MGNX - Why MacroGenics Is Tanking Today
Shares of MacroGenics (NASDAQ: MGNX), a small-cap clinical-stage biopharma focused on cancer, dropped 15% as of 3:13 p.m. EDT on Wednesday. The double-digit swoon is traceable to a clinical update that was shared with investors.
MacroGenics announced top-line results from its second pre-specified interim overall survival (OS) analysis for its Phase 3 SOPHIA study. This trial is testing its lead compound margetuximab as a treatment for patients with HER2-positive metastatic breast cancer who have already failed on other therapies.
The OS analysis was based on 270 events. In the intent-to-treat (ITT) population, the median OS of patients treated with MacroGenics' margetuximab and chemotherapy was 21.6 months, which compares favorably to 19.8 months that was observed in the group of patients who received Roche's blockbuster drug Herceptin (trastuzumab) and chemotherapy. However, the p-value for this data was 0.326, which is well above the 0.05 that statisticians like to see.