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.

Time to next treatment in patients with chronic lymphocytic leukemia initiating first-line ibrutinib or acalabrutinib.

Aim: To investigate real-world time to next treatment in patients with chronic lymphocytic leukemia initiating first-line (1L) ibrutinib or acalabrutinib. Materials & methods: US specialty pharmacy electronic medical records (21/11/2018-30/4/2022) were used; patients initiated 1L on/after 21/11/2019 (acalabrutinib approval). Results: Among 710 patients receiving ibrutinib, 5.9% initiated next treatment (mean time to initiation = 9.2 months); among 373 patients receiving acalabrutinib, 7.5% initiated next treatment (mean time to initiation = 5.9 months). Adjusting for baseline characteristics, acalabrutinib-treated patients were 89% more likely to initiate next treatment (hazard ratio = 1.89; p = 0.016). Conclusion: This study addresses a need for real-world comparative effectiveness between 1L ibrutinib and acalabrutinib and shows that next treatment (a clinically meaningful measure for real-world progression) occurred less frequently with 1L ibrutinib.

Ibrutinib and acalabrutinib are oral medications taken once-daily and twice-daily, respectively. They are recommended as initial treatment for chronic lymphocytic leukemia (CLL). The goal of this study was to compare the efficacy of these treatments as initial treatment for CLL. To meet this goal, real-world US specialty pharmacy electronic medical records between 11/21/2018­4/30/2022 were used. Patients treated with ibrutinib or acalabrutinib as initial treatment for CLL were studied. Treatment had to be started on or after the date of acalabrutinib approval for CLL (11/21/2019). Time to next treatment was used to estimate real-world disease progression. It was defined as the time from the initiation of initial treatment with ibrutinib or acalabrutinib to the initiation of a next treatment. Study results showed that patients were observed for a median of up to 1.5 years. Over this period, next treatment was more likely for acalabrutinib (7.5%) compared with ibrutinib (5.9%). After adjusting for differences in patient characteristics, next treatment was 89% more likely with acalabrutinib than ibrutinib. This study addresses a need to compare the effectiveness of initial treatment with ibrutinib and acalabrutinib in the real-world. It helps better contextualize results from clinical trial data and shows that next treatment occurred less frequently with ibrutinib.

Real-World Comparison of First-Line Treatment Adherence Between Single-Agent Ibrutinib and Acalabrutinib in Patients with Chronic Lymphocytic Leukemia.

Purpose: Increased dosing frequency adversely affects treatment adherence and outcomes in chronic diseases; however, such data related to treatment adherence is lacking in chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL). This study compared adherence between patients treated with ibrutinib (once-daily) versus acalabrutinib (twice-daily) as first-line (1L) therapy for CLL/SLL. Patients and Methods: Specialty pharmacy electronic medical records were used to identify adults with CLL/SLL initiating 1L ibrutinib or acalabrutinib between 01/01/2018 and 11/30/2020. Adherence was measured by the proportion of days covered (PDC) and medication possession ratio (MPR) and was compared between cohorts using odds ratios (ORs) obtained from logistic regression models adjusted for baseline characteristics. Results: Between 01/01/2018 and 11/30/2020, 1374 and 140 patients initiated ibrutinib and acalabrutinib, respectively. Based on PDC/MPR ≥80%, patients treated with once-daily ibrutinib were more likely to be adherent than those treated with twice-daily acalabrutinib (OR ranges: PDC: 1.04-1.76; MPR: 1.03-1.58). At 6 months, patients on ibrutinib had a 58-76% higher likelihood of staying adherent compared to patients on acalabrutinib (PDC: 75.9% for ibrutinib vs 63.6% for acalabrutinib, OR: 1.76, P=0.008; MPR: 76.8% vs 66.9%, OR: 1.58, P=0.036) with a similar trend noted for the entire line of treatment (LOT) (PDC: 53.0% vs 41.4%, OR: 1.53, P=0.021; MPR: 58.7% vs 47.1%, OR: 1.50, P=0.027). Conclusion: In this real-world analysis, CLL/SLL patients initiating 1L once-daily ibrutinib had >50% higher treatment adherence than those initiating twice-daily acalabrutinib during their LOT. Given the importance of sustained adherence for disease control in CLL/SLL, dosing frequency may be an important consideration for patients and physicians.