Serologic Status and Toxic Effects of the SARS-CoV-2 BNT162b2 Vaccine in Patients Undergoing Treatment for Cancer

Abstract

IMPORTANCEThe efficacy and safety profile of SARS-CoV-2 vaccines have been acquired from phase 3 studies; however, patients with cancer were not represented in these trials. Owing to the recommendation to prioritize high-risk populations for vaccination, further data are warranted.OBJECTIVE To evaluate the use and safety of the BNT162b2 vaccine in patients undergoing treatment for cancer. DESIGN, SETTING, AND PARTICIPANTSIn January 2021, mass SARS-CoV-2 vaccination of high-risk populations, including patients with cancer, was initiated in Israel. This cohort study prospectively enrolled and followed up patients with cancer and healthy participants between January 15 and March 14, 2021. The study was conducted at the Division of Oncology of Rambam Health Care Campus, the major tertiary (referral) medical center of northern Israel. Participants included 232 patients with cancer who were receiving active treatment after the first and second doses of the BNT162b2 vaccine and 261 healthy, age-matched health care workers who served as controls.EXPOSURES Serum samples were collected after each vaccine dose and in cases of seronegativity. Questionnaires regarding sociodemographic characteristics and adverse reactions were administered at serum collection. A regulatory agencies-approved assay was used to assess IgG at all time points. Patients' electronic medical records were reviewed for documentation of COVID-19 infection and results of blood cell counts, liver enzyme levels, and imaging studies. MAIN OUTCOMES AND MEASURESSeroconversion rate after the first and second doses of the BNT162b2 vaccine and documented COVID-19 infection. RESULTSOf the 232 patients undergoing treatment for cancer, 132 were men (57%); mean (SD) age was 66 (12.09) years. After the first dose of BNT162b2 vaccine, 29% (n = 25) patients were seropositive compared with 84% (n = 220) of the controls (P < .001). After the second dose, the seropositive rate reached 86% (n = 187) in the patients. Testing rate ratios per 1000 person-days after the first dose were 12.5 (95% CI, 3.4-45.7) for the patients and 48.5 (95% CI, 37.2-63.2) for the controls. Patients undergoing chemotherapy showed reduced immunogenicity (odds ratio, 0.41; 95% CI, 0.17-0.98). In seronegative patients, the rate of documented absolute leukopenia reached 39%. No COVID-19 cases were documented throughout the study period; however, 2 cases in the patient cohort were noted immediately after the first dose. Reported adverse events were similar to data in former trials comprising mostly healthy individuals. CONCLUSIONS AND RELEVANCEIn this cohort study, the SARS-CoV-2 BNT162b2 vaccine appeared to be safe and achieve satisfactory serologic status in patients with cancer. There was a pronounced lag in antibody production compared with the rate in noncancer controls; however, seroconversion occurred in most patients after the second dose. Future real-world data are warranted to determine the long-term efficacy of the vaccine with regard to type of anticancer treatment.

Responses to SARS-CoV-2 Vaccination in Patients with Cancer (ReCOVer Study): A Prospective Cohort Study of the Hellenic Cooperative Oncology Group

“…Nearly 10% of our cancer patients were seronegative after two doses of vaccine, similar to the recently reported percentages of 6%, 10% and 14% [22,26,27]. Consistent with other series, most seronegative patients (88.9%) in our study were on active antineoplastic treatment, in most cases with chemotherapy alone.…”

“…Recent reports focused on cancer patients examined antibody responses following infection with COVID-19 [19,20], while data on immune responses elicited following SARS-CoV-2 vaccination in cancer patients have been published since April 2021 [21][22][23][24][25][26][27]. From these reports, it is evident that not all cancer patients are the same.…”

COVID-19 vaccination immune response in patients with solid organ and haematologic malignancies: call for active monitoring

“…To the best of author's knowledge, this is the first report of COVID-19 immune response in cancer patients in a limited resource setting. In our study, seroconversion rates were 50% following the first vaccine dose and 83% after the second dose, slightly lower than data from case series reported from high-income countries [7][8][9][10]. A bigger sample size from multiple sources is needed to infer correlations with the type of malignancy, treatment and vaccine type.…”

Effects of Age, Sex, Serostatus and Underlying Comorbidities on Humoral Response Post-SARS-CoV-2 Pfizer-BioNTech Vaccination – A Systematic Review

“…This may be due to daratumumab's mechanism of action that targets CD38 on the population of normal and tumor plasma cells, thus reducing vaccine immunogenicity by direct depletion of antibody producer cells. Nonetheless, Goshen-lago et al noted that while there was a pronounced lag in antibody production in cancer cases, seroconversion occurred in most patients after the second dose [66].…”