Invuity (IVTY) 10-Q 12 Aug 15 2015 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - Jun. 30, 2015 - shares	Total
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q2
Trading Symbol	IVTY
Entity Registrant Name	Invuity, Inc.
Entity Central Index Key	1,393,020
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding	13,305,015

Condensed Balance Sheets

Condensed Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 65,755	$ 6,048
Accounts receivable, net	3,237	2,798
Inventory	4,826	4,271
Prepaid expenses and other current assets	1,115	2,486
Total current assets	74,933	15,603
Restricted cash	1,125	1,125
Property and equipment, net	9,037	8,541
Other non-current assets		55
Total assets	85,095	25,324
Current liabilities:
Accounts payable	2,022	1,075
Accrued and other current liabilities	5,094	4,162
Total current liabilities	7,116	5,237
Deferred rent	2,831	2,676
Convertible preferred stock warrant liability		136
Long-term debt-related party	14,418	9,347
Total liabilities	$ 24,365	$ 17,396
Commitments and contingencies
Convertible preferred stock, $0.001 par value-0 and 6,207,320 shares authorized at June 30, 2015 and December 31, 2014, respectively; 0 and 6,056,403 shares issued and outstanding at June 30, 2015 and December 31, 2014, respectively		$ 73,755
Stockholders' equity (deficit):
Preferred stock, $0.001 par value-10,000,000 and no shares authorized at June 30, 2015 and December 31, 2014, respectively; no shares issued and outstanding at June 30, 2015 and December 31, 2014
Common stock, $0.001 par value-100,000,000 and 9,189,189 shares authorized at June 30, 2015 and December 31, 2014, respectively; 13,305,015 and 711,249 shares issued and outstanding at June 30, 2015 and December 31, 2014, respectively	$ 13	$ 1
Additional paid-in capital	147,132	2,209
Accumulated deficit	(86,415)	(68,037)
Total stockholders' equity (deficit)	60,730	(65,827)
Total liabilities, convertible preferred stock and stockholders' equity (deficit)	$ 85,095	$ 25,324

Condensed Balance Sheets (Paren

Condensed Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Convertible preferred stock, par value	$ 0.001	$ 0.001
Convertible preferred stock, shares authorized	0	6,207,320
Convertible preferred stock, shares issued	0	6,056,403
Convertible preferred stock, shares outstanding	0	6,056,403
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000	0
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	9,189,189
Common stock, shares issued	13,305,015	711,249
Common stock, shares outstanding	13,305,015	711,249

Condensed Statements of Operati

Condensed Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statement [Abstract]
Revenue	$ 4,747	$ 2,816	$ 9,189	$ 4,970
Cost of goods sold	1,936	1,280	3,668	2,027
Gross profit	2,811	1,536	5,521	2,943
Operating expenses:
Selling, general and administrative	9,820	5,339	18,743	9,913
Research and development	1,857	1,310	3,757	2,513
Total operating expenses	11,677	6,649	22,500	12,426
Loss from operations	(8,866)	(5,113)	(16,979)	(9,483)
Interest expense	(504)	(352)	(873)	(722)
Interest and other income (expense), net	24	9	(526)	37
Net loss and comprehensive loss	$ (9,346)	$ (5,456)	$ (18,378)	$ (10,168)
Net loss per common share, basic and diluted	$ (3.20)	$ (8.40)	$ (10.11)	$ (15.75)
Weighted-average shares used to compute net loss per common share, basic and diluted	2,919,823	649,511	1,817,673	645,681

Condensed Statements of Cash Fl

Condensed Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash flows from operating activities:
Net loss	$ (18,378)	$ (10,168)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	819	135
Stock-based compensation	561	323
Changes in fair value of convertible preferred stock warrant liability	472	(1)
Provision for doubtful accounts	89	57
Noncash interest expense	71	29
Accretion of premium on marketable securities		100
Changes in operating assets and liabilities:
Accounts receivable	(528)	(339)
Inventory	(555)	98
Prepaid expenses and other current assets	1,386	(35)
Accounts payable	131	(227)
Accrued and other current liabilities	651	333
Deferred rent	126	(13)
Net cash used in operating activities	(15,155)	(9,708)
Cash flows from investing activities:
Purchases of property and equipment	(2,695)	(214)
Purchases of marketable securities		(17,510)
Maturities of marketable securities		850
Increase in restricted cash		(1,090)
Net cash used in investing activities	(2,695)	(17,964)
Cash flows from financing activities:
Proceeds from issuance of common stock upon initial public offering, net of issuance costs	49,755
Proceeds from issuance of long-term debt -related party, net of issuance costs	5,000	9,800
Payments of long-term debt		(2,500)
Proceeds from issuance of common stock upon exercise of stock options	33	27
Proceeds from issuance of convertible preferred stock, net of issuance costs	22,769	20,806
Net cash provided by financing activities	77,557	28,133
Net increase in cash and cash equivalents	59,707	461
Cash and cash equivalents, beginning of period	6,048	4,953
Cash and cash equivalents, end of period	65,755	5,414
Supplemental disclosures of cash flow information:
Interest paid		275
Interest paid to related party	804	427
Non-cash investing and financing activities:
Purchases of property and equipment in accounts payable and accrued liabilities	82	$ 47
Initial public offering costs in accounts payable and accrued liabilities	2,542
Reclassification of convertible preferred stock warrant liability to additional paid-in capital upon conversion of preferred stock warrants into common stock warrants	$ 608

Organization and Description of

Organization and Description of Business	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
Organization and Description of Business	1. Organization and Description of Business Invuity, Inc. (the “Company”), was incorporated in the state of California on November 29, 2004 and reincorporated in Delaware in May 2015. The Company is a commercial-stage medical technology company which utilizes its proprietary Intelligent Photonics technology to develop single-use and reusable illuminated surgical devices, which provide surgeons with illumination and direct visualization of surgical cavities during open minimally invasive and minimal access procedures. The Company’s facilities are located in San Francisco, California. Reverse Stock Split In May 2015, the Company’s board of directors and its stockholders approved an amendment to the Company’s amended and restated articles of incorporation to effect a reverse split of shares of the Company’s common stock on a 1-for-18.5 basis (the “Reverse Stock Split”). All authorized, issued and outstanding shares of common stock, convertible preferred stock, warrants for common stock and preferred stock, options to purchase common stock and the related per share amounts contained in the financial statements have been retroactively adjusted to reflect this Reverse Stock Split for all periods presented. The Reverse Stock Split was effected on May 27, 2015. Initial Public Offering In June 2015, the Company completed an initial public offering (“IPO”) of its common stock. In connection with its IPO, the Company sold 4,600,000 shares of common stock at $12.00 per share for aggregate net proceeds of $47.2 million after underwriting discounts and commissions and offering costs incurred by the Company. These amounts include the exercise in full by the underwriters of their option to purchase up to 600,000 additional shares of common stock at the same price to cover over-allotments. Upon the effectiveness of the Amended and Restated Certificate of Incorporation of the Company on June 18, 2015, the number of shares of capital stock the Company is authorized to issue was increased to 110,000,000 shares, of which 100,000,000 shares are common stock and 10,000,000 shares are preferred stock. Both the common stock and preferred stock have a par value of $0.001 per share. There are no shares of preferred stock outstanding at June 30, 2015. Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) for interim financial information and in accordance with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements. The unaudited interim condensed financial statements have been prepared on the same basis as the annual financial statements. In the opinion of management, the accompanying unaudited condensed financial statements reflect all adjustments (consisting only of normal recurring adjustments) considered necessary for a fair statement. The information included in this Quarterly Report on Form 10-Q should be read in conjunction with the audited financial statements and notes thereto included in the Company’s prospectus dated June 15, 2015 filed with the SEC pursuant to Rule 424(b) under the Securities Act of 1933, as amended. The results for the three and six-months ended June 30, 2015 are not necessarily indicative of the results expected for the full fiscal year or any other periods. Out-of-Period Adjustments In the three months ended June 30, 2015, the Company recorded an out-of-period adjustment to reverse revenue that the Company had originally recorded in the fourth quarter of 2014 associated with sales to a distributor for military facilities. The correction of this error resulted in an increase to the Company’s net loss of $302,000 for the three and six months ended June 30, 2015 and a corresponding decrease to accounts receivable. The distributor has returned the underlying inventory, and the Company has terminated the relationship with the distributor involved, and started working with a new distributor for military accounts. Management has assessed the impact of the adjustment and does not believe the amount is material to any prior period financial statements, and the impact of correcting the error in the three months ended June 30, 2015 is not material to those financial statements and is not expected to be material to the financial statements for the year ending December 31,2015. As a result, the Company has not restated any prior period amounts. In the three months ended March 31, 2015, the Company recorded an out-of-period adjustment to increase the fair value of the convertible preferred stock warrant liability, which was incorrectly valued at December 31, 2014 due to an error in the expected term assumption. The correction of this error resulted in an increase to the Company’s net loss of $370,000 for the three months ended March 31, 2015 and a corresponding increase to the convertible preferred stock warrant liability. Management has assessed the impact of the adjustment and does not believe that the amount is material to any prior period financial statements, and the impact of correcting the error in the three months ended March 31, 2015 is not material to those financial statements and is not expected to be material to the financial statements for the year ending December 31, 2015. As a result, the Company has not restated any prior period amounts. During the three months ended March 31, 2015, the Company determined that expenses relating to research and development in 2014 had been incorrectly classified within selling, general and administrative expenses, due to an erroneous allocation of departmental expenses. The Company has revised the statement of operations for the year ended December 31, 2014 to correct the classification, which resulted in an increase to research and development expenses of $564,000, with a corresponding decrease to selling, general and administrative expenses. Management has assessed the impact of the correction and has concluded that it is not material to the previously issued statement of operations for the year ended December 31, 2014.

