Evoke Pharma (EVOK) 10-K 25 Mar 14 2013 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2013	Mar. 20, 2014
Document And Entity Information [Abstract]	'	'
Document Type	'10-K	'
Amendment Flag	'false	'
Document Period End Date	31-Dec-13	'
Document Fiscal Year Focus	'2013	'
Document Fiscal Period Focus	'FY	'
Trading Symbol	'EVOK	'
Entity Registrant Name	'Evoke Pharma Inc	'
Entity Central Index Key	'0001403708	'
Current Fiscal Year End Date	'--12-31	'
Entity Well-known Seasoned Issuer	'No	'
Entity Current Reporting Status	'Yes	'
Entity Voluntary Filers	'No	'
Entity Filer Category	'Smaller Reporting Company	'
Entity Common Stock, Shares Outstanding	'	6,099,547
Entity Public Float	'	$27,627,705

Balance_Sheets

Balance Sheets (USD $)	Dec. 31, 2013	Dec. 31, 2012
Current Assets:	'	'
Cash and cash equivalents	$24,196,691	$116,013
Prepaid expenses	234,262	'
Total current assets	24,430,953	116,013
Other assets	555,505	'
Total assets	24,986,458	116,013
Current Liabilities:	'	'
Accounts payable and accrued expenses	284,915	96,798
Accrued compensation	557,399	417,611
Warrant liability	'	56,000
Current portion of long-term debt	1,442,592	'
Total current liabilities	2,284,906	570,409
Deferred rent expense	6,830	0
Long-term debt, net of current portion	1,511,461	979,792
Total liabilities	3,803,197	1,550,201
Commitments and contingencies	'	'
Stockholders' equity (deficit):	'	'
Preferred stock, value	'	'
Common stock, $0.0001 par value; authorized shares - 50,000,000 at December 31, 2013 and 20,000,000 at December 31, 2012; issued and outstanding shares - 6,096,752 at December 31, 2013 and 1,242,750 at December 31, 2012	610	124
Additional paid-in capital	43,874,119	195,525
Deficit accumulated during the development stage	-22,691,468	-19,855,003
Total stockholders' equity (deficit)	21,183,261	-19,659,354
Total liabilities, convertible preferred stock and stockholders' equity (deficit)	24,986,458	116,013
Series A Convertible Preferred Stock [Member]	'	'
Stockholders' equity (deficit):	'	'
Preferred stock, value	'	$18,225,166

Balance_Sheets_Parenthetical

Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Preferred stock, par value	$0.00	'
Preferred stock, shares authorized	5,000,000	0
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$0.00	$0.00
Common stock, shares authorized	50,000,000	20,000,000
Common stock, shares issued	6,096,752	1,242,750
Common stock, shares outstanding	6,096,752	1,242,750
Series A Convertible Preferred Stock [Member]	'	'
Preferred stock, par value	'	$0.00
Preferred stock, shares authorized	0	12,305,068
Preferred stock, shares issued	0	12,195,068
Preferred stock, shares outstanding	0	12,195,068
Preferred stock, liquidation preference value	$0	$18,292,602

Statements_of_Operations_and_C

Statements of Operations and Comprehensive Loss (USD $)	12 Months Ended			83 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013
Operating expenses:	'	'	'	'
Research and development	$956,980	$1,165,645	$1,844,044	$16,948,509
General and administrative	1,644,848	836,781	570,524	4,949,381
Purchase of in-process research and development	'	'	'	650,000
Total operating expenses	2,601,828	2,002,426	2,414,568	22,547,890
Loss from operations	-2,601,828	-2,002,426	-2,414,568	-22,547,890
Other income (expense):	'	'	'	'
Interest income	7,248	1,690	10,696	221,100
Interest expense	-159,885	-24,042	-2,872	-365,827
Change in fair value of preferred stock purchase right	'	'	'	-188,587
Change in fair value of warrant liability	-82,000	7,250	5,500	-54,264
Grant income	'	'	'	244,000
Total other income (expense)	-234,637	-15,102	13,324	-143,578
Net loss and comprehensive loss	($2,836,465)	($2,017,528)	($2,401,244)	($22,691,468)
Net loss per common share, basic and diluted	($1.20)	($1.79)	($2.18)	'
Weighted-average shares used to compute basic and diluted net loss per share	2,368,006	1,124,000	1,102,625	'

Statements_of_Convertible_Pref

Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) (USD $)	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Deficit Accumulated During the Development Stage [Member]
		Series A Convertible Preferred Stock [Member]
Beginning Balance at Jan. 29, 2007	'	'	'	'	'
Beginning Balance, shares at Jan. 29, 2007	'	'	'	'	'
Issuance of restricted common stock for cash	4,580	'	92	4,488	'
Issuance of restricted common stock for cash, shares	'	'	916,000	'	'
Issuance of Series A convertible preferred stock	'	6,074,501	'	'	'
Issuance of Series A convertible preferred stock, shares	'	4,195,067	'	'	'
Initial fair value of preferred stock purchase rights issued in connection with Series A financing	'	-848,257	'	'	'
Estimated fair value of exercised purchase right	'	80,819	'	'	'
Issuance of common stock upon exercise of stock options	77,358	'	26	77,332	'
Issuance of common stock upon exercise of stock options, shares	'	'	266,750	'	'
Stock-based compensation expense	5,458	'	'	5,458	'
Net loss	-2,009,591	'	'	'	-2,009,591
Ending Balance at Dec. 31, 2007	-1,922,195	5,307,063	118	87,278	-2,009,591
Ending Balance, shares at Dec. 31, 2007	'	4,195,067	1,182,750	'	'
Issuance of Series A convertible preferred stock	'	5,998,145	'	'	'
Issuance of Series A convertible preferred stock, shares	'	4,000,000	'	'	'
Estimated fair value of exercised purchase right	'	956,025	'	'	'
Stock-based compensation expense	16,184	'	'	16,184	'
Net loss	-3,227,664	'	'	'	-3,227,664
Ending Balance at Dec. 31, 2008	-5,133,675	12,261,233	118	103,462	-5,237,255
Ending Balance, shares at Dec. 31, 2008	'	8,195,067	1,182,750	'	'
Stock-based compensation expense	17,803	'	'	17,803	'
Net loss	-5,159,638	'	'	'	-5,159,638
Ending Balance at Dec. 31, 2009	-10,275,510	12,261,233	118	121,265	-10,396,893
Beginning Balance, shares at Dec. 31, 2009	'	8,195,067	1,182,750	'	'
Issuance of Series A convertible preferred stock	'	5,963,933	'	'	'
Issuance of Series A convertible preferred stock, shares	'	4,000,001	'	'	'
Issuance of common stock upon exercise of stock options	24,000	'	6	23,994	'
Issuance of common stock upon exercise of stock options, shares	'	'	60,000	'	'
Stock-based compensation expense	15,056	'	'	15,056	'
Net loss	-5,039,338	'	'	'	-5,039,338
Ending Balance at Dec. 31, 2010	-15,275,792	18,225,166	124	160,315	-15,436,231
Ending Balance, shares at Dec. 31, 2010	'	12,195,068	1,242,750	'	'
Stock-based compensation expense	22,705	'	'	22,705	'
Net loss	-2,401,244	'	'	'	-2,401,244
Ending Balance at Dec. 31, 2011	-17,654,331	18,225,166	124	183,020	-17,837,475
Ending Balance, shares at Dec. 31, 2011	'	12,195,068	1,242,750	'	'
Stock-based compensation expense	12,505	'	'	12,505	'
Net loss	-2,017,528	'	'	'	-2,017,528
Ending Balance at Dec. 31, 2012	-19,659,354	18,225,166	124	195,525	-19,855,003
Beginning Balance, shares at Dec. 31, 2012	'	12,195,068	1,242,750	'	'
Issuance of common stock upon exercise of stock options, shares	'	'	'	'	'
Stock-based compensation expense	145,966	'	'	145,966	'
Conversion of shares of preferred stock to common stock	18,225,166	-18,225,166	244	18,224,922	'
Conversion of shares of preferred stock to common stock, shares	'	-12,195,068	2,439,002	'	'
Initial public offering of common stock	25,120,948	'	242	25,120,706	'
Initial public offering of common stock, shares	'	'	2,415,000	'	'
Reclassification of warrant liability	187,000	'	'	187,000	'
Net loss	-2,836,465	'	'	'	-2,836,465
Ending Balance at Dec. 31, 2013	$21,183,261	'	$610	$43,874,119	($22,691,468)
Ending Balance, shares at Dec. 31, 2013	'	'	6,096,752	'	'

Statements_of_Convertible_Pref1

Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) (USD $)	11 Months Ended	12 Months Ended
	Dec. 31, 2007	Dec. 31, 2013	Dec. 31, 2008	Dec. 31, 2010
				Preferred Stock [Member]
				Series A Convertible Preferred Stock [Member]
Issuance of restricted common stock, per share	$0.01	'	'	'
Issuance of Series A convertible preferred stock, per share	$1.50	'	$1.50	$1.50
Bridge notes	$250,000	'	'	'
Accrued interest	42,538	'	'	'
Issuance cost	218,037	'	1,855	36,069
Estimated fair value of exercised purchase right, per share	$0.04	'	'	'
Initial public offering of common stock, per share	'	$12	'	'
Offering costs	'	$3,859,052	'	'

Statements_of_Cash_Flows

Statements of Cash Flows (USD $)	12 Months Ended			83 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013
Operating activities	'	'	'	'
Net loss	($2,836,465)	($2,017,528)	($2,401,244)	($22,691,468)
Adjustments to reconcile net loss to net cash used in operating activities:	'	'	'	'
Stock-based compensation expense	145,966	12,505	22,705	235,677
Non-cash interest	23,261	4,042	2,426	129,327
Change in fair value of purchase right liability	'	'	'	188,587
Change in fair value of warrant liability	82,000	-7,250	-5,500	54,264
Deferred rent expense	6,830	'	'	6,830
Change in operating assets and liabilities:	'	'	'	'
Prepaid expenses and other assets	-234,262	39,459	76,353	-234,262
Other assets	-555,505	'	'	-555,505
Accounts payable and accrued expenses	327,905	218,909	-587,848	842,314
Net cash used in operating activities	-3,040,270	-1,749,863	-2,893,108	-22,024,236
Financing activities	'	'	'	'
Proceeds from convertible promissory note	'	'	'	250,000
Proceeds from bank line of credit and loan advances	2,000,000	1,000,000	'	5,500,000
Payment on bank line of credit	'	'	-277,779	-2,500,000
Proceeds from issuance of common stock, net	25,120,948	'	'	25,125,528
Proceeds from issuance of preferred stock and purchase rights, net	'	'	'	17,744,041
Proceeds from exercise of stock options	'	'	'	101,358
Net cash provided by (used in) financing activities	27,120,948	1,000,000	-277,779	46,220,927
Net increase (decrease) in cash and cash equivalents	24,080,678	-749,863	-3,170,887	24,196,691
Cash and cash equivalents at beginning of period	116,013	865,876	4,036,763	'
Cash and cash equivalents at end of period	24,196,691	116,013	865,876	24,196,691
Supplemental disclosures of cash flow information	'	'	'	'
Interest paid	128,875	20,000	1,346	228,751
Non-cash financing activities	'	'	'	'
Conversion of convertible promissory note and accrued interest to Series A Convertible Preferred Stock	'	'	'	292,538
Issuance of Series A Convertible Preferred Stock warrants	49,000	24,250	'	108,486
Conversion of Series A Convertible Preferred Stock to common stock at the initial public offering	$18,225,166	'	'	$18,225,166

