FDA issues Complete Response Letter to Invidior for its naloxone nasal spray to treat opioid overdose.

Indivior Inc., a subsidiary of Indivior PLC announced that it has received a Complete Response Letter from the FDA regarding its New Drug Application for naloxone nasal spray, an intranasal naloxone product candidate for the emergency treatment of known or suspected opioid overdose.

The FDA’s response was principally focused on clinical pharmacology that found the early stage uptake of naloxone nasal spray did not fully meet the FDA’s threshold as determined by the reference product (0.4 mg naloxone by intramuscular injection). Indivior is evaluating the FDA’s comments to determine its next steps to address FDA’s findings.

Comment: This delay at the FDA is an embarrassment for Invidior as its competitor, Adapt Pharma with Lightlake Therapeutics, recently secured FDA approval for Narcan, also a nasal naloxone product.