 636,167 Accrued sales commissions 62,767 81,101 Current portion of deferred rent 158,342 — Accrued other 203,602 104,155 Total accrued liabilities $ 1,928,393 $ 1,846,984 During the nine months ended September 30, 2019 there were no disposals and $350,000 of fixed assets were acquired. Upon adoption of the lease guidance in ASC Topic 842, Leases (ASC 842), equipment with a total cost of $2,574,000 and accumulated depreciation of $1,135,000 were reclassified to right-of-use lease assets on the Company’s balance sheet (see Note 7). Depreciation expense for the nine months ended September 30, 2018 and 2019 was $580,366 and $691,191, respectively. Depreciation expense for the three months ended September 30, 2018 and 2019 was $223,194 and $240,207, respectively.

April 2014 Credit Facility

April 2014 Credit Facility	9 Months Ended
	Sep. 30, 2019
Debt Disclosure [Abstract]
April 2014 Credit Facility	6. April 2014 Credit Facility On April 30, 2014, the Company received net cash proceeds of approximately $4,898,000 pursuant to the execution of the April 2014 Credit Facility. Upon entering into the April 2014 Credit Facility, the Company was required to pay the lender a facility fee of $50,000 in conjunction with the funding of the term loan. The April 2014 Credit Facility was secured by substantially all of the Company’s personal property other than its intellectual property. The term loan under the April 2014 Credit Facility bore interest at an annual rate of 7.95%. The Company was required to make interest-only payments on the term loan through August 1, 2015. The outstanding term loan under the April 2014 Credit Facility began amortizing at the end of the applicable interest-only period, with monthly payments of principal and interest being made by the Company to the lender in consecutive monthly installments following such interest-only period. The term loan under the April 2014 Credit Facility matured on July 1, 2018. Under the original terms of the underlying agreement, the Company was also required to make a final payment to the lender equal to 5.5% of the original principal amount of the term loan funded. Upon maturity of the April 2014 Credit Facility on July 1, 2018, security interest in the Company’s personal property was released by the lender. A warrant to purchase up to 588 shares of the Company’s common stock at an exercise price of $424.80 per share with a term of 10 years was issued to Oxford Finance LLC on April 30, 2014. Issuance costs of approximately $102,000 associated with the term loan under the April 2014 Credit Facility were recorded as a discount to outstanding debt as of the closing date, resulting in net proceeds of approximately $4,898,000. The estimated fair value of the warrant issued of approximately $233,000 was also recorded as a discount to outstanding debt as of the closing date. The discounts and other issuance costs were amortized to interest expense utilizing the effective interest method over the underlying term of the loan.

Leases

Leases	9 Months Ended
	Sep. 30, 2019
Leases [Abstract]
Leases	7. Leases Effective January 1, 2019, the Company adopted US GAAP accounting rules in ASC Topic 842, Leases (ASC 842), using the modified retrospective method. The Company elected to follow the package of practical expedients provided under the transition guidance within ASC 842, and accordingly, did not reassess whether any expired or existing contracts are or contain leases, did not reassess expired or existing leases, and did not reassess initial direct costs for any existing leases. Upon adoption, the Company recorded an operating lease right-of-use asset and an operating lease liability on the balance sheet. In addition, assets under equipment leases previously classified as capital leases within Property, Plant and Equipment on the Company’s balance sheet were reclassified to finance lease right-of-use assets upon adoption of the guidance. Right-of-use assets and obligations were recognized based on the present value of remaining lease payments over the lease term. As the Company’s operating lease does not provide an implicit rate, an estimated incremental borrowing rate was used based on the information available at the adoption date in determining the present value of lease payments. Operating lease expense is recognized on a straight-line basis over the lease term. Variable lease costs such as common area costs and other operating costs are expensed as incurred. Leases with an initial term of 12 months or less are not recorded on the balance sheet. Finance Leases The Company leases certain laboratory equipment under arrangements previously accounted for as capital leases, classified on the Company’s balance sheet as fixed assets and related lease liabilities and depreciated on a straight line basis over the lease term. Upon adoption of ASC 842, leased equipment previously classified as fixed assets totaling $1.4 million in net book value were reclassified to lease right-of-use assets in accordance with the guidance. The equipment under finance leases is depreciated on a straight-line basis over periods ranging from approximately 3 to 7 years. The total gross value of equipment capitalized under such lease arrangements was approximately $2,574,000 and $3,075,000 at December 31, 2018 and September 30, 2019, respectively. Total accumulated depreciation related to equipment under finance leases was approximately $1,135,000 and $1,500,000 at December 31, 2018 and September 30, 2019, respectively. Total depreciation expense related to equipment under finance leases during the three months ended September 30, 2018 and 2019 was approximately $115,000 and $134,000, and during the nine months ended September 30, 2018 and 2019 was approximately $271,000 and $365,000, respectively. On January 31, 2019, the Company executed an equipment financing commitment with a third-party lender for total amount of approximately $149,000, which was funded by the lender on February 1, 2019. Under the terms of the equipment financing agreement, which was accounted for as a finance lease transaction, the principal balance plus interest for the equipment are to be repaid in full after 36 monthly installments of $5,013 totaling approximately $180,000 through February 2022. In July 2019, an equipment financing commitment was executed with a third-party lender for total amount of approximately $100,000, which was accounted for as a finance lease transaction with the principal balance plus interest for the equipment to be repaid in full after 48 monthly installments of $2,706 totaling approximately $130,000 through May 2023. In August 2019, an equipment financing commitment was executed with a third-party lender for total amount of approximately $245,000, which was accounted for as a finance lease transaction with the principal balance plus interest for the equipment to be repaid in full after 36 monthly installments of $8,253 totaling approximately $297,000 through August 2022. In September 2019, an additional equipment financing commitment was executed with a third-party lender for total additional amount of approximately $89,000, which was accounted for as a finance lease transaction with the principal balance plus interest for the equipment to be repaid in full after 60 monthly installments of $1,770 totaling approximately $106,000 through September 2024. Operating Lease The Company leases its primary laboratory and office facilities in San Diego, California. This lease is classified as an operating lease in accordance with the ASC 842 guidance. The average monthly cash payment for the operating lease is approximately $120,000 per month, and the lease term ends on July 31, 2020. The Company recorded a lease right-of-use asset and lease liability of $1,930,000 and $2,201,000, respectively, as of January 1, 2019, based on present value of payments and an incremental borrowing rate of 4.5%. In addition, the Company reviews agreements at inception to determine if they include a lease, and when they do, uses its incremental borrowing rate or implicit interest rate to determine the present value of the future lease payments. The following schedule sets forth the components of right-of-use lease assets as of December 31, 2018 and September 30, 2019 as follows: December 31, September 30, 2018 2019 Lease right-of-use assets: Operating $ — $ 1,035,210 Finance — 1,575,039 Total $ — $ 2,610,249 The following schedule sets forth the current portion of operating and finance lease liabilities as of December 31, 2018 and September 30, 2019: December 31, September 30, 2018 2019 Current portion of lease liability: Operating $ — 1,193,255 Finance — 776,030 Total $ — $ 1,969,285 The following schedule sets forth the long-term portion of operating and finance lease liabilities as of December 31, 2018 and September 30, 2019: December 31, September 30, 2018 2019 Long-term portion of lease liability: Operating $ — $ — Finance — 1,032,243 Total $ — $ 1,032,243 The following schedule represents the components of lease expense for the three and nine months ended September 30, 2018 and 2019: For the three months ended September 30, For the nine months ended September 30, 2018 2019 2018 2019 Lease cost Finance lease cost Amortization of right-of-use assets $ — $ 134,472 $ — $ 364,401 Interest on lease liabilities — 62,026 — 187,574 Operating lease cost — 318,005 — 954,015 Total $ — $ 514,503 $ — $ 1,505,990 The following schedule sets forth the remaining future minimum lease payments outstanding under finance and operating leases, as well as corresponding remaining sales tax and maintenance obligation payments that are expensed as incurred and due within each respective year ending December 31, as well as the present value of the total amount of the remaining minimum lease payments, as of September 30, 2019: Finance Operating Minimum Maintenance and Minimum Lease Sales Tax Obligation Lease Payments Payments Payments 2019 (remaining) $ 222,245 $ 27,016 $ 362,929 2020 764,533 89,136 855,136 2021 517,927 67,974 — 2022 405,318 57,260 — 2023 263,274 56,799 — Thereafter 58,448 8,241 — Total payments 2,231,745 306,426 1,218,065 Less amount representing interest (423,472 ) — (24,810 ) Present value of payments $ 1,808,273 $ 306,426 $ 1,193,255 The following schedule sets forth supplemental cash flow information related to operating and finance leases as of September 30, 2019: For the three months ended For the nine months ended September 30, 2019 September 30, 2019 Other information Operating cash flows from financing leases $ 62,026 $ 187,574 Operating cash flows from operating leases $ 355,813 $ 1,067,437 Financing cash flows from finance leases $ 101,139 $ 378,389 The aggregate weighted average remaining lease term was 3.14 years on finance leases and 0.84 years on operating leases as of September 30, 2019. The aggregate weighted average discount rate was 20.30% on finance leases and 4.5% on operating leases as of September 30, 2019. During the nine months ended September 30, 2019, the Company added $583,000 of right of use assets in exchange for finance lease liabilities. In addition, upon adoption of the accounting guidance in ASC 842, $1.4 million of net machinery and equipment was reclassified to lease right-of-use assets related to assets under finance leases and $1.9 million of right-of-use facility lease was recorded under operating lease.

