The Nalmefene implant is in development as a six-month or longer (subdermal) formulation of this opioid antagonist for the prevention of relapse following opioid detoxification in adults with Opioid Use Disorder (OUD).

In September 2019, the National Institute for Drug Addiction (“NIDA”) awarded approximately $8.7 million in a two-year grant for its nalmefene implant development program for the prevention of opioid relapse following detoxification from opioids. This grant provides funds for the completion of implant formulation development, cGMP manufacturing and non-clinical studies required for filing an Investigation New Drug (“IND”) application.

During the first quarter of 2020, the Company met with the U.S. Food and Drug Administration (“FDA”) to review non-clinical development plans and obtain guidance regarding filing an IND.

 ReacX Pharmaceuticals (formerly known as Fedson, Inc.) then acquired the Nalmefene asset in July 2023.

On February 2025, NIDA announced it has been awarded three-year, $10.35 million grant (the “Grant”) from NIDA. The Grant is awarded under the National Institutes of Health (“NIH”) HEAL Initiative (“The Helping to End Addiction Long-term Initiative”) and is to support the clinical development of a six-month nalmefene implant using ReacX’s proprietary ProNeura™ drug delivery system, which enables long-term, continuous medication release. The implant is being developed to prevent opioid addiction relapse after detoxification.

The IND has been filed with the FDA and ReacX is preparing to start the Phase 1 clinical trial by 4Q 2025.