Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2017	Apr. 26, 2017
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q1
Trading Symbol	MNOV
Entity Registrant Name	MEDICINOVA INC
Entity Central Index Key	0001226616
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		34,540,543

Consolidated Balance Sheets - USD ($)	Mar. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 21,637,156	$ 24,118,037
Prepaid expenses and other current assets	687,188	585,810
Total current assets	22,324,344	24,703,847
Goodwill	9,600,240	9,600,240
In-process research and development	4,800,000	4,800,000
Investment in joint venture	615,968	618,330
Property and equipment, net	83,793	90,717
Total assets	37,424,345	39,813,134
Current liabilities:
Accounts payable	158,140	367,275
Accrued expenses	863,812	1,262,800
Total current liabilities	1,021,952	1,630,075
Long-term deferred rent and lease liability	798	967
Deferred tax liability	1,956,000	1,956,000
Long-term deferred revenue	1,694,163	1,694,163
Total liabilities	4,672,913	5,281,205
Commitments and contingencies
Stockholders’ equity:
Common stock, $0.001 par value; 100,000,000 shares authorized at March 31, 2017 and December 31, 2016; 34,540,453 and 34,523,678 shares issued and outstanding at March 31, 2017 and December 31, 2016, respectively	34,541	34,525
Additional paid-in capital	366,120,763	364,886,468
Accumulated other comprehensive loss	(94,284)	(96,000)
Accumulated deficit	(333,309,588)	(330,293,064)
Total stockholders’ equity	32,751,432	34,531,929
Total liabilities and stockholders' equity	$ 37,424,345	$ 39,813,134

Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2017	Dec. 31, 2016
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	34,540,453	34,523,678
Common stock, shares outstanding	34,540,453	34,523,678

Consolidated Statements of Operations and Comprehensive Loss - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Operating expenses:
Research, development and patents	$ 900,661	$ 1,075,321
General and administrative	2,122,861	2,316,254
Total operating expenses	3,023,522	3,391,575
Operating loss	(3,023,522)	(3,391,575)
Other expense	(4,447)	(3,267)
Other income	15,505	14,749
Loss before income taxes	(3,012,464)	(3,380,093)
Income taxes	(4,060)	(1,505)
Net loss applicable to common stockholders	$ (3,016,524)	$ (3,381,598)
Basic and diluted net loss per common share	$ (0.09)	$ (0.11)
Shares used to compute basic and diluted net loss per common share	34,527,100	30,356,674
Net loss applicable to common stockholders	$ (3,016,524)	$ (3,381,598)
Other comprehensive loss, net of tax:
Foreign currency translation adjustments	1,716	9,707
Comprehensive loss	$ (3,014,808)	$ (3,371,891)

Consolidated Statements of Cash Flows - USD ($)	3 Months Ended
Consolidated Statements of Cash Flows - USD ($)	Mar. 31, 2017	Mar. 31, 2016
Operating activities:
Net loss	$ (3,016,524)	$ (3,381,598)
Adjustments to reconcile net loss to net cash used in operating activities:
Non-cash stock-based compensation	1,168,155	1,439,149
Depreciation and amortization	7,217	4,105
Change in equity method investment	2,362	13
Changes in assets and liabilities:
Prepaid expenses and other assets	(96,699)	(41,744)
Accounts payable, accrued liabilities and other current liabilities	(611,782)	(439,291)
Net cash used in operating activities	(2,547,271)	(2,419,366)
Investing activities:
Acquisition of property and equipment		(22,005)
Net cash used in investing activities		(22,005)
Financing activities:
Proceeds from issuance of common stock, exercise of common stock options and warrants, net of issuance costs	1,132	7,926,410
Proceeds from issuance of equity awards under ESPP	65,025	49,923
Net cash provided by financing activities	66,157	7,976,333
Effect of exchange rate changes on cash and cash equivalents	233	6,682
Net (decrease) increase in cash and cash equivalents	(2,480,881)	5,541,644
Cash and cash equivalents, beginning of period	24,118,037	22,076,749
Cash and cash equivalents, end of period	21,637,156	27,618,393
Supplemental disclosures of cash flow information:
Income taxes paid	$ 5,080	$ 2,743

