MacroGenics (MGNX) 10-Q 3 Aug 16 2016 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2016	Jul. 29, 2016
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q2
Entity Registrant Name	MACROGENICS INC
Entity Central Index Key	1,125,345
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	No
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		34,733,560

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 62,267	$ 196,172
Marketable securities	203,357	142,877
Accounts receivable	78,375	1,224
Prepaid expenses	3,782	1,806
Other current assets	663	305
Total current assets	348,444	342,384
Property and equipment, net	18,294	14,841
Other assets	2,112	2,044
Total assets	368,850	359,269
Current liabilities:
Accounts payable	1,150	2,967
Accrued expenses	12,342	11,708
Deferred revenue	4,578	5,866
Lease exit liability	1,459	2,020
Other liabilities	0	727
Total current liabilities	19,529	23,288
Deferred revenue, net of current portion	10,740	12,631
Lease exit liability, net of current portion	1,120	2,693
Deferred rent liability	6,758	7,320
Other Liabilities, Noncurrent	727	0
Total liabilities	38,874	45,932
Stockholders' equity:
Common stock, $0.01 par value - 125,000,000 shares authorized, 34,694,039 and 34,345,754 shares outstanding at June 30, 2016 and December 31, 2015, respectively	347	343
Additional paid-in capital	553,655	547,185
Accumulated deficit	(224,085)	(234,186)
Accumulated other comprehensive loss	59	(5)
Total stockholders' equity	329,976	313,337
Total liabilities and stockholders' equity	$ 368,850	$ 359,269

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Jun. 30, 2016	Dec. 31, 2015
Stockholders' equity:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	125,000,000	125,000,000
Common stock, shares outstanding (in shares)	34,694,039	34,345,754

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Revenues:
Revenue from collaborative research	$ 78,497	$ 5,598	$ 80,390	$ 76,763
Revenue from government agreements	2,176	1,118	3,129	1,232
Total revenues	80,673	6,716	83,519	77,995
Costs and expenses:
Research and development	33,340	22,660	60,686	44,124
General and administrative	7,239	5,346	13,372	10,029
Total costs and expenses	40,579	28,006	74,058	54,153
Income (loss) from operations	40,094	(21,290)	9,461	23,842
Other income (expense)	370	(86)	640	(89)
Net income (loss)	40,464	(21,376)	10,101	23,753
Other comprehensive income (loss):
Unrealized gain (loss) on investments	7	0	64	0
Comprehensive income (loss)	$ 40,471	$ (21,376)	$ 10,165	$ 23,753
Basic net income (loss) per common share (in dollars per share)	$ 1.17	$ (0.71)	$ 0.29	$ 0.80
Diluted net income (loss) per common share (in dollars per share)	$ 1.12	$ (0.71)	$ 0.28	$ 0.75
Basic weighted average number of common shares (in shares)	34,616,197	30,059,329	34,560,021	29,739,326
Diluted weighted average number of common shares (in shares)	36,017,411	30,059,329	35,966,987	31,797,332

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash flows from operating activities
Net income (loss)	$ 10,101	$ 23,753
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation expense	3,557	1,182
Share-based compensation	6,124	3,533
Changes in operating assets and liabilities:
Accounts receivable	(77,151)	(1,399)
Prepaid expenses	(1,976)	1,145
Other assets	(426)	0
Accounts payable	(355)	184
Accrued expenses	866	375
Lease exit liability	(2,134)	(2,383)
Deferred revenue	(3,179)	(7,812)
Deferred rent	(563)	(450)
Net cash provided by (used in) operating activities	(65,136)	18,128
Cash flows from investing activities
Purchases of marketable securities	(202,392)	0
Proceeds from sale and maturities of marketable securities	141,611	0
Purchases of property and equipment	(8,339)	(3,809)
Net cash used in investing activities	(69,120)	(3,809)
Cash flows from financing activities
Proceeds from issuance of common stock, net of offering costs	0	62,692
Proceeds from stock option exercises	351	425
Net cash provided by financing activities	351	63,117
Net change in cash and cash equivalents	(133,905)	77,436
Cash and cash equivalents at beginning of period	196,172	157,591
Cash and cash equivalents at end of period	$ 62,267	$ 235,027