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	8. Stock-Based Compensation Equity Incentive Plans The Company maintains two equity incentive plans: The Amended and Restated 2013 Equity Incentive Plan, or the 2013 Plan, and the 2007 Equity Incentive Plan, or the 2007 Plan. The 2013 Plan includes a provision that shares available for grant under the Company’s 2007 Plan become available for issuance under the 2013 Plan and are no longer available for issuance under the 2007 Plan. At the Company’s annual meeting of stockholders held on June 28, 2018, the Company’s stockholders approved amendments to the 2013 Plan, which included an increase in the number of non-inducement shares of common stock authorized for issuance under the 2013 Plan by 146,666 shares. At the Company’s annual meeting of stockholders held on June 17, 2019, the Company’s stockholders approved additional amendments to the 2013 Plan including the increase in the number of non-inducement shares of common stock authorized for issuance under the 2013 Plan by 2,800,000 shares. As of September 30, 2019, 124,211 shares of the Company’s common stock were authorized exclusively for the issuance of stock awards to employees who have not previously been an employee or director of the Company, except following a bona fide period of non-employment, as an inducement material to the individual’s entering into employment with the Company, as defined under applicable Nasdaq Listing Rules. As of September 30, 2019, under all plans, a total of 3,064,098 non-inducement shares were authorized for issuance, 2,711,095 shares had been issued with 2,650,970 non-inducement stock options and restricted stock units, or RSUs, underlying outstanding awards, and 353,003 non-inducement shares were available for grant. As of September 30, 2019, 118,368 inducement shares were authorized for issuance, 118,368 inducement shares had been issued under the 2013 Plan, with 117,534 inducement stock options and RSUs underlying outstanding awards and no inducement shares available for grant. Stock Options A summary of stock option activity for the nine months ended September 30, 2019 is as follows: Weighted Average Weighted Remaining Number of Average Exercise Contractual Shares Price Per Share Term in Years Outstanding at December 31, 2018 195,820 $ 41.41 9.20 Granted 2,664,129 $ 0.91 Exercised — — Cancelled/forfeited/expired (62,293 ) $ 6.43 Outstanding at September 30, 2019 2,797,656 $ 3.62 9.52 Vested and unvested expected to vest at September 30, 2019 2,701,017 $ 3.71 9.52 The intrinsic values of options outstanding, options exercisable, and options vested and unvested expected to vest at December 31, 2018 and September 30, 2019 were each approximately zero. The assumptions used in the Black-Scholes pricing model for stock options granted during the three and nine months ended September 30, 2019 were as follows: Stock and exercise prices $0.81 - $1.03 Expected dividend yield 0.00% Discount rate-bond equivalent yield 1.58% – 2.55% Expected life (in years) 5.00 – 5.96 Expected volatility 128% - 156% On April 30, 2019, the Company’s Board of Directors approved the issuance of an aggregate of 2,578,229 options to be granted to the Company’s employees, executives and Board members pursuant to the 2013 Amended Plan, subject to shareholder approval of the increase of the options available under the 2013 Amended Plan at the Company’s annual meeting on June 17, 2019. On June 17, 2019 the Company’s shareholders approved the increase to the 2013 Amended Plan by 2.8 million shares. Restricted Stock A summary of RSU activity for the nine months ended September 30, 2019 is as follows: Weighted Number of Average Grant Shares Date Fair Value Outstanding at December 31, 2018 360 $ 415.80 Granted — — Vested and issued — — Forfeited — — Outstanding at September 30, 2019 360 $ 415.80 Vested and unvested expected to vest at September 30, 2019 360 $ 415.80 At September 30, 2019, the intrinsic values of RSUs outstanding and RSUs unvested and expected to vest were each approximately $400. Of the 360 RSUs outstanding at September 30, 2019, all were fully vested. Stock-based Compensation Expense The following table presents the effects of stock-based compensation related to equity awards to employees and nonemployees on the unaudited condensed statements of operations and comprehensive loss during the periods presented: For the three months ended For the nine months ended September 30, September 30, 2018 2019 2018 2019 Stock Options Cost of revenues $ 10,150 $ 29,405 $ 37,150 $ 54,625 Research and development expenses 30,247 37,626 103,267 102,742 General and administrative expenses 57,162 168,484 243,593 361,102 Sales and marketing expenses 15,513 62,154 63,594 106,300 Total expenses related to stock options 113,072 297,669 447,604 624,769 RSUs Cost of revenues - - (18,802 ) - Research and development expenses - - 13,576 - General and administrative expenses - - 54,303 - Sales and marketing expenses - - 15,348 - Total stock-based compensation $ 113,072 $ 297,669 $ 512,029 $ 624,769 Stock-based compensation expense was recorded net of estimated forfeitures of 0% - 8% per annum during each of the three and nine months ended September 30, 2018 and 2019. As of September 30, 2019, total unrecognized share-based compensation expense related to unvested stock options and RSUs, adjusted for estimated forfeitures, was approximately $2,545,000 and is expected to be recognized over a weighted-average period of approximately 3.2 years.

Common Stock Warrants Outstandi

Common Stock Warrants Outstanding	9 Months Ended
	Sep. 30, 2019
Other Liabilities Disclosure [Abstract]
Common Stock Warrants Outstanding	9. Common Stock Warrants Outstanding A summary of equity-classified common stock warrant activity for the nine months ended September 30, 2019 is as follows: Average Weighted Remaining Number of Average Exercise Contractual Shares Price Per Share Term in Years Outstanding at December 31, 2018 4,694,927 $ 8.55 4.4 Issued 14,662,226 $ 1.23 Exercised (4,155,430 ) 1.20 Expired (4,474 ) 953.06 Outstanding at September 30, 2019 15,197,249 $ 3.08 4.5 Further information about equity-classified common stock warrants outstanding at September 30, 2019 is as follows: Weighted Weighted Average Average Total Shares Contractual Exercise Price Outstanding Life (in years) $ 1.24 11,601,949 4.7 $ 4.21 3,311,578 3.9 $ 25.50 8,208 3.2 $ 33.00 96,999 2.1 $ 45.00 47,821 2.9 $ 75.00 71,995 3.0 $ 117.00 38,772 1.6 $ 140.00 19,339 0.4 $ 424.80 588 4.6 15,197,249 All warrants outstanding at September 30, 2019 are exercisable. The intrinsic value of equity-classified common stock warrants outstanding at September 30, 2019 was zero.

Net Loss per Common Share

Net Loss per Common Share	9 Months Ended
	Sep. 30, 2019
Earnings Per Share [Abstract]
Net Loss per Common Share	10. Net Loss per Common Share Basic and diluted net loss per common share is determined by dividing net loss applicable to common shareholders by the weighted-average common shares outstanding during the period. Because there is a net loss attributable to common shareholders for the three and nine months ended September 30, 2018 and 2019, the outstanding RSUs, warrants, and common stock options have been excluded from the calculation of diluted loss per common share because their effect would be anti-dilutive. Based on applicable guidance, the 120,000 pre-funded warrants that were issued in the September 20, 2018 registered direct offering with an exercise price of $0.01 are considered common stock equivalents and are included in the calculation of basic and diluted loss per share. In other periods presented, the weighted-average shares used to calculate both basic and diluted loss per share are the same. The following potentially dilutive securities have been excluded from the computations of diluted weighted-average shares outstanding for the periods presented, as they would be anti-dilutive: For the three and nine months ended September 30, 2018 2019 Preferred warrants outstanding (number of common stock equivalents) 17 — Common warrants outstanding 4,814,927 15,197,249 RSUs outstanding 360 360 Convertible preferred stock outstanding (number of common stock equivalents) 2,560,727 471,393 Common options outstanding 114,641 2,797,656 Total anti-dilutive common share equivalents 7,490,672 18,466,658

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2019
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	11. Commitments and Contingencies In the normal course of business, the Company may be involved in legal proceedings or threatened legal proceedings. The Company is not party to any legal proceedings or aware of any threatened legal proceedings that are expected to have a material adverse effect on its financial condition, results of operations or liquidity. In February 2016, the Company signed a firm, non-cancelable, and unconditional commitment in an aggregate amount of $1,062,500 with a vendor to purchase certain inventory items, payable in minimum quarterly amounts of $62,500 through May 2020. At September 30, 2019, a balance of approximately $154,000 remained outstanding under this purchase commitment. During the three months ended September 30, 2018 and 2019, total expense recorded in the Company’s unaudited condensed statements of operations and comprehensive loss for sales tax and maintenance obligations associated with equipment financing arrangements was approximately $25,000 and $35,000, respectively, with approximately $75,000 and $82,000 recorded during the nine months ended September 30, 2018 and 2019, respectively. At December 31, 2018 and September 30, 2019, approximately $69,000 and $71,000, respectively, of such sales tax and maintenance obligations incurred but not paid were recorded in accrued other liabilities in the Company’s balance sheet (see Note 5). Future amounts totaling approximately $306,426 for sales tax and maintenance obligations associated with financed equipment were due under equipment financing arrangements at September 30, 2019, which will be expensed as incurred (see Note 7).

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2019
Related Party Transactions [Abstract]
Related Party Transactions	12. Related Party Transactions A member of the Company’s management is the controlling person of Aegea Biotechnologies, Inc., or Aegea. On September 2, 2012, the Company entered into an Assignment and Exclusive Cross-License Agreement, or the Cross-License Agreement, with Aegea. The Company received no payments from during the three months ended September 30, 2018 and 2019, and approximately $19,000 and $26,000 was received during the nine months ended September 30, 2018 and 2019, respectively, from Aegea as reimbursements for shared patent costs under the Cross-License Agreement.

