1.
Ibrutinib as a salvage therapy after allogeneic HCT for chronic lymphocytic leukemia
Michallet, M., Dreger, P., Sobh, M., Koster, L., Hoek, J., Boumendil, A., Scheid, C., Fox, C. P., Wulf, G., Kruger, W., et al
Bone marrow transplantation. 2019
Abstract
The purpose of our study is to provide information on safety and efficacy of ibrutinib as salvage treatment after allo-HSCT for CLL. A total of 56 patients were included, 36 (64%) males; median age at transplantation was 48 years (range: 35-64) and the median number of treatment lines prior to transplantation was 3 (1-10). The median time between allo-HSCT and Ibrutinib was 30 months (range: 1-140). Overall, 40 (71%) patients responded to Ibrutinib; 23 (41%) PR, and 17 (30%) CR. At time of ibrutinib initiation, ten patients had active chronic GVHD that resolved under Ibrutinib, whilst a single patient developed limited de novo chronic GVHD on Ibrutinib. Fourteen patients discontinued ibrutinib, four because of toxicity and ten because of disease progression. Overall, 14 patients progressed (median PFS = 24 months) among them 10 died. Two-year OS and PFS probabilities were 72% (95% CI: 52-84) and 50% (95% CI: 32-66), respectively. Patients with late relapse after allo-HSCT (≥24 months) had a better PFS after ibrutinib. Our study shows that ibrutinib can be safely administered for CLL relapse after allo-HSCT, with comparable efficacy to non-transplanted patients with high-risk disease.
2.
Ibrutinib for bridging to allogeneic hematopoietic cell transplantation in patients with chronic lymphocytic leukemia or mantle cell lymphoma: a study by the EBMT Chronic Malignancies and Lymphoma Working Parties
Dreger, P., Michallet, M., Bosman, P., Dietrich, S., Sobh, M., Boumendil, A., Nagler, A., Scheid, C., Cornelissen, J., Niederwieser, D., et al
Bone marrow transplantation. 2018
Abstract
The aim of this retrospective study was to investigate the safety and efficacy of allogeneic hematopoietic cell transplantation (alloHCT) in patients pre-treated with ibrutinib. Eligible were patients aged >18 years allotransplanted for chronic lymphocytic leukemia (CLL) or mantle cell lymphoma (MCL) after prior exposure to ibrutinib who were registered with the EBMT registry. Seventy patients (CLL 48, MCL 22) were included. At the time of alloHCT, 73% of the patients were ibrutinib responsive. All patients except one engrafted, and acute GVHD grade 2-4 (3-4) was observed in 49% (12%) of 68 evaluable patients. The cumulative incidence of chronic GVHD was 54% 1 year after transplant. In the CLL group, 12-month non-relapse mortality, relapse incidence (RI), progression-free survival (PFS), and overall survival (OS) were 10, 30, 60, and 72%, respectively, and in the MCL group 5, 19, 76, and 86%, respectively. Pre-transplant ibrutinib failure and poor performance status predicted inferior RI, PFS and OS in the CLL group. In conclusion, ibrutinib does not affect the safety of a subsequent alloHCT. While the relatively high post-transplant relapse risk in ibrutinib-exposed patients with CLL deserves further study, in patients with MCL consolidating disease responses to ibrutinib with alloHCT seems to be a promising option.