Braeburn Pharmaceuticals received the go-ahead from the FDA to initiate a new clinical trial of implants for the continuous subdermal delivery of buprenorphine to combat opioid dependence.
The double-blind, double-dummy study will enroll 180 patients and consist of two treatment arms. One group will continue to receive standard buprenorphine therapy delivered sublingually, while the treatment group will receive four investigational subdermal Probuphine implants.
The FDA previously rejected the implant's New Drug Application, citing the need for additional data about higher doses of the medication and the implant's insertion and removal. Probuphine obtained the FDA's priority review designation in January 2013 and was the subject of 6 clinical trials prior to FDA rejection, according to clinicaltrials.gov.
The April 30 agreement with the FDA amounts to an extra life. "The responsiveness and insightful guidance from the FDA has been very helpful in establishing the path forward for the Probuphine program," said Braeburn CEO Behshad Sheldon in a statement. "We have revised the final study protocol to incorporate the FDA's guidance, and preparations are under way to qualify investigator sites, obtain Institutional Review Board (IRB) approval and train the clinicians in study procedures."
Enrollment is anticipated to begin in midyear and study completion is scheduled to occur by mid-2015.
Braeburn was granted North American commercial rights to the product by Titan Pharmaceuticals ($TTNP), the developer of the delivery technology. "The continuous drug delivery system consists of a small, solid rod made from a mixture of ethylene-vinyl acetate and a drug substance," Titan explains on its website. It is typically placed subdermally in the upper arm and delivers buprenorphine for 6 months.
Advantages of the delivery method include constant, linear dosing and improved patient compliance and retention, the companies say. In addition, buprenorphine pills can be abused by snorting or injecting crushed tablets, similar to other painkillers.
"We appreciate the collaborative process that has resulted in this robust study design and we are encouraged by the interactions with potential investigators regarding clinical study conduct. We will continue to support our partner, Braeburn, with the study and remain optimistic about the resubmission of the Probuphine NDA next year," said Titan Executive Vice President Kate Glassman-Beebe in a statement.
The companies say there are 2.7 million people addicted to opioids in the U.S., 80% of whom are on prescription drugs. More than 1 million people in the U.S. sought treatment for the addiction in 2011, they say. The trial approval occurs as the issue of prescription drug abuse moves into the spotlight due to the now-overturned ban of the painkiller Zohydro ER in Massachusetts over concerns that it is easily abused.
- read the Braeburn release
- and the Titan release