Buprenorphine is a widely used therapy for opioid use disorder (OUD), but the daily sublingual formulations currently available do have their own issues. These include adherence difficulties as well as the risk of misuse or diversion.
A clinical study published in JAMA Psychiatry has now tested a new, weekly injectable form of buprenorphine called CAM2308. “CAM2038 produced clinically relevant buprenorphine plasma levels, translating into rapid and sustained opioid blockade and withdrawal suppression, and was well-tolerated both systemically and locally. Findings suggest that CAM2038 formulations will be effective in reducing illicit opioid use and relapse, while eliminating the risk for misuse and diversion,” wrote Sharon Walsh, Ph.D., of the Center on Drug and Alcohol Research at the University of Kentucky and colleagues.
For this study, supported in part by CAM2038 manufacturer Braeburn Pharmaceuticals, 47 adults with moderate-to-severe OUD were randomized to received two doses of either 24 mg or 32 mg of CAM2038 one week apart. Immediately prior to and four times during the two-week trial, the participants were also randomized to receive a placebo or 6 mg or 18 mg of the opioid hydromorphone for three consecutive days in order to illicit “drug liking” responses and evaluate CAM2038 response.
Walsh and colleagues observed that both weekly CAM2038 doses produced rapid and sustained inhibition of hydromorphone’s euphoria-inducing effects, even at the 18-mg hydromorphone dose. CAM2038 was also able to effectively suppress opiate withdrawal symptoms throughout the two-week study period.
Adverse events due to CAM2038 were reported by a little more than half of the participants and mostly rated as mild. Constipation, injection-site pain, and headache were the most common effects reported.
This study was also supported by the National Institute on Drug Abuse National Center for Research Resources and the National Center for Advancing of Translational Sciences.
To read more about this topic, see the Psychiatric News article “Tackling Opioid Overdose Epidemic Demands Multiple Approaches.”
Live Mentally Healthy,
Dr. Jennie Byrne