Two-inhibitor salvage therapy for hairy cell leukemia

In this issue of Blood, Kreitman and colleagues1 report the results of treat-ment with dabrafenib plus trametinib in a cohort of patients with relapsed/ refractory BRAF V600E mutation-positive hairy cell leukemia. This cohort was from a multicenter, open-label, nonrandomized phase 2 basket study of dabrafenib plus trametinib in patients with BRAF V600E mutation-positive rare cancers. The patients registered to this trial had been extensively pre-treated with standard agents used for hairy cell leukemia. All patients had been treated with purine analogs (either pentostatin or cladribine) and had relapsed or progressed. Most patients underwent at least 2 prior regimens. Prior treatment regimens included multiple agents. For example, 63% of patients had received rituximab, and 20% had received moxetumomab. In this extensively pretreated patient group, the overall response to dabrafe-nib plus trametinib was 89.1% with 65.5% achieving complete remission. Patients were continued on therapy until unacceptable toxicity, disease progression, or death occurred.

Automated summary

In this study, the authors investigated the efficacy of dabrafenib plus trametinib in treating relapsed/refractory BRAF V600E mutation-positive hairy cell leukemia. They enrolled extensively pre-treated patients who had already received standard agents for hairy cell leukemia. The overall response rate to the combination therapy was 89.1%, with 65.5% of patients achieving complete remission. Patients continued treatment until unacceptable toxicity, disease progression, or death occurred.