A real-world study evaluating drug tolerability and health care resource use with acalabrutinib vs ibrutinib in patients with relapsed/refractory chronic lymphocytic leukemia/small lymphocytic lymphoma.

BACKGROUND AND AIM: Bruton tyrosine kinase inhibitors (BTKis) are the standard of care for patients with relapsed/refractory (R/R) chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). Ibrutinib and acalabrutinib are two commonly used BTKis, though hypertension (HTN) and other cardiovascular medical events of interest (CV MEOIs) can impact treatment tolerability and long-term use. This study compared cardiovascular safety and health care resource use (HCRU) of acalabrutinib versus ibrutinib monotherapy for R/R CLL/SLL in real-world community practice.

METHODS

This retrospective comparative study included 270 RR CLL/SLL patients (90 acalabrutinib; 180 ibrutinib) treated from January 2017 through December 2023 across the ONCare Alliance Network, comprising 30 US community hematology practices. Endpoints included new or worsening of existing HTN, development of CV MEOIs, and treatment discontinuation due to adverse events. HCRU metrics consisted of emergency department visits, hospital admissions, length of stay, specialist consultations, and related medical procedures. Propensity score weighted multivariable logistic regression was used for the comparative analysis on the tolerability endpoints.

RESULTS

At a median follow-up of 33 months, patients treated with acalabrutinib had significantly fewer HTN events (OR = 0.27, 95% CI = 0.074-0.98; p = .046) and adverse events leading to treatment discontinuation (OR = 0.39, 95% CI = 0.20-0.73; p = .002) compared to those on ibrutinib. Hospital admission rates for MEOIs were lower in the acalabrutinib group (0.20 vs. 0.24 per patient), with a shorter median length of stay (3.0 vs. 6.0 days). Additionally, acalabrutinib patients had fewer specialist consultations (0.11 vs. 0.22 per patient) and associated medical procedures (0.11 vs. 0.18 per patient).

CONCLUSIONS

In R/R CLL/SLL, acalabrutinib demonstrated a more favorable cardiovascular safety profile than ibrutinib, with fewer HTN events and CV MEOIs. This translated into reduced hospital admissions and lower HCRU, supporting acalabrutinib as a potentially better tolerated long-term treatment option in community practice.