The Company, Business Activit_2

The Company, Business Activities and Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
The Company and Business Activities	The Company and Business Activities The Company was founded in California in May 1997 and effected a reincorporation to Delaware in July 2013. The Company is an early stage molecular oncology diagnostics company that develops and commercializes proprietary circulating tumor cell, or CTC, and circulating tumor DNA, or ctDNA, assays utilizing a standard blood sample, or liquid biopsy. The Company’s current and planned assays are intended to provide information to aid healthcare providers to identify specific oncogenic alterations that may qualify a subset of cancer patients for targeted therapy at diagnosis, progression or for monitoring in order to identify specific resistance mechanisms. Sometimes traditional procedures, such as surgical tissue biopsies, result in tumor tissue that is insufficient and/or unable to provide the molecular subtype information necessary for clinical decisions. The Company’s assays, performed on blood, have the potential to provide more contemporaneous information on the characteristics of a patient’s disease when compared with tissue biopsy and radiographic imaging. Additionally, commencing in October 2017, the Company’s pathology partnership program, branded as Empower TC TM The Company operates a clinical laboratory that is CLIA-certified (under the Clinical Laboratory Improvement Amendment of 1988) and CAP-accredited (by the College of American Pathologists), and manufactures cell enrichment and extraction microfluidic channels, related equipment and certain reagents to perform the Company’s diagnostic assays in a facility located in San Diego, California. CLIA certification and accreditation are required before any clinical laboratory may perform testing on human specimens for the purpose of obtaining information for the diagnosis, prevention, treatment of disease, or assessment of health. The assays the Company offers are classified as laboratory developed tests under the CLIA regulations.
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed financial statements and notes are prepared in accordance with accounting principles generally accepted in the United States of America, or GAAP, and on the basis that the Company will continue as a going concern (see Note 2). The accompanying unaudited condensed financial statements and notes do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classification of liabilities that may result from the possible inability of the Company to continue as a going concern. On July 6, 2018, the Company’s stockholders approved, and the Company filed, an amendment to the Company’s Certificate of Amendment of Certificate of Incorporation to effect a one-for-thirty reverse stock split of the Company’s outstanding common stock. As such, all references to share and per share amounts in these unaudited condensed financial statements and accompanying notes have been retroactively restated to reflect the one-for-thirty reverse stock split, except for the authorized number of shares of the Company’s common stock of 150,000,000 The unaudited condensed financial statements included in this Form 10-Q have been prepared in accordance with the U.S. Securities and Exchange Commission, or SEC, instructions for Quarterly Reports on Form 10-Q. Accordingly, the condensed financial statements are unaudited and do not contain all the information required by GAAP to be included in a full set of financial statements. The balance sheet at December 31, 2018 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by GAAP for a complete set of financial statements. The audited financial statements for the year ended December 31, 2018, filed with the U.S. Securities and Exchange Commission, or SEC, with our Annual Report on Form 10-K on March 29, 2019 include a summary of our significant accounting policies and should be read in conjunction with this Form 10-Q. In the opinion of management, all material adjustments necessary to present fairly the results of operations for such periods have been included in this Form 10-Q. All such adjustments are of a normal recurring nature. The results of operations for interim periods are not necessarily indicative of the results of operations for the entire year. Certain prior period balances have been reclassified to conform to the current period presentation. Such reclassifications had no effect on net loss.
Revenue Recognition and Accounts Receivable	Revenue Recognition and Accounts Receivable The Company's commercial revenues are generated from diagnostic services provided to patient’s physicians and billed to third-party insurance payers such as managed care organizations, Medicare and Medicaid and patients for any deductibles, coinsurance or copayments that may be due. Commencing on January 1, 2018, the Company recognizes revenue in accordance with ASC 606, Revenue from Contracts with Customers, or ASC 606, which requires that an entity recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled to in exchange for those goods or services. The Company adopted the provisions of ASC 606 using the modified retrospective application method applied to all contracts, which did not impact amounts previously reported by the Company, nor did it require a cumulative effect adjustment upon adoption, as the Company’s method of recognizing revenue under ASC 606 was analogous to the method utilized immediately prior to adoption. Accordingly, there is no need for the Company to disclose the amount by which each financial statement line item was affected as a result of applying the new standard and an explanation of significant changes. Contracts For its commercial revenues, while the Company markets directly to physicians, its customer is the patient. Patients do not enter into direct agreements with the Company, however, a patient’s insurance coverage requirements would dictate whether or not any portion of the cost of the tests would be patient responsibility. Accordingly, the Company establishes contracts with commercial insurers in accordance with customary business practices, as follows: • Approval of a contract is established via the order and accession, which are submitted by the patient’s physician. • The Company is obligated to perform its diagnostic services upon receipt of a sample from a physician, and the patient and/or applicable payer are obligated to reimburse the Company for services rendered based on the patient’s insurance benefits. • Payment terms are a function of a patient’s existing insurance benefits, including the impact of coverage decisions with CMS and applicable reimbursement contracts established between the Company and payers, unless the patient is a self-pay patient, whereby the Company bills the patient directly after the services are provided. • On ce the Company delivers a patient’s assay result to the ordering physician, the contract with a patient has commercial substance, as the Company is legally able to collect payment and bill an insurer and/or patient, regardless of payer contract status or patient insurance benefit status. • Consideration associated with commercial revenues is considered variable and constrained until fully adjudicated, with net revenues recorded to the extent that it is probable that a significant reversal will not occur. The Company’s development services revenues are supported by contractual agreements and generated from assay development services provided to entities, as well as certain other diagnostic services provided to physicians, and revenues are recognized upon delivery of the performance obligations in the contract. Performance Obligations A performance obligation is a promise in a contract to transfer a distinct good or service, or a bundle of goods or services, to the customer. For its commercial and development services revenues, the Company’s contracts have a single performance obligation, which is satisfied upon rendering of services, which culminates in the delivery of a patient’s assay result(s) to the ordering physician or entity. The duration of time between accession receipt and delivery of a valid assay result to the ordering physician or entity is typically less than two weeks. Accordingly, the Company elected the practical expedient and therefore, does not disclose the value of unsatisfied performance obligations. Transaction Price The transaction price is the amount of consideration that the Company expects to collect in exchange for transferring promised goods or services to a customer, excluding amounts collected on behalf of third parties, such as sales taxes. The consideration expected from a contract with a customer may include fixed amounts, variable amounts, or both. The Company’s gross commercial revenues billed, and corresponding gross accounts receivable, are subject to estimated deductions for such allowances and reserves to arrive at reported net revenues, which relate to differences between amounts billed and corresponding amounts estimated to be subsequently collected, and is deemed to be variable although the variability is not explicitly stated in any contract. Rather, the implied variability is due to several factors, such as the payment history or lack thereof for third-party payers, reimbursement rate changes for contracted and non-contracted payers, any patient co-payments, deductibles or compliance incentives, the existence of secondary payers and claim denials. The Company estimates the The Company limits the amount of variable consideration included in the transaction price to the unconstrained portion of such consideration. Revenue is recognized up to the amount of variable consideration that is not subject to a significant reversal until additional information is obtained or the uncertainty associated with the additional payments or refunds is subsequently resolved. Differences between original estimates and subsequent revisions, including final settlements, represent changes in the estimate of variable consideration and are included in the period in which such revisions are made. The Company monitors its estimates of transaction price to depict conditions that exist at each reporting date. If the Company subsequently determines that it will collect more consideration than it originally estimated for a contract with a customer, it will account for the change as an increase in the estimate of the transaction price in the period identified as an increase to revenue. Similarly, if the Company subsequently determines that the amount it expects to collect from a customer is less than it originally estimated, it will generally account for the change as a decrease in the estimate of the transaction price as a decrease to revenue, provided that such downward adjustment does not result in a significant reversal of cumulative revenue recognized. Revenue recognized from changes in transaction prices was not significant during the three and nine months ended September 30, 2018 and 2019. Allocate Transaction Price For the Company’s commercial revenues, the entire transaction price is allocated to the single performance obligation contained in a contract with a customer. For the Company’s development services revenues, the contracted transaction price is allocated to each single performance obligation contained in a contract with a customer as performed. Point-in-time Recognition The Company’s single performance obligation is satisfied at a point in time, and that point in time is defined as the date a patient’s successful assay result is delivered to the patient’s ordering physician or entity. The Company considers this date to be the time at which the patient obtains control of the promised diagnostic assay service. Contract Balances The timing of revenue recognition, billings and cash collections results in accounts receivable recorded in the Company’s condensed balance sheets. Generally, billing occurs subsequent to delivery of a patient’s test result to the ordering physician or entity, resulting in an account receivable. Practical Expedients The Company does not adjust the transaction price for the effects of a significant financing component, as at contract inception, the Company expects the collection cycle to be one year or less. The Company expenses sales commissions when incurred because the amortization period is one year or less, which are recorded within sales and marketing expenses. The Company incurs certain other costs that are incurred regardless of whether a contract is obtained. Such costs are primarily related to legal services and patient communications. These costs are expensed as incurred and recorded within general and administrative expenses. Disaggregation of Revenue and Concentration of Risk The composition of the Company’s net revenues recognized during the three and nine months ended September 30, 2018 and 2019, disaggregated by source and nature, are as follows: For the three months ended September 30, For the nine months ended September 30, 2018 2019 2018 2019 Net revenues from contracted payers* $ 325,097 $ 476,101 $ 1,019,857 $ 1,447,421 Net revenues from non-contracted payers 373,018 956,140 1,201,869 2,080,018 Development services revenues 63,476 37,981 159,606 125,169 Kits and Blood Collection Tubes (BCT) — 59,040 9,440 92,216 Total net revenues $ 761,591 $ 1,529,262 $ 2,390,772 $ 3,744,824 *Includes Medicare and Medicare Advantage, as reimbursement amounts are fixed. For the three months ended September 30, For the nine months ended September 30, 2018 2019 2018 2019 Net commercial revenues recognized upon delivery $ 698,115 $ 1,432,241 $ 2,221,726 $ 3,527,439 Development services revenues recognized upon delivery 63,476 37,981 159,606 125,169 Kits and Blood Collection Tubes (BCT) — 59,040 9,440 92,216 Total net revenues $ 761,591 $ 1,529,262 $ 2,390,772 $ 3,744,824 Concentrations of credit risk with respect to revenues are primarily limited to geographies to which the Company provides a significant volume of its services, and to specific third-party payers of the Company’s services such as Medicare, insurance companies, and other third-party payers. The Company’s client base consists of many geographically dispersed clients diversified across various customer types. The Company's third-party payers that represent more than 10% of total net revenues in any period presented, as well as their related net revenue amount as a percentage of total net revenues, during the three and nine months ended September 30, 2018 and 2019 were as follows: For the three months ended September 30, For the nine months ended September 30, 2018 2019 2018 2019 Medicare and Medicare Advantage 40 % 32 % 39 % 40 % Blue Cross Blue Shield 9 % 25 % 14 % 20 % United Healthcare 6 % 8 % 15 % 9 % The Company's third-party payers that represent more than 10% of total net accounts receivable, and their related net accounts receivable balance as a percentage of total net accounts receivable, at December 31, 2018 and September 30, 2019 were as follows: December 31, 2018 September 30, 2019 Blue Cross Blue Shield 22 % 25 % Medicare and Medicare Advantage 17 % 17 % United Healthcare 15 % 13 %
Recent Accounting Pronouncements	Recent Accounting Pronouncements In February 2016, the FASB issued authoritative guidance, which changes several aspects of the accounting for leases, including the requirement that all leases with durations greater than twelve months be recognized on the balance sheet. The guidance is effective for annual and interim reporting periods in fiscal years beginning after December 15, 2018. Effective January 1, 2019, the Company adopted the guidance and elected the optional transition method to account for the impact of the adoption with a cumulative-effect adjustment in the period of adoption and did not restate prior periods. The Company also elected the practical expedient package as permitted under the transition guidance. As of January 1, 2019, the Company recorded a right-of-use asset and liability upon adoption of the guidance (See Note 7). In August 2017, the FASB issued authoritative guidance that expands and refines hedge accounting for both nonfinancial and financial risk components and align the recognition and presentation of the effects of the hedging instrument and the hedged item in the financial statements. This guidance is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early application is permitted. The Company adopted this guidance for the fiscal year beginning on January 1, 2019 and determined that the adoption of this guidance does not have a material impact on its financial statements or disclosures because the Company does not currently hold any financial instruments accounted for as a hedging activity. In February 2018, the FASB issued authoritative guidance allowing a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from a tax bill, “H.R.1, An Act to Provide for Reconciliation Pursuant to Titles II and V of the Concurrent Resolution on the Budget for Fiscal Year 2018,” or the Tax Cuts and Jobs Act, enacted on December 22, 2017. These amendments eliminate the stranded tax effects resulting from the Tax Cuts and Jobs Act. However, because these amendments only relate to the reclassification of the income tax effects of the Tax Cuts and Jobs Act, the underlying guidance that requires that the effect of a change in tax laws or rates be included in income from continuing operations is not affected. This guidance also requires certain disclosures about stranded tax effects. This guidance is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption is permitted. The Company adopted this guidance for the fiscal year beginning on January 1, 2019 which did not have a material impact on its financial statements or disclosures because the Company does not currently maintain any stranded tax effects in accumulated other comprehensive income. In June 2018, the FASB issued authoritative guidance simplifying the accounting for nonemployee stock-based compensation and largely aligning such compensation with the accounting requirements for employee stock-based awards. For public companies, this guidance is effective for fiscal years beginning after December 15, 2018, including interim periods within that fiscal year. The Company adopted this guidance for the fiscal year beginning on January 1, 2019 and determined that the adoption of this guidance does not have a material impact on its financial statements or disclosures. In November 2018, the FASB issued authoritative guidance clarifying the interaction between Collaborative Arrangements (Topic 808) and Revenue from Contracts with Customers (Topic 606) to address diversity in practice related to how companies account for collaborative arrangements. For public companies, this guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within that fiscal year. Early adoption is permitted, but no earlier than an entity’s adoption date of Revenue from Contracts with Customers (Topic 606). The Company currently intends to adopt this guidance upon the effective date and does not anticipate that the adoption of this guidance will have a material impact on its financial statements or disclosures.

