Title: CLL-370: The Prolonged Positivity of SARS-CoV-2 RNA in Chronic Lymphocytic Leukemia Patients
Abstract: Patients were divided into two cohorts based on treatment received: cohort A (N=14) received cladribine 5.6 mg/m 2 intravenously (IV) for 7 days as a single agent, and cohort B (N=15) received the same dose of cladribine followed by rituximab 375 mg/m 2 IV weekly for eight doses.Rituximab consolidation was given after a median time of 33 days (17-60 days) from cladribine completion.Complete remission rates were 64% and 100% in cohorts A and B, respectively.In cohort A, seven (50%) patients relapsed after a median duration of 48 months (range: 1-209 months), requiring second-line treatment with cladribine followed by rituximab.In cohort B, no relapses occurred.After a median follow up of 67 months (range: 1-227 months), the 5-year disease-free survival was signifi cantly better in group B (100%) compared to group A (58%) (HR=0.16,95% CI: 0.032-0.84,p=0.03).There was no signifi cant difference in overall survival between the two groups.Grade 3/4 adverse events were observed in 92%% and 80% of patients in cohorts A and B, respectively, mainly neutropenia (78.5% vs 66.6%) and febrile neutropenia (71% vs. 40%).One patient in cohort B who received rituximab consolidation too early (day 17) died from febrile neutropenia and septic shock.Conclusion: Consolidation rituximab after cladribine in frontline treatment of classical HCL showed high response rate of 100% and translated into a signifi cant improvement in disease-free survival.Cladribine followed by rituximab consolidation may be considered as standard fi rst-line therapy of HCL.