Interim Financial Information	3 Months Ended
Interim Financial Information	Mar. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Interim Financial Information	1. Interim Financial Information Organization and Business MediciNova, Inc. (the “Company” or “MediciNova”) was incorporated in the state of Delaware in September 2000 and is a public company. The Company’s common stock is listed in both the U.S. and Japan and trades on The NASDAQ Global Market and the JASDAQ Market of the Tokyo Stock Exchange. MediciNova is a biopharmaceutical company focused on acquiring and developing novel, small molecule therapeutics for the treatment of serious diseases with unmet medical needs with a commercial focus on the U.S. market. The Company’s current strategy is to focus its development activities on MN-166 (ibudilast) for neurological disorders such as progressive multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS) and substance dependence (e.g., methamphetamine dependence, opioid dependence and alcohol dependence), and MN-001 (tipelukast) for fibrotic diseases such as nonalcoholic steatohepatitis (NASH) and idiopathic pulmonary fibrosis (IPF). The Company’s pipeline also includes MN-221 (bedoradrine) for the treatment of acute exacerbations of asthma and MN-029 (denibulin) for solid tumor cancers. Basis of Presentation The accompanying unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (GAAP) for interim financial information and with the instructions of the Securities and Exchange Commission (SEC) on Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and disclosures required by GAAP for complete financial statements. In the opinion of management, the consolidated financial statements include all adjustments necessary, which are of a normal and recurring nature, for the fair presentation of the Company’s financial position and of the results of operations and cash flows for the periods presented. The accompanying unaudited consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. These financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2016 included in the Company’s Annual Report on Form 10-K filed with the SEC. The results of operations for the interim period shown in this report are not necessarily indicative of the results that may be expected for any other interim period or for the full year. The balance sheet at December 31, 2016 has been derived from the audited financial statements at that date, but does not include all of the information and footnotes required by GAAP for complete financial statements. Research, Development and Patents Research and development costs are expensed in the period incurred. Research and development costs primarily consist of salaries and related expenses for personnel, facilities and depreciation, research and development supplies, licenses and outside services. Such research and development costs totaled $0.8 million and $1.0 million for the three months ended March 31, 2017 and 2016, respectively. Costs related to filing and pursuing patent applications are expensed as incurred, as recoverability of such expenditures is uncertain. The Company includes all external costs related to the filing of patents on developments in Research, Development and Patents expenses. Such patent-related expenses totaled $0.1 million for each of the three months ended March 31, 2017 and 2016. Use of Estimates The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and the accompanying notes. Actual results could differ from those estimates. Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) amended the existing accounting standards for revenue recognition. The amendments are based on the principle that revenue should be recognized to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for said goods or services. The Company is required to adopt the amendments beginning January 1, 2018. Early adoption is permitted as of January 1, 2017. The amendments may be applied retrospectively to each prior period presented or retrospectively with the cumulative effect recognized as of the date of initial application. The adoption of this statement is not expected to have a material impact on the Company’s consolidated financial statements. In February 2016, the FASB issued Accounting Standards Update (“ASU”) 2016-02, Leases, which introduces the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under previous guidance. The new standard establishes a right-of-use ("ROU") model that requires a lessee to record an ROU asset and a lease liability on the balance sheet for all leases with terms longer than 12 months. The new standard is effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years with early adoption permitted. We are evaluating the impact that the adoption of this standard will have on our financial statements. In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting, which simplifies several aspects of accounting for share-based payment transactions including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. The new standard is effective for fiscal years beginning after December 15, 2016 and interim periods within those fiscal years with early adoption permitted. The adoption of ASU 2016-09 in fiscal year 2017 had an immaterial effect on our financial statements. In January 2017, the FASB issued ASU 2017-04, Intangibles — Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment, which simplified the subsequent measurement of goodwill by eliminating Step 2 from the goodwill impairment test. The new standard is effective for annual and interim periods in fiscal years beginning after December 15, 2019. Early adoption is permitted after January 1, 2017. The adoption of this statement is not expected to have a material impact on the Company’s consolidated financial statements.

