FDA AdComm Gives Opioid Dependence Implant Thumbs Up

January 19, 2016

Titan Pharmaceuticals last week won positive news from an FDA advisory committee, with panelists voting in favor of approving its implant to treat opioid addictions.

By a 12 to 5 vote, the Psychopharmacologic Drugs Advisory Committee decided that the medication’s potential to put a dent in the life-threatening epidemic — even by small and conservative amounts — was worth supporting a place in the market.

If approved, Titan’s six-month buprenorphine-containing subdermal implant Probuphine would be the first long-acting, non-oral drug of its kind to treat opioid addiction in dependent patients.

In March 2013, the same committee voted 10 to 4, with one abstention, to recommend approval of the implant. However, the FDA sent a complete response letter to the company that, among other issues, provided recommendations on product labeling and ways to improve Titan’s proposed risk evaluation and mitigation strategy for the candidate.

This time around, the company narrowed the implant’s indication and based its submission on a Phase 3 trial of 177 patients — many of whom were addicted to prescription painkillers. The FDA asked the committee to consider whether the company had adequately identified a patient population that could benefit from the product.

Although panel members expressed concerns about uncertainties in the data supporting its case, including missed follow-ups, they provided suggestions to encourage the treatment’s use in patients who saw the best responses.

The committee decided Probuphine showed noninferiority compared with other options. Further, its safety was well enough understood and could be monitored through REMS alongside surveillance studies and regular doctor visits while on the medication.

The news may come as a surprise for Titan. The company had received a tepid FDA response for the implant in briefing documents posted ahead of the meeting, with the agency saying the benefits of the formulation do not outweigh the risks.

The FDA acknowledged that the implant has advantages over other formulations, as it is difficult to abuse and is less likely to be accidentally ingested by children. However, there are concerns about implantation and removal, as surgeons must be trained on these procedures.

The company proposed a REMS that included a training and certification study for surgical implantation, and it conducted a study that showed effects in improving some procedural errors. It also proposed that restricted distribution and a training certification program.

Read the FDA briefing documents here: www.fdanews.com/01-11-16-fda-documents.pdf.