The Food and Drug Administration has recently raised questions and regulatory hurdles for several drugs. The FDA questioned the efficacy of Otsuka's Rexulti combination for PTSD, requesting more data ahead of advisory committee meetings. GSK faces FDA scrutiny over the safety and efficacy of its antibody-drug conjugate Blenrep in multiple myeloma, citing high ocular toxicity incidences and uncertain dosing. Ultragenyx's gene therapy for Sanfilippo syndrome received a complete response letter due to manufacturing concerns. The FDA has also demanded black box warnings on Sarepta's Elevidys gene therapy for Duchenne muscular dystrophy. These regulatory challenges underscore ongoing scrutiny of novel therapies, impacting development timelines and market access.