A phase 2b, randomized clinical trial of tapinarof cream for the treatment of plaque psoriasis: Secondary efficacy and patient-reported outcomes

Background: Tapinarof cream is a topical therapeutic aryl hydrocarbon receptor modulating agent under investigation for treatment of psoriasis and atopic dermatitis. Methods: In a phase 2b, double-blind, vehicle-controlled study, adults with plaque psoriasis were randomized to tapinarof cream 0.5% or 1% once or twice daily or vehicle once or twice daily for 12 weeks with 4-week follow-up. Efficacy outcomes included Physician Global Assessment (PGA) scores, change in PGA and total target lesion grading scores, and proportion of patients achieving 5 >= 50%, >= 75%, and >= 90% reductions in the Psoriasis Area and Severity Index scores from baseline (PASI50, PASI75, and PASI90). Results: At week 12, improvements were observed in all tapinarof groups vs vehicle in PGA response, change in PGA and total target lesion grading scores, PASI50 (71%-92% vs 10%-32%), PASI75 (46%-65% vs 5%-16%), and PASI90 (18%-40% vs 0%); all differences were statistically significant with tapinarof 1% once daily. Tapinarof responses were apparent from week 2, with significant efficacy at week 8 maintained through week 16. Most adverse events were mild or moderate. Limitations: The analyses reported require confirmation in larger prospective studies. Conclusions: Tapinarof may represent an important advance in the development of topical medicines for treatment of psoriasis.