Prospective Biological Study to Evaluate the Persistence of COVID-19 Vaccine and Other Vaccines'-Induced Immune Responses in Follicular Lymphoma Patients Undergoing Frontline Induction Immuno-chemotherapy and Anti-CD20 Maintenance

Patients (pts) with follicular lymphoma (FL) were reported to be at high risk for hospitalization and death from COVID-19 infection, especially if exposed to anti-CD20 monoclonal antibodies (mAbs)-based therapy. A large amount of studies unequivocally demonstrated that anti-CD20 mAbs-containing therapies typically impair the development of protective levels of neutralizing anti-spike antibodies after immunization with full course of approved mRNA-based COVID-19 vaccines (up to 12 months after last anti-CD20 infusion). Moreover, booster doses seem to induce seroconversion only in a minority of such pts. On the contrary, preliminary findings seem to suggest that a substantial proportion of vaccinated pts with B-cell lymphoma (B-NHL) mount detectable SARS-CoV-2-specific T-cell responses (as measured by assays evaluating IFN-Y secretion after stimulation with SARS-CoV-2 peptides), independently from humoral response status.

For newly diagnosed FL pts current guidelines suggest to complete the vaccination with booster dose(s) before treatment initiation, as anti-CD20 mAbs seems to spare pre-established humoral immunity to COVID-19 vaccine, although data supporting this finding are scanty.5 Furthermore, data about long term persistence of pre-established cellular immunity in this setting are lacking, although preliminary findings in unselected immunosuppressed pts suggest that it decline over time without significant difference with respect to the general population.

The novel adjuvanted recombinant zoster vaccine demonstrated lower humoral immune response in pts with B-NHL with respect to other pts, probably due to anti-CD20 therapy, while cellular immunity was not affected, although the small number of pts requires further investigation.

Very few data concerning persistence of immunity to childhood vaccines after anti-CD20-based therapy are available and suggest that humoral immunity to diphtheria and tetanus may be significantly impaired after therapy.

This is a prospective biological study evaluating the persistence of COVID-19 vaccine and other vaccines' (zoster, diphtheria and tetanus)-induced immunity in a subgroup of FL patients undergoing frontline induction immuno-chemotherapy and anti-CD20 maintenance within the prospective FIL_FOLL19 study (NCT05058404).