SILVER SPRING, Maryland—The Oncologic Drugs Advisory Committee (ODAC) voted 12-to-2 not to recommend that FDA approve Junovan (mifamurtide, IDM Pharma) for treating newly diagnosed, resectable high-grade osteosarcomas in combination with chemotherapy following surgical resection.
Junovan is a liposomal formulation of muramyl tripeptide phosphatidylethanolamine (MPT-PE), which induces the infiltration of inflammatory macrophages into lung metastases. IDM Pharma presented data from a phase III NCI-sponsored cooperative group study of 678 nonmetastatic osteosarcoma patients with resectable disease (age range,1.4 to 30.6 years). The study, a factorial design, used two chemotherapy regimens—one standard and one experimental—each with or without Junovan.
The trial showed no statistical advantage for Junovan in disease-free survival, the primary endpoint, although the trend favored the drug. An analysis of overall survival, which was not prespecified in the protocol, showed a 77% 6-year survival probability for Junovan-treated patients vs 66% for those who did not receive the drug (P = .0183). "This robust survival benefit came without cost in safety," said Paul Meyers, MD, of Memorial Sloan-Kettering Cancer Center, who presented the trial data for IDM Pharma.
FDA reviewers said the single study did not provide substantial evidence of effectiveness: The primary endpoint did not reach significance, and the overall survival analysis was not part of the study plan. "Follow-up data have not been rigorously collected and are incomplete, with insufficient follow-up for a significant proportion of patients," said FDA statistical reviewer Laura Lu, PhD.