Adalimumab for moderate to severe chronic plaque psoriasis: efficacy and safety of retreatment and disease recurrence following withdrawal from therapy

Summary Background  Adalimumab is effective for moderate to severe chronic plaque psoriasis; however, data regarding retreatment following withdrawal and subsequent relapse are limited. Objectives  To evaluate the efficacy and safety of adalimumab if interrupted and then resumed in patients with moderate to severe psoriasis. Methods  Patients in a long-term adalimumab open-label extension study (NCT00195676) who achieved a Physician’s Global Assessment (PGA) score of ‘Mild’ (2), ‘Minimal’ (1) or ‘Clear’ (0) were withdrawn from adalimumab and monitored for relapse to PGA of ‘Moderate’ (3) or worse. The subgroup of interest had stable psoriasis control, defined as PGA of 0/1 for ≥ 12 weeks on every other week (eow) dosing before withdrawal. Relapsing patients were retreated with adalimumab (80 mg at week 0 and 40 mg eow starting at week 1). PGA, Psoriasis Area and Severity Index responses, fatigue, pharmacokinetics and immunogenicity were assessed. Results  In total, 525 patients were withdrawn from adalimumab; the subgroup with stable psoriasis control comprised 285 patients. Of these, 178 relapsed (median = 141 days) before treatment reinitiation and 107 did not relapse. Patients without relapse by 40 weeks off therapy reinitiated adalimumab. Rates of PGA 0/1 after 16 weeks of adalimumab retreatment were 89% for patients without relapse and 69% for patients who relapsed. Relapsers experienced significantly less fatigue after retreatment. Nine patients (3%) had serious adverse events (two were infections). No rebound or allergic reactions occurred. Conclusions  Adalimumab-treated patients who discontinued therapy and subsequently relapsed had a good likelihood of regaining clinical efficacy following adalimumab reinitiation.