The Priority Review

Clinical trials

42.3 percent on povorcitinib reached HiSCR50 at Week 12 versus 28.6 percent on placebo

In the Phase 3 STOP-HS2 study of 619 participants with moderate to severe hidradenitis suppurativa, 42.3 percent on povorcitinib 45 mg and 42.3 percent on 75 mg reached HiSCR50 at Week 12, against 28.6 percent on placebo. Incyte Corporation's results are now posted in the trial registry.

By The Priority Review desk

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In STOP-HS2, a Phase 3 trial in moderate to severe hidradenitis suppurativa, 42.3 percent of participants on povorcitinib 45 mg and 42.3 percent on povorcitinib 75 mg reached HiSCR50 at Week 12, compared with 28.6 percent on placebo, the trial registry record shows. The sponsor, Incyte Corporation, enrolled 619 participants. Placebo-controlled results from the study are now posted.

HiSCR50 at Week 12 STOP-HS2, intent-to-treat population, 95% confidence intervals 0% 10% 20% 30% 40% 50% 60% Percentage of participants Placebo once daily (n = 203) 22.5% to 35.3% 28.6% Povorcitinib 45 mg once daily (n = 208) 35.5% to 49.3% 42.3% Povorcitinib 75 mg once daily (n = 208) 35.5% to 49.3% 42.3% HiSCR50 is at least a 50% reduction from baseline in the total abscess and inflammatory nodule count, with no increase from baseline in abscess or draining tunnel count. From the trial registry record NCT05620836, results first posted November 5, 2026. Dashed line marks the Placebo value. The Priority Review.
HiSCR50 at Week 12 STOP-HS2, intent-to-treat population, 95% confidence intervals 0% 10% 20% 30% 40% 50% 60% Percentage of participants Placebo once daily (n = 203) 22.5% to 35.3% 28.6% Povorcitinib 45 mg once daily (n = 208) 35.5% to 49.3% 42.3% Povorcitinib 75 mg once daily (n = 208) 35.5% to 49.3% 42.3% HiSCR50 is at least a 50% reduction from baseline in the total abscess and inflammatory nodule count, with no increase from baseline in abscess or draining tunnel count. From the trial registry record NCT05620836, results first posted November 5, 2026. Dashed line marks the Placebo value. The Priority Review.

Why it matters

The record's brief summary says the purpose of the study is to evaluate the efficacy and safety of povorcitinib (INCB054707) in participants with moderate to severe hidradenitis suppurativa (HS) over a 12-week placebo-controlled period, followed by a 42-week extension period. The registry lists the study as double-blind, randomized and placebo-controlled, with Phase 3 status and a quadruple masking design.

Primary results at Week 12

Results were first posted November 5, 2026. The measures below use the intent-to-treat population, defined in the record as all randomized participants, with missing values and participants on systemic treatment with potential effects on hidradenitis suppurativa outcomes counted as nonresponders.

  • HiSCR50 at Week 12: 28.6 percent on placebo (95% confidence interval 22.5 to 35.3), 42.3 percent on povorcitinib 45 mg (35.5 to 49.3) and 42.3 percent on povorcitinib 75 mg (35.5 to 49.3).
  • Povorcitinib 45 mg versus placebo: odds ratio 1.8 (95% confidence interval 1.2 to 2.8), p-value 0.0035; difference in response rate 13.8 (4.7 to 23.0).
  • Povorcitinib 75 mg versus placebo: odds ratio 1.9 (95% confidence interval 1.2 to 2.8), p-value 0.0033; difference in response rate 13.8 (4.7 to 22.9).
  • HiSCR75 at Week 12: 13.3 percent on placebo (9.0 to 18.8), 25.5 percent on 45 mg (19.7 to 32.0) and 28.4 percent on 75 mg (22.3 to 35.0).
  • Participants with a flare by Week 12: 33.5 percent on placebo (27.0 to 40.4), 21.6 percent on 45 mg (16.2 to 27.9) and 20.7 percent on 75 mg (15.4 to 26.8).

The analyses counted 203 participants on placebo, 208 on povorcitinib 45 mg and 208 on povorcitinib 75 mg in these analyses.

Study design

The registry describes participants as randomized 1:1:1 to povorcitinib Dose A, povorcitinib Dose B or placebo once a day. Participants who complete the 12-week placebo-controlled period may continue to a 42-week extension period with povorcitinib at Dose A or Dose B once a day. The results name the doses as 45 mg and 75 mg once daily. Povorcitinib and placebo are both oral tablets.

The record lists a study start of 2023-02-22, a primary completion date of 2025-01-07 and a study completion date of 2025-11-21, all marked actual.

Safety measures in the placebo-controlled period

The registry counts participants with at least one treatment-emergent adverse event (TEAE) in the safety population, defined as all participants who received at least one dose during the placebo-controlled period.

  • Participants with a TEAE: 99 of 203 on placebo, 130 of 208 on povorcitinib 45 mg and 131 of 207 on povorcitinib 75 mg.
  • Participants with a Grade 3 or higher TEAE: 5 on placebo, 8 on 45 mg and 6 on 75 mg.
  • Participants with serious adverse events: 5 of 203 on placebo, 4 of 208 on 45 mg and 4 of 207 on 75 mg. The record lists 0 deaths in each of those groups.

Extension period

In the extension, the record reports the placebo-to-povorcitinib groups separately, with 90 participants moving from placebo to 45 mg and 92 to 75 mg in the extension safety measure.

Sources