Six Month Efficacy and Toxicity Profile of BNT162b2 Vaccine in Cancer Patients with Solid Tumors.

Waldhorn, Ithai; Holland, Roy; Goshen-Lago, Tal; Shirman, Yelena; Szwarcwort-Cohen, Moran; Reiner-Benaim, Anat; Shachor-Meyouhas, Yael; Hussein, Khetam; Fahoum, Liana; Peer, Avivit; Almog, Ronit; Shaked, Yuval; Halberthal, Michael; Ben-Aharon, Irit

We had previously reported short-term efficacy, immunogenicity and safety of BNT162b2 vaccine among cancer patients with solid tumors. We aimed to evaluate these outcomes at 6-months post-vaccination. Study cohort comprised of patients who were on treatment during vaccination and throughout 6-months post-vaccination. Serological tests were performed after second vaccination and 6-months afterwards. An age-matched cohort of healthcare workers served as controls. Documentation of COVID-19 infection, blood tests and imaging studies during study period was reviewed. Participants included 154 patients and 135 controls. Six-months post-vaccination, 122(79%) of patients were seropositive compared with 114(84%) of controls (p-0.32). Serology titer dramatically decreased similarly in both cohorts. No COVID-19 cases were documented in controls and one case occurred in patient cohort. All previously reported adverse effects resolved. Taken together, the pattern of immunogenicity, efficacy and safety of BNT162b2 in cancer patients with solid tumors at 6 months post-vaccination resemble that of the general population.