Povorcitinib for nonsegmental vitiligo: two randomized, controlled, phase 3 STOP-V trials

There is an unmet need for repigmentation therapies for patients with nonsegmental vitiligo (NSV) who are candidates for systemic therapy. Here, 52-week primary results are reported from two parallel phase 3, randomized, double-blind, placebo-controlled trials of once-daily povorcitinib (oral, highly selective JAK1 inhibitor) 30 mg in adults with moderate-to-severe NSV (STOP-V1 and STOP-V2). STOP-V1 and STOP-V2 enrolled 467 and 449 patients, respectively. In both studies, the primary endpoint of ≥75% improvement in the facial Vitiligo Area Scoring Index (F-VASI75) at week 52 was met, demonstrating statistically significant and clinically meaningful repigmentation with povorcitinib versus placebo (STOP-V1: 18.9% versus 6.8%; odds ratio, 3.1; 95% confidence interval 1.6-5.9; P = 0.0003; STOP-V2: 18.9% versus 3.1%; odds ratio, 7.5; 95% confidence interval 3.0-18.6; P < 0.0001). Povorcitinib was well tolerated; the percentage of patients with any treatment-emergent adverse event (TEAE) was similar between the povorcitinib and placebo groups in both studies (STOP-V1/STOP-V2, 68.7%/66.7% versus 63.7%/62.7%). The most common TEAEs with povorcitinib were nasopharyngitis (STOP-V1/STOP-V2, 11.2%/11.3% versus placebo, 9.8%/11.1%), acne (10.7%/10.8% versus 3.0%/2.2%) and upper respiratory tract infection (6.9%/14.0% versus 9.0%/10.7%). Serious TEAEs were generally single events, and Janus kinase inhibitor class-specific TEAEs were absent or rare. These results support once-daily povorcitinib as an effective and well-tolerated systemic treatment for adults with moderate-to-severe NSV. ClinicalTrials.gov identifiers: NCT06113445 , NCT06113471 .