MacroGenics Advances Two First-in-Class Clinical DART® Molecules

• First patient dosed with MGD013 (PD-1 x LAG-3 DART)
• IND submitted for MGD014 (HIV x CD3 DART)
• NIAID exercises option to advance MGD014 and develop second HIV-directed DART molecule

ROCKVILLE, MD, Sept. 05, 2017 --  MacroGenics, Inc. (Nasdaq: MGNX), a clinical-stage biopharmaceutical company focused on discovering and developing innovative monoclonal antibody-based therapeutics for the treatment of cancer, as well as autoimmune disorders and infectious diseases, today announced the advancement of two of its proprietary bispecific DART product candidates. This progress includes: a first patient has been dosed with MGD013, a DART molecule that recognizes PD-1 and LAG-3; and the submission of an Investigational New Drug (IND) application with the FDA for MGD014, a DART molecule that targets HIV-infected cells and CD3. MacroGenics retains worldwide rights to both of these product candidates.

MGD013 recognizes both PD-1 and LAG-3 and was designed to enable the co-blockade of these two immune checkpoint molecules co-expressed on T cells. MGD013 has a prolonged serum half-life and is being developed for the potential treatment of a wide range of cancers, including both solid tumors and hematological malignancies. MGD013 is MacroGenics’ first in a series of product candidates that recognize multiple immune regulator targets as a single recombinant molecule.

MGD014 is a bispecific, Fc-bearing DART molecule that targets HIV-infected cells and CD3-expressing T cells, and is being developed by MacroGenics under a contract awarded in September 2015 by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.  NIAID recently notified MacroGenics that it was exercising the first of two options under the HIV contract, funding MacroGenics’ advancement of MGD014 into Phase 1 clinical trials as well as the development and testing of a second DART molecule. Under the exercised option, funding of up to $10.8 million is available to MacroGenics for these development efforts. The second option, if later exercised by NIAID, would provide up to an additional $6.3 million for continued development efforts on one or both molecules. Assuming MGD014 IND clearance by the FDA, the Company believes this molecule will be the first clinical bispecific molecule targeting an infectious agent.

“MacroGenics continues to progress its clinical pipeline, and with the recent advancement of MGD013 and MGD014, there are multiple DART molecules being tested in the clinic across multiple modalities and therapeutic areas,” said Scott Koenig, M.D., Ph.D., President and Chief Executive Officer of MacroGenics.

Background on Bispecific DART Platform

MacroGenics' DART platform enables the targeting of multiple antigens or cells by using a single molecule with an antibody-like structure. The Company has created over 100 DART molecules which have been configured for the potential treatment of cancer, autoimmune disorders and infectious disease. These DART molecules can be tailored for either short or prolonged pharmacokinetics and have demonstrated good stability and attractive manufacturability.

About MacroGenics, Inc.

MacroGenics is a clinical-stage biopharmaceutical company focused on discovering and developing innovative monoclonal antibody-based therapeutics for the treatment of cancer, as well as autoimmune disorders and infectious diseases. The Company generates its pipeline of product candidates primarily from its proprietary suite of next-generation antibody-based technology platforms. The combination of MacroGenics' technology platforms and protein engineering expertise has allowed the Company to generate promising product candidates and enter into several strategic collaborations with global pharmaceutical and biotechnology companies. For more information, please see the Company's website at www.macrogenics.com. MacroGenics, the MacroGenics logo and DART are trademarks or registered trademarks of MacroGenics, Inc.

The development of MGD014 is funded in part by NIAID under contract no. HHSN272201500032C.

Cautionary Note on Forward-Looking Statements

Any statements in this press release about future expectations, plans and prospects for the Company, including statements about the Company's strategy, future operations, clinical development of the Company's therapeutic candidates, milestone or opt-in payments from the Company's collaborators, the Company's anticipated milestones and future expectations and plans and prospects for the Company and other statements containing the words "subject to", "believe", "anticipate", "plan", "expect", "intend", "estimate", "project", "may", "will", "should", "would", "could", "can", the negatives thereof, variations thereon and similar expressions, or by discussions of strategy constitute forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including: the uncertainties inherent in the initiation and enrollment of future clinical trials, expectations of expanding ongoing clinical trials, availability and timing of data from ongoing clinical trials, expectations for regulatory approvals, other matters that could affect the availability or commercial potential of the Company's product candidates and other risks described in the Company's filings with the Securities and Exchange Commission. In addition, the forward-looking statements included in this press release represent the Company's views only as of the date hereof. The Company anticipates that subsequent events and developments will cause the Company's views to change. However, while the Company may elect to update these forward-looking statements at some point in the future, the Company specifically disclaims any obligation to do so, except as may be required by law. These forward-looking statements should not be relied upon as representing the Company's views as of any date subsequent to the date hereof.

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Jim Karrels, Senior Vice President, CFO
MacroGenics, Inc.
1-301-251-5172, [email protected]

Karen Sharma, Senior Vice President
MacDougall Biomedical Communications
1-781-235-3060, [email protected]