The Food and Drug Administration (FDA) has accepted for review the resubmitted New Drug Application (NDA) for Brixadi™ (buprenorphine) extended-release weekly and monthly subcutaneous injection for the treatment of moderate to severe opioid use disorder in patients who have initiated treatment with a single dose of a transmucosal buprenorphine product or who are already being treated with buprenorphine.

The resubmitted NDA was in response to a Complete Response Letter (CRL) issued by the FDA in December 2020. In the CRL, the FDA stated that the NDA could not be approved in its present form due to “deficiencies found during a recent inspection at a third-party manufacturing facility in the US.” No other deficiencies were noted in the application, which included data from a phase 3 trial ( Identifier: NCT02651584) that compared the long-acting subcutaneous treatment to an existing standard of care, sublingual buprenorphine/naloxone.

Study results showed that Brixadi met the primary endpoint of noninferiority for responder rate (defined as a patient with at least 33% of urine toxicology results collected during weekly visits and 67% of urine toxicology results collected during monthly visits being negative for illicit opioids and self-reported illicit opioid use) vs daily sublingual buprenorphine/naloxone (P <.001). A key secondary endpoint, superiority to sublingual buprenorphine/naloxone in the percentage of negative opioid assessments from week 4 to 24, was also met (P =.004). Apart from mild to moderate injection site reactions, the safety profile of Brixadi was found to be similar to the known profile of oral buprenorphine.

If approved, Brixadi would be supplied as weekly (8mg, 16mg, 24mg, 32mg) and monthly (64mg, 96mg, 128mg) injections and would be used as part of a complete treatment plan to include counseling and psychosocial support. A Risk Evaluation and Mitigation Strategy (REMS) program would also be established; treatment would be administered only by a healthcare provider in a healthcare setting.


  1. FDA accepts Braeburn’s New Drug Application resubmission for Brixadi™ (buprenorphine) extended-release subcutaneous injection for moderate to severe opioid use disorder. [press release]. Plymouth Meeting, PA: Braeburn; June 26, 2021. 
  2. Braeburn announces publication of positive phase 3 results for long-acting buprenorphine for treatment of opioid use disorder in JAMA Internal Medicine. [press release]. Plymouth Meeting, PA: Braeburn; May 14, 2018.