The Company, Business Activit_3

The Company, Business Activities and Basis of Presentation (Tables)	9 Months Ended
	Sep. 30, 2019
Accounting Policies [Abstract]
Composition of Net Revenues Recognized Disaggregated by Source and Nature	The composition of the Company’s net revenues recognized during the three and nine months ended September 30, 2018 and 2019, disaggregated by source and nature, are as follows: For the three months ended September 30, For the nine months ended September 30, 2018 2019 2018 2019 Net revenues from contracted payers* $ 325,097 $ 476,101 $ 1,019,857 $ 1,447,421 Net revenues from non-contracted payers 373,018 956,140 1,201,869 2,080,018 Development services revenues 63,476 37,981 159,606 125,169 Kits and Blood Collection Tubes (BCT) — 59,040 9,440 92,216 Total net revenues $ 761,591 $ 1,529,262 $ 2,390,772 $ 3,744,824 *Includes Medicare and Medicare Advantage, as reimbursement amounts are fixed. For the three months ended September 30, For the nine months ended September 30, 2018 2019 2018 2019 Net commercial revenues recognized upon delivery $ 698,115 $ 1,432,241 $ 2,221,726 $ 3,527,439 Development services revenues recognized upon delivery 63,476 37,981 159,606 125,169 Kits and Blood Collection Tubes (BCT) — 59,040 9,440 92,216 Total net revenues $ 761,591 $ 1,529,262 $ 2,390,772 $ 3,744,824
Summary of Third-Party Payers That Represent More Than 10% of Total Net Revenues and Total Net Accounts Receivable and Their Related Percentage	The Company's third-party payers that represent more than 10% of total net revenues in any period presented, as well as their related net revenue amount as a percentage of total net revenues, during the three and nine months ended September 30, 2018 and 2019 were as follows: For the three months ended September 30, For the nine months ended September 30, 2018 2019 2018 2019 Medicare and Medicare Advantage 40 % 32 % 39 % 40 % Blue Cross Blue Shield 9 % 25 % 14 % 20 % United Healthcare 6 % 8 % 15 % 9 % The Company's third-party payers that represent more than 10% of total net accounts receivable, and their related net accounts receivable balance as a percentage of total net accounts receivable, at December 31, 2018 and September 30, 2019 were as follows: December 31, 2018 September 30, 2019 Blue Cross Blue Shield 22 % 25 % Medicare and Medicare Advantage 17 % 17 % United Healthcare 15 % 13 %

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	9 Months Ended
	Sep. 30, 2019
Fair Value Disclosures [Abstract]
Assumptions Used for Determining Fair Values of Common Stock Warrants	The fair value of the warrants was estimated using a Monte Carlo simulation valuation model using Geometric Brownian Motion, incorporating anticipated future financing events, with the following assumptions: Beginning stock price $ 10.17 Exercise price $ 15.00 Expected dividend yield 0.00 % Discount rate-bond equivalent yield 2.48 % Expected life (in years) 5.00 Expected volatility 99.00 % Beginning stock price $ 3.89 Exercise price $ 4.53 Expected dividend yield 0.00 % Discount rate-bond equivalent yield 2.75 % Expected life (in years) 5.00 Expected volatility 128.69 % Beginning stock price $ 2.92 Exercise price $ 3.16 Expected dividend yield 0.00 % Discount rate-bond equivalent yield 2.77 % Expected life (in years) 5.50 Expected volatility 130.7 % Beginning stock price $ 1.05 Exercise price $ 1.20 Expected dividend yield 0.00 % Discount rate-bond equivalent yield 2.49 % Expected life (in years) 5.00 Expected volatility 147.7 % Beginning stock price $ 1.12 Exercise price $ 1.25 Expected dividend yield 0.00 % Discount rate-bond equivalent yield 2.44 % Expected life (in years) 5.50 Expected volatility 140.0 % Beginning stock price $ 1.29 Exercise price $ 1.31 Expected dividend yield 0.00 % Discount rate-bond equivalent yield 2.05 % Expected life (in years) 5.50 Expected volatility 145.9 %

Balance Sheet Details (Tables)

Balance Sheet Details (Tables)	9 Months Ended
	Sep. 30, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Schedule of Fixed Assets and Accrued Liabilities	The following provides certain balance sheet details: December 31, September 30, 2018 2019 Fixed Assets Machinery and equipment $ 2,818,583 $ 2,845,053 Furniture and office equipment 157,391 156,987 Computer equipment and software 1,437,408 1,552,981 Leasehold improvements 570,173 570,174 Financed equipment 2,573,955 — Construction in process 116,640 325,550 Total fixed assets, gross 7,674,150 5,450,745 Less accumulated depreciation and amortization (4,934,728 ) (4,125,490 ) Total fixed assets, net $ 2,739,422 $ 1,325,255 Accrued Liabilities Accrued payroll 255,426 458,750 Accrued vacation 535,682 566,811 Accrued bonuses 712,574 636,167 Accrued sales commissions 62,767 81,101 Current portion of deferred rent 158,342 — Accrued other 203,602 104,155 Total accrued liabilities $ 1,928,393 $ 1,846,984

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2019
Leases [Abstract]
Schedule of Right-Of-Use Lease Assets	The following schedule sets forth the components of right-of-use lease assets as of December 31, 2018 and September 30, 2019 as follows: December 31, September 30, 2018 2019 Lease right-of-use assets: Operating $ — $ 1,035,210 Finance — 1,575,039 Total $ — $ 2,610,249
Schedule of Current Portion of Operating and Finance Lease Liabilities	The following schedule sets forth the current portion of operating and finance lease liabilities as of December 31, 2018 and September 30, 2019: December 31, September 30, 2018 2019 Current portion of lease liability: Operating $ — 1,193,255 Finance — 776,030 Total $ — $ 1,969,285
Schedule of Long-Term Portion of Operating and Finance Lease Liabilities	The following schedule sets forth the long-term portion of operating and finance lease liabilities as of December 31, 2018 and September 30, 2019: December 31, September 30, 2018 2019 Long-term portion of lease liability: Operating $ — $ — Finance — 1,032,243 Total $ — $ 1,032,243
Schedule of Lease Expenses	The following schedule represents the components of lease expense for the three and nine months ended September 30, 2018 and 2019: For the three months ended September 30, For the nine months ended September 30, 2018 2019 2018 2019 Lease cost Finance lease cost Amortization of right-of-use assets $ — $ 134,472 $ — $ 364,401 Interest on lease liabilities — 62,026 — 187,574 Operating lease cost — 318,005 — 954,015 Total $ — $ 514,503 $ — $ 1,505,990
Schedule of Remaining Future Minimum Lease Payments for Finance and Operating Leases	The following schedule sets forth the remaining future minimum lease payments outstanding under finance and operating leases, as well as corresponding remaining sales tax and maintenance obligation payments that are expensed as incurred and due within each respective year ending December 31, as well as the present value of the total amount of the remaining minimum lease payments, as of September 30, 2019: Finance Operating Minimum Maintenance and Minimum Lease Sales Tax Obligation Lease Payments Payments Payments 2019 (remaining) $ 222,245 $ 27,016 $ 362,929 2020 764,533 89,136 855,136 2021 517,927 67,974 — 2022 405,318 57,260 — 2023 263,274 56,799 — Thereafter 58,448 8,241 — Total payments 2,231,745 306,426 1,218,065 Less amount representing interest (423,472 ) — (24,810 ) Present value of payments $ 1,808,273 $ 306,426 $ 1,193,255
Supplemental Cash Flow Information Related to Operating and Finance Leases	The following schedule sets forth supplemental cash flow information related to operating and finance leases as of September 30, 2019: For the three months ended For the nine months ended September 30, 2019 September 30, 2019 Other information Operating cash flows from financing leases $ 62,026 $ 187,574 Operating cash flows from operating leases $ 355,813 $ 1,067,437 Financing cash flows from finance leases $ 101,139 $ 378,389

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Option Activity	A summary of stock option activity for the nine months ended September 30, 2019 is as follows: Weighted Average Weighted Remaining Number of Average Exercise Contractual Shares Price Per Share Term in Years Outstanding at December 31, 2018 195,820 $ 41.41 9.20 Granted 2,664,129 $ 0.91 Exercised — — Cancelled/forfeited/expired (62,293 ) $ 6.43 Outstanding at September 30, 2019 2,797,656 $ 3.62 9.52 Vested and unvested expected to vest at September 30, 2019 2,701,017 $ 3.71 9.52
Assumptions Used for Determining Fair Value of Stock Options Under Black-Scholes Pricing Model	The assumptions used in the Black-Scholes pricing model for stock options granted during the three and nine months ended September 30, 2019 were as follows: Stock and exercise prices $0.81 - $1.03 Expected dividend yield 0.00% Discount rate-bond equivalent yield 1.58% – 2.55% Expected life (in years) 5.00 – 5.96 Expected volatility 128% - 156%
Summary of RSU Activity	A summary of RSU activity for the nine months ended September 30, 2019 is as follows: Weighted Number of Average Grant Shares Date Fair Value Outstanding at December 31, 2018 360 $ 415.80 Granted — — Vested and issued — — Forfeited — — Outstanding at September 30, 2019 360 $ 415.80 Vested and unvested expected to vest at September 30, 2019 360 $ 415.80
Effects of Stock-Based Compensation Related to Equity Awards to Employees and Nonemployees on Condensed Statement of Operations and Comprehensive Loss	The following table presents the effects of stock-based compensation related to equity awards to employees and nonemployees on the unaudited condensed statements of operations and comprehensive loss during the periods presented: For the three months ended For the nine months ended September 30, September 30, 2018 2019 2018 2019 Stock Options Cost of revenues $ 10,150 $ 29,405 $ 37,150 $ 54,625 Research and development expenses 30,247 37,626 103,267 102,742 General and administrative expenses 57,162 168,484 243,593 361,102 Sales and marketing expenses 15,513 62,154 63,594 106,300 Total expenses related to stock options 113,072 297,669 447,604 624,769 RSUs Cost of revenues - - (18,802 ) - Research and development expenses - - 13,576 - General and administrative expenses - - 54,303 - Sales and marketing expenses - - 15,348 - Total stock-based compensation $ 113,072 $ 297,669 $ 512,029 $ 624,769

