METHODS: Searches were performed until June 2016 using 4 databases: PubMed; Embase; Cochrane Library; and LILACS. The combined WHO, Drummond and CHEERS checklist were used to evaluate the quality of included studies.
RESULTS: Thirty-four studies were included in the review and most of them were conducted in high-income countries. The inclusion of adolescent boys in vaccination program was found to be cost-effective if vaccine price and coverage was low. When coverage for female was above 75%, gender-neutral vaccination was less cost-effective than when targeting only girls aged 9-18 years. Current evidence does not show conclusive proof of greater cost-effectiveness of 9-valent vaccine compared to the older HPV vaccines as the price for 9-valent vaccine was still uncertain. Multicohort immunization strategy was cost-effective in the age range 9-14 years but the upper age limit at which vaccination was no longer cost-effective needs to be further investigated. Key influential parameters identified were duration of vaccine protection, vaccine price, coverage, and discounting rates.
CONCLUSIONS: These findings are expected to support policy-makers in making recommendations for HPV immunization programs on either switching to the 9-valent vaccine or inclusion of adolescent boys' vaccination or extending the age of vaccination.
METHODS: In the first part of the analysis costs attributable to cervical cancer and precancerous lesions were estimated; epidemiologic data were sourced from the WHO GLOBOCAN database and Malaysian national data sources. In the second part, a prevalence-based model was used to estimate the potential annual number of cases of cervical cancer and precancerous lesions that could be prevented and subsequent HPV-related treatment costs averted with the bivalent (HPV 16/18) and the quadrivalent (HPV 16/18/6/11) vaccines, at the population level, at steady state. A vaccine efficacy of 98% was assumed against HPV types included in both vaccines. Effectiveness against other oncogenic HPV types was based on the latest results from each vaccine's respective clinical trials.
RESULTS: In Malaysia there are an estimated 4,696 prevalent cases of cervical cancer annually and 1,372 prevalent cases of precancerous lesions, which are associated with a total direct cost of RM 39.2 million with a further RM 12.4 million in indirect costs owing to lost productivity. At steady state, vaccination with the bivalent vaccine was estimated to prevent 4,199 cervical cancer cases per year versus 3,804 cases for the quadrivalent vaccine. Vaccination with the quadrivalent vaccine was projected to prevent 1,721 cases of genital warts annually, whereas the annual number of cases remained unchanged with the bivalent vaccine. Furthermore, vaccination with the bivalent vaccine was estimated to avert RM 45.4 million in annual HPV-related treatment costs (direct+indirect) compared with RM 42.9 million for the quadrivalent vaccine.
CONCLUSION: This analysis showed that vaccination against HPV 16/18 can reduce the clinical and economic burden of cervical cancer and precancerous lesions in Malaysia. The greatest potential economic benefit was observed using the bivalent vaccine in preference to the quadrivalent vaccine.
METHODS: A Markov cohort model reflecting the natural history of HPV infection accounting for oncogenic and low-risk HPV was adapted for 13 year old Malaysian girls cohort (n = 274,050). Transition probabilities, utilities values, epidemiological and cost data were sourced from published literature and local data. Vaccine effectiveness was based on overall efficacy reported from 3-doses clinical trials, with the assumption that the 2-doses is non-inferior to the 3-doses allowing overall efficacy to be inferred from the 3-doses immunogenicity data. Price parity and life-long protection were assumed. The payer perspective was adopted, with appropriate discounting for costs (3 %) and outcomes (3 %). One way sensitivity analysis was conducted. The sensitivity analysis on cost of vaccine, vaccine coverage and discount rate with a 2-doses protocol was performed.
RESULT: The 3-doses and 2-doses regimes showed same number of Cervical Cancers averted (361 cases); QALYs saved at 7,732,266. However, the lifetime protection under the 2-doses regime, showed a significant cost-savings of RM 36, 722,700 compared to the 3-doses scheme. The MOH Malaysia could vaccinate 137,025 more girls in this country using saving 2-doses regime vaccination programme. The model predicted that 2-doses HPV vaccination schemes can avoid additional 180 Cervical Cancers and 63 deaths compare to 3-doses.
CONCLUSION: A 2-doses HPV vaccination scheme may enable Malaysian women to be protected at a lower cost than that achievable under a 3-doses scheme, while avoiding the same number of Cervical Cancer cases and deaths. Using the saving money with 2-doses, more Cervical Cancers and deaths can be avoided.