271P - Cost-effectiveness of pembrolizumab as monotherapy or in combination with chemotherapy versus EXTREME regimen for the first-line treatment of recurrent or metastatic head and neck squamous cell carcinoma in Taiwan

Background

To assess the cost-effectiveness of pembrolizumab monotherapy (P) for CPS ≥1 subpopulation and in combination with platinum+5-FU chemotherapy (P+C) for the overall population versus cetuximab+platinum+5-FU chemotherapy (EXTREME regimen: E) for the first line treatment of recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC) in Taiwan.

Methods

A cohort-based partitioned survival model consisting of three health states (progression-free, progressed disease, and death) was developed. Using overall survival and progression free survival data from the P and P+C vs E arms of the KEYNOTE-048 study, the proportion of patients in each health state was estimated by parametric modeling over a 10-year period. Healthcare resource utilization data and costs per unit were sourced from the Taiwan National Healthcare Insurance Research Database, Cancer Registry database based on Taiwan National Health Insurance Administration (NHIA) reimbursement prices.

Results

In the base case analysis, P and P+C resulted in higher costs vs E (P: $1,964,859 vs E: $1,200,788 in the CPS ≥1 population; P+C: $2,301,474 vs E: $1,236,156 in the overall population), and higher quality adjusted life years (QALYs: P:1.22 vs 0.73 in the CPS ≥1 population; P+C: 1.30 vs 0.74 in the overall population). The incremental cost effectiveness ratio (ICER) for P vs E was NT$1,571,914/QALY in the CPS ≥1 population, and NT$1,912,195/QALY for P+C vs E in the overall population, respectively. At a willingness-to-pay threshold of 3 times Taiwan per capita Gross Domestic Product (GDP: NT$2,309,934), the resultant incremental cost/QALY for both P and P+C are considered cost-effective.

Conclusions

Both P and P+C are projected to be cost-effective options compared with E for the first-line treatment of R/M HNSCC patients. These results reflect the assumption of the publicly known pembrolizumab price in Taiwan; the price under managed entry agreement with NHIA may result in lower ICERs further demonstrating greater cost-effectiveness value.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

MSD LLC Taiwan Branch, Taiwan.

Funding

MSD LLC Taiwan Branch, Taiwan.

Disclosure

C.H. Wang: Advisory/Consultancy: Merck Sharp & Dohme (I.A.) LLC Taiwan Branch. All other authors have declared no conflicts of interest.