Revenue Recognition	3 Months Ended
Revenue Recognition	Mar. 31, 2017
Revenue Recognition [Abstract]
Revenue Recognition	2. Revenue Recognition Revenue Recognition Policy Revenues consist of milestone payments and research and development services. Milestone payments are recognized as revenue upon achievement of pre-defined scientific events, which require substantive effort, and for which achievement of the milestone was not readily assured at the inception of the agreement. Milestones that do not meet the criteria for accounting under the milestone method because the payments are solely contingent upon the performance of a third party are accounted for as contingent revenue. Research and development services are recognized as research costs are incurred over the period the services are performed. For all other revenue the Company recognizes revenues when all four of the following criteria are met: (1) persuasive evidence that an arrangement exists; (2) delivery of the products and/or services has occurred; (3) the selling price is fixed or determinable; and (4) collectability is reasonably assured. Kissei Pharmaceutical Co., Ltd In October 2011, the Company entered into an agreement with Kissei Pharmaceutical Co., Ltd., or Kissei, to perform research and development services relating to MN-221 in exchange for a non-refundable upfront payment of $2.5 million. Under the terms of the agreement, the Company is responsible for all costs to be incurred in the performance of these services. Certain of these research and development services were completed in 2013 and 2012, and the remaining services are expected to be delivered and completed at a future date. The Company assessed the deliverables in accordance with the authoritative guidance and concluded the existence of one deliverable, research and development services. As such, revenue is being recognized as the research and development services are performed. The amount received from Kissei, net of the amount recorded as revenue, is included on the balance sheet as long-term deferred revenue and will be recognized as revenue as the remaining services are performed. No services were performed and no revenue was recorded in the three months ended March 31, 2017 and 2016.

Fair Value Measurements

3 Months Ended

Mar. 31, 2017

Fair Value Disclosures [Abstract]

Fair Value Measurements

3. Fair Value Measurements

Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, a three-tier fair value hierarchy has been established, which prioritizes the inputs used in measuring fair value as follows:

Level 1:	Observable inputs such as quoted prices in active markets;

Level 2:	Inputs are quoted prices for similar items in active markets or quoted prices for identical or similar items in markets that are not active near the measurement date; and

Level 3:	Unobservable inputs due to little or no market data, which require the reporting entity to develop its own assumptions.

Cash and cash equivalents, including money market accountsof $662,064 and $661,287 measured at fair value as of March 31, 2017 and December 31, 2016, respectively, are classified within Level 1 of the fair value hierarchy.

Joint Venture	3 Months Ended
Joint Venture	Mar. 31, 2017
Equity Method Investments And Joint Ventures [Abstract]
Joint Venture	4. Joint Venture The Company entered into an agreement to form a joint venture company with Zhejiang Medicine Co., Ltd. and Beijing Medfron Medical Technologies Co., Ltd. (formerly Beijing Make-Friend Medicine Technology Co., Ltd.) effective September 27, 2011. The joint venture agreement provides for the joint venture company, Zhejiang Sunmy Bio-Medical Co., Ltd. (Zhejiang Sunmy), to develop and commercialize MN-221 in China and pursue additional compounds to develop. A sublicense agreement would be required under which Zhejiang Sunmy would license MN-221 from the Company and, as of the date of this filing, no such sublicense agreement has been entered into. In accordance with the joint venture agreement, in March 2012 the Company paid $680,000 for a 30% interest in Zhejiang Sunmy. The other parties to the joint venture agreement provided funding for their combined 70% interest. In December 2013, the Board of Directors of Zhejiang Sunmy agreed to amend the joint venture agreement to allow for the departure of Zhejiang Medicine Co., Ltd. subject to the approval of the government of the People’s Republic of China. In August 2014, the Chinese government approved the amendment to the joint venture agreement to allow for the departure of Zhejiang Medicine Co., Ltd. and for Beijing Medfron Medical Technologies Co., Ltd. and MediciNova to each have a 50% interest in Zhejiang Sunmy. No additional capital was contributed by either remaining party and the Company has no future funding obligations. Zhejiang Sunmy is a variable interest entity for which the Company is not the primary beneficiary as the Company does not have a majority of the board seats and does not have power to direct or significantly influence the actions of the entity. The activities of Zhejiang Sunmy are accounted for under the equity method whereby the Company absorbs any loss or income generated by Zhejiang Sunmy according to the Company’s percentage ownership. At March 31, 2017 and December 31, 2016, the investment is reflected as a long-term asset on the Company’s consolidated balance sheet which represents the investment and maximum loss exposure in Zhejiang Sunmy, net of the Company’s portion of any generated loss or income.