Basis of Presentation and Recen

Basis of Presentation and Recently Issued Accounting Standards	6 Months Ended
	Jun. 30, 2016
Basis of Presentation and Recently Issued Accounting Standards
Basis of Presentation and Recently Issued Accounting Standards	1. Basis of Presentation and Recently Issued Accounting Standards Basis of Presentation The accompanying unaudited interim consolidated financial statements of MacroGenics, Inc. (the Company) have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information. The financial statements include all adjustments (consisting only of normal recurring adjustments) that the management of the Company believes are necessary for a fair presentation of the periods presented. These interim financial results are not necessarily indicative of results expected for the full fiscal year or for any subsequent interim period. The accompanying unaudited interim consolidated financial statements include the accounts of MacroGenics, Inc. and its wholly owned subsidiary, MacroGenics UK Limited. All intercompany accounts and transactions have been eliminated in consolidation. These consolidated financial statements and related notes should be read in conjunction with the financial statements and notes thereto included in the Company's 2015 Annual Report on Form 10-K filed with the Securities and Exchange Commission (SEC) on February 29, 2016. There have been no material changes to the significant accounting policies previously disclosed in the Company's 2015 Annual Report on Form 10-K other than the adoption of ASU No. 2015-17, Income Taxes, Balance Sheet Classification of Deferred Taxes, Recently Issued Accounting Standards In November 2015, the Financial Accounting Standards Board (FASB) issued ASU No. 2015-17, Income Taxes, Balance Sheet Classification of Deferred Taxes (ASU 2015-17). ASU 2015-17 requires entities to present deferred tax assets and deferred tax liabilities as noncurrent on a classified balance sheet. ASU 2015-17 is effective for annual and interim reporting periods after December 15, 2016 and companies are permitted to apply ASU 2015-17 either prospectively or retrospectively. Early adoption of ASU 2015-17 is permitted. The Company adopted ASU 2015-17 on a prospective basis in the first quarter of 2016. The prior reporting period was not retrospectively adjusted. The adoption of this guidance had no impact on the Company's results of operations or cash flows. In May 2014, FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (ASU 2014-09) as modified by ASU No. 2015-14, Revenue from Contracts with Customers: Deferral of the Effective Date (ASU 2014-14). ASU 2014-09 will eliminate transaction- and industry-specific revenue recognition guidance under current GAAP and replace it with a principle-based approach for determining revenue recognition. ASU 2014-09 will require that companies recognize revenue based on the value of transferred goods or services as they occur in the contract. The ASU also will require 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. ASU 2014-09 is effective for annual reporting periods beginning after December 15, 2017, and interim periods therein. Early adoption at the original effective date, for interim and annual reporting periods beginning after December 15, 2016, will be permitted. The new standard may be adopted either retrospectively or on a modified retrospective basis whereby the new standard would be applied to new contracts and existing contracts with remaining performance obligations as of the effective date, with a cumulative catch-up adjustment recorded to beginning retained earnings at the effective date for existing contracts with remaining performance obligations. Management is currently assessing which adoption method will be selected and what effect the adoption of ASU 2014-09 will have on the Company's consolidated financial statements and accompanying notes. In February 2016, FASB issued ASU No. 2016-02, Leases (ASU 2016-02) that provides principles for the recognition, measurement, presentation and disclosure of leases for both lessees and lessors. ASU 2016-02 requires a lessee to recognize assets and liabilities on the balance sheet for operating leases and changes many key definitions, including the definition of a lease. ASU 2016-02 includes a short-term lease exception for leases with a term of 12 months or less, in which a lessee can make an accounting policy election not to recognize lease assets and lease liabilities. Lessees will continue to differentiate between finance leases (previously referred to as capital leases) and operating leases, using classification criteria that are substantially similar to the previous guidance. ASU 2016-02 is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years, with earlier application permitted. The Company is currently evaluating the effect of the standard on its consolidated financial statements and related disclosures. In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting (ASU 2016-09). This amendment addresses several aspects of the 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. ASU 2016-09 is effective for fiscal years beginning after December 15, 2016, including interim periods within that year. Early adoption is permitted. The Company is evaluating the impact of the standard on its consolidated financial statements and related disclosures.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	6 Months Ended
	Jun. 30, 2016
Fair Value of Financial Instruments [Abstract]
Fair Value of Financial Instruments	2. Fair Value of Financial Instruments The Company's financial instruments consist of cash and cash equivalents, marketable securities, accounts receivable, accounts payable and accrued expenses. The carrying amount of accounts receivable, accounts payable and accrued expenses are generally considered to be representative of their respective fair values because of their short-term nature. The Company accounts for recurring and non-recurring fair value measurements in accordance with FASB Accounting Standards Codification (ASC) 820, Fair Value Measurements and Disclosures (ASC 820). ASC 820 defines fair value, establishes a fair value hierarchy for assets and liabilities measured at fair value, and requires expanded disclosures about fair value measurements. The ASC 820 hierarchy ranks the quality of reliability of inputs, or assumptions, used in the determination of fair value and requires assets and liabilities carried at fair value to be classified and disclosed in one of the following three categories: • Level 1 – Fair value is determined by using unadjusted quoted prices that are available in active markets for identical assets and liabilities. • Level 2 – Fair value is determined by using inputs other than Level 1 quoted prices that are directly or indirectly observable. Inputs can include quoted prices for similar assets and liabilities in active markets or quoted prices for identical assets and liabilities in inactive markets. Related inputs can also include those used in valuation or other pricing models, such as interest rates and yield curves that can be corroborated by observable market data. • Level 3 – Fair value is determined by inputs that are unobservable and not corroborated by market data. Use of these inputs involves significant and subjective judgments to be made by a reporting entity – e.g., determining an appropriate adjustment to a discount factor for illiquidity associated with a given security. The Company evaluates financial assets and liabilities subject to fair value measurements on a recurring basis to determine the appropriate level at which to classify them each reporting period. This determination requires the Company to make subjective judgments as to the significance of inputs used in determining fair value and where such inputs lie within the ASC 820 hierarchy. Financial assets measured at fair value on a recurring basis were as follows (in thousands): Fair Value Measurements at June 30, 2016 Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Total Level 1 Level 2 Level 3 Assets: Money market funds $ 47,713 $ 47,713 $ – $ – U.S. Treasury securities 5,263 – 5,263 – Government-sponsored enterprises 29,121 – 29,121 – Corporate debt securities 168,973 – 168,973 – Total assets measured at fair value (a) $ 251,070 $ 47,713 $ 203,357 $ – (a) Total assets measured at fair value at June 30, 2016, includes approximately $47.7 million reported in cash and cash equivalents on the balance sheet. Fair Value Measurements at December 31, 2015 Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Total Level 1 Level 2 Level 3 Assets: Money market funds $ 62,353 $ 62,353 $ – $ – U.S. Treasury securities 9,349 – 9,349 – Government-sponsored enterprises 41,202 – 41,202 – Corporate debt securities 137,928 – 137,928 – Total assets measured at fair value (a) $ 250,832 $ 62,353 $ 188,479 $ – (a) Total assets measured at fair value at December 31, 2015, includes approximately $108.0 million reported in cash and cash equivalents on the balance sheet. The fair value of Level 2 securities is determined from market pricing and other observable market inputs for similar securities obtained from various third-party data providers. These inputs either represent quoted prices for similar assets in active markets or have been derived from observable market data.

Investments

Investments	6 Months Ended
	Jun. 30, 2016
Investments [Abstract]
Investments	3. Investments Available-for-sale investments as of June 30, 2016 and December 31, 2015 were as follows (in thousands): June 30, 2016 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury securities $ 5,262 $ 1 $ - $ 5,263 Government-sponsored enterprises 29,109 12 - 29,121 Corporate debt securities 168,927 81 (35 ) 168,973 Total $ 203,298 $ 94 $ (35 ) $ 203,357 December 31, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury securities $ 9,354 $ 1 $ (6 ) $ 9,349 Government-sponsored enterprises 22,055 1 (9 ) 22,047 Corporate debt securities 111,473 42 (34 ) 111,481 Total $ 142,882 $ 44 $ (49 ) $ 142,877 All of the Company's available-for-sale investments held at June 30, 2016 and December 31, 2015 had maturity dates of less than one year, and all available-for-sale investments in an unrealized loss position as of June 30, 2016 and December 31, 2015 were in a loss position for less than twelve months. There were no unrealized losses at June 30, 2016 or December 31, 2015 that the Company determined to be other-than-temporary.

Lease Exit Liability

Lease Exit Liability	6 Months Ended
	Jun. 30, 2016
Lease Exit Liability [Abstract]
Lease Exit Liability	4. Lease Exit Liability On July 16, 2008, the Company acquired Raven Biotechnologies, Inc. (Raven), a private South San Francisco-based company focused on the development of monoclonal antibody therapeutics for treating cancer. Raven was considered a development-stage enterprise as defined in ASC 915, Development Stage Entities. The Company undertook restructuring activities related to the acquisition of Raven. In connection with these restructuring activities, as part of the cost of acquisition, the Company established a restructuring liability attributed to an existing operating lease. During the three months ended June 30, 2016, the Company entered into an agreement to sublease a portion of the space subject to this operating lease. The Company will receive approximately $1.3 million in sublease payments over its term, which ends at the same time as the original lease in February 2018. No sublease income was contemplated when the restructuring liability was recorded in 2008; therefore, the Company adjusted the liability to reflect the future sublease income during the three months ended June 30, 2016 and recorded an offset to research and development expenses of approximately $1.3 million in the same period. Changes in the lease exit liability are as follows (in thousands): Accrual balance at December 31, 2015 $ 4,713 Principal payments and other adjustments (2,134 ) Accrual balance at June 30, 2016 $ 2,579 The purchase agreement provides for a specified total of certain contingent milestones that are based on the achievement of certain product sales derived from the acquired Raven technology. Also, a onetime payment of $5.0 million will be made to the Raven stockholders upon the initiation of patient dosing in the first Phase 2 clinical trial of any product derived from the Raven "Cancer Stem Cell Program." No payment shall be made if the Phase 2 trial start date has not occurred on or before July 15, 2018. Other consideration may include a percentage of revenue (excluding consideration for research and development and equity) received by MacroGenics for license of a product derived from the Raven "Cancer Stem Cell Program" and a onetime payment ranging from $8.0 million to $12.0 million dependent upon a specified level of sales of products derived from the Raven "Cancer Stem Cell Program." The contingent consideration will be accounted for as additional purchase price and recorded as incremental in-process research and development expense when it is deemed probable that the contingencies will be attained. No additional amounts were recorded during the three and six months ended June 30, 2016 and 2015.

