View Filing Data

Print Document View Excel Document

Document And Entity Information - shares	6 Months Ended
Document And Entity Information - shares	Jun. 30, 2017	Aug. 03, 2017
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q2
Entity Registrant Name	ASSEMBLY BIOSCIENCES, INC.
Entity Central Index Key	0001426800
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Trading Symbol	ASMB
Entity Common Stock, Shares Outstanding		17,364,439

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Current assets
Cash and cash equivalents	$ 39,452,737	$ 28,575,085
Marketable securities, at fair value	36,123,684	24,388,403
Accounts receivable	1,113,759	0
Prepaid expenses and other current assets	978,356	611,176
Total current assets	77,668,536	53,574,664
Long-term assets
Marketable securities, at fair value	3,008,840	2,435,753
Property, plant and equipment, net	131,857	214,687
Security deposits	327,250	255,366
Intangible assets	29,000,000	29,000,000
Goodwill	12,638,136	12,638,136
Total long-term assets	45,106,083	44,543,942
Total assets	122,774,619	98,118,606
Current liabilities
Accounts payable	687,908	2,368,131
Accrued expenses	6,305,547	4,752,823
Deferred revenue - short-term	4,995,894	0
Total current liabilities	11,989,349	7,120,954
Long-term liabilities
Deferred tax liabilities	11,176,072	11,119,651
Deferred revenue - long-term	43,074,186	0
Total long-term liabilities	54,250,258	11,119,651
Total liabilities	66,239,607	18,240,605
Commitments and contingencies
Stockholders' equity
Preferred stock, $0.001 par value; 5,000,000 shares authorized; 0 shares issued and outstanding	0	0
Common stock, $0.001 par value; 50,000,000 shares authorized; 17,360,689 and 17,246,754 shares issued and outstanding as of June 30, 2017 and December 31, 2016, respectively	17,361	17,247
Additional paid-in capital	292,672,842	288,688,990
Accumulated other comprehensive loss	(398,267)	(600,769)
Accumulated deficit	(235,756,924)	(208,227,467)
Total stockholders' equity	56,535,012	79,878,001
Total liabilities and stockholders' equity	$ 122,774,619	$ 98,118,606

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Jun. 30, 2017	Dec. 31, 2016
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	17,360,689	17,246,754
Common stock, shares outstanding	17,360,689	17,246,754

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Collaboration revenue	$ 2,359,311	$ 0	$ 3,043,680	$ 0
Operating expenses:
Research and development	12,125,021	7,519,031	22,698,760	15,637,607
General and administrative	3,801,541	2,935,099	7,842,000	6,093,675
Total operating expenses	15,926,562	10,454,130	30,540,760	21,731,282
Loss from operations	(13,567,251)	(10,454,130)	(27,497,080)	(21,731,282)
Other income (expenses)
Interest and other income	239,858	444,605	376,342	935,026
Realized loss from marketable securities	(340,984)	(142,675)	(478,232)	(344,502)
Total other income	(101,126)	301,930	(101,890)	590,524
Loss before income taxes	(13,668,377)	(10,152,200)	(27,598,970)	(21,140,758)
Income tax benefit	69,513	0	69,513	0
Net loss	(13,598,864)	(10,152,200)	(27,529,457)	(21,140,758)
Other comprehensive (loss) income
Unrealized loss recognized in accumulated other comprehensive loss before reclassification, net of tax benefit of $57,437, $0, $57,437 and $0, respectively	(31,203)	(232,542)	(92,359)	(362,279)
Reclassification adjustment of unrealized loss included in net loss, net of tax expense of $183,371, $0, $183,371 and $0, respectively	157,613	142,675	294,861	344,502
Comprehensive loss	$ (13,472,454)	$ (10,242,067)	$ (27,326,955)	$ (21,158,535)
Net loss per share, basic and diluted	$ (0.78)	$ (0.59)	$ (1.59)	$ (1.23)
Weighted average common shares outstanding, basic and diluted	17,342,623	17,225,660	17,305,657	17,225,661

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Parenthetical) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Unrealized loss recognized in accumulated other comprehensive loss before reclassification, net of tax benefit	$ 57,437	$ 0	$ 57,437	$ 0
Reclassification adjustment of unrealized loss included in net loss, net of tax expense	$ 183,371	$ 0	$ 183,371	$ 0

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash flows from operating activities
Net loss	$ (27,529,457)	$ (21,140,758)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	82,830	37,093
Stock-based compensation	3,235,908	2,977,993
Realized loss from marketable securities	478,232	344,502
Deferred income tax benefit	(69,513)	0
Changes in operating assets and liabilities:
Accounts receivable	(1,113,759)	0
Prepaid expenses and other current assets	(367,180)	147,643
Accounts payable	(1,680,223)	1,050,224
Accrued expenses	1,552,724	591,742
Deferred revenue	48,070,080	0
Security deposits	(71,884)	13,460
Net cash provided by (used in) operating activities	22,587,758	(15,978,100)
Cash flows from investing activities
Purchases of fixed assets	0	(2,163)
Purchases of marketable securities	(32,591,164)	(7,951,257)
Redemptions of marketable securities	20,133,000	17,165,332
Net cash (used in) provided by investing activities	(12,458,164)	9,211,912
Cash flows from financing activities
Proceeds from the exercise of stock options	748,058	0
Net cash provided by financing activities	748,058	0
Net increase (decrease) in cash and cash equivalents	10,877,652	(6,766,188)
Cash and cash equivalents at the beginning of the period	28,575,085	27,107,526
Cash and cash equivalents at the end of the period	39,452,737	20,341,338
Supplemental disclosure of cash flow information:
Change in unrealized gain (loss) on marketable securities available-for-sale, before tax expense	$ 328,436	$ (17,777)

CONDENSED CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY - 6 months ended Jun. 30, 2017 - USD ($)	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Accumulated Deficit [Member]
Balance at Dec. 31, 2016	$ 79,878,001	$ 17,247	$ 288,688,990	$ (600,769)	$ (208,227,467)
Balance (in Shares) at Dec. 31, 2016		17,246,754
Proceeds from the exercise of stock options	748,058	$ 114	747,944	0	0
Proceeds from the exercise of stock options (in shares)		113,935
Change in unrealized gain on marketable securities, net of income tax expense of $125,934	202,502	$ 0	0	202,502	0
Stock-based compensation	3,235,908	0	3,235,908	0	0
Net loss	(27,529,457)	0	0	0	(27,529,457)
Balance at Jun. 30, 2017	$ 56,535,012	$ 17,361	$ 292,672,842	$ (398,267)	$ (235,756,924)
Balance (in Shares) at Jun. 30, 2017		17,360,689

CONDENSED CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical)	6 Months Ended
	Jun. 30, 2017 USD ($)
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax	$ 125,934

Nature of Business

6 Months Ended

Jun. 30, 2017

Organization, Business and Basis Of Presentation [Abstract]

Nature of Business

Note 1 - Nature of Business

Overview

Assembly Biosciences, Inc. (Assembly or the Company) is a clinical stage biotechnology company advancing two innovative platform programs: a new class of oral therapeutics for the treatment of hepatitis B virus (HBV) infection and a novel class of oral synthetic live biotherapeutics, which are designed to restore health to a dysbiotic microbiome. The Company’s HBV-cure program is aimed at increasing the current low cure rate for patients with HBV and is pursuing multiple drug candidates that inhibit multiple steps of the HBV lifecycle. Assembly has discovered several novel Core protein Allosteric Modulators (CpAMs), which are small molecules that directly target and allosterically modulate the HBV core (HBc) protein. The lead product candidate from this program, ABI-H0731, has completed a Phase 1a human clinical trial, and the Phase 1b/2a portion of the clinical trial commenced in the second quarter of 2017. The Company’s Microbiome program consists of a fully integrated platform that includes a disease targeted strain identification and selection process, methods for strain isolation and growth under current Good Manufacturing Practice(cGMP) conditions, and a patent pending delivery system that the Company calls GEMICEL ®, which allows for targeted oral delivery of live biologic and conventional therapies to the lower gastrointestinal (GI) tract. The lead product candidate from this platform, ABI-M101, is in development for the treatment of clostridium difficile infections (CDI). Using its microbiome platform, the Company is developing additional product candidates for other disease indications, which the Company will develop either internally or in collaboration with partners.

