How Do Progression-Free Survival and Toxicity Risks Influence Oncologist and Patient Preferences for Novel Agents in Chronic Lymphocytic Leukemia?

Introduction: Treatment for chronic lymphocytic leukemia (CLL) has changed with the approval of novel agents, which have different toxicity profiles. The aim of the current analysis was to determine how incremental changes in efficacy and toxicity profile impact treatment selection among patients with CLL and oncologists. Methods: In this US-based study, oncologists and CLL patients completed an online survey that included a discrete choice experiment (DCE) to quantify preferences for first line (1L) treatment with novel agents. Self-reported data on oncologist and patient characteristics were also collected. In the DCE, respondents selected between hypothetical treatment profiles consisting of 8 attributes with varying levels. The attributes were selected based on the findings of qualitative interviews assessing treatment priorities among oncologists and patients. The attribute levels were abstracted from clinical trials and published literature (Table 1). Hierarchical Bayesian regression models were used to estimate preference weights for each attribute level. The preference weights were used to generate a base case hypothetical treatment profile, against which other hypothetical profiles varying in adverse event (AE) risk and 2-year progression-free survival (PFS) were evaluated to understand which attributes and levels drive treatment selection. The overall mean summed preference weight for the collective set of alternative profiles was then compared with the base case, with higher positive values indicating the more preferred profile. Results: Oncologists (N=151) reported a mean of 16.3±7.0 years in practice (Table 2). Most practiced in a community setting (72%) and in a major metropolitan/urban area (64%). Among patients (N=220), median age was 56.0 years, with a mean disease duration of 2.0±3.1 years at time of study (Table 2). Most patients were in or had completed at least 1L therapy (68%). Figure 1 illustrates the impact of changing various attribute levels on the overall preference of an alternative profile, relative to a base case profile. Decreasing 2-year PFS from 95% to 75% (Profile A) and reducing the risks of atrial fibrillation (A-fib) from 20% to 5% (Profile B) and infection from 30% to 7% (Profile C) had the greatest influence on treatment preferences for oncologists when holding all other attribute levels constant. Oncologists preferred the profile with reduced 2-year PFS and reduced risk of AEs (Profile G) to the base case profile, co