Phase 3 trial begins for SK bioscience and GSK COVID-19 vaccine candidate

Approximately 4,000 people from all over the world will be enrolled in a Phase 3 trial of a combined SK bioscience and GlaxoSmithKline plc (GSK) adjuvanted COVID-19 vaccine candidate beginning this week.

The trial will combine the SK COVID-19 vaccine candidate GBP510 with GSK’s pandemic adjuvant, comparing its results to those of the AstraZeneca/Oxford University COVID-19 vaccine. Randomized and active-controlled, the trial will also mark one of the first global Phase 3 trials to actively pit two different COVID-19 vaccine candidates against one another for the evaluation of safety and immunogenicity.

“While many countries have made good progress with vaccination, there remains a need for accessible and affordable COVID-19 vaccines to ensure equitable access and to protect people across the world,” Thomas Breuer, chief global health officer of GSK, said. “We are pleased to contribute with GSK’s pandemic adjuvant and to be working with SK to deliver the vaccine at scale via COVAX if it is approved.”

In Phase 1/2 data, all recipients of the adjuvanted vaccine candidate developed strong neutralizing antibody responses to COVID-19. In fact, neutralizing antibody titers were between five to eight times higher than those who have recovered from COVID-19 naturally. Additionally, no safety concerns emerged during the trial.

“We are grateful that we were able to advance to the Phase 3 study with the unprecedented support of global initiatives, including GSK, Coalition for Epidemic Preparedness Initiative (CEPI), and the Bill & Melinda Gates Foundation (BMGF),” Jaeyong Ahn, CEO, SK bioscience said.

Now, the partners aspire to begin global supply of their adjuvanted vaccine candidate through the COVAX facility — a joint effort on the part of the World Health Organization, the Coalition for Epidemic Preparedness Innovations and Gavi, the vaccine alliance — within the first half of 2022. That will depend on data and regulatory review, though, and results from Phase 3 are expected in the same period.