On January 6, 2017, the Company entered into a Research, Development, Collaboration and License Agreement (the Collaboration Agreement) with Allergan Pharmaceuticals International Limited (Allergan) to develop and commercialize select microbiome gastrointestinal programs. Pursuant to the terms of the Collaboration Agreement, in connection with the closing of the transaction on February 10, 2017, Allergan paid the Company an upfront payment of $50 million. Additionally, the Company is eligible to receive up to approximately $630 million in payments related to seven development milestones and up to approximately $2.15 billion in payments related to 12 commercial development and sales milestones in connection with the successful development and commercialization of licensed compounds for up to six different indications (see Note 7). Allergan and the Company have agreed to share development costs up to an aggregate of $75 million through proof-of-concept (POC) studies on a ⅔, ⅓ basis, respectively, and Allergan has agreed to assume all post-POC development costs. Additionally, the Company has an option to co-promote the licensed programs in the United States and China, subject to certain conditions set forth in the Collaboration Agreement.

Liquidity

The Company has not derived any revenue from product sales to date and currently has no approved products. Once a product has been developed, it will need to be approved for sale by the U.S. Food and Drug Administration (FDA) or an applicable foreign regulatory agency. Since inception, the Company’s operations have been financed primarily through the sale of equity securities, the proceeds from the exercise of warrants and stock options, the issuance of debt and an up-front payment related to the Collaboration Agreement. The Company has incurred losses from operations and negative cash flows from operating activities since inception and expects to continue to incur substantial losses for the next several years as it continues its product development efforts. Management believes the Company currently has sufficient funds to meet its operating requirements for at least the next twelve months. If the Company cannot generate significant cash from its operations, it intends to obtain any additional funding it requires through strategic relationships, public or private equity or debt financings, grants or other arrangements. The Company cannot assure such funding will be available on reasonable terms, if at all.

If the Company is unable to generate enough revenue from the Collaboration Agreement when needed or to secure additional sources of funding and receive related full and timely collections of amounts due, it may be necessary to significantly reduce the current rate of spending through reductions in staff and delaying, scaling back, or stopping certain research and development programs, including more costly clinical trials.

Summary of Significant Accounting Policies and Recent Accounting Pronouncements

6 Months Ended

Jun. 30, 2017

Accounting Policies [Abstract]

Summary of Significant Accounting Policies and Recent Accounting Pronouncements

Note 2 - Summary of Significant Accounting Policies and Recent Accounting Pronouncements

Basis of Presentation

The accompanying condensed consolidated interim financial statements include the accounts of the Company and its subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.

The accompanying condensed consolidated financial statements have been prepared in accordance with the accounting principles generally accepted in the United States of America (U.S. GAAP) for interim financial information and pursuant to the instructions to Form 10-Q and Rule 10-01 of Regulation S-X of the U.S. Securities and Exchange Commission (SEC) and on the same basis as the Company prepares its annual audited consolidated financial statements. The condensed consolidated balance sheet at June 30, 2017, condensed consolidated statements of operations and comprehensive loss for the three and six months ended June 30, 2017 and 2016, condensed consolidated statements of cash flows for the six months ended June 30, 2017 and 2016, and condensed consolidated statement of changes in stockholders’ equity for the six months ended June 30, 2017 are unaudited, but include all adjustments, consisting only of normal recurring adjustments, that the Company considers necessary for a fair presentation of the financial position, operating results and cash flows for the periods presented. The results for the three and six months ended June 30, 2017 are not necessarily indicative of results to be expected for the year ending December 31, 2017 or for any future interim period. The consolidated balance sheet at December 31, 2016 has been derived from audited financial statements; however, it does not include all of the information and notes required by U.S. GAAP for complete financial statements. The accompanying condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements for the year ended December 31, 2016, and notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2016 filed with the SEC on March 2, 2017 (the 2016 Annual Report).

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that may affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.

Significant estimates inherent in the preparation of the accompanying financial statements include recoverability and useful lives (indefinite or finite) of intangible assets, assessment of impairment of goodwill, and the fair value of stock options and warrants granted to employees, consultants, directors, investors, licensors, placement agents and underwriters. In addition, with the Company entering into the Collaboration Agreement, the Company believes its condensed consolidated financial statements are also impacted by the following accounting estimates and judgments: (i) identifying deliverables under collaboration agreements involving multiple elements and determining whether such deliverables are separable from other aspects of the contractual relationship; (ii) estimating the selling price of deliverables for the purpose of allocating arrangement consideration for revenue recognition; and (iii) estimating the periods over which the allocated consideration for deliverables is recognized.

The Company’s estimates could be affected by external conditions, including those unique to the Company and general economic conditions. It is reasonably possible that these external factors could have an effect on the Company’s estimates and could cause actual results to differ from those estimates and assumptions.

Significant Accounting Policies

There have been no material changes in the Company’s significant accounting policies to those previously disclosed in the 2016 Annual Report other than the adoption of the following revenue recognition policy.

Revenue Recognition

The Company recognizes revenue when each of the following four criteria is met: (i) persuasive evidence of an arrangement exists; (ii) products are delivered or as services are rendered; (iii) the sales price is fixed or determinable; and (iv) collectability is reasonably assured.

The Company recognizes revenue under the Collaboration Agreement based on the relevant accounting literature. Under this guidance, multiple elements or deliverables may include (i) grants of licenses, or options to obtain licenses, to intellectual property, (ii) research and development services, (iii) participation on joint research and/or joint development committees, and/or (iv) manufacturing or supply services. The payments entities may receive under these arrangements typically include one or more of the following: non-refundable, upfront license fees; option exercise fees; funding of research and/or development efforts; amounts due upon the achievement of specified objectives; and/or royalties on future product sales.

Multiple-element arrangements require the separability of deliverables included in an arrangement into different units of accounting and the allocation of arrangement consideration to the units of accounting. The evaluation of multiple-element arrangements requires management to make judgments about (i) the identification of deliverables, (ii) whether such deliverables are separable from the other aspects of the contractual relationship, (iii) the estimated selling price of each deliverable, and (iv) the expected period of performance for each deliverable.

To determine the units of accounting under a multiple-element arrangement, management evaluates certain separation criteria, including whether the deliverables have stand-alone value, based on the relevant facts and circumstances for each arrangement. Management then estimates the selling price for each unit of accounting and allocates the arrangement consideration to each unit using the relative selling price method. The relative selling price for each deliverable is determined using vendor specific objective evidence (VSOE), of selling price or third-party evidence of selling price if VSOE does not exist. If neither VSOE nor third-party evidence of selling price exists, we use our best estimate of the selling price for the deliverable. The allocated consideration for each unit of accounting is recognized based on the method most appropriate for that unit of account and in accordance with the revenue recognition criteria detailed above.

