Outcomes in chronic lymphocytic leukemia patients on novel agents in the US Veterans Health Administration System.

The US veteran population has a high proportion of chronic lymphocytic leukemia (CLL) risk factors. Using the Veterans Health Administration (VHA) population, we conducted a retrospective chart review of 1205 CLL patients who initiated treatment with a novel oral agent. For 1L ibrutinib, 33% (n = 107) discontinued therapy during the study, of which 64% discontinued due to adverse events (AEs). For relapsed/refractory (R/R) ibrutinib, 35% (n = 262) discontinued therapy, of which 63% discontinued due to AEs. For R/R venetoclax, 31% (n = 27) discontinued therapy, of which 41% were due to AEs. For idelalisib, 84% (n = 41) discontinued therapy, of which 54% were due to AEs. This real-world study suggests that AEs play an important role in dose reductions and discontinuations; however, physician inexperience in using these drugs when they were first introduced could be part of what is leading to these negative outcomes.

Persistent leukocytosis in polycythemia vera is associated with disease evolution but not thrombosis.

There are unresolved questions regarding the association between persistent leukocytosis and risk of thrombosis and disease evolution in polycythemia vera (PV), as much of the published literature on the topic does not appropriately use repeated-measures data or time-dependent modeling to answer these questions. To address this knowledge gap, we analyzed a retrospective database of 520 PV patients seen at 10 academic institutions across the United States. Taking hematologic laboratory data at ∼3-month intervals (or as available) for all patients for duration of follow-up, we used group-based trajectory modeling to identify latent clusters of patients who follow distinct trajectories with regard to their leukocyte, hematocrit, and platelet counts over time. We then tested the association between trajectory membership and hazard of 2 major outcomes: thrombosis and disease evolution to myelofibrosis, myelodysplastic syndrome, or acute myeloid leukemia. Controlling for relevant covariates, we found that persistently elevated leukocyte trajectories were not associated with the hazard of a thrombotic event (P = .4163), but were significantly associated with increased hazard of disease evolution in an ascending stepwise manner (overall P = .0002). In addition, we found that neither hematocrit nor platelet count was significantly associated with the hazard of thrombosis or disease evolution.