COVID-19 booster vaccine doses strengthen immunity in blood cancer patients
Southampton researchers have shown repeated COVID-19 vaccinations help protect people with lymphoma against the virus.
Four doses increased immunity the most. The finding comes from the two-year PROSECO study.
Southampton recruited the most patients to the national study.
The new insight is important because blood cancer patients have weaker immune systems.
This is either as a result of cancer, or from cancer treatments. This leaves them more vulnerable to COVID-19 than other people, and raises questions over how well they respond to vaccination.
The study’s latest findings are published in the medical journal The Lancet.
Southampton a leading site
Dr Sean Lim, Associate Professor at the University of Southampton’s Centre for Cancer Immunology, led the PROSECO study.
Southampton General Hospital, one of nine sites, recruited over 100 patients with lymphoma to the study. This was around a fifth of the total number recruited throughout 2021 and 2022. The study was supported by the NIHR Southampton Clinical Research Facility.
Blood samples were taken from the patients before their first vaccination and then at several intervals after their first, second, third and fourth doses.
The researchers evaluated the strength of the cancer patients’ immune response to the vaccine. They assessed how effective this might be at protecting them from COVID. The team examined the link between antibody levels and T-cell responses with COVID-19 infection and symptom severity.
Four doses best
The results suggest a fourth vaccine dose generates more effective antibodies than those observed after a third dose. This suggests with increasing vaccine doses, higher quality antibodies are produced. This results in fewer antibodies being needed to fight the infection.
They also looked at nine participants admitted to hospital with COVID-19. Over half (56%) had absent T-cell responses, compared to only a fifth (16%) of 45 participants infected but not hospitalised.
Dr Lim comments: “While the threat from COVID-19 is greatly reduced for most of us, for those with weakened immune systems, such as blood cancer patients, the risk remains very real. Our findings support the need for immunocompromised patients to continue booster vaccinations to maintain a high level of protection.
“The PROSECO study also shows that antibody testing, and potentially T-cell testing, can help establish the risk of COVID-19 for patients with lymphoma at an individual level.”
The PROSECO study is funded by the Blood Cancer UK Vaccine Research Collaborative. It involves researchers from Southampton, London, Oxford, Nottingham, Leicester, Newcastle, Portsmouth, Hereford, Bedford and Norwich.
Identifying those still at risk
A new study called STRAVINSKY, co-led by the University of Southampton, is due to start recruiting within in the next month or so. It will investigate whether antibody testing can identify vulnerable patients who remain at greatest risk of severe COVID-19 infection after vaccination.
The STRAVINSKY study is funded by the National Institute for Health and Care Research (NIHR). It is led by researchers from Southampton, Birmingham, Oxford, Imperial College and Queen Mary in London.