Cost-effectiveness of pembrolizumab as second-line therapy for the treatment of locally advanced or metastatic urothelial carcinoma in Sweden

Background: Urothelial carcinoma (UC) is the most common subtype of bladder cancer. The randomized phase 3 KEYNOTE-045 trial showed that pembrolizumab, used as second-line therapy significantly prolonged overall survival with fewer treatment-related adverse events than chemotherapy for advanced UC. Pembro- lizumab has been approved by the European Medicines Agency for the treatment of locally advanced or metastatic UC in adults who have received platinum-contain- ing chemotherapy. Many European countries use cost-effectiveness analysis to inform reimbursement decisions.

Objective: To assess the cost-effectiveness of pembrolizumab as second-line ther- apy for the treatment of advanced UC from a Swedish health care perspective. Design, setting, and participants: We developed a partitioned-survival model to assess the costs and effectiveness of pembrolizumab compared with vinflunine (base case), paclitaxel, or docetaxel monotherapy in patients with advanced UC over a 15-yr time horizon. We obtained Kaplan-Meier estimates for survival end- points, adverse events, and utility data from KEYNOTE-045.

Outcome measurements and statistical analysis: We performed parametric extra- polations to estimate overall and progression-free survival beyond the clinical trial period. Swedish costs and utility weights were used to estimate total costs, quality- adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICERs). We performed deterministic and probabilistic sensitivity analyses to assess the ro- bustness of the model results.

Results and limitations: In the base-case analysis, pembrolizumab resulted in a mean survival gain of 1.66 years (1.38 QALYs) at an incremental cost of s69 852 and an ICER of s50 529/QALY gained versus vinflunine monotherapy. ICERs for other chemotherapies were s81 356/QALY for pembrolizumab versus paclitaxel or doc- etaxel monotherapy, and s71924/QALY for pembrolizumab versus paclitaxel, docetaxel, or vinflunine monotherapy. Long-term follow-up from KEYNOTE-045 and real-world data are needed to validate the extrapolations.