Stock-based Compensation

3 Months Ended

Mar. 31, 2017

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock-based Compensation

5. Stock-based Compensation

Stock Incentive Plans

In June 2013, the Company adopted the 2013 Equity Incentive Plan, or 2013 Plan, under which the Company may grant stock options, stock appreciation rights, restricted stock, restricted stock units and other awards to individuals who are then employees, officers, non-employee directors or consultants of the Company or its subsidiaries. The 2013 Plan is the successor to the Company’s Amended and Restated 2004 Stock Incentive Plan, or 2004 Plan. A total of 2,500,000 shares of common stock were initially reserved for issuance under the 2013 Plan, plus “returning shares” that may become available from time to time. “Returning shares” are shares that are subject to outstanding awards granted under the 2004 Plan that expire or terminate prior to exercise or settlement, are forfeited because of the failure to vest, are repurchased, or are withheld to satisfy tax withholding or purchase price obligations in connection with such awards. Although the Company no longer grants equity awards under the 2004 Plan, all outstanding stock awards granted under the 2004 Plan will continue to be subject to the terms and conditions as set forth in the agreements evidencing such stock awards and the terms of the 2004 Plan. As of March 31, 2017, 83,192 shares remain available for future grant under the 2013 Plan.

We occasionally issue employee performance-based stock options, the vesting of which is based on a determination made by our board of directors as to the achievement of certain corporate objectives at the end of the performance period. The grant date of such awards is the date on which our board of directors makes its determination. For periods preceding the grant date, the expense related to these awards is measured based on their fair value at each reporting date.

Stock Options

Options granted under the 2013 Plan and the 2004 Plan have terms of ten years from the date of grant and generally vest over a three or four year period. The exercise price of all options granted through March 31, 2017 and in 2016 was equal to the market value of the Company’s common stock on the date of grant.

A summary of stock option activity and related information as of March 31, 2017 is as follows:

	Number of Option Shares		Weighted Average Exercise Price
Outstanding at December 31, 2016		4,432,017	$	3.47
Granted		1,120,000	$	6.10
Exercised		—		—
Cancelled		—		—
Outstanding at March 31, 2017		5,552,017	$	4.00
Exercisable at March 31, 2017		4,177,422	$	3.45

No options were exercised during the three months ended March 31, 2017. During the three months ended March 31, 2016, there were 129,819 options exercised, from which gross proceeds of $681,136 were received.

Employee Stock Purchase Plan

Under the Company’s 2007 Employee Stock Purchase Plan, or ESPP, 300,000 shares of common stock were originally reserved for issuance. In addition, the shares reserved automatically increase each year by a number equal to the lesser of: (i) 15,000 shares; (ii) 1% of the outstanding shares of common stock on the last day of the immediately preceding fiscal year; or (iii) such lesser amount as determined by the Board. The ESPP permits full-time employees to purchase common stock through payroll deductions (which cannot exceed 15% of each employee’s compensation) at the lower of 85% of fair market value at the beginning of the offering period or the end of each six-month offering period. The ESPP is considered a compensatory plan and the Company records compensation expense included in the Company’s statement of operations.

For the three months ended March 31, 2017, an aggregate of 12,775 shares were issued under the ESPP. As of March 31, 2017, there are 186,350 shares available for future issuance under the ESPP.

Compensation Expense

Stock-based compensation expense for stock option awards and ESPP shares are reflected in total operating expenses for each respective year. For the three months ended March 31, 2017 and 2016 stock-based compensation expense related to stock options and the ESPP was $1.2 million and $1.4 million, respectively.

The Company uses the Black-Scholes valuation model for determining the estimated fair value for stock-based awards granted to employees. The following table provides the assumptions used in the Black-Scholes valuation model used to estimate the fair value of options granted during the three months ended March 31, 2017 and 2016 and to estimate the fair value of performance-based stock options as of March 31, 2017.


