Disease Progression and Clinical Outcomes Among Patients With CLL Receiving Ibrutinib

Among patients with chronic lymphocytic leukemia (CLL) with disease progression who were treated with ibrutinib, overall survival (OS) was significantly longer when next-line treatment was chimeric antigen receptor T-cell therapy or venetoclax-based treatment compared to other approved treatments, which may suggest an unmet need for this increasing patient population (Blood Cancer J. 2022; 12(9):124. doi:10.1038/s41408-022-00721-6

Paul J Hampel, MD, Division of Hematology, Department of Medicine, Mayo Clinic, Rochester, MN, and colleagues evaluated outcomes of 144 patients with CLL treated at Mayo Clinic with 2018 iwCLL disease progression on ibrutinib. Treatment-free survival (TFS) was evaluated as the duration from the start of treatment immediately after ibrutinib failure to the initiation of the subsequent line of therapy or death, whichever occurred earlier. OS was examined as the time from date of progression while on ibrutinib and from subsequent therapy start date until date of death or last known to be alive.

Researchers discovered that the average OS for the entire cohort was 25.5 months. The median OS 29.8 months among patients with CLL progression (n = 104) and 8.3 months among those with Richter transformation (n = 38). Longer OS was observed among patients with CLL progression who had received ibrutinib in the frontline compared to relapsed/refractory setting (not reached vs 28.5 months; p = 0.04), but was comparable among patients treated with 1, 2, or ≥3 prior lines (18.5, 30.9, and 26.0 months, respectively, p = 0.24).

Moreover, among patients with CLL disease progression on ibrutinib, OS was meaningfully longer when next-line treatment was chimeric antigen receptor T-cell therapy (median not reached) or venetoclax-based treatment (median 29.8 months) compared to other approved treatments, such as chemoimmunotherapy, phosphoinositide 3’-kinase inhibitors, and anti-CD20 monoclonal antibodies (9.1 months; p = 0.03).

“These findings suggest an unmet need for this growing patient population,” the authors concluded.