Overview
Patients aged ≤55 years represent a small minority of individuals with chronic lymphocytic leukemia (CLL). This study compared biological features, frontline treatment patterns, and real-world outcomes between younger (≤55 years, n=520) and older (>55 years, n=6,294) patients initiating first-line BTK inhibitor or BCL2 inhibitor therapy in the US Flatiron Health Research Database between 2019 and 2026.
Younger patients presented with higher Rai stages (44.5% vs 31.2% stage II–IV), higher Black representation (15% vs 8.2%), and higher rates of unmutated IGHV (59% vs 54%) and del(11q) (21% vs 17%), but lower rates of TP53 mutation (8.1% vs 17%) and del(17p) (8.5% vs 12%) among patients with available testing. On multivariable analysis, younger age was independently associated with longer time to next treatment (5-year rate: 52% vs 43%) and longer overall survival (5-year rate: 92% vs 69%).
Why this matters
This study provides contemporary real-world benchmarks for younger adults with CLL receiving frontline targeted therapies. Despite differences in disease characteristics and treatment selection, younger age was independently associated with longer time to next treatment and overall survival. These findings help characterize outcomes in a population that remains understudied in the targeted therapy era and highlight the need for further research into treatment selection, sequencing, and long-term survivorship.