If there are deliverables in an arrangement that are not separable from other aspects of the contractual relationship, they are treated as a combined unit of accounting, with the allocated revenue for the combined unit recognized in a manner consistent with the revenue recognition applicable to the final deliverable in the combined unit. Payments received prior to satisfying the relevant revenue recognition criteria are recorded as deferred revenue in the accompanying balance sheets and recognized as revenue when the related revenue recognition criteria are met.

The Collaboration Agreement provides for non-refundable milestone payments. The Company recognizes revenue that is contingent upon the achievement of a substantive milestone in its entirety in the period in which the milestone is achieved. A milestone is considered substantive when the consideration payable to the Company for such milestone (i) is consistent with the Company’s performance necessary to achieve the milestone or the increase in value to the collaboration resulting from the Company’s performance, (ii) relates solely to the Company’s past performance and (iii) is reasonable relative to all of the other deliverables and payments within the arrangement. In making this assessment, the Company considers all facts and circumstances relevant to the arrangement, including factors such as the scientific, regulatory, commercial and other risks that must be overcome to achieve the milestone, the level of effort and investment required to achieve the milestone and whether any portion of the milestone consideration is related to future performance or deliverables.

The Collaboration Agreement provides Allergan with options to license additional intellectual property rights, or purchase additional research, development, or supply services. The Company concluded that these were "substantive options" under the multiple-element arrangement guidance, and accordingly, associated fees have not been considered in allocating contract consideration among deliverables with stand-alone value. If Allergan exercises one or more of these options, the associated revenue would be recognized using the method most appropriate for the particular deliverable.

The Company will periodically review the estimated performance periods under the Collaboration Agreement, which provides for non-refundable upfront payments and fees. The Company will adjust the periods over which revenue should be recognized when appropriate to reflect changes in assumptions relating to the estimated performance periods. The Company could accelerate revenue recognition in the event of early termination of programs or if the Company’s expectations change. Alternatively, the Company could decelerate revenue recognition if programs are extended or delayed. While such changes to the Company’s estimates have no impact on the Company’s reported cash flows, the amount of revenue recorded in future periods could be materially impacted.

The Company records revenues related to the reimbursement of costs incurred under the Collaboration Agreement where the Company acts as a principal, controls the research and development activities and bears credit risk. Under the Collaboration Agreement, the Company is reimbursed for associated out-of-pocket costs. The gross amount of these pass-through reimbursed costs is reported as revenue in the accompanying statements of operations, while the actual expenses for which the Company is reimbursed are reflected as research and development costs. The Company has also accounted for the milestone payments under ASC 605 Revenue Recognition - Milestone Method. See Note 7 for further information.

Loss per Share of Common Stock

Basic net loss per share of common stock excludes dilution and is computed by dividing net loss by the weighted average number of shares of common stock outstanding during the period. Diluted net loss per share of common stock reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in the earnings of the entity unless inclusion of such shares would be anti-dilutive. Since the Company has only incurred losses, basic and diluted net loss per share is the same. Securities that could potentially result in diluted loss per share in the future that were not included in the computation of diluted loss per share at June 30, 2017 and 2016 are as follows:

	Six Months Ended June 30,
	2017		2016
Warrants to purchase common stock		16,909		16,909
Options to purchase common stock		4,837,464		4,097,952
Total		4,854,373		4,114,861

Adoption of Recent Accounting Pronouncements

In March 2016, the Financial Accounting Standards Board (the FASB) issued Accounting Standards Update (ASU) 2016-09, Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting. Under ASU 2016-09, companies will no longer record excess tax benefits and certain tax deficiencies in additional paid-in capital (APIC). Instead, they will record all excess tax benefits and tax deficiencies as income tax expense or benefit in the income statement and the APIC pools will be eliminated. In addition, ASU 2016-09 eliminates the requirement that excess tax benefits be realized before companies can recognize them. ASU 2016-09 also requires companies to present excess tax benefits as an operating activity on the statement of cash flows rather than as a financing activity. Furthermore, ASU 2016-09 will increase the amount an employer can withhold to cover income taxes on awards and still qualify for the exception to liability classification for shares used to satisfy the employer’s statutory income tax withholding obligation. An employer with a statutory income tax withholding obligation will now be allowed to withhold shares with a fair value up to the amount of taxes owed using the maximum statutory tax rate in the employee’s applicable jurisdiction(s). ASU 2016-09 requires a company to classify the cash paid to a tax authority when shares are withheld to satisfy its statutory income tax withholding obligation as a financing activity on the statement of cash flows. Under current GAAP, it is not specified how these cash flows should be classified. In addition, companies will now have to elect whether to account for forfeitures on share-based payments by (1) recognizing forfeitures of awards as they occur or (2) estimating the number of awards expected to be forfeited and adjusting the estimate when it is likely to change, as is currently required. The Company adopted ASU 2016-09 on January 1, 2017, as required. The adoption did not have a material impact on the Company’s condensed consolidated financial statements and related disclosures.

Recent Accounting Pronouncements

In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers, which requires entities to recognize revenue in a way that depicts 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 those goods or services. The new guidance also requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts, including significant judgments and changes in judgments and assets recognized from costs incurred to obtain or fulfill a contract. The FASB has subsequently issued ASU 2016-10, Revenue from Contracts with Customers: (Topic 606) Identifying Performance Obligations and Licensing to address issues arising from implementation of the new revenue recognition standard. ASU 2014-09 and ASU 2016-10 are effective for interim and annual periods beginning January 1, 2018, and may be adopted earlier, but not before January 1, 2017. The revenue standards are required to be adopted by taking either a full retrospective or a modified retrospective approach. As of June 30, 2017, the Company has not elected early adoption and has not concluded on an adoption method. The Company is in the process of analyzing the Company’s collaboration agreement and the potential impact the standard may have on previously reported revenues and future revenues. The Company is still evaluating the impact on the condensed consolidated financial statements and related disclosures.

In January 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities. ASU 2016-01 requires equity investments to be measured at fair value with changes in fair value recognized in net income; simplifies the impairment assessment of equity investments without readily determinable fair values by requiring a qualitative assessment to identify impairment; eliminates the requirement for public business entities to disclose the method(s) and significant assumptions used to estimate the fair value that is required to be disclosed for financial instruments measured at amortized cost on the balance sheet; requires public business entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes; requires an entity to present separately in other comprehensive income the portion of the total change in the fair value of a liability resulting from a change in the instrument-specific credit risk when the entity has elected to measure the liability at fair value in accordance with the fair value option for financial instruments; requires separate presentation of financial assets and financial liabilities by measurement category and form of financial assets on the balance sheet or the accompanying notes to the financial statements and clarifies that an entity should evaluate the need for a valuation allowance on a deferred tax asset related to available-for-sale securities in combination with the entity’s other deferred tax assets. ASU 2016-01 is effective for financial statements issued for fiscal years beginning after December 15, 2017 and interim periods within those fiscal years. The Company is currently evaluating the impact that ASU 2016-01 will have on its condensed consolidated financial statements and related disclosures.

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842), which supersedes FASB Topic 840, Leases (Topic 840) and provides principles for the recognition, measurement, presentation and disclosure of leases for both lessees and lessors. The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification will determine whether lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease, respectively. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than twelve months regardless of classification. Leases with a term of twelve months or less will be accounted for similarly to existing guidance for operating leases. The standard will be effective for annual and interim periods beginning after December 15, 2018, with early adoption permitted upon issuance. The Company is currently evaluating the impact that ASU 2016-02 will have on its condensed consolidated financial statements and related disclosures.

