(HealthDay News) — A single dose of AZD7442 is effective for preventing COVID-19, according to a study published online April 20 in the New England Journal of Medicine.
Myron J. Levin, M.D., from the University of Colorado School of Medicine in Aurora, and colleagues conducted an ongoing phase 3 trial involving adults with an increased risk for an inadequate response to vaccination against COVID-19, an increased risk for exposure to severe acute respiratory syndrome coronavirus 2, or both.
A total of 5,197 participants were randomly assigned to receive a single dose of AZD7442 (two consecutive intramuscular injections of tixagevimab and cilgavimab) or saline placebo (3,460 and 1,737 individuals, respectively). In the primary analysis, the participants were followed for up to 183 days.
The researchers found that 35.3 and 34.2 percent of participants in the AZD7442 and placebo groups, respectively, reported having at least one adverse event, which were mostly mild or moderate in severity.
Symptomatic COVID-19 occurred in 0.2 and 1.0 percent of participants in the AZD7442 and placebo groups, respectively (relative risk reduction, 76.7 percent); the relative risk reduction was 82.8 percent at extended follow-up at a median of six months.
There were five cases of severe or critical COVID-19 and two COVID-19-associated deaths, all of which occurred in the placebo group.
“The results of this trial support the use of a single dose of AZD7442 (two consecutive intramuscular injections) for the prevention of symptomatic and severe COVID-19,” the authors write.
Several authors disclosed financial ties to pharmaceutical companies, including AstraZeneca, which manufactures AZD7442 and funded the study.