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Use of Estimates The Company’s financial statements have been prepared in conformity with U.S. GAAP. The preparation of the financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, management evaluates its estimates, including those related to revenue recognition, fair value of assets and liabilities, inventory, income taxes, convertible preferred stock and related warrants, common stock prior to the Company’s IPO, and stock-based compensation. Actual results could differ from those estimates and assumptions. Cash Equivalents Cash equivalents consist of short-term, highly liquid investments with original maturities of three months or less from the date of purchase. Cash equivalents consist primarily of amounts invested in money market funds. Restricted Cash Restricted cash represents a certificate of deposit held at a financial institution as collateral for the Company credit cards and a letter of credit related to the Company’s facility lease. Fair Value of Financial Instruments Carrying amounts of the Company’s financial instruments, including cash equivalents, accounts receivable and accounts payable approximate fair value due to their relatively short maturities. As of June 30, 2015 and December 31, 2014, based on Level 2 inputs and the borrowing rates available to the Company for loans with similar terms and consideration of the Company’s credit risk, the carrying value of the Company’s long-term debt approximates its fair value. Deferred Offering Costs Deferred offering costs, primarily consisting of legal, accounting, printer and other direct fees and costs relating to the initial public offering, were capitalized. The deferred offering costs were subsequently offset against the Company’s IPO proceeds upon the closing of the offering in June 2015. As of December 31, 2014, the Company had capitalized $40,000 in deferred offering costs in other non-current assets on the balance sheet. Customer Concentration Significant customers are those which represent 10% or more of the Company’s total revenue for each period presented in the condensed statements of operations and comprehensive loss or 10% or more of the Company’s net accounts receivable balance at each respective balance sheet date. For each significant customer, revenue as a percentage of total revenue was as follows: Revenue Accounts Receivable, net Three Months Ended June 30, Six Months Ended June 30, June 30, December 31, 2015 2014 2015 2014 2015 2014 Customers: Customer A * 14 % * 15 % 11 % 12 % Customer B * * * * * 12 % * Less than 10% Convertible Preferred Stock Warrant Liability Freestanding warrants for shares that were contingently redeemable were classified as liabilities on the balance sheet at their estimated fair value because the shares underlying the warrants may obligate the Company to transfer assets to the holders at a future date under certain circumstances such as a deemed liquidation event. The warrants were subject to re-measurement at each balance sheet date and the change in fair value, if any, was recognized as interest and other income, net in the condensed statements of operations and comprehensive loss. The Company adjusted the liability for changes in fair value until the completion of its IPO, at which time all convertible preferred stock warrants were converted into warrants to purchase common stock and the liability was reclassified to additional paid-in capital. Revenue Recognition The Company’s revenue is generated from the sale of its products to hospitals and medical centers through direct sales representatives and independent sales agents. The Company recognizes revenue when all of the following criteria are met: • persuasive evidence of an arrangement exists; • the sales price is fixed or determinable; • collection of the relevant receivable is reasonably assured at the time of sale; and • delivery has occurred or services have been rendered. The Company recognizes revenue when title to the goods and risk of loss transfers to the customer, which is upon shipment of the product under the Company’s standard terms and conditions. Shipping and handling costs billed to the customer are recorded in revenue. Segment Reporting The Company manages its operations as a single operating segment for the purposes of assessing performance and making operating decisions. All of the Company’s assets are maintained in the United States. The Company derives its revenue from sales to customers in the United States, based upon the billing address of the customer. Net loss per Common Share Basic net loss per common share is calculated by dividing the net loss by the weighted-average number of shares of common stock outstanding during the period, without consideration of potentially dilutive securities. Diluted net loss per common share is the same as basic net loss per common share since the effect of potentially dilutive securities are anti-dilutive. Shares subject to repurchase are excluded from the weighted-average shares. Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”). Areas of revenue recognition that will be affected include, but are not limited to, transfer of control, variable consideration, allocation of transfer pricing, licenses, time value of money, contract costs and disclosures. On July 9, 2015, the FASB deferred the implementation of this standard by one year so that the guidance is effective for fiscal years and interim reporting periods beginning after December 15, 2017, at which time the Company may adopt the new standard under the full retrospective method or the modified retrospective method. The Company is currently evaluating the impact that the adoption of ASU 2014-09 will have on its financial statements and related disclosures. In April 2015, the FASB issued ASU No. 2015-03, Interest-Imputation of Interest In July 2015, the FASB issued ASU 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory. ASU 2015-11 amends guidance on the measurement of inventory from lower of cost or market to net realizable value. The amendment applies to all inventory other than those measured by Last-In-First-Out (LIFO) and the Retail Inventory Method (RIM). The amendment is effective for fiscal years beginning after December 15, 2016, including interim periods within that reporting period. Early adoption is permitted. The Company is currently evaluating the impact, if any, that the adoption of ASU 2015-11 will have on its financial statements and related disclosures.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurements	3. Fair Value Measurements The Company discloses and recognizes the fair value of its assets and liabilities using a hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the reporting date. The hierarchy gives the highest priority to valuations based upon unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to valuations based upon unobservable inputs that are significant to the valuation (Level 3 measurements). The guidance establishes three levels of the fair value hierarchy as follows: Level 1 Level 2 Level 3 The Company’s financial instruments consist of Level 1 assets and Level 3 liabilities. Where quoted prices are available in an active market, securities are classified as Level 1. Level 1 assets consist primarily of highly liquid money market funds that are included in cash and cash equivalents and restricted cash. Level 3 liabilities that were measured at fair value on a recurring basis consisted of the convertible preferred stock warrant liability, which was measured using the probability weighted expected return method that calculated the probability of the Company going public or being acquired, and the option-pricing method for remaining private in the near to mid-term. The fair value of the convertible preferred stock warrants at December 31, 2014 was determined using a hybrid method of the option-pricing model and a probability of various liquidity events required to trigger the conversion of the convertible preferred stock warrants. The scenarios included merger and acquisition events ranging in time to liquidity event of one to three years, an IPO occurring within six months to two years, and dissolution of the Company. At the end of each reporting period, the change in estimated fair value during the period is recorded in interest and other income (expense), net. Generally, increases or decreases in the fair value of the underlying convertible preferred stock would result in a directionally similar impact in the fair value measurement of the warrant liability. The convertible preferred stock warrant liability was remeasured prior to the conversion of the warrants into common stock warrants using an option-pricing model and the following key assumptions: IPO price, expected life of 3.25 to 8.71 years, risk free interest rate of 1.01% to 2.01% and volatility of 35%. Upon completion of the IPO, the convertible preferred stock warrants were converted into common stock warrants and the fair value of the liability of $0.6 million was transferred to additional paid-in capital. The warrants are no longer subject to remeasurement. The following table sets forth the fair value of the Company’s financial assets and liabilities measured at fair value on a recurring basis based on the three-tier fair value hierarchy (in thousands): June 30, 2015 Level 1 Level 2 Level 3 Total Assets Money market funds (a) $ 63,769 $ — $ — $ 63,769 $ 63,769 $ — $ — $ 63,769 December 31, 2014 Level 1 Level 2 Level 3 Total Assets Money market funds (a) $ 5,768 $ — $ — $ 5,768 $ 5,768 $ — $ — $ 5,768 Liabilities Convertible preferred stock warrant liability $ — $ — $ 136 $ 136 $ — $ — $ 136 $ 136 (a) - Balances include $35,000 classified as non-current restricted cash as of June 30, 2015 and December 31, 2014. The following table sets forth a summary of the changes in the fair value of the convertible preferred stock warrant liability, the Company’s Level 3 financial liability, which is measured on a recurring basis (in thousands): Three Months ended Six Months ended June 30, 2015 2014 2015 2014 Beginning balance $ 640 $ 648 $ 136 $ 86 Issuance of convertible preferred stock warrants — — — 572 Change in fair value recorded in interest and other income, net (32 ) 9 472 (1 ) Reclassification from liability to additional paid-in capital upon conversion to common stock warrants at the IPO (608 ) — (608 ) — Ending balance $ — $ 657 $ — $ 657

