Efficacy and Safety of Itolizumab, a Novel Anti-CD6 Monoclonal Antibody, in Patients with Moderate to Severe Chronic Plaque Psoriasis: Results of a Double-blind, Randomized, Placebo-controlled, Phase-III Study

Background: Itolizumab, a humanized monoclonal antibody to CD6, is a novel therapeutic agent evaluated in chronic plaque psoriasis.

Objective: We sought to assess the safety and efficacy of itolizumab in moderate to severe chronic plaque psoriasis.

Methods: A total of 225 patients were randomized (2:2:1) to 2 different itolizumab arms (A or B; A = 4-week loading dose of 0.4 mg/kg/wk followed by 1.6 mg/kg every 2 weeks; B = 1.6/mg every 2 weeks) or placebo. At week 12, the placebo arm was switched to 1.6 mg/kg itolizumab every 2 weeks. The primary end point was the proportion of patients with at least 75% improvement in Psoriasis Area and Severity Index score at week 12.

Results: At week 12, 27.0% in arm A (P = .0172 vs placebo), 36.4% in B (P = .0043 vs placebo), and 2.3% in the placebo arm had at least 75% improvement in Psoriasis Area and Severity Index score. At week 28, the proportion with at least 75% improvement in Psoriasis Area and Severity Index score was comparable: 46.1%, 45.5%, and 41.9% for A, B, and placebo, respectively. In weeks 1 to 12, the incidence of all adverse events was comparable across arms (A, 43%; B, 38%; placebo, 47%) and the incidence of infections was not greater than placebo (11.1%, 8.9%, and 18.6% for A, B, and placebo).

Limitations: No active comparator is a limitation.

Conclusions: Itolizumab is an effective and well-tolerated novel biological therapy in moderate to severe psoriasis.