R-DHAP Followed by Allo-HCT Reasonable for High-risk CLL

R-DHAP (rituximab, dexamethasone, cytarabine, cisplatin) followed by allogeneic hematopoietic cell transplantation (allo-HCT) is a reasonable treatment option for patients with high-risk chronic lymphocytic leukemia (CLL) who are resistant to targeted therapies, a study published in the journal Bone Marrow Transplantation has shown.¹

Targeted therapies like ibrutinib and idelalisib have revolutionized the treatment of patients with CLL, but allo-HCT remains the only curative option for these patients. Because there is no standard remission-induction regimen for patients with active disease at time of allo-HCT, researchers sought to prospectively assess outcomes after R-DHAP followed by allo-HCT.

For the study, researchers enrolled 46 patients who were relapsed/refractory less than 1 year after fludarabine therapy or less than 2 years after fludarabine-based immunochemotherapy or relapsed/refractory with del(17p).

Of those, 29 received 3 or more cycles of R-DHAP and 16 received less than 3 cycles, either due to disease progression, toxicity, or toxic deaths.

Results showed that the overall response rate to R-DHAP was 58%, and 31 patients proceeded to allo-HCT following conditioning with fludarabine and 2 Gy total body irradiation.

Of the 31 patients who underwent transplantation, 20 (65%) were progression-free at 2 years after allo-HCT, including 17 without minimal residual disease.

After a median follow-up of 35.5 months, researchers found that the 2-year progression free survival and overall survival in the intention-to-treat population of 46 patients was 42% and 51%, respectively.

The study also demonstrated that harboring a del(17p) mutation or being refractory to fludarabine had no impact on outcomes in these patients.

Reference

1. van Gelder M, van Oers MH, Alemayehu WG, et al. Efficacy of cisplatin-based immunochemotherapy plus alloSCT in high-risk chronic lymphocytic leukemia: final results of a prospective multicenter phase 2 HOVON study [published online ahead of print February 15, 2016]. Bone Marrow Transplant. doi: 10.1038/bmt.2016.9.