Balance sheet components

Balance sheet components	6 Months Ended
	Jun. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Balance sheet components	4. Balance sheet components Inventory Inventory consisted of the following (in thousands): June 30, 2015 December 31, 2014 Raw materials $ 702 $ 894 Work-in-process 642 768 Finished goods 3,482 2,609 Total inventory $ 4,826 $ 4,271 Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets consisted of the following (in thousands): June 30, 2015 December 31, 2014 Prepaid expenses $ 803 $ 420 Tenant improvement allowance receivable 299 2,064 Other 13 2 Total prepaid expenses and other current assets $ 1,115 $ 2,486 Property and Equipment, Net Property and equipment, net, consisted of the following (in thousands): June 30, December 31, 2014 Computer equipment and software $ 975 $ 633 Laboratory and manufacturing equipment 1,083 816 Furniture and fixtures 1,440 1,409 Leasehold improvements 6,889 6,541 Total property and equipment, gross 10,387 9,399 Less: accumulated depreciation and amortization (1,350 ) (858 ) Total property and equipment, net $ 9,037 $ 8,541 Depreciation and amortization expense was $421,000 and $68,000 for the three months ended June 30, 2015 and 2014, and $819,000 and $135,000 for the six months ended June 30, 2015 and 2014. Accrued and Other Current Liabilities Accrued and other current liabilities consisted of the following (in thousands): June 30, December 31, 2014 Accrued payroll-related expenses $ 2,005 $ 1,599 Accrued independent sales agent commissions 276 227 Accrued professional fees 2,092 89 Accrued costs for property and equipment 5 1,453 Deferred rent 261 290 Accrued sales and marketing expenses 30 95 Other 425 409 Total accrued and other current liabilities $ 5,094 $ 4,162

Related Party Loan Agreement

Related Party Loan Agreement	6 Months Ended
	Jun. 30, 2015
Related Party Transactions [Abstract]
Related Party Loan Agreement	5. Related Party Loan Agreement In March 2015, the Company drew down the second tranche of $5.0 million from its $15.0 million loan agreement with HealthCare Royalty Partners (“HCRP”), a related party due to its equity ownership interest in the Company. Interest is payable quarterly at a fixed rate of 12.5% per annum with interest-only payments to be made from the effective date of the loan until March 31, 2017. Thereafter, the Company will make principal and interest payments until the maturity of the loan on December 31, 2020. The Company is permitted to make a voluntary prepayment in full, but not in part, prior to December 31, 2020, which prepayment must be made together with accrued and unpaid fixed interest on the amount prepaid and any additional amounts due in respect thereof, including an additional percentage of the aggregate loan amount or outstanding principal amount, depending on the date of prepayment. The Company’s obligations under the loan agreement are secured by a first priority security interest in all of the Company’s assets, other than bank accounts, accounts receivable and inventory. The loan agreement imposes customary affirmative and restrictive covenants, including with respect to fundamental transactions, the incurrence of additional indebtedness or liens and the payment of cash dividends, but does not include any financial covenants. The loan agreement contains a material adverse event clause which provides that an event of default will occur if, among other triggers, there occurs any circumstance that could reasonably be expected to result in a material adverse effect on the Company’s business, operations or condition, or on the Company’s ability to perform its obligations under the loan. As of June 30, 2015, management does not believe that it is probable that the clause will be triggered within the next twelve months, and therefore the debt is classified as long-term. The loan agreement also includes customary representations and warranties, events of defaults and termination provisions. As of December 31, 2014 and June 30, 2015, the Company was in compliance with all covenants.

Credit Facility

Credit Facility	6 Months Ended
	Jun. 30, 2015
Debt Disclosure [Abstract]
Credit Facility	6. Credit Facility In February 2015, the Company entered into an accounts receivable credit facility with SVB that permits the borrowing of the lesser of $7.5 million or an amount representing up to 80% of eligible accounts receivable. The credit facility matures in February 2018 and the Company’s obligations under the credit facility are secured by a first priority security interest in the Company’s bank accounts, accounts receivable, and inventory. Interest on borrowed amounts is payable monthly at the prime rate plus 0.75%. The credit facility imposes customary affirmative and restrictive covenants, including with respect to fundamental transactions, changes to the Company’s business, the incurrence of additional indebtedness or liens and the payment of dividends, but does not include any financial covenants. In addition, the credit facility states that if the Company maintains a net cash balance, defined as unrestricted cash held with SVB less any borrowings on the revolving line of credit, of more than $3.0 million, then all collections will be deposited in the Company’s operating account. If the net cash balance is below $3.0 million, then all collections will be held in an SVB-controlled account and applied to reduce the loan balance. The credit facility also includes customary representations and warranties, events of defaults and termination provisions. As of June 30, 2015, the Company has not drawn down on the credit facility.

Convertible Preferred Stock

Convertible Preferred Stock	6 Months Ended
	Jun. 30, 2015
Text Block [Abstract]
Convertible Preferred Stock	7. Convertible Preferred Stock Convertible preferred stock as of December 31, 2014 consisted of the following (in thousands except share data): December 31, 2014 Shares Net Aggregate Shares Issued and Carrying Liquidation Authorized Outstanding Value Preference Series A 396,605 396,590 $ 2,646 $ 2,715 Series B 493,385 478,718 8,141 8,240 Series C 1,586,392 1,566,352 17,412 17,592 Series D 2,028,236 2,016,929 24,750 25,000 Series E 1,702,702 1,597,814 20,806 21,259 Total 6,207,320 6,056,403 $ 73,755 $ 74,806 In February and March 2015, the Company issued an aggregate of 1,596,212 shares of Series F convertible preferred stock. Upon the closing of the Company’s IPO in June 2015, all shares of convertible preferred stock then outstanding converted into 7,979,332 shares of common stock, which includes an aggregate of 326,717 additional shares of common stock related to anti-dilution adjustments upon conversion of the convertible preferred stock, as follows (in thousands except share data): Shares Net Shares Issued and Carrying As-Converted Authorized Outstanding Value Shares Series A 396,605 396,590 $ 2,646 396,590 Series B 493,385 478,718 8,141 568,615 Series C 1,586,392 1,566,352 17,412 1,666,248 Series D 2,028,236 2,016,929 24,750 2,034,709 Series E 1,702,702 1,597,814 20,806 1,642,002 Series F 1,654,594 1,596,212 22,769 1,671,168 Total 7,861,914 7,652,615 $ 96,524 7,979,332 As of June 30, 2015 there was no convertible preferred stock outstanding.

