BioCentury
ARTICLE | Clinical News

MM-121: Additional Phase II data

June 16, 2014 7:00 AM UTC

Additional data from a double-blind, placebo-controlled, international Phase II trial in 115 patients who have failed anti-estrogen therapy showed that IV MM-121 plus oral Aromasin exemestane led to a median PFS, the primary endpoint, of 3.7 months vs. 2.5 months for Aromasin alone (HR=0.77, 95% CI: 0.5, 1.2, p=0.25). In 17 patients who were positive for the biomarker heregulin and who also had low levels of HER2 expression, MM-121 plus Aromasin significantly improved median PFS vs. Aromasin alone (7.7 vs. 2.7 months, HR=0.31, 95% 0.1, 0.98, p=0.045). Patients received a loading dose of 40 mg/kg MM-121 followed by 20 mg/kg MM-121 once weekly plus Aromasin or Aromasin alone. Data were presented at the American Society of Clinical Oncology meeting in Chicago. Merrimack previously reported that MM-121 plus Aromasin missed the primary endpoint of improving PFS with an HR of <=0.5 vs. Aromasin alone, but reduced the risk of progression with an HR for PFS of 0.32 (95% CI: 0.1, 1) in 17 patients who were positive for a combination of 2 undisclosed biomarkers (see BioCentury, Dec. 9, 2013). Merrimack said it is considering further confirmatory studies with MM-121 in breast cancer. ...