U.S. pharmaceutical giant Pfizer Inc. and its German partner BioNTech SE said Tuesday they are starting a clinical study to evaluate the safety of an experimental vaccine targeting the new Omicron variant of the coronavirus.
The study will be conducted in adults aged 18 to 55 and will involve up to 1,420 participants.
While noting that a booster shot after the primary two-shot series of the existing COVID-19 vaccine offers high protection against severe disease from Omicron, Kathrin Jansen, head of vaccine research and development at Pfizer, said, "We recognize the need to be prepared in the event this protection wanes over time and to potentially help address Omicron and new variants in the future."
Ugur Sahin, CEO and co-founder of BioNTech, said the study is expected to help develop a "variant-based vaccine that achieves a similar level of protection" against the highly transmissible Omicron as it did against earlier variants, but with longer duration of protection.
The study will look into three groups, including a group of 615 people who received two doses of Pfizer's current COVID-19 vaccine between 90 and 180 days prior to enrollment in the study. They will receive one or two doses of the Omicron-targeted vaccine.
Another group of about the same size will consist of individuals who have received three COVID-19 vaccine doses and will receive one dose of the current vaccine or the Omicron-targeted vaccine.
The remaining group will be 200 people who are unvaccinated and will receive three doses of the vaccine against Omicron.