Stock Option Plans

Stock Option Plans	6 Months Ended
	Jun. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Option Plans	8. Stock Option Plans Pursuant to the Company’s 2005 Stock Incentive Plan (“2005 Plan”), options and restricted stock may be granted to employees, directors and consultants of the Company. Options granted under the Company’s 2005 Plan may be either incentive stock options or nonstatutory stock options. Incentive stock options may be granted to employees with exercise prices of no less than 100% the fair value of the common stock on the grant date and nonstatutory options may be granted to employees, directors or consultants at exercise prices of no less than 85% of the fair value of the common stock on the grant date, as determined by the Board of Directors. All options granted under the 2005 Plan may be exercised before they are vested. Employee stock options generally vest 25% upon one year of continued service to the Company, with the remainder in monthly increments over three additional years. Stock options granted to consultants generally vest over the performance period of the consultancy agreement, ranging from two to four years. Options expire no more than ten years after the date of grant. In connection with the Board of Directors’ and stockholders’ approval of the 2015 Plan, all remaining shares available for future award under the 2005 Plan were transferred to the 2015 Plan, and the 2005 Plan was terminated. In April 2015, the Company’s board of directors and stockholders approved the 2015 Equity Incentive plan (“2015 Plan”), effective June 11, 2015, covering incentive stock options, nonstatutory stock options and restricted stock awards that may be granted to employees, directors and consultants. The number of shares authorized for issuance under the 2015 Plan is 3,535,794 at June 30, 2015 of which 1,665,635 shares were available for grant. The number of shares available for issuance under the 2015 Plan will be increased on the first day of each fiscal year in an amount equal to at least (i) 1,494,272 shares; (ii) five percent of the outstanding shares on the last day of the immediately preceding fiscal year or (iii) such number of shares determined by the Company’s board of directors. Incentive stock options may be granted to employees or directors holding more than 10% of the voting power of all classes of stock of the Company at an exercise price of no less than 110% of the fair value of the common stock on the grant date and to all other employees or directors at an exercise price of no less than 100% of the fair value of the common stock on the grant date. Nonstatutory stock options may be granted to employees, directors and consultants at an exercise price no less than 100% of the fair value of the common stock on the grant date. Employee stock options generally vest 25% upon one year of continued service to the Company, with the remainder in monthly increments over four additional years. Options expire no more than ten years after the date of grant. Any options under the 2015 Plan that expire or otherwise terminate will revert to the 2015 Plan and again become available for issuance. The 2015 Plan also includes the granting of restricted stock, restricted stock units, stock appreciation rights and performance units. The following table summarizes stock option activity under the plans and related information: Options Outstanding Options Options Weighted- Aggregate (in thousands) Balances at December 31, 2014 315,876 1,379,503 $ 2.56 $ 9,483 Options authorized 1,851,517 — Options granted (521,512 ) 521,512 $ 12.48 Options exercised (14,434 ) $ 2.23 Options forfeited 19,754 (19,754 ) $ 3.26 Balances at June 30, 2015 1,665,635 1,866,827 $ 5.33 $ 16,682 Options Exercisable at June 30, 2015 1,866,827 $ 5.33 $ 16,682 Options vested and expected to vest at June 30, 2015 1,754,832 $ 5.10 $ 16,060 The aggregate intrinsic values of options outstanding, exercisable, vested and expected to vest were calculated as the difference between the exercise price of the options and the fair value of the Company’s common stock, as of June 30, 2015 and December 31, 2014. During the three months ended June 30, 2015 and 2014, the Company granted options with a weighted average grant date fair value of $12.48 and $6.91 per share. During the six months ended June 30, 2015 and 2014, the Company granted options with a weighted average grant date fair value of $12.48 and $3.88 per share. The aggregate intrinsic value of options exercised was $47,000 and $1,000 during the three months ended June 30, 2015 and 2014, and $60,000 and $24,000 during the six months ended June 30, 2015 and 2014. The total fair value of options vested was $381,000 and $178,000 for the three months ended June 30, 2015 and 2014, and $546,000 and $262,000 for the six months ended June 30, 2015 and 2014. The weighted-average remaining contractual life of options outstanding was 8.0 and 7.8 years at June 30, 2015 and December 31, 2014. As of June 30, 2015 and December 31, 2014, the weighted-average remaining contractual life was 7.9 and 7.7 years, for vested and expected to vest options. Early Exercise of Stock Options The 2005 Plan allowed for the granting of options that may be exercised before the options have vested. Shares issued as a result of early exercise that have not vested are subject to repurchase by the Company upon termination of the purchaser’s employment or services, at the price paid by the purchaser. The Company’s right to repurchase these shares generally lapses 1/48 of the original grant date amount per month over four years. At June 30, 2015 and December 31, 2014, there were 13,603 and 17,566 shares of common stock outstanding subject to the Company’s right of repurchase at a weighted-average price of $2.42 and $2.34 per share. Stock-Based The fair value of share-based Black-Scholes option- Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Expected term (in years) 5.0-6.32 6.0 5.0-6.32 6.0 Expected volatility 32.8 % 38 % 32.8 % 38 % Risk-free 1.31-1.72 % 1.93 % 1.31-1.72 % 1.91%-1.93 % Dividend yield — — — — Stock-based Black-Scholes Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Expected term (in years) 8.1-9.1 8.0-9.8 8.1-9.1 8.0-10.0 Expected volatility 38 % 38 % 34-38 % 38%-43 % Risk-free 1.9-3.03 % 2.60 % 1.79-3.03 % 2.60%-2.72 % Dividend yield — — — — The following table summarizes stock-based Three Months Ended Six Months Ended 2015 2014 2015 2014 Cost of revenue $ 24 $ 3 $ 41 $ 4 Research and development 86 24 147 34 Selling, general and administrative 278 209 373 285 Total stock-based $ 388 $ 236 $ 561 $ 323 As of June 30, 2015, unrecognized compensation expense related to unvested options, net of estimated forfeitures, was $3.4 million, which the Company expects to recognize on a straight-line weighted-average

Net Loss per Common Share

Net Loss per Common Share	6 Months Ended
	Jun. 30, 2015
Earnings Per Share [Abstract]
Net Loss per Common Share	9. Net Loss per Common Share The Company computes net income (loss) per share of common stock in conformity with the two-class method required for participating securities. The Company considers all series of the Company’s convertible preferred stock to be participating securities as the holders of the convertible preferred stock are entitled to receive a noncumulative dividend on a pari passu basis in the event that a dividend is paid on common stock. In accordance with the two-class method, earnings allocated to convertible preferred stock are excluded from the computation of net income per common share, basic and diluted. The holders of all series of convertible preferred stock do not have a contractual obligation to share in the losses of the Company. As such, the Company’s net losses for the three months and six months ended June 30, 2015 and 2014 were not allocated to these participating securities. As the Company had net losses for all the periods presented, all potentially dilutive common securities were determined to be anti-dilutive. The following table sets forth the computation of the basic and diluted net loss per share (in thousands, except share and per share data): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Numerator: Net loss $ (9,346 ) $ (5,456 ) $ (18,378 ) $ (10,168 ) Denominator: Weighted-average common shares outstanding 2,934,315 672,407 1,833,709 666,896 Less: weighted-average unvested common shares subject to repurchase (14,492 ) (22,896 ) (16,036 ) (21,215 ) Weighted-average shares used to compute net loss per common share, basic and diluted 2,919,823 649,511 1,817,673 645,681 Net loss per common share, basic and diluted $ (3.20 ) $ (8.40 ) $ (10.11 ) $ (15.75 ) The following outstanding shares of potentially dilutive securities have been excluded from diluted net loss per share for the three months and six months ended June 30, 2015 and 2014 because their inclusion would be anti-dilutive: June 30, 2015 2014 Convertible preferred stock on an as-converted basis — 6,246,196 Options to purchase common stock 1,866,827 1,181,970 Warrants to purchase common stock 137,007 3,532 Warrants to purchase convertible preferred stock on an as-converted basis — 134,570 Total 2,003,834 7,566,268

