US FDA rejects Titan Pharma's Probuphine NDA

California, USA-based Titan Pharmaceuticals (OTCBB: TTNP) has received a Complete Response Letter from the US Food and Drug Administration relating to its New Drug Application for Probuphine (buprenorphine), the company's investigational subdermal implant for the maintenance treatment of opioid dependence in adult patients, despite an overall favorable review by an FDA advisory panel (The Pharma Letter March 22). The stock plunged 72% to $0.45 a share in early trading on Wednesday.

"Titan and our partner, Braeburn Pharmaceuticals, are extremely surprised and disappointed with the FDA's response. Probuphine is a diversion-resistant formulation that is consistent with the recently-issued FDA guidance supporting diversion- and abuse-resistant products, and the NDA was designated Priority Review by the FDA. We believe Probuphine has demonstrated both safety and efficacy in accordance with primary endpoints that were pre-agreed with the FDA and, moreover, the safety, efficacy and overall approval of Probuphine was strongly supported by the Psychopharmacologic Drugs Advisory Committee," said Marc Rubin, executive chairman of Titan Pharmaceuticals.

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