Title: Effect of Buprenorphine Weekly Depot (CAM2038) and Hydromorphone Blockade in Individuals With Opioid Use Disorder

Walsh, SL et al.


What You Need to Know:

In patients with opioid use disorder (OUD), 24 and 32mg doses of CAM2038, a weekly, subcutaneous depot formulation of buprenorphine, was found to not only produce immediate and sustained blockade of opioid effects, but suppress withdrawal as well.

Trial Design:

  • 47 patients with DSM-V moderate-severe OUD were included in this double-blind, randomized within-patient clinical trial to evaluate the efficacy of CAM2038 on the blockade of opioid effects and suppression of withdrawal
  • “A total of five 3-day test sessions evaluated the response to hydromorphone (0, 6, and 18 mg intramuscular in random order; 1 dose/session/day). After the first 3-day session (ie, qualification phase), participants were randomized to either CAM2038 weekly at 24 mg (n=22) or 32 mg(n=25); the assigned CAM2038 dose was given twice, 1 week apart (day 0 and 7). Four sets of sessions were conducted after randomization (days 1-2, 4-6, 8-10, and 11-13)”
  • Primary endpoint: maximum rating for drug liking according to the visual analog scale
  • Secondary endpoints: other visual analog scales, scales assessing opioid withdrawal, outcomes regarding physiological and pharmacokinetic conditions

Key Outcomes:

  • Immediate and sustained blockade of hydromorphone effects were observed for both CAM2038 doses (liking maximum effect: effect size of 0.813 for 24mg group [P<0.001] and 0.753 for 32mg group [P<0.001])
  • Suppression of withdrawal was also observed for both doses of CAM2038 (Clinical Opiate Withdrawal Scale: effect size of 0.617 for 24mg group [P<0.001] and 0.751 for 32mg group [P<0.001])
  • Pharmacokinetic data: maximum concentration of buprenorphine seen around 24 hours; “apparent half-life of 4 to 5 days and approximately 50% accumulation of trough concentration from first to second dose”