Inovio has obtained regulatory approval from China’s Center for Drug Evaluation of the National Medical Products Administration to conduct two clinical trials of heterologous prime-boosting with its Covid-19 vaccine candidate, INO-4800.

INO-4800 contains a specifically designed deoxyribonucleic acid (DNA) plasmid. It can be injected intradermally with subsequent electroporation to carry the DNA plasmid directly into body cells.

The company’s partner, Advaccine Biopharmaceuticals Suzhou, will sponsor the open-label, positive-control trials, conducted in partnership with Sinovac Biotechnology.

The trials will analyse the safety, tolerability and immunogenicity of sequential immunisations with a mixed regimen of INO-4800 and Sinovac’s inactivated Covid-19 vaccine, CoronaVac.

CoronaVac was validated for emergency use by the World Health Organization (WHO).

Anticipated to begin in the coming months, the trials will enrol healthy adults aged 18 years and above in China.

In cross prime-boost pre-clinical animal studies of the vaccines, the companies found that the prime-boost regimen can induce increased levels of antigen-specific binding antibodies, neutralising antibodies and antigen-specific T cell immune responses.

Inovio president and CEO Dr J Joseph Kim said: “If approved, we believe INO-4800 will be well-positioned to serve the vaccine needs of the global community as both a primary and a booster vaccine due to its tolerability, balanced cross-reactive immune responses and strong thermostability profile that does not require cold or ultra-cold-chain transport.”

In June, Inovio extended collaboration with Advaccine to co-perform the global Phase III segment of the ongoing Phase II/III INNOVATE trial.

The Phase III efficacy part will be initially carried out in Latin America, Asia and Africa among other countries.

According to the latest analysis of clinical samples, INO-4800 preserved a strong T cell level against the delta variant of SARS-CoV-2 compared to the original wildtype strain.

This data shows the potency of the INO-4800 vaccine to produce a cluster of differentiation 8 (CD8) T cells, which could be vital in mitigating emerging variants, Inovio noted.

These results are in line with data from Phase I and Phase II trials of INO-4800, which demonstrated the vaccine’s ability to stimulate a balanced immune response, including T cell and B cell engagement.