In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments. ASU 2016-13 requires that expected credit losses relating to financial assets measured on an amortized cost basis and available-for-sale debt securities be recorded through an allowance for credit losses. ASU 2016-13 limits the amount of credit losses to be recognized for available-for-sale debt securities to the amount by which carrying value exceeds fair value and also requires the reversal of previously recognized credit losses if fair value increases. The new standard will be effective on January 1, 2020. Early adoption will be available on January 1, 2019. The Company is currently evaluating the effect that the updated standard will have on its condensed consolidated financial statements and related disclosures.

In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows - Classification of Certain Cash Receipts and Cash Payments, which addresses eight specific cash flow issues with the objective of reducing the existing diversity in practice in how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The standard is effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. Early adoption is permitted, including adoption in an interim period. The Company is currently in the process of evaluating the impact of this new pronouncement on its condensed consolidated statements of cash flows and related disclosures.

In January 2017, the FASB issued ASU 2017-01, Business Combinations (Topic 805) Clarifying the Definition of a Business, which clarifies the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The definition of a business affects many areas of accounting including acquisitions, disposals, goodwill, and consolidation. The standard is effective for annual periods beginning after December 15, 2017, including interim periods within those periods. The Company is currently evaluating the impact of adopting this guidance.

In January 2017, the FASB issued ASU 2017-04, Intangibles - Goodwill and Other (Topic 350): Simplifying the Accounting for Goodwill Impairment. ASU 2017-04 removes Step 2 of the goodwill impairment test, which requires a hypothetical purchase price allocation. A goodwill impairment will now be the amount by which a reporting unit’s carrying value exceeds its fair value, not to exceed the carrying amount of goodwill. This standard, which will be effective for the Company beginning in the first quarter of fiscal year 2021, is required to be applied prospectively. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company is currently evaluating the impact this standard will have on its condensed consolidated financial statements.

In May 2017, the FASB issued ASU 2017-09, Compensation-Stock Compensation (Topic 718): Scope of Modification Accounting,. ASU 2017-09 provides clarity and reduces both (1) diversity in practice and (2) cost and complexity when applying the guidance in Topic 718, to a change to the terms or conditions of a share-based payment award. The amendments in ASU 2017-09 should be applied prospectively to an award modified on or after the adoption date. This ASU is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017. The Company is currently evaluating the impact this standard will have on its condensed consolidated financial statements.

Marketable Securities

6 Months Ended

Jun. 30, 2017

Investments, Debt and Equity Securities [Abstract]

Marketable Securities

Note 3 - Marketable Securities

Marketable securities consist of the following as of June 30, 2017 and December 31, 2016:

	June 30, 2017
	Amortized Cost		Gross Unrealized Gain ⁽¹⁾		Gross Unrealized Loss ⁽¹⁾		Fair Value
Short-term available-for-sale securities
Corporate bonds	$	36,255,433	$	10,173	$	(141,922)	$	36,123,684

Long-term available-for-sale securities
Corporate bonds	$	3,012,100	$	-	$	(3,260)	$	3,008,840
Total	$	39,267,533	$	10,173	$	(145,182)	$	39,132,524

(1) pre-tax

	December 31, 2016
	Amortized Cost		Gross Unrealized Gain ⁽¹⁾		Gross Unrealized Loss ⁽¹⁾		Fair Value
Short-term available-for-sale securities
Corporate bonds	$	22,032,191	$	3,190	$	(473,056)	$	21,562,325
Government and agency obligations		1,225,000		661		-		1,225,661
Municipal bonds		1,596,160		4,257		-		1,600,417
		24,853,351		8,108		(473,056)		24,388,403

Long-term available-for-sale securities
Corporate bonds		2,434,251		1,502		-		2,435,753
		2,434,251		1,502		-		2,435,753
Total	$	27,287,602	$	9,610	$	(473,056)	$	26,824,156

⁽¹⁾ Gross unrealized gain (loss) is pre-tax.

The contractual term to maturity of short-term marketable securities held by the Company as of June 30, 2017 is less than one year. The weighted average contractual term to maturity of long-term marketable securities held by the Company is approximately 1.1 years as of June 30, 2017.

The fair value of marketable securities was classified into fair value measurement categories as of June 30, 2017 and December 31, 2016 as follows:

	June 30,		December 31,
	2017		2016
Quoted prices in active markets for identical assets (Level 1)	$	-	$	-
Quoted prices for similar assets observable in the marketplace (Level 2)		39,132,524		26,824,156
Significant unobservable inputs (Level 3)		-		-
Total	$	39,132,524	$	26,824,156

The fair values of marketable securities are determined using quoted market prices from daily exchange traded markets based on the closing prices as of June 30, 2017 and December 31, 2016.

There were no transfers of marketable securities between Levels 1, 2 or 3 for the six months ended June 30, 2017 and 2016.

The following table shows the Company’s investments’ gross unrealized losses and fair value, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, at June 30, 2017.

	Less than 12 Months				12 Months or More				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
Corporate bonds	$	4,152,931	$	(4,413)	$	29,289,584	$	(140,769)	$	33,442,515	$	(145,182)
Total	$	4,152,931	$	(4,413)	$	29,289,584	$	(140,769)	$	33,442,515	$	(145,182)

The Company has determined that the unrealized losses are deemed to be temporary impairments as of June 30, 2017. The Company believes that the unrealized losses generally are caused by increases in the risk premiums required by market participants rather than an adverse change in cash flows or a fundamental weakness in the credit quality of the issuer or underlying assets. Because the Company has the ability and intent to hold these investments until a recovery of fair value, which may be maturity, it does not consider the investment in corporate bonds to be other-than-temporarily impaired at June 30, 2017.

Property, Plant and Equipment, Net

6 Months Ended

Jun. 30, 2017

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment, Net

Note 4 - Property, Plant and Equipment, Net

Property, plant and equipment, consists of the following:

		June 30,		December 31,
	Useful life (Years)	2017		2016
Computer hardware and software	3	$	86,228	$	86,228
Lab equipment	3 to 5		253,735		253,735
Office equipment	3 to 5		1,109		1,109
Leasehold improvement	1		68,213		68,213
Total property, plant and equipment			409,285		409,285
Less: Accumulated depreciation and amortization			(277,428)		(194,598)
Property, plant and equipment, net		$	131,857	$	214,687

Depreciation expense for the three months ended June 30, 2017 and 2016 was approximately $51,000 and $18,000, respectively, and was recorded in both research and development expense and general and administrative expense in the condensed consolidated statements of operations.

Depreciation expense for the six months ended June 30, 2017 and 2016 was approximately $83,000 and $37,000, respectively, and was recorded in both research and development expense and general and administrative expense in the condensed consolidated statements of operations.

Accrued Expenses

6 Months Ended

Jun. 30, 2017

Payables and Accruals [Abstract]

Accrued Expenses

Note 5 - Accrued Expenses

Accrued expenses consist of the following:

	June 30,		December 31,
	2017		2016
Accrued expenses:
Salaries, bonuses and employee benefits	$	2,585,127	$	2,884,000
Accrued severance expenses		310,298		241,737
Research and development expenses		2,771,227		916,674
General and administrative expenses		638,895		710,412
Total accrued expenses	$	6,305,547	$	4,752,823

Stockholders' Equity

6 Months Ended

Jun. 30, 2017

Equity [Abstract]

Stockholders' Equity

Note 6 - Stockholders’ Equity

Common Stock

For the six months ended June 30, 2017, the Company issued an aggregate of 113,935 shares of common stock and received gross proceeds of approximately $0.7 million from the exercise of options.

