The critical tone of FDA briefing documents examining Amgen Inc.'s cancer immunotherapy drug, talimogene laherparepvec, or T-vec, in advance of Wednesday's joint meeting of the Cellular, Tissue and Gene Therapies and Oncologic Drugs Advisory Committee (adcom) wasn't especially surprising, given that T-vec showed a "strong trend" but missed statistical significance in overall survival (OS) in a phase III study in metastatic melanoma.