Longitudinal follow up of a phase 2 trial of venetoclax added to hyper-CVAD, nelarabine and pegylated asparaginase in patients with T-cell acute lymphoblastic leukemia and lymphoma

Optimal frontline use of active agents in T-cell acute lymphoblastic leukemia/lymphoma (T-ALL/LBL) is prudent to improve outcomes. We report the long-term follow-up of the phase 2 trial of HyperCVAD with nelarabine and pegylated asparaginase (Original cohort). In the latest protocol iteration venetoclax was added to the induction/consolidation regimen (Venetoclax cohort). Eligible patients were adults with untreated T-ALL/LBL or after minimal therapy and with adequate organ function. Primary endpoint of this analysis was improvement in 2-year progression free survival (PFS) and overall survival (OS) with venetoclax. From Aug 2007 to Dec 2024, 145 patients, at a median age of 35.4 years, were treated; 46 (33.8%) were in the venetoclax cohort. At median follow-up (mFU) of 62.4 months, 5-year PFS, duration of response (DOR), and OS were 63.7%, 72.0% and 66.2% respectively. In the venetoclax cohort (mFU 24.4 months) 2-year PFS (87.9% versus 64.1%, p = 0.03) and 2-year DOR (93.6% versus 69.2%, p = 0.005) were superior to the original cohort (mFU 89.4 months) and 2-year OS appeared better (87.8% versus 73.9%, p = 0.16). Febrile neutropenia was the most common serious adverse event, seen in 60% patients. The addition of venetoclax to HyperCVAD-nelarabine-pegylated asparaginase was tolerable and led to improvement in DOR and PFS.