Immunogenicity of the high-dose influenza vaccine (HD IIV3) in patients with chronic lymphocytic leukemia (CLL) and monoclonal B-cell lymphocytosis (MBL, the precursor state to CLL) was found lower than reported in healthy adults according to a report in Vaccine.
In addition, immunogenicity to influenza B was found to be greater in those patients with MBL, compared with those with CLL.
“Acute and chronic leukemia patients hospitalized with influenza infection document a case fatality rate of 25%-37%,” according to Jennifer A. Whitaker, MD, of the Mayo Clinic, Rochester, Minn., and colleagues in pointing out the importance of their study.
The prospective pilot study assessed the humoral immune responses of patients to the 2013-2014 and 2014-2015 HD IIV3 (Fluzone High-Dose; Sanofi Pasteur), which was administered as part of routine clinical care in 30 patients (17 with previously untreated CLL and 13 with MBL). The median patient age was 69.5 years.
The primary outcomes were seroconversion and seroprotection, as measured by hemagglutination inhibition assay (HAI).
Lower response rate
At day 28 post vaccination, the seroprotection rates for the overall cohort were 19/30 (63.3%) for A/H1N1, 21/23 (91.3%) for A/H3N2, and 13/30 (43.3%) for influenza B. Patients with MBL achieved significantly higher day 28 HAI geometric mean titers (GMT), compared with CLL patients (54.1 vs. 12.1]; P = .01), In addition, MBL patients achieved higher day 28 seroprotection rates against the influenza B vaccine strain virus than did those with CLL (76.9% vs. 17.6%; P = .002). Seroconversion rates for the overall cohort were 3/30 (10%) for A/H1N1; 5/23 (21.7%) for A/H3N2; and 3/30 (10%) for influenza B. No individual with CLL demonstrated seroconversion for influenza B, according to the researchers.
“Our studies reinforce rigorous adherence to vaccination strategies in patients with hematologic malignancy, including those with CLL, given the increased risk of serious complications among those experiencing influenza infection,” the authors stated.
“Even suboptimal responses to influenza vaccination can provide partial protection, reduce hospitalization rates, and/or prevent serious disease complications. Given the recent major issue with novel and aggressive viruses such COVID-19, we absolutely must continue with larger prospective studies to confirm these findings and evaluate vaccine effectiveness in preventing influenza or other novel viruses in these populations,” the researchers concluded.
This study was funded by the National Institutes of Health. Dr. Whitaker reported having no disclosures. Several of the coauthors reported financial relationships with a variety of pharmaceutical and biotechnology companies.