Collaboration and Other Agreeme

Collaboration and Other Agreements	6 Months Ended
	Jun. 30, 2016
Collaboration and License Agreements [Abstract]
Collaboration and License Agreements	5. Collaboration and Other Agreements Janssen Biotech, Inc. In December 2014, the Company entered into a collaboration and license agreement with Janssen Biotech, Inc. (Janssen) for the development and commercialization of MGD011 (also known as JNJ-64052781 or duvortuxizumab), a product candidate that incorporates the Company's proprietary DART® technology to simultaneously target CD19 and CD3 for the potential treatment of B-cell hematological malignancies. The Company contemporaneously entered into an agreement with Johnson & Johnson Innovation - JJDC, Inc. (JJDC) under which JJDC agreed to purchase 1,923,077 new shares of the Company's common stock for proceeds of $75.0 million. Upon closing the transaction in January 2015, the Company received a $50.0 million upfront payment from Janssen as well as the $75.0 million investment in the Company's common stock. Under the collaboration and license agreement, the Company granted an exclusive license to Janssen to develop and commercialize MGD011. Following the Company's submission of the Investigational New Drug (IND) application for MGD011, Janssen became fully responsible for the development and commercialization of MGD011. Assuming successful development and commercialization, the agreement entitled the Company to receive up to $205.0 million in development milestone payments, $220.0 million in regulatory milestone payments and $150.0 million in sales milestone payments. The Company determined that each potential future clinical and regulatory milestone is substantive. Although the sales milestones are not considered substantive, they will be recognized upon achievement of the milestone (assuming all other revenue recognition criteria have been met) because there are no undelivered elements that would preclude revenue recognition at that time. The Company may elect to fund a portion of late-stage clinical development in exchange for a profit share with Janssen in the U.S. and Canada. If commercialized, the Company would be eligible to receive low double-digit royalties on any global net sales and has the option to co-promote the molecule with Janssen in the United States. The Company evaluated the collaboration and license agreement with Janssen and determined that it is a revenue arrangement with multiple deliverables, or performance obligations. The Company's substantive performance obligations under the collaboration and license agreement include the delivery of an exclusive license and research and development services during the preclinical research period (through the filing of the IND application for MGD011). The Company evaluated the collaboration and license agreement with Janssen and determined that the license and preclinical research and development activities each represented separate deliverables and were accounted for as separate units of accounting. The Company concluded that the license had standalone value to Janssen and was separable from the research and development services because the license was sublicensable, there were no restrictions as to Janssen's use of the license and Janssen or other third parties have significant research capabilities in this field. Thus, the total arrangement consideration for these two deliverables was allocated using the relative best estimate of selling price method to each deliverable. The best estimate of selling price for the exclusive license was determined using a discounted cash flow model that includes Level 3 fair value measurements. The best estimate of selling price for the research and development services was determined using third party evidence of other similar research and development arrangements, which are Level 2 fair value measurements. The Company evaluated the stock purchase agreement and the collaboration and license agreement as one arrangement and determined that the stock purchase price of $39.00 per share exceeded the fair value of the common stock by $12.3 million. This excess was recognized in the same manner as the upfront payment allocated to the license and preclinical research and development activities. Of the total arrangement consideration of $125.0 million, the Company allocated $62.7 million to equity (representing the fair value of common stock purchased), $62.3 million to the license and preclinical research and development activities, and a de minimis amount to the ongoing research and development activities. The Company submitted the IND application and therefore met its performance obligation during the year ended December 31, 2015. In July 2015, Janssen dosed the first patient in an open-label Phase 1 study of MGD011 which triggered a $10.0 million milestone to the Company. During the six months ended June 30, 2015, the Company recognized revenues of approximately $62.3 million under the agreement. There was no revenue recognized under this agreement during the three or six months ended June 30, 2016. In May 2016, the Company entered into a separate collaboration and license agreement with Janssen, a related party through ownership of the Company's common stock, for the development and commercialization of MGD015, a product candidate that incorporates the Company's proprietary DART technology to simultaneously target CD3 and an undisclosed tumor target for the potential treatment of various hematological malignancies and solid tumors. The transaction closed in June 2016, and the Company received the $75.0 million upfront payment from Janssen in July 2016. Under the collaboration and license agreement, the Company granted an exclusive license to Janssen to develop and commercialize MGD015. Janssen will complete the IND-enabling activities and will be fully responsible for the future clinical development and commercialization of MGD015. Assuming successful development and commercialization, the agreement entitles the Company to receive up to $100.0 million in development milestone payments, $265.0 million in regulatory milestone payments and $300.0 million in sales milestone payments. The Company determined that each potential future clinical and regulatory milestone is substantive. Although the sales milestones are not considered substantive, they will be recognized upon achievement of the milestone (assuming all other revenue recognition criteria have been met) because there are no undelivered elements that would preclude revenue recognition at that time. The Company may elect to fund a portion of late-stage clinical development in exchange for a profit share with Janssen in the U.S. and Canada. If commercialized, the Company would be eligible to receive low double-digit royalties on any global net sales and has the option to co-promote the molecule with Janssen in the United States. The Company evaluated the collaboration and license agreement with Janssen and determined that it is a revenue arrangement with multiple deliverables, or performance obligations. The Company's substantive performance obligations under the collaboration and license agreement include the delivery of an exclusive license and research and development services during the preclinical research period. The Company evaluated the collaboration and license agreement with Janssen and determined that the license and preclinical research and development activities each represented separate deliverables and were accounted for as two separate units of accounting. The Company concluded that the license had standalone value to Janssen and was separable from the research and development services because the license was sublicensable, there were no restrictions as to Janssen's use of the license and Janssen or other third parties have significant research capabilities in this field. Thus, the total arrangement consideration for these two deliverables was allocated using the best estimate of relative selling price method to each deliverable. The best estimate of selling price for the exclusive license was determined using information from the previous collaboration and license agreement with Janssen as well as other third party collaboration and license agreements, which are Level 2 fair value measurements. The best estimate of selling price for the research and development services was determined using other similar research and development arrangements, which are also Level 2 fair value measurements. During the three months ended June 30, 2016, the Company recognized revenues of $75.0 million under the agreement. Takeda Pharmaceutical Company Limited In May 2014, the Company entered into a license and option agreement with Takeda Pharmaceutical Company Limited (Takeda) for the development and commercialization of MGD010, a product candidate that incorporates the Company's proprietary DART technology to simultaneously engage CD32B and CD79B, which are two B-cell surface proteins. MGD010 is being developed for the treatment of autoimmune disorders. Upon execution of the agreement, Takeda made a non-refundable payment of $15.0 million to the Company. Takeda has an option to obtain an exclusive worldwide license for MGD010 following the completion of a pre-defined Phase 1a study. The Company will lead all product development activities until that time. If Takeda exercises its option, it will assume responsibility for future development and pay the Company a license fee of $15.0 million. Assuming successful development and commercialization of MGD010, the Company is eligible to receive up to $93.0 million in clinical and regulatory milestone payments and $375.5 million in sales milestone payments. If commercialized, the Company would receive low double-digit to high-teen royalties on any global net sales and has the option to co-promote MGD010 with Takeda in the United States. Finally, the Company may elect to fund a portion of Phase 3 clinical development in exchange for a North American profit share. The Company evaluated the license and option agreement with Takeda and has determined that it is a revenue arrangement with multiple deliverables, or performance obligations. The Company's substantive performance obligations under the license and option agreement include exclusivity, research and development services through the Phase 1a study and delivery of a future license for an initial research compound. The Company concluded that the MGD010 option is substantive and that the license fee payable upon exercise of the option is not a deliverable at the inception of the arrangement as there is considerable uncertainty that the option would be exercised. The Company determined that each potential future clinical and regulatory milestone is substantive. Although sales milestones are not considered substantive, they are still recognized upon achievement of the milestone (assuming all other revenue recognition criteria have been met) because there are no undelivered elements that would preclude revenue recognition at that time. The Company determined that these performance obligations represent a single unit of accounting, because the exclusivity clause does not have stand-alone value to Takeda without the Company's technical expertise and development through the pre-defined Phase 1a study. After identifying the deliverables included within the arrangement, the Company determined its best estimate of selling price. The Company allocated $10.0 million to the exclusivity clause to its technology and the research and development services and $5.0 million to the exclusive license for the initial research compound. The Company's determination of best estimate of selling price for the research and development services relied upon other similar transactions. The Company relied upon the income approach (e.g., discounted future cash flows) to determine the value of the license of the to-be-delivered compound along with other similar license transactions with differing indications but similar stage of development. The portion of the up-front fee allocated to the MGD010 option was being recognized over an initial 24-month period, which represented the expected period of development through the completion of a pre-defined Phase 1a study. During the first quarter of 2016, the Company determined that the development period will be extended by eight months, and prospectively adjusted the MGD010 option fee recognition period. The portion of the up-front fee allocated to the license for the initial research compound was deferred until the research collaboration and license option agreement was executed and the license delivered in September 2014. The Company recognized revenue of approximately $0.3 million and $1.2 million under the MGD010 agreement during the three months ended June 30, 2016 and 2015, respectively. The Company recognized revenue of approximately $1.3 million and $5.5 million under the MGD010 agreement during the six months ended June 30, 2016 and 2015, respectively. Revenue recognized during the six months ended June 30, 2015, included a $3.0 million milestone payment received upon initiation of a Phase 1a trial of MGD010. At June 30, 2016, $0.8 million of revenue was deferred under this agreement, all of which was current. At December 31, 2015, $2.1 million of revenue was deferred under this agreement, all of which was current. In September 2014, the Company and Takeda executed a research collaboration and license option agreement, which formalized the license for the initial research compound contemplated in the May 2014 arrangement. Under the terms of the agreement, Takeda may identify up to three additional