Povorcitinib for hidradenitis suppurativa: the randomized, double-blind, placebo-controlled STOP-HS1 and STOP-HS2 phase 3 trials.
Although therapeutic options for hidradenitis suppurativa (HS) continue to expand, unmet needs remain substantial. We evaluated the efficacy and safety of povorcitinib (an oral, highly selective Janus kinase 1 (JAK1) inhibitor) in patients with moderate to severe HS in two randomized trials. STOP-HS1 and STOP-HS2 were identically designed, randomized, double-blind, placebo-controlled phase 3 trials. Adults with moderate to severe HS were randomized 2:2:1:1 to once-daily treatment through week 54
Although therapeutic options for hidradenitis suppurativa (HS) continue to expand, unmet needs remain substantial. We evaluated the efficacy and safety of povorcitinib (an oral, highly selective Janus kinase 1 (JAK1) inhibitor) in patients with moderate to severe HS in two randomized trials. STOP-HS1 and STOP-HS2 were identically designed, randomized, double-blind, placebo-controlled phase 3 trials. Adults with moderate to severe HS were randomized 2:2:1:1 to once-daily treatment through week 54: povorcitinib 45 mg; povorcitinib 75 mg; placebo with crossover at week 12 to povorcitinib 45 mg; or placebo with crossover at week 12 to povorcitinib 75 mg. The primary endpoint was HiSCR50 (≥50% decrease in total abscess and inflammatory nodule count, with no increase from baseline in abscess or draining tunnel count) at week 12. STOP-HS1/STOP-HS2 enrolled 608/619 patients, respectively. In both studies, both povorcitinib doses met the primary endpoint; in STOP-HS1, 82/204 (40%) patients in the povorcitinib 45-mg group and 82/202 (41%) in the 75-mg group versus 60/202 (30%) in the placebo group achieved HiSCR50 (OR (95% CI) 45 mg: 1.6 (1.1-2.5), P = 0.0240; 75 mg: 1.6 (1.1-2.4), P = 0.0214); corresponding values for STOP-HS2 were 88/208 (42%) and 88/208 (42%) versus 58/203 (29%; OR (95% CI) 45 mg: 1.8 (1.2-2.8), P = 0.0035; 75 mg: 1.9 (1.2-2.8); P = 0.0033). Through week 12, across STOP-HS1/STOP-HS2, serious treatment-emergent adverse events (AEs) occurred in 1-2% of patients across povorcitinib doses and in 2-3% with placebo; through week 54, serious AEs occurred in 5%/6% of patients receiving 45-mg/75-mg povorcitinib, respectively. The most frequent AEs among patients treated with 45-mg/75-mg povorcitinib were acne (17%/20%), nasopharyngitis (10%/12%) and upper respiratory tract infection (11%/10%). One death of undetermined etiology was reported and deemed unrelated to treatment. No new or unexpected safety findings were identified. Oral povorcitinib demonstrated significant improvements in HiSCR50 versus placebo and a favorable safety profile in patients with moderate to severe HS. ClinicalTrials.gov registration: NCT05620823 and NCT05620836 .