Options

In July 2010, the stockholders approved the 2010 Equity Incentive Plan (the 2010 Plan). As of June 30, 2017, there were outstanding options to purchase an aggregate of 610,334 shares of common stock under the 2010 Plan. Effective on June 2, 2016, the 2010 Plan was frozen and no further grants will be made under the 2010 Plan. Shares that are forfeited under the 2010 Plan on or after June 2, 2016 will become available for issuance under the Amended and Restated 2014 Plan (as defined below).

In July 2014, the stockholders approved the 2014 Stock Incentive Plan (the 2014 Plan). On June 2, 2016, at the 2016 Annual Meeting of Stockholders, the stockholders of the Company approved the amendment and restatement of the Company’s 2014 Plan (the Amended and Restated 2014 Plan). Pursuant to the terms of the Amended and Restated 2014 Plan, the maximum number of shares reserved for issuance thereunder is 4,160,000 (representing an increase of 1,600,000). As of June 30, 2017, there were outstanding options to purchase an aggregate of 3,541,141 shares of common stock and 485,155 shares available for grant under the Amended and Restated 2014 Plan. Additionally, 73,126 shares of common stock forfeited under the 2010 Plan are available for issuance under the Amended and Restated 2014 Plan.

On April 3, 2017, the Board of Directors of the Company adopted the Assembly Biosciences, Inc. 2017 Inducement Award Plan (the Inducement Plan) pursuant to which the Company reserved 800,000 shares of common stock for issuance under the Inducement Plan. The only persons eligible to receive grants of awards under the Inducement Plan are individuals who satisfy the standards for inducement grants under Nasdaq Marketplace Rule 5635(c)(4) and the related guidance under Nasdaq IM-5635-1. An “Award” is any right to receive Assembly common stock pursuant to the Inducement Plan, consisting of nonstatutory stock options, stock appreciation rights, dividend equivalent rights, restricted stock awards, restricted stock unit awards, or any other stock award. As of June 30, 2017, there were outstanding options to purchase an aggregate of 89,750 shares of common stock and 710,250 shares available for grant under the Inducement Plan.

Pursuant to the terms of the merger of Assembly Pharmaceuticals, Inc. with a wholly-owned subsidiary of the Company in 2014, the options to purchase shares of Assembly Pharmaceuticals’ common stock issued and outstanding immediately prior to the merger were assumed by the Company and became exercisable for an aggregate of 621,651 shares of the Company’s common stock. As of June 30, 2017, assumed options to purchase an aggregate of 596,239 shares of common stock were outstanding.

A summary of the Company’s option activity and related information for the six-month period ended June 30, 2017 is as follows:

	Number of Shares		Weighted Average Exercise Price		Total Intrinsic Value
Outstanding as of December 31, 2016		4,457,251	$	7.14	$	23,258,604
Granted		583,250		22.93		784,000
Exercised		(117,827)		7.13		-
Forfeited		(85,210)		9.71		-
Outstanding as of June 30, 2017		4,837,464	$	9.00	$	58,428,762
Options vested and exercisable		3,200,688	$	6.70	$	44,640,661

The fair value of the options granted for the six months ended June 30, 2017 and 2016, were based on the following assumptions:

	Six Months Ended June 30,
	2017		2016
Exercise price		$12.81 - $25.96		$5.84 - $7.03
Expected stock price volatility		84.4% - 87.0%		88.2% - 91.8%
Risk-free rate of interest		2.02% - 2.23%		1.36% - 1.94%
Expected term (years)		5.5 - 7.0		5.4 - 7.0

Estimated future stock-based compensation expense relating to unvested stock options is as follows:

	Future Stock Option Compensation Expenses
Six Months Ended December 31, 2017	$	4,648,866
Year Ended December 31, 2018		4,775,098
Year Ended December 31, 2019		1,355,710
Year Ended December 31, 2020		441,243
Year Ended December 31, 2021		15,854
Total	$	11,236,771

Unamortized stock-based compensation expense amounted to approximately $11.2 million at June 30, 2017. The weighted average remaining amortization period is approximately 1.5 years at June 30, 2017. Effective on January 1, 2017, the Company elected to account for forfeitures as they occur as permitted by ASU 2016-09. Ultimately, the actual expenses recognized over the vesting period will be for those shares that vested. Prior to making this election, the Company estimated their forfeiture rate at 0%, or they did not have a significant history of forfeitures.

Stock-based compensation expense for the three and six months ended June 30, 2017 and 2016 is as follows:

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Research and development	$	1,226,269	$	850,851	$	2,178,195	$	1,569,007
General and administrative		784,992		667,287		1,057,713		1,408,986
Total stock-based compensation expense	$	2,011,261	$	1,518,138	$	3,235,908	$	2,977,993

Warrants

There was no warrant activity for the six months ended June 30, 2017. The weighted average remaining contractual life of outstanding warrants to purchase 16,909 shares of common stock at June 30, 2017 is approximately 2.9 years.

Collaboration Agreement

6 Months Ended

Jun. 30, 2017

Organization, Business and Basis Of Presentation [Abstract]

Collaboration Agreement

Note 7 - Collaboration Agreement

On January 6, 2017, the Company entered into the Collaboration Agreement with Allergan to develop and commercialize select microbiome gastrointestinal programs. Pursuant to the Collaboration Agreement, the Company granted Allergan an exclusive worldwide license to certain of its intellectual property, including its intellectual property arising under the Collaboration Agreement, to develop and commercialize licensed compounds for ulcerative colitis (UC), Crohn’s disease, and irritable bowel syndrome (IBS).

Under the Collaboration Agreement, Allergan and the Company will collaborate on research and development activities with respect to the licensed compounds in accordance with a mutually agreed upon research and development plan.

Pursuant to the terms of the Collaboration Agreement, in connection with the closing of the transaction on February 10, 2017, Allergan paid the Company an upfront payment of $50 million. Additionally, the Company is eligible to receive up to approximately $630 million in payments related to seven development milestones and up to approximately $2.15 billion in payments related to 12 commercial development and sales milestones in connection with the successful development and commercialization of licensed compounds for up to six different indications. At the time of execution of the Collaboration Agreement, there was significant uncertainty as to whether the stated milestones would be achieved. In conjunction with this uncertainty, the Company has determined that the milestones are substantive in nature as they are commensurate with the enhancement of value of the delivered license as they relate to clinical success and advancement within the FDA drug development platform. In addition, the Company is eligible to receive tiered royalties at rates ranging from the mid-single digits to the mid-teens based on net sales. Allergan and the Company have agreed to share development costs up to an aggregate of $75 million through proof-of-concept (POC) studies on a ⅔, ⅓ basis, respectively, and Allergan has agreed to assume all post-POC development costs. In the event any pre-POC development costs exceed $75 million in the aggregate, the Company may elect either (a) to fund ⅓ of such costs in excess of $75 million or (b) to allow Allergan to deduct from future development milestone payments ⅓ of the development costs funded by Allergan in excess of $75 million plus a premium of 25%. The Company has an option to co-promote the licensed programs in the United States and China, subject to certain conditions set forth in the Collaboration Agreement.

Allergan may terminate the Collaboration Agreement for convenience at any time upon either 90 days’ (prior to the initiation of the first POC trial of a licensed product) or 120 days’ (after the initiation of the first POC trial of a licensed product), as applicable, advance written notice to the Company. The Collaboration Agreement also contains customary provisions for termination by either party, including in the event of breach of the Collaboration Agreement, subject to cure.

