Background  REVEAL was a 52-week study of adalimumab for moderate to severe psoriasis. At Week 33, adalimumab-treated patients with sustained responses (PASI ≥75 at Weeks 16 and 33) were re-randomized to receive adalimumab or placebo. Subsequently, they could receive adalimumab in an open-label extension (OLE) study.

Objective  To compare long-term efficacy and safety of adalimumab 40 mg every other week (eow), given as continuous treatment or with one period of interruption followed by retreatment.

Methods  Patients who were re-randomized to adalimumab or placebo at REVEAL Week 33 and received ≥1 dose of OLE adalimumab were analysed as the continuous and retreatment groups, respectively, for >2 years of OLE treatment with adalimumab 40 mg eow. LOCF was used for missing efficacy data.

Results  At OLE Weeks 0, 12 and 24, PASI 75 response rates were 84%, 84%, 86% with continuous treatment (= 233) vs. 45%, 71%, 79% with retreatment (= 227). Thereafter, efficacies were slightly greater for continuous treatment but similar between groups, with PASI 75 response rates at OLE Week 108 of 75% vs. 73% respectively. Retreatment was most effective for patients with ≥PASI 50 responses when retreatment was initiated. Adverse event rates for retreatment were equal to or lower than those for continuous treatment.

Conclusions  In psoriasis patients with sustained PASI 75 responses to adalimumab, long-term efficacy of retreatment after a ≤19-week interruption was similar to efficacy achieved with >3 years continuous treatment. Adalimumab retreatment provided the best results when initiated before responses had declined below PASI 50.