Organization_and_Basis_of_Pres

Organization and Basis of Presentation	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Organization and Basis of Presentation	'
	1. Organization and Basis of Presentation
	Evoke Pharma, Inc. (the “Company”) was incorporated in the state of Delaware on January 29, 2007 (inception). The Company is a publicly-held specialty pharmaceutical company focused primarily on the development of drugs to treat gastroenterological disorders and disease.
	Since its inception, the Company has devoted substantially all of its efforts to product development, raising capital and building infrastructure, and has not realized revenues from its planned principal operations. Accordingly, the Company is considered to be in the development stage.
	As reflected in the accompanying financial statements, the Company has a limited operating history and the sales and income potential of the Company’s business are unproven. The Company has experienced net losses since its inception and, as of December 31, 2013 and 2012, had an accumulated deficit of $22,691,468 and $19,855,003, respectively. The Company had a working capital (deficit) of $22,146,047 and $(454,396) as of December 31, 2013 and 2012, respectively.
	The Company expects to continue to incur net losses for at least the next several years. Over that period, the Company will need to raise additional debt or equity financing to fund its development. If the Company is not able to secure adequate additional funding, the Company may be forced to make reductions in spending, extend payment terms with suppliers, and/or suspend or curtail planned programs. Any of these actions could materially harm the Company’s business, results of operations, financial condition and future prospects.
	On June 13, 2013, the Company’s board of directors approved an amendment to the restated certificate of incorporation to effect a one-for-five reverse stock split of the Company’s common stock (the “Reverse Stock Split”). The amendment effecting the Reverse Stock Split was approved by the stockholders on August 29, 2013. The par value and the authorized shares of the common and convertible preferred stock were not adjusted as a result of the Reverse Stock Split. All issued and outstanding common stock and the conversion ratio of the convertible preferred stock have been retroactively adjusted to reflect this Reverse Stock Split for all periods presented. The Reverse Stock Split was effected on August 30, 2013.
	Initial Public Offering and Related Transactions
	On September 30, 2013, the Company completed its Initial Public Offering (“IPO”) whereby it sold 2,100,000 shares of common stock at a price of $12.00 per share. On October 8, 2013, the underwriters for the Company’s IPO purchased the over-allotment option for an additional 315,000 shares of the Company’s common stock at $12.00 per share. Net proceeds from the IPO, including the exercise of the over-allotment option, were determined as follows:
	Gross proceeds (including over-allotment)		$	28,980,000
	Underwriting discounts and commissions and non-accountable expense allowance			(2,344,875	)
	Total offering costs (excluding value of warrants granted to underwriter of $470,000)			(1,514,177	)
	Net proceeds		$	25,120,948
	Additionally, upon the closing of the IPO, certain transactions occurred based on a successful completion of the IPO:
		•		the conversion of all outstanding shares of convertible preferred stock into 2,439,002 shares of the Company’s common stock;
		•		retention payments in the amount of $355,000 became payable to the Company’s executive officers. Such amount was recorded as expense on a straight-line basis from May 22, 2013 (the date of the retention agreements entered into with the executive officers) through December 24, 2013, the date at which the final payment was due based on continued employment. Since the terms of the payment required the occurrence of either a change in control of the Company, or an equity financing, neither of which were considered probable to occur until they happen, a catch-up expense of $202,857 was recorded at the time of the Company’s IPO. The executive officers remained with the Company through December 24, 2013 and received the full retention payment;
		•		the issuance of warrants to purchase 84,000 shares of the Company’s common stock to the representative of the underwriters of the Company’s IPO and certain of its affiliates. The warrants will become exercisable at a price of $21.00 per share beginning on September 24, 2014 and will expire on September 24, 2018. The $470,000 initial fair value of the warrants was determined using the Black-Scholes option pricing model and recorded as a cost of the Company’s IPO and charged to additional paid-in capital;
	The fair value of the issued warrants was estimated using the Black-Scholes option pricing model with the following assumptions:
	Assumed risk-free interest rate			1.44	%
	Assumed volatility			71	%
	Expected warrant life			5 Years
	Expected dividend yield			0	%
		•		the conversion of warrants to purchase 110,000 shares of convertible preferred stock into warrants to purchase 22,000 shares of the Company’s common stock, and the final remeasurement of fair value and reclassification of the $187,000 warrant liability to additional paid-in capital; and
		•		the filing of an amended and restated certificate of incorporation to authorize 50,000,000 shares of common stock and 5,000,000 shares of undesignated preferred stock.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Summary of Significant Accounting Policies	'
	2. Summary of Significant Accounting Policies
	Use of Estimates
	The accompanying financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”). The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Actual results could differ from those estimates.
	Segment Reporting
	Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. The Company views its operations and manages its business in one operating segment operating in the United States.
	Cash and Cash Equivalents
	The Company considers all highly liquid investments with an original maturity of three months or less from the date of purchase to be cash equivalents. Cash and cash equivalents include cash in readily available checking and savings accounts.
	Fair Value of Financial Instruments
	The carrying amounts of accounts payable and accrued expenses are considered to be representative of their respective fair values because of the short-term nature of those instruments. Based on the borrowing rates currently available to the Company for loans with similar terms, the Company believes that the fair value of long-term debt approximates its carrying value. The carrying amount of the warrant liability represents fair value.
	Concentrations of Risk
	Financial instruments that potentially subject the Company to significant credit risk consist primarily of cash and cash equivalents. The Company maintains deposits in a federally insured financial institution in excess of federally insured limits. The Company has established guidelines designed to maintain safety and liquidity, has not experienced any losses in such accounts and believes the exposure to significant risk to the cash balance is minimal.
	In addition, the Company relies on third-party manufacturers for the production of its drug candidate. If the third-party manufacturers are unable to continue manufacturing the Company’s drug candidate, or if the Company loses one of its sole source suppliers used in its manufacturing processes, the Company may not be able to meet clinical trial supply demand for its product candidate and the development of the product candidate could be materially and adversely affected.
	Preferred Stock Warrant Liability
	Warrants for shares that are puttable and warrants for shares that are contingently redeemable are classified as liabilities on the accompanying balance sheets and carried at their estimated fair value. At the end of each reporting period, any changes in fair value are recorded as a component of other income (expense). At the completion of the IPO, the Company adjusted the carrying value of the warrants and reclassified the liability to additional paid-in capital.
	Stock-Based Compensation
	Stock-based compensation expense is recorded at the estimated fair value of the award as of the grant date and is recognized as expense on a straight-line basis over the employee’s requisite service period, which is generally the vesting period of the award. Stock-based compensation expense is based on awards ultimately expected to vest, and therefore, the recorded expense includes an estimate of future forfeitures. Forfeitures are to be estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates.
	Prior to the IPO, the Company granted stock options to purchase common stock to employees with exercise prices equal to the value of the underlying stock, as determined by the board of directors on the date the equity award was granted. The board of directors determined the fair value of the underlying common stock by considering a number of factors, including historical and projected financial results, the risks the Company faced at the time, the preferences of the Company’s preferred stockholders and the lack of liquidity of the Company’s common stock. Subsequent to the IPO, the exercise price of the stock options granted to employees and members of the board of directors of the Company was determined by the Company’s closing market price on the date the stock options were granted.
	The fair value of each option award is estimated on the date of grant using the Black-Scholes valuation model using the appropriate risk-free interest rate, expected term and volatility assumptions. The expected life of options was calculated using the simplified method, which calculates the life as the average of the contractual term of the stock option and the vesting period of the option. Due to the Company’s limited historical data as a public company, the estimated volatility is calculated based upon the historical volatility of the Company and comparable companies whose share prices are publicly available for a sufficient period of time. The risk-free interest rate is based upon U.S. Treasury securities with remaining terms similar to the expected term of the stock award being valued. The Company granted 501,500 options in 2013 and no options in 2012.
	Research and Development Expenses
	Research and development costs are expensed as incurred and primarily include compensation and related benefits, stock-based compensation expense, costs paid to third-party contractors to perform research, conduct clinical trials and develop drug materials and delivery devices. The Company expenses costs relating to the purchase and production of pre-approval inventories as research and development expense in the period incurred until FDA approval is received.
	The Company bases its expense accruals related to clinical studies on estimates of the services received and efforts expended pursuant to contracts with multiple research institutions and clinical research organizations , or CROs, that conduct and manage clinical studies on our behalf. The financial terms of these agreements vary from contract to contract and may result in uneven payment flows. Payments under some of these contracts depend on factors, such as the successful enrollment of patients, site initiation and the completion of clinical study milestones. Service providers invoice us monthly in arrears for services performed. In accruing service fees, the Company estimates the time period over which services will be performed and the level of effort to be expended in each period. If the Company does not identify costs that have begun to be incurred, or if the Company underestimates or overestimates the level of services performed or the costs of these services, actual expenses could differ from estimates. To date, the Company has not experienced significant changes in estimates of accrued research and development expenses after a reporting period. However, due to the nature of estimates, no assurance can be made that changes to the estimates will not be made in the future as the Company becomes aware of additional information about the status or conduct of clinical studies and other research activities.
	We do not own or operate manufacturing facilities for the production of EVK-001, nor do we have plans to develop our own manufacturing operations in the foreseeable future. We currently depend on third-party contract manufacturers for all of our required raw materials, drug substance and finished product for our preclinical research and clinical trials. We do not have any current contractual relationships for the manufacture of commercial supplies of EVK-001. If EVK-001 is approved by any regulatory agency, we intend to enter into agreements with third-party contract manufacturers for the commercial production at that time. We currently utilize a third-party consultant, which we engage on an as-needed, hourly basis, to manage our manufacturing contractors.
	Income Taxes
	The Company accounts for income taxes in accordance with ASC 740, Income Taxes. Under ASC 740, deferred tax assets and liabilities reflect the future tax consequences of the differences between the financial reporting and tax basis of assets and liabilities using current enacted tax rates. The Company provides a valuation allowance against net deferred tax assets unless, based upon the available evidence, it is more likely than not that the deferred tax assets will be realized.
	The Company’s policy related to accounting for uncertainty in income taxes prescribes a recognition threshold and measurement attributed criteria for the financial statement recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more likely than not to be sustained upon examination by taxing authorities.
	Comprehensive Income (Loss)
	ASC 220, Comprehensive Income, defines comprehensive income (loss) as a change in equity during a period from transactions and other events and circumstances from non-owner sources. Net loss and comprehensive loss were the same for all periods presented.
	Net Loss Per Share
	Basic net loss per share is calculated by dividing the net loss by the weighted-average number of common shares outstanding for the period, without consideration for common stock equivalents and adjusted for the weighted-average number of common shares outstanding that are subject to repurchase. The Company has excluded 103,750, 118,750 and 140,125 weighted-average shares subject to repurchase from the weighted-average number of common shares outstanding for the year ended December 31, 2013, 2012 and 2011, respectively. Diluted net loss per share is calculated by dividing the net loss by the weighted-average number of common share equivalents outstanding for the period determined using the treasury-stock method. Dilutive common stock equivalents are comprised of convertible preferred stock, warrants for the purchase of convertible preferred stock, warrants for the purchase of common stock, and options outstanding under the Company’s equity incentive plans. For the periods presented, there is no difference in the number of shares used to calculate basic and diluted shares outstanding due to the Company’s net loss position.
	The following table summarizes the weighted-average anti-dilutive securities excluded from the calculation of diluted net loss per share (in common equivalent shares):
		Year Ended December 31,
		2013		2012		2011
	Convertible preferred stock outstanding		—		2,439,002		2,439,002
	Warrants for convertible preferred stock		—		14,000		10,000
	Warrants for common stock		106,000		—		—
	Common stock options		624,750		123,250		123,250
			730,750		2,576,252		2,572,252
	Recent Accounting Pronouncements
	In February 2013, the Financial Accounting Standards Board issued an accounting standard update to require reclassification adjustments from other comprehensive income to be presented either in the financial statements or in the notes to the financial statements. This accounting standard became effective for the Company beginning in the first quarter of 2013, and its adoption did not have any impact on the Company’s financial statements.
	In July 2013, the FASB issued Accounting Standards Update No. 2013-11, presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists (“ASU 2013-11”). The guidance is effective prospectively for fiscal years, and interim periods within those years, beginning after December 15, 2013, with an option for early adoption. The Company intends to adopt this guidance during the first quarter of 2014, and does not believe the adoption of this standard will have a material impact on the Company’s consolidated financial statements.

