Eliakim-Raz N, Massarweh A, Stemmer A, et al. - The initial findings from a prospective cohort study of patients with solid tumors on active anticancer treatment vs healthy controls revealed seropositivity in 90% of the patients with cancer (90/102) and 100% of the healthy controls (78/78) after a median of approximately 5.5 weeks from the second dose of the SARS-CoV-2 BNT162b2 messenger RNA (mRNA) vaccine (BioNTech-Pfizer). Significantly lower median IgG titers were recorded in the patients relative to the controls. Herein, the patients with cancer were compared with the controls with respect to their antispike (anti-S) IgG antibody response approximately 4 months after the second vaccine dose.

• In the current analysis, researchers analyzed 95 of 102 patients (5 died, 2 withdrew) and 66 of 78 controls (12 withdrew).

• Findings revealed a consistently high seropositivity rate among the patients with cancer (87%) approximately 4 months after the second BNT162b2 vaccination dose.

• There appeared a decrease in the median IgG titer in the patients and the controls over time.

• Notably, in both the previous and the current analysis, the patients with cancer showed statistically significantly lower IgG titers when compared with the controls.

• There were limited data on the durability of protection after vaccination for healthy participants and data were lacking for oncological patients.

• Thirty-four participants showed raised antibody levels persisting 3 months after the second dose of mRNA-1273 vaccine (Moderna), although there appeared a slight decrease in antibody levels.

• As per interim results from a phase 3 trial of the mRNA-1273 vaccine in 33 healthy adults, all age groups consistently had high antibody activity after approximately 7 months.

• The accumulating evidence supports antibody response as a potential correlate of disease protection.