Three-Variable CLL Comorbidity Index Predicts Survival, Tolerance of Ibrutinib in Patients with CLL

The Chronic Lymphocytic Leukemia (CLL) Comorbidity Index (CLL-CI), which examines endocrine, vascular, and upper-gastrointestinal conditions, reliably predicted survival and tolerance of ibrutinib therapy in patients with CLL, according to a study presented at the 62nd American Society of Hematology Annual Meeting & Exposition.

The researchers, led by Max J. Gordon, MD, of the MD Anderson Cancer Center in Houston, conducted a retrospective review of 339 patients with CLL who were treated with ibrutinib at nine academic centers between 2014 and 2019.

At the time of starting ibrutinib, clinicians assessed vascular, endocrine, and upper-gastrointestinal organ systems. Each system received a score ranging from zero to three in order of increasing dysfunction severity, subsequently generating the CLL-CI score. A score of two or greater is considered high-risk.

The median age of the patient population was 68 years. Approximately 71% of the patients were treated with ibrutinib in the relapsed/refractory setting. The median overall follow-up period was 23 months (range, 1-71 months).

The majority of patients (60%) had a high-risk CLL-CI score. High CLL-CI score was associated with shortened event-free survival (hazard ratio [HR], 1.65; P=0.014) in a multivariate analysis adjusted for age, del(17p), and relapsed disease.

Discontinuation of ibrutinib due to adverse events was more frequent in patients with a high CLL-CI score (25% vs. 14%; P=0.014). Additionally, a greater proportion of patients with a high CLL-CI score died because of disease progression (28% vs. 8%; P<0.001).

The researchers also found more rates of cardiovascular disease in the group of patients with a CLL-CI score of two or greater (37% vs. 16%; P<0.001) as well as higher rates of hypertension with high CLL-CI (63% vs. 35%; P<0.001).

“This result combined with the simplicity of scoring the CLL-CI makes it an attractive tool for clinical practice,” the researchers wrote. “CLL-CI needs to be explored prospectively in patients treated with ibrutinib and other targeted therapies.”