Rituximab-based allogeneic transplant for chronic lymphocytic leukemia with comparison to historical experience.
Shadman, M., D. G. Maloney, B. Storer, B. M. Sandmaier, T. R. Chauncey, N. Smedegaard Andersen, D. Niederwieser, J. Shizuru, B. Bruno, M. A. Pulsipher, R. T. Maziarz, E. D. Agura, P. Hari, A. A. Langston, M. B. Maris, P. A. McSweeney, R. Storb and M. L. Sorror (2020). “Rituximab-based allogeneic transplant for chronic lymphocytic leukemia with comparison to historical experience.” Bone Marrow Transplant 55(1): 172-181.
Relapse of chronic lymphocytic leukemia (CLL) after allogeneic hematopoietic cell transplantation (HCT) remains a clinical challenge. We studied in a phase II trial whether the addition of peri-transplant rituximab would reduce the relapse risk compared with historical controls (n = 157). Patients (n = 55) received fludarabine and low-dose total body irradiation combined with rituximab on days -3, + 10, + 24, + 36. Relapse rate at 3 years was significantly lower among rituximab-treated patients versus controls (17% versus 31%; P = 0.04). Overall survival (OS), progression-free survival (PFS) and nonrelapse mortality (NRM) were statistically similar: (53% versus 50%; P = 0.8), (44% versus 42%; P = 0.63), and (38% versus 28%; P = 0.2), respectively. In multivariate analysis, rituximab treatment was associated with lower relapse rates both in the overall cohort [hazard ratio (HR): 0.34, P = 0.006] and in patients with high-risk cytogenetics (HR: 0.21, P = 0.0003). Patients with no comorbidities who received rituximab conditioning had an OS rate of 100% and 75% at 1 and 3 years, respectively, with no NRM. Peri-transplant rituximab reduced relapse rates regardless of high-risk cytogenetics. HCT is associated with minimal NRM in patients without comorbidities and is a viable option for patients with high-risk CLL. Clinical trial information: NCT00867529.