Brentuximab vedotin in relapsed/refractory Hodgkin lymphoma post-autologous stem cell transplant:a cost-effectiveness analysis in Scotland

OBJECTIVE: To evaluate cost-effectiveness of brentuximab vedotin in patients with relapsed/refractory Hodgkin lymphoma who have received autologous stem cell transplantation, from a Scottish healthcare payer perspective. METHODS: A Microsoft Excel-based partitioned survival model comprising three health states (progression-free survival [PFS], post-progression survival, and death) was developed. Relevant comparators were chemotherapy with or without radiotherapy (C/R) and C/R with intent to allogeneic hematopoietic stem cell transplantation (alloSCT). Data were obtained from the pivotal phase II single-arm trial in 102 patients (SG035-0003; NCT00848926), a systematic literature review and clinical expert opinions (where empirical evidence was unavailable). PFS and overall survival for brentuximab vedotin were estimated using 5-year follow-up data from SG035-0003, and extrapolated using event rates observed for comparator treatments from published survival data. Resource use included drug acquisition and administration; alloSCT; treatment of adverse events; and long-term follow-up. Deterministic and probabilistic sensitivity analyses were conducted to evaluate the impact of uncertainty. RESULTS: In the base case, the incremental cost-effectiveness ratio (ICER) for brentuximab vedotin was £38,769 per quality-adjusted life year (QALY) vs C/R, whereas C/R with intent to alloSCT was dominated by brentuximab vedotin. ICERs for brentuximab vedotin generated by the deterministic sensitivity analysis ranged between £32,000-£54,000 per QALY. Including productivity benefits reduced the ICER to £28,881 per QALY. LIMITATIONS: Limitations include lack of comparative data from this single arm study and the heterogeneous population. Inconsistent baseline characteristic reporting across studies prevented complete assessment of heterogeneity and the extent of potential bias in clinical and cost-effectiveness estimates. CONCLUSIONS: Although the base case ICER is above the threshold usually applied in Scotland, it is relatively low compared with other orphan drugs, and lower than the ICER generated using a previous data cut of SG035-0003 that informed a positive recommendation from the Scottish Medicines Consortium, under its decision-making framework for assessment of ultra-orphan medicines.