Is Ibrutinib of Benefit for High-Risk, Treatment-Naive Patients With CLL?
Posted: Friday, October 29, 2021
Although the Bruton’s tyrosine kinase (BTK) inhibitor ibrutinib is a preferred treatment for many patients with chronic lymphocytic leukemia (CLL), there is limited evidence as to its effects among patients with 17p deletion or TP53 mutations. Results of a phase II trial, published in Blood, suggested that ibrutinib may improve outcomes in this high-risk patient population. The report indicated that BTK inhibitor therapy should serve as a preferred treatment for these patients outside of clinical trials, although larger clinical studies are necessary to validate their results.
“Our data demonstrate that front-line therapy with ibrutinib results in long-term remissions in high-risk [patients with CLL] with 17p deletion and/or TP53 mutations, corroborating recent data that BTK inhibitor monotherapy is providing durable remissions in this high-risk population,” Jan A. Burger, MD, PhD, of The University of Texas MD Anderson Cancer Center, Houston, and colleagues concluded.
The research team randomly assigned 27 treatment-naive patients with CLL who had 17p deletion or TP53 mutations to receive ibrutinib monotherapy (n = 15) or ibrutinib plus rituximab (n = 12). After a median follow-up of 70 months, one-third of the patients remained in the study.
The median overall survival and progression-free survival were not reached. However, the estimated 6-year progression-free and overall survival rates were 60% and 79%, respectively; the authors considered this a “marked improvement” compared with previous studies evaluating 5-year survival results of fludarabine, cyclophosphamide, and rituximab. The overall response rate was similar between patients who received ibrutinib monotherapy and ibrutinib plus rituximab (93.3% vs. 100%, respectively). All but a single patient achieved an objective response. Of note, the duration of remission was no different between patients who achieved a complete response (n = 10) or a partial response (n = 16), suggesting that deep remissions may not be a prerequisite for durable remissions.
Disclosure: For full disclosures of the study authors, visit sciencedirect.com.
