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.

ABSTRACT

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.