BXCL501 240 µg BID Cuts Opioid Withdrawal Scores by >30%, Lowers CV Events
In an 80-patient Phase 2 trial, BXCL501 240 µg BID reduced opioid withdrawal SOWS-Gossop scores by over 30% versus placebo by day 4. The 180 µg BID arm showed 18% orthostatic hypotension versus 50% with lofexidine (p<0.05) and reported no sedation versus 5% on lofexidine.
1. Trial Design and Patient Population
The investigator-sponsored Phase 2 NIDA-funded trial enrolled 80 adults with opioid use disorder undergoing a seven-day methadone taper, randomizing them to BXCL501 180 µg BID, BXCL501 240 µg BID, placebo, or lofexidine 0.54 mg QID.
2. Efficacy Results
The BXCL501 240 µg BID arm achieved a greater than 30% reduction in SOWS-Gossop scores compared to placebo, with peak symptom relief by days 3 and 4, and numerically exceeded the reductions seen with lofexidine.
3. Safety and Tolerability
Both BXCL501 doses exhibited similar or lower cardiovascular adverse events than lofexidine, with orthostatic hypotension at 18% for the 180 µg BID group versus 50% for lofexidine (p<0.05), and no sedation or somnolence reported in the BXCL501 arms versus 5% with lofexidine.
4. Implications and Next Steps
These positive topline findings support further development of BXCL501 for opioid withdrawal management, potentially offering a more tolerable twice-daily oral formulation, with plans for subsequent trials to confirm efficacy and safety in broader populations.