Long-term efficacy and safety of brodalumab in psoriasis through 120 weeks and after withdrawal and retreatment: subgroup analysis of a randomized phase III trial (AMAGINE-1)

BACKGROUND: Brodalumab is efficacious for the treatment of moderate-to-severe plaque psoriasis through 52 weeks. OBJECTIVES: To evaluate the efficacy and safety of brodalumab through 120 weeks, including following withdrawal and retreatment. METHODS: At baseline, patients were randomized to brodalumab (n = 222) or placebo (n = 220). At week 12, patients achieving a static Physician's Global Assessment (sPGA) score of 0 or 1 (sPGA 0/1) with brodalumab were rerandomized to brodalumab (n = 83) or placebo (n = 84; later re-treated with brodalumab if sPGA ≥ 3 occurred), and patients receiving placebo switched to brodalumab (n = 208). Safety was assessed by exposure-adjusted rates of treatment-emergent adverse events. RESULTS: Among those who achieved sPGA 0/1 at week 12 and were rerandomized to brodalumab, 96% and 80% using observed data, respectively, and 74% and 61% using nonresponder imputation, respectively, achieved 75% improvement in Psoriasis Area and Severity Index (PASI 75) and PASI 100 at week 120. Following withdrawal from brodalumab, return of disease occurred after a mean ± SD duration of 74·7 ± 50·5 days. Among those who switched from brodalumab to placebo at week 12, PASI 75 rates using observed data and nonresponder imputation were 55% and 51% at week 20, respectively and 94% and 75% at week 120, respectively; PASI 100 rates at week 120 were 75% and 60%, respectively. Efficacy was maintained through week 120 in those receiving brodalumab after placebo. No new safety signals were observed. CONCLUSIONS: These findings indicate that brodalumab is efficacious and safe for continuous long-term treatment of psoriasis, and support the potential for response after discontinuation and retreatment.