Trevi Therapeutics, Inc. announced the 52-week results from its phase 2b/3 PRISM open-label extension (OLE) study of Haduvio for the treatment of prurigo nodularis. The data was presented by Professor Elke Weisshaar on October 13th at the European Academy of Dermatology & Venereology (EADV) Congress 2023 in Berlin, Germany. The slides from the presentation will be available for 30 days on the Company's website.

The phase 2b/3 PRISM (Pruritus Relief through Itch-Scratch Modulation) trial was a randomized, double-blind, placebo-controlled study to evaluate the efficacy and safety of nalbuphine ER in prurigo nodularis. Following the completion of the initial 14-week portion of the trial, subjects were eligible to roll into an additional 38-week open label extension period during which all participants received Haduvio 162mg twice a day (BID). Post hoc analyses demonstrated continued reduction in mean WI-NRS for those participants who remained on Haduvio through 52 weeks.

Adverse Events Reported During 38-Week Open-Label Period: 151 subjects completed the open-label extension, adding to the safety database for Haduvio. The safety data were generally consistent with the safety profile of Haduvio observed in the 14-week portion of PRISM and previous trials of Haduvio. Adverse events reported with a frequency greater than 5% in the 38-week open-label period included nausea, dizziness, vomiting, fatigue, and somnolence.

Study discontinuation due to adverse events occurred in 13% of subjects during the open-label period, and serious adverse events were reported for 13 subjects, although only 2 of these events were considered potentially treatment related. About PRISM: The Phase 2b/3 Pruritus Relief through Itch Scratch-Modulation (PRISM) trial was a randomized, double-blind, placebo-controlled study to evaluate the efficacy and safety of Haduvio in prurigo nodularis. In the trial, participants were randomized equally across two treatment groups (oral Haduvio 162 mg or placebo twice daily including an initial 2-week blinded titration period).

The primary endpoint of the trial was the proportion of participants achieving a greater than or equal to 4-point improvement in the weekly mean Worst Itch Numerical Rating Scale (WI-NRS) score at week 14 compared to baseline. Participants that completed week 14 were eligible to roll into an additional 38-week open label extension trial.