Summary of Significant Accoun15

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The Company’s financial statements have been prepared in conformity with U.S. GAAP. The preparation of the financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, management evaluates its estimates, including those related to revenue recognition, fair value of assets and liabilities, inventory, income taxes, convertible preferred stock and related warrants, common stock prior to the Company’s IPO, and stock-based compensation. Actual results could differ from those estimates and assumptions.
Cash Equivalents	Cash Equivalents Cash equivalents consist of short-term, highly liquid investments with original maturities of three months or less from the date of purchase. Cash equivalents consist primarily of amounts invested in money market funds.
Restricted Cash	Restricted Cash Restricted cash represents a certificate of deposit held at a financial institution as collateral for the Company credit cards and a letter of credit related to the Company’s facility lease.
Fair Value of Financial Instruments	Fair Value of Financial Instruments Carrying amounts of the Company’s financial instruments, including cash equivalents, accounts receivable and accounts payable approximate fair value due to their relatively short maturities. As of June 30, 2015 and December 31, 2014, based on Level 2 inputs and the borrowing rates available to the Company for loans with similar terms and consideration of the Company’s credit risk, the carrying value of the Company’s long-term debt approximates its fair value.
Deferred Offering Costs	Deferred Offering Costs Deferred offering costs, primarily consisting of legal, accounting, printer and other direct fees and costs relating to the initial public offering, were capitalized. The deferred offering costs were subsequently offset against the Company’s IPO proceeds upon the closing of the offering in June 2015. As of December 31, 2014, the Company had capitalized $40,000 in deferred offering costs in other non-current assets on the balance sheet.
Customer Concentration	Customer Concentration Significant customers are those which represent 10% or more of the Company’s total revenue for each period presented in the condensed statements of operations and comprehensive loss or 10% or more of the Company’s net accounts receivable balance at each respective balance sheet date. For each significant customer, revenue as a percentage of total revenue was as follows: Revenue Accounts Receivable, net Three Months Ended June 30, Six Months Ended June 30, June 30, December 31, 2015 2014 2015 2014 2015 2014 Customers: Customer A * 14 % * 15 % 11 % 12 % Customer B * * * * * 12 % * Less than 10%
Convertible Preferred Stock Warrant Liability	Convertible Preferred Stock Warrant Liability Freestanding warrants for shares that were contingently redeemable were classified as liabilities on the balance sheet at their estimated fair value because the shares underlying the warrants may obligate the Company to transfer assets to the holders at a future date under certain circumstances such as a deemed liquidation event. The warrants were subject to re-measurement at each balance sheet date and the change in fair value, if any, was recognized as interest and other income, net in the condensed statements of operations and comprehensive loss. The Company adjusted the liability for changes in fair value until the completion of its IPO, at which time all convertible preferred stock warrants were converted into warrants to purchase common stock and the liability was reclassified to additional paid-in capital.
Revenue Recognition	Revenue Recognition The Company’s revenue is generated from the sale of its products to hospitals and medical centers through direct sales representatives and independent sales agents. The Company recognizes revenue when all of the following criteria are met: • persuasive evidence of an arrangement exists; • the sales price is fixed or determinable; • collection of the relevant receivable is reasonably assured at the time of sale; and • delivery has occurred or services have been rendered. The Company recognizes revenue when title to the goods and risk of loss transfers to the customer, which is upon shipment of the product under the Company’s standard terms and conditions. Shipping and handling costs billed to the customer are recorded in revenue.
Segment Reporting	Segment Reporting The Company manages its operations as a single operating segment for the purposes of assessing performance and making operating decisions. All of the Company’s assets are maintained in the United States. The Company derives its revenue from sales to customers in the United States, based upon the billing address of the customer.
Net loss per Common Share	Net loss per Common Share Basic net loss per common share is calculated by dividing the net loss by the weighted-average number of shares of common stock outstanding during the period, without consideration of potentially dilutive securities. Diluted net loss per common share is the same as basic net loss per common share since the effect of potentially dilutive securities are anti-dilutive. Shares subject to repurchase are excluded from the weighted-average shares.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”). Areas of revenue recognition that will be affected include, but are not limited to, transfer of control, variable consideration, allocation of transfer pricing, licenses, time value of money, contract costs and disclosures. On July 9, 2015, the FASB deferred the implementation of this standard by one year so that the guidance is effective for fiscal years and interim reporting periods beginning after December 15, 2017, at which time the Company may adopt the new standard under the full retrospective method or the modified retrospective method. The Company is currently evaluating the impact that the adoption of ASU 2014-09 will have on its financial statements and related disclosures. In April 2015, the FASB issued ASU No. 2015-03, Interest-Imputation of Interest In July 2015, the FASB issued ASU 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory. ASU 2015-11 amends guidance on the measurement of inventory from lower of cost or market to net realizable value. The amendment applies to all inventory other than those measured by Last-In-First-Out (LIFO) and the Retail Inventory Method (RIM). The amendment is effective for fiscal years beginning after December 15, 2016, including interim periods within that reporting period. Early adoption is permitted. The Company is currently evaluating the impact, if any, that the adoption of ASU 2015-11 will have on its financial statements and related disclosures.

Summary of Significant Accoun16

Summary of Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
Schedule of Revenue as Percentage of Total Revenue for Each Significant Customer	For each significant customer, revenue as a percentage of total revenue was as follows: Revenue Accounts Receivable, net Three Months Ended June 30, Six Months Ended June 30, June 30, December 31, 2015 2014 2015 2014 2015 2014 Customers: Customer A * 14 % * 15 % 11 % 12 % Customer B * * * * * 12 % * Less than 10%

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2015
Fair Value Disclosures [Abstract]
Financial Assets and Liabilities Measured at Fair Value on Recurring Basis Based On Three-Tier Fair Value Hierarchy	The following table sets forth the fair value of the Company’s financial assets and liabilities measured at fair value on a recurring basis based on the three-tier fair value hierarchy (in thousands): June 30, 2015 Level 1 Level 2 Level 3 Total Assets Money market funds (a) $ 63,769 $ — $ — $ 63,769 $ 63,769 $ — $ — $ 63,769 December 31, 2014 Level 1 Level 2 Level 3 Total Assets Money market funds (a) $ 5,768 $ — $ — $ 5,768 $ 5,768 $ — $ — $ 5,768 Liabilities Convertible preferred stock warrant liability $ — $ — $ 136 $ 136 $ — $ — $ 136 $ 136 (a) - Balances include $35,000 classified as non-current restricted cash as of June 30, 2015 and December 31, 2014.
Summary of Changes in Fair Value of Convertible Preferred Stock Warrant Liability	The following table sets forth a summary of the changes in the fair value of the convertible preferred stock warrant liability, the Company’s Level 3 financial liability, which is measured on a recurring basis (in thousands): Three Months ended Six Months ended June 30, 2015 2014 2015 2014 Beginning balance $ 640 $ 648 $ 136 $ 86 Issuance of convertible preferred stock warrants — — — 572 Change in fair value recorded in interest and other income, net (32 ) 9 472 (1 ) Reclassification from liability to additional paid-in capital upon conversion to common stock warrants at the IPO (608 ) — (608 ) — Ending balance $ — $ 657 $ — $ 657

Balance sheet components (Table

Balance sheet components (Tables)	6 Months Ended
	Jun. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Inventory	Inventory consisted of the following (in thousands): June 30, 2015 December 31, 2014 Raw materials $ 702 $ 894 Work-in-process 642 768 Finished goods 3,482 2,609 Total inventory $ 4,826 $ 4,271
Schedule of Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets consisted of the following (in thousands): June 30, 2015 December 31, 2014 Prepaid expenses $ 803 $ 420 Tenant improvement allowance receivable 299 2,064 Other 13 2 Total prepaid expenses and other current assets $ 1,115 $ 2,486
Schedule of Property and Equipment, Net	Property and equipment, net, consisted of the following (in thousands): June 30, December 31, 2014 Computer equipment and software $ 975 $ 633 Laboratory and manufacturing equipment 1,083 816 Furniture and fixtures 1,440 1,409 Leasehold improvements 6,889 6,541 Total property and equipment, gross 10,387 9,399 Less: accumulated depreciation and amortization (1,350 ) (858 ) Total property and equipment, net $ 9,037 $ 8,541
Schedule of Accrued and Other Current Liabilities	Accrued and other current liabilities consisted of the following (in thousands): June 30, December 31, 2014 Accrued payroll-related expenses $ 2,005 $ 1,599 Accrued independent sales agent commissions 276 227 Accrued professional fees 2,092 89 Accrued costs for property and equipment 5 1,453 Deferred rent 261 290 Accrued sales and marketing expenses 30 95 Other 425 409 Total accrued and other current liabilities $ 5,094 $ 4,162

Convertible Preferred Stock (Ta

Convertible Preferred Stock (Tables)	6 Months Ended
	Jun. 30, 2015
Text Block [Abstract]
Components of Convertible Preferred Stock	Convertible preferred stock as of December 31, 2014 consisted of the following (in thousands except share data): December 31, 2014 Shares Net Aggregate Shares Issued and Carrying Liquidation Authorized Outstanding Value Preference Series A 396,605 396,590 $ 2,646 $ 2,715 Series B 493,385 478,718 8,141 8,240 Series C 1,586,392 1,566,352 17,412 17,592 Series D 2,028,236 2,016,929 24,750 25,000 Series E 1,702,702 1,597,814 20,806 21,259 Total 6,207,320 6,056,403 $ 73,755 $ 74,806 Shares Net Shares Issued and Carrying As-Converted Authorized Outstanding Value Shares Series A 396,605 396,590 $ 2,646 396,590 Series B 493,385 478,718 8,141 568,615 Series C 1,586,392 1,566,352 17,412 1,666,248 Series D 2,028,236 2,016,929 24,750 2,034,709 Series E 1,702,702 1,597,814 20,806 1,642,002 Series F 1,654,594 1,596,212 22,769 1,671,168 Total 7,861,914 7,652,615 $ 96,524 7,979,332