compounds, which will be subject to separate research and development plans. The Company determined that it could recognize the entire license fee allocated to this agreement as (1) the executed contract constituted persuasive evidence of an arrangement, (2) the delivery of the license occurred and the Company had no current or future performance obligations, (3) the total consideration for the license was fixed and known at the time of its execution and there were not any extended payment terms or rights of return, and (4) the cash was received. The Company is also entitled to receive reimbursements for research and development services provided to Takeda with respect to the initial research compound under a separate research plan. The Company recognized revenue of approximately $0.4 million and $0.7 million under this agreement during the three and six months ended June 30, 2015, respectively. Takeda terminated its option to license the first program under this research collaboration agreement in 2015 and retains an option for three others. Les Laboratoires Servier In September 2012, the Company entered into a right-to-develop collaboration agreement with Les Laboratoires Servier and Institut de Recherches Servier (collectively, Servier) and granted it options to obtain three separate exclusive licenses to develop and commercialize DART molecules, consisting of those designated by the Company as MGD006 (also known as S80880) and MGD007, as well as a third DART molecule, in all countries other than the United States, Canada, Mexico, Japan, South Korea and India. Upon execution of the agreement, Servier made a nonrefundable payment of $20.0 million to the Company. In addition, the Company will be eligible to receive up to $65.0 million in license fees, $98.0 million in clinical milestone payments, including $5.0 million upon IND acceptance for each of MGD006, MGD007 and a third DART molecule, $300.0 million in regulatory milestone payments and $630.0 million in sales milestone payments if Servier exercises all of the options and successfully develops, obtains regulatory approval for, and commercializes a product under each license. In addition to these milestones, the Company and Servier will share Phase 2 and Phase 3 development costs. The Company has determined that each potential future clinical and regulatory milestone is substantive. Although sales milestones are not considered substantive, they are still recognized upon achievement of the milestone (assuming all other revenue recognition criteria have been met) because there are no undelivered elements that would preclude revenue recognition at that time. Under this agreement, Servier would be obligated to pay the Company from low double-digit to mid-teen royalties on net product sales in its territories. The Company evaluated the research collaboration agreement with Servier and determined that it is a revenue arrangement with multiple deliverables, or performance obligations. The Company concluded that each option is substantive and that the license fees for each option are not deliverables at the inception of the arrangement and were not issued with a substantial discount. The Company's substantive performance obligations under this research collaboration include an exclusivity clause to its technology, technical, scientific and intellectual property support to the research plan and participation on an executive committee and a research and development committee. The Company determined that the performance obligations with respect to the preclinical development represent a single unit of accounting, since the license does not have stand-alone value to Servier without the Company's technical expertise and committee participation. As such, the initial upfront license payment was deferred and initially recognized ratably over a 29-month period, which represented the expected development period. During 2014, the Company and Servier further refined the research plan related to the three DART molecules and as such, the development period was extended. Based on this revised development period, the Company prospectively adjusted its period of recognition of the upfront payment to a 75-month period. During 2014, Servier exercised its exclusive option to develop and commercialize MGD006. As a result of the exercise, the Company received a $15.0 million payment from Servier for its license to develop and commercialize MGD006 in its territories. Upon exercise of the option, the Company evaluated its performance obligations with respect to the license for MGD006. The Company's substantive performance obligations under this research collaboration include an exclusive license to its technology, technical, scientific and intellectual property support to the research plan and participation on an executive committee and a research and development committee. The Company determined that the performance obligations with respect to the clinical development represent a single unit of accounting, since the license does not have stand-alone value to Servier without the Company's technical expertise and committee participation. As such, the $15.0 million license fee was deferred and is being recognized ratably over a period of 82 months, which represents the expected development period for MGD006. In accordance with the agreement, the Company and Servier will share costs incurred to develop MGD006. Reimbursement of research and development expenses received in connection with this collaborative cost-sharing agreement is recorded as a reduction to research and development expense. During the three months ended June 30, 2016 and 2015, the Company recorded approximately $0.7 million and $0.2 million as an offset to research and development costs under this collaboration arrangement, respectively. During the six months ended June 30, 2016 and 2015, the Company recorded approximately $1.1 million and $0.5 million as an offset to research and development costs under this collaboration arrangement, respectively. The Company recognized revenue under this agreement of $0.8 million and $1.0 million during the three months ended June 30, 2016 and 2015, respectively. The Company recognized revenue under this agreement of $1.7 million and $1.8 million during the six months ended June 30, 2016 and 2015, respectively. At June 30, 2016, $12.7 million of revenue was deferred under this agreement, $3.3 million of which was current and $9.4 million of which was non-current. At December 31, 2015, $14.4 million of revenue was deferred under this agreement, $3.3 million of which was current and $11.1 million of which was non-current. Green Cross Corporation In June 2010, the Company entered into a collaboration agreement with Green Cross Corporation (Green Cross) for the development of the Company's anti-HER2 antibody margetuximab. This arrangement grants Green Cross an exclusive license to conduct specified Phase 1 and Phase 2 clinical trials and commercialize margetuximab in South Korea. In March 2014, the Company and Green Cross entered into an amendment to the original agreement, causing the terms of the original agreement to be materially modified. Upon execution of the amendment, the Company became eligible to receive reimbursement for costs incurred for Phase 2 and Phase 3 clinical trials up to $5.5 million as well as clinical development and commercial milestone payments of up to $2.5 million. The Company determined that each potential clinical development and commercial milestone is substantive. The Company is also entitled to receive royalties on net sales of margetuximab in South Korea. The Company and Green Cross have formed a joint steering committee to coordinate and oversee activities on which the companies collaborate under the agreement. The Company evaluated the collaboration agreement with Green Cross and determined that it is a revenue arrangement with multiple deliverables or performance obligations. As a result of the material modification to the arrangement in March 2014, the Company reassessed the entire arrangement in accordance with the guidance provided by ASC 605-25, Multiple Element Arrangements (Revenue Recognition) . The initial $1.0 million upfront payment received by the Company upon execution of the original agreement is non-refundable; as such, there is no right of return for the license. Therefore, the upfront license fee and participation on the joint steering committee were treated as a combined unit of accounting and is being recognized over the term of the agreement through June 2020. Further, due to the fact the research and development services are not deemed to have stand-alone value, revenue for those services will be recognized over the entire term of the agreement (through June 2020). As a result of reassessing the arrangement in accordance with ASC 605-25, the Company was required to record an adjustment on the date of the material modification to reflect the revenue that would have resulted had the entity applied the requirements of ASC 605-25 from the inception of the agreement. As a result, the Company recorded an additional $1.3 million of revenue during 2014. The Company recognized revenues of approximately $0.1 million during each of the three-month periods ended June 30, 2016 and 2015 under this agreement. The Company recognized revenues of approximately $0.2 million during each of the six-month periods ended June 30, 2016 and 2015 under this agreement. At June 30, 2016, $1.8 million of revenue was deferred under this agreement, $0.4 million of which was current and $1.4 million of which was non-current. At December 31, 2015, $2.0 million of revenue was deferred under this agreement, $0.4 million of which was current and $1.6 million of which was non-current. NIAID Contract The Company entered into a contract with the National Institute of Allergy and Infectious Diseases (NIAID), effective as of September 2015, to perform product development and to advance up to two DART molecules, including MGD014. Under this contract, the Company will develop these product candidates for Phase 1/2 clinical trials as therapeutic agents, in combination with latency reversing treatments, to deplete cells infected with human immunodeficiency virus (HIV) infection. This contract includes a base period of $7.5 million to support development of MGD014 through IND application submission with the FDA, as well as up to $17.0 million in additional development funding via NIAID options. Should NIAID fully exercise such options, the Company could receive total payments of up to $24.5 million. The total potential period of performance under the award is from September 15, 2015 through September 14, 2022. The Company recognized $2.2 million and $3.1 million in revenue under this contract during the three and six months ended June 30, 2016, respectively.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2016
Stock-Based Compensation [Abstract]
Stock-Based Compensation	6. Stock-Based Compensation Under the provisions of the Company's 2013 Stock Incentive Plan (2013 Plan), the number of shares of common stock reserved for issuance will automatically increase on January 1 of each year from January 1, 2014 through and including January 1, 2023, by the lesser of (a) 1,960,168 shares, (b) 4.0 % of the total number of shares of common stock outstanding on December 31 of the preceding calendar year, or (c) the number of shares of common stock determined by the Board of Directors. During the six months ended June 30, 2016, the maximum number of shares of common stock authorized to be issued by the Company under the 2013 Plan was increased to 5,375,064. As of June 30, 2016, there were options to purchase an aggregate of 2,587,788 shares of common stock outstanding at a weighted average exercise price of $26.32 per share under the 2013 Plan. The following stock-based compensation amounts were recognized for the periods indicated (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Research and development $ 1,445 $ 881 $ 2,841 $ 1,691 General and administrative 1,678 1,021 3,283 1,842 Total stock-based compensation expense $ 3,123 $ 1,902 $ 6,124 $ 3,533 Employee Stock Options The fair value of each option award is estimated on the date of grant using the Black-Scholes option-pricing model using the assumptions in the following table: Six Months Ended June 30, 2016 2015 Expected dividend yield 0% 0% Expected volatility 63.7 % - 65.4 % 74 % Risk-free interest rate 1.3% - 2.1% 1.6% - 2.1% Expected term 6.25 years 6.25 years The following table summarizes stock option and restricted stock unit (RSU) activity during the six months ended June 30, 2016: Shares Weighted- Weighted-Average Aggregate Outstanding, December 31, 2015 4,146,064 $ 16.90 7.4 Granted 206,174 17.60 Exercised (350,147 ) 1.12 Forfeited or expired (94,538 ) 28.70 Outstanding, June 30, 2016 3,907,553 18.06 7.4 $ 41,198 As of June 30, 2016: Exercisable 2,076,701 11.75 6.2 33,306 Vested and expected to vest 3,689,857 17.71 7.3 40,055 The weighted-average grant-date fair value of options granted for the six months ended June 30, 2016 was $12.78. The total intrinsic value of options exercised during the six months ended June 30, 2016 was approximately $7.2 million, and the total cash received for options exercised was approximately $0.4 million. The total fair value of shares vested in the six months ended June 30, 2016 was approximately $6.0 million. As of June 30, 2016, the total unrecognized compensation expense related to non-vested stock options, net of related forfeiture estimates, was approximately $25.8 million, which the Company expects to recognize over a weighted-average period of approximately three years.

