FDA Committee Favors Approval of Opioid Addiction Implant
Probuphine works like a contraceptive implant, with 4 small implanted rods that provide a steady amount of medication for up to 6 months. Photo: Braeburn Pharmaceuticals.
The Psychopharmacologic Drugs Advisory Committee has recommended that the Food and Drug Administration approve an implant for treating opioid addiction.
The committee voted 12 to 5 in favor of approving probuphine, the first long-acting, subdermal buprenorphine implant to treat addiction to opioids. Buprenorphine is currently only available either as a dissolvable film that is placed under the tongue, or a pill, which allows some addicts to sell their supplies to get money for drugs.
Because probuphine works like a contraceptive implant, with four small implanted rods that provide a steady amount of medication for up to six months, its manufacturer Braeburn Pharmaceuticals says the implant eliminates that risk.
"I think this will save some folks' lives," said advisory committee member David Pickar, MD, an adjunct professor of psychiatry at Johns Hopkins Medical School in Baltimore.
The implant is also designed to simplify receiving and prescribing treatment for opioid addiction. Methadone is only available at specialized clinics where patients must typically go every day to get a dose. Buprenorphine is considered safer because it is less likely to cause an overdose, but physicians must be certified to dispense the drug and can only treat 100 patients at a time.
Doctors who want to prescribe probuphine must either refer patients to providers who are trained to implant medical devices, or would have to receive training to learn how to safely implant and remove it, according to Behshad Sheldon, president and CEO of Braeburn Pharmaceuticals. Probuphine takes about 10 to 15 minutes to implant and about 20 minutes to remove.
Some committee members had concerns about the clinical trial testing probuphine. Tracy Rupp, PharmD, MPH, RD, director of public health policy initiatives at the National Center for Health Research, a nonpartisan group that analyzes health data, urged the committee to reject probuphine, noting that its manufacturer presented only 1 clinical study showing the drug was effective.
For the study, probuphine implants were compared with buprenorphine film on “stable” patients, those who had already been taking 8 mg or less of the dissolvable buprenorphine film per day. After 6 months, 85% of those on probuphine tested negative for illegal drugs, compared with 72% of those taking the buprenorphine film.
Rupp noted that the study had multiple flaws: some missing urine samples were counted as negative. However, people addicted to opioids “often skip tests to avoid a positive test,” which could skew results.
The committee's acting chairwoman Judith Kramer also voted against recommending probuphine's approval because doctors don't yet know if it's effective for more than 6 months, and many people who are addicted to opioids need to take medications for years.
Rupp also had concerns that doctors don't yet know how to safely transition patients from buprenorphine films to the implant, which might put patients at risk for a relapse during the transition. "This is an unacceptable risk for stable patients," Rupp said.
The study also didn't match the demographics of addicts across the United States: 84% of patients in the study were white.
"This is not the real world of opioid addiction," Rupp said. "Many of these patients will require treatment for years. We need long-term safety data from diverse populations. Patients will require a new incision every 6 months, creating an ongoing risk of harm due to bleeding and infectious complications."
1. Titan Pharmaceuticals and Braeburn Pharmaceuticals Announce FDA Advisory Committee Recommends Approval of Probuphine, First 6-Month Implant to Treat Opioid Addiction. PRNewswire. prn.to/1W8ezx7. Accessed January 13, 2016.
2. Panel recommends FDA approve implant to treat opiate addiction. USAToday. usat.ly/1Q3m48h. Accessed January 13, 2016.