NCT05262270

Extended-Release Naltrexone and Monthly Extended-Release Buprenorphine for Cocaine Use Disorder (CURB-2)

Randomized, Placebo-Controlled Trial of Extended-Release Naltrexone and Monthly Extended-Release Buprenorphine for Cocaine Use Disorder (CURB-2)

• Status: Completed
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 427 (actual)
• Sponsor: University of Texas Southwestern Medical Center · Academic / Other
• Sex: All
• Age: 18 Years – 65 Years
• Healthy volunteers: Not accepted

Summary

This is an 8-week, double-blind, randomized placebo-controlled trial of the efficacy of a combination of extended-release naltrexone (XR-NTX) and extended-release buprenorphine (XR-BUP) compared to matched placebo injections (PBO-Inj) for the treatment of cocaine use disorder (CUD).

Detailed description

The primary objective of this study is to assess the efficacy of XR-NTX plus XR-BUP as a combination pharmacotherapy for CUD. Approximately four hundred and twenty-six adults will be randomized into the study at 8-12 sites in the U.S. Eligibility will be determined during a maximum 21-day screening period. After screening/baseline is completed and eligibility is confirmed, participants will be randomized and begin the 1-week medication induction phase followed by the 8-week medication phase of the trial. Participants will be randomized in a 1:1 ratio to either 1) XR-NTX + XR-BUP arm and receive injections of extended-release naltrexone (XR-NTX; as Vivitrol®) and extended-release buprenorphine (XR-BUP; as SublocadeTM), or to 2) PBO-Inj matching the timeline and delivery methods of injections for the XR-NTX + XR-BUP arm. XR-NTX or PBO-Inj injections will be provided on the day of randomization and in Weeks 3 and 6. XR-BUP or PBO-Inj injections will be provided on days 3-5 following randomization and in week 4. During the 1-week induction phase and the 8-week medication phase, participants will be asked to attend clinic twice weekly for collection of urine samples and to complete assessments as indicated on the schedule of assessments. Following the 8-week medication phase, participants will be asked to attend clinic weekly for the follow-up phase during Weeks 9-12. Participants will be involved in the study for approximately 16 weeks, including a screening/baseline period of up to 3 weeks (i.e., 21 days), 1 week for randomization and medication induction, 8 weeks of medication, and 4 weeks of follow-up. The screening phase may differ by participant in the length of time needed to complete preliminary eligibility assessments. Randomization and medication induction visit may take approximately 2 hours. Twice-weekly visits during the medication phase will range from about 20 to 90 minutes in length depending on scheduled assessments. Medication administration visits may require an additional 2 hours. Visits in the follow-up phase will take place approximately 30-60 minutes to complete. An 8-week medication period was selected based on expected time for group differences to emerge and for pragmatic issues related to medication dosing. Enrollment is expected to take place over a period of approximately 13 months, with an approximate total of 16 months of study visits.

Conditions

• Cocaine Use Disorder

Interventions

Type	Name	Description
DRUG	Extended-Release Naltrexone	XR-NTX (Extended-Release Naltrexone) doses of 380mg (Weeks 0, 3 and 6) via intramuscular (IM) injections in the gluteus.
DRUG	Extended Release Buprenorphine	Extended-Release buprenorphine (XR-BUP) two doses of 300mg XR-BUP (Weeks 0, 4) via subcutaneous injections in the abdomen. Option for 100mg at Weeks 3 and 6 (if needed to alleviate side effects).
DRUG	Placebo (PLB) Injectable matched to XR-NTX	3 doses of intramuscular injections (Week 0, 3, 6)
DRUG	Placebo (PLB) Injectable matched to XR-BUP	2 doses of subcutaneous injections (Week 0, 4)

Timeline

• Start date: 2023-04-18
• Primary completion: 2025-06-27
• Completion: 2025-07-21
• First posted: 2022-03-02
• Last updated: 2025-10-21

Locations

12 sites across 1 country: United States

Regulatory

• FDA-regulated drug study