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Fair Value Measurements	'
	3. Fair Value Measurements
	The following tables present information about the Company’s financial liabilities measured at fair value on a recurring basis as of December 31, 2013 and 2012 and indicate the fair value hierarchy of the valuation techniques utilized by the Company to determine such fair value. The Company had no financial liabilities as of December 31, 2013. As a basis for categorizing inputs, the Company uses a three-tier fair value hierarchy, which prioritizes the inputs used to measure fair value from market based assumptions to entity specific assumptions:
	Level 1: Observable inputs such as quoted prices in active markets;
	Level 2: Inputs, other than the quoted prices in active markets, that are observable either directly or indirectly; and
	Level 3: Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions.
	The Company’s Level 3 financial liabilities consisted of warrant liabilities related to warrants to purchase preferred stock. All warrants were measured at fair value utilizing the Black-Scholes option pricing model.
	The fair value of the outstanding preferred stock warrants at December 31, 2012 was estimated using the Black-Scholes option pricing model with the following assumptions:
		December 31, 2012
	Assumed risk-free-interest rate		0.25% — 1.78%
	Assumed volatility		80%
	Expected warrant life		2.08 — 9.50 years
	Expected dividend yield		0.00%
	Liabilities measured at fair value on a recurring basis as of December 31, 2012 are as follows:
					Fair Value Measurements
					at Reporting Date Using
		Balance as of			Quoted Prices		Significant		Significant
		December 31,			in Active		Other		Unobservable
		2012			Markets for		Observable		Inputs
					Identical		Inputs		(Level 3)
					Assets		(Level 2)
					(Level 1)
	Liabilities:
	Preferred stock warrant liability	$	56,000		$	—	$	—	$	56,000
	Total liabilities		56,000		$	—	$	—	$	56,000
	The following table is a reconciliation of all the Company’s liabilities measured using significant unobservable inputs (Level 3) for the years ended December 31, 2013 and 2012:
		Warrant
		Liability
	Fair value measurement at December 31, 2011	$	39,000
	Warrants issued in connection with loan and security agreement		24,250
	Change in fair value of warrant liability		(7,250	)
	Fair value measurement at December 31, 2012		56,000
	Warrants issues in connection with loan and security agreement		49,000
	Change in fair value of warrant liability		82,000
	Reclassification to additional paid-in capital at initial public offering		(187,000	)
	Fair value measurement at December 31, 2013	$	—

Debt

Debt	12 Months Ended
	Dec. 31, 2013
Debt Disclosure [Abstract]	'
Debt	'
	4. Debt
	In June 2012, the Company entered into a $3.0 million loan and security agreement collateralized by the Company’s personal property. Interest on advances under the agreement is at a fixed interest rate equal to 4.50%. The loan and security agreement contains only non-financial covenants. Advances under the loan and security agreement have an interest-only period through December 31, 2013 and a 24-month payback period commences in January 2014. The Company was advanced $1 million and $2 million in July 2012 and January 2013, respectively. As such, as of December 31, 2013 and 2012, the Company had $0 and $2.0 million, respectively, in available credit under the loan and security agreement.
	In connection with the loan and security agreement, a warrant was issued for shares of Series A Convertible Preferred Stock that is exercisable in whole, or in part, at any time until the expiration date of June 1, 2022. During July 2012, the Company drew down $1.0 million under the loan and security agreement and the warrant became exercisable for 4,000 shares of Series A Convertible Preferred Stock at an exercise price of $7.50 per share. During January 2013, the Company drew down the remaining $2.0 million under the loan and security agreement and the warrant became exercisable for an additional 8,000 shares of Series A Convertible Preferred Stock at an exercise price of $7.50 per share.
	The initial $24,250 fair value of the 4,000 warrant shares earned in July 2012 and the initial $49,000 fair value of the 8,000 warrant shares earned in January 2013 were recorded as a debt discount and are amortized to interest expense over the term of the loan using the effective interest method. As of December 31, 2013 and 2012, the Company had unamortized debt discount of $45,947 and $20,208, respectively, related to the initial fair value of the warrants.
	The initial fair value of warrants earned in 2013 and 2012 was estimated using the Black-Scholes option pricing model with the following assumptions:
		January 2013			July 2012
	Assumed risk-free interest rate		1.86	%		1.43	%
	Assumed volatility		80	%		80	%
	Expected warrant life		9.5 Years			10 Years
	Expected dividend yield		0	%		0	%
	The aggregate advances under the loan and security agreement and unamortized discount as of December 31, 2013 and 2012 are as follows:
		December 31,			December 31,
		2013			2012
	Aggregate advances under loan and security agreement	$	3,000,000		$	1,000,000
	Less unamortized discount		(45,947	)		(20,208	)
	Long-term debt, net of debt discount		2,954,053			979,792
	Current portion of unamortized discount		23,260			—
	Current portion of long-term debt		(1,465,852	)		—
	Long-term debt, net of current portion	$	1,511,461		$	979,792
	Maturities of long-term debt as of December 31, 2013, are as follows:
			2014		$	1,572,285
			2015			1,572,285
	Total minimum payments					3,144,570
	Less amount representing interest					(144,570	)
	Total outstanding debt					3,000,000
	Less current portion					(1,465,852	)
	Long-term portion				$	1,534,148
	Total interest incurred under the loan and security agreement for the years ended December 31, 2013 and 2012 (excluding amortization of debt discount) was $136,625 and $20,000, respectively.

Commitments

Commitments	12 Months Ended
	Dec. 31, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Commitments	'
	5. Commitments
	In November 2013, the Company entered into an operating lease for office space in Solana Beach, California. The lease commenced on December 1, 2013 and will expire on December 31, 2015. Although rent payments did not commence until December 2013, the Company took possession of the facility in November 2013 to move into the facility. The lease contains annual rent increases and the Company received lease incentives in the form of rent abatements and a moving allowance.
	The Company recognizes minimum rent payments, escalation clauses and lease incentives on a straight-line basis over the term of its operating lease. Prior to entering into the facility lease, the Company temporarily leased office space on a month-to-month basis and recognized the expense as incurred.
	Rent expense for 2013, 2012, 2011 and the period from January 29, 2007 (inception) to December 31, 2013 was $8,886, $5,000, $12,000, and $57,686, respectively. The difference between the minimum lease payments and the straight-line amount is accounted for as deferred rent. Deferred rent expense at December 31, 2013 and 2012 was $6,830 and $0, respectively. We also pay pass through costs and utility costs, which are expensed as incurred.
	As of December 31, 2013, future minimum lease payments for our operating lease are as follows:
	2014	$	75,603
	2015		93,399
	Total	$	169,002

Acquisition_of_Technology

Acquisition of Technology	12 Months Ended
	Dec. 31, 2013
Business Combinations [Abstract]	'
Acquisition of Technology	'
	6. Acquisition of Technology
	In June 2007, the Company purchased from Questcor Pharmaceuticals, Inc. (“Questcor”) all rights and patents to a development program for the Company’s EVK-001 product candidate, for an upfront payment of $650,000 which was expensed as in-process research and development. In addition to the upfront payment, the Company will be required to make additional milestone payments totaling up to $52,000,000. These milestones include up to $5,000,000 in payments if EVK-001 achieves the following development targets:
		•	$500,000 upon the initiation of the first patient dosing in the Company’s planned Phase 3 clinical trial for EVK-001;
		•	$1,500,000 upon the U.S. Food and Drug Administration’s (the “FDA”) acceptance for review of a new drug application for EVK-001; and
		•	$3,000,000 upon the FDA’s approval of EVK-001.
	The remaining $47,000,000 in milestone payments depend on EVK-001’s commercial success and will only apply if EVK-001 receives regulatory approval. In addition, the Company will be required to pay to Questcor a low single digit royalty on net sales of EVK-001. The Company’s obligation to pay such royalties will terminate upon the expiration of the last patent right covering EVK-001, which is expected to occur in 2030.

