Titan Pharmaceuticals Inc. is discontinuing sales of its Probuphine implant for opioid use disorder in the U.S. as part of its restructuring plan.

Probuphine, or buprenorphine, is an implant placed underneath the skin marketed as a maintenance treatment for opioid addiction in clinically stable patients. The therapy is known as Sixmo in the EU.

South San Francisco, Calif.-based Titan said in an Oct. 15 news release that the reasons for the discontinuation include onerous commercialization requirements, financial constraints and suboptimal reimbursement rates. The COVID-19 pandemic has made the changing business environment complex and in turn exacerbated these issues, the pharmaceutical company added.

The company said sales of Probuphine may continue in the foreseeable future, but in an extremely limited way.

Titan will instead redirect its focus on other product development programs utilizing its ProNeura drug delivery technology, particularly the JT-09 ProNeura implants to be developed under a collaboration with JT Pharmaceuticals Inc., and the nalmefene implant program, which is funded by the National Institute for Drug Addiction.

Also part of the company's restructuring are certain management changes, with President and CEO Sunil Bhonsle retiring and Executive Chairman Marc Rubin becoming chairman and CEO. Chief Scientific Officer Kate Beebe DeVarney will serve as president and COO.

Titan said it expects to significantly reduce operating costs after winding down its commercial operations. The company is also in talks to eliminate outstanding debt.