Immunity against SARS-CoV-2 appears to wane over time in genitourinary cancer patients following COVID-19 vaccination, suggesting that strategies to prolong host immunity must be researched, according to findings presented at the 2022 American Society of Clinical Oncology (ASCO) Genitourinary Cancers Symposium.
The study included a total of 183 patients with genitourinary cancers (median age, 66 years; range, 48-85) who had not been vaccinated against COVID-19. Of these patients, 55.9% (n=33) had prostate cancer, 42.4% (n=25) had kidney cancer, and 1.7% (n=1) had bladder cancer; 93.2% of patients were being treated with systemic therapy, with 23.7% receiving immune checkpoint inhibitors, 18.6% receiving targeted therapy, and 1.7% receiving chemotherapy.
Baseline blood samples of 136 patients were collected and 59 patients provided blood samples at the 2- and 6-month timepoints following administration of 1 dose of either adenovirus- or mRNA-based COVID-19 vaccine. Blood samples of patients who were receiving systemic therapy were also collected at 3 consecutive therapy cycles post vaccination. Results of the analysis were reported as immune status ratios (ISRs).
“The mean (±standard deviation) ISR values at baseline and 2 months were 0.68±1.59 and 6.62±1.75, respectively,” the study authors reported. They added, “At the 6-month timepoint, mean ISR was 5.46±1.61; this was significantly lower than the 2-month antibody titers (P <.0001), and reflects a reduction of 17.6%.”
Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Zengin ZB, Meza LA, Malhotra J, et al. Waning efficacy of COVID-19 vaccination at 6 months in patients (pts) with genitourinary malignancies. Presented at: ASCO-GU 2022; February 17-19, 2022; Abstract 185.
This article originally appeared on MPR