Antibody Responses after SARS-CoV-2 Vaccination in Lymphoma

Individuals with lymphoid malignancies have an increased mortality risk from COVID-19. Paradoxically, this population is least likely to be protected by SARS-CoV-2 vaccination as a result of disease- or treatment-related immunosuppression. Current data on vaccine responses in persons with lymphoid malignancies is limited.

PROSECO is a UK multi-centre prospective observational study evaluating COVID-19 vaccine immune responses in individuals with lymphoma. This early interim analysis details the antibody responses to first- and second-SARS-CoV-2 vaccination with either BNT162b2 (Pfizer-BioNTech) and ChAdOx1 (AstraZeneca), in 129 participants. Responses are compared to those obtained in healthy volunteers.

The key findings of this interim analysis are first, 61% of participants who are vaccinated during or within 6 months of receiving systemic anti-lymphoma treatment, do not have detectable antibodies despite two doses of vaccine. Second, individuals with curable disease such has Hodgkin (6/6) and aggressive B-cell non-Hodgkin lymphoma (13/16) develop robust antibody levels to either first or second doses, when vaccinated > 6 months after treatment completion. Third, participants incurable, indolent lymphomas have reduced antibody levels to first and second vaccine doses, irrespective of treatment history. Finally, whilst there was no difference in antibody responses between BNT162b2 and ChAdOx1 in lymphoma participants, BNT162b2 induces 11-fold higher antibody responses than ChAdOx1 after the second dose in healthy donors.

These findings serve to reassure the community that individuals with treated Hodgkin and aggressive B-NHL can develop antibody responses to SARS-CoV-2 vaccine. Simultaneously it also highlights the critical need to identify an alternative strategy against COVID-19 for those undergoing systemic anti-lymphoma treatment, and for individuals with indolent lymphomas.