On Aug. 9, 2021, Inovio Pharma announced that it had received regulatory allowance for two clinical trials investigating heterologous boosting with INO-4800, its DNA vaccine candidate for COVID-19, through partner and trial-sponsor Advaccine Biopharmaceuticals together with Sinovac Biotechnology.

The studies evaluated the safety, tolerability and immunogenicity of heterologous prime-boost sequential immunizations using INO-4800 and CoronaVacﾮ, an inactivated COVID-19 vaccine developed by Sinovac and validated by the World Health Organization for emergency use.