Cancer patients are less protected against Covid-19 than other people after receiving one dose of the Pfizer-BioNTech vaccine, early finding from the first real-world study investigating the issue suggest, which could leave patients at risk under vaccination strategies like the U.K.’s, where the second dose is delayed in order to vaccinate as many individuals as possible in a shorter time period. The study, which has been published as a pre-print and has not been peer reviewed, looked at the degree of protection one dose of the Pfizer-BioNTech vaccine gave after three weeks in the 205 people recruited.
When testing antibody responses in 205 volunteers (151 of whom had cancer), only 39% with solid cancers and 13% with blood cancer showed a response.
Based on the findings, Dr. Sheeba Irshad, a senior lecturer at King’s College London and a senior author of the study, said she “would recommend an urgent review of the [U.K.’s] vaccine strategy for clinically extremely vulnerable groups.”
Professor Adrian Hayday, also from King’s College London, said the study shows the vaccine “can clearly bring immense benefit to cancer patients too, but in most cases this is only after boosting,” urging patients to be “vaccinated and boosted quickly” with their responses monitored carefully.
CRUCIAL QUOTE
Professor Stephen Evans, Professor of Pharmacoepidemiology, London School of Hygiene & Tropical Medicine, said it is important to note that the response figures quoted in the paper differ from the clinically-based “Vaccine Efficacy” measured in the large trials, warning that the two sets should “not be compared.” He said the data does suggest that vaccines may not protect people with cancer as well as they do for those without, but added that this has “not yet been demonstrated conclusively.”
KEY BACKGROUND
The findings, though preliminary, give reason to reflect on vaccination strategies that delay the second dose in an effort to boost immunity in as many people as possible. The U.K. is notable in this regard, spacing shots out by 12 weeks against manufacturer’s guidelines. The approach was reluctantly endorsed by the World Health Organization, though it stopped short of the British approach with only a six week delay between doses recommended in “exceptional circumstances.” Findings from real-world studies have largely vindicated the approach, with the various vaccines offering “high level of protection” and slowed transmission after just one dose.
