Varied responses to and efficacies of hydroxychloroquine treatment according to cutaneous lupus erythematosus subtypes in Japanese patients

Hydroxychloroquine is recommended as the first-line systemic treatment for cutaneous lupus erythematosus (CLE) in Western countries, and it was approved in Japan in 2016. However, the efficacy of hydroxychloroquine in various cutaneous lupus erythematosus subtypes in Japanese patients has not been elucidated to date. Therefore, we investigated the efficacy of hydroxychloroquine for the treatment of cutaneous manifestations according to CLE subtypes in Japanese patients. We enrolled 35 patients (29 diagnosed with systemic lupus erythematosus and six with CLE) in this retrospective study. We analyzed the efficacy of hydroxychloroquine for the treatment of cutaneous manifestations according to cutaneous lupus erythematosus subtypes, time to the first skin improvement, as well as effects on laboratory data and reduction of concomitant immunosuppressive drug administration at 16 and 32 weeks of therapy. Complete improvement was observed at high rates for acute CLE (ACLE); however, partial or non-improvement rates were higher for chronic CLE (CCLE) at 16 weeks. Several patients with alopecia without scarring achieved complete improvement at 32 weeks. CCLE tended to take more time to improve than ACLE. Overall, hydroxychloroquine was highly effective for skin: 87% of patients had at least some beneficial response at 16 weeks. Nevertheless, there were wide variations in complete improvement rates and duration for improvement among CLE subtypes. Our findings suggest that a therapeutic approach considering the subtypes of CLE will improve its management.