Patients with cancer achieve response to messenger RNA COVID-19 vaccine
A high percentage of patients undergoing treatment for cancer achieved a sufficient antibody response to the BNT162b2 messenger RNA COVID-19 vaccine, according to study results published in JAMA Oncology.
“Patients and health care providers had been extremely preoccupied wondering if patients with active cancer could develop antibodies [after] COVID-19 vaccination,” Salomon M. Stemmer, MD, professor at the Institute of Oncology of Rabin Medical Center in Israel, told Healio. “In Israel, patients with cancer were highly prioritized and so it was obvious to conduct this study. Every patient was contacted after we had the results of the study, and they were all satisfied with the results.”
Stemmer and colleagues compared rates of antispike antibody response to the BNT162b2 (Pfizer/BioNTech) vaccine among 102 adults (median age, 66 years; 57% men) with solid tumor cancers undergoing treatment between Feb. 22 and March 15, 2021, at Davidoff Cancer Center at Beilinson Hospital in Israel and 78 healthy controls (median age, 62 years; 68% women) consisting of family members and caregivers who escorted them to treatment.
Tumor types included gastrointestinal (28%), lung (25%), breast (18%), brain (9%) and genitourinary (8%).
All participants received the second dose of the vaccine at least 12 days before study enrollment.
Researchers collected plasma samples from study participants and determined titers of immunoglobulin G antibodies against COVID-19 spike receptor-binding domain using a commercially available immunoassay. They defined seropositivity as 50 AU/mL or greater.
The rates of seropositivity served as the primary outcome. Secondary outcomes included comparisons of IgG titers and factors associated with seropositivity, identified using univariate/multivariable analyses.
Researchers found that at 13 to 54 days after the second vaccine dose, 90% of patients with cancer (n = 92 of 102) and 100% of healthy controls were seropositive for COVID-19 antispike IgG antibodies. Patients with cancer had a significantly lower median IgG titer than controls (1,931 AU/mL vs. 7,160 AU/mL; P < .001).
Results of a multivariable analysis showed treatment with chemotherapy plus immunotherapy was the only variable significantly associated with lower IgG titers (beta, 3.5; 95% CI, 5.6 to 1.5).
“We observed adequate titers of anti-COVID-19 antibodies for patients who were on active cancer treatment for solid malignancies,” Stemmer said. “We have plans for future research as there are several open questions that remain, including: Will the antibody titer decrease require a third dose in patients? Also, what about cellular immunity?”
The results add to the multi-country perspective on the COVID-19 pandemic, which will be especially important considering variations in vaccine availability, schedules and practices across countries, according to an accompanying editorial by Lova Sun, MD, and Ravi B. Parikh, MD, MPP, both researchers at Perelman School of Medicine of University of Pennsylvania, and Jeremy L. Warner, MD, MS, researcher at Vanderbilt University.
“With at least 30 vaccines anticipated to be available worldwide by the end of 2021, it will be critical to determine which vaccines are most effective among patients with cancer,” they wrote. “Meanwhile, it is vitally important to continue transmission mitigation measures, within both community and health care settings, to help protect vulnerable patients with cancer from COVID-19 exposure, infection and life-threatening outcomes.”
For more information:
Salomon M. Stemmer, MD, can be reached at Davidoff Cancer Center, Jabotinsky St. 39, Petah Tikva 49100, Israel; email: firstname.lastname@example.org.