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A press release from the UK Health Security Agency (UKHSA) states that teenagers and eligible GBMSM under the age of 25 will only require a single HPV jab from September, following updated advice from JCVI.
Prof Mark Jit, Professor of Vaccine Epidemiology, London School of Hygiene & Tropical Medicine, said:
“HPV vaccines are even more effective than we originally anticipated when they were first developed, and are already reducing the number of cancers in the UK and around the world. Over the last few years, trials and other studies in several countries have shown that a single dose of the HPV vaccine will also provide that type of robust protection, and the antibodies against HPV that are generated after one dose remain stable over the long-term. Mathematical modelling studies also indicate that a one-dose programme will continue to deliver substantial public health benefits. The move to a one-dose programme in the UK reflects this evidence, and is consistent with the conclusions reached by the World Health Organization, as well as similar moves by several other countries including Australia and Ireland. As JCVI noted, the resources freed up from the move to one dose can be re-directed to strengthening the programme, improving our already high vaccine coverage levels and ensuring that anyone who misses their dose still has other opportunities to receive it.”
Prof Margaret Stanley, Emeritus Professor of Epithelial Biology and Research Visitor in the Department of Pathology, University of Cambridge, said:
“More than 90% of cervical cancer cases irrespective of geographical location are caused by infection with an oncogenic (cancer causing) human papillomavirus. The current HPV vaccines prevent infection with the most common of these HPVs and one vaccine Gardasil9 prevents infection with 7 oncogenic HPVs giving greater than 90% protection against cervical cancer. Because the vaccine prevents infection herd immunity is very high in vaccinated populations. To date the vaccines are given as 2 shots to 12-13 year old boys and girls before they are likely to be exposed or infected with the virus but several studies now show that only 1 dose of the HPV vaccinee is needed to prevent infection. Two studies have now extended over more than 10 years – a small study from Costa Rica now out to 16 years and a large study from India with more than 17000 subjects followed over 10 plus years. In both these prevention of persistent virus infection was as good with 1 dose as 2 or 3 over a 10 year period. A randomised control trial in Kenya has recently reported. In this trial girls 16-23 were vaccinated with either an HPV vaccine or a meningococcal vaccine and followed for 3 years for infection with the vaccine HPV types. Vaccine efficacy against HPV 16 and 18 was 97% and 95.5% against the 7 oncogenic types in the 9 valent vaccine. These results are compelling since the level of infection with these HPV types in Kenya is very high but 1 dose has prevented infection. The antibody levels are lower with 1 compared to 2 doses but stay steady and stable for greater than 11 years. This evidence together with modelling studies is the basis for the WHO and JCVI recommendations.
“There are no studies in HIV infected and other immunosuppressed populations so no changes have been recommended for these groups.
“One dose has been as good as 2 or 3 in preventing infection for at least 10 years, antibody levels stay stable for more than 10 years. These vaccines work but only if they are given to enough people vaccine uptake is crucial and we should focus on that.”
Declared interests
Prof Mark Jit: “I am a member of the Single Dose HPV Vaccine Consortium, which is funded by the Bill & Melinda Gates Foundation to synthesize existing evidence and evaluate new data around single-dose HPV vaccination (https://www.path.org/programs/center-for-vaccine-innovation-and-access/single-dose-hpv-vaccine-evaluation-consortium/).”
Prof Margaret Stanley: “I was on the HPV Advisory group for SAGE as well as the expert advisor for JCVI on this issue.”