HiSCR (Hidradenitis Suppurativa Clinical Response): a novel clinical endpoint to evaluate therapeutic outcomes in patients with hidradenitis suppurativa from the placebo-controlled portion of a phase 2 adalimumab study

Abstract

Background: Determining treatment response for patients with hidradenitis suppurativa (HS) can be challenging due to limitations of current disease activity evaluations.

Objective: Evaluate the novel, validated endpoint, Hidradenitis Suppurativa Clinical Response (HiSCR) and its utility as an outcome measure.

Methods: Patients with baseline total abscess and inflammatory nodule count (AN count) of at least three and draining fistula count of 20 or fewer comprised the post hoc subpopulation analysed. HiSCR (at least a 50% reduction in total AN count, with no increase in abscess count, and no increase in draining fistula count relative to baseline) and HS-PGA Response [Hidradenitis Suppurativa-Physician's Global Assessment score of clear, minimal, or mild, with at least a 2-grade improvement from baseline] were used to evaluate patient response after adalimumab treatment weekly, every other week, or placebo (1 : 1 : 1).

Results: The subpopulation included 132 (85.7%) patients; 70.5% women and 73.5% white. At week 16, HiSCR was achieved by 54.5% receiving weekly adalimumab, 33.3% every other week, and 25.6% placebo and HS-PGA Response was achieved by 20.5% receiving weekly adalimumab, 6.7% every other week and 2.3% placebo.

Conclusion: HiSCR was more responsive to change than HS-PGA Response in this subpopulation.

Figure 1

Achievement of HS‐PGA response, HiSCR and AN count improvement for the subpopulation during Period 1: (a) proportion of subpopulation achieving HS‐PGA response. For ADA ew vs. PBO: *P = 0.010 at weeks 12 and 16. (b) Proportion of subpopulation achieving response by HiSCR. For ADA ew vs. PBO: *P < 0.001 at weeks 2, 4 and 12; *P = 0.007 at week 16; For ADA eow vs. PBO: †P = 0.009 at week 4 and †P = 0.042 at week 12. (c) proportion of subpopulation achieving AN50, AN75 and AN100. For ADA ew vs. PBO: AN50, *P = 0.005 at week 12 and *P = 0.050 at week 16; AN75, *P = 0.033 at week 12; AN100, *P = 0.018 at week 12 and *P = 0.010 at week 16. (d) Mean (SE) percent improvement in AN count; *P ≤ 0.001 for ADA ew vs. PBO at weeks 12 and 16. Non‐responder imputation. HS‐PGA Response, Hidradenitis Suppurativa‐Physician Global Assessment score of clear, minimal, or mild, with at least a 2‐grade improvement from baseline; HiSCR, Hidradenitis Suppurativa Clinical Response; AN, abscesses and inflammatory nodules; PBO, placebo; ADA, adalimumab; eow, every other week; ew, every week.

Figure 2

Time to HiSCR for the subpopulation during Period 1 in (a) all patients, (b) patients at Hurley Stage I/II and (c) patients at Hurley Stage III. P‐values from stratified log‐rank test. Patients who did not achieve HiSCR during Period 1 were censored at the last Period 1 assessment. PBO, placebo; eow, every other week; ew, every week; NE, not estimable.