Majority of Cancer Patients Respond to COVID-19 Vaccination

A recent study conducted by investigators from the University of Texas Health Science Center at San Antonio, in collaboration with Mays Cancer Center and the University of Geneva, has demonstrated that nearly all cancer patients developed a good immune response to COVID-19 mRNA vaccines 3 to 4 weeks after their second dose.

Results from the study were published in the journal Cancer Cell.

"We observed a significant difference in response when two doses were given," Dimpy P. Shah, a corresponding author on the study said. "At least for patients with cancer, two doses are very important for robust antibody response."

For the study, the team of investigators looked at 140 cancer patients who received either the Pfizer-BioNTech or Moderna COVID-19 vaccines. They assessed short-term humoral immune response by measuring anti-SARS-CoV-2 spike protein (S) immunoglobulin G (IgG) antibody titer levels after 2 doses.

Median follow-up time was 50 days, and the median age of the cohort was 63 years old. Most malignancies were solid tumors (81%)m breast (33%) and urological (19%). There were also 25 (45%) patients with hematological malignancy.

Findings from the study showed that 94% of the patients developed antibodies to COVID-19, with 7 high risk patients not developing any. Those with hematological malignancy had significantly reduced humoral response in comparison to patients with solid tumors.

Additionally, patients with a prior history of an infection with SARS-CoV-2 had an increased anti-S IgG antibody level from pre- to post-vaccination.

“Our study documents that the vast majority of patients with cancer develop positive anti-SARS-CoV-2 spike antibody response at 3 weeks post-completion of mRNA vaccination series, hence administration of both doses is recommended,” the authors wrote. “Our results stress the importance of identifying patients at high risk of non-response post-vaccination, so alternate protection strategy can be developed.”