Convertible_Preferred_Stock_Co

Convertible Preferred Stock, Common Stock and Stockholders' Equity (Deficit)	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Convertible Preferred Stock, Common Stock and Stockholders' Equity (Deficit)	'
	7. Convertible Preferred Stock, Common Stock and Stockholders’ Equity (Deficit)
	Convertible Preferred Stock
	The Company’s convertible preferred stock has been classified as temporary equity in the accompanying balance sheets instead of in stockholders’ equity (deficit) in accordance with authoritative guidance for the classification and measurement of potentially redeemable securities. Upon certain change in control events that are outside of the Company’s control, including liquidation, sale or transfer of control of the Company, holders of the convertible preferred stock were able to cause its redemption.
	During June and October 2007, the Company sold an aggregate of 4,000,000 shares of Series A Convertible Preferred Stock at $1.50 per share for gross proceeds of $6,000,000 in cash. In addition, $250,000 in convertible promissory notes issued in an earlier bridge financing and $42,538 in accrued interest thereon converted into 195,067 shares of Series A Convertible Preferred Stock. In connection with the Series A Convertible Preferred Stock issuance, $848,257 of the proceeds were allocated to the preferred stock purchase right liability, and the Company incurred $218,037 of offering costs.
	As part of the October 2007 Series A Convertible Preferred Stock transaction, the preferred stock purchase right liability for the second closing was revalued with the $4,132 increase in fair value recorded as other expense on the statement of operations and the then fair value of $80,819 was reclassified to Series A Convertible Preferred Stock. At December 31, 2007, the preferred stock purchase right liability for the third closing was revalued with the $68,955 increase in fair value recorded as other expense on the statement of operations.
	During November 2008, the Company sold an additional 4,000,000 shares of Series A Convertible Preferred Stock for gross proceeds of $6,000,000 in cash. In connection with this financing, the Company incurred $1,855 of offering costs. As part of the Series A Convertible Preferred Stock transaction, the preferred stock purchase right liability for the third closing was revalued with the $115,500 increase in fair value recorded as other expense on the statement of operations and the then fair value of $956,025 was reclassified to Series A Convertible Preferred Stock.
	During June 2010, the Company sold an additional 4,000,001 shares of Series A Convertible Preferred Stock for gross proceeds of $6,000,002 in cash. In connection with this financing, the Company incurred $36,069 of offering costs.
	The holders of the Series A Convertible Preferred Stock were entitled to receive noncumulative dividends at a rate of $0.12 per share per annum. The preferred stock dividends were payable when and if declared by the board of directors. As of December 31, 2012 and June 30, 2013, the board of directors had not declared any dividends. The Series A Convertible Preferred Stock dividends were payable in preference and in priority to any dividends on common stock. At the time of the conversion of the Series A Convertible Preferred Stock, no dividends had been declared.
	The holders of the Series A Convertible Preferred Stock were entitled to receive liquidation preferences at the rate of $1.50 per share, plus all declared and unpaid dividends. Liquidation payments to the holders of Series A Convertible Preferred Stock had priority and were made in preference to any payments to the holders of common stock.
	The shares of Series A Convertible Preferred Stock were convertible into one share of common stock for each five shares of preferred stock, at the option of the holder, subject to certain anti-dilutive adjustments. Each share of Series A Convertible Preferred Stock was automatically converted into common stock immediately upon the earlier of (i) the Company’s sale of its common stock in a firm commitment underwritten public offering pursuant to a registration statement under the Securities Act of 1933, as amended, in which the per share price is at least $22.50 (as adjusted), and the gross cash proceeds are at least $25,000,000 or (ii) the date specified by written consent or agreement of the holders of not less than 66.66% of the then outstanding shares of Series A Convertible Preferred Stock.
	The holders of Series A Convertible Preferred Stock were entitled to one vote for each share of common stock into which such Series A Convertible Preferred Stock could then be converted; and with respect to such vote, such holder had full voting rights and powers equal to the voting rights and powers of the holders of common stock.
	The holders of the Series A Convertible Preferred Stock with greater than 250,000 shares were entitled to elect one member each to the Company’s board of directors.
	As of December 31, 2013, there were no shares of Series A Convertible Preferred Stock issued or outstanding as all shares, totaling 2,439,002 of Series A Convertible Preferred Stock, converted to 2,439,002 shares of common stock immediately prior to the completion of the IPO.
	Under the Company’s amended and restated certificate of incorporation as of December 31, 2013, the Company is authorized to issue 5,000,000 shares of preferred stock with a $0.0001 par value.
	Common Stock
	As of December 31, 2013, there were 6,096,752 shares of common stock outstanding. Each share of common stock is entitled to one vote. The holders of the common stock are also entitled to receive dividends whenever funds are legally available and when declared by the board of directors of the Company. To date, no dividends have been declared.
	Stock Options
	The Company adopted the 2007 Equity Incentive Plan (the “2007 Plan”) in May 2007 under which 450,000 shares of common stock were reserved for issuance to employees, nonemployee directors and consultants of the Company. As of December 31, 2012 no options were available for future grant under this plan. In August 2013, the Company adopted the 2013 Equity Incentive Award Plan (the “2013 Plan”) as a successor to the 2007 Plan.
	Under the 2013 Plan, the Company may grant stock options, stock appreciation rights, restricted stock, restricted stock units and other awards to individuals who are then employees, officers, non-employee directors or consultants of the Company. A total of 510,000 shares of common stock were initially reserved for issuance under the 2013 Plan. In addition, the number of shares of common stock available for issuance under the 2013 Plan will be annually increased on the first day of each fiscal year during the term of the 2013 Plan, beginning with the 2014 fiscal year, by an amount equal to the least of: (i) 300,000 shares; (ii) four percent of the outstanding shares of common stock as of the last day of the immediately preceding fiscal year; or (iii) such other amount as the Company’s board of directors may determine. As of December 31, 2013, 8,500 options remain available for future grant under the 2013 Plan.
	Options granted under the 2007 Plan and 2013 Plan have terms ranging from seven to ten years from the date of grant and generally vest over a three to four year period. The exercise price of all options granted during the years ended December 31, 2013, 2012 and 2011 was equal to the market value per share of the Company’s common stock on the date of grant.
	A summary of the Company’s stock option activity under the 2007 Plan and 2013 Plan is as follows:
			Shares				Weighted			Weighted		Aggregate
							Average			Average		Intrinsic
							Exercise			Remaining		Value
							Price			Contractual
										Term
										(Years)
	Outstanding at December 31, 2012			123,250			$	0.4			7.84	$	578
	Granted			501,500			$	9.39			9.88		—
	Exercised			—				—			—		—
	Canceled/Forfeited			—				—			—		—
	Outstanding at December 31, 2013			624,750			$	7.61			8.41	$	869,490
	Exercisable at December 31, 2013 (1)			90,540			$	0.39			5.01	$	638,881
	Vested or expected to vest at December 31, 2013			624,750			$	7.61			8.41	$	869,490
	-1	Includes awards with early exercise provisions that permit optionee to exercise unvested options.
	The intrinsic values above represent the aggregate value of the total pre-tax intrinsic value based upon a common stock price of $7.45 and $0.40 at December 31, 2013 and 2012, respectively, and the contractual exercise prices.
	The 2007 Plan permits the early exercise of options, but the Company has the option to repurchase any unvested shares at the original purchase price (the exercise price paid by the Purchaser) upon any voluntary or involuntary termination (“Repurchase Option”). The shares of common stock issued from the exercise of stock options are restricted and vest over time or on the achievement of certain milestones. Any unvested shares immediately vest in the event of termination for reasons other than cause, and vesting accelerates in the event of a merger, sale, or other change in control of the Company. Of the total 326,750 stock options exercised, 230,500 and 215,500 were vested as of December 31, 2013 and 2012, respectively.
	The total intrinsic value of stock options exercised was $0 for the years ended December 31, 2013, 2012 and 2011, respectively, as there were no options exercised during these years.
	Stock-Based Compensation
	The estimated fair value of each option award granted was determined on the date of grant using the Black-Scholes option-pricing valuation model with the following weighted-average assumptions for options grants during the three years ended December 31, 2013:
			Year Ended December 31,
			2013		2012				2011
	Stock Options
	Risk free interest rate		1.75% - 1.8%			—			2.33%
	Expected option term		6.0 years			—			5.0 years
	Expected volatility of common stock		70.8% - 79.4%			—			80.00%
	Expected dividend yield		—%			—			—%
	The risk-free interest rate assumption was based on the yield of an applicable rate for U.S. Treasury instruments with maturities similar to those of the expected term of the award being valued. The assumed dividend yield was based on the Company never paying cash dividends and having no expectation of paying cash dividends in the foreseeable future. The weighted average expected term of options was calculated using the simplified method as prescribed by accounting guidance for stock-based compensation. This decision was based on the lack of relevant historical data due to the Company’s limited historical experience. In addition, due to the Company’s limited historical data, the estimated volatility was calculated based upon the Company’s historical volatility, supplemented with historical volatility of comparable companies in the biotechnology industry whose share prices are publicly available for a sufficient period of time.
	The weighted average grant date fair value per share of employee stock options granted during the years ended December 31, 2013, 2012 and 2011 was $6.33, $0 and $0.05, respectively.
	The Company recognized non-cash stock-based compensation expense to employees and directors in its research and development and its general and administrative functions as follows:
			Year Ended December 31,									Period from
												January 29,
												2007
												(Inception) to
												December 31,
			2013				2012			2011		2013
	Research and development		$	39,638			$	10,004		$	15,360	$	93,435
	General and administrative			106,328				2,501			7,345		142,243
	Total stock-based compensation expense		$	145,966			$	12,505		$	22,705	$	235,678
	As of December 31, 2013 and 2012, there was approximately $3,055,000 and $26,000, respectively, of unrecognized compensation costs related to outstanding employee and board of director options, which is expected to be recognized over a weighted average period of 1.84 and 2.0 years, respectively.
	Employee Stock Purchase Plan
	On June 13, 2013, the Company’s board of directors adopted the Employee Stock Purchase Plan (the “ESPP”), and the Company’s stockholders approved the ESPP on August 29, 2013. The ESPP became effective on the day prior to the effectiveness of the IPO. The ESPP permits participants to purchase common stock through payroll deductions of up to 20% of their eligible compensation. A total of 30,000 shares of common stock will initially be reserved for issuance under the ESPP. In addition, the number of shares of common stock available for issuance under the ESPP will be annually increased on the first day of each fiscal year during the term of the ESPP, beginning with the 2014 fiscal year, by an amount equal to the least of: (i) 30,000 shares; (ii) one percent of the outstanding shares of common stock as of the last day of the immediately preceding fiscal year; or (iii) such other amount as the Company’s board of directors may determine. No shares of common stock have been issues under the ESPP.
	Common Stock Reserved for Future Issuance
Common stock reserved for future issuance consists of the following at December 31, 2013 and 2012:
		December 31,
		2013				2012
Conversion of preferred stock			—				2,439,002
Stock options issued and outstanding			624,750				123,250
Authorized for future option grants			8,500				—
Warrants for convertible preferred stock			—				14,000
Warrants for common stock			106,000				—
Authorized for Employee Stock Purchase Plan			330,000				—
Total common stock reserved for future issuance			1,069,250				2,576,252

Employee_Benefit_Plan

Employee Benefit Plan	12 Months Ended
	Dec. 31, 2013
Postemployment Benefits [Abstract]	'
Employee Benefit Plan	'
	8. Employee Benefit Plan
	The Company has established a defined contribution 401(k) plan (the Plan) for all employees who are at least 21 years of age. Employees are eligible to participate in the Plan beginning one year following the date of employment. Under the terms of the Plan, employees may make voluntary contributions as a percentage of compensation. The Company’s contributions to the Plan are discretionary, and no contributions have been made by the Company to date.

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	9. Income Taxes
	On January 1, 2009, the Company adopted authoritative guidance relating to the accounting for uncertainty in income taxes. The guidance clarified the recognition threshold and measurement attributes for financial statement disclosure of tax positions taken, or expected to be taken, on a tax return. The impact of an uncertain income tax position on the income tax return must be recognized at the largest amount that is more likely than not to be sustained upon audit by the relevant taxing authority. An uncertain tax position will not be recognized if it has a less than 50% likelihood of being sustained. On the date of adoption, there were no unrecognized tax benefits. Further, there is no unrecognized tax benefit included in the Company’s balance sheets at December 31, 2013 and 2012 that would, if recognized, affect the Company’s effective tax rate.
	The Company’s policy is to recognize interest and/or penalties related to income tax matters in income tax expense. The Company had no accrual for interest and penalties on the balance sheets at December 31, 2013 and 2012. The Company is subject to taxation in the United States and state jurisdictions, and as of December 31, 2013, the Company’s tax years beginning 2007 to date are subject to examination by taxing authorities. The Company does not foresee material changes to its gross uncertain income tax position liability within the next twelve months.
	A reconciliation of the federal statutory income tax rate and the effective income tax rate is as follows for the years ended December 31:
		December 31,
		2013			2012			2011
		(%)			(%)			(%)
	Federal statutory rate		34			34			34
	Change in valuation allowance		(2.5	)		(4.9	)		(0.2	)
	State income taxes, net of federal effect		5.8			5.8			5.8
	Research and development credits		4.3			1.5			4.2
	Removal of net operating loss and other credits		(39.5	)		(36.4	)		(43.9	)
	Other		(2.1	)		(0.0	)		0.1
	Effective income tax rate		0			0			0
	Pursuant to Internal Revenue Code (IRC) Sections 382 and 383, annual use of the Company’s net operating loss and research and development credit carryforwards may be limited in the event a cumulative change in ownership of more than 50% occurs within a three-year period. The Company has not completed an IRC Section 382/383 analysis regarding the limitation of net operating loss and research and development credit carryforwards. Until this analysis has been completed, the Company has removed the deferred tax assets for net operating losses of approximately $8.4 million and a research and development credit of approximately $931,000 generated through December 31, 2013 from its deferred tax asset schedule, and has recorded a corresponding decrease to its valuation allowance. When this analysis is finalized, the Company plans to update its unrecognized tax benefits accordingly. The Company does not expect this analysis to be completed within the next twelve months and, as a result, the Company does not expect that the unrecognized tax benefits will change within twelve months of this reporting date. Due to the existence of the valuation allowance, future changes in the Company’s unrecognized tax benefits will not impact the Company’s effective tax rate.
	Significant components of the Company’s deferred tax assets at December 31, 2013 and 2012 are as follows:
		December 31,
		2013			2012
	Deferred tax assets:
	Acquired technology	$	147,000		$	164,000
	Other, net		290,000			203,000
	Total deferred tax assets		437,000			367,000
	Less valuation allowance		(437,000	)		(367,000	)
	Net deferred tax assets	$	—		$	—
	At December 31, 2013, the Company has federal and state net operating loss carryforwards of approximately $21.2 million and $20.7 million, respectively. The federal and state loss carryforwards begin to expire in 2027 and 2017, respectively, unless previously utilized. The Company also has federal and state research tax credit carryforwards of approximately $627,000 and $459,000, respectively. The federal research credit carryforwards will begin expiring in 2027 unless previously utilized. The state research credit will carry forward indefinitely.

Subsequent_Events

Subsequent Events	12 Months Ended
	Dec. 31, 2013
Subsequent Events [Abstract]	'
Subsequent Events	'
	10. Subsequent Events
	For the purposes of the financial statements as of December 31, 2013 and the year then ended, the Company has evaluated subsequent events through March 25, 2014, the date the audited annual financial statements were issued. The Company has concluded that no subsequent event has occurred that requires disclosure.

