The RCGP has urged cancer patients to ‘remain calm’ and not ‘immediately contact their surgery’ for a second dose appointment, after a study suggested a single dose of the Pfizer/BioNTech vaccine may still leave them vulnerable to Covid-19.
The college called for patients and GPs to be patient while it seeks ‘urgent guidance’ about the implications of the study from the Joint Committee on Vaccination and Immunisation (JCVI).
The Francis Crick Institute and King’s College London study – which has not yet been peer reviewed – found that only half (51%) of cancer patients who had received the first dose of the Pfizer/BioNTech Covid-19 vaccine had developed antibodies at five weeks.
The authors suggested that the current 12-week gap between the first and second doses of the vaccine could leave the patients vulnerable to Covid-19 and called for an urgent review of the vaccine strategy for those in the clinically extremely vulnerable group.
Professor Martin Marshall, RCGP chair, said: ‘This is disappointing, especially when GPs are working hard to deliver the vaccine in order to protect as many people as possible as quickly as possible – but it’s also a salutary warning that there is still a way to go before we are safely out of this crisis.
‘We understand that this is a difficult situation and that patients will be very worried, but we urge people to remain calm.’
He added: ‘GPs and their teams themselves will only just be finding out about this and will therefore not be in a position to answer patients’ concerns or provide quick solutions.’
Data from the study showed that an antibody response was found in 39% and 13% of solid and blood cancer patients respectively three weeks after their first dose, compared to 97% of patients without cancer.
The immune response among solid cancer patients did however rise to 95% when a second dose was administered three weeks after the first, the study found.
The preprint, published on medRxiv yesterday (11 March), said researchers had enrolled 151 cancer patients and 54 healthy controls in the study, with 47 of them receiving two doses of the Pfizer vaccine, 21 days apart.
Dr Sheeba Irshad, a Cancer Research UK clinical research fellow from King’s College London, said: ‘Based on our findings, we would recommend an urgent review of the vaccine strategy for clinically extremely vulnerable groups. Until then, it is important that cancer patients continue to observe all public health measures in place such as social distancing and shielding when attending hospitals, even after vaccination.’