	March 31, 2017		March 31, 2016
Stock Option assumptions:
Risk-free interest rate	1.93 - 2.08%			1.61%
Expected volatility of common stock	67.77 - 72.13%			78.3%
Dividend yield		0%		0%
Expected term (in years)	4.47 - 5.30			5.6

As of March 31, 2017, there was $4.1 million of unamortized compensation cost related to unvested stock option awards which is expected to be recognized over a remaining weighted-average vesting period of 0.45 years, on a straight-line basis.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References + Details

Stockholders' Equity

3 Months Ended

Mar. 31, 2017

Equity [Abstract]

Stockholders' Equity

6. Stockholders’ Equity

At-The-Market Issuance Sales Agreements

On May 22, 2015, the Company entered into an at-the-market issuance sales agreement with MLV & Co. LLC, or MLV, pursuant to which the Company may sell common stock through MLV from time to time up to an aggregate offering price of $30.0 million. Sales of the Company’s common stock through MLV, if any, will be made by any method that is deemed to be an “at-the-market” equity offering as defined in Rule 415 promulgated under the Securities Act of 1933, as amended, including sales made directly on NASDAQ, on any other existing trading market for the common stock or to or through a market maker. MLV may also sell the common stock in privately negotiated transactions, subject to the Company’s prior approval. The Company agreed to pay MLV an aggregate commission rate of up to 4.0% of the gross proceeds of any common stock sold under this agreement. Proceeds from sales of common stock will depend on the number of shares of common stock sold to MLV and the per share purchase price of each transaction.

On September 16, 2016, the Company entered into an amendment No.1 to the original sales agreement with MLV to also include FBR Capital Markets & Co. as a sales agent. The Company is not obligated to make any sales of common stock under the sales agreement and may terminate the sales agreement at any time upon written notice.

For the three months ended March 31, 2017, the Company generated gross proceeds of $24,800 and incurred issuance costs of $23,668 under this agreement on sales of 4,000 shares of the Company’s common stock at $6.20 per share. No shares of common stock were sold in the three months ended March 31, 2016.

On September 26, 2011, the Company issued and sold to Kissei 220,000 shares of Series B Convertible Preferred Stock. Each share of the Series B Preferred stock was convertible into shares of common stock at a conversion rate of 1:10 at the option of the holder. On June 15, 2016, Kissei elected to convert all 220,000 preferred shares into 2,200,000 shares of common stock.

Common Stock Warrants

No warrants were exercised during the three months ended March 31, 2017. During the three months ended March 31, 2016, warrants to purchase 2,131,700 shares of the Company’s common stock were exercised for gross proceeds of $7.6 million. On March 29, 2016, warrants to purchase 207,600 shares of the Company’s common stock expired unexercised.

As of March 31, 2017, the Company had the following warrants outstanding:

•

198,020 common stock warrants at an exercise price of $6.06 per share, which expire on May 10, 2017;

•

750,000 common stock warrants at an exercise price of $3.15 per share, which expire on May 9, 2018; and

•

119,047 common stock warrants at an exercise price of $3.38 per share, which expire on May 9, 2018.

- Definition

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

+ References

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+ Details

Net Loss Per Share

3 Months Ended

Mar. 31, 2017

Earnings Per Share [Abstract]

Net Loss Per Share

7. Net Loss Per Share

The Company computes basic net loss per share using the weighted average number of common shares outstanding during the period. Diluted net income per share is based upon the weighted average number of common shares and potentially dilutive securities (common share equivalents) outstanding during the period. Common share equivalents outstanding, determined using the treasury stock method, are comprised of shares that may be issued under the Company’s stock option agreements, and warrants. Common share equivalents are excluded from the diluted net loss per share calculation if their effect is anti-dilutive.

The following potentially dilutive outstanding securities were excluded from diluted net loss per common share because of their anti-dilutive effect:

	March 31,
	2017		2016
Convertible preferred stock, as converted		—		2,200,000
Stock options		5,552,017		5,064,350
Warrants		1,067,067		1,067,067
Total		6,619,084		8,331,417

Related Party Transactions	3 Months Ended
Related Party Transactions	Mar. 31, 2017
Related Party Transactions [Abstract]
Related Party Transactions	8. Related Party Transactions On October 13, 2011, the Company entered into a services agreement with Kissei to perform two separate studies relating to MN-221 in exchange for $2.5 million paid to the Company in October 2011. The Company is responsible for all costs to be incurred in the performance of these studies. The amount received from Kissei, net of the amount recorded as revenue through March 31, 2017, is included on the balance sheet at March 31, 2017 as long-term deferred revenue and will be recognized as revenue in future periods upon the Company’s performance of the remaining services. No services were performed and no revenues related to this services agreements were recognized during three months ended March 31, 2017 and 2016.