Summarized_Quarterly_Data

Summarized Quarterly Data	12 Months Ended
	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
Summarized Quarterly Data	'
	11. Summarized Quarterly Data (Unaudited)
	The following financial information reflects all adjustments, which include only normal recurring adjustments, which are, in the opinion of management, necessary for a fair statement of the consolidated financial results of the interim periods. Summarized quarterly data for the years ended December 31, 2013 and 2012 are as follows:
			For the Quarters Ended
			March 31,			June 30,			September 30,			December 31,
	2013
	Research and development expense		$	110,981		$	130,846		$	78,731		$	636,423
	General and administrative expense			221,049			72,578			406,862			944,359
	Net loss			(493,992	)		(239,871	)		(485,904	)		(1,616,698	)
	Net loss per share, basic and diluted (1)			(0.44	)		(0.21	)		(0.41	)		(0.27	)
	Weighted average shares outstanding, basic and diluted			1,133,375			1,137,125			1,190,212			5,971,236
	2012
	Research and development expense		$	297,285		$	213,010		$	337,003		$	318,347
	General and administrative expense			205,137			147,328			140,746			343,570
	Net loss			(500,158	)		(358,666	)		(486,254	)		(672,450	)
	Net loss per share, basic and diluted (1)			(0.45	)		(0.32	)		(0.43	)		(0.60	)
	Weighted average shares outstanding, basic and diluted			1,118,375			1,122,125			1,125,875			1,129,625
	-1	Net loss per share is computed independently for each of the quarters presented. Therefore, the sum of the quarterly per-share calculations will not necessarily equal the annual per share calculation.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Use of Estimates	'
	Use of Estimates
	The accompanying financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”). The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Actual results could differ from those estimates.
Segment Reporting	'
	Segment Reporting
	Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. The Company views its operations and manages its business in one operating segment operating in the United States.
Cash and Cash Equivalents	'
	Cash and Cash Equivalents
	The Company considers all highly liquid investments with an original maturity of three months or less from the date of purchase to be cash equivalents. Cash and cash equivalents include cash in readily available checking and savings accounts.
Fair Value of Financial Instruments	'
	Fair Value of Financial Instruments
	The carrying amounts of accounts payable and accrued expenses are considered to be representative of their respective fair values because of the short-term nature of those instruments. Based on the borrowing rates currently available to the Company for loans with similar terms, the Company believes that the fair value of long-term debt approximates its carrying value. The carrying amount of the warrant liability represents fair value.
Concentrations of Risk	'
	Concentrations of Risk
	Financial instruments that potentially subject the Company to significant credit risk consist primarily of cash and cash equivalents. The Company maintains deposits in a federally insured financial institution in excess of federally insured limits. The Company has established guidelines designed to maintain safety and liquidity, has not experienced any losses in such accounts and believes the exposure to significant risk to the cash balance is minimal.
	In addition, the Company relies on third-party manufacturers for the production of its drug candidate. If the third-party manufacturers are unable to continue manufacturing the Company’s drug candidate, or if the Company loses one of its sole source suppliers used in its manufacturing processes, the Company may not be able to meet clinical trial supply demand for its product candidate and the development of the product candidate could be materially and adversely affected.
Preferred Stock Warrant Liability	'
	Preferred Stock Warrant Liability
	Warrants for shares that are puttable and warrants for shares that are contingently redeemable are classified as liabilities on the accompanying balance sheets and carried at their estimated fair value. At the end of each reporting period, any changes in fair value are recorded as a component of other income (expense). At the completion of the IPO, the Company adjusted the carrying value of the warrants and reclassified the liability to additional paid-in capital.
Stock-Based Compensation	'
	Stock-Based Compensation
	Stock-based compensation expense is recorded at the estimated fair value of the award as of the grant date and is recognized as expense on a straight-line basis over the employee’s requisite service period, which is generally the vesting period of the award. Stock-based compensation expense is based on awards ultimately expected to vest, and therefore, the recorded expense includes an estimate of future forfeitures. Forfeitures are to be estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates.
	Prior to the IPO, the Company granted stock options to purchase common stock to employees with exercise prices equal to the value of the underlying stock, as determined by the board of directors on the date the equity award was granted. The board of directors determined the fair value of the underlying common stock by considering a number of factors, including historical and projected financial results, the risks the Company faced at the time, the preferences of the Company’s preferred stockholders and the lack of liquidity of the Company’s common stock. Subsequent to the IPO, the exercise price of the stock options granted to employees and members of the board of directors of the Company was determined by the Company’s closing market price on the date the stock options were granted.
	The fair value of each option award is estimated on the date of grant using the Black-Scholes valuation model using the appropriate risk-free interest rate, expected term and volatility assumptions. The expected life of options was calculated using the simplified method, which calculates the life as the average of the contractual term of the stock option and the vesting period of the option. Due to the Company’s limited historical data as a public company, the estimated volatility is calculated based upon the historical volatility of the Company and comparable companies whose share prices are publicly available for a sufficient period of time. The risk-free interest rate is based upon U.S. Treasury securities with remaining terms similar to the expected term of the stock award being valued. The Company granted 501,500 options in 2013 and no options in 2012.
Research and Development Expenses	'
	Research and Development Expenses
	Research and development costs are expensed as incurred and primarily include compensation and related benefits, stock-based compensation expense, costs paid to third-party contractors to perform research, conduct clinical trials and develop drug materials and delivery devices. The Company expenses costs relating to the purchase and production of pre-approval inventories as research and development expense in the period incurred until FDA approval is received.
	The Company bases its expense accruals related to clinical studies on estimates of the services received and efforts expended pursuant to contracts with multiple research institutions and clinical research organizations , or CROs, that conduct and manage clinical studies on our behalf. The financial terms of these agreements vary from contract to contract and may result in uneven payment flows. Payments under some of these contracts depend on factors, such as the successful enrollment of patients, site initiation and the completion of clinical study milestones. Service providers invoice us monthly in arrears for services performed. In accruing service fees, the Company estimates the time period over which services will be performed and the level of effort to be expended in each period. If the Company does not identify costs that have begun to be incurred, or if the Company underestimates or overestimates the level of services performed or the costs of these services, actual expenses could differ from estimates. To date, the Company has not experienced significant changes in estimates of accrued research and development expenses after a reporting period. However, due to the nature of estimates, no assurance can be made that changes to the estimates will not be made in the future as the Company becomes aware of additional information about the status or conduct of clinical studies and other research activities.
	We do not own or operate manufacturing facilities for the production of EVK-001, nor do we have plans to develop our own manufacturing operations in the foreseeable future. We currently depend on third-party contract manufacturers for all of our required raw materials, drug substance and finished product for our preclinical research and clinical trials. We do not have any current contractual relationships for the manufacture of commercial supplies of EVK-001. If EVK-001 is approved by any regulatory agency, we intend to enter into agreements with third-party contract manufacturers for the commercial production at that time. We currently utilize a third-party consultant, which we engage on an as-needed, hourly basis, to manage our manufacturing contractors.
Income Taxes	'
	Income Taxes
	The Company accounts for income taxes in accordance with ASC 740, Income Taxes. Under ASC 740, deferred tax assets and liabilities reflect the future tax consequences of the differences between the financial reporting and tax basis of assets and liabilities using current enacted tax rates. The Company provides a valuation allowance against net deferred tax assets unless, based upon the available evidence, it is more likely than not that the deferred tax assets will be realized.
	The Company’s policy related to accounting for uncertainty in income taxes prescribes a recognition threshold and measurement attributed criteria for the financial statement recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more likely than not to be sustained upon examination by taxing authorities.
Comprehensive Income (Loss)	'
	Comprehensive Income (Loss)
	ASC 220, Comprehensive Income, defines comprehensive income (loss) as a change in equity during a period from transactions and other events and circumstances from non-owner sources. Net loss and comprehensive loss were the same for all periods presented.
Net Loss Per Share	'
	Net Loss Per Share
	Basic net loss per share is calculated by dividing the net loss by the weighted-average number of common shares outstanding for the period, without consideration for common stock equivalents and adjusted for the weighted-average number of common shares outstanding that are subject to repurchase. The Company has excluded 103,750, 118,750 and 140,125 weighted-average shares subject to repurchase from the weighted-average number of common shares outstanding for the year ended December 31, 2013, 2012 and 2011, respectively. Diluted net loss per share is calculated by dividing the net loss by the weighted-average number of common share equivalents outstanding for the period determined using the treasury-stock method. Dilutive common stock equivalents are comprised of convertible preferred stock, warrants for the purchase of convertible preferred stock, warrants for the purchase of common stock, and options outstanding under the Company’s equity incentive plans. For the periods presented, there is no difference in the number of shares used to calculate basic and diluted shares outstanding due to the Company’s net loss position.
Recent Accounting Pronouncements	'
	Recent Accounting Pronouncements
	In February 2013, the Financial Accounting Standards Board issued an accounting standard update to require reclassification adjustments from other comprehensive income to be presented either in the financial statements or in the notes to the financial statements. This accounting standard became effective for the Company beginning in the first quarter of 2013, and its adoption did not have any impact on the Company’s financial statements.
	In July 2013, the FASB issued Accounting Standards Update No. 2013-11, presentation of an unrecognized tax benefit when a net operating loss carryforward, a similar tax loss, or a tax credit carryforward exists (“ASU 2013-11”). The guidance is effective prospectively for fiscal years, and interim periods within those years, beginning after December 15, 2013, with an option for early adoption. The Company intends to adopt this guidance during the first quarter of 2014, and does not believe the adoption of this standard will have a material impact on the Company’s consolidated financial statements.

Organization_and_Basis_of_Pres1

Organization and Basis of Presentation (Tables)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Initial Public Offering and Related Transactions	'
	Net proceeds from the IPO, including the exercise of the over-allotment option, were determined as follows:
	Gross proceeds (including over-allotment)	$	28,980,000
	Underwriting discounts and commissions and non-accountable expense allowance		(2,344,875	)
	Total offering costs (excluding value of warrants granted to underwriter of $470,000)		(1,514,177	)
	Net proceeds	$	25,120,948
Assumptions Used in Estimation of Fair Value of Issued Warrant	'
	The fair value of the issued warrants was estimated using the Black-Scholes option pricing model with the following assumptions:
	Assumed risk-free interest rate		1.44	%
	Assumed volatility		71	%
	Expected warrant life		5 Years
	Expected dividend yield		0	%

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Summary of Weighted-Average Anti-Dilutive Securities Excluded from Calculation of Diluted Net Loss Per Share	'
	The following table summarizes the weighted-average anti-dilutive securities excluded from the calculation of diluted net loss per share (in common equivalent shares):
		Year Ended December 31,
		2013		2012		2011
	Convertible preferred stock outstanding		—		2,439,002		2,439,002
	Warrants for convertible preferred stock		—		14,000		10,000
	Warrants for common stock		106,000		—		—
	Common stock options		624,750		123,250		123,250
			730,750		2,576,252		2,572,252

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Fair Value of Outstanding Preferred Stock Warrants	'
	The fair value of the outstanding preferred stock warrants at December 31, 2012 was estimated using the Black-Scholes option pricing model with the following assumptions:
		December 31, 2012
	Assumed risk-free-interest rate		0.25% — 1.78%
	Assumed volatility		80%
	Expected warrant life		2.08 — 9.50 years
	Expected dividend yield		0.00%
Liabilities Measured at Fair Value on Recurring Basis	'
	Liabilities measured at fair value on a recurring basis as of December 31, 2012 are as follows:
					Fair Value Measurements
					at Reporting Date Using
		Balance as of			Quoted Prices		Significant		Significant
		December 31,			in Active		Other		Unobservable
		2012			Markets for		Observable		Inputs
					Identical Assets		Inputs		(Level 3)
					(Level 1)		(Level 2)
	Liabilities:
	Preferred stock warrant liability	$	56,000		$	—	$	—	$	56,000
	Total liabilities		56,000		$	—	$	—	$	56,000
Reconciliation of Company's Liabilities Measured Using Significant Unobservable Inputs	'
	The following table is a reconciliation of all the Company’s liabilities measured using significant unobservable inputs (Level 3) for the years ended December 31, 2013 and 2012:
		Warrant
		Liability
	Fair value measurement at December 31, 2011	$	39,000
	Warrants issued in connection with loan and security agreement		24,250
	Change in fair value of warrant liability		(7,250	)
	Fair value measurement at December 31, 2012		56,000
	Warrants issues in connection with loan and security agreement		49,000
	Change in fair value of warrant liability		82,000
	Reclassification to additional paid-in capital at initial public offering		(187,000	)
	Fair value measurement at December 31, 2013	$	—

