|The following article features coverage from the European Hematology Association (EHA) 2021 Virtual Congress. Click here to read more of Cancer Therapy Advisor‘s conference coverage.|
Acalabrutinib demonstrated noninferior progression-free survival (PFS) and less toxicity when compared with ibrutinib in patients with previously treated chronic lymphocytic leukemia (CLL) in a phase 3 study.
Results from the study, ELEVATE-RR (ClinicalTrials.gov Identifier: NCT02477696), were presented at the European Hematology Association (EHA) 2021 Virtual Congress by Peter Hillmen, MB ChB, PhD, of the University of Leeds School of Medicine in the United Kingdom.
ELEVATE-RR is the first head-to-head trial that compared the safety and efficacy of BTK inhibitors, acalabrutinib and ibrutinib, in patients with previously treated CLL and del(17p) or del(11q).
A total of 533 patients were assigned to the acalabrutinib arm (n = 268) or ibrutinib arm (n = 265). At baseline, the patients’ median age was 66 years, and they had received a median of 2 prior therapies. Overall, 45.2% of patients had del(17p), and 64.2% had del(11q).
At a median follow-up of 40.9 months, acalabrutinib demonstrated noninferiority to ibrutinib for PFS. The median PFS was 38.4 months in both arms (hazard ratio [HR], 1.00; 95% CI, 0.79-1.27).
The rates of Richter’s transformation were comparable in the ibrutinib and acalabrutinib arms — 4.9% and 3.8%, respectively.
The median overall survival was not reached in either arm (HR, 0.82; 95% CI, 0.59-1.15). There were 63 (23.5%) deaths in the acalabrutinib arm and 73 (27.5%) deaths in the ibrutinib arm.
The rate of atrial fibrillation/flutter of any grade was significantly lower with acalabrutinib than with ibrutinib — 9.4% and 16.0%, respectively (P =.02).
The time to onset for any grade atrial fibrillation was longer for acalabrutinib than for ibrutinib — 28.8 months and 16.0 months, respectively. Atrial fibrillation led to treatment discontinuation in 7 patients on ibrutinib but none of the patients on acalabrutinib.
Aside from atrial fibrillation, other adverse events that occurred more frequently with ibrutinib included diarrhea, arthralgia, hypertension, confusion, bleeding, and interstitial lung disease/pneumonia. Headache and cough were more common with acalabrutinib.
Rates of grade 3 or higher infection were similar in the acalabrutinib and ibrutinib arms — 30.8% and 30.0%, respectively.
Adverse event-related treatment discontinuation occurred in 14.7% of patients in the acalabrutinib arm and 21.3% of patients in the ibrutinib arm.
“These results demonstrate that acalabrutinib is better tolerated and has similar efficacy to ibrutinib in patients with previously treated CLL,” Dr Hillmen said.
Disclosures: This research was supported by Acerta Pharma. The presenter declared affiliations with Janssen, AbbVie, Roche, Pharmacyclics, Gilead, AstraZeneca, and Apellis.
Read more of Cancer Therapy Advisor’s coverage of the EHA 2021 Virtual Congress by visiting the conference page.
Hillmen P, Byrd J, Ghia P, et al. First results of a head-to-head trial of acalabrutinib versus ibrutinib in previously treated chronic lymphocytic leukemia. Paper presented at: European Hematology Association 2021 Virtual Congress; June 2021; Abstract S145.