Posted: Thursday, July 14, 2022
At a median follow-up of 34 months, ibrutinib plus rituximab demonstrated superior progression-free and overall survival outcomes versus chemoimmunotherapy in patients with chronic lymphocytic leukemia (CLL), according to Tait D. Shanafelt, MD, of the Stanford University School of Medicine, California, and colleagues. The long-term follow-up data from the phase III E1912 trial, which were published in the journal Blood, further supported these findings in both IGHV-mutated and IGHV-unmutated populations.
In a 2:1 ratio, a total of 529 treatment-naive patients younger than age 70 were randomly assigned to receive ibrutinib plus rituximab or six cycles of fludarabine plus cyclophosphamide and rituximab. Follow-up data were provided for a median of 5.8 years.
The median progression-free survival was found to be superior with ibrutinib plus rituximab (hazard ratio [HR] = 0.37; P < .001); this seemed to hold true regardless of IGHV mutational status (mutated: HR = 0.27, P < .001; unmutated: HR = 0.27, P < .001). A total of 60.5% of patients who received ibrutinib plus rituximab remain on treatment with ibrutinib.
Disease progression or death (10.5%), adverse events or complications (21.9%), and other reasons (6.8%) led to the discontinuation of treatment with ibrutinib plus rituximab. According to the investigators, disease progression was uncommon among patients able to remain on ibrutinib. In those who discontinued treatment with ibrutinib for a reason other than disease progression, the median duration of time from the discontinuation of treatment to disease progression or death was 25 months. Sustained improvement in overall survival was reported with ibrutinib plus rituximab (HR = 0.47; P = .018).
“Additional longer-term follow-up is necessary to provide further insights on late toxicities and complications,” the investigators concluded.
Disclosure: For full disclosures of the study authors, visit ashpublications.org.