Debt_Tables

Debt (Tables)	12 Months Ended
	Dec. 31, 2013
Debt Disclosure [Abstract]	'
Assumptions Used in Estimation of Initial Fair Value of Warrants	'
	The initial fair value of warrants earned in 2013 and 2012 was estimated using the Black-Scholes option pricing model with the following assumptions:
		January 2013			July 2012
	Assumed risk-free interest rate		1.86	%		1.43	%
	Assumed volatility		80	%		80	%
	Expected warrant life		9.5 Years			10 Years
	Expected dividend yield		0	%		0	%
Schedule of Aggregate Advances under the Loan and Security Agreement	'
	The aggregate advances under the loan and security agreement and unamortized discount as of December 31, 2013 and 2012 are as follows:
		December 31,			December 31,
		2013			2012
	Aggregate advances under loan and security agreement	$	3,000,000		$	1,000,000
	Less unamortized discount		(45,947	)		(20,208	)
	Long-term debt, net of debt discount		2,954,053			979,792
	Current portion of unamortized discount		23,260			—
	Current portion of long-term debt		(1,465,852	)		—
	Long-term debt, net of current portion	$	1,511,461		$	979,792
Schedule of Maturities of Long-Term Debt	'
	Maturities of long-term debt as of December 31, 2013, are as follows:
			2014		$	1,572,285
			2015			1,572,285
	Total minimum payments					3,144,570
	Less amount representing interest					(144,570	)
	Total outstanding debt					3,000,000
	Less current portion					(1,465,852	)
	Long-term portion				$	1,534,148

Commitments_Tables

Commitments (Tables)	12 Months Ended
	Dec. 31, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Future Minimum Lease Payments for Operating Lease	'
	As of December 31, 2013, future minimum lease payments for our operating lease are as follows:
	2014	$	75,603
	2015		93,399
	Total	$	169,002

Convertible_Preferred_Stock_Co1

Convertible Preferred Stock, Common Stock and Stockholders' Equity (Deficit) (Tables)	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Summary of Stock Option Activity	'
	A summary of the Company’s stock option activity under the 2007 Plan and 2013 Plan is as follows:
			Shares				Weighted			Weighted		Aggregate
							Average			Average		Intrinsic
							Exercise			Remaining		Value
							Price			Contractual
										Term
										(Years)
	Outstanding at December 31, 2012			123,250			$	0.4			7.84	$	578
	Granted			501,500			$	9.39			9.88		—
	Exercised			—				—			—		—
	Canceled/Forfeited			—				—			—		—
	Outstanding at December 31, 2013			624,750			$	7.61			8.41	$	869,490
	Exercisable at December 31, 2013 (1)			90,540			$	0.39			5.01	$	638,881
	Vested or expected to vest at December 31, 2013			624,750			$	7.61			8.41	$	869,490
	-1	Includes awards with early exercise provisions that permit optionee to exercise unvested options.
Summary of Estimated Fair Value of Stock Option Award Granted	'
	The estimated fair value of each option award granted was determined on the date of grant using the Black-Scholes option-pricing valuation model with the following weighted-average assumptions for options grants during the three years ended December 31, 2013:
			Year Ended December 31,
			2013		2012				2011
	Stock Options
	Risk free interest rate		1.75% - 1.8%			—			2.33%
	Expected option term		6.0 years			—			5.0 years
	Expected volatility of common stock		70.8% - 79.4%			—			80.00%
	Expected dividend yield		—%			—			—%
Summary of Non-Cash Share-Based Compensation Expense	'
	The Company recognized non-cash stock-based compensation expense to employees and directors in its research and development and its general and administrative functions as follows:
			Year Ended December 31,									Period from
												January 29,
												2007
												(Inception) to
												December 31,
			2013				2012			2011		2013
	Research and development		$	39,638			$	10,004		$	15,360	$	93,435
	General and administrative			106,328				2,501			7,345		142,243
	Total stock-based compensation expense		$	145,966			$	12,505		$	22,705	$	235,678
Summary of Common Stock Reserved for Future Issuance	'
	Common stock reserved for future issuance consists of the following at December 31, 2013 and 2012:
			December 31,
			2013				2012
	Conversion of preferred stock			—				2,439,002
	Stock options issued and outstanding			624,750				123,250
	Authorized for future option grants			8,500				—
	Warrants for convertible preferred stock			—				14,000
	Warrants for common stock			106,000				—
	Authorized for Employee Stock Purchase Plan			330,000				—
	Total common stock reserved for future issuance			1,069,250				2,576,252

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Reconciliation of Federal Statutory Income Tax Rate and Effective Income Tax Rate	'
	A reconciliation of the federal statutory income tax rate and the effective income tax rate is as follows for the years ended December 31:
		December 31,
		2013			2012			2011
		(%)			(%)			(%)
	Federal statutory rate		34			34			34
	Change in valuation allowance		(2.5	)		(4.9	)		(0.2	)
	State income taxes, net of federal effect		5.8			5.8			5.8
	Research and development credits		4.3			1.5			4.2
	Removal of net operating loss and other credits		(39.5	)		(36.4	)		(43.9	)
	Other		(2.1	)		(0.0	)		0.1
	Effective income tax rate		0			0			0
Summary of Significant Components of Deferred Tax Assets	'
	Significant components of the Company’s deferred tax assets at December 31, 2013 and 2012 are as follows:
		December 31,
		2013			2012
	Deferred tax assets:
	Acquired technology	$	147,000		$	164,000
	Other, net		290,000			203,000
	Total deferred tax assets		437,000			367,000
	Less valuation allowance		(437,000	)		(367,000	)
	Net deferred tax assets	$	—		$	—

Summarized_Quarterly_Data_Tabl

Summarized Quarterly Data (Tables)	12 Months Ended
	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
Summarized Quarterly Data	'
	Summarized quarterly data for the years ended December 31, 2013 and 2012 are as follows:
			For the Quarters Ended
			March 31,			June 30,			September 30,			December 31,
	2013
	Research and development expense		$	110,981		$	130,846		$	78,731		$	636,423
	General and administrative expense			221,049			72,578			406,862			944,359
	Net loss			(493,992	)		(239,871	)		(485,904	)		(1,616,698	)
	Net loss per share, basic and diluted (1)			(0.44	)		(0.21	)		(0.41	)		(0.27	)
	Weighted average shares outstanding, basic and diluted			1,133,375			1,137,125			1,190,212			5,971,236
	2012
	Research and development expense		$	297,285		$	213,010		$	337,003		$	318,347
	General and administrative expense			205,137			147,328			140,746			343,570
	Net loss			(500,158	)		(358,666	)		(486,254	)		(672,450	)
	Net loss per share, basic and diluted (1)			(0.45	)		(0.32	)		(0.43	)		(0.60	)
	Weighted average shares outstanding, basic and diluted			1,118,375			1,122,125			1,125,875			1,129,625
	-1	Net loss per share is computed independently for each of the quarters presented. Therefore, the sum of the quarterly per-share calculations will not necessarily equal the annual per share calculation.

Organization_and_Basis_of_Pres2

Organization and Basis of Presentation - Additional Information (Detail) (USD $)

0 Months Ended

12 Months Ended

0 Months Ended

12 Months Ended

12 Months Ended

0 Months Ended

Jun. 13, 2013

Dec. 31, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Oct. 08, 2013

IPO [Member]

IPO [Member]

IPO [Member]

IPO [Member]

IPO [Member]

IPO [Member]

IPO [Member]

IPO [Member]

IPO [Member]

Over-allotment option exercise [Member]

Retention bonus expense [Member]

Warrants for common stock [Member]

Warrants for Convertible Preferred Stock [Member]

Warrants for common stock converted from warrants for preferred stock [Member]

Executive Officers [Member]

Executive Officers [Member]

Underwriters and Affiliates [Member]

Underwriters [Member]

Retention bonus expense [Member]

Catch-up retention bonus expense [Member]

Warrants for common stock [Member]

Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

Date of Incorporation

'

29-Jan-07

'

'

'

'

'

'

'

'

'

'

'

Deficit accumulated during the development stage

'

$22,691,468

$19,855,003

'

'

'

'

'

'

'

'

'

'

Working capital (deficit)

'

22,146,047

-454,396

'

'

'

'

'

'

'

'

'

'

Reverse stock split of issued and outstanding shares

'One-for-five

'

'

'

'

'

'

'

'

'

'

'

'

Reverse stock split effective date

'

30-Aug-13

'

'

'

'

'

'

'

'

'

'

'

Common stock shares sold

'

'

'

2,100,000

'

'

'

'

'

'

'

'

315,000

Common stock shares price per share

'

'

'

$12

'

'

'

'

'

'

'

'

$12

Conversion of convertible preferred stock

'

'

'

'

2,439,002

'

'

'

'

'

'

'

'

Retention bonus payable to executive officers

'

'

'

'

'

'

'

'

'

355,000

202,857

'

'

Retention bonuses accounting treatment

'

'

'

'

'

'Such amount was recorded as expense on a straight-line basis from May 22, 2013 (the date of the retention agreements entered into with the executive officers) through December 24, 2013, the date at which the final payment was due based on continued employment.

'

'

'

'

'

'

'

Number of shares callable by warrants

'

'

'

'

'

'

'

110,000

22,000

'

'

84,000

'

Warrants exercise price per share

'

'

'

'

'

'

21

'

'

'

'

'

'

Warrants exercisable start date

'

'

'

'

'

'

24-Sep-14

'

'

'

'

'

'

Warrants expiration date

'

1-Jun-22

'

'

'

'

24-Sep-18

'

'

'

'

'

'

Initial fair value of warrants

'

'

'

'

'

'

470,000

'

'

'

'

'

'

Warrant liability to additional paid-in capital

'

$187,000

'

'

'

'

'

'

$187,000

'

'

'

'

Common stock authorized

'

50,000,000

20,000,000

'

'

'

'

'

'

'

'

'

'

Preferred stock authorized

'

5,000,000

0

'

'

'

'

'

'

'

'

'

'

Organization_and_Basis_of_Pres3

Organization and Basis of Presentation - Initial Public Offering and Related Transactions (Detail) (USD $)	12 Months Ended	83 Months Ended
	Dec. 31, 2013	Dec. 31, 2013
Equity [Abstract]	'	'
Gross proceeds (including over-allotment)	$28,980,000	'
Underwriting discounts and commissions and non-accountable expense allowance	-2,344,875	'
Total offering costs (excluding value of warrants granted to underwriter of $470,000)	-1,514,177	'
Net proceeds	$25,120,948	$25,125,528

Organization_and_Basis_of_Pres4

Organization and Basis of Presentation - Initial Public Offering and Related Transactions (Parenthetical) (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Value of warrants granted to underwriters	$470,000

Organization_and_Basis_of_Pres5

Organization and Basis of Presentation - Assumptions Used in Estimation of Fair Value of Issued Warrant (Detail)	1 Months Ended		12 Months Ended
	Jan. 31, 2013	Jul. 31, 2012	Dec. 31, 2013
Accounting Policies [Abstract]	'	'	'
Assumed risk-free interest rate	1.86%	1.43%	1.44%
Assumed volatility	80.00%	80.00%	71.00%
Expected warrant life	'9 years 6 months	'10 years	'5 years
Expected dividend yield	0.00%	0.00%	0.00%

Summary_of_Significant_Account3

Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	Segment
Earnings Per Share [Abstract]	'	'	'
Number of operating segment	1	'	'
Number of stock options granted	501,500	0	'
Weighted-average shares subject to repurchase from the weighted-average number of common shares outstanding	103,750	118,750	140,125

Summary_of_Significant_Account4

Summary of Significant Accounting Policies - Summary of Weighted-Average Anti-Dilutive Securities Excluded from Calculation of Diluted Net Loss Per Share (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'
Weighted-average anti-dilutive securities excluded from the calculation of diluted net loss per share	730,750	2,576,252	2,572,252
Conversion of preferred stock [Member]	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'
Weighted-average anti-dilutive securities excluded from the calculation of diluted net loss per share	'	2,439,002	2,439,002
Warrants for Convertible Preferred Stock [Member]	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'
Weighted-average anti-dilutive securities excluded from the calculation of diluted net loss per share	'	14,000	10,000
Warrants for common stock [Member]	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'
Weighted-average anti-dilutive securities excluded from the calculation of diluted net loss per share	106,000	'	'
Stock options issued and outstanding [Member]	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'
Weighted-average anti-dilutive securities excluded from the calculation of diluted net loss per share	624,750	123,250	123,250

Fair_Value_Measurements_Additi

Fair Value Measurements - Additional Information (Detail) (USD $)	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Financial liabilities	$0

