Gordon MJ, et al. - In this multicenter, retrospective analysis, the prognostic significance of comorbidities, as assessed by the Cumulative Illness Rating Scale (CIRS), was determined among patients who received treatment with ibrutinib for chronic lymphocytic leukemia (CLL). They found inferior median event-free survival and 2-year overall survival related to a high burden of comorbidities (CIRS score ≥ 7) in these patients. Furthermore, they observed that comorbidities were related to an increased risk of ibrutinib dose reduction and discontinuation of therapy. Overall, a poor prognosis was predicted by comorbidities in this patient population.