Six months after receiving their second dose of the BNT162b2 vaccine (Comirnaty), patients with solid tumours retained similar levels of SARS-CoV-2 antibodies in their blood compared to individuals without cancer, according to results of a study published in Cancer Discovery, a journal of the American Association for Cancer Research.

The study, led by Irit Ben-Aharon, MD, PhD, director of the oncology division at Rambam Health Care Campus in Israel, evaluated long-term serology status, safety profile, and infection rate after vaccination against COVID-19 in patients with solid tumours.

Ben-Aharon and colleagues measured serology titers in 154 patients actively undergoing treatment for solid tumours and 135 age-matched controls approximately six months after their second dose of the BNT162b2 vaccine, and compared to titers measured shortly after the second vaccination.

They found that 79 percent of the patients were seropositive, which was comparable to 84 percent of the controls, though antibody levels declined drastically throughout the six-month period in both groups. Among the seronegative patients, 81 percent were undergoing chemotherapy.

“In our study we saw that in all outcomes, including immunogenicity, infectivity rate throughout the six-month period, and safety, patients with solid tumors depicted a similar trend as the general population,” Ben-Aharon said.

These data can help inform recommendations surrounding the prioritisation of different groups for booster vaccines, Ben-Aharon said, including the most recent guidelines from the National Comprehensive Cancer Network (NCCN).

The NCCN recommends prioritising patients with haematological malignancies and those who underwent haematopoietic cell transplantation or cellular therapy, followed by patients with solid tumour malignancies.

Source: American Association for Cancer Research (AACR)