Immunity induced by the COVID-19 mRNA vaccines wanes over time in patients with renal cell carcinoma (RCC), according to a poster presentation at IKCS Europe 2022. The finding is consistent with that of other recent studies.

In the study presented at IKCS, blood was collected before and after the first dose of a COVID-19 mRNA vaccine from 32 patients with RCC. The most frequently administered vaccines were Pfizer (68.8%) and Moderna (31.2%). Antibody titers were assessed using the SCoV-2 Detect IgG ELISA assay at baseline, 2 months, and 6 months. Of the cohort, 56.3% received immunotherapy, 40.6% targeted therapy, and 3.1% no treatment.

An immune status ratio (ISR) value of more than 1.1 was used to indicate the presence of IgG antibodies specific to SARS CoV 2. Mean ISR values increased from 0.72 at baseline to 6.51 at 2 months, then significantly declined by 24% to 4.93 at 6 months, Jasnoor Malhotra, BSc, of City of Hope Comprehensive Cancer Center in Duarte, California, reported. Both patients who did and did not receive immunotherapy experienced waning. The investigators found, however, that 1 seronegative patient had T-cell response to COVID-19 spike proteins.


Continue Reading

The vast majority of patients (96.9%) were receiving systemic treatment, including 58.1% receiving immune checkpoint inhibitors and 41.9% receiving other targeted agents.

“Our results suggest waning immunity over time in patients with RCC,” Malhotra and colleagues concluded. “Strategies to prolong host immunity against SARS COV-2 (e.g., booster vaccination) are warranted.”

In a 2021 study published in Cancer Discovery, Ithai Waldhorn, MD, and colleagues similar found a steady decline in antibody titers and seropositivity rates at 6 months after the second dose of an mRNA vaccine among patients with solid tumors treated at a center in Haifa, Israel, that were comparable with the general population.

Their latest study published April 2022 in JAMA Oncology further characterizes cellular and humoral responses to the Pfizer mRNA vaccine at 6 months after standard vaccination in patients with a solid cancer (21 with genitourinary cancer) who were receiving active antineoplastic treatment, as well as a subset of patients following receipt of a booster dose. Of the full cohort, 81% had metastatic cancer. Treatments included chemotherapy (57%), biological agents (36%), immunotherapy (37%), or combined modalities.

Among the subset of patients receiving a booster dose of a COVID-19 vaccine, all had a significant increase in antibody levels (117 vs 732 AU/mL), whereas 67% also had a significant increase in cellular immune response (9.2 vs 31.3 spot forming units/106 peripheral blood mononuclear cells).

Dr Waldhorn’s team noted that they “found a durable cellular and humoral response in patients with cancer with solid tumors who were receiving active treatment.

“Humoral and cellular response were associated, although B-cell response was negatively associated with chemotherapy, whereas T-cell response seemed to be unaffected, which may have been associated with a differential association of chemotherapy with B-cell counts.”

The investigators pointed out that variants, such as Omicron, can evade a B-cell response but are associated with a T-cell response. “Thus, T-cell response might confer immunity to SARS-CoV-2 in seronegative patients.”

References

1. Malhotra J, et al. Waning efficacy of COVID-19 vaccination at 6 months in patients with renal cell carcinoma (RCC). Presented at IKCS Europe 2022 in Antwerp, Belgium; April 22-24, 2022. Poster 10.

2. Waldhorn I, Holland  R, Goshen-Lago T, et al. Six-month efficacy and toxicity profile of BNT162b2 vaccine in cancer patients with solid tumors. Cancer Discov. 2021;11(10):2430-2435. doi:10.1158/2159-8290.CD-21-1072

3. Waldhorn I, Holland R, Goshen-Lago T, et al. Long-term immunogenicity of BNT162b2 vaccine in patients with solid tumors. JAMA Oncol. Published online April 22, 2022. doi:10.1001/jamaoncol.2022.1467

This article originally appeared on Renal and Urology News