The U.S. FDA issued a complete response letter to Shin Nippon Biomedical Laboratories Ltd.’s U.S. subsidiary, Satsuma Pharmaceuticals Inc., for its NDA for dihydroergotamine nasal powder (STS-101) for acute treatment of migraine, with or without aura, in adults. Shin Nippon acquired Satsuma for $220 million in April 2023 and gained rights to STS-101.