Stock Option Plans (Tables)

Stock Option Plans (Tables)	6 Months Ended
	Jun. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Stock Option Activity	The following table summarizes stock option activity under the plans and related information: Options Outstanding Options Options Weighted- Aggregate (in thousands) Balances at December 31, 2014 315,876 1,379,503 $ 2.56 $ 9,483 Options authorized 1,851,517 — Options granted (521,512 ) 521,512 $ 12.48 Options exercised (14,434 ) $ 2.23 Options forfeited 19,754 (19,754 ) $ 3.26 Balances at June 30, 2015 1,665,635 1,866,827 $ 5.33 $ 16,682 Options Exercisable at June 30, 2015 1,866,827 $ 5.33 $ 16,682 Options vested and expected to vest at June 30, 2015 1,754,832 $ 5.10 $ 16,060
Schedule of Assumptions Used in Estimated Fair Value of Share-based Compensation for Options Granted	The fair value of share-based Black-Scholes option- Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Expected term (in years) 5.0-6.32 6.0 5.0-6.32 6.0 Expected volatility 32.8 % 38 % 32.8 % 38 % Risk-free 1.31-1.72 % 1.93 % 1.31-1.72 % 1.91%-1.93 % Dividend yield — — — — Stock-based Black-Scholes Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Expected term (in years) 8.1-9.1 8.0-9.8 8.1-9.1 8.0-10.0 Expected volatility 38 % 38 % 34-38 % 38%-43 % Risk-free 1.9-3.03 % 2.60 % 1.79-3.03 % 2.60%-2.72 % Dividend yield — — — —
Summary of Stock-based Compensation Expense Related to Stock Options Included in Condensed Statements of Operations and Comprehensive Loss	The following table summarizes stock-based Three Months Ended Six Months Ended 2015 2014 2015 2014 Cost of revenue $ 24 $ 3 $ 41 $ 4 Research and development 86 24 147 34 Selling, general and administrative 278 209 373 285 Total stock-based $ 388 $ 236 $ 561 $ 323

Net Loss per Common Share (Tabl

Net Loss per Common Share (Tables)	6 Months Ended
	Jun. 30, 2015
Earnings Per Share [Abstract]
Schedule of Computation of Basic and Diluted Net Loss per Share	The following table sets forth the computation of the basic and diluted net loss per share (in thousands, except share and per share data): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Numerator: Net loss $ (9,346 ) $ (5,456 ) $ (18,378 ) $ (10,168 ) Denominator: Weighted-average common shares outstanding 2,934,315 672,407 1,833,709 666,896 Less: weighted-average unvested common shares subject to repurchase (14,492 ) (22,896 ) (16,036 ) (21,215 ) Weighted-average shares used to compute net loss per common share, basic and diluted 2,919,823 649,511 1,817,673 645,681 Net loss per common share, basic and diluted $ (3.20 ) $ (8.40 ) $ (10.11 ) $ (15.75 )
Schedule of Outstanding Shares of Potentially Dilutive Securities Excluded from Diluted Net Loss per Share	The following outstanding shares of potentially dilutive securities have been excluded from diluted net loss per share for the three months and six months ended June 30, 2015 and 2014 because their inclusion would be anti-dilutive: June 30, 2015 2014 Convertible preferred stock on an as-converted basis — 6,246,196 Options to purchase common stock 1,866,827 1,181,970 Warrants to purchase common stock 137,007 3,532 Warrants to purchase convertible preferred stock on an as-converted basis — 134,570 Total 2,003,834 7,566,268

Organization and Description 22

Organization and Description of Business - Additional Information (Detail) $ / shares in Units, $ in Millions	1 Months Ended		6 Months Ended
	Jun. 30, 2015USD ($)$ / sharesshares	May. 31, 2015	Jun. 30, 2015$ / sharesshares	Jun. 18, 2015$ / sharesshares	Dec. 31, 2014$ / sharesshares
Organization And Nature Of Operations [Line Items]
Capital stock authorized				110,000,000
Common stock, shares authorized	100,000,000		100,000,000	100,000,000	9,189,189
Preferred stock, shares authorized	10,000,000		10,000,000	10,000,000	0
Common stock, par value | $ / shares	$ 0.001		$ 0.001	$ 0.001	$ 0.001
Preferred stock, par value | $ / shares	$ 0.001		$ 0.001	$ 0.001	$ 0.001
Preferred stock, shares outstanding	0		0		0
Common Stock [Member]
Organization And Nature Of Operations [Line Items]
Description reverse stock split			In May 2015, the Company’s board of directors and its stockholders approved an amendment to the Company’s amended and restated articles of incorporation to effect a reverse split of shares of the Company’s common stock on a 1-for-18.5 basis (the “Reverse Stock Split”). All authorized, issued and outstanding shares of common stock, convertible preferred stock, warrants for common stock and preferred stock, options to purchase common stock and the related per share amounts contained in the financial statements have been retroactively adjusted to reflect this Reverse Stock Split for all periods presented. The Reverse Stock Split was effected on May 27, 2015.
Reverse stock split ratio		0.0541
Convertible preferred stock converted into shares of common stock	7,979,332		7,979,332
Common Stock [Member] | IPO [Member]
Organization And Nature Of Operations [Line Items]
Stock issued, shares	4,600,000
Public offering price | $ / shares	$ 12		$ 12
Stock issued, value | $	$ 47.2
Option to purchase additional shares	600,000
Convertible preferred stock converted into shares of common stock	7,979,332		7,979,332

Organization and Description 23

Organization and Description of Business - Additional Information 1 (Detail) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net loss	$ (9,346)		$ (5,456)	$ (18,378)	$ (10,168)
Accounts receivable, net	3,237			3,237		$ 2,798
Convertible preferred stock warrant liability						$ 136
Research and development	1,857		1,310	3,757	2,513
Selling, general and administrative	9,820		$ 5,339	18,743	$ 9,913
Error Correction [Member] | Restatement Adjustment [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net loss	(302)	$ (370)		(302)
Accounts receivable, net	$ (302)			$ (302)
Convertible preferred stock warrant liability		370
Research and development		564
Selling, general and administrative		$ (564)

Summary of Significant Accoun24

Summary of Significant Accounting Policies - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2015Segments	Dec. 31, 2014USD ($)
Accounting Policies [Abstract]
Deferred offering costs | $		$ 40,000
Number of operating segments	1

Summary of Significant Accoun25

Summary of Significant Accounting Policies - Schedule of Revenue as Percentage of Total Revenue for Each Significant Customer (Detail)	3 Months Ended	6 Months Ended		12 Months Ended
	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Customer Concentration Risk [Member] | Customera [Member] | Revenue [Member]
Concentration Risk [Line Items]
Customer concentration, percentage	14.00%		15.00%
Credit Concentration Risk [Member] | Customera [Member] | Accounts Receivable, net [Member]
Concentration Risk [Line Items]
Customer concentration, percentage		11.00%		12.00%
Credit Concentration Risk [Member] | Customer B [Member] | Accounts Receivable, net [Member]
Concentration Risk [Line Items]
Customer concentration, percentage				12.00%

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - 6 months ended Jun. 30, 2015 - USD ($) $ in Thousands	Total
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Reclassification of convertible preferred stock warrant liability to additional paid-in capital upon conversion of preferred stock warrants into common stock warrants	$ 608
Level 3 [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value assumptions, volatility rate	35.00%
Reclassification of convertible preferred stock warrant liability to additional paid-in capital upon conversion of preferred stock warrants into common stock warrants	$ 600
Level 3 [Member] | Recurring [Member] | Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value assumptions, expected life	3 years 3 months
Fair value assumptions, IPO period	6 months
Fair value assumptions, risk free interest rate	1.01%
Fair value assumptions, liquidity event period	1 year
Level 3 [Member] | Recurring [Member] | Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value assumptions, expected life	8 years 8 months 16 days
Fair value assumptions, IPO period	2 years
Fair value assumptions, risk free interest rate	2.01%
Fair value assumptions, liquidity event period	3 years

Fair Value Measurements - Finan

Fair Value Measurements - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis Based On Three-Tier Fair Value Hierarchy (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Assets
Assets	$ 63,769	$ 5,768
Liabilities
Liabilities		136
Convertible Preferred Stock Warrant [Member]
Liabilities
Liabilities		136
Money Market Funds [Member]
Assets
Assets	63,769	5,768
Level 1 [Member] | Recurring [Member]
Assets
Assets	63,769	5,768
Level 1 [Member] | Money Market Funds [Member] | Recurring [Member]
Assets
Assets	$ 63,769	5,768
Level 3 [Member] | Recurring [Member]
Liabilities
Liabilities		136
Level 3 [Member] | Recurring [Member] | Convertible Preferred Stock Warrant [Member]
Liabilities
Liabilities		$ 136

