Augmentation of oral methoxsalen-photochemotherapy with an oral retinoic acid derivative

Abstract

To improve the efficacy and reduce potential longterm hazards of photochemotherapy, the authors treated 36 patients with severe plaque-type psoriasis with a combination of oral methoxsalen-photochemotherapy (PUVA) and another oral chemotherapeutic agent, a retinoic acid derivative. Two groups of patients thus treated were cleared with 9.7 ± 4 treatments within 17.3 ± 7.6 days, and 6.3 ± 3.5 treatments within 11.0 ± 6.7 days, respectively; by contrast, 59 control patients treated with standard PUVA required 14.3 ± 7.8 treatments and 27.8 ± 15.2 days for clearing. Total cumulative doses of UVA energy required for clearing were 93.2 (mean) Joules/cm2 for PUVA, and 36.2 (mean) Joules/cm2 and 22.6 (mean) Joules/cm2, respectively, for the 2 patient groups receiving the combined treatment. 12 patients with severe palmoplantar psoriasis were cleared with 7 ± 3 treatments within 12.8 ± 5.5 days, requiring 21.4 ± 17.3 Joules/cm2. The combined treatment also cleared 11 patients who had been PUVA-treatment failures. The combined treatment thus considerably decreases the total energy of UVA required for PUVA alone; it accelerates the response of psoriasis to PUVA; and it is effective in the small group of patients who have to be considered PUVA failures. It is therefore more effective than PUVA and since it reduces the energy requirements of PUVA therapy it may diminish potential long-term hazards of this treatment.