Net Income (Loss) Per Share

Net Income (Loss) Per Share	6 Months Ended
	Jun. 30, 2016
Net Income (Loss) Per Share [Abstract]
Net Income (Loss) Per Share	7. Net Income (Loss) Per Share Basic income (loss) per common share is determined by dividing income (loss) attributable to common stockholders by the weighted-average number of common shares outstanding during the period, without consideration of common stock equivalents. Diluted income (loss) per share is computed by dividing the income (loss) attributable to common stockholders by the weighted-average number of common stock equivalents outstanding for the period. The treasury stock method is used to determine the dilutive effect of the Company's stock option grants. 257,678 and 2,020,204 stock options (common stock equivalents) were excluded from the calculation of diluted income (loss) per share for the three months ended June 30, 2016 and 2015, respectively, because their inclusion would have been anti-dilutive. 114,148 and 738,882 stock options were excluded from the calculation of diluted income per share for the six months ended June 30, 2016 and 2015, respectively, because their inclusion would have been anti-dilutive. Basic and diluted income (loss) per common share is computed as follows (in thousands except share and per share data): Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Numerator: Net income (loss) used for calculation of basic and diluted EPS $ 40,464 $ (21,376 ) $ 10,101 $ 23,753 Denominator: Weighted average shares outstanding, basic 34,616,197 30,059,329 34,560,021 29,739,326 Effect of dilutive securities: Stock options and restricted stock units 1,401,214 - 1,406,966 2,058,006 Weighted average shares outstanding, diluted 36,017,411 30,059,329 35,966,987 31,797,332 Net income (loss) per share, basic $ $1.17 $ ($0.71 ) $ $0.29 $ $0.80 Net income (loss) per share, diluted $ $1.12 $ ($0.71 ) $ $0.28 $ $0.75