Fair Value Measurements - Fin28

Fair Value Measurements - Financial Assets and Liabilities Measured at Fair Value on Recurring Basis Based On Three-Tier Fair Value Hierarchy (Parenthetical) (Detail) - USD ($)	Jun. 30, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	$ 63,769,000	$ 5,768,000
Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	63,769,000	5,768,000
Money Market Funds [Member] | Restricted Cash And Cash Equivalents-Long-Term [Member] | Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	$ 35,000	$ 35,000

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Changes in Fair Value of Convertible Preferred Stock Warrant Liability (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Fair Value Disclosures [Abstract]
Beginning balance	$ 640	$ 648	$ 136	$ 86
Issuance of convertible preferred stock warrants				572
Change in fair value recorded in interest and other income, net	(32)	9	472	(1)
Reclassification from liability to additional paid-in capital upon conversion to common stock warrants at the IPO	$ (608)		$ (608)
Ending balance		$ 657		$ 657

Balance sheet components - Sche

Balance sheet components - Schedule of Inventory (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Inventory Disclosure [Abstract]
Raw materials	$ 702	$ 894
Work-in-process	642	768
Finished goods	3,482	2,609
Total inventory	$ 4,826	$ 4,271

Balance sheet components - Sc31

Balance sheet components - Schedule of Prepaid Expenses and Other Current Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid expenses	$ 803	$ 420
Tenant improvement allowance receivable	299	2,064
Other	13	2
Total prepaid expenses and other current assets	$ 1,115	$ 2,486

Balance sheet components - Sc32

Balance sheet components - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 10,387	$ 9,399
Less: accumulated depreciation and amortization	(1,350)	(858)
Total property and equipment, net	9,037	8,541
Computer Equipment and Software [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	975	633
Laboratory and Manufacturing Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	1,083	816
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	1,440	1,409
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 6,889	$ 6,541

Balance sheet components - Addi

Balance sheet components - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Property, Plant and Equipment [Abstract]
Depreciation and amortization	$ 421	$ 68	$ 819	$ 135

Balance sheet components - Sc34

Balance sheet components - Schedule of Accrued and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Accrued payroll-related expenses	$ 2,005	$ 1,599
Accrued independent sales agent commissions	276	227
Accrued professional fees	2,092	89
Accrued costs for property and equipment	5	1,453
Deferred rent	261	290
Accrued sales and marketing expenses	30	95
Other	425	409
Total accrued and other current liabilities	$ 5,094	$ 4,162

Related Party Loan Agreement -

Related Party Loan Agreement - Additional Information (Detail) - HealthCare Royalty Partners [Member] - Loans Payable [Member] - Loan Agreement [Member] - USD ($) $ in Millions	1 Months Ended	6 Months Ended
	Mar. 31, 2015	Jun. 30, 2015
Related Party Transaction [Line Items]
Debt instrument, drawn amount	$ 5
Debt instrument, amount		$ 15
Debt instrument, fixed interest rate		12.50%
Debt instrument, payment terms		Interest is payable quarterly at a fixed rate of 12.5% per annum with interest-only payments to be made from the effective date of the loan until March 31, 2017. Thereafter, the Company will make principal and interest payments until the maturity of the loan on December 31, 2020. The Company is permitted to make a voluntary prepayment in full, but not in part, prior to December 31, 2020, which prepayment must be made together with accrued and unpaid fixed interest on the amount prepaid and any additional amounts due in respect thereof, including an additional percentage of the aggregate loan amount or outstanding principal amount, depending on the date of prepayment.
Debt instrument, maturity date		Dec. 31, 2020

Credit Facility - Additional In

Credit Facility - Additional Information (Detail) - Revolving Credit Facility [Member] - SVB [Member] - Accounts Receivable Credit Facility [Member] - USD ($)	6 Months Ended
	Jun. 30, 2015	Feb. 28, 2015
Line of Credit Facility [Line Items]
Credit facility, maximum borrowing capacity		$ 7,500,000
Credit facility, percentage of maximum borrowings on eligible accounts receivable		80.00%
Line of credit facility maturity month and year	2018-02
Credit facility, interest rate description	Interest on borrowed amounts is payable monthly at the prime rate plus 0.75%.
Credit facility, covenant terms	The credit facility states that if the Company maintains a net cash balance, defined as unrestricted cash held with SVB less any borrowings on the revolving line of credit, of more than $3.0 million, then all collections will be deposited in the Company's operating account. If the net cash balance is below $3.0 million, then all collections will be held in an SVB-controlled account and applied to reduce the loan balance.
Credit facility, net cash balance		$ 3,000,000
Credit facility, frequency of interest payment	Monthly
Prime Rate [Member]
Line of Credit Facility [Line Items]
Credit facility, monthly interest rate in addition to prime rate	0.75%

Convertible Preferred Stock - C

Convertible Preferred Stock - Components of Convertible Preferred Stock (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Jun. 14, 2015	Dec. 31, 2014
Temporary Equity [Line Items]
Convertible preferred stock, shares authorized	0	7,861,914	6,207,320
Convertible preferred stock, shares issued	0	7,652,615	6,056,403
Convertible preferred stock, net carrying value		$ 96,524	$ 73,755
Convertible preferred stock, aggregate liquidation preference			$ 74,806
Convertible preferred stock, as-converted shares		7,979,332
Convertible preferred stock, shares outstanding	0	7,652,615	6,056,403
Series A Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible preferred stock, shares authorized		396,605	396,605
Convertible preferred stock, shares issued		396,590	396,590
Convertible preferred stock, net carrying value		$ 2,646	$ 2,646
Convertible preferred stock, aggregate liquidation preference			$ 2,715
Convertible preferred stock, as-converted shares		396,590
Convertible preferred stock, shares outstanding		396,590	396,590
Series B Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible preferred stock, shares authorized		493,385	493,385
Convertible preferred stock, shares issued		478,718	478,718
Convertible preferred stock, net carrying value		$ 8,141	$ 8,141
Convertible preferred stock, aggregate liquidation preference			$ 8,240
Convertible preferred stock, as-converted shares		568,615
Convertible preferred stock, shares outstanding		478,718	478,718
Series C Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible preferred stock, shares authorized		1,586,392	1,586,392
Convertible preferred stock, shares issued		1,566,352	1,566,352
Convertible preferred stock, net carrying value		$ 17,412	$ 17,412
Convertible preferred stock, aggregate liquidation preference			$ 17,592
Convertible preferred stock, as-converted shares		1,666,248
Convertible preferred stock, shares outstanding		1,566,352	1,566,352
Series D Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible preferred stock, shares authorized		2,028,236	2,028,236
Convertible preferred stock, shares issued		2,016,929	2,016,929
Convertible preferred stock, net carrying value		$ 24,750	$ 24,750
Convertible preferred stock, aggregate liquidation preference			$ 25,000
Convertible preferred stock, as-converted shares		2,034,709
Convertible preferred stock, shares outstanding		2,016,929	2,016,929
Series E Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible preferred stock, shares authorized		1,702,702	1,702,702
Convertible preferred stock, shares issued		1,597,814	1,597,814
Convertible preferred stock, net carrying value		$ 20,806	$ 20,806
Convertible preferred stock, aggregate liquidation preference			$ 21,259
Convertible preferred stock, as-converted shares		1,642,002
Convertible preferred stock, shares outstanding		1,597,814	1,597,814
Series F Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible preferred stock, shares authorized		1,654,594
Convertible preferred stock, shares issued		1,596,212
Convertible preferred stock, net carrying value		$ 22,769
Convertible preferred stock, as-converted shares		1,671,168
Convertible preferred stock, shares outstanding		1,596,212

Convertible Preferred Stock - A

Convertible Preferred Stock - Additional Information (Detail) - shares	2 Months Ended
	Mar. 31, 2015	Jun. 30, 2015	Jun. 14, 2015	Dec. 31, 2014
Temporary Equity [Line Items]
Convertible preferred stock, shares outstanding		0	7,652,615	6,056,403
Series F Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Convertible preferred stock, shares issued during period	1,596,212
Convertible preferred stock, shares outstanding			1,596,212
Common Stock [Member]
Temporary Equity [Line Items]
Convertible preferred stock converted into shares of common stock		7,979,332
Common Stock [Member] | Anti-dilution Adjustments [Member]
Temporary Equity [Line Items]
Convertible preferred stock converted into shares of common stock		326,717

