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SATURDAYOctober 19SESSION 31:40 – 2:00 |
Jean-Marie Geiger Background and Objective Acitretin (Soriataneâ, Neotigasonâ) has proven efficacy in the symptomatic treatment of severe psoriasis. The efficacy of psoriasis therapy is typically measured using the Psoriasis Area Severity Index (PASI), which quantifies the severity of a patient’s condition based on both the percentage of body surface area affected and the lesion severity. PASI 50 and PASI 75, which refer to the percentage of patients achieving a 50% or 75% improvement in baseline PASI score, are increasingly used as efficacy endpoints in clinical trials. This retrospective analysis was undertaken to determine PASI 50 and PASI 75 response rates for two previously published acitretin clinical trials (1,2). Patients and Methods Study A (1): A total of 63 patients (42 men, 21 women) with severe psoriasis were enrolled in this multicentre Canadian trial. Treatment with acitretin was initiated at 50 mg/day for 4 weeks, followed by dosage adjustment according to therapeutic response for up to 12 months. Study B (2): This multicentre trial conducted in the four European Nordic countries was a double-blind comparison between acitretin and etretinate, but only patients who received acitretin are included in this evaluation. Treatment consisted of 4 weeks of therapy at 40 mg/day followed by an 8-week phase of dosage adjustment according to therapeutic response. A total of 118 patients (68 men, 50 women) with severe psoriasis were evaluable for efficacy. In both studies, efficacy was measured by PASI scores and Physician’s Global Assessment (PGA) at the end of treatment. Results After 12 weeks of treatment, PASI 50 response rates were 66% and 85% in the two studies, respectively, with corresponding PASI 75 response rates of 34% and 52%. In Study A, 89% of patients who completed the 12-month course of therapy were found to be PASI 50 responders, and 60% PASI 75 responders. Among the 63 patients enrolled, 76% achieved a PASI 50 response and 46% a PASI 75 response by the end of treatment (average duration: 267 days). PGA evaluations found 52.4% of patients to show “marked improvement”, 31.7% “moderate or slight improvement” and 15.9% “no change or worsening”. Of the patients showing “marked improvement”, 79% were PASI 75 responders. Of the 118 evaluable patients in Study B, 78% achieved PASI 50 and 47% PASI 75 by the end of therapy (average duration: 84 days). PGA evaluations found 80.5% to show “remission or marked improvement”, 13.6% “slight improvement” and 5.9 % “no change or worsening”. All patients who achieved PASI 75 showed remission or marked improvement. Discussion The high percentage of patients achieving a 50% or 75% reduction in PASI score during treatment with acitretin confirms the therapeutic efficacy of this drug. Although responder rates were slightly higher in study B than in study A at week 12, responder rates at the end of treatment were found to be similar in both trials, with around 75% of patients showing a 50% improvement in PASI and 50% an improvement of 75%. In both studies there was good correlation between PASI 75 response rates and PGA evaluations. 1. Murray HE et al. J Am Acad Derm 1991; 24: 598-602 2. Kragballe K et al. Acta Derm Venereol 1989; 69: 35-4 |