Basis of Presentation and Rec13

Basis of Presentation and Recently Issued Accounting Standards (Policies)	6 Months Ended
	Jun. 30, 2016
Basis of Presentation and Recently Issued Accounting Standards
Basis of Presentation	1. Basis of Presentation and Recently Issued Accounting Standards Basis of Presentation The accompanying unaudited interim consolidated financial statements of MacroGenics, Inc. (the Company) have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information. The financial statements include all adjustments (consisting only of normal recurring adjustments) that the management of the Company believes are necessary for a fair presentation of the periods presented. These interim financial results are not necessarily indicative of results expected for the full fiscal year or for any subsequent interim period. The accompanying unaudited interim consolidated financial statements include the accounts of MacroGenics, Inc. and its wholly owned subsidiary, MacroGenics UK Limited. All intercompany accounts and transactions have been eliminated in consolidation. These consolidated financial statements and related notes should be read in conjunction with the financial statements and notes thereto included in the Company's 2015 Annual Report on Form 10-K filed with the Securities and Exchange Commission (SEC) on February 29, 2016. There have been no material changes to the significant accounting policies previously disclosed in the Company's 2015 Annual Report on Form 10-K other than the adoption of ASU No. 2015-17, Income Taxes, Balance Sheet Classification of Deferred Taxes,

Fair Value of Financial Instr14

Fair Value of Financial Instruments (Tables)	6 Months Ended
	Jun. 30, 2016
Fair Value of Financial Instruments [Abstract]
Financial Assets Measured at Fair Value on a Recurring Basis	Financial assets measured at fair value on a recurring basis were as follows (in thousands): Fair Value Measurements at June 30, 2016 Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Total Level 1 Level 2 Level 3 Assets: Money market funds $ 47,713 $ 47,713 $ – $ – U.S. Treasury securities 5,263 – 5,263 – Government-sponsored enterprises 29,121 – 29,121 – Corporate debt securities 168,973 – 168,973 – Total assets measured at fair value (a) $ 251,070 $ 47,713 $ 203,357 $ – (a) Total assets measured at fair value at June 30, 2016, includes approximately $47.7 million reported in cash and cash equivalents on the balance sheet. Fair Value Measurements at December 31, 2015 Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Total Level 1 Level 2 Level 3 Assets: Money market funds $ 62,353 $ 62,353 $ – $ – U.S. Treasury securities 9,349 – 9,349 – Government-sponsored enterprises 41,202 – 41,202 – Corporate debt securities 137,928 – 137,928 – Total assets measured at fair value (a) $ 250,832 $ 62,353 $ 188,479 $ – (a) Total assets measured at fair value at December 31, 2015, includes approximately $108.0 million reported in cash and cash equivalents on the balance sheet.

Investments (Tables)

Investments (Tables)	6 Months Ended
	Jun. 30, 2016
Investments [Abstract]
Available-for-sale Securities	Available-for-sale investments as of June 30, 2016 and December 31, 2015 were as follows (in thousands): June 30, 2016 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury securities $ 5,262 $ 1 $ - $ 5,263 Government-sponsored enterprises 29,109 12 - 29,121 Corporate debt securities 168,927 81 (35 ) 168,973 Total $ 203,298 $ 94 $ (35 ) $ 203,357 December 31, 2015 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S. Treasury securities $ 9,354 $ 1 $ (6 ) $ 9,349 Government-sponsored enterprises 22,055 1 (9 ) 22,047 Corporate debt securities 111,473 42 (34 ) 111,481 Total $ 142,882 $ 44 $ (49 ) $ 142,877

Lease Exit Liability (Tables)

Lease Exit Liability (Tables)	6 Months Ended
	Jun. 30, 2016
Lease Exit Liability [Abstract]
Changes in Lease Exit Liability	Changes in the lease exit liability are as follows (in thousands): Accrual balance at December 31, 2015 $ 4,713 Principal payments and other adjustments (2,134 ) Accrual balance at June 30, 2016 $ 2,579

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2016
Stock-Based Compensation [Abstract]
Stock-Based Compensation Expense	The following stock-based compensation amounts were recognized for the periods indicated (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Research and development $ 1,445 $ 881 $ 2,841 $ 1,691 General and administrative 1,678 1,021 3,283 1,842 Total stock-based compensation expense $ 3,123 $ 1,902 $ 6,124 $ 3,533
Valuation Assumptions Using the Black-Scholes Option-Pricing Model	The fair value of each option award is estimated on the date of grant using the Black-Scholes option-pricing model using the assumptions in the following table: Six Months Ended June 30, 2016 2015 Expected dividend yield 0% 0% Expected volatility 63.7 % - 65.4 % 74 % Risk-free interest rate 1.3% - 2.1% 1.6% - 2.1% Expected term 6.25 years 6.25 years
Stock Option Activity	The following table summarizes stock option and restricted stock unit (RSU) activity during the six months ended June 30, 2016: Shares Weighted- Weighted-Average Aggregate Outstanding, December 31, 2015 4,146,064 $ 16.90 7.4 Granted 206,174 17.60 Exercised (350,147 ) 1.12 Forfeited or expired (94,538 ) 28.70 Outstanding, June 30, 2016 3,907,553 18.06 7.4 $ 41,198 As of June 30, 2016: Exercisable 2,076,701 11.75 6.2 33,306 Vested and expected to vest 3,689,857 17.71 7.3 40,055

Net Income (Loss) Per Share (Ta

Net Income (Loss) Per Share (Tables)	6 Months Ended
	Jun. 30, 2016
Net Income (Loss) Per Share [Abstract]
Computation of Basic and Diluted Income (Loss) Per Common Share	Basic and diluted income (loss) per common share is computed as follows (in thousands except share and per share data): Three Months Ended June 30, Six Months Ended June 30, 2016 2015 2016 2015 Numerator: Net income (loss) used for calculation of basic and diluted EPS $ 40,464 $ (21,376 ) $ 10,101 $ 23,753 Denominator: Weighted average shares outstanding, basic 34,616,197 30,059,329 34,560,021 29,739,326 Effect of dilutive securities: Stock options and restricted stock units 1,401,214 - 1,406,966 2,058,006 Weighted average shares outstanding, diluted 36,017,411 30,059,329 35,966,987 31,797,332 Net income (loss) per share, basic $ $1.17 $ ($0.71 ) $ $0.29 $ $0.80 Net income (loss) per share, diluted $ $1.12 $ ($0.71 ) $ $0.28 $ $0.75

