A booster COVID-19 dose given to patients with cancer receiving treatment improves the immune response in those already fully vaccinated
A booster COVID-19 vaccine dose to patients with solid tumour cancers undergoing treatment, improves their immune response, according to the results of a study by a team from the University Paris Est Créteil, Paris, France.
Since the beginning of the COVID-19 pandemic, those with cancer have been deemed at high risk and therefore a priority group for access to available vaccines. However, since cancer patients were excluded from the original vaccine efficacy trials, the nature and level of their immunogenic response to vaccination was uncertain. Data from a study among cancer patients on treatment has shown that after a first dose, 29% were seropositive and that this increased to 86% after the second dose, although there appears to be only one study in cancer patients who have received a third vaccine dose and which fortunately demonstrated an enhanced immunogenicity.
For the present study, the French team wanted to evaluate the immunogenicity of two and three doses of a COVID-19 vaccine in cancer patients currently receiving chemotherapy and how this was affected by the type of oncology treatment and the timing of vaccination. Using a prospective, observational design, the team included patients with solid organ active cancer, which they defined as ‘histologic confirmation of solid cancer under treatment within the previous 6 weeks or starting treatment during the next 2 weeks.’ The researchers collected information on the patient’s cancer diagnosis, therapy and cancer stages. All patients had received two doses of BNT162b2 on days 0 and 21 and those who had a prior history of COVID-19 infection or evidence of antibodies before vaccination were excluded. A booster COVID-19 (i.e., third) dose was offered to all of those who had a weak humoral response one month after the second dose, which was defined by an anti-spike protein antibody level below 1000 units.
Findings
In total, 163 patients with a median age of 66 years (53% male) were included in the analysis. The most common form of treatment was chemotherapy (75%), followed by targeted therapy (16%) and immunotherapy (9%).
One month after the first vaccine, only 15% of patients had anti-spike antibody titres > 1000, although one month after the second dose, this proportion increased to 65%. A booster COVID-19 dose was offered to 36 patients whose antibody level remained below 1000 units, one month after the second dose. This resulted in 75% of these patients, achieving antibody levels > 1000, one month after their third dose.
In their analysis, age, sex, cancer type, lymphopenia and use of corticosteroids four or more weeks before vaccination, were not associated with the level of immune response at the time of the second dose or even 28 days after the second dose. However, patients receiving either chemotherapy or targeted therapy had a lower anti-spike level than those given immunotherapy (odds ratio, OR = 5.4, 95% CI 1.5 – 20.2, p = 0.02). Other factors such as the time between vaccination and intravenous chemotherapy administration were also not associated with the intensity of the humoral response.
The authors concluded that a booster COVID-19 dose among those with solid tumours and in receipt of treatment, improved the immune response, highlighting the importance of a third dose in this patient cohort.
Citation
Fenioux C et al. SARS-CoV-2 Antibody Response to 2 or 3 Doses of the BNT162b2 Vaccine in Patients Treated With Anticancer Agents JAMA Oncol 2022
