Advisers to the U.S. Food and Drug Administration recommended that Titan Pharmaceuticals Inc treatment for opioid addiction be approved, but were unconvinced that the company’s marketing plan was safe enough, given the potential for abuse of such drugs.
The panel of advisers, who met in Silver Spring, Maryland to evaluate the safety and efficacy of Titan’s Probuphine, also echoed concerns expressed on Tuesday by FDA staff, who said it was difficult to decide if the intended dose of the drug would be effective enough.
FDA advisers voted 10-4, with one abstention, to agree that Probuphine be approved, based on its safety, effectiveness and risk-benefit profile as seen in its clinical studies.
“I think it is a drug that we definitely need and the more we can put into our (opioid dependence) treatments, the better for our patients,” said Dr. Louis Baxter, one of the panel members said.
Federal data shows that drug overdose death rates have more than tripled since 1990. In 2008, more than 36,000 people died from an overdose, mostly caused by opioid painkillers, which outpaced deaths from heroin and cocaine combined.
Probuphine, a long-acting version of British drugmaker Reckitt-Benckiser Group Plc’s branded drugs Subutex and Suboxone, is implanted under the skin of the upper arm during a 10-15-minute office procedure for about six months.
“I think Probuphine’s safety is adequate, due in part to the fact that we have an adequate medication already on the market using implant materials we don’t doubt,” said another panel member Dr. Christopher Kratochvil, referring to the implantable, progestin-releasing contraceptive Norplant.
Probuphine needs to be surgically inserted under the skin, for which general physicians would need training. Some of the FDA advisers worried that Titan did not have an adequate plan in place for this.
“If you’re not a surgeon and don’t do implants on a regular basis, you’re likely to wind up with a deep insertion, which is a big problem,” one of the panel members said.
Five of the advisers voted “yes” when asked if the risk-mitigation strategy proposed by Titan sufficiently addressed the potential danger of abuse and misuse that could come with the drug’s use.
Four voted “no,” while 6 abstained, most saying they thought Titan needed to work better on how it would avoid misuse.
Dr. Edward Covington, the panel chairman, concluded the meeting saying that there was agreement Titan’s drug had a “great potential utility,” but deficiencies remained, in terms of finding the right dose and working out a risk-mitigation plan for when the drug goes to market.
The FDA is not required to, but usually takes its advisers’ vote into consideration when delivering a final verdict on marketing approval of a drug.
By Zeba Siddiqui