Real-world Clinical Outcomes of First-Line Ibrutinib or Chemoimmunotherapy in Patients with Chronic Lymphocytic Leukemia by Risk Status

INTRODUCTION: Certain genetic features in chronic lymphocytic leukemia (CLL) are associated with inferior outcomes after chemoimmunotherapy (CIT). This retrospective study evaluated treatment patterns and clinical outcomes of patients with CLL, stratified into high-risk and non-high-risk groups, who received first-line ibrutinib or CIT therapy. METHODS: High-risk group included confirmed presence of del(17p), del(11q), unmutated IGHV, TP53 mutations, or complex karyotype. Weighted high-risk ibrutinib and CIT groups were compared for treatment effects using inverse probability of treatment weighting. Hazard ratios [95% CI] (HR) for time to next treatment (TTNT) were analyzed using Kaplan–Meier curves. RESULTS: Bendamustine/rituximab was the most common CIT regimen initiated for high-risk patients. During the available follow-up (median 34–35 months), 74.7% of the weighted high-risk ibrutinib group received only one line of treatment, compared with 47.2% of the weighted high-risk CIT group. The most common second-line treatment was ibrutinib for those in the CIT groups and venetoclax for the ibrutinib groups. The weighted high-risk ibrutinib group had a significantly longer TTNT (median not reached) than the weighted high-risk CIT group (median 34.4 months) and was 54% less likely to start a new treatment (HR 0.5 [0.3–0.6], P < 0.010). Among CIT-treated groups, high-risk patients had significantly shorter median TTNT than non-high-risk patients (P < 0.010). However, within the ibrutinib-treated groups, the median TTNT was similar between high-risk and non-high-risk patients (HR 2.2 [1.0–5.0]; P = 0.060). CONCLUSION: This study found that first-line single-agent ibrutinib therapy was associated with significantly longer TTNT than CIT regimens in real-world patients with high-risk CLL. The results support the use of ibrutinib in high-risk patients. INFOGRAPHIC: [Image: see text] SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12325-021-01991-5.