COVID-19 Vaccination Effectiveness in Patients With CLL: Focus on Humoral Response

By: Joseph Fanelli
Posted: Tuesday, February 22, 2022

According to findings presented in the journal Blood, patients with chronic lymphocytic leukemia (CLL) should consider postponing the start of treatment with Bruton’s tyrosine kinase (BTK) inhibitors until after receiving COVID-19 vaccinations or should consider venetoclax monotherapy instead. On behalf of the French Innovative Leukemia Organization, Anne-Sophie Michallet, MD, of the Centre Léon Bérard, Lyon, France, and colleagues proposed these suggestions after reviewing the vaccination results of patients with CLL; the findings revealed that ongoing treatment with BTK inhibitors was a major independent predictor of negative humoral response to vaccines.

“In light of these national-level data, patients who remain seronegative after a third dose will soon be offered the possibility of receiving SARS–CoV-2 neutralizing monoclonal antibodies,” the authors concluded.

In this trial, the authors evaluated 503 patients with CLL who received a COVID-19 vaccine in France. Responses were evaluated for 158 patients after dose one, 506 patients after dose two, and 95 patients after dose three. BNT162b2 vaccines were given to 377 patients (71%), and 76 patients received mRNA-1273 vaccines. Investigators did not specify the type of vaccine for the remaining 77 patients. In total, 218 patients (40%) were treatment-naive upon receiving the vaccine, 136 (26%) had received previous treatment but were off therapy, and 176 (34%) were currently receiving treatment.

The authors found that after dose two, treatment-naive patients had the highest antibody response rate to vaccination (72%), followed by patients previously treated with chemoimmunotherapy (60%).

For patients receiving therapy, those who received BTK inhibitors alone or in combination with anti-CD20 monoclonal antibodies or venetoclax had the poorest response rate from vaccinations (22% and 0%, respectively) compared with patients who received venetoclax monotherapy, who achieved a significantly higher response rate (52%). A multivariable analysis revealed that age of 65 and older, ongoing CLL treatment, and gamma globulin levels of at least 6 g/L or more were all independent predictors of the absence of seroconversion.

Disclosure: The authors reported no conflicts of interest.

Blood

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