Continuous infliximab therapy achieves greater, longer-term efficacy than the same dose given as intermittent as-needed therapy in the treatment of moderate to severe plaque psoriasis.
The EXPRESS II (Evaluation of Infliximab for Psoriasis in a Remicade Efficacy and Safety Study) was designed to evaluate long-term safety and efficacy of continuous (over eight weeks) and intermittent (as needed) infliximab maintenance infusions.
A total of 835 adults with moderate to severe psoriasis who had not received infliximab treatment before (n=835) were randomised to induction therapy (weeks 0, 2 and 6) with infliximab 3mg/kg or 5mg/kg, or placebo. Infliximab-treated patients were randomised again at week 14 to continuous or intermittent maintenance regimens at their induction dose. Those in the as-needed group received treatment at visits during which oberved improvement in PASI from baseline was less than 75%, and received placebo if PASI improvement was at least 75%.
The primary efficacy endpoint was the proportion of patients achieving PASI 75 at week 10; PASI 90 was also assessed at week 50. At week 10, PASI 75 status was achieved by 7.03% and 75.5% of patients in the infliximab 3mg/kg and 5mg/kg induction groups, respectively, compared with 1.9% of patients in the placebo group. In the PASI 75 responders, longer-term response was better maintained with continuous compared with intermittent therapy within each dose, and with 5mg/kg compared with 3mg/kg continuous therapy.