Patient samples for serology testing were obtained after median time of 14 days (range, 14-28) from the second vaccine dose
Patient samples for serology testing were obtained after median time of 14 days (range, 14-28) from the second vaccine dose. Median age of BST2 CLL pts was 72 years (range, 63-88) and 71.4% Ropidoxuridine were males. the second vaccine dose. Median age of CLL pts was 72 years (range, 63-88) and 71.4% were males. The median time from CLL diagnosis to vaccination was 82.5 mo. (range, 1-280). Twenty-three pts (32.9%) were treatment na?ve (TN), 36 (51.4%) on active therapy (i.e., BTKi, 22; anti-BCL2 12; PI3Ki,1; cyclophosphamide,1) and 11 (15.7%) off-therapy (i.e., 8 in complete [CR] or partial remission [PR], and 3 in CLL relapse). Of note, 9 (25.7%) of 35 pts on therapy with a pathway inhibitor (PI) at the time of vaccination had been given an anti-CD20 antibody. The vaccine elicited an antibody-mediated response in 41 (58.5%) of the 70 CLL pts. An inferior response rate [RR] (58.5% vs 100%, OR, 0.012 [0.0007-0.206];P=0.02) and a lower antibody titers (median, 58 AU/ml; range, 1.8-800 vs. 284 AU/ml; range, 14-800; P 0.0001) were observed in CLL pts in comparison to age-matched subjects with no hematological malignancy. The RR was higher in TN (87%) or off-therapy pts with sustained clinical response (87.5%) in comparison to pts on therapy at the time of vaccination (41.7%)( 0.0001). Similar results were observed when comparison was performed in terms of antibody titers (P=0.02;Kruskall-Wallis test; Fig 1). In comparison to pts treated with a PI as monotherapy, those who received an anti-CD20 antibody in association to PI had a lower antibody response to SARS-CoV-2 vaccine (11.1% vs 53.8%; OR,0.107 [0.011-0.984];P=0.04). In univariate analysis, the following variables were significantly associated with serological response to SARS-CoV-2 vaccination: early Rai stage (i.e.,0-I) (OR, 0.36 [0.13-0.97];P=0.04), mutated IGHV status (OR,0.30 [0.10-0.88]; P=0.02), lack of active therapy – which comprised TN and off-therapy pts with Ropidoxuridine sustained response – (OR,0.09 [0.03-0.32];P 0.0001), and no anti-CD20 antibody exposure preceding vaccination (OR, 013 [0.01-1.23];P=0.04). Levels of immunoglobulins Ropidoxuridine or absolute values of CD3,CD4,CD8, and CD16/CD56 cells measured before the first COVID-19 vaccination were not associated to vaccine response. Of note, in pts who experienced a serological response a concomitant increase of the absolute of CD16/CD56 positive cells was observed (P=0.02). Finally, Rai stage (OR, 0.19 [0.05-0.79]; P=0.02) and treatment status (OR, 0.06 [0.02-0.27]; P 0.0001) were independent predictors of response in multivariate analysis. We used these factors to build a score that identified pts with different pattern of response to vaccine. Serologic response to SARS-CoV-2 vaccination was 100% in pts with no factor (n=21), 45% in pts. with one factor (n=38) and 36% in pts with two factors (n=11) (P 0.0001). In agreement with results of recent studies (Herishanu et al, Blood 2021; Roeker et al, Leukemia 2021;Perry et al, Blood Cancer J. 2021; Benjamini O et al, Haematologica 2021 ) our findings suggest that antibody-mediated response to COVID-19 vaccination is significantly reduced in Ropidoxuridine CLL and influenced by Ropidoxuridine disease activity and treatment status. The serological response to SARS-CoV-2 vaccination observed in pts. with early disease with no need of therapy may help to identify CLL pts who are expected to achieve an optimal response to COVID-19 vaccine similarly to age- and sex-matched controls. Figure 1 Open in a separate window Disclosures Molica:? Honoraria; Consultancy, Honoraria; Consultancy, Honoraria..