Summary of Significant Accounting Policies | 2. Summary of Significant Accounting Policies The accompanying condensed balance sheet as of December 31, 2014, which has been derived from audited financial statements, and the unaudited interim condensed financial statements, have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) and follow the requirements of the U.S. Securities and Exchange Commission (“SEC”) for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by GAAP can be condensed or omitted. In management’s opinion, the unaudited interim financial statements have been prepared on the same basis as the audited financial statements and include all adjustments, which include only normal recurring adjustments, necessary for the fair presentation of the Company’s financial position and its results of operations and its cash flows for the periods presented. These statements do not include all disclosures required by GAAP and should be read in conjunction with the Company’s financial statements and accompanying notes for the fiscal year ended December 31, 2014, which are contained in the Company’s Annual Report on Form 10-K filed with the SEC on March 4, 2015. In its report on the Company’s financial statements for the year ended December 31, 2014, the Company’s independent registered public accounting firm included an explanatory paragraph expressing substantial doubt regarding the Company’s ability to continue as a going concern, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business. The results for interim periods are not necessarily indicative of the results expected for the full fiscal year or any other interim period. Use of Estimates 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 materially from those estimates. Stock-Based Compensation Stock-based compensation expense for stock option grants and employee stock purchases under the Company’s Employee Stock Purchase Plan (the “ESPP”) 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. The estimation of stock option and ESPP fair value requires management to make estimates and judgments about, among other things, employee exercise behavior, forfeiture rates and volatility of the Company’s common stock. The judgments directly affect the amount of compensation expense that will be recognized. Prior to the Company’s initial public offering (“IPO”) in September 2013, the Company granted stock options to purchase common stock to employees with exercise prices equal to the estimated fair 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 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 weighted average expected term of options and employee stock purchases 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 as necessary with historical volatility of comparable companies in the biotechnology industry whose share prices are publicly available for a sufficient period of time. 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. Research and Development Expenses Research and development costs are expensed as incurred and primarily include compensation and related benefits, stock-based compensation expense and 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 U.S. Food and Drug Administration (“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 contract research organizations (“CROs”) that conduct and manage clinical studies on its 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 typically invoice the Company 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 materially 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. Included in research and development expenses were costs of $71,019 and $28,274 for the three months ended June 30, 2015 and 2014, respectively, and $159,044 and $28,274 for the six months ended June 30, 2015 and 2014, respectively, incurred by a related party of one of the Company’s officers who serves on the executive management team of a CRO that provides clinical trial services to the Company. The Company does not own or operate manufacturing facilities for the production of EVK-001, nor does it plan to develop its own manufacturing operations in the foreseeable future. The Company currently depends on third-party contract manufacturers for all of its required raw materials, drug substance and finished product for its preclinical research and clinical trials. The Company does not have any current contractual relationships for the manufacture of commercial supplies of EVK-001. If EVK-001 is approved by any regulatory agency, the Company intends to enter into agreements with third-party contract manufacturers for the commercial production at that time. The Company currently utilizes a third-party consultant, which it engages on an as-needed, hourly basis, to manage its manufacturing contractors. 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 45,000 and 71,875 weighted-average shares subject to repurchase from the weighted-average number of common shares outstanding for the three months ended June 30, 2015 and 2014, respectively. In addition, the Company has excluded 45,000 and 83,125 weighted-average shares subject to repurchase from the weighted-average number of common shares outstanding for the six months ended June 30, 2015 and 2014, 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 warrants for the purchase of common stock, options outstanding under the Company’s equity incentive plans and potential shares to be purchased under the ESPP. 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 sets forth the outstanding potentially dilutive securities that have been excluded from the calculation of diluted net loss per share because to do so would be anti-dilutive: Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Warrants to purchase common stock 118,881 96,000 118,881 96,000 Common stock options 1,037,500 688,750 1,037,500 688,750 Employee stock purchase plan 7,208 4,021 10,529 5,362 Total excluded securities 1,163,589 788,771 1,166,910 790,112 Recent Accounting Pronouncements In April 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update 2015-03, Interest – Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs During the quarter ended June 30, 2015, there were no other new accounting pronouncements or updates to recently issued accounting pronouncements disclosed in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2014 that affect the Company’s results of operations, financial condition, liquidity or disclosures. |