Fair Value of Financial Instr19

Fair Value of Financial Instruments (Details) - Fair Value Measured on a Recurring Basis [Member] - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Assets:
Cash and cash equivalents	$ 47,700	$ 108,000
Total Assets	251,070	250,832
Money Market Funds [Member]
Assets:
Cash and cash equivalents	47,713	62,353
U.S. Treasury Securities [Member]
Assets:
Available-for-sale securities	5,263	9,349
Government-sponsored Enterprises [Member]
Assets:
Available-for-sale securities	29,121	41,202
Corporate Debt Securities [Member]
Assets:
Available-for-sale securities	168,973	137,928
Quoted Prices in Active Markets for Identical Assets Level 1 [Member]
Assets:
Total Assets	47,713	62,353
Quoted Prices in Active Markets for Identical Assets Level 1 [Member] | Money Market Funds [Member]
Assets:
Cash and cash equivalents	47,713	62,353
Quoted Prices in Active Markets for Identical Assets Level 1 [Member] | U.S. Treasury Securities [Member]
Assets:
Available-for-sale securities	0	0
Quoted Prices in Active Markets for Identical Assets Level 1 [Member] | Government-sponsored Enterprises [Member]
Assets:
Available-for-sale securities	0	0
Quoted Prices in Active Markets for Identical Assets Level 1 [Member] | Corporate Debt Securities [Member]
Assets:
Available-for-sale securities	0	0
Quoted Prices in Active Markets for Identical Assets Level 2 [Member]
Assets:
Total Assets	203,357	188,479
Quoted Prices in Active Markets for Identical Assets Level 2 [Member] | Money Market Funds [Member]
Assets:
Cash and cash equivalents	0	0
Quoted Prices in Active Markets for Identical Assets Level 2 [Member] | U.S. Treasury Securities [Member]
Assets:
Available-for-sale securities	5,263	9,349
Quoted Prices in Active Markets for Identical Assets Level 2 [Member] | Government-sponsored Enterprises [Member]
Assets:
Available-for-sale securities	29,121	41,202
Quoted Prices in Active Markets for Identical Assets Level 2 [Member] | Corporate Debt Securities [Member]
Assets:
Available-for-sale securities	168,973	137,928
Quoted Prices in Active Markets for Identical Assets Level 3 [Member]
Assets:
Total Assets	0	0
Quoted Prices in Active Markets for Identical Assets Level 3 [Member] | Money Market Funds [Member]
Assets:
Cash and cash equivalents	0	0
Quoted Prices in Active Markets for Identical Assets Level 3 [Member] | U.S. Treasury Securities [Member]
Assets:
Available-for-sale securities	0	0
Quoted Prices in Active Markets for Identical Assets Level 3 [Member] | Government-sponsored Enterprises [Member]
Assets:
Available-for-sale securities	0	0
Quoted Prices in Active Markets for Identical Assets Level 3 [Member] | Corporate Debt Securities [Member]
Assets:
Available-for-sale securities	$ 0	$ 0

Investments (Details)

Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	$ 203,298	$ 142,882
Gross unrealized gains	94	44
Gross unrealized losses	(35)	(49)
Fair value	203,357	142,877
Government-sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	29,109	22,055
Gross unrealized gains	12	1
Gross unrealized losses	0	(9)
Fair value	29,121	22,047
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	168,927	111,473
Gross unrealized gains	81	42
Gross unrealized losses	(35)	(34)
Fair value	168,973	111,481
U.S. Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	5,262	9,354
Gross unrealized gains	1	1
Gross unrealized losses	0	(6)
Fair value	$ 5,263	$ 9,349

Lease Exit Liability (Details)

Lease Exit Liability (Details) - USD ($) $ in Thousands	Jul. 16, 2008	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016
Restructuring Cost and Reserve [Line Items]
Lease expiration date	2018-02
Restructuring Costs [Abstract]
Potential future payment under purchase agreement	$ 5,000
Incremental in-process research and development expense		$ 0	$ 0
Operating Leases, Future Minimum Payments Due, Future Minimum Sublease Rentals		1,300		$ 1,300
Reduction in R&D expense		1,300
Minimum [Member]
Restructuring Costs [Abstract]
Potential payment under license of product	8,000
Maximum [Member]
Restructuring Costs [Abstract]
Potential payment under license of product	$ 12,000
Contract Termination [Member]
Restructuring Costs [Abstract]
Accrual beginning balance				4,713
Principal payments				(2,134)
Accrual balance at June 30, 2016		$ 2,579		$ 2,579

Collaboration and Other Agree22

Collaboration and Other Agreements, Janssen Biotech, Inc. (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended	6 Months Ended
	Jan. 31, 2015	Jun. 30, 2016	Jun. 30, 2016	Jun. 30, 2015	Jul. 31, 2015
Janssen MGD011 Agreement [Member] | Maximum [Member]
Collaboration and Other Agreements [Line Items]
Additional Potential Development Milestone Payments Under Agreement		$ 205	$ 205
Janssen MGD015 Agreement [Member] | Maximum [Member]
Collaboration and Other Agreements [Line Items]
Additional Potential Development Milestone Payments Under Agreement		100	100
Janssen Biotech, Inc. [Member]
Collaboration and Other Agreements [Line Items]
Recognized revenue under agreement			$ 0
Janssen Biotech, Inc. [Member] | Janssen MGD011 Agreement [Member]
Collaboration and Other Agreements [Line Items]
Collaboration or other agreement date			December 2,014
Sale of common stock (in shares)	1,923,077
Proceeds of stock sale	$ 75
Sale of common stock (in dollars per share)	$ 39
Premium received on stock purchase	$ 12.3
Total consideration	125
Amount allocated to equity	62.7
Amount allocated to license and R&D	62.3
Clinical milestone earned during period					$ 10
Recognized revenue under agreement		0		$ 62.3
Non-refundable upfront payment	$ 50
Janssen Biotech, Inc. [Member] | Janssen MGD011 Agreement [Member] | Maximum [Member]
Collaboration and Other Agreements [Line Items]
Potential regulatory milestone payments under agreement		220	$ 220
Potential sales milestone payments under agreement		150	$ 150
Janssen Biotech, Inc. [Member] | Janssen MGD015 Agreement [Member]
Collaboration and Other Agreements [Line Items]
Collaboration or other agreement date			May 2,016
Recognized revenue under agreement		75
Non-refundable upfront payment		75
Janssen Biotech, Inc. [Member] | Janssen MGD015 Agreement [Member] | Maximum [Member]
Collaboration and Other Agreements [Line Items]
Potential regulatory milestone payments under agreement		265	$ 265
Potential sales milestone payments under agreement		$ 300	$ 300

Collaboration and Other Agree23

Collaboration and Other Agreements, Takeda (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	May 31, 2014	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Collaboration And Other Agreements [Line Items]
Deferred revenue included in current liabilities		$ 4,578		$ 4,578		$ 5,866
Deferred revenue included in long-term liabilities		10,740		$ 10,740		12,631
Takeda Pharmaceutical Company Limited [Member]
Collaboration And Other Agreements [Line Items]
Non-refundable upfront payment	$ 15,000
Takeda Pharmaceutical Company Limited [Member] | Research Collaboration And License Option Agreement [Member]
Collaboration And Other Agreements [Line Items]
Collaboration or other agreement date				September 2,014
Amount allocated to agreement	5,000
Recognized revenue under agreement			$ 400		$ 700
Takeda Pharmaceutical Company Limited [Member] | Takeda MGD010 Agreement [Member]
Collaboration And Other Agreements [Line Items]
Collaboration or other agreement date				May 2,014
License option fee		15,000		$ 15,000
Amount allocated to agreement	$ 10,000
Expected period of development				24 months
Recognized revenue under agreement		300	$ 1,200	$ 1,300	5,500
Milestone received					$ 3,000
Deferred revenue		800		800		2,100
Deferred revenue included in current liabilities		800		800		$ 2,100
Takeda Pharmaceutical Company Limited [Member] | Takeda MGD010 Agreement [Member] | Maximum [Member]
Collaboration And Other Agreements [Line Items]
Potential clinical and regulatory milestone payments		93,000		93,000
Potential sales milestone payments under agreement		$ 375,500		$ 375,500