Interim Financial Information (Policies)	3 Months Ended
Interim Financial Information (Policies)	Mar. 31, 2017
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (GAAP) for interim financial information and with the instructions of the Securities and Exchange Commission (SEC) on Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and disclosures required by GAAP for complete financial statements. In the opinion of management, the consolidated financial statements include all adjustments necessary, which are of a normal and recurring nature, for the fair presentation of the Company’s financial position and of the results of operations and cash flows for the periods presented. The accompanying unaudited consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. These financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2016 included in the Company’s Annual Report on Form 10-K filed with the SEC. The results of operations for the interim period shown in this report are not necessarily indicative of the results that may be expected for any other interim period or for the full year. The balance sheet at December 31, 2016 has been derived from the audited financial statements at that date, but does not include all of the information and footnotes required by GAAP for complete financial statements.
Research, Development and Patents	Research, Development and Patents Research and development costs are expensed in the period incurred. Research and development costs primarily consist of salaries and related expenses for personnel, facilities and depreciation, research and development supplies, licenses and outside services. Such research and development costs totaled $0.8 million and $1.0 million for the three months ended March 31, 2017 and 2016, respectively. Costs related to filing and pursuing patent applications are expensed as incurred, as recoverability of such expenditures is uncertain. The Company includes all external costs related to the filing of patents on developments in Research, Development and Patents expenses. Such patent-related expenses totaled $0.1 million for each of the three months ended March 31, 2017 and 2016.
Use of Estimates	Use of Estimates The preparation of the consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and the accompanying notes. Actual results could differ from those estimates.
Recently Issued Accounting Pronouncements	Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) amended the existing accounting standards for revenue recognition. The amendments are based on the principle that revenue should be recognized to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for said goods or services. The Company is required to adopt the amendments beginning January 1, 2018. Early adoption is permitted as of January 1, 2017. The amendments may be applied retrospectively to each prior period presented or retrospectively with the cumulative effect recognized as of the date of initial application. The adoption of this statement is not expected to have a material impact on the Company’s consolidated financial statements. In February 2016, the FASB issued Accounting Standards Update (“ASU”) 2016-02, Leases, which introduces the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under previous guidance. The new standard establishes a right-of-use ("ROU") model that requires a lessee to record an ROU asset and a lease liability on the balance sheet for all leases with terms longer than 12 months. The new standard is effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years with early adoption permitted. We are evaluating the impact that the adoption of this standard will have on our financial statements. In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting, which simplifies several aspects of accounting for share-based payment transactions including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. The new standard is effective for fiscal years beginning after December 15, 2016 and interim periods within those fiscal years with early adoption permitted. The adoption of ASU 2016-09 in fiscal year 2017 had an immaterial effect on our financial statements. In January 2017, the FASB issued ASU 2017-04, Intangibles — Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment, which simplified the subsequent measurement of goodwill by eliminating Step 2 from the goodwill impairment test. The new standard is effective for annual and interim periods in fiscal years beginning after December 15, 2019. Early adoption is permitted after January 1, 2017. The adoption of this statement is not expected to have a material impact on the Company’s consolidated financial statements.
Revenue Recognition Policy	Revenue Recognition Policy Revenues consist of milestone payments and research and development services. Milestone payments are recognized as revenue upon achievement of pre-defined scientific events, which require substantive effort, and for which achievement of the milestone was not readily assured at the inception of the agreement. Milestones that do not meet the criteria for accounting under the milestone method because the payments are solely contingent upon the performance of a third party are accounted for as contingent revenue. Research and development services are recognized as research costs are incurred over the period the services are performed. For all other revenue the Company recognizes revenues when all four of the following criteria are met: (1) persuasive evidence that an arrangement exists; (2) delivery of the products and/or services has occurred; (3) the selling price is fixed or determinable; and (4) collectability is reasonably assured.

