THURSDAY, May 6, 2021 (HealthDay News) -- The BNT162b2 mRNA COVID-19 vaccine has lower efficacy among patients with chronic lymphocytic leukemia (CLL) and induces lower neutralizing antibody responses (NAbs) in elderly patients with multiple myeloma (MM) versus controls, according to two studies published online April 16 in Blood.
Yair Herishanu, M.D., from Tel Aviv University in Israel, and colleagues assessed humoral immune responses to the BNT162b2 mRNA COVID-19 vaccine in patients with CLL and age-matched healthy controls. The researchers found that the antibody response rate was 39.5 percent among 167 patients with CLL. In a comparison of 52 patients with CLL and 52 sex- and age-matched healthy controls, the response rate was significantly reduced among CLL patients (52 versus 100 percent; adjusted odds ratio, 0.010). The highest response rate was seen in patients who obtained clinical remission after treatment (79.2 percent), followed by 55.2 and 16 percent, respectively, in treatment-naive patients and patients under treatment at the time of vaccination.
Evangelos Terpos, M.D., from the National and Kapodistrian University of Athens, Greece, and colleagues reported the development of NAbs against severe acute respiratory syndrome coronavirus 2 in 48 elderly MM patients and 104 controls (median age in both groups, 83 years) after the first dose of the BNT162b2 vaccine. The researchers found that on day 22, MM patients had lower NAb titers than controls (median NAb inhibition titers and range, 20.6 versus 32.5 percent). Only 25.0 percent of MM patients and 54.8 percent of controls developed NAb titers ≥30 percent (cutoff defining positivity). Overall, 8.3 percent (four) and 20.2 percent (21) of MM patients and controls, respectively, developed NAb titers ≥50 percent (clinically relevant viral inhibition); all four MM patients were in remission.
"Patients with MM often present suboptimal seroconversion rates after a single-dose vaccine against bacteria and viruses and, therefore, booster doses are needed to assure adequate protection, such as in the case with the seasonal flu vaccine," Terpos and colleagues write.
Several authors from the Herishanu study disclosed financial ties to the pharmaceutical industry.
Abstract/Full Text - Herishanu (subscription or payment may be required)
Abstract/Full Text - Terpos (subscription or payment may be required)
