JCVI Advises Third COVID Jab for Severely Immunosuppressed Over-12s

Tim Locke

September 01, 2021

The Joint Committee on Vaccination and Immunisation (JCVI) is advising that severely immunosuppressed people aged 12 and over should have a third vaccine dose as part of their primary COVID-19 vaccination schedule.

The vaccine advisers say this includes patients with leukaemia, advanced HIV, and recent organ transplants.

This group may be less well protected as they may not respond fully to vaccination.

This is separate to an expected general autumn booster programme. The JCVI said it is waiting for more evidence before issuing booster advice.

England's Health Secretary Sajid Javid said the Government has accepted the JCVI’s recommendation.


The third dose advice follows the OCTAVE trial's preliminary data. It found around 40% of people with weakened immune systems had low antibody levels after COVID-19 vaccination.

This group of people is likely to become more severely ill if infected with COVID-19.

JCVI said research is ongoing into third dose efficacy in this group but that an additional vaccine dose is very unlikely to be harmful.

On balance, it said, third doses can be safely offered and may increase protection.

Professor Wei Shen Lim, chair of COVID-19 immunisation for the JCVI, said: "We want people with severely suppressed immune systems to have the best chance of gaining protection from COVID-19 via vaccination. Therefore, we are advising they have a third vaccine dose on top of their initial two doses, as we hope this will reduce their risk of severe outcomes such as hospitalisation and death."

Professor Jonathan Van Tam, England's deputy chief medical officer, said: "I welcome the advice from JCVI to offer a third primary dose to those with severe immunosuppression, at a bespoke interval, advised by their specialist clinician, and guided by the UK’s immunisation handbook, the Green Book.

"We should be doing all we reasonably can to ensure that this group is not disadvantaged and a third primary dose is one step in this direction. We are also working hard to ensure there are other medical interventions that can be used in these groups, including specific treatments like antivirals and monoclonal antibodies."

Which Vaccine, and When?

Adults aged 18 and over will be offered the Moderna or Pfizer/BioNTech vaccines.

Twelve to 17-year-olds will be offered Pfizer/BioNTech.

Specialists will decide on the third dose timing with some flexibility, but this will usually be at least 8 weeks after the second dose.

An example of a flexible approach given by JCVI was to have the third jab before starting chemotherapy rather than during treatment.

People who are less severely immunosuppressed are expected to be covered by a general booster programme.

Severely immunosuppressed people would still likely be offered a booster dose some weeks after their third dose.

'Welcome Guidance'

Commenting via the Science Media Centre, Eleanor Riley, professor of immunology and infectious diseases, University of Edinburgh, said: "This is very welcome guidance and is based on a considerable body of evidence that many people with immunosuppressive diseases or who are receiving immunosuppressive treatments make a detectable but suboptimal antibody response after two doses of the vaccine.

"There is every reason to expect that their immunity can be substantially improved by giving them a third dose.

"It would be wise to actively monitor the response to vaccination in this group of patients so that they can be advised individually of their immune status and adjust their daily activities accordingly."

Kate Collins, chief executive, Teenage Cancer Trust, commented: "We know that young people with cancer continue to be worried about the threat of the virus with some young people continuing to shield and take other precautions despite restrictions lifting.  We welcome the Joint Committee on Vaccination and Immunisation's decision to provide a third vaccine dose for people over 12 who are severely immunosuppressed – including some people with cancer – as this will offer much needed reassurance and additional protection."


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: