ImmunityBio and NantKwest have dosed the first patient in the Phase I clinical trial of the novel vaccine candidate, hAd5-COVID-19.

The two companies began working on vaccines and drugs to fight against Covid-19 in April.

HAd5-COVID-19 activates both T-cells and antibodies against the coronavirus (SARS-CoV-2) and targets the inner nucleocapsid (N) and the outer spike (S) protein.

This second-generation human adenovirus serotype 5 vaccine delivers multiple proteins of the virus with the potential for long-term immunity through memory T-cells.

ImmunityBio and NantKwest chairman and CEO Dr Patrick Soon-Shiong said: “Our vaccine candidate, hdA5-COVID-19, targets both the nucleocapsid protein on the interior of the virus particle and the spike protein on the virus’ surface.

“We believe this dual targeting is a key advantage that may lead to the stimulation of both T-cell-mediated and antibody-mediated immunity to SARS-CoV-2, which is an important differentiator from other vaccine candidates that only target the spike protein.”

The trial is enrolling 35 healthy participants aged between 18 and 55 years and will take place at the Hoag Hospital in Newport Beach, California, US.

ImmunityBio’s human adenovirus vector, customised to improve its safety and immunogenicity of the Covid insert, showed preliminary safety in over 125 patients in 13 Phase I and II trials till date.

The studies conducted by the National Cancer Institute showed that the Ad5 vector induced antigen-specific T-cell immunity in patients, even in the presence of pre-existing adenoviral immunity.

In the trial, participants will receive hAd5-COVID-19 as a prime and boost dose using the same vector platform to enable sustained protection against SAR-CoV-2.

The goal of the trial is to evaluate the safety and reactogenicity of two doses of the vaccine candidate.

ImmunityBio and NantKwest also plan to develop oral, inhalational and intranasal forms of the vaccine candidate.