FDA rejects Amphastar's filing for intranasal naloxone as opioid overdose treatment

Amphastar Pharmaceuticals announced Tuesday that the FDA issued a complete response letter regarding the company's filing seeking approval of intranasal naloxone for the emergency treatment of known or suspected opioid overdose.

According to Amphastar, the agency identified issues including user human factors study, device evaluation and other items that need to be addressed before the drug can be cleared. CEO Jack Zhang said "while we are disappointed to have not received approval at this time, we intend to continue to work with the FDA to address their concerns."

Amphastar indicated that it will continue to offer naloxone in pre-filled syringes while it seeks approval of the nasal spray version.