mRNA COVID‐19 vaccines in patients with chronic lymphocytic leukemia: A systematic review and meta‐analysis

Current perspectives regarding SARS‐CoV‐2 vaccination in chronic lymphocytic leukemia

“…According to the results of a recent meta‐analysis, the rate of seroconversion was 73% in treatment‐naïve patients but only 29%–32% in patients on therapy with BTKi or BCL2i. 29 These results confirm the detrimental effect of BTKi on the antibody response to de novo antigens, as previously observed with the hepatitis B and influenza vaccine in patients receiving ibrutinib. 30 , 31 A practical implication is that COVID‐19 vaccination should be administered before initiating therapy with a BTKi.…”

“…Finally, the rate of seroconversion was only 4% in vaccinated patients within 12 months of their last anti‐CD20 antibody infusion. 29 Overall, these results suggest that SARS‐CoV‐2 vaccination should be offered before starting anti‐CD20 therapies. Furthermore, when feasible, physicians should delay administering anti‐CD20 monoclonal antibodies to prevent vaccination inefficacy.…”

“…Results of cohort studies and meta‐analyses indicate that the degree of humoral response to SARS‐CoV‐2 vaccines in patients with CLL appears to be lower than that observed in the general population. 13 , 14 , 15 , 16 , 23 , 25 , 26 , 27 , 28 , 29 , 30 Because of the potential immunosuppressive properties of different agents used to treat CLL, every effort should be made to vaccinate patients who intend to receive a SARS‐CoV‐2 vaccine (mRNA, replication‐deficient, or inactivated) before initiating treatment, unless a delay in initiation of therapy is clinically unacceptable. More data from larger cohorts of CLL patients are sorely needed, and information about various vaccines (both mRNA‐based and vector‐based) is still required.…”

“…Results of cohort studies and meta-analyses indicate that the degree of humoral response to SARS-CoV-2 vaccines in patients with CLL appears to be lower than that observed in the general population. [13][14][15][16]23,[25][26][27][28][29][30] Because of the potential immunosuppres- Finally, despite controversial data, there is no contraindication to the use of complementary measures for infectious prophylaxis in CLL which may include subcutaneous Ig administration. 54 In a small MOLICA ET AL.…”

A systematic review and meta-analysis of immune response against first and second doses of SARS-CoV-2 vaccines in adult patients with hematological malignancies

“…Notably, patients with CLL __ with the seropositivity rates of 22.0% and 47.8% following the first and second dose of vaccine, respectively __ had the lowest seropositivity rates, while those with MPN had the highest seroprotection after first dose and those with HL had the highest seroprotection after the second dose. A survey conducted on 42 patients with hematological malignancies also revealed that those with lymphoproliferative malignancies, especially CLL and NHL had less or no response to COVID-19 vaccines (135) . A meta-analysis on 13 studies involving 2,082 patients with CLL receiving mRNA COVID-19 vaccines showed a seroconversion rate of 52% (95%CI 48–74%) (136) , which was slightly higher than our findings; the discrepancy could be as a result of higher sample size of our study and the inclusion of all types of vaccines.…”