Press Release

ROCKVILLE, MD, April 03, 2019 (GLOBE NEWSWIRE) --

MacroGenics, Inc. (NASDAQ: MGNX), a clinical-stage biopharmaceutical company focused on discovering and developing innovative monoclonal antibody-based therapeutics for the treatment of cancer, today announced the presentation of preclinical and clinical data at the American Association for Cancer Research Annual Meeting 2019 (AACR) held in Atlanta, Georgia.

AACR Poster Presentations

The posters presented at AACR by MacroGenics and its collaborators are listed below and available for download from the Events & Presentations page in the Investors section of MacroGenics' website at http://ir.macrogenics.com/events.cfm.

Margetuximab

Margetuximab is a novel, investigational anti-HER2 monoclonal antibody (mAb) with an Fc domain engineered to increase the molecule’s ability to engage certain Fc-gamma receptors of cells of the innate immune system to enhance killing of tumor cells. SOPHIA, a Phase 3 clinical trial of margetuximab in HER2-positive metastatic breast cancer patients, met the primary endpoint of prolongation of progression-free survival (PFS) in patients treated with the combination of margetuximab plus chemotherapy compared to trastuzumab plus chemotherapy.

Preclinical data presented at AACR showed that margetuximab, while retaining the same Fc-independent tumor growth-inhibition activity as trastuzumab, exhibited more potent antibody-dependent cell-mediated cytotoxicity (ADCC) and induced greater activation and proliferation of NK cells in vitro compared to trastuzumab. In addition, the combination of margetuximab and pertuzumab mediated ADCC in vitro with greater potency than the combination of trastuzumab and pertuzumab. 

• Abstract #1538: Margetuximab Mediates Greater Fc-dependent Anti-tumor Activities than Trastuzumab or Pertuzumab In Vitro

“In margetuximab, we have designed an Fc-enhanced antibody that has been shown in a Phase 3 trial to have a superior PFS outcome to that of trastuzumab, an analog antibody with a wild-type Fc domain,” said Scott Koenig, M.D., Ph.D., President and CEO of MacroGenics. “The in vitro data presented at AACR comparing margetuximab to trastuzumab help to further validate our Fc Optimization technology and the SOPHIA results from a mechanistic perspective.”

MGA012 (INCMGA0012)

MGA012 (INCMGA0012) is an investigational anti-PD-1 mAb exclusively licensed to Incyte Corporation (Incyte) on a worldwide basis in 2017. MacroGenics retains the right to develop its pipeline of product candidates in combination with MGA012. Incyte is pursuing development of MGA012 monotherapy through three registration-directed studies in MSI-high endometrial cancer, Merkel cell carcinoma and anal cancer. In addition, MacroGenics and Incyte are each studying MGA012 in combination with other agents.

Data presented at AACR by Incyte included pharmacodynamic and pharmacokinetic analyses of blood samples from patients with advanced solid tumors in a Phase 1 study of MGA012 (NCT03059823). Data from the following two posters presented by Incyte suggest that MGA012 is biologically active and leads to an increase in circulating T cell activation and support the use of a flat dosing regimen in later phase clinical trials:

• Abstract #CT085: Pharmacodynamic Correlates in a Phase 1 Study of INCMGA00012, a PD-1 Antagonistic Monoclonal Antibody
• Abstract #LB-268: Assessment of Flat Dosing Strategy for INCMGA00012 in Patients with Advanced Tumors

IMGC936

IMGC936 is a novel, investigational antibody-drug conjugate (ADC) targeting ADAM9, a cell surface protein overexpressed in multiple solid tumor types. IMGC936 is being advanced under a co-development agreement with ImmunoGen, Inc (ImmunoGen). Preclinical data presented at AACR showed activity of IMGC936 in vitro and in xenograft models of human tumors expressing ADAM9:

• Abstract #1533: IMGC936, a First-in-Class ADAM9-targeting Antibody-Drug Conjugate, Demonstrates Promising Anti-tumor Activity

CD137-based TRIDENT™ Molecules

CD137 (4-1BB) signaling provides co-stimulation of CD8 or NK cells following antigen or FcγR engagement, respectively. However, efforts to leverage CD137 co-stimulation via agonistic mAbs have been thwarted by limited clinical efficacy or unacceptable toxicity. Bispecific targeting strategies linking CD137 activation to a tumor-targeting moiety provides an approach to localize CD137 activation to the tumor microenvironment. MacroGenics’ TRIDENT platform reflects the continuing evolution of the Company’s multi-specific antibody-based targeting expertise. Preclinical data presented at AACR demonstrate the potential for TRIDENT molecules with a 2:1 valency to maximize immune co-stimulatory activity through CD137 engagement that is dependent upon the presence of the target tumor antigen:

• Abstract #554: Tumor-antigen 5T4-dependent Activation of the CD137 Costimulatory Pathway by Bispecific 5T4 x CD137 TRIDENT™ molecules
• Abstract #1560: Selection of a Bispecific Trivalent HER2 x CD137 x CD137 TRIDENT™ Format Providing Optimal Tumor-anchored Immune Co-stimulation

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. The Company generates its pipeline of product candidates primarily from its proprietary suite of next-generation antibody-based technology platforms, which have applicability across broad therapeutic domains. 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, DART® and TRIDENT are trademarks or registered trademarks of MacroGenics, Inc.

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.

Contacts:

MacroGenics, Inc.Jim Karrels, Senior Vice President, CFO
Anna Krassowska, Ph.D., Vice President, Investor Relations & Corporate Communications
1-301-251-5172, info@macrogenics.comMacDougall Biomedical CommunicationsKaren Sharma, Senior Vice President
1-781-235-3060, ksharma@macbiocom.com

Source: MacroGenics, Inc.