Efficacy and safety of adalimumab in Chinese patients with moderate-to-severe plaque psoriasis: results from a phase 3, randomized, placebo-controlled, double-blind study

Abstract

Background: This phase 3 trial is the first to evaluate the efficacy and safety of treatment with the systemic TNF-α inhibitor, adalimumab, for Chinese patients with moderate-to-severe plaque psoriasis.

Methods: In the 12-week, double-blind, placebo-controlled Period A, patients were randomized 4 : 1 to receive adalimumab 40 mg every-other-week (following a single 80 mg dose), or placebo every-other-week. In the subsequent 12-week, open-label, Period B, all patients received adalimumab 40 mg every-other-week starting at week 13, following a single, blinded dose at week 12 of adalimumab 80 mg or matching placebo (for patients receiving placebo or adalimumab in Period A respectively). In Period A, efficacy was analysed for all randomized patients and safety for all patients receiving ≥1 dose of the study drug.

Results: For the 425 patients in this study (87 placebo; 338 adalimumab), a higher percentage randomized to adalimumab achieved the primary endpoint of ≥75% improvement from baseline in PASI score (PASI 75) at week 12: placebo 11.5% (10/87); adalimumab 77.8% (263/338; P < 0.001). Physician's Global Assessment of clear to minimal was achieved at week 12 by 14.9% placebo (13/87) and 80.5% adalimumab (272/338; P < 0.001). For patients who received adalimumab at any time during the study (All-adalimumab Population), treatment-emergent adverse events (AEs) were reported by 63.4%; the most common was upper respiratory infection (16.1%). Serious AEs were reported by 3.5% of the All-adalimumab Population, and serious infectious AEs by 1.2%, which include lung infection, pneumonia and tuberculosis [2 (0.5%) patients each]. There was one death (chronic heart failure).

Conclusion: In these Chinese patients with moderate-to-severe psoriasis, a significantly greater percentage treated with adalimumab compared with placebo achieved efficacy endpoints at week 12 and efficacy was sustained to week 24. Safety results were consistent with the known adalimumab safety profile; no new safety signals were identified in the 24 weeks of treatment.

Figure 1

PASI 75, 90 and 100 Response Rate. (a) PASI 75. *P = 0.002 week 3; P < 0.001 weeks 7 and 12. 95% CIs: week 3 [6.6, 12.9]; week 7 [36.8, 49.1]; week 12 [58.3, 74.4]. (b) PASI 90. *P < 0.001. 95% CIs: week 7 [18.9, 27.9]; week 12 [45.6, 58.7]. (c) PASI 100. *P = 0.001. 95% CI: week 12 [7.9, 16.4]. Non‐responder imputation. ADA, adalimumab 40 mg every‐other‐week dosing; CIs, confidence intervals; ITT_A, all randomized patients; ITT_B, all patients receiving at least one dose of study drug in Period B; PASI, Psoriasis Area Severity Index; PBO, placebo.

Figure 2

PASI 75 Response at week 12 for Patient Subgroups (ITT_A Population). (a) *P < 0.001. 95% CIs: median bodyweight (kg) <69 [61.1, 80.8] and ≥69 [47.2, 74.0]; median BMI (kg/m2) <25 [60.5, 78.6] and ≥25 [42.1, 75.3]. Non‐responder imputation. (b) *P < 0.001. 95% CIs: age (years) <40 [53.9, 80.5] and ≥40 [55.6, 75.8]; male [61.6, 80.0] and female [38.0, 70.1]; median duration of psoriasis (years) <12.8 [53.2, 76.2] and ≥12.8 [56.7, 79.1]; psoriatic arthritis at baseline, yes [48.3, 77.2] and no [58.2, 75.8]. Non‐responder imputation. ^a N = 10. ADA, adalimumab 40 mg every‐other‐week dosing; BMI, body mass index; CI, confidence intervals; PASI, Psoriasis Area Severity Index; PBO, placebo; PsA, psoriatic arthritis.