Ibrutinib Outcomes Not Affected by Genomic Risk Factors

Outcomes after ibrutinib treatment are not affected by unmutated IGHV, del11q, trisomy 12, and complex karyotype (CK) among patients with chronic lymphocytic leukemia/small lymphocytic leukemia (CLL/SLL), according to an abstract presented at the XVII International Workshop on Chronic Lymphocytic Leukemia (iwCLL).¹

Ibrutinib is an effective treatment of CLL/SLL, though del17p is an independent prognostic factor for shorter progression-free survival (PFS) and overall survival (OS). This multivariate analysis of pooled data from 3 phase 3 trials evaluated other the role of other risk factors.

The study evaluated clinical outcomes; multivariate analysis was used to assess covariates including genomic risk factors, age, sex, Eastern Cooperative Oncology Group (ECOG) performance status, cytopenias, lactate dehydrogenase (LDH), bulky disease, and number of prior therapies.

Ibrutinib resulted in prolonged PFS and OS and higher rates of overall response (ORR) and complete response vs all comparators, regardless of genomic factors — unmutated IGHV, del11q, trisomy 12, and CK. Shorter PFS and OS, however, were associated with only 1 prior therapy, age, and elevated LDH. Del11q was associated with a trend of prolonged OS.

Among patients treated with any of the comparators, unmutated IGHV, del11q, and CK were associated with shorter OS and PFS, and del11q and CK were associated with decreased ORR. Decreased PFS was also associated with number of prior therapies, male sex, and bulky disease. Lower OS was associated with male sex, bulky disease ECOG performance status, elevated LDH, and CK.

Adverse event rates were similar among patients who received ibrutinib or a comparator.

According to the investigators, these data suggest that there is no clear association of poor outcomes with unmutated IGHV, del11q, trisomy 12, and CK among patients with CLL/SLL treated with ibrutinib.

Reference

1. Kipps TJ, Mahler M, Fraser G, et al. Outcomes of ibrutinib-treated patients with chronic lymphocytic leukemia/small lymphocytic leukemia (CLL/SLL) with high-risk prognostic factors in an integrated analysis of 3 randomized phase 3 trials. Paper presented at: XVII International Workshop on Chronic Lymphocytic Leukemia; May 12-15, 2017; New York, NY.