Integrating Real World Evidence in Economic Evaluation of Herpes Zoster Vaccination Among Kidney Transplant Patients in Thailand
Author(s)
Teerapon Dhippayom, PharmD, PhD1, Piyameth Dilokthornsakul, PharmD, PhD2, Jeong-Yeon Cho, PharmD, PhD3, Jackrapong Bruminhent, M.D.4, Chayanis Kositamongkol, MSc, PharmD5, Pochamana Phisalprapa, MSc, PhD, MD5, Nathorn Chaiyakunapruk, PharmD, PhD6.
1Lecturer, Naresuan University, Muang Phitsanulok, Thailand, 2Chiang Mai University, Chiang Mai, Thailand, 3College of Pharmacy, University of Utah, Salt Lake City, UT, USA, 4Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand, 5Mahidol University, Bangkok, Thailand, 6University of Utah, Salt Lake City, UT, USA.
1Lecturer, Naresuan University, Muang Phitsanulok, Thailand, 2Chiang Mai University, Chiang Mai, Thailand, 3College of Pharmacy, University of Utah, Salt Lake City, UT, USA, 4Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand, 5Mahidol University, Bangkok, Thailand, 6University of Utah, Salt Lake City, UT, USA.
OBJECTIVES: Herpes zoster (HZ) poses a considerable health risk to immunocompromised individuals, including kidney transplant recipients. Preventive strategies, such as immunization with the zoster live vaccine (ZVL) or recombinant zoster vaccine (RZV), may help lower this risk. This study aimed to assess the cost-effectiveness of both vaccines in kidney transplant recipients in Thailand.
METHODS: A Markov model was developed from a societal perspective to evaluate three strategies: no vaccination, ZVL, and RZV. The model simulated a hypothetical cohort of kidney transplant recipients starting at age 47, using 1-year cycles over a lifetime horizon. Health states included healthy, HZ, postherpetic neuralgia, and death. Input data were drawn from published literature, real world local epidemiological data, and expert clinical opinion. All costs were based on 2023 Thai-specific data. It projected clinical events, such as HZ and postherpetic neuralgia, and associated costs and quality-adjusted life years (QALYs), with discount rate of 3%. Incremental cost-effectiveness ratios (ICERs) were estimated using Thailand’s willingness-to-pay (WTP) threshold of THB 160,000 per QALY gained. Deterministic and probabilistic sensitivity analyses were conducted, along with the generation of cost-effectiveness acceptability curves (CEACs).
RESULTS: In the base-case analysis, ZVL and RZV had ICERs of THB 30,694 and THB 274,869 per QALY gained, respectively, compared to no vaccination. If the cost of RZV was reduced by 45%, its ICER would fall to THB 153,112 per QALY, below the WTP threshold. At current prices, ZVL had a 99.97% chance of being cost-effective versus 0.03% for RZV. One-way sensitivity analysis identified vaccine efficacy, hospitalization rate, and length of stay as the most influential parameters.
CONCLUSIONS: ZVL is cost-effective under current conditions in Thailand. Although RZV offers greater clinical protection, its high cost limits affordability. A price reduction would improve its cost-effectiveness, supporting its broader use in kidney transplant recipients.
METHODS: A Markov model was developed from a societal perspective to evaluate three strategies: no vaccination, ZVL, and RZV. The model simulated a hypothetical cohort of kidney transplant recipients starting at age 47, using 1-year cycles over a lifetime horizon. Health states included healthy, HZ, postherpetic neuralgia, and death. Input data were drawn from published literature, real world local epidemiological data, and expert clinical opinion. All costs were based on 2023 Thai-specific data. It projected clinical events, such as HZ and postherpetic neuralgia, and associated costs and quality-adjusted life years (QALYs), with discount rate of 3%. Incremental cost-effectiveness ratios (ICERs) were estimated using Thailand’s willingness-to-pay (WTP) threshold of THB 160,000 per QALY gained. Deterministic and probabilistic sensitivity analyses were conducted, along with the generation of cost-effectiveness acceptability curves (CEACs).
RESULTS: In the base-case analysis, ZVL and RZV had ICERs of THB 30,694 and THB 274,869 per QALY gained, respectively, compared to no vaccination. If the cost of RZV was reduced by 45%, its ICER would fall to THB 153,112 per QALY, below the WTP threshold. At current prices, ZVL had a 99.97% chance of being cost-effective versus 0.03% for RZV. One-way sensitivity analysis identified vaccine efficacy, hospitalization rate, and length of stay as the most influential parameters.
CONCLUSIONS: ZVL is cost-effective under current conditions in Thailand. Although RZV offers greater clinical protection, its high cost limits affordability. A price reduction would improve its cost-effectiveness, supporting its broader use in kidney transplant recipients.
Conference/Value in Health Info
2025-09, ISPOR Real-World Evidence Summit 2025, Tokyo, Japan
Value in Health Regional, Volume 49S (September 2025)
Code
RWD125
Topic Subcategory
Health & Insurance Records Systems
Disease
STA: Vaccines