Most Cancer Patients Being Treated Had Adequate COVID-19 Vaccine Response
The benefits of COVID-19 vaccines for cancer patients undergoing treatment have been debated for months. Now, a new Israeli study finds that cancer patients mounted an adequate response, even though they were receiving ongoing therapy, but that their response remained lower than a control group. Find out why the authors strongly recommend vaccination.
PETAH TIVKA, ISRAEL – Until now, the benefits of vaccinating cancer patients undergoing treatment had remained uncertain. While those patients are at high risk of COVID-19, THEIR ability to mount an adequate antibody response to messenger RNA SARS-CoV-2 vaccines was unclear.
A new Israeli study sought to provide an answer to the dilemma. In an article published in JAMA Oncology, Rabin Medical Center researchers determined that, among 102 patients with cancer who were receiving active treatment and compared to 78 healthy controls, 90% of the patients with cancer and 100% of the controls were seropositive after the second messenger RNA BNT162b2 vaccine dose.
Based on findings that patients with cancer who are receiving active treatment and are at higher risk for severe COVID-19 disease respond well to the Pfizer-BioNTech vaccine, the authors emphasize that they should be seriously considered for immunization.
Included in the prospective cohort study were 102 adult patients with solid tumors undergoing active intravenous anticancer treatment and 78 controls who received the second dose of the BNT162b2 vaccine at least 12 days before enrollment. Cancer patients had a median age of 66 and were 57% men The most common tumor type was gastrointestinal in 28%.
Controls were taken from a convenience sample of the patients’ family/caregivers who accompanied the cancer patients to treatment at Davidoff Cancer Center at Beilinson Hospital in Petah Tikva, Israel. They had a median age of 62 and were 68% women. The study was conducted between February 22, 2021, and March 15, 2021.
Researchers drew blood samples from the study participants, determining titers of the IgG antibodies against SARS-CoV-2 spike receptor-binding domain using a commercially available immunoassay. Seropositivity was defined as 50 or greater AU/mL.
Defined as the primary outcome was the rate of seropositivity, while secondary outcomes included comparisons of IgG titers and identifying factors that were associated with seropositivity using univariate/multivariable analyses.
Results indicated that 90% of the patient group was seropositive for SARS-CoV 2 antispike IgG antibodies after the second vaccine dose, although all were seropositive in the control group. Researchers noted that the median IgG titer in the patients with cancer was significantly lower than that in the controls (1931 [IQR, 509-4386] AU/mL vs 7160 [IQR, 3129-11 241] AU/mL; P < .001).
Multivariable analysis suggested that the only variable that was significantly associated with lower IgG titers was treatment with chemotherapy plus immunotherapy (β, −3.5; 95% CI, −5.6 to −1.5).
“Further research into the clinical relevance of lower titers and their durability is required,” the authors conclude. “Nonetheless, the data support vaccinating patients with cancer as a high priority, even during therapy.”
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