Common Stock Warrants Outstan_2

Common Stock Warrants Outstanding (Tables)	9 Months Ended
	Sep. 30, 2019
Equity Classified Warrants [Abstract]
Summary of Equity-Classified Common Stock Warrant Activity	A summary of equity-classified common stock warrant activity for the nine months ended September 30, 2019 is as follows: Average Weighted Remaining Number of Average Exercise Contractual Shares Price Per Share Term in Years Outstanding at December 31, 2018 4,694,927 $ 8.55 4.4 Issued 14,662,226 $ 1.23 Exercised (4,155,430 ) 1.20 Expired (4,474 ) 953.06 Outstanding at September 30, 2019 15,197,249 $ 3.08 4.5
Schedule of Equity-Classified Common Stock Warrants, Outstanding	Further information about equity-classified common stock warrants outstanding at September 30, 2019 is as follows: Weighted Weighted Average Average Total Shares Contractual Exercise Price Outstanding Life (in years) $ 1.24 11,601,949 4.7 $ 4.21 3,311,578 3.9 $ 25.50 8,208 3.2 $ 33.00 96,999 2.1 $ 45.00 47,821 2.9 $ 75.00 71,995 3.0 $ 117.00 38,772 1.6 $ 140.00 19,339 0.4 $ 424.80 588 4.6 15,197,249

Net Loss per Common Share (Tabl

Net Loss per Common Share (Tables)	9 Months Ended
	Sep. 30, 2019
Earnings Per Share [Abstract]
Schedule of Anti-Dilutive Securities Excluded from Computations of Diluted Weighted-Average Shares	The following potentially dilutive securities have been excluded from the computations of diluted weighted-average shares outstanding for the periods presented, as they would be anti-dilutive: For the three and nine months ended September 30, 2018 2019 Preferred warrants outstanding (number of common stock equivalents) 17 — Common warrants outstanding 4,814,927 15,197,249 RSUs outstanding 360 360 Convertible preferred stock outstanding (number of common stock equivalents) 2,560,727 471,393 Common options outstanding 114,641 2,797,656 Total anti-dilutive common share equivalents 7,490,672 18,466,658

The Company, Business Activit_4

The Company, Business Activities and Basis of Presentation - Additional Information (Detail)	Jul. 06, 2018shares	Sep. 30, 2019shares	Dec. 31, 2018shares
The Company Business Activities And Basis Of Presentation [Line Items]
Stockholders equity reverse stock split ratio	0.03
Common stock, shares authorized	150,000,000	150,000,000	150,000,000
Description of reverse stock split		On July 6, 2018, the Company’s stockholders approved, and the Company filed, an amendment to the Company’s Certificate of Amendment of Certificate of Incorporation to effect a one-for-thirty reverse stock split of the Company’s outstanding common stock.
ASC 606 [Member]
The Company Business Activities And Basis Of Presentation [Line Items]
Performance obligation, description of timing		The duration of time between accession receipt and delivery of a valid assay result to the ordering physician or entity is typically less than two weeks.
Practical expedient, description		The Company does not adjust the transaction price for the effects of a significant financing component, as at contract inception, the Company expects the collection cycle to be one year or less.
ASC 606 [Member] | Maximum [Member] | Sales and Marketing Expenses [Member]
The Company Business Activities And Basis Of Presentation [Line Items]
Amortization period		1 year

The Company, Business Activit_5

The Company, Business Activities and Basis of Presentation - Composition of Net Revenues Recognized Disaggregated by Source (Detail) - USD ($)		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation Of Revenue [Line Items]
Total net revenues		$ 1,529,262	$ 761,591	$ 3,744,824	$ 2,390,772
Commercial Revenues [Member] | Contracted Payers [Member]
Disaggregation Of Revenue [Line Items]
Total net revenues	[1]	476,101	325,097	1,447,421	1,019,857
Commercial Revenues [Member] | Non-Contracted Payers [Member]
Disaggregation Of Revenue [Line Items]
Total net revenues		956,140	373,018	2,080,018	1,201,869
Development Services Revenues [Member]
Disaggregation Of Revenue [Line Items]
Total net revenues		37,981	$ 63,476	125,169	159,606
Kits and Blood Collection Tubes [Member]
Disaggregation Of Revenue [Line Items]
Total net revenues		$ 59,040		$ 92,216	$ 9,440
[1]	Includes Medicare and Medicare Advantage, as reimbursement amounts are fixed.

The Company, Business Activit_6

The Company, Business Activities and Basis of Presentation - Composition of Net Revenues Recognized Disaggregated by Nature (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
The Company Business Activities And Basis Of Presentation [Line Items]
Total net revenues	$ 1,529,262	$ 761,591	$ 3,744,824	$ 2,390,772
Commercial Revenues [Member] | Net Commercial Revenues Recognized Upon Delivery [Member]
The Company Business Activities And Basis Of Presentation [Line Items]
Total net revenues	1,432,241	698,115	3,527,439	2,221,726
Development Services Revenues [Member]
The Company Business Activities And Basis Of Presentation [Line Items]
Total net revenues	37,981	$ 63,476	125,169	159,606
Kits and Blood Collection Tubes [Member]
The Company Business Activities And Basis Of Presentation [Line Items]
Total net revenues	$ 59,040		$ 92,216	$ 9,440

The Company, Business Activit_7

The Company, Business Activities and Basis of Presentation - Summary of Third-Party Payers That Represent More Than 10% of Total Net Revenues and Total Net Accounts Receivable and Their Related Percentage (Detail)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Customer Concentration Risk [Member] | Net Revenues [Member] | Blue Cross Blue Shield [Member]
Concentration Risk [Line Items]
Concentration risk percentage	25.00%	9.00%	20.00%	14.00%
Customer Concentration Risk [Member] | Net Revenues [Member] | Medicare and Medicare Advantage [Member]
Concentration Risk [Line Items]
Concentration risk percentage	32.00%	40.00%	40.00%	39.00%
Customer Concentration Risk [Member] | Net Revenues [Member] | United Healthcare [Member]
Concentration Risk [Line Items]
Concentration risk percentage	8.00%	6.00%	9.00%	15.00%
Credit Concentration Risk [Member] | Net Accounts Receivable [Member] | Blue Cross Blue Shield [Member]
Concentration Risk [Line Items]
Concentration risk percentage				25.00%	22.00%
Credit Concentration Risk [Member] | Net Accounts Receivable [Member] | Medicare and Medicare Advantage [Member]
Concentration Risk [Line Items]
Concentration risk percentage				17.00%	17.00%
Credit Concentration Risk [Member] | Net Accounts Receivable [Member] | United Healthcare [Member]
Concentration Risk [Line Items]
Concentration risk percentage				13.00%	15.00%

Liquidity and Going Concern U_2

Liquidity and Going Concern Uncertainty- Additional Information (Detail) - USD ($)	Mar. 19, 2019	Mar. 11, 2019	Feb. 12, 2019	Jan. 18, 2019	Sep. 20, 2018	Aug. 13, 2018	Jan. 30, 2018	May 31, 2019	May 31, 2018	Feb. 29, 2016	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Feb. 28, 2019
Liquidity And Managements Plans [Line Items]
Cash											$ 6,539,444						$ 6,539,444		$ 3,423,373
Accumulated deficit											(239,981,882)						(239,981,882)		(220,457,578)
Net loss											(5,691,762)	$ (7,816,012)	$ (5,916,787)	$ (6,047,784)	$ (6,153,101)	$ (6,357,143)	(19,424,558)	$ (18,558,028)	$ (24,600,000)
Aggregate net interest-bearing indebtedness											1,900,000						1,900,000
Aggregate net interest-bearing indebtedness due within one year											909,000						909,000
Other non-interest bearing current liabilities											3,000,000						3,000,000
Unconditional purchase commitment aggregate amount										$ 1,062,500	$ 154,000						$ 154,000
Unconditional purchase commitment payment terms																	Quarterly
Unconditional purchase commitment period																	May 31, 2020
Proceeds from issuance of common stock, net of issuance costs	$ 7,500,000			$ 2,000,000
Proceeds from exercise of common stock warrants								$ 4,800,000									$ 2,513,172	$ 0
Public offering, number of common stock and warrants issued					642,438
Stock price	$ 1.37			$ 2.25	$ 3.285
Exercise price of unregistered warrants	$ 1.25		$ 1.20			$ 4.53														$ 1.20
Aggregate units sold under right offering						11,587
Shares issued in offering	5,950,000			990,000
Warrant exercisable for share of common stock	1					1
Net proceeds from issuance of units, net of issuance expenses					$ 2,200,000	$ 10,100,000
Class of warrant or rights, term	5 years 6 months					5 years	5 years
Proceeds from warrant exercise inducement, net																	$ 2,337,298
Pre-funded Warrants [Member]
Liquidity And Managements Plans [Line Items]
Issuance of warrants to purchase shares of common stock					120,000
Exercise price of unregistered warrants					$ 3.275
Change in exercise price of warrants					0.01
May 2019 Warrant Exercise Inducement Offering [Member]
Liquidity And Managements Plans [Line Items]
Proceeds from warrant exercise inducement, net								2,300,000
Other Warrant Exercises [Member]
Liquidity And Managements Plans [Line Items]
Proceeds from exercise of common stock warrants								2,500,000
Warrant [Member]
Liquidity And Managements Plans [Line Items]
Proceeds from exercise of common stock warrants								$ 2,500,000
Aggregate warrants sold under right offering						2,549,140
Common Stock [Member]
Liquidity And Managements Plans [Line Items]
Preferred Stock convertible into common stock												4,149,445	5,985
Common Stock [Member] | Warrant Exercise Inducement Offering and Other Warrant Exercises [Member]
Liquidity And Managements Plans [Line Items]
Issuance of warrants to purchase shares of common stock								4,200,000
Series A Preferred Stock [Member]
Liquidity And Managements Plans [Line Items]
Shares issued in offering						11,587
Preferred Stock convertible into common stock						471,393
Follow-on Public Offering [Member]
Liquidity And Managements Plans [Line Items]
Proceeds from issuance of common stock, net of issuance costs		$ 592,000	$ 6,600,000				$ 13,300,000
Proceeds from exercise of common stock warrants			$ 0				0
Proceeds from gross exercise of common stock warrants outstanding							$ 1,300,000
Exercisable warrant available price per share							$ 1.20
Exercisable warrant available price per share expiration period							2023-01
Public offering, number of common stock and warrants issued							1,095,153
Stock price		$ 1.20	$ 1.20				$ 13.50
Exercise price of unregistered warrants	$ 1.25		$ 1.20		$ 3.16	$ 4.53	$ 1.20
Shares issued in offering			6,250,000
Class of warrant or rights, term	5 years 6 months		5 years		5 years	5 years	5 years
Purchase of common stock by underwriters to cover overallotments, number of shares		538,867
Shelf Registration Statement [Member]
Liquidity And Managements Plans [Line Items]
Shelf registration statement expiration period									May 31, 2021
Minimum public float limit for offering									$ 75,000,000
Private Placement [Member]
Liquidity And Managements Plans [Line Items]
Exercise price of unregistered warrants					$ 3.16
Warrant exercisable for share of common stock					1
Class of warrant or rights, term					5 years
Over-allotment Option [Member] | Warrant [Member]
Liquidity And Managements Plans [Line Items]
Shares issued in offering			915,000
Minimum [Member]
Liquidity And Managements Plans [Line Items]
Unconditional purchase commitment, quarterly payment amount										$ 62,500
Exercise price of unregistered warrants								$ 1.25
Minimum [Member] | Warrant Exercise Inducement Offering and Other Warrant Exercises [Member]
Liquidity And Managements Plans [Line Items]
Exercise price of unregistered warrants								1.20
Maximum [Member]
Liquidity And Managements Plans [Line Items]
Exercise price of unregistered warrants								1.20
Maximum [Member] | Pre-funded Warrants [Member]
Liquidity And Managements Plans [Line Items]
Issuance of warrants to purchase shares of common stock					120,000
Maximum [Member] | Warrant Exercise Inducement Offering and Other Warrant Exercises [Member]
Liquidity And Managements Plans [Line Items]
Exercise price of unregistered warrants								$ 1.25
Maximum [Member] | Follow-on Public Offering [Member]
Liquidity And Managements Plans [Line Items]
Issuance of warrants to purchase shares of common stock			6,250,000				1,095,153
Maximum [Member] | Shelf Registration Statement [Member]
Liquidity And Managements Plans [Line Items]
Aggregate offering price									$ 50,000,000
Maximum [Member] | Over-allotment Option [Member]
Liquidity And Managements Plans [Line Items]
Issuance of warrants to purchase shares of common stock			937,500