Stock Option Plans - Additional

Stock Option Plans - Additional Information (Detail) - shares	6 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant	1,665,635	315,876
2005 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting, description	Employee stock options generally vest 25% upon one year of continued service to the Company, with the remainder in monthly increments over three additional years. Stock options granted to consultants generally vest over the performance period of the consultancy agreement, ranging from two to four years. Options expire no more than ten years after the date of grant.
2005 Plan [Member] | Incentive Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of stock option granted on fair value of common stock at grant date	100.00%
2005 Plan [Member] | Nonstatutory Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of stock option granted on fair value of common stock at grant date	85.00%
2005 Plan [Member] | Employee [Member] | Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting, percentage	25.00%
Stock option vesting, term	1 year
2005 Plan [Member] | Employee [Member] | Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting, term	3 years
2005 Plan [Member] | Minimum [Member] | Consultants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting, term	2 years
2005 Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option expiration period	10 years
2005 Plan [Member] | Maximum [Member] | Consultants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting, term	4 years
2015 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting, description	Employee stock options generally vest 25% upon one year of continued service to the Company, with the remainder in monthly increments over four additional years. Options expire no more than ten years after the date of grant.
Number of shares authorized for issuance	3,535,794
Number of shares available for grant	1,665,635
Increase in number of shares available for issuance, description	The number of shares authorized for issuance under the 2015 Plan is 3,535,794 at June 30, 2015 of which 1,665,635 shares were available for grant. The number of shares available for issuance under the 2015 Plan will be increased on the first day of each fiscal year in an amount equal to at least (i) 1,494,272 shares; (ii) five percent of the outstanding shares on the last day of the immediately preceding fiscal year or (iii) such number of shares determined by the Company's board of directors.
2015 Plan [Member] | Incentive Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option granted to employees or director upon minimum percentage of voting right	10.00%
2015 Plan [Member] | Employee [Member] | Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting, percentage	25.00%
Stock option vesting, term	1 year
2015 Plan [Member] | Employee [Member] | Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting, term	4 years
2015 Plan [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in number of shares available for issuance	1,494,272
Increase in number of shares available for issuance, percentage	5.00%
2015 Plan [Member] | Minimum [Member] | Employees or Directors Holding Less Than 10% of Voting Power [Member] | Incentive Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of fair value of common stock on grant date	110.00%
2015 Plan [Member] | Minimum [Member] | Employees or Directors Holding More Than 10% of Voting Power [Member] | Incentive Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of fair value of common stock on grant date	100.00%
2015 Plan [Member] | Minimum [Member] | Employees, Directors and Consultants [Member] | Nonstatutory Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of fair value of common stock on grant date	100.00%
2015 Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option expiration period	10 years

Stock Option Plans - Summary of

Stock Option Plans - Summary of Stock Option Activity (Detail) - Jun. 30, 2015 - USD ($) $ / shares in Units, $ in Thousands	Total
Compensation Related Costs [Abstract]
Options Available for Grant, Beginning Balances	315,876
Options Available for Grant, Options authorized	1,851,517
Options Available for Grant, Options granted	(521,512)
Options Available for Grant, Options forfeited	19,754
Options Available for Grant, Ending Balances	1,665,635
Options Outstanding, Beginning Balances	1,379,503
Options Outstanding, Options granted	521,512
Options Outstanding, Options exercised	(14,434)
Options Outstanding, Options forfeited	(19,754)
Options Outstanding, Ending Balances	1,866,827
Options Outstanding, Options Exercisable	1,866,827
Options Outstanding, Options vested and expected to vest	1,754,832
Weighted Average Exercise Price Per Share, Beginning Balances	$ 2.56
Weighted Average Exercise Price Per Share, granted	12.48
Weighted Average Exercise Price Per Share, exercised	2.23
Weighted Average Exercise Price Per Share, forfeited	3.26
Weighted Average Exercise Price Per Share, Ending Balances	5.33
Weighted Average Exercise Price Per Share, Options Exercisable	5.33
Weighted Average Exercise Price Per Share, Options vested and expected to vest	$ 5.10
Aggregate Intrinsic Value, Beginning Balances	$ 9,483
Aggregate Intrinsic Value , Ending Balances	16,682
Aggregate Intrinsic Value, Options Exercisable	16,682
Aggregate Intrinsic Value, Options vested and expected to vest	$ 16,060

Stock Option Plans - Addition41

Stock Option Plans - Additional Information 1 (Detail) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Compensation Related Costs [Abstract]
Weighted average grant date fair value of options, granted	$ 12.48	$ 6.91	$ 12.48	$ 3.88
Aggregate intrinsic value of options exercised	$ 47,000	$ 1,000	$ 60,000	$ 24,000
Fair value of option vested	$ 381,000	$ 178,000	$ 546,000	$ 262,000
Weighted-average remaining contractual life of options outstanding			8 years		7 years 9 months 18 days
Weighted-average remaining contractual life of options outstanding, vested and expected to vest			7 years 10 months 24 days		7 years 8 months 12 days
Stock option repurchase, term			4 years
Common stock outstanding, right to repurchase	13,603		13,603		17,566
Weighted average price of stock repurchase	$ 2.42		$ 2.42		$ 2.34
Right to repurchase of shares, term			The Company's right to repurchase these shares generally lapses 1/48 of the original grant date amount per month over four years.
Unrecognized compensation expense related to unvested options	$ 3,400,000		$ 3,400,000
Weighted-average expected period to recognize of compensation expense, term			3 years 6 months

Stock Option Plans - Schedule o

Stock Option Plans - Schedule of Assumptions Used in Estimated Fair Value of Share-based Compensation for Options Granted (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Employees and Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)		6 years		6 years
Expected volatility	32.80%	38.00%	32.80%	38.00%
Risk-free interest rate		1.93%
Dividend yield	0.00%	0.00%	0.00%	0.00%
Employees and Directors [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	5 years		5 years
Risk-free interest rate	1.31%		1.31%	1.91%
Employees and Directors [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	6 years 3 months 26 days		6 years 3 months 26 days
Risk-free interest rate	1.72%		1.72%	1.93%
Non-employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	38.00%	38.00%
Risk-free interest rate		2.60%
Dividend yield	0.00%	0.00%	0.00%	0.00%
Non-employees [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	8 years 1 month 6 days	8 years	8 years 1 month 6 days	8 years
Expected volatility			34.00%	38.00%
Risk-free interest rate	1.90%		1.79%	2.60%
Non-employees [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	9 years 1 month 6 days	9 years 9 months 18 days	9 years 1 month 6 days	10 years
Expected volatility			38.00%	43.00%
Risk-free interest rate	3.03%		3.03%	2.72%

Stock Option Plans - Summary 43

Stock Option Plans - Summary of Stock-based Compensation Expense Related to Stock Options Included in Condensed Statements of Operations and Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 388	$ 236	$ 561	$ 323
Cost of Revenue [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	24	3	41	4
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	86	24	147	34
Selling, General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 278	$ 209	$ 373	$ 285

Net Loss per Common Share - Sch

Net Loss per Common Share - Schedule of Computation of Basic and Diluted Net Loss per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Numerator:
Net loss	$ (9,346)	$ (5,456)	$ (18,378)	$ (10,168)
Denominator:
Weighted-average common shares outstanding	2,934,315	672,407	1,833,709	666,896
Less: weighted-average unvested common shares subject to repurchase	(14,492)	(22,896)	(16,036)	(21,215)
Weighted-average shares used to compute net loss per common share, basic and diluted	2,919,823	649,511	1,817,673	645,681
Net loss per common share, basic and diluted	$ (3.20)	$ (8.40)	$ (10.11)	$ (15.75)

Net Loss per Common Share - S45

Net Loss per Common Share - Schedule of Outstanding Shares of Potentially Dilutive Securities Excluded from Diluted Net Loss per Share (Detail) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share	2,003,834	7,566,268	2,003,834	7,566,268
Convertible Preferred Stock on an as-Converted Basis [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share		6,246,196		6,246,196
Options To Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share	1,866,827	1,181,970	1,866,827	1,181,970
Warrants to Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share	137,007	3,532	137,007	3,532
Warrants to Purchase Convertible Preferred Stock on an as-Converted Basis [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share		134,570		134,570