Cytomegalovirus Update: For the First Time, a Phase 3 Vaccine Trial | IDWeek 2023

Fourth of four parts

It’s a first in cytomegalovirus vaccine development.

“It is an exciting that for the first time in the 50 years of CMV vaccine development we have a phase 3 trial underway,” said Sallie Permar, M.D., Ph.D., in recent interview with Managed Healthcare Executive.

The trial (NCT05085366) is of a vaccine that Moderna developed and it uses the same mRNA technology that the company used to develop its COVID-19.

In addition, Permar explained, the Moderna vaccine candidate has a pentameric complex that that holds the promise of making the vaccine more effective. Permar said Moderna has been reticent about giving timeline, but she said she is hoping that there will be results in the next year and a half.

Permar gave a talk this afternoon at the ID Week 2023 meeting in Boston titled “CMV Vaccines: Where Are We Now?” She is leading researcher of the prevention and treatment of neonatal viral infections,is chair of the Department of Pediatrics at Weill Cornell Medicine in New York and pediatrician-in-chief at NewYork-Presbyterian/Weill Cornell Medical Center and the NewYork-Presbyterian Komansky Children’s Hospital.

Permar said the Moderna vaccine has raised hopes partly it is using the mRNA technology that now has an established safety track record because of the COVID-19 mRNA vaccines, both Moderna's and Pfizer's. Safety concerns are paramount with CMV vaccine because women of childbearing age would be a target population with the aim of reducing the number of cases of congenital CMV.

Permar also mentioned promising early data showing that the Moderna's CMV vaccine candidate induced neutralizing antibodies in epithelial cells and endothelial cells apparently because the pentameric complex enables entry into those types of cells.

Merck is also developing a CMV vaccine. It does not, however, use mRNA technology. Permar said results from a phase 2B trial showed that the Merck vaccine was partially effective but that when the case definitions were narrowed the efficacy rate calculations improved.