Clinical and economic impact of school‐based nonavalent human papillomavirus vaccine on women in Singapore: a transmission dynamic mathematical model analysis

OBJECTIVE: To examine the epidemiological and economic impact of a nine-valent (nonavalent) human papillomavirus (HPV) 6/11/16/18/31/33/45/52/58 vaccine programme for young teenagers in Singapore. DESIGN: Mathematical modelling. SETTING: Pharmaco-economic simulation projection. POPULATION: Singapore demography. METHODS: Clinical, epidemiological and financial data from Singapore were used in a validated HPV transmission dynamic mathematical model to analyse the impact of nonavalent HPV vaccination over quadrivalent and bivalent vaccines in a school-based 2-dose vaccination for 11- to 12-year-old girls in the country. The model assumed routine cytology screening in the current rate (50%) and vaccine coverage rate of 80%. MAIN OUTCOME MEASURES: Changes over a 100-year time period in the incidence and mortality rates of cervical cancer, case load of genital warts, and incremental cost-effectiveness ratio (ICER). RESULTS: Compared with bivalent and quadrivalent HPV vaccination programmes, nonavalent HPV universal vaccination resulted in an additional reduction of HPV31/33/45/52/58 related CIN1 of 40.5%, CIN 2/3 of 35.4%, cervical cancer of 23.5%, and cervical cancer mortality of 20.2%. Compared with bivalent HPV vaccination, there was an additional reduction in HPV-6/11 related CIN1 of 75.7%, and genital warts of 78.9% in women and 73.4% in men. Over the 100 years, after applying a discount of 3%, disease management cost will be reduced by 32.5% (versus bivalent) and 7.5% (versus quadrivalent). The incremental cost-effectiveness ratio (ICER) per quality-adjusted life-year gained was SGD 929 compared with bivalent vaccination and SGD 9864 compared with quadrivalent vaccination. CONCLUSION: Universal two-dose nonavalent HPV vaccination for 11- to 12-year-old adolescent women is very cost-effective in Singapore. TWEETABLE ABSTRACT: Nonavalent HPV vaccination of 11- to 12-year-old girls is cost-effective in Singapore.