Can a Third Dose of COVID-19 Vaccine Produce Antibodies in Seronegative Patients With CLL?
Posted: Thursday, December 23, 2021
A recent study suggested that some patients with chronic lymphocytic leukemia (CLL) who failed to respond to two COVID-19 mRNA vaccination doses may be more likely to develop an adequate antibody response following a third COVID-19 vaccination dose. Ohad Benjamini, MD, of the Sheba Medical Center, Ramat Gan, Israel, and colleagues published the results of this study in the journal Blood.
In the 172-patient study, seronegative patients with CLL or small lymphocytic leukemia were selected to give blood samples 3 weeks after their third dose of the BNT162b2 vaccine. Blood samples were analyzed for spike-specific IgG antibodies. Of the 172 patients, 23.3% were not receiving treatment for CLL, 58.1% were on active therapy, and 18.6% were previously treated.
An antibody response was seen in 41 of 172 patients (23.8%). These patients had a median antibody titer of 2 AU/mL. In treatment-naive and off-treatment patients, response rates were higher [40% (16 of 40) and 40.6% (13 of 32, respectively)], compared with actively treated patients (12%, 12 of 100).
Higher levels of anti–SARS-Cov-2S–receptor binding domain IgG titers were associated with patients aged 65 or younger, a lack of active treatment, and higher serum IgG and IgA levels. Additionally, Bruton’s tyrosine kinase inhibitors or venetoclax with or without anti-CD20 treatments were linked to poor antibody response; 1 of 28 patients treated with anti-CD20 antibodies less than 12 months before vaccination had an antibody response.
“These findings are of practical importance, as they show that a third dose can still achieve seroconversion, even in the more immunosuppressed subgroup of patients with CLL,’” they concluded.
Disclosure: The study authors reported no conflicts of interest.