MacroGenics’ (NASDAQ:MGNX) Phase 3 trial of margetuximab met its first sequential primary endpoint of progression-free survival (PFS) in patients with HER2-positive metastatic breast cancer.
The median PFS of patients treated with margetuximab and chemotherapy was 5.8 months, compared with 4.9 months in patients treated with trastuzumab and chemotherapy, the standard of care.
Overall survival (OS) data is currently based on 158 events and is immature, with a median OS prolonged by 1.7 months in margetuximab-treated patients. The company plans to conduct additional pre-specified interim OS analyses based on 270 and 385 events in the second half of 2019 and in 2020, respectively.
“For overall survival, we anticipate the preliminary positive trend in favor of margetuximab to continue, although subsequent results could fluctuate as additional events accrue,” Dr. Scott Koenig, MacroGenics’ president and CEO, said in a statement.
MacroGenics plans to submit a biologics license application for margetuximab to the FDA in the second half of 2019.
