Patients actively undergoing cancer treatment found to respond positively to the Pfizer COVID vaccine

16 Jul 2021
Patients actively undergoing cancer treatment found to respond positively to the Pfizer COVID vaccine

By ecancer reporter Jarka Meleszkiewicz

The (SARS-CoV-2) BNT162b2 vaccine has been shown to be safe and achieve satisfactory serologic status in patients with cancer, according to a study published in JAMA Oncology.

The study is the first to prospectively review serologic status, immunogenicity and safety of the BNT162b vaccine in a cohort of patients with solid tumours receiving active anticancer therapies.

On 10 January 2021 Israel launched its mass vaccination programme in accordance with data obtained during phase 3 trials on the safety and efficacy of SARS-CoV-2 vaccines.

Although patients with malignancies were not excluded from these trials, those who were actively in receipt of anticancer therapy were not represented during assessments of BNT163b2 and mRNA-1273 (Moderna) vaccine efficacy.

The authors of the study felt that further investigation in this field was warranted due to recommendations prioritising high-risk populations for vaccination and the fact that some studies reported patients with malignancies such as metastatic cancer or haematologic neoplasms were potentially at risk of a severe clinical course of COVID-19.

It was conducted at the Rambam Health Care Campus in Haifa with enrolment taking place during routine visits among vaccinated (first and/or second dose) patients undergoing active therapy. There was a two-month follow-up period.

Serologic testing was carried out either 10 days after the first dose or 14 days after the second dose in 232 patients with malignancies and this was compared against serologic test results for an age-matched, randomly generated cohort of 261 health care workers.

Serum samples were analysed for the detection of anti–SARS-CoV-2 antibodies with questionnaires about sociodemographic characteristics and adverse reactions being conducted at the time serum was collected.

It was found that 29% of patients with cancer were seropositive after the first dose compared with 84% of the control group. The seropositive rate subsequently increased to 86% in the patient cohort, once they had received their second dose of the vaccine.

The median age of the patient cohort was relatively high (68-years-old) which may have affected the immune response as its reciprocal association with age has previously been documented, however, adverse events were similar to those reported during previous trials – comprised mostly of healthy individuals.

No cases of COVID-19 were reported during the study period, although two participants from the patient cohort were diagnosed with the disease immediately after they had received their first vaccine dose.

The authors suggested that post-vaccination infection rates may have been lower due to an increased likelihood of cancer patients adhering to recommended safety measures, however, they concluded that the overall results of the study were positive and the vaccine appeared safe and achieved satisfactory serologic status in patients after the second dose.

References: Goshen-Lago T, Waldhorn I, Holland R, et al. Serologic Status and Toxic Effects of the SARS-CoV-2 BNT162b2 Vaccine in Patients Undergoing Treatment for Cancer. JAMA Oncol. Published online July 08, 2021. doi:10.1001/jamaoncol.2021.2675