Human papillomavirus (HPV) infection is associated with cervical cancer and with other anogenital and head and neck cancers and anogenital warts. Two HPV vaccines are currently licensed in the South Korea, the bivalent HPV vaccine which targets HPV types 16 and 18 (which are associated with 70–80% of cervical cancers), and the quadrivalent HPV vaccine, which also targets HPV types 6 and 11 (associated with 85–95% of cases of anogenital warts) in addition to HPV type 16 and 18. WHO recommended that routine HPV vaccination should be included in national immunization program. In Korea, public vaccination program are not implemented yet and there have been no cost-effectiveness analyses for quadrivalent HPV vaccine compared with bivalent HPV vaccine.
To examine cost effectiveness of quadrivalent human papillomavirus (HPV) vaccine compared with bivalent vaccine and no vaccination (screening only) in Korea.
We adapted previously published dynamic transmission mode and calibrated it to the Korean context simulating the natural history of cervical cancer and genital warts in Korea. We assumed that the vaccination program would be combined with current cervical cancer screening in Korean. Vaccination strategy is HPV vaccination of girls at the age of 12, who receive two doses of HPV vaccine (80% coverage). We assumed that the relative effectiveness of two dose of vaccine was the same as three doses and the duration of protection of HPV vaccination to be life-long for both vaccines. We did not consider other HPV type except HPV type 6, 11, 16 and 18 in this model. The costs of vaccinations were assumed based on 70% of estimated market prices; the cost of quadrivalent vaccination was assumed as KRW 108,000 and the cost of bivalent vaccination was assumed as KRW 81,000.
In the base case analysis, the incremental cost-effectiveness ratio (ICER) of the quadrivalent and bivalent vaccines compared with current screening only strategy were KRW 13,727,353 ($ 11,439, $1 = 1,200KRW) and KRW 23,999,474 ($20,000) per QALY-gained, respectively. The ICER of quadrivalent vaccine versus bivalent vaccine was KRW 4,677,273 ($ 3,898).
Vaccinating 12- year- old girls against HPV with the quadrivalent HPV vaccine is estimated to be cost-effective over the bivalent vaccines in the Korean setting considering the criteria for threshold of ICER in Korea ranges from KRW 20,000,000 to 30,000,000 ($16,000 to $25,000). In addition, ICER of the quadirivalent HPV vaccine was lower than ICER of the bivalent HPV Vaccine when compared with current screening only strategy.