Stock-based Compensation (Tables)

3 Months Ended

Mar. 31, 2017

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Stock Option Activity and Related Information

A summary of stock option activity and related information as of March 31, 2017 is as follows:

	Number of Option Shares		Weighted Average Exercise Price
Outstanding at December 31, 2016		4,432,017	$	3.47
Granted		1,120,000	$	6.10
Exercised		—		—
Cancelled		—		—
Outstanding at March 31, 2017		5,552,017	$	4.00
Exercisable at March 31, 2017		4,177,422	$	3.45

Schedule of Assumptions Used in Estimating Fair Value of Options Granted

The following table provides the assumptions used in the Black-Scholes valuation model used to estimate the fair value of options granted during the three months ended March 31, 2017 and 2016 and to estimate the fair value of performance-based stock options as of March 31, 2017.


	March 31, 2017		March 31, 2016
Stock Option assumptions:
Risk-free interest rate	1.93 - 2.08%			1.61%
Expected volatility of common stock	67.77 - 72.13%			78.3%
Dividend yield		0%		0%
Expected term (in years)	4.47 - 5.30			5.6

Net Loss Per Share (Tables)

3 Months Ended

Mar. 31, 2017

Earnings Per Share [Abstract]

Securities Excluded from Diluted Net Loss Per Common Share

The following potentially dilutive outstanding securities were excluded from diluted net loss per common share because of their anti-dilutive effect:

	March 31,
	2017		2016
Convertible preferred stock, as converted		—		2,200,000
Stock options		5,552,017		5,064,350
Warrants		1,067,067		1,067,067
Total		6,619,084		8,331,417

Interim Financial Information - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Research and development	$ 0.8	$ 1.0
Patent-related expenses	$ 0.1	$ 0.1

Revenue Recognition - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Oct. 31, 2011
Revenue Recognition Milestone Method [Line Items]
Deferred revenue related to research and development services	$ 1,694,163		$ 1,694,163
Kissei Pharmaceutical Co., Ltd
Revenue Recognition Milestone Method [Line Items]
Deferred revenue related to research and development services				$ 2,500,000
Revenue relating to research and development services	$ 0	$ 0

- Definition

The noncurrent portion of deferred revenue amount as of balance sheet date. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized, and is not expected to be recognized in the next twelve months. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References + Details

Fair Value Measurements - Additional Information (Detail) - USD ($)	Mar. 31, 2017	Dec. 31, 2016
Fair Value Measurements Using Level 1 \| Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents fair value	$ 662,064	$ 661,287

Joint Venture - Additional Information (Detail) - Zhejiang Sunmy Bio Medical Co Ltd - USD ($)	1 Months Ended
	Aug. 31, 2014	Mar. 31, 2012
Schedule Of Equity Method Investments [Line Items]
Investment in joint venture	$ 0	$ 680,000
Investment in joint venture, percentage	50.00%	30.00%
Other parties investment in joint venture, percentage		70.00%
Future funding obligation	$ 0
Beijing Medfron Medical Technologies Co Ltd
Schedule Of Equity Method Investments [Line Items]
Investment in joint venture	$ 0
Investment in joint venture, percentage	50.00%

Stock-based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Jun. 30, 2013	Dec. 31, 2007
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options exercised	0	129,819
Gross proceed from stock options exercised		$ 681,136
Shares reserved, description	shares reserved automatically increase each year by a number equal to the lesser of: (i) 15,000 shares; (ii) 1% of the outstanding shares of common stock on the last day of the immediately preceding fiscal year; or (iii) such lesser amount as determined by the Board.
Employee stock purchase plan offering period	6 months
Shares issued under ESPP	12,775
Stock-based compensation expense	$ 1,168,155	$ 1,439,149
Unamortized compensation cost	$ 4,100,000
2007 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	186,350			300,000
Percentage of employee compensation for purchase of common stock under ESPP	15.00%
Common stock fair market value, percentage	85.00%
Maximum \| 2007 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in shares reserved for issuance	15,000
Increase in shares reserved for issuance as percentage of outstanding shares	1.00%
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized compensation cost, vesting period	5 months 12 days
2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance			2,500,000
Shares available for future grant	83,192
2013 Plan \| Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted expiration term	10 years
2013 Plan \| Stock Option \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option, vesting period	3 years
2013 Plan \| Stock Option \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option, vesting period	4 years
2004 Plan \| Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted expiration term	10 years
2004 Plan \| Stock Option \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option, vesting period	3 years
2004 Plan \| Stock Option \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option, vesting period	4 years

