CML-127 Results of a Vaccination Against COVID-19 by a Vector Based Vaccine Sputnik V in Patients With Chronic Myeloid Leukemia

Introduction: Effectiveness and safety of new vaccines against new COVID-19 infection in patients with chronic myeloid leukemia (CML) need evaluation. Aim: To evaluate prospectively adverse events (AEs) and antibody formation after vaccination against SARS-CoV-2 in CML patients in a single center. CML patients applied for outpatient/remote consultations were suggested to report the post-vaccination AEs after the vector-based vaccine GamCovidVac (Sputnik V). At least 3 weeks after the 2nd injection patients were administered a blood test for SARS-CoV-2 spike(S) protein-specific antibodies by a semi-quantitative immunoassay (ELISA) which was considered positive at cut-off index (CI)>1. Other available tests for antibody detection were allowed as well. Results: Nighty-five chronic phase CML patients with a median (Me) age 54 years (range 29-89), received Sputnik V (DEC.2020–JUL.2021), 40(42%) were males. Me CML duration was 8 years (range 0-20), 75(79%) patients received TKIs at vaccination, 20(21%) were off-therapy: 17(18%) in treatment-free remission, 3(3%) with CML onset. Seventeen (18%) patients had a prior history of COVID-19. AEs were reported in 53(56%) patients: local pain/discomfort -30(31.5%), weakness/drowsiness -29 (30.5%), fever and/or chills -28(29%), other AEs -10(12%): headache, heartbeat, limbs/back pain, herpes reactivation. General reactions stopped in 1-2 days. No severe or life-threatening AEs were observed. Antibodies were detected in 66(93%) of 71 patients by any method, Me time after 2nd injection was 31 days (range 5-179). ELISA test was positive in 48(94%) of 55 tested patients with Me CI 7.7 (range 1.1-12), consistent with values of healthy people. Three of 7 negative by ELISA patients (Me age 58 years (range 40-70)) revealed antibodies by other tests with levels slightly above threshold. A very weak reverse correlation of the antibody levels with post-vaccination time (r =- 0.32) and with age (r =- 0.28) was observed. Conclusions: Sputnik V vaccine showed no unexpected or severe AEs in CML patients. Seroconversion rate of about 93-94% was close to the 3-phase trial data (94-97%). No strong age-dependent/time-dependent correlation of antibody levels was found in the tested time period. Sputnik V vaccination is safe and acceptable in CML patients.