Collaboration and Other Agree24

Collaboration and Other Agreements, Servier (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Sep. 30, 2012	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015	Dec. 31, 2014
Collaboration And Other Agreements [Line Items]
Deferred revenue included in current liabilities		$ 4,578		$ 4,578		$ 5,866
Deferred revenue included in long-term liabilities		10,740		$ 10,740		12,631
Servier [Member] | Servier DART [Member]
Collaboration And Other Agreements [Line Items]
Collaboration or other agreement date				September 2,012
Non-refundable upfront payment	$ 20,000
Original period of development				29 months
Expected period of development				75 months
Option exercise fee							$ 15,000
Option exercise fee recognition period				82 months
Offset to research and development costs under collaboration arrangement		700	$ 200	$ 1,100	$ 500
Recognized revenue under agreement		800	$ 1,000	1,700	$ 1,800
Deferred revenue		12,700		12,700		14,400
Deferred revenue included in current liabilities		3,300		3,300		3,300
Deferred revenue included in long-term liabilities		9,400		9,400		$ 11,100
Servier [Member] | Servier DART [Member] | Maximum [Member]
Collaboration And Other Agreements [Line Items]
Potential license fee		65,000		65,000
Potential clinical milestone payments		98,000		98,000
Potential regulatory milestone payments under agreement		300,000		300,000
Potential sales milestone payments under agreement		630,000		630,000
Additional Potential Milestone Payments Receivable Upon New Drug Application Acceptance		$ 5,000		$ 5,000

Collaboration and Other Agree25

Collaboration and Other Agreements, Green Cross (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2010	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2014	Dec. 31, 2015
Collaboration And Other Agreements [Line Items]
Deferred revenue included in current liabilities		$ 4,578		$ 4,578			$ 5,866
Deferred revenue included in long-term liabilities		10,740		$ 10,740			12,631
Green Cross [Member]
Collaboration And Other Agreements [Line Items]
Collaboration or other agreement date				June 2,010
Non-refundable upfront payment	$ 1,000
Term of the agreement				June 2,020
Adjustment to revenue from contract material modification						$ 1,300
Recognized revenue under agreement		100	$ 100	$ 200	$ 200
Deferred revenue		1,800		1,800			2,000
Deferred revenue included in current liabilities		400		400			400
Deferred revenue included in long-term liabilities		1,400		1,400			$ 1,600
Green Cross [Member] | Maximum [Member]
Collaboration And Other Agreements [Line Items]
Aggregate potential future cost reimbursement		5,500		5,500
Clinical and commercial milestone payments		$ 2,500		$ 2,500

Collaboration and Other Agree26

Collaboration and Other Agreements, NIAID Contract (Details) - NIAID [Member] $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2016USD ($)	Jun. 30, 2016USD ($)Molecule
Collaboration And Other Agreements [Line Items]
Collaboration or other agreement date		September 15, 2015
Commercialization of molecules | Molecule		2
Base period value	$ 7.5	$ 7.5
Agreement end date		September 14, 2022
Recognized revenue under agreement	2.2	$ 3.1
Maximum [Member]
Collaboration And Other Agreements [Line Items]
Additional development funding options	17	17
Total potential value	$ 24.5	$ 24.5

Stock-Based Compensation, Stock

Stock-Based Compensation, Stock-Based Compensation Expense (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	3,907,553		3,907,553		4,146,064
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 18.06		$ 18.06		$ 16.90
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 3,123	$ 1,902	$ 6,124	$ 3,533
2013 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, number of shares authorized (in shares)	5,375,064		5,375,064
Potential annual increase in shares reserved for future issuance	1,960,168		1,960,168
Potential annual increase in shares reserved for future issuance as percentage of outstanding share	4.00%		4.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	2,587,788		2,587,788
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 26.32		$ 26.32
Research and Development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 1,445	881	$ 2,841	1,691
General and Administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 1,678	$ 1,021	$ 3,283	$ 1,842

Stock-Based Compensation, Optio

Stock-Based Compensation, Option Pricing Assumptions (Details)	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	0.00%	0.00%
Expected volatility		74.00%
Expected term	6 years 3 months	6 years 3 months
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	63.70%
Risk-free interest rate	1.30%	1.60%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	65.40%
Risk-free interest rate	2.10%	2.10%

Stock-Based Compensation, Sto29

Stock-Based Compensation, Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Stock-Based Compensation [Abstract]
Shares, Outstanding, Beginning Balance (in shares)	4,146,064
Shares, Granted (in shares)	206,174
Shares, Exercised (in shares)	(350,147)
Shares, Forfeited or expired (in shares)	(94,538)
Shares, Outstanding, Ending Balance (in shares)	3,907,553		4,146,064
Shares, Exercisable (in shares)	2,076,701
Shares, Vested and expected to vest (in shares)	3,689,857
Weighted- Average Exercise Price, Outstanding, Beginning Balance (in dollars per share)	$ 16.90
Weighted- Average Exercise Price, Granted (in dollars per share)	17.60
Weighted- Average Exercise Price, Exercised (in dollars per share)	1.12
Weighted- Average Exercise Price, Forfeited or expired (in dollars per share)	28.70
Weighted- Average Exercise Price, Outstanding, Ending Balance (in dollars per share)	18.06		$ 16.90
Weighted- Average Exercise Price, Exercisable (in dollars per share)	11.75
Weighted- Average Exercise Price, Vested and expected to vest (in dollars per share)	$ 17.71
Weighted- Average Remaining Contractual Term, Outstanding	7 years 4 months 24 days		7 years 4 months 24 days
Weighted- Average Remaining Contractual Term, Exercisable	6 years 2 months 12 days
Weighted- Average Remaining Contractual Term, Vested and expected to vest	7 years 3 months 18 days
Aggregate Intrinsic Value, Outstanding, Ending Balance	$ 41,198
Aggregate Intrinsic Value, Exercisable	33,306
Aggregate Intrinsic Value, Vested and expected to vest	$ 40,055
Weighted-average grant-date fair value of options granted (in dollars per share)	$ 12.78
Intrinsic value of options exercised	$ 7,200
Cash received for options exercised	351	$ 425
Fair value of shares vested	6,000
Unrecognized compensation expense related to non-vested stock-options, net of related forfeiture estimates	$ 25,800
Unrecognized compensation expense recognition period	3 years

Net Income (Loss) Per Share (De

Net Income (Loss) Per Share (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Net Income (Loss) Per Share [Abstract]
Net income (loss) used for calculation of basic and diluted EPS	$ 40,464,000	$ (21,376,000)	$ 10,101,000	$ 23,753,000
Basic weighted average number of common shares (in shares)	34,616,197	30,059,329	34,560,021	29,739,326
Net income (loss) per share, basic	$ 1.17	$ (0.71)	$ 0.29	$ 0.80
Basic weighted average common shares outstanding (in shares)	34,616,197	30,059,329	34,560,021	29,739,326
Stock options and restricted stock units (in shares)	1,401,214	0	1,406,966	2,058,006
Weighted average shares outstanding, diluted	36,017,411	30,059,329	35,966,987	31,797,332
Diluted income (loss) per common share (in dollars per share)	$ 1.12	$ (0.71)	$ 0.28	$ 0.75
Stock options excluded from diluted EPS (in shares)	257,678	2,020,204	114,148	738,882