Abstract
Objective: To evaluate the cost-effectiveness of brentuximab vedotin in patients with R/R sALCL from a UK NHS perspective. Methods: A partitioned survival model used clinical outcomes for brentuximab vedotin from the pivotal phase-2 single-arm trial of brentuximab vedotin in 58 patients with R/R sALCL (SG035-0004; NCT00866047), over a lifetime (30-year) time horizon. Comparison with conventional chemotherapy was based on data from the Canadian British Columbia Cancer Agency registry from 40 patients starting salvage chemotherapy after front-line treatment between 1980 and 2012. Survival was extrapolated using parametric distributions, with brentuximab vedotin risk after the trial period assumed equal to conventional chemotherapy. Other modelling assumptions were based on a systematic literature review and clinical expert opinion. Results: Based on statistical extrapolation, brentuximab vedotin was associated with 3.1 years longer duration in the progression-free survival health state and an overall survival improvement of 5.4 years, prior to discounting. In addition, brentuximab vedotin was associated with 2.5 quality-adjusted life years (QALYs) gained at a total incremental cost of £88 556, resulting in an incremental cost-effectiveness ratio (ICER) of approximately £35 400. Sensitivity analyses of alternative model assumptions provided ICERs ranging from approximately £28 100 to £61 900. Comparing only first-line salvage patients reduced the ICER to £26 800 per QALY gained. Conversely, considering only patients with Eastern Corporative Oncology Group performance status of 0 or 1 increased the ICER to approximately £38 200. At a willingness-to-pay threshold of £50 000, the estimated probability that brentuximab vedotin is cost-effective compared with conventional chemotherapy was 86.5%. Conclusion: Compared to conventional chemotherapy, and considering the full survival period, brentuximab vedotin may provide a valuable treatment choice for patients with R/R sALCL, a population with limited therapeutic options.