The Collaboration Agreement meets the definition of a collaborative arrangement and a multiple-element arrangement. The Company concluded that there were two significant deliverables under the Collaboration Agreement for each of four indicators - the licenses and the research and development services - but that the license does not have stand-alone value as Allergan cannot obtain value from the license without the research and development services, which the Company is uniquely able to perform. The deferred revenue will be amortized over a 10-year service period. As such, the Company recognized the upfront payment received of $50.0 million as approximately $5.0 million in short-term deferred revenue and $45.0 million in long-term deferred revenue as of the closing date. Given the early stage of development, the Company has determined the relative selling price for each of the four indicators to be $12.5 million and expects the elements to deliver over similar times. For the three and six months ended June 30, 2017, the Company recorded approximately $1.2 million and $1.9 million, respectively, in revenue related to the amortization of deferred revenue. Expense reimbursements will be recognized as collaboration revenue when the related expenses are incurred. The reimbursable expenses incurred in connection with the Collaboration Agreement during the six months ended June 30, 2017 were $1.1 million and recorded in collaboration revenue on the condensed consolidated statement of operations.

Commitments and Contingencies

6 Months Ended

Jun. 30, 2017

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Note 8 - Commitments and Contingencies

Real Property Leases

The Company leases office space for corporate functions in Carmel, Indiana under a lease agreement that expires in August 2023. The leased location in Carmel, Indiana supports both the HBV-cure and Microbiome programs. The Company leases office and laboratory space in San Francisco, California under a sublease that expires in December 2017, unless the Company requests a six month extension by October 2, 2017. The Company also conducted research activities for the HBV-cure program at laboratory space leased from Indiana University at Bloomington, Indiana until May 2017. The Company transferred the activities that it performed at Indiana University to its Carmel, Indiana and San Francisco, California locations. The Company also conducts research activities for the Microbiome program at office and laboratory space in Groton, Connecticut under a lease that expires in March 2018. The Company ceased leasing office and laboratory space from the University of Florida Research Foundation in Alachua, Florida in May 2017.

The total leasing expenses for the three months ended June 30, 2017 and 2016 were approximately $0.3 million and $0.4 million, respectively. The total leasing expenses for the six months ended June 30, 2017 and 2016 were approximately $0.6 million and $0.8 million, respectively.

Equipment Lease

Pursuant to a Master Lease agreement dated November 25, 2014, the Company leases certain equipment. The equipment lease expense for the three months ended June 30, 2017 and 2016 amounted to approximately $180,000 and $165,000, respectively. The equipment lease expense for the six months ended June 30, 2017 and 2016 amounted to approximately $359,000 and $256,000, respectively. These equipment leases began to expire in 2017, with the final lease expiring in 2020. The sum of all future payments through termination is approximately $1.3 million.

Litigation

The Company is not a party to any material legal proceedings and is not aware of any claims or actions pending or threatened against it. From time to time, the Company may be subject to various legal proceedings and claims that arise in the ordinary course of its business activities.

Summary of Significant Accounting Policies and Recent Accounting Pronouncements (Policies)

6 Months Ended

Jun. 30, 2017

Accounting Policies [Abstract]

Basis of presentation

Basis of Presentation

Use of Estimates

Use of Estimates

Significant Accounting Policies

Significant Accounting Policies

Revenue Recognition

Revenue Recognition

Loss per Share of Common Stock

Loss per Share of Common Stock

	Six Months Ended June 30,
	2017		2016
Warrants to purchase common stock		16,909		16,909
Options to purchase common stock		4,837,464		4,097,952
Total		4,854,373		4,114,861

Recent Accounting Pronouncements

Adoption of Recent Accounting Pronouncements

Recent Accounting Pronouncements

Summary of Significant Accounting Policies and Recent Accounting Pronouncements (Tables)

6 Months Ended

Jun. 30, 2017

Accounting Policies [Abstract]

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share

Securities that could potentially result in diluted loss per share in the future that were not included in the computation of diluted loss per share at June 30, 2017 and 2016 are as follows:

	Six Months Ended June 30,
	2017		2016
Warrants to purchase common stock		16,909		16,909
Options to purchase common stock		4,837,464		4,097,952
Total		4,854,373		4,114,861

Marketable Securities (Tables)

6 Months Ended

Jun. 30, 2017

Investments, Debt and Equity Securities [Abstract]

Schedule of Available-for-sale Securities Reconciliation

Marketable securities consist of the following as of June 30, 2017 and December 31, 2016:

	June 30, 2017
	Amortized Cost		Gross Unrealized Gain ⁽¹⁾		Gross Unrealized Loss ⁽¹⁾		Fair Value
Short-term available-for-sale securities
Corporate bonds	$	36,255,433	$	10,173	$	(141,922)	$	36,123,684

Long-term available-for-sale securities
Corporate bonds	$	3,012,100	$	-	$	(3,260)	$	3,008,840
Total	$	39,267,533	$	10,173	$	(145,182)	$	39,132,524

(1) pre-tax

	December 31, 2016
	Amortized Cost		Gross Unrealized Gain ⁽¹⁾		Gross Unrealized Loss ⁽¹⁾		Fair Value
Short-term available-for-sale securities
Corporate bonds	$	22,032,191	$	3,190	$	(473,056)	$	21,562,325
Government and agency obligations		1,225,000		661		-		1,225,661
Municipal bonds		1,596,160		4,257		-		1,600,417
		24,853,351		8,108		(473,056)		24,388,403

Long-term available-for-sale securities
Corporate bonds		2,434,251		1,502		-		2,435,753
		2,434,251		1,502		-		2,435,753
Total	$	27,287,602	$	9,610	$	(473,056)	$	26,824,156

⁽¹⁾ Gross unrealized gain (loss) is pre-tax.

Schedule Of Available For Sale Securities Fair Value Measurement Categories

The fair value of marketable securities was classified into fair value measurement categories as of June 30, 2017 and December 31, 2016 as follows:

	June 30,		December 31,
	2017		2016
Quoted prices in active markets for identical assets (Level 1)	$	-	$	-
Quoted prices for similar assets observable in the marketplace (Level 2)		39,132,524		26,824,156
Significant unobservable inputs (Level 3)		-		-
Total	$	39,132,524	$	26,824,156

Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value

	Less than 12 Months				12 Months or More				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
Corporate bonds	$	4,152,931	$	(4,413)	$	29,289,584	$	(140,769)	$	33,442,515	$	(145,182)
Total	$	4,152,931	$	(4,413)	$	29,289,584	$	(140,769)	$	33,442,515	$	(145,182)

Property, Plant and Equipment, Net (Tables)

6 Months Ended

Jun. 30, 2017

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

Property, plant and equipment, consists of the following:

		June 30,		December 31,
	Useful life (Years)	2017		2016
Computer hardware and software	3	$	86,228	$	86,228
Lab equipment	3 to 5		253,735		253,735
Office equipment	3 to 5		1,109		1,109
Leasehold improvement	1		68,213		68,213
Total property, plant and equipment			409,285		409,285
Less: Accumulated depreciation and amortization			(277,428)		(194,598)
Property, plant and equipment, net		$	131,857	$	214,687

Accrued Expenses (Tables)

6 Months Ended

Jun. 30, 2017

Payables and Accruals [Abstract]

Schedule Accrued Expenses

Accrued expenses consist of the following:

	June 30,		December 31,
	2017		2016
Accrued expenses:
Salaries, bonuses and employee benefits	$	2,585,127	$	2,884,000
Accrued severance expenses		310,298		241,737
Research and development expenses		2,771,227		916,674
General and administrative expenses		638,895		710,412
Total accrued expenses	$	6,305,547	$	4,752,823