Fair_Value_Measurements_Fair_V

Fair Value Measurements - Fair Value of Outstanding Preferred Stock Warrants (Detail)	1 Months Ended		12 Months Ended
	Jan. 31, 2013	Jul. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2012
				Preferred stock warrant liability [Member]	Preferred stock warrant liability [Member]	Preferred stock warrant liability [Member]
					Minimum [Member]	Maximum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]	'	'	'	'	'	'
Assumed risk-free interest rate	1.86%	1.43%	1.44%	'	0.25%	1.78%
Assumed volatility	80.00%	80.00%	71.00%	80.00%	'	'
Expected warrant life	'9 years 6 months	'10 years	'5 years	'	'2 years 29 days	'9 years 6 months
Expected dividend yield	0.00%	0.00%	0.00%	0.00%	'	'

Fair_Value_Measurements_Liabil

Fair Value Measurements - Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2012
		Fair value, recurring basis [Member]	Fair value, recurring basis [Member]	Fair value, recurring basis [Member]	Fair value, recurring basis [Member]	Fair value, recurring basis [Member]	Fair value, recurring basis [Member]	Fair value, recurring basis [Member]	Fair value, recurring basis [Member]
			Preferred stock warrant liability [Member]	Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	Significant Other Observable Inputs (Level 2) [Member]	Significant Other Observable Inputs (Level 2) [Member]	Significant Unobservable Inputs (Level 3) [Member]	Significant Unobservable Inputs (Level 3) [Member]
					Preferred stock warrant liability [Member]		Preferred stock warrant liability [Member]		Preferred stock warrant liability [Member]
Liabilities:	'	'	'	'	'	'	'	'	'
Total liabilities	$0	$56,000	$56,000	'	'	'	'	$56,000	$56,000

Fair_Value_Measurements_Reconc

Fair Value Measurements - Reconciliation of Company's Liabilities Measured Using Significant Unobservable Inputs (Detail) (USD $)	12 Months Ended			83 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'	'	'	'
Beginning balance	$56,000	$39,000	'	'
Warrants issued in connection with loan and security agreement	49,000	24,250	'	'
Change in fair value of warrant liability	82,000	-7,250	-5,500	54,264
Reclassification to additional paid-in capital at initial public offering	-187,000	'	'	'
Ending balance	'	$56,000	$39,000	'

Debt_Additional_Information_De

Debt - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended
	Jun. 30, 2012	Dec. 31, 2013	Dec. 31, 2012	Jan. 31, 2013	Jul. 31, 2012
Debt Instrument [Line Items]	'	'	'	'	'
Loan and security agreement, expiration date	'	1-Jun-22	'	'	'
Unamortized debt discount, related to the initial fair value of warrants	'	$45,947	$20,208	'	'
Loan and security agreement [Member]	'	'	'	'	'
Debt Instrument [Line Items]	'	'	'	'	'
Loan and security agreement, maximum credit	3,000,000	'	'	'	'
Loan and security agreement, interest rate	4.50%	'	'	'	'
Loan and security agreement, payback period	'24 months	'	'	'	'
Loan and security agreement, amount drawn	'	'	'	2,000,000	1,000,000
Loan and security agreement, available credit	'	0	2,000,000	'	'
Loan and security agreement, interest incurred	'	136,625	20,000	'	'
Loan and security agreement [Member] | Warrants for Convertible Preferred Stock [Member]	'	'	'	'	'
Debt Instrument [Line Items]	'	'	'	'	'
Warrants exercisable, stock issued	'	'	'	8,000	'
Warrants exercisable, exercise price	'	'	'	7.5	'
Loan and security agreement [Member] | Series A Convertible Preferred Stock [Member] | Warrants for Convertible Preferred Stock [Member]	'	'	'	'	'
Debt Instrument [Line Items]	'	'	'	'	'
Warrants exercisable, stock issued	'	'	'	8,000	4,000
Warrants exercisable, exercise price	'	'	'	7.5	7.5
Initial fair value of warrant issued	'	'	'	$49,000	$24,250

Debt_Assumptions_Used_in_Estim

Debt - Assumptions Used in Estimation of Initial Fair Value of Warrants (Detail)	1 Months Ended		12 Months Ended
	Jan. 31, 2013	Jul. 31, 2012	Dec. 31, 2013
Debt Disclosure [Abstract]	'	'	'
Assumed risk-free interest rate	1.86%	1.43%	1.44%
Assumed volatility	80.00%	80.00%	71.00%
Expected warrant life	'9 years 6 months	'10 years	'5 years
Expected dividend yield	0.00%	0.00%	0.00%

Debt_Schedule_of_Aggregate_Adv

Debt - Schedule of Aggregate Advances under the Loan and Security Agreement (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Debt Disclosure [Abstract]	'	'
Aggregate advances under loan and security agreement	$3,000,000	$1,000,000
Less unamortized discount	-45,947	-20,208
Long-term debt, net of debt discount	2,954,053	979,792
Current portion of unamortized discount	23,260	'
Current portion of long-term debt	-1,465,852	'
Long-term debt, net of current portion	$1,511,461	$979,792

Debt_Schedule_of_Maturities_of

Debt - Schedule of Maturities of Long-Term Debt (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Maturities Of Long Term Debt [Abstract]	'	'
2014	$1,572,285	'
2015	1,572,285	'
Total minimum payments	3,144,570	'
Less amount representing interest	-144,570	'
Total outstanding debt	3,000,000	1,000,000
Less current portion	-1,465,852	'
Long-term portion	$1,534,148	'

Commitments_Additional_Informa

Commitments - Additional Information (Detail) (USD $)	12 Months Ended			83 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013
Commitments And Contingencies Disclosure [Abstract]	'	'	'	'
Lease commencement date	'December 1, 2013	'	'	'
Lease expiry date	31-Dec-15	'	'	'
Rent expense	$8,886	$5,000	$12,000	$57,686
Deferred rent expense	$6,830	$0	'	$6,830

Commitments_Future_Minimum_Lea

Commitments - Future Minimum Lease Payments for Operating Lease (Detail) (USD $)	Dec. 31, 2013
Commitments And Contingencies Disclosure [Abstract]	'
2014	$75,603
2015	93,399
Total future minimum lease payments	$169,002

Acquisition_of_Technology_Addi

Acquisition of Technology - Additional Information (Detail) (USD $)	1 Months Ended	83 Months Ended			12 Months Ended
	Jun. 30, 2007	Dec. 31, 2013	Jun. 30, 2007	Jun. 30, 2007	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2013
			Questcor [Member]	Development Target One, Two and Three [Member]	Development Target One [Member]	Development Target Two [Member]	Development Target Three [Member]	Development Target Four [Member]
			Patents [Member]	Questcor [Member]	Questcor [Member]	Questcor [Member]	Questcor [Member]	Questcor [Member]
				Patents [Member]	Patents [Member]	Patents [Member]	Patents [Member]	Patents [Member]
Business Acquisition, Contingent Consideration [Line Items]	'	'	'	'	'	'	'	'
Upfront payment expensed as in-process research and development	$650,000	$650,000	'	'	'	'	'	'
Milestone payments	'	'	52,000,000	'	'	'	'	'
Milestone payments, pegged to development targets	'	'	'	$5,000,000	$500,000	$1,500,000	$3,000,000	$47,000,000
Development targets description	'	'	'	'	'Upon the initiation of the first patient dosing in the Company's planned Phase 3 clinical trial for EVK-001	'Upon the U.S. Food and Drug Administration's (the "FDA") acceptance for review of a new drug application for EVK-001	'Upon the FDA's approval of EVK-001	'Depend on EVK-001's commercial success and will only apply if EVK-001 receives regulatory approval. In addition, the Company will be required to pay to Questcor a low single digit royalty on net sales of EVK-001.
Expected expiration of patent right	'	'	'	'	'	'	'	'2030

Convertible_Preferred_Stock_Co2

Convertible Preferred Stock, Common Stock and Stockholders' Equity (Deficit) - Convertible Preferred Stock - Additional Information (Detail) (USD $)

12 Months Ended

5 Months Ended

12 Months Ended

5 Months Ended

1 Months Ended

5 Months Ended

12 Months Ended

Dec. 31, 2013

Dec. 31, 2012

Oct. 31, 2007

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Oct. 31, 2007

Dec. 31, 2007

Oct. 31, 2007

Jun. 30, 2010

Nov. 30, 2008

Oct. 31, 2007

Dec. 31, 2013

Convertible promissory notes [Member]

Common Stock [Member]

Series A Convertible Preferred Stock [Member]

Series A Convertible Preferred Stock [Member]

Series A Convertible Preferred Stock [Member]

Series A Convertible Preferred Stock [Member]

Series A Convertible Preferred Stock [Member]

Private Placement [Member]

Private Placement [Member]

Private Placement [Member]

Private Placement [Member]

Convertible promissory notes [Member]

Purchase right liability [Member]

Purchase right liability [Member]

Series A Convertible Preferred Stock [Member]

Series A Convertible Preferred Stock [Member]

Series A Convertible Preferred Stock [Member]

Series A Convertible Preferred Stock [Member]

Sale Of Stock [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of shares sold in transaction

'

'

'

'

'

'

'

'

'

4,000,001

4,000,000

4,000,000

'

Sale of stock, price per share

'

'

'

'

'

'

'

'

'

$1.50

$1.50

$1.50

'

Gross proceeds from sale of stock

'

'

'

'

'

'

'

'

'

$6,000,002

$6,000,000

$6,000,000

'

Debt instrument face amount

'

'

250,000

'

'

'

'

'

'

'

'

'

'

Debt instrument accrued interest

'

'

42,538

'

'

'

'

'

'

'

'

'

'

Conversion of convertible preferred stock

'

'

195,067

2,439,002

'

'

'

'

'

'

'

'

'

Proceeds from the sale of stock allocated to the preferred stock purchase right liability

'

'

'

'

'

'

848,257

'

'

'

'

'

'

Offering costs

'

'

'

'

'

'

218,037

'

'

36,069

1,855

'

'

Increase in fair value recorded as other expense

'

'

'

'

'

'

'

68,955

4,132

'

115,500

'

'

Fair value reclassified to preferred stock

'

'

'

'

'

'

'

'

80,819

'

956,025

'

'

Noncumulative dividends rate, per share per annum

'

'

'

'

'

'

'

'

'

'

'

'

$0.12

Dividends declared

$0

'

'

'

$0

'

'

'

'

'

'

'

'

Liquidation preferences

'

'

'

'

'

'

'

'

'

'

'

'

$1.50

Terms of conversion

'

'

'

'

'

'

'

'

'

'

'

'

'The shares of Series A Convertible Preferred Stock are convertible into one share of common stock for each five shares of preferred stock, at the option of the holder, subject to certain anti-dilutive adjustments. Each share of Series A Convertible Preferred Stock is automatically converted into common stock immediately upon the earlier of (i) the Company's sale of its common stock in a firm commitment underwritten public offering pursuant to a registration statement under the Securities Act of 1933, as amended, in which the per share price is at least $22.50 (as adjusted), and the gross cash proceeds are at least $25,000,000 or (ii) the date specified by written consent or agreement of the holders of not less than 66.66% of the then outstanding shares of Series A Convertible Preferred Stock.

Price per share threshold, conversion description

'

'

'

'

'

'

'

'

'

'

'

'

$22.50

Gross cash proceeds threshold, conversion description

'

'

'

'

'

'

'

'

'

'

'

'

$25,000,000

Shareholders consent percentage threshold, conversion description

'

'

'

'

'

'

'

'

'

'

'

'

66.66%

Shareholders voting power description

'

'

'

'Each share of common stock is entitled to one vote. The holders of the common stock are also entitled to receive dividends whenever funds are legally available and when declared by the board of directors of the Company.

'One vote for each share of common stock into which such Series A Convertible Preferred Stock could then be converted; and with respect to such vote, such holder had full voting rights and powers equal to the voting rights and powers of the holders of common stock.

