The UK government is considering acting on advice that would reduce the number of HPV vaccines given to young people from two doses to one. The vaccine, currently offered to girls and boys aged 11–13, is administered to help prevent cancers caused by the human papillomavirus (HPV) – including the cervical cancer, the ‘silent killer’. A second dose is usually given about a month after the first.
But now the Joint Committee on Vaccination and Immunisation (Department of Health and Social Care, 2022) believes that there is evidence to show that one dose is enough to offer protection. The announcement followed a 6-week consultation earlier this year.
In its response to interim advice on the administration of the vaccine, the JCVI noted that ‘the overall concern cited by stakeholders is that it may be too early to make the decision to change to a one-dose schedule and it may be risky to do this, as the evidence is incomplete with no evidence on duration of protection beyond 12 years. The view of stakeholders is that it would be better to wait until the one-dose trials are complete’.
However, it said, the JCVI had made a ‘detailed review’ of the available evidence – including from research conducted in communities overseas – and considered that the evidence was now ‘very strong that one dose provides similar protection to that induced by 2 doses’.
It went on: ‘The committee considers that it would not be likely that the picture would change in the next few years. This is because there is already trial and non-trial evidence that initial vaccine efficacy from one dose is very high and likely comparable to that from two doses.’
‘In addition, the long duration of protection already seen is associated with a level of antibody that is steady and it is not biologically plausible that the antibody would suddenly fall in the next few years after being sustained for more than 10 years. The one-dose antibody level is associated with high efficacy against persistent infection of HPV vaccine types.’
The JCVI's report said that the single-dose schedule ‘breaks the dogma that a prime and a booster is required for this type of vaccine’. It said that the papillomavirus had not evolved to evade vaccinations.
Dr Vanessa Saliba, a member of the JCVI, said that the proof for one dose was compelling. ‘The advice has now been published and we will make sure that we work with the NHS and health partners to support the rollout of any changes to the programme.’
In addition to the routine adolescent programme, there is a separate HPV vaccination programme for gay and bisexual men and other men who have sex with men aged up to 45 years, which is delivered through sexual health clinics.
If approved, the new single-dose regimen will apply to the vaccination of both girls and boys – though there is limited research into the effects of reducing the dosage in young males. The JCVI's view, the report said, is that ‘there is currently no reason to doubt that protection will be the same in boys as it is for girls’.
However, incidence of cervical and other cancers associated with HPV would be kept under review, with a possibility of the reintroduction of two doses if it is shown over a period of years that immunity is waning. There will also be increased opportunities for administering the one-dose vaccine in schools to ensure that no child is missed.
There are more than 100 different types of HPV and infections do not usually cause any symptoms – although some types can cause warts. These may appear on the hands, feet, genitals or inside the mouth.
The virus is very contagious and is spread by close skin-to-skin contact. Most people will not be aware that they are infected, and their bodies will eradicate the virus without treatment.
‘The JCVI's report said that the single-dose schedule “breaks the dogma that a prime and a booster is required for this type of vaccine". It said that the papillomavirus had not evolved to evade vaccinations.’
‘Depending on when the UK government makes its decision, the earliest date for implementation of the single-dose vaccine to adolescents would be during the 2023–2024 academic year.’
High-risk types of HPV, on the other hand, can cause abnormal tissue growth which can lead to cancers. The vaccine protects against the types of HPV that cause nearly all cases of cervical cancer, most anal cancers, and some genital and head and neck cancers.
The JCVI decision coincided with similar advice from the World Health Organization (2022), whose Strategic Advisory Group of Experts on Immunization (SAGE) had also been evaluating the evidence emerging over past years that single-dose schedules provided comparable efficacy to the two or three-dose schedules.
The WHO hailed the outcomes as a ‘game changer for the prevention of the disease’ and would allow more doses of the jab reaching more girls, especially in poorer countries where women were found to be more prone to contracting cervical cancer.
WHO Assistant Director-General Dr Princess Nothemba (Nono) Simelela said: ‘I firmly believe the elimination of cervical cancer is possible. This single-dose recommendation has the potential to take us faster to our goal of having 90 per cent of girls vaccinated by the age of 15 by 2030.’
Cervical cancer is the fourth most common cancer in women around the world, killing more than 300 000 each year.
GP, Dr Jacqui Bradley, said the outcomes of several studies into the dosage regimen should give parents confidence that the appropriate decision was being taken.
‘We are constantly learning about the efficacy of vaccines and the HPV has proved to be one of the most successful of recent years in cutting out illness and death,’ she said. ‘It has been challenging at times, with some schools unwilling to cooperate for religious reasons, but the messages are now getting through.
‘Families should speak to their GP if they have any concerns. My main concern would be that the changes were being made because of cost, but this appears not to be the case.’
Depending on when the UK government makes its decision, the earliest date for implementation of the single-dose vaccine to adolescents would be during the 2023–2024 academic year. A final decision will be taken jointly by the United Kingdom Health Security Agency, NHS England and the Department for Health and Social care, and the devolved administrations.