GlaxoSmithKline (GSK) and SK Bioscience have begun a phase 3 study of SK’s COVID-19 vaccine candidate, GBP510, in combination with GSK’s adjuvant.

The global late-stage study will enroll approximately 4,000 volunteers to compare GBP510, which is a nanoparticle vaccine, with AstraZeneca’s adenovirus-based COVID-19 vaccine. Results from the trial are expected during the first half of 2022.

If the vaccine is approved, the shot is expected to be shipped worldwide via the World Health Organization-backed COVAX vaccine-sharing program, the companies said.