'

'

'

'

'

'

'

'

Shareholders voting power number of shares threshold

'

'

'

'

'

'

'

'

'

'

'

'

250,000

Preferred stock, shares authorized

5,000,000

0

'

'

0

12,305,068

'

'

'

'

'

'

'

Preferred stock, par value

$0.00

'

'

'

'

$0.00

'

'

'

'

'

'

'

Preferred stock shares issued

0

0

'

'

0

12,195,068

'

'

'

'

'

'

'

Preferred stock shares outstanding

0

0

'

'

0

12,195,068

'

'

'

'

'

'

'

Common stock, shares outstanding

6,096,752

1,242,750

'

'

'

'

'

'

'

'

'

'

'

Convertible_Preferred_Stock_Co3

Convertible Preferred Stock, Common Stock and Stockholders' Equity (Deficit) - Stock Options - Additional Information (Detail) (USD $)	12 Months Ended					1 Months Ended		12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2012	31-May-07	Dec. 31, 2013
				Minimum [Member]	Maximum [Member]	2007 Equity Incentive Plan [Member]	2007 Equity Incentive Plan [Member]	2013 Equity Incentive Award Plan [Member]
Subsidiary, Sale of Stock [Line Items]	'	'	'	'	'	'	'	'
Common stock reserved for issuance	1,069,250	2,576,252	'	'	'	'	450,000	510,000
Options available for future grant	501,500	0	'	'	'	0	'	'
Additional common stock reserved for issuance	'	'	'	'	'	'	'	300,000
Shares of common stock available for issuance description	'	'	'	'	'	'	'	'In addition, the number of shares of common stock available for issuance under the 2013 Plan will be annually increased on the first day of each fiscal year during the term of the 2013 Plan, beginning with the 2014 fiscal year, by an amount equal to the least of (i) 300,000 shares; (ii) four percent of the outstanding shares of common stock as of the last day of the immediately preceding fiscal year; or (iii) such other amount as the Company's board of directors may determine.
Reserve percentage for issuance of shares	'	'	'	'	'	'	'	4.00%
Options available for future grant	'	'	'	'	'	'	'	8,500
Options granted, weighted average term	'	'	'	'7 years	'10 years	'	'	'
Options granted, vesting period	'	'	'	'3 years	'4 years	'	'	'
Intrinsic value, common stock price	$7.45	$0.40	'	'	'	'	'	'
Stock options exercised	326,750	'	'	'	'	'	'	'
Stock options vested	230,500	215,500	'	'	'	'	'	'
Total intrinsic value of stock options exercised	$0	$0	$0	'	'	'	'	'
Weighted average grant date fair value per share	$6.33	$0	$0.05	'	'	'	'	'

Convertible_Preferred_Stock_Co4

Convertible Preferred Stock, Common Stock and Stockholders' Equity (Deficit) - Summary of Stock Option Activity (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'	'
Shares, Outstanding beginning balance	123,250	'
Shares, Granted	501,500	0
Shares, Exercised	'	'
Shares, Canceled/Forfeited	'	'
Shares, Outstanding ending balance	624,750	123,250
Shares, Exercisable at December 31, 2013	90,540	'
Shares, Vested or expected to vest at December 31, 2013	624,750	'
Weighted Average Exercise Price, Outstanding beginning balance	$0.40	'
Weighted Average Exercise Price, Granted	$9.39	'
Weighted Average Exercise Price, Exercised	'	'
Weighted Average Exercise Price, Canceled/Forfeited	'	'
Weighted Average Exercise Price, ending balance	$7.61	$0.40
Weighted Average Exercise Price, Exercisable at December 31, 2013	$0.39	'
Weighted Average Exercise Price, Vested or expected to vest at December 31, 2013	$7.61	'
Weighted Average Remaining Contractual Term (Years), Granted	'9 years 10 months 17 days	'
Weighted Average Remaining Contractual Term (Years), Exercised	'	'
Weighted Average Remaining Contractual Term (Years), Canceled/Forfeited	'	'
Weighted Average Remaining Contractual Term (Years), Outstanding	'8 years 4 months 28 days	'7 years 10 months 2 days
Weighted Average Remaining Contractual Term (Years), Exercisable at December 31, 2013	'5 years 4 days	'
Weighted Average Remaining Contractual Term (Years), Vested or expected to vest at December 31, 2013	'8 years 4 months 28 days	'
Aggregate Intrinsic Value, Outstanding beginning balance	$578	'
Aggregate Intrinsic Value, Granted	'	'
Aggregate Intrinsic Value, Exercised	'	'
Aggregate Intrinsic Value, Canceled/Forfeited	'	'
Aggregate Intrinsic Value, Outstanding ending balance	869,490	578
Aggregate Intrinsic Value, Exercisable at December 31, 2013	638,881	'
Aggregate Intrinsic Value, Vested or expected to vest at December 31, 2013	$869,490	'

Convertible_Preferred_Stock_Co5

Convertible Preferred Stock, Common Stock and Stockholders' Equity (Deficit) - Summary of Estimated Fair Value of Stock Option Award Granted (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'	'	'
Risk free interest rate, minimum	1.75%	'	'
Risk free interest rate, maximum	1.80%	'	'
Risk free interest rate	'	'	2.33%
Expected option term	'6 years	'	'5 years
Expected volatility of common stock, minimum	70.80%	'	'
Expected volatility of common stock, maximum	79.40%	'	'
Expected volatility of common stock	'	'	80.00%
Expected dividend yield	'	'	'

Convertible_Preferred_Stock_Co6

Convertible Preferred Stock, Common Stock and Stockholders' Equity (Deficit) - Summary of Non-Cash Share-Based Compensation Expense (Detail) (USD $)	12 Months Ended			83 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Total stock-based compensation expense	$145,966	$12,505	$22,705	$235,677
Research and development [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Total stock-based compensation expense	39,638	10,004	15,360	93,435
General and administrative [Member]	'	'	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'	'
Total stock-based compensation expense	$106,328	$2,501	$7,345	$142,243

Convertible_Preferred_Stock_Co7

Convertible Preferred Stock, Common Stock and Stockholders' Equity (Deficit) - Stock-Based Compensation and Employee Stock Purchase Plan - Additional Information (Detail) (USD $)	12 Months Ended		0 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Jun. 13, 2013	Dec. 31, 2013
			Employee Stock Purchase Plan [Member]	Employee Stock Purchase Plan [Member]
Subsidiary, Sale of Stock [Line Items]	'	'	'	'
Unrecognized compensation costs	$3,055,000	$26,000	'	'
Weighted average period	'1 year 10 months 2 days	'2 years	'	'
Percentage of deduction of eligible compensation	'	'	20.00%	'
Shares of common stock available for issuance	1,069,250	2,576,252	30,000	'
Shares of common stock available for issuance description	'	'	'	'In addition, the number of shares of common stock available for issuance under the ESPP will be annually increased on the first day of each fiscal year during the term of the ESPP, beginning with the 2014 fiscal year, by an amount equal to the least of (i) 30,000 shares; (ii) one percent of the outstanding shares of common stock as of the last day of the immediately preceding fiscal year; or (iii) such other amount as the Company's board of directors may determine.
Reserve percentage for issuance of shares	'	'	1.00%	'
ESPP approval date	'	'	29-Aug-13	'
Shares of common stock issued under ESPP	'	'	'	0

Convertible_Preferred_Stock_Co8

Convertible Preferred Stock, Common Stock and Stockholders' Equity (Deficit) - Summary of Common Stock Reserved for Future Issuance (Detail)	Dec. 31, 2013	Dec. 31, 2012
Class of Stock [Line Items]	'	'
Total common stock reserved for future issuance	1,069,250	2,576,252
Conversion of preferred stock [Member]	'	'
Class of Stock [Line Items]	'	'
Total common stock reserved for future issuance	'	2,439,002
Stock options issued and outstanding [Member]	'	'
Class of Stock [Line Items]	'	'
Total common stock reserved for future issuance	624,750	123,250
Authorized for future option grants [Member]	'	'
Class of Stock [Line Items]	'	'
Total common stock reserved for future issuance	8,500	'
Warrants for Convertible Preferred Stock [Member]	'	'
Class of Stock [Line Items]	'	'
Total common stock reserved for future issuance	'	14,000
Warrants for common stock [Member]	'	'
Class of Stock [Line Items]	'	'
Total common stock reserved for future issuance	106,000	'
Authorized for Employee Stock Purchase Plan [Member]	'	'
Class of Stock [Line Items]	'	'
Total common stock reserved for future issuance	330,000	'

Employee_Benefit_Plan_Addition

Employee Benefit Plan - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013
Postemployment Benefits [Abstract]	'
Eligible age for employees for participating in the plan	'21 years
Company's contributions to employee benefit plan	$0

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Jan. 02, 2009
Operating Loss Carryforwards [Line Items]	'	'	'
Likelihood of unfavorable settlement	'An uncertain tax position will not be recognized if it has a less than 50% likelihood of being sustained.	'	'
Unrecognized tax benefits	'	'	$0
Unrecognized tax benefits that would affect company's effective tax rate, if recognized	0	0	'
Accrual on interest and penalties related to income taxes	0	0	'
Tax years subject to examination by taxing authorities	'Beginning 2007 to date	'	'
Net operating loss carryforwards	8,400,000	'	'
Cumulative change in ownership for limitation of use of net operating loss and research and development credit carryforwards	50.00%	'	'
Period of cumulative change of ownership	'3 years	'	'
Research and development credit	931,000	'	'
Federal [Member]	'	'	'
Operating Loss Carryforwards [Line Items]	'	'	'
Net operating loss carryforwards	21,200,000	'	'
Expiry period of carryforwards	'2027	'	'
Tax credit carryforwards	627,000	'	'
Expiry of federal research credit carryforwards	'2027	'	'
State [Member]	'	'	'
Operating Loss Carryforwards [Line Items]	'	'	'
Net operating loss carryforwards	20,700,000	'	'
Expiry period of carryforwards	'2017	'	'
Tax credit carryforwards	$459,000	'	'

Income_Taxes_Reconciliation_of

Income Taxes - Reconciliation of Federal Statutory Income Tax Rate and Effective Income Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]	'	'	'
Federal statutory rate	34.00%	34.00%	34.00%
Change in valuation allowance	-2.50%	-4.90%	-0.20%
State income taxes, net of federal effect	5.80%	5.80%	5.80%
Research and development credits	4.30%	1.50%	4.20%
Removal of net operating loss and other credits	-39.50%	-36.40%	-43.90%
Other	-2.10%	0.00%	0.10%
Effective income tax rate	0.00%	0.00%	0.00%

Income_Taxes_Summary_of_Signif

Income Taxes - Summary of Significant Components of Deferred Tax Assets (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Deferred tax assets:	'	'
Acquired technology	$147,000	$164,000
Other, net	290,000	203,000
Total deferred tax assets	437,000	367,000
Less valuation allowance	-437,000	-367,000
Net deferred tax assets	'	'

Summarized_Quarterly_Data_Summ

Summarized Quarterly Data - Summarized Quarterly Data (Detail) (USD $)	3 Months Ended								11 Months Ended	12 Months Ended						83 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2007	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'	'	'	'	'	'	'	'	'	'	'	'	'	'	'	'
Research and development expense	$636,423	$78,731	$130,846	$110,981	$318,347	$337,003	$213,010	$297,285	'	$956,980	$1,165,645	$1,844,044	'	'	'	$16,948,509
General and administrative expense	944,359	406,862	72,578	221,049	343,570	140,746	147,328	205,137	'	1,644,848	836,781	570,524	'	'	'	4,949,381
Net loss	($1,616,698)	($485,904)	($239,871)	($493,992)	($672,450)	($486,254)	($358,666)	($500,158)	($2,009,591)	($2,836,465)	($2,017,528)	($2,401,244)	($5,039,338)	($5,159,638)	($3,227,664)	($22,691,468)
Net loss per share, basic and diluted	($0.27)	($0.41)	($0.21)	($0.44)	($0.60)	($0.43)	($0.32)	($0.45)	'	($1.20)	($1.79)	($2.18)	'	'	'	'
Weighted average shares outstanding, basic and diluted	5,971,236	1,190,212	1,137,125	1,133,375	1,129,625	1,125,875	1,122,125	1,118,375	'	2,368,006	1,124,000	1,102,625	'	'	'	'