Summary of Stock Option Activity and Related Information (Detail) - $ / shares	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Number of Option Shares
Stock Options, Beginning Balance	4,432,017
Stock Options, Granted	1,120,000
Stock Options, Exercised	0	(129,819)
Stock Options, Ending Balance	5,552,017
Stock Options, Exercisable at March 31, 2017	4,177,422
Weighted Average Exercise Price, Beginning Balance	$ 3.47
Weighted Average Exercise Price, Granted	6.10
Weighted Average Exercise Price, Ending Balance	4.00
Weighted Average Exercise Price, Exercisable at March 31, 2017	$ 3.45

Schedule of Assumptions Used in Estimating Fair Value of Options Granted (Detail) - Stock Option	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Stock Option assumptions:
Risk-free interest rate		1.61%
Expected volatility of common stock		78.30%
Dividend yield	0.00%	0.00%
Expected term (in years)		5 years 7 months 6 days
Minimum
Stock Option assumptions:
Risk-free interest rate	1.93%
Expected volatility of common stock	67.77%
Expected term (in years)	4 years 5 months 19 days
Maximum
Stock Option assumptions:
Risk-free interest rate	2.08%
Expected volatility of common stock	72.13%
Expected term (in years)	5 years 3 months 18 days

Stockholders' Equity - Additional Information (Detail) - USD ($)			3 Months Ended
	May 22, 2015	Sep. 26, 2011	Mar. 31, 2017	Mar. 31, 2016	Jun. 15, 2016	Mar. 29, 2016
Series B Convertible Preferred Stock \| Kissei Pharmaceutical Co., Ltd
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of common stock, net of offering costs (in shares)		220,000
Preferred stock, conversion basis			Each share of the Series B Preferred stock was convertible into shares of common stock at a conversion rate of 1:10 at the option of the holder
Conversion rate of preferred stock		10.00%
Warrant One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants, Outstanding			198,020
Common share exercise price			$ 6.06
Warrant termination date			May 10, 2017
Warrant Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants, Outstanding			750,000
Common share exercise price			$ 3.15
Warrant termination date			May 09, 2018
Warrant Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Warrants, Outstanding			119,047
Common share exercise price			$ 3.38
Warrant termination date			May 09, 2018
MLV \| At-the-market issuance sales agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sales commission as a percentage of gross proceeds	4.00%
Stock purchase agreement, gross proceeds			$ 24,800
Payments of Stock Issuance Costs			$ 23,668
Issuance of common stock, net of offering costs (in shares)			4,000	0
MLV \| Maximum \| At-the-market issuance sales agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock purchase agreement, aggregate amount of common stock agreed to be purchased	$ 30,000,000
Common stock \| Series B Convertible Preferred Stock \| Kissei Pharmaceutical Co., Ltd
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock issued upon conversion of preferred stock					2,200,000
Common stock \| MLV \| At-the-market issuance sales agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares purchase & equity issuance, per share amount			$ 6.20
Warrants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise of warrants			0	2,131,700
Proceeds from warrant exercises				$ 7,600,000
Warrants expiring unexercised						207,600

Securities Excluded from Diluted Net Loss Per Common Share (Detail) - shares	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total	6,619,084	8,331,417
Convertible preferred stock, as converted
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total		2,200,000
Stock Option
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total	5,552,017	5,064,350
Warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Total	1,067,067	1,067,067

Related Party Transactions - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Oct. 31, 2011
Related Party Transaction [Line Items]
Deferred revenue related to research and development services	$ 1,694,163		$ 1,694,163
Kissei Pharmaceutical Co., Ltd
Related Party Transaction [Line Items]
Deferred revenue related to research and development services				$ 2,500,000
Revenue relating to research and development services	$ 0	$ 0

- Definition

+ References + Details