Real-World Treatment Patterns and Outcomes by Line of Therapy and Race in Patients With Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma Treated in the United States: Results From the Final Analysis of the Prospective, Observational, informCLL Registry

Background informCLL is the largest US-based prospective, observational registry of patients with chronic lymphocytic leukemia (CLL) initiating FDA-approved treatment in the era of targeted therapy. Patients and Methods Patients were enrolled between October 2015 and June 2019. Data were collected for baseline characteristics, treatment patterns, outcomes, and safety. Results In total, 1459 eligible patients were enrolled (first line, n=854; relapsed/refractory, n=605). The most common index treatments were ibrutinib (first line, 45%; relapsed/refractory, 49%) and chemoimmunotherapy (first line, 43%; relapsed/refractory, 20%). With median follow-up of 31.8 and 30.9 months in first-line and relapsed/refractory cohorts, respectively, median time to next treatment (TTNT) in patients who received any index treatment was not reached (NR) and 48.6 months; estimated proportions without next-line therapy at 48 months were 64% and 50%. Median overall survival (OS) was NR for both cohorts; estimated 48-month OS rates were 81% and 64% in first-line and relapsed/refractory cohorts, respectively. In match-adjusted analyses, TTNT was improved with first-line ibrutinib versus chemoimmunotherapy (median NR vs. 56.5 months; hazard ratio, 0.74; 95% CI, 0.56–0.98). Exposure-adjusted rates of AEs leading to discontinuation and serious AEs were lower with ibrutinib versus chemoimmunotherapy. Estimated 36-month OS rates were similar in Black versus White patients who received any index treatment (first line, 87% vs. 83%; relapsed/refractory, 74% vs. 74%) or ibrutinib (first line, 97% vs. 85%; relapsed/refractory, 81% vs. 77%). Conclusion In this prospective, large, real-world CLL registry, first-line ibrutinib was associated with longer TTNT than chemoimmunotherapy, with sustained benefit up to 4 years of follow-up. MicroAbstract informCLL is a large US-based prospective, observational disease registry of patients initiating FDA-approved treatment for CLL/SLL in the era after approval of ibrutinib. In match-adjusted analyses, first-line ibrutinib was associated with longer time to next treatment than chemoimmunotherapy, with sustained benefit up to 4 years of follow-up. Black patients treated with first-line ibrutinib achieved similar outcomes to White patients.