ASH 2019: Updated Trial Results With Ibrutinib and Rituximab in CLL
Posted: Monday, December 16, 2019
Progression-free survival is improved in younger patients with previously untreated chronic lymphocytic leukemia (CLL) when treated with ibrutinib and rituximab rather than fludarabine, cyclophosphamide, and rituximab (FCR). Updated results from the E1912 trial were presented at the 2019 American Society of Hematology (ASH) Annual Meeting & Exposition in Orlando, Florida, by Tait D. Shanafelt, MD, of Stanford University, and colleagues.
This phase III trial enrolled patients with treatment-naive CLL aged 70 or younger. Patients were randomly assigned to receive either ibrutinib and rituximab or six courses of intravenous FCR. After a median follow-up of 45 months, 73% of patients receiving the ibrutinib combination remained on the drug, and the median time on treatment was 43 months.
At the time of current follow-up, there were 110 progression-free survival events, with the hazard ratio favoring ibrutinib and rituximab rather than FCR (hazard ratio = 0.39). A subgroup analysis suggests that ibrutinib was more effective in patients with a nonmutated immunoglobulin heavy chain variable region (hazard ratio = 0.28); however, patients with mutated immunoglobulin heavy chain regions did not show significant differences in survival.
A total of 95 patients discontinued ibrutinib due to disease progression or death (24%), adverse events or complications (51%), and withdrawal of consent or other reasons (25%). The Cumulative Illness Rating Scale predicted the discontinuation of ibrutinib for a reason other than disease progression or death (hazard ratio = 1.13 per unit increase). The median time on ibrutinib for patients who discontinued the drug for reasons other than disease progression and death was 15.1 months, whereas the median time from drug discontinuation to disease progression or death was 23 months.
Disclosure: For full disclosures of the study authors, visit ash.confex.com.