Stockholders' Equity (Tables)

6 Months Ended

Jun. 30, 2017

Stockholders' Transactions [Abstract]

Disclosure of Share-based Compensation Arrangements by Share-based Payment Award

A summary of the Company’s option activity and related information for the six-month period ended June 30, 2017 is as follows:

	Number of Shares		Weighted Average Exercise Price		Total Intrinsic Value
Outstanding as of December 31, 2016		4,457,251	$	7.14	$	23,258,604
Granted		583,250		22.93		784,000
Exercised		(117,827)		7.13		-
Forfeited		(85,210)		9.71		-
Outstanding as of June 30, 2017		4,837,464	$	9.00	$	58,428,762
Options vested and exercisable		3,200,688	$	6.70	$	44,640,661

Assumptions for Weighted Average Fair Value of Options Granted

The fair value of the options granted for the six months ended June 30, 2017 and 2016, were based on the following assumptions:

	Six Months Ended June 30,
	2017		2016
Exercise price		$12.81 - $25.96		$5.84 - $7.03
Expected stock price volatility		84.4% - 87.0%		88.2% - 91.8%
Risk-free rate of interest		2.02% - 2.23%		1.36% - 1.94%
Expected term (years)		5.5 - 7.0		5.4 - 7.0

Estimated Future Stock Based Expenses Relating to Unvested Stock Options

Estimated future stock-based compensation expense relating to unvested stock options is as follows:

	Future Stock Option Compensation Expenses
Six Months Ended December 31, 2017	$	4,648,866
Year Ended December 31, 2018		4,775,098
Year Ended December 31, 2019		1,355,710
Year Ended December 31, 2020		441,243
Year Ended December 31, 2021		15,854
Total	$	11,236,771

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs

Stock-based compensation expense for the three and six months ended June 30, 2017 and 2016 is as follows:

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Research and development	$	1,226,269	$	850,851	$	2,178,195	$	1,569,007
General and administrative		784,992		667,287		1,057,713		1,408,986
Total stock-based compensation expense	$	2,011,261	$	1,518,138	$	3,235,908	$	2,977,993

Nature of Business - Additional Information (Details) - USD ($) $ in Millions		6 Months Ended
	Feb. 10, 2017	Jun. 30, 2017
Overview [Line Items]
Licenses Revenue	$ 50
Revenue Recognition, Milestone Method, Description		the Company is eligible to receive up to approximately $630 million in payments related to seven development milestones and up to approximately $2.15 billion in payments related to 12 commercial development and sales milestones in connection with the successful development and commercialization of licensed compounds for up to six different indications
Allergan Pharmaceuticals International Limited [Member]
Overview [Line Items]
Agreed To Share Maximum Amount Development Cost	$ 75
Revenue Recognition, Milestone Method, Description	the Company is eligible to receive up to approximately $630 million in payments related to seven development milestones and up to approximately $2.15 billion in payments related to 12 commercial development and sales milestones in connection with the successful development and commercialization of licensed compounds for up to six different indications

Summary of Significant Accounting Policies and Recent Accounting Pronouncements (Details) - shares	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	4,854,373	4,114,861
Warrants To Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	16,909	16,909
Options To Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	4,837,464	4,097,952

Marketable Securities (Details) - USD ($)

Jun. 30, 2017

Dec. 31, 2016

Schedule of Available-for-sale Securities [Line Items]

Amortized Cost

$ 39,267,533

$ 27,287,602

Gross Unrealized Gain

10,173

^[1]

9,610

^[2]

Gross Unrealized Loss

(145,182)

^[1]

(473,056)

^[2]

Fair Value

39,132,524

26,824,156

Short-term Investments [Member]

Schedule of Available-for-sale Securities [Line Items]

Amortized Cost

24,853,351

Gross Unrealized Gain

^[2]

8,108

Gross Unrealized Loss

^[2]

(473,056)

Fair Value

24,388,403

Short-term Investments [Member] | Corporate Bond Securities [Member]

Schedule of Available-for-sale Securities [Line Items]

Amortized Cost

36,255,433

22,032,191

Gross Unrealized Gain

10,173

^[1]

3,190

^[2]

Gross Unrealized Loss

(141,922)

^[1]

(473,056)

^[2]

Fair Value

36,123,684

21,562,325

Short-term Investments [Member] | US Government Agencies Debt Securities [Member]

Schedule of Available-for-sale Securities [Line Items]

Amortized Cost

1,225,000

Gross Unrealized Gain

^[2]

661

Gross Unrealized Loss

^[2]

Fair Value

1,225,661

Short-term Investments [Member] | Municipal Bonds [Member]

Schedule of Available-for-sale Securities [Line Items]

Amortized Cost

1,596,160

Gross Unrealized Gain

^[2]

4,257

Gross Unrealized Loss

^[2]

Fair Value

1,600,417

Long-term Investments [Member]

Schedule of Available-for-sale Securities [Line Items]

Amortized Cost

2,434,251

Gross Unrealized Gain

^[2]

1,502

Gross Unrealized Loss

^[2]

Fair Value

2,435,753

Long-term Investments [Member] | Corporate Bond Securities [Member]

Schedule of Available-for-sale Securities [Line Items]

Amortized Cost

3,012,100

2,434,251

Gross Unrealized Gain

^[1]

1,502

^[2]

Gross Unrealized Loss

(3,260)

^[1]

^[2]

Fair Value

$ 3,008,840

$ 2,435,753

[1]	pre-tax
[2]	Gross unrealized gain (loss) is pre-tax.

Marketable Securities (Details 1) - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	$ 39,132,524	$ 26,824,156
Fair Value, Inputs, Level 1 [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	0	0
Fair Value, Inputs, Level 2 [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	39,132,524	26,824,156
Fair Value, Inputs, Level 3 [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities	$ 0	$ 0

Marketable Securities (Details 2)	Jun. 30, 2017 USD ($)
Schedule of Available-for-sale Securities [Line Items]
Fair Value, Less than 12 Months	$ 4,152,931
Unrealized Losses, Less than 12 Months	(4,413)
Fair Value, 12 Months or More	29,289,584
Unrealized Losses,12 Months or More	(140,769)
Fair Value, Total	33,442,515
Unrealized Losses, Total	(145,182)
Corporate Bond Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value, Less than 12 Months	4,152,931
Unrealized Losses, Less than 12 Months	(4,413)
Fair Value, 12 Months or More	29,289,584
Unrealized Losses,12 Months or More	(140,769)
Fair Value, Total	33,442,515
Unrealized Losses, Total	$ (145,182)

Marketable Securities - Additional Information (Details)	6 Months Ended
	Jun. 30, 2017
Short-term Investments [Member]
Available For Sale Securities Maturity Term	less than one year
Other Long-term Investments [Member]
Available For Sale Securities Maturity Term	1.1 years

Property, Plant and Equipment, Net (Details) - USD ($)	6 Months Ended
Property, Plant and Equipment, Net (Details) - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 409,285	$ 409,285
Less: Accumulated depreciation and amortization	(277,428)	(194,598)
Property, plant and equipment, net	131,857	214,687
Computer hardware and software [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 86,228	86,228
Property, Plant and Equipment, Useful Life	3 years
Lab equipment [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 253,735	253,735
Lab equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Lab equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Office equipment [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 1,109	1,109
Office equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Office equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 68,213	$ 68,213
Property, Plant and Equipment, Useful Life	1 year

