Long-term efficacy and safety of alemtuzumab in advanced primary cutaneous T-cell lymphomas

Summary Background Alemtuzumab has been proposed as salvage therapy for refractory cutaneous T‐cell lymphomas (CTCLs). Long‐term follow‐up data are scarce. Objectives To assess the efficacy and safety of alemtuzumab in the treatment of advanced CTCL. Methods A multicentre retrospective analysis was carried out of 39 patients with advanced CTCL treated with alemtuzumab between 2003 and 2013. Results Thirty‐nine patients (median age 62 years, range 20–83) with Sézary syndrome (SS, n = 23) or advanced mycosis fungoides (MF, n = 16) received alemtuzumab 30 mg two to three times per week for a median duration of 12 weeks (range 1–35). Fifteen patients received maintenance therapy for a median duration of 24 weeks (range 6–277). Eleven patients (28%) had transformed disease (MF, n = 10; SS, n = 1). After a median follow‐up of 24 months (range 0·3–124), eight patients (21%) were still alive. The overall response rate was 51% in the whole study group (partial response, n = 13; complete response, n = 7); 70% in patients with SS and 25% in patients with MF (P = 0·009). The median time to progression was 3·4 months (range 0·4–42). Six patients (15%; SS, n = 5; MF, n = 1) remained progression free for > 2 years (median 56 months, range 28–117). Five patients experienced cutaneous large T‐cell transformation during alemtuzumab treatment and one patient developed primary cutaneous large B‐cell lymphoma. Twenty‐four patients (62%) had a grade three or higher infectious adverse event and 10 (26%) a haematological toxicity, which led to treatment discontinuation in 17 cases (44%) and death in two (5%). Conclusions Alemtuzumab may induce long‐term remission in SS but seems ineffective in MF and transformed CTCL. What's already known about this topic? Alemtuzumab has shown short‐term efficacy in small numbers of patients with advanced primary cutaneous T‐cell lymphomas. What does this study add? Alemtuzumab may induce long‐term remission (> 2 years) in patients with Sézary syndrome. Alemtuzumab is poorly effective in nontransformed mycosis fungoides and transformed CTCL.