Sales of Equity Securities - Ad

Sales of Equity Securities - Additional Information (Detail) - USD ($)	Jul. 15, 2019	May 30, 2019	May 28, 2019	Mar. 19, 2019	Mar. 11, 2019	Feb. 12, 2019	Jan. 18, 2019	Sep. 20, 2018	Aug. 13, 2018	Jan. 30, 2018	May 31, 2019	May 31, 2018	Sep. 30, 2019	Jun. 30, 2019	Sep. 30, 2019	Sep. 30, 2018	Feb. 28, 2019	Dec. 31, 2018
Class Of Stock [Line Items]
Net cash proceeds from sale of securities				$ 7,500,000			$ 2,000,000
Stock price				$ 1.37			$ 2.25	$ 3.285
Exercise price of warrants				$ 1.25		$ 1.20			$ 4.53								$ 1.20
Class of warrant or rights, term				5 years 6 months					5 years	5 years
Issuance of warrants to purchase shares of common stock, grant date fair value		$ 1,800,000		$ 6,000,000		$ 6,800,000		$ 2,000,000	$ 8,400,000	$ 9,700,000
Aggregate units sold under right offering									11,587
Public offering, number of shares issued				5,950,000			990,000
Warrant exercisable for share of common stock				1					1
Series A Preferred Stock convertible to common stock, conversion price									$ 4.53
Net proceeds from issuance of units, net of issuance expenses								$ 2,200,000	$ 10,100,000
Common stock, par value									$ 0.0001				$ 0.0001		$ 0.0001			$ 0.0001
Public offering, number of common stock and warrants issued								642,438
Proceeds from exercise of common stock warrants											$ 4,800,000				$ 2,513,172	$ 0
Warrant inducement expense													$ 1,800,000		$ 1,800,000
Pre-funded Warrants [Member]
Class Of Stock [Line Items]
Issuance of warrants to purchase shares of common stock								120,000
Exercise price of warrants								$ 3.275
Change in exercise price of warrants								$ 0.01
Investor Warrants [Member]
Class Of Stock [Line Items]
Exercise price of warrants			$ 1.31
Proceeds from exercise of common stock warrants			$ 2,300,000
Number of warrant exercised			2,062,966										0	0
Cash exercise of warrants description			In order to induce the Exercising Holders to cash exercise the Investor Warrants, the Exercise Agreements provided for the issuance of new warrants, or the New Warrants, with such New Warrants to be issued in an amount equal to 75% of the number of Exercised Shares underlying any Investor Warrants that was cash exercised by July 15, 2019. The New Warrants were exercisable upon issuance and terminate on the date that is five-years and six-months following the initial exercise date.
Fair value of warrants issued			$ 1,800,000
Percentage of common stock exercised for exchange of new warrants	75.00%
Warrants exercisable date	Jul. 31, 2019		Jul. 15, 2019
Warrant [Member]
Class Of Stock [Line Items]
Aggregate warrants sold under right offering									2,549,140
Proceeds from exercise of common stock warrants											$ 2,500,000
Number of warrant exercised											2,086,479
Series A Preferred Stock [Member]
Class Of Stock [Line Items]
Public offering, number of shares issued									11,587
Preferred stock stated value per share									$ 1,000
Maximum [Member]
Class Of Stock [Line Items]
Exercise price of warrants											$ 1.20
Maximum [Member] | Pre-funded Warrants [Member]
Class Of Stock [Line Items]
Issuance of warrants to purchase shares of common stock								120,000
Maximum [Member] | Investor Warrants [Member]
Class Of Stock [Line Items]
Warrants exercisable percentage			20.00%
Minimum [Member]
Class Of Stock [Line Items]
Exercise price of warrants											$ 1.25
Follow-on Public Offering [Member]
Class Of Stock [Line Items]
Net cash proceeds from sale of securities					$ 592,000	$ 6,600,000				$ 13,300,000
Private offering, number of common stock and warrants issued						6,250,000				1,095,153
Stock price					$ 1.20	$ 1.20				$ 13.50
Cost directly associated with offering										$ 1,400,000
Exercise price of warrants				$ 1.25		$ 1.20		$ 3.16	$ 4.53	$ 1.20
Class of warrant or rights, term				5 years 6 months		5 years		5 years	5 years	5 years
Issuance of warrants to purchase shares of common stock, grant date fair value										$ 9,700,000
Public offering, number of shares issued						6,250,000
Public offering, number of common stock and warrants issued										1,095,153
Proceeds from exercise of common stock warrants						$ 0				$ 0
Purchase of common stock by underwriters to cover overallotments, number of shares					538,867
Follow-on Public Offering [Member] | Maximum [Member]
Class Of Stock [Line Items]
Issuance of warrants to purchase shares of common stock						6,250,000				1,095,153
Shelf Registration Statement [Member]
Class Of Stock [Line Items]
Shelf registration statement expiration period												May 31, 2021
Minimum public float limit for offering												$ 75,000,000
Shelf Registration Statement [Member] | Maximum [Member]
Class Of Stock [Line Items]
Aggregate offering price												$ 50,000,000
Private Placement [Member]
Class Of Stock [Line Items]
Exercise price of warrants								$ 3.16
Class of warrant or rights, term								5 years
Warrant exercisable for share of common stock								1
Over-allotment Option [Member] | Warrant [Member]
Class Of Stock [Line Items]
Public offering, number of shares issued						915,000
Over-allotment Option [Member] | Maximum [Member]
Class Of Stock [Line Items]
Issuance of warrants to purchase shares of common stock						937,500

Fair Value Measurement - Additi

Fair Value Measurement - Additional Information (Detail) - USD ($)	May 30, 2019	Mar. 19, 2019	Feb. 12, 2019	Sep. 20, 2018	Aug. 13, 2018	Jan. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	May 31, 2019	Feb. 28, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fixed asset purchases as right-of-use asset finance lease obligations							$ 583,000	$ 270,000
Issuance of unregistered warrants to purchase shares of common stock, grant date fair value	$ 1,800,000	$ 6,000,000	$ 6,800,000	$ 2,000,000	$ 8,400,000	$ 9,700,000
Estimated grant date fair value of warrants	$ 1.18	$ 1.01	$ 0.95	$ 2.57	$ 3.30	$ 8.82
Exercise price of unregistered warrants		$ 1.25	1.20		$ 4.53					$ 1.20
Class of warrant or rights, term		5 years 6 months			5 years	5 years
Common stock warrants outstanding, intrinsic value							0
Pre-funded Warrants [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Exercise price of unregistered warrants				$ 3.275
Issuance of warrants to purchase shares of common stock				120,000
Common stock warrants outstanding, intrinsic value				$ 350,000
Follow-on Public Offering [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Issuance of unregistered warrants to purchase shares of common stock, grant date fair value						$ 9,700,000
Exercise price of unregistered warrants		$ 1.25	$ 1.20	$ 3.16	$ 4.53	$ 1.20
Class of warrant or rights, term		5 years 6 months	5 years	5 years	5 years	5 years
Warrant Inducement Transaction [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Exercise price of unregistered warrants	$ 1.31
Class of warrant or rights, term	5 years 6 months
Maximum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Issuance of unregistered warrants to purchase shares of common stock	1,547,226	5,950,000	7,165,000	762,438	2,549,140	1,095,153
Exercise price of unregistered warrants									$ 1.20
Maximum [Member] | Pre-funded Warrants [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Issuance of warrants to purchase shares of common stock				120,000
Maximum [Member] | Follow-on Public Offering [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Issuance of warrants to purchase shares of common stock			6,250,000			1,095,153
Minimum [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Exercise price of unregistered warrants									$ 1.25
Estimated Fair Value Measurements, Nonrecurring [Member] | Level 3 Inputs [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fixed asset purchases as right-of-use asset finance lease obligations							$ 583,000

Fair Value Measurement - Assump

Fair Value Measurement - Assumptions Used for Determining Fair Values of Common Stock Warrants (Detail)	Sep. 30, 2019$ / shares	Mar. 19, 2019$ / shares	Jan. 18, 2019$ / shares	Sep. 20, 2018$ / shares
Warrant Fair Value Black Scholes Method [Line Items]
Beginning stock price		$ 1.37	$ 2.25	$ 3.285
January 30, 2018 Offering [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Beginning stock price	$ 10.17
January 30, 2018 Offering [Member] | Exercise Price [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	15
January 30, 2018 Offering [Member] | Expected Dividend Yield [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	0
January 30, 2018 Offering [Member] | Discount Rate-Bond Equivalent Yield [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	2.48
January 30, 2018 Offering [Member] | Expected Life [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Expected life (in years)	5 years
January 30, 2018 Offering [Member] | Expected Volatility [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	99
August 13, 2018 Rights Offering [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Beginning stock price	$ 3.89
August 13, 2018 Rights Offering [Member] | Exercise Price [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	4.53
August 13, 2018 Rights Offering [Member] | Expected Dividend Yield [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	0
August 13, 2018 Rights Offering [Member] | Discount Rate-Bond Equivalent Yield [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	2.75
August 13, 2018 Rights Offering [Member] | Expected Life [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Expected life (in years)	5 years
August 13, 2018 Rights Offering [Member] | Expected Volatility [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	128.69
September 20, 2018 Offering [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Beginning stock price	$ 2.92
September 20, 2018 Offering [Member] | Exercise Price [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	3.16
September 20, 2018 Offering [Member] | Expected Dividend Yield [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	0
September 20, 2018 Offering [Member] | Discount Rate-Bond Equivalent Yield [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	2.77
September 20, 2018 Offering [Member] | Expected Life [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Expected life (in years)	5 years 6 months
September 20, 2018 Offering [Member] | Expected Volatility [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	130.7
February 12, 2019 Offering [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Beginning stock price	$ 1.05
February 12, 2019 Offering [Member] | Exercise Price [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	1.20
February 12, 2019 Offering [Member] | Expected Dividend Yield [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	0
February 12, 2019 Offering [Member] | Discount Rate-Bond Equivalent Yield [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	2.49
February 12, 2019 Offering [Member] | Expected Life [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Expected life (in years)	5 years
February 12, 2019 Offering [Member] | Expected Volatility [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	147.7
March 19, 2019 Offering [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Beginning stock price	$ 1.12
March 19, 2019 Offering [Member] | Exercise Price [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	1.25
March 19, 2019 Offering [Member] | Expected Dividend Yield [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	0
March 19, 2019 Offering [Member] | Discount Rate-Bond Equivalent Yield [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	2.44
March 19, 2019 Offering [Member] | Expected Life [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Expected life (in years)	5 years 6 months
March 19, 2019 Offering [Member] | Expected Volatility [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	140
May 30, 2019 Warrant Inducement Transaction [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Beginning stock price	$ 1.29
May 30, 2019 Warrant Inducement Transaction [Member] | Exercise Price [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	1.31
May 30, 2019 Warrant Inducement Transaction [Member] | Expected Dividend Yield [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	0
May 30, 2019 Warrant Inducement Transaction [Member] | Discount Rate-Bond Equivalent Yield [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	2.05
May 30, 2019 Warrant Inducement Transaction [Member] | Expected Life [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Expected life (in years)	5 years 6 months
May 30, 2019 Warrant Inducement Transaction [Member] | Expected Volatility [Member]
Warrant Fair Value Black Scholes Method [Line Items]
Exercise price	145.9

