Results of a prospective phase II trial with oral low-dose bexarotene plus photochemotherapy (PUVA) in refractory and/or relapsed patients with mycosis fungoides.

INTRODUCTION: Bexarotene is a synthetic retinoid effective in early and advanced stages of mycosis fungoides (MF)/Sezary Syndrome (SS) both in monotherapy and combination schemes. We aimed to assess disease response to low-dose bexarotene and PUVA in maintenance in refractory and/or resistant patients with early and advanced stage MF/SS.

METHODS: We followed prospectively 21 patients (stages IB-IV): 15 with early stage MF and 6 with advanced disease. "Mini" and standard protocols were respectively applied to patients who failed PUVA or several systemic regimens. The dose of bexarotene and the administration of PUVA were titrated individually and tailored during induction and maintenance according to previous therapy, disease stage and toxicity. We evaluated overall response (OR) at the end of maintenance, safety and event-free survival (EFS).

RESULTS: After induction phase, OR was 85.6%, higher in early MF (93.4%) than in advanced disease (66.6%). At the end of maintenance, OR was 76.2%, including 33.3% of CR. Median EFS for the whole group was 31 months. Bexarotene was well tolerated regarding the side effects, with prophylaxis and progressive drug increase in the induction phase of the protocol. Side effects were mainly of low and moderate grades.

CONCLUSIONS: We observed a favorable rate of therapeutic effects and few, generally mild, side effects with low doses of bexarotene combined with PUVA.