There are no therapies that appear to be uniquely effective for patients with mantle cell lymphoma who have pressed on ibrutinib, a study published online ahead of print in the journal Blood has shown.1
Although ibrutinib has unprecedented clinical activity in mantle cell lymphoma, primary and acquired resistance to ibrutinib is common, and the ideal management and outcomes of patients that experience ibrutinib failure remains unclear.
Therefore, researchers sought to conduct a retrospective cohort study of all patients with mantle cell lymphoma that experienced disease progression while receiving ibrutinib therapy from 15 international sites.
For the study, researchers included 114 patients and analyzed their medical records for clinical characteristics, pathological and radiological data, and therapies used prior to and after ibrutinib.
Results showed that median overall survival following ibrutinib therapy was 2.9 months (95% CI: 1.6-4.9). Researchers found that of the 104 evaluable patients, 73 had undergone subsequent treatment an average of about 9 days after stopping ibrutinib. Those patients had a median overall survival of 5.8 months (95% CI: 3.7-10.4).
The study demonstrated no association between subsequent treatment with bendamustine, cytarabine, or lenalidomide and overall survival. Furthermore, investigators observed poor clinical outcomes in the majority of patients with primary or secondary ibrutinib resistance.
“Future trials should focus on understanding the mechanisms of ibrutinib resistance and on treatment following ibrutinib,” the authors conclude.
1. Martin P, Maddocks K, Leonard JP, et al. Post-ibrutinib outcomes in patients with mantle cell lymphoma [published online ahead of print January 13, 2016]. Blood. doi:10.1182/blood-2015-10-673145.