Balance Sheet Details - Schedul

Balance Sheet Details - Schedule of Fixed Assets and Accrued Liabilities (Detail) - USD ($)	Sep. 30, 2019	Dec. 31, 2018
Fixed Assets
Machinery and equipment	$ 2,845,053	$ 2,818,583
Furniture and office equipment	156,987	157,391
Computer equipment and software	1,552,981	1,437,408
Leasehold improvements	570,174	570,173
Financed equipment		2,573,955
Construction in process	325,550	116,640
Total fixed assets, gross	5,450,745	7,674,150
Less accumulated depreciation and amortization	(4,125,490)	(4,934,728)
Total fixed assets, net	1,325,255	2,739,422
Accrued Liabilities
Accrued payroll	458,750	255,426
Accrued vacation	566,811	535,682
Accrued bonuses	636,167	712,574
Accrued sales commissions	81,101	62,767
Current portion of deferred rent		158,342
Accrued other	104,155	203,602
Total accrued liabilities	$ 1,846,984	$ 1,928,393

Balance Sheet Details - Additio

Balance Sheet Details - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Disposal of fixed assets			$ 0
Fixed assets acquired			297,877	$ 145,253
Financed equipment gross					$ 2,573,955
Depreciation expense	$ 240,207	$ 223,194	691,191	$ 580,366
ASC Topic 842 [Member]
Fixed assets acquired			350,000
Financed equipment gross	3,075,000		3,075,000		2,574,000
Accumulated depreciation related to financed equipment	$ 1,500,000		$ 1,500,000		$ 1,135,000

April 2014 Credit Facility - Ad

April 2014 Credit Facility - Additional Information (Detail) - USD ($)	May 30, 2019	Mar. 19, 2019	Feb. 12, 2019	Sep. 20, 2018	Aug. 13, 2018	Jan. 30, 2018	Apr. 30, 2014	Dec. 31, 2014	Feb. 28, 2019
Line of Credit Facility [Line Items]
Exercise price of unregistered warrants		$ 1.25	$ 1.20		$ 4.53				$ 1.20
Issuance of unregistered warrants to purchase shares of common stock, grant date fair value	$ 1,800,000	$ 6,000,000	$ 6,800,000	$ 2,000,000	$ 8,400,000	$ 9,700,000
Oxford Finance LLC [Member] | Common Stock [Member]
Line of Credit Facility [Line Items]
Warrant issued to lender							588
Exercise price of unregistered warrants							$ 424.80
Warrant term							10 years
Oxford Finance LLC [Member] | First Term Loan [Member]
Line of Credit Facility [Line Items]
Net cash proceeds on term loan							$ 4,898,000
Line of Credit Facility fees amount payable							$ 50,000
Line of Credit Facility, interest rate during period							7.95%
Percentage of final interest payment due at maturity							5.50%
Line of credit facility, maturity date							Jul. 1, 2018
Issuance costs								$ 102,000
Net proceeds from credit facility								4,898,000
Issuance of unregistered warrants to purchase shares of common stock, grant date fair value								$ 233,000

Leases - Additional Information

Leases - Additional Information (Detail)	Feb. 01, 2019USD ($)	Jan. 31, 2019USD ($)mo	Sep. 30, 2019USD ($)mo	Aug. 31, 2019USD ($)mo	Jul. 31, 2019USD ($)mo	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2019USD ($)	Sep. 30, 2018USD ($)	Jan. 01, 2019USD ($)	Dec. 31, 2018USD ($)
Leases [Line Items]
Finance lease right-of-use assets			$ 1,575,039			$ 1,575,039		$ 1,575,039
Financed equipment											$ 2,573,955
Total amount from equipment financing commitment	$ 149,000		$ 89,000	$ 245,000	$ 100,000
Finance lease transaction, frequency of payments		monthly	monthly	monthly	monthly
Finance lease transaction, number of installments payments | mo		36	60	36	48
Finance lease transaction, monthly installments of principal and interest payments		$ 5,013	$ 1,770	$ 8,253	$ 2,706
Finance lease transaction, total amount to be repaid		$ 180,000	$ 106,000	$ 297,000	$ 130,000	106,000		106,000
Finance lease transaction, commitment period		2022-02	2024-09	2022-08	2023-05
Operating lease monthly payments						355,813		1,067,437
Operating lease, right-of-use asset			$ 1,035,210			1,035,210		1,035,210
Operating lease liability			$ 1,193,255			$ 1,193,255		$ 1,193,255
Finance lease, weighted average remaining lease term			3 years 2 months 8 days			3 years 2 months 8 days		3 years 2 months 8 days
Operating lease, weighted average remaining lease term			10 months 2 days			10 months 2 days		10 months 2 days
Finance lease, weighted average discount rate, percent			20.30%			20.30%		20.30%
Operating lease, weighted average discount rate, percent			4.50%			4.50%		4.50%
Right of use assets in exchange for finance lease liabilities								$ 583,000
ASC Topic 842 [Member]
Leases [Line Items]
Finance lease right-of-use assets										$ 1,400,000
Financed equipment			$ 3,075,000			$ 3,075,000		3,075,000			2,574,000
Accumulated depreciation related to financed equipment			$ 1,500,000			1,500,000		1,500,000			$ 1,135,000
Depreciation expense related to equipment under finance leases						$ 134,000	$ 115,000	$ 365,000	$ 271,000
Operating lease transaction, frequency of payments								monthly cash payment
Operating lease monthly payments								$ 120,000
Operating lease term								Jul. 31, 2020
Operating lease, right-of-use asset										1,930,000
Operating lease liability										$ 2,201,000
Operating lease incremental borrowing rate										4.50%
ASC Topic 842 [Member] | Net Machinery and Equipment [Member]
Leases [Line Items]
Finance lease right-of-use assets										$ 1,400,000
Minimum [Member] | ASC Topic 842 [Member]
Leases [Line Items]
Financed equipment useful life			3 years			3 years		3 years
Maximum [Member] | ASC Topic 842 [Member]
Leases [Line Items]
Financed equipment useful life			7 years			7 years		7 years

Leases - Schedule of Right-Of-U

Leases - Schedule of Right-Of-Use Lease Assets (Detail)	Sep. 30, 2019USD ($)
Lease right-of-use assets:
Operating	$ 1,035,210
Finance	1,575,039
Total	$ 2,610,249

Leases - Schedule of Current Po

Leases - Schedule of Current Portion of Operating and Finance Lease Liabilities (Detail)	Sep. 30, 2019USD ($)
Current portion of lease liability:
Operating	$ 1,193,255
Finance	776,030
Total	$ 1,969,285

Leases - Schedule of Long-Term

Leases - Schedule of Long-Term Portion of Operating and Finance Lease Liabilities (Detail)	Sep. 30, 2019USD ($)
Long-term portion of lease liability:
Finance	$ 1,032,243
Total	$ 1,032,243

Leases - Schedule of Lease Expe

Leases - Schedule of Lease Expense (Detail) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Finance lease cost
Amortization of right-of-use assets	$ 134,472	$ 364,401
Interest on lease liabilities	62,026	187,574
Operating lease cost	318,005	954,015
Total	$ 514,503	$ 1,505,990

Leases - Schedule of Remaining

Leases - Schedule of Remaining Future Minimum Lease Payments for Finance and Operating Leases (Detail)	Sep. 30, 2019USD ($)
Financing Lease Minimum Payment Abstract
2019 (remaining)	$ 222,245
2020	764,533
2021	517,927
2022	405,318
2023	263,274
Thereafter	58,448
Total payments	2,231,745
Less amount representing interest	(423,472)
Present value of payments	1,808,273
Financing Lease Maintenance and Sales Tax Obligation Payments Abstract
2019 (remaining)	27,016
2020	89,136
2021	67,974
2022	57,260
2023	56,799
Thereafter	8,241
Total payments	306,426
Present value of payments	306,426
Operating Lease Minimum Payment Abstract
2019 (remaining)	362,929
2020	855,136
Total payments	1,218,065
Less amount representing interest	(24,810)
Present value of payments	$ 1,193,255

Leases - Supplemental Cash Flow

Leases - Supplemental Cash Flow Information Related to Operating and Finance Leases (Detail) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Sep. 30, 2018
Other information
Operating cash flows from financing leases	$ 62,026	$ 187,574
Operating cash flows from operating leases	355,813	1,067,437
Financing cash flows from finance leases	$ 101,139	$ 378,389	$ 160,111

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail)	Jun. 17, 2019shares	Jun. 28, 2018shares	Sep. 30, 2019USD ($)shares	Sep. 30, 2018	Sep. 30, 2019USD ($)Planshares	Sep. 30, 2018	Apr. 30, 2019shares	Dec. 31, 2018USD ($)shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of equity incentive plans | Plan					2
Total Shares Outstanding			2,797,656		2,797,656			195,820
Unrecognized share-based compensation expense, weighted-average recognition period					3 years 2 months 12 days
Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated forfeitures rate			0.00%	0.00%	0.00%	0.00%
Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated forfeitures rate			8.00%	8.00%	8.00%	8.00%
Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value of options outstanding | $			$ 0		$ 0			$ 0
Intrinsic value of options exercisable | $			0		0			0
Intrinsic value of options vested and unvested expected to vest | $			0		0			$ 0
RSUs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value shares, RSUs outstanding | $			400		400
Intrinsic value amount, RSUs unvested and vested expected to vest | $			$ 400		$ 400
RSUs outstanding			360		360			360
Stock Options and RSUs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized share-based compensation expense, stock options | $			$ 2,545,000		$ 2,545,000
2013 Equity Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock options and RSUs authorized			124,211		124,211
Common stock, shares authorized							2,578,229
2013 Equity Incentive Plan [Member] | Non-inducement Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock options and RSUs authorized			3,064,098		3,064,098
Increase in number of shares of common stock authorized for issuance	2,800,000	146,666
Stock options and RSUs issued					2,711,095
Total Shares Outstanding			2,650,970		2,650,970
Common stock, shares authorized			353,003		353,003
2013 Equity Incentive Plan [Member] | Inducement shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock options and RSUs authorized			118,368		118,368
Stock options and RSUs issued					117,534
Total Shares Outstanding			118,368		118,368
Common stock, shares authorized			0		0

