Sunday, 1st October 2023

WHO endorses one-dose HPV vaccine for solid protection against cervical cancer

By Chukwuma Muanya
14 April 2022   |   2:57 am
The World Health Organisation (WHO) Strategic Advisory Group of Experts on Immunisation has concluded that a single-dose Human Papillomavirus (HPV) vaccine delivers solid protection

Cervical Cancer

The World Health Organisation (WHO) Strategic Advisory Group of Experts on Immunisation has concluded that a single-dose Human Papillomavirus (HPV) vaccine delivers solid protection against HPV, the virus that causes cervical cancer that is comparable to two-dose schedules. This could be a game-changer for the prevention of the disease; seeing more doses of the life-saving jab reach more girls.

SAGE is charged with advising WHO on overall global policies and strategies, ranging from vaccines and technology, research and development, to delivery of immunisation and its linkages with other health interventions.

SAGE, at the April 4-7 convening, evaluated the evidence that has been emerging over past years that single-dose schedules provide comparable efficacy to the two or three-dose regimens. Often referred to as the ‘silent killer’ and almost entirely preventable, cervical cancer is a disease of inequity of access; the new SAGE recommendation is underpinned by concerns over the slow introduction of the HPV vaccine into immunization programmes and overall low population coverage, especially in poorer countries.

More than 95 per cent of cervical cancer is caused by sexually transmitted HPV, which is the fourth most common type of cancer in women globally with 90 per cent of these women living in low- and middle-income countries.

SAGE Chair, Dr. Alejandro Cravioto, said: “The HPV vaccine is highly effective for the prevention of HPV serotypes 16 and 18, which cause 70 per cent of cervical cancer.

“SAGE urges all countries to introduce HPV vaccines and prioritise multi-age cohort catch up of missed and older cohorts of girls. These recommendations will enable more girls and women to be vaccinated and thus preventing them from having cervical cancer and all its consequences over the course of their lifetimes.”

SAGE recommends updating dose schedules for HPV as follows: one or two-dose schedule for the primary target of girls aged nine-14; one or two-dose schedule for young women aged 15-20; and two doses with a six-month interval for women older than 21.

Immuno-compromised individuals, including those with Human Immuno-deficiency Virus (HIV), should receive three doses if feasible, and if not at least two doses. There is limited evidence regarding the efficacy of a single dose in this group.

WHO’s recommendations will be updated following further consultation across stakeholders.

Assistant Director-General of WHO, Dr. Princess Nothemba (Nono) Simelela, said: “I firmly believe the elimination of cervical cancer is possible. In 2020 the Cervical Cancer Elimination Initiative was launched to address several challenges including the inequity in vaccine access. 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.”

Globally, the uptake of the life-saving vaccine has been slow, and coverage in countries much lower than the 90 per cent target. Consequently, in 2020 global coverage with two doses was only 13 per cent. Several factors have influenced the slow uptake and low coverage of HPV vaccines including supply challenges, as well as the programmatic challenges and costs related to delivering a two regimens to older girls who are not typically part of childhood vaccination programmes. Added to this has been the relatively high cost of HPV vaccines, particularly for middle-income countries.

Simelela added: “We need political commitment complemented with equitable pathways for the accessibility of the HPV vaccine. Failure to do so is an injustice to the generation of girls and young women who may be at risk of cervical cancer.”

The option for a single dose of the vaccine is less costly, less resource-intensive and easier to administer. It facilitates implementing catch-up campaigns for multiple age groups, reduces the challenges linked to tracing girls for their second dose and allows for financial and human resources to be redirected to other health priorities.”

Other meeting highlights of the April 4-7 Strategic Advisory Group of Experts on Immunization (SAGE) convening include COVID-19 vaccines; Hepatitis A; Poliovirus vaccine; and Immunisation Agenda 2030 (IA2030).

SAGE evaluated the data on the CanSino Bio (Ad5-nCOV-S) vaccine. The outcomes of this discussion will be made available subject to WHO European Union Listing (EUL) being granted.

SAGE also discussed the evidence on the immunity from infection and in combination with vaccination (“hybrid immunity”) and requested a technical paper to be produced by WHO.

SAGE recommends that programmes can use either one or two-dose schedules of inactivated hepatitis A vaccine.

SAGE endorsed calls for an intensified planning effort for “Oral Polio Vaccine (OPV) Cessation” to anticipate the post-certification of wild-type poliovirus eradication time, and the eventual global end of the use of all live, attenuated oral polio vaccines as part of routine immunization programs.

SAGE endorsed IA2030’s report “Guiding Principles for recovering, building resiliency, and strengthening of immunisation in 2022 and beyond”

Meanwhile, in 2020 the World Health Assembly adopted a new global strategy to eliminate cervical cancer as a public health problem. To achieve the vision, the global strategy sets targets that must be met by 2030 for countries to be on the path toward cervical cancer elimination: 90 per cent of girls are fully vaccinated with HPV vaccine by age 15 years; 70 per cent of women are screened with a high-performance test by 35 years of age and again by 45 years of age, and 90 per cent of women identified with the cervical disease receive treatment (90 per cent of women with pre-cancer treated, and 90 per cent of women with invasive cancer managed).

In its next meeting, the Expert Group will look at the barriers and discuss solutions to design resource-stratified service platforms with the capacity to deliver high-quality cervical cancer ‘screen and treat’ systems, and strategies to implement them at a speed and level of coverage that rapidly reduces cervical cancer incidence, tailored to the local context.

The group of experts will also consider recommendations to WHO on how the organisation can further support Member States in the implementation of the interventions recommended in the global strategy.