New study of nearly 185,000 patients recommends boosting immunity against COVID-19 in people with cancer

Researchers from the Institut de Investigació en Atenció Primaria Jordi Gol (IDIAPJGol) and the Barcelona Institute for Global Health (ISGlobal) have led a study on the effectiveness of vaccines against COVID-19 among cancer patients in Catalonia. The research was published in the journal Nature CommunicationsRecommends administering additional doses of vaccine among this at-risk population.

Cancer patients are at higher risk of death from COVID-19, particularly those with lung cancer, blood-related malignancies or who are undergoing systemic treatment such as chemotherapy.

The participation of patients with active cancer in clinical trials conducted to test the effectiveness of vaccines against COVID-19 has been very limited, so it has not been possible to precisely know the effectiveness of vaccination against the SARS-CoV-2 virus among this risk group. However, prospective data from several studies suggest that cancer patients may develop fewer protective antibodies to the COVID-19 virus than the general population, especially after receiving a single dose of the vaccine.

Real World Data

The study confirms these results, based on the analysis of huge data obtained from clinical registries. It is the most comprehensive work to date on this issue and the first of its kind with information from real-world data, providing a more realistic view of how vaccines are working in everyday clinical practice among people with cancer.

The researchers analysed data from 184,744 patients with neoplasia included in the Information System for the Development of Research in Primary Care (SIDIAP), a database that covers people treated at the first level of care in Catalonia. Half of the individuals included in the study (92,372) had received at least the first full vaccination (two doses of the vaccine) and the other half (92,372) were not vaccinated at work.

The researchers compared data on mortality and serious complications from COVID-19 in the vaccinated group after receiving the first and second doses of the vaccine with data from the unvaccinated group. Next, the researchers compared the outcomes of members of the experimental group after receiving a booster dose of the vaccine (which included 54,267 patients) with an equivalent sample of people in the control group who received only the first two vaccines.

The results of the study show that cancer patients who are not vaccinated against COVID-19 have twice the rate of mortality and serious complications compared to those who have taken the first full dose. However, this difference is less than the data seen between the general population vaccinated against SARS-CoV-2 and the non-vaccinated population.

“Our results clearly demonstrate that vaccination against COVID-19 significantly reduces mortality and severe complications in cancer patients, especially in those who received a booster dose,” said ISGlobal researcher Otavio Ranzani, who supervised the study together with Talita Duarte-Salles of IDIAPJGOL.

For his part, the researcher pointed out that “this work provides essential information to understand the impact of vaccination against COVID-19 on cancer patients, and helps to design public health policies that protect this vulnerable population.”