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity (Detail) - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Shares Outstanding, Beginning Balance	195,820
Number of Shares, Granted	2,664,129
Number of Shares, Cancelled/forfeited/expired	(62,293)
Number of Shares Outstanding, Ending Balance	2,797,656	195,820
Number of Shares, Vested and unvested expected to vest, Ending Balance	2,701,017
Weighted Average Exercise Price Per Share, Outstanding, Beginning Balance	$ 41.41
Weighted Average Exercise Price Per Share, Granted	0.91
Weighted Average Exercise Price Per Share, Cancelled/forfeited/expired	6.43
Weighted Average Exercise Price Per Share, Outstanding, Ending Balance	3.62	$ 41.41
Weighted Average Exercise Price Per Share, Vested and unvested expected to vest, Ending Balance	$ 3.71
Weighted Average Remaining Contractual Term in Years, Outstanding	9 years 6 months 7 days	9 years 2 months 12 days
Weighted Average Remaining Contractual Term in Years, Vested and unvested expected to vest	9 years 6 months 7 days

Stock-Based Compensation - Assu

Stock-Based Compensation - Assumptions Used for Determining Fair Value of Stock Options Under Black-Scholes Pricing Model (Detail)	3 Months Ended	9 Months Ended
	Sep. 30, 2019$ / shares	Sep. 30, 2019$ / shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected dividend yield	0.00%	0.00%
Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock and exercise prices	$ 0.81	$ 0.81
Discount rate-bond equivalent yield	1.58%	1.58%
Expected life (in years)	5 years	5 years
Expected volatility	128.00%	128.00%
Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock and exercise prices	$ 1.03	$ 1.03
Discount rate-bond equivalent yield	2.55%	2.55%
Expected life (in years)	5 years 11 months 15 days	5 years 11 months 15 days
Expected volatility	156.00%	156.00%

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of RSU Activity (Detail) - RSUs [Member]	9 Months Ended
	Sep. 30, 2019$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares Outstanding, Beginning Balance | shares	360
Number of Shares, Granted | shares	0
Number of share, Vested and issued | shares	0
Number of share, Forfeited | shares	0
Number of Shares Outstanding, Ending Balance | shares	360
Number of Shares, Vested and unvested expected to vest, Ending Balance | shares	360
Weighted Average Grant Date Fair Value, Outstanding, Beginning Balance | $ / shares	$ 415.80
Weighted Average Grant Date Fair Value, Granted | $ / shares	0
Weighted Average Grant Date Fair Value, Vested and issued | $ / shares	0
Weighted Average Grant Date Fair Value, Forfeited | $ / shares	0
Weighted Average Grant Date Fair Value, Outstanding, Ending Balance | $ / shares	415.80
Weighted Average Grant Date Fair Value, Vested and unvested expected to vest, Ending Balance | $ / shares	$ 415.80

Stock-Based Compensation - Effe

Stock-Based Compensation - Effects of Stock-Based Compensation Related to Equity Awards to Employees and Nonemployees on Condensed Statement of Operations and Comprehensive Loss (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	$ 297,669	$ 113,072	$ 624,769	$ 447,604
Stock Options [Member] | Cost of revenues [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	29,405	10,150	54,625	37,150
Stock Options [Member] | Research and Development Expenses [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	37,626	30,247	102,742	103,267
Stock Options [Member] | General and Administrative Expenses [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	168,484	57,162	361,102	243,593
Stock Options [Member] | Sales and Marketing Expenses [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	62,154	15,513	106,300	63,594
RSUs [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	$ 297,669	$ 113,072	$ 624,769	512,029
RSUs [Member] | Cost of revenues [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation				(18,802)
RSUs [Member] | Research and Development Expenses [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation				13,576
RSUs [Member] | General and Administrative Expenses [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation				54,303
RSUs [Member] | Sales and Marketing Expenses [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation				$ 15,348

Common Stock Warrants Outstan_3

Common Stock Warrants Outstanding - Summary of Equity-Classified Common Stock Warrant Activity (Detail) - Warrants [Member] - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Class Of Warrant Or Right [Line Items]
Number of Shares, Outstanding, Beginning Balance	4,694,927
Number of Shares, Issued	14,662,226
Number of Shares, Exercised	(4,155,430)
Number of Shares, Expired	(4,474)
Number of Shares, Outstanding, Ending Balance	15,197,249	4,694,927
Weighted Average Exercise Price Per Share, Outstanding, Beginning Balance	$ 8.55
Weighted Average Exercise Price Per Share, Issued	1.23
Weighted Average Exercise Price Per Share, Exercised	1.20
Weighted Average Exercise Price Per Share, Expired	953.06
Weighted Average Exercise Price Per Share, Outstanding, Ending Balance	$ 3.08	$ 8.55
Average Remaining Contractual Term (in years)	4 years 6 months	4 years 4 months 24 days

Common Stock Warrants Outstan_4

Common Stock Warrants Outstanding - Equity-Classified Common Stock Warrants, Outstanding (Detail) - $ / shares	9 Months Ended
	Sep. 30, 2019	Mar. 19, 2019	Feb. 28, 2019	Feb. 12, 2019	Dec. 31, 2018	Aug. 13, 2018
Class Of Warrant Or Right [Line Items]
Weighted Average Exercise Price		$ 1.25	$ 1.20	$ 1.20		$ 4.53
Warrant [Member]
Class Of Warrant Or Right [Line Items]
Total Shares Outstanding	15,197,249				4,694,927
Weighted Average Exercise Price 1.24 [Member] | Warrant [Member]
Class Of Warrant Or Right [Line Items]
Weighted Average Exercise Price	$ 1.24
Total Shares Outstanding	11,601,949
Weighted Average Contractual Life (in years)	4 years 8 months 12 days
Weighted Average Exercise Price 4.21 [Member] | Warrant [Member]
Class Of Warrant Or Right [Line Items]
Weighted Average Exercise Price	$ 4.21
Total Shares Outstanding	3,311,578
Weighted Average Contractual Life (in years)	3 years 10 months 24 days
Weighted Average Exercise Price 25.50 [Member] | Warrant [Member]
Class Of Warrant Or Right [Line Items]
Weighted Average Exercise Price	$ 25.50
Total Shares Outstanding	8,208
Weighted Average Contractual Life (in years)	3 years 2 months 12 days
Weighted Average Exercise Price 33.00 [Member] | Warrant [Member]
Class Of Warrant Or Right [Line Items]
Weighted Average Exercise Price	$ 33
Total Shares Outstanding	96,999
Weighted Average Contractual Life (in years)	2 years 1 month 6 days
Weighted Average Exercise Price 45.00 [Member] | Warrant [Member]
Class Of Warrant Or Right [Line Items]
Weighted Average Exercise Price	$ 45
Total Shares Outstanding	47,821
Weighted Average Contractual Life (in years)	2 years 10 months 24 days
Weighted Average Exercise Price 75.00 [Member] | Warrant [Member]
Class Of Warrant Or Right [Line Items]
Weighted Average Exercise Price	$ 75
Total Shares Outstanding	71,995
Weighted Average Contractual Life (in years)	3 years
Weighted Average Exercise Price 117.00 [Member] | Warrant [Member]
Class Of Warrant Or Right [Line Items]
Weighted Average Exercise Price	$ 117
Total Shares Outstanding	38,772
Weighted Average Contractual Life (in years)	1 year 7 months 6 days
Weighted Average Exercise Price 140.00 [Member] | Warrant [Member]
Class Of Warrant Or Right [Line Items]
Weighted Average Exercise Price	$ 140
Total Shares Outstanding	19,339
Weighted Average Contractual Life (in years)	4 months 24 days
Weighted Average Exercise Price 424.80 [Member] | Warrant [Member]
Class Of Warrant Or Right [Line Items]
Weighted Average Exercise Price	$ 424.80
Total Shares Outstanding	588
Weighted Average Contractual Life (in years)	4 years 7 months 6 days

Common Stock Warrants Outstan_5

Common Stock Warrants Outstanding - Additional Information (Detail)	Sep. 30, 2019USD ($)
Warrants And Rights Note Disclosure [Abstract]
Common stock warrants outstanding, intrinsic value	$ 0

Net Loss per Common Share - Add

Net Loss per Common Share - Additional Information (Detail) - Pre-funded Warrants [Member]	Sep. 20, 2018$ / sharesshares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Issuance of warrants to purchase shares of common stock	120,000
Change in exercise price of warrants | $ / shares	$ 0.01
Maximum [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Issuance of warrants to purchase shares of common stock	120,000

Net Loss per Common Share - Sch

Net Loss per Common Share - Schedule of Anti-Dilutive Securities Excluded from Computations of Diluted Weighted-Average Shares (Detail) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive common share equivalents	18,466,658	7,490,672	18,466,658	7,490,672
Convertible Preferred Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive common share equivalents	471,393	2,560,727	471,393	2,560,727
Preferred Warrants Outstanding [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive common share equivalents		17		17
Common Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive common share equivalents	15,197,249	4,814,927	15,197,249	4,814,927
RSUs Outstanding [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive common share equivalents	360	360	360	360
Common Options Outstanding [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive common share equivalents	2,797,656	114,641	2,797,656	114,641

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		9 Months Ended
	Feb. 29, 2016	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Loss Contingencies [Line Items]
Unconditional purchase commitment aggregate amount	$ 1,062,500	$ 154,000		$ 154,000
Unconditional purchase commitment payment terms				Quarterly
Unconditional purchase commitment period				May 31, 2020
Total expense for sales tax and maintenance obligations		35,000	$ 25,000	$ 82,000	$ 75,000
Total amounts for future sales tax and maintenance obligations		306,426		306,426
Accrued Other Liabilities [Member]
Loss Contingencies [Line Items]
Sales tax and maintenance obligations incurred but not paid		$ 71,000		$ 71,000		$ 69,000
Minimum [Member]
Loss Contingencies [Line Items]
Unconditional purchase commitment, quarterly payment amount	$ 62,500

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Aegea Biotechnologies, Inc [Member]
Related Party Transaction [Line Items]
Reimbursement for shared patent costs	$ 0	$ 0	$ 26,000	$ 19,000