Property, Plant and Equipment, Net - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Property, Plant and Equipment [Line Items]
Depreciation	$ 51,000	$ 18,000	$ 82,830	$ 37,093

Accrued Expenses (Details) - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Accrued expenses:
Salaries, bonuses and employee benefits	$ 2,585,127	$ 2,884,000
Accrued severance expenses	310,298	241,737
Research and development expenses	2,771,227	916,674
General and administrative expenses	638,895	710,412
Total accrued expenses	$ 6,305,547	$ 4,752,823

Stockholders' Equity (Details) - Stock Option [Member]	6 Months Ended
Stockholders' Equity (Details) - Stock Option [Member]	Jun. 30, 2017 USD ($) $ / shares shares
Number of Shares
Option, Outstanding at beginning of period \| shares	4,457,251
Option, Granted \| shares	583,250
Option, Exercised \| shares	(117,827)
Option, Forfeited \| shares	(85,210)
Option, Outstanding at end of period \| shares	4,837,464
Options vested and exercisable \| shares	3,200,688
Weighted Average Exercise Price
Option, Outstanding at beginning of period \| $ / shares	$ 7.14
Option, Granted \| $ / shares	22.93
Option, Exercised \| $ / shares	7.13
Option, Forfeited \| $ / shares	9.71
Option, Outstanding at end of period \| $ / shares	9
Options vested and exercisable \| $ / shares	$ 6.7
Total Intrinsic Value
Option, Outstanding at beginning of period \| $	$ 23,258,604
Option, Granted \| $	784,000
Option, Exercised \| $	0
Option, Forfeited \| $	0
Option, Outstanding at end of period \| $	58,428,762
Options vested and exercisable \| $	$ 44,640,661

Stockholders' Equity (Details 1) - $ / shares	6 Months Ended
Stockholders' Equity (Details 1) - $ / shares	Jun. 30, 2017	Jun. 30, 2016
Maximum [Member]
Share based Compensation Arrangement by Share based Payment Award, Fair Value Assumptions, Method Used [Line Items]
Exercise price	$ 25.96	$ 7.03
Expected stock price volatility	87.00%	91.80%
Risk-free rate of interest	2.23%	1.94%
Term (years)	7 years	7 years
Minimum [Member]
Share based Compensation Arrangement by Share based Payment Award, Fair Value Assumptions, Method Used [Line Items]
Exercise price	$ 12.81	$ 5.84
Expected stock price volatility	84.40%	88.20%
Risk-free rate of interest	2.02%	1.36%
Term (years)	5 years 6 months	5 years 4 months 24 days

Stockholders' Equity (Details 2)	Jun. 30, 2017 USD ($)
Stockholders Equity Note [Line Items]
Six Months Ended December 31, 2017	$ 4,648,866
Year ended December 31, 2018	4,775,098
Year ended December 31, 2019	1,355,710
Year ended December 31, 2020	441,243
Year Ended December 31, 2021	15,854
Total	$ 11,236,771

Stockholders' Equity (Details 3) - USD ($)	3 Months Ended		6 Months Ended
Stockholders' Equity (Details 3) - USD ($)	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated Share-based Compensation Expense	$ 2,011,261	$ 1,518,138	$ 3,235,908	$ 2,977,993
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated Share-based Compensation Expense	1,226,269	850,851	2,178,195	1,569,007
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated Share-based Compensation Expense	$ 784,992	$ 667,287	$ 1,057,713	$ 1,408,986

Stockholders' Equity - Additional Information (Details) - USD ($) $ in Millions			6 Months Ended
	Feb. 10, 2017	Jun. 02, 2016	Jun. 30, 2017	Apr. 03, 2017	Jul. 31, 2014
Stockholders Equity Note [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance				800,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition			1 year 6 months
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized			$ 11.2
Proceeds from Stock Options Exercised			$ 0.7
Class of Warrant or Right, Outstanding			16,909
Share-based Compensation Arrangement by Share-based Payment Award, Forfeiture Rate			0.00%
Revenue Recognition, Milestone Method, Description			the Company is eligible to receive up to approximately $630 million in payments related to seven development milestones and up to approximately $2.15 billion in payments related to 12 commercial development and sales milestones in connection with the successful development and commercialization of licensed compounds for up to six different indications
Warrant [Member]
Stockholders Equity Note [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term			2 years 10 months 24 days
Amended And Restated 2014 Plan [Member]
Stockholders Equity Note [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized			73,126
Common Stock [Member]
Stockholders Equity Note [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number					621,651
Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number			596,239
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period			113,935
2010 Stock Incentive Plan [Member]
Stockholders Equity Note [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number			610,334
2014 Stock Incentive Plan [Member]
Stockholders Equity Note [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number			3,541,141
Common Stock, Capital Shares Reserved for Future Issuance		4,160,000
Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Grants In Period, Gross			485,155
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized		1,600,000
2017 Stock Incentive Plan [Member]
Stockholders Equity Note [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number			89,750
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant			710,250
Allergan Pharmaceuticals International Limited [Member]
Stockholders Equity Note [Line Items]
Revenue Recognition, Milestone Method, Description	the Company is eligible to receive up to approximately $630 million in payments related to seven development milestones and up to approximately $2.15 billion in payments related to 12 commercial development and sales milestones in connection with the successful development and commercialization of licensed compounds for up to six different indications

Collaboration Agreement - Additional Information (Details) - USD ($)		3 Months Ended		6 Months Ended
	Feb. 10, 2017	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration revenue		$ 2,359,311	$ 0	$ 3,043,680	$ 0
Deferred Revenue,Amortization Period Over Service Tenure				10 years
Licenses Revenue	$ 50,000,000
Deferred Revenue, Current		4,995,894		$ 4,995,894		$ 0
Deferred Revenue, Noncurrent		$ 43,074,186		$ 43,074,186		$ 0
Revenue Recognition, Milestone Method, Description				the Company is eligible to receive up to approximately $630 million in payments related to seven development milestones and up to approximately $2.15 billion in payments related to 12 commercial development and sales milestones in connection with the successful development and commercialization of licensed compounds for up to six different indications
Reimbursement Revenue					$ 1,100,000
Collaborative Arrangement [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue Recognition, Multiple-deliverable Arrangements, Determination of Selling Price, Amount				$ 12,500,000
Allergan Pharmaceuticals International Limited [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue Recognition, Milestone Method, Description	the Company is eligible to receive up to approximately $630 million in payments related to seven development milestones and up to approximately $2.15 billion in payments related to 12 commercial development and sales milestones in connection with the successful development and commercialization of licensed compounds for up to six different indications
Description Of Agree To Share Development Cost	In the event any pre-POC development costs exceed $75 million in the aggregate, the Company may elect either (a) to fund ⅓ of such costs in excess of $75 million or (b) to allow Allergan to deduct from future development milestone payments ⅓ of the development costs funded by Allergan in excess of $75 million plus a premium of 25%.
Proceeds From Upfront Payment	$ 50,000,000
Agreed To Share Maximum Amount Development Cost	$ 75,000,000

Commitments and Contingencies - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Commitments and Contingencies Disclosure [Line Items]
Operating Leases, Rent Expense	$ 300,000	$ 400,000	$ 600,000	$ 800,000
Equipment Lease [Member]
Commitments and Contingencies Disclosure [Line Items]
Operating Leases, Rent Expense	180,000	$ 165,000	359,000	$ 256,000
Operating Leases, Future Minimum Payments Due	$ 1,300,000		$ 1,300,000
Operating Lease Expiration Year			2020