The US Food and Drug Administration (FDA) has cleared Altimmune’s Investigational New Drug (IND) application for its Phase I clinical trial of an intranasal Covid-19 vaccine candidate, AdCOVID.

A single-dose vaccine candidate, AdCOVID is designed to trigger a broad immune response including systemic immunity (neutralising antibody), as well as local immunity (mucosal IgA, resident memory T-cells) in the nasal cavity and respiratory tract.

The trial will analyse the safety and immunogenicity of AdCOVID in up to 180 healthy adult participants aged 18 to 55 years.

Subjects will receive AdCOVID at one of three dose levels administered as a nasal spray.

Altimmune anticipates commencement of the patient enrolment in the trial soon.

Apart from primary study endpoint of safety and tolerability, the vaccine candidate’s immunogenicity will be assessed by serum IgG binding and neutralising antibody titers, mucosal IgA antibody from nasal samples and T-cell responses.

Altimmune president and CEO Vipin Garg said: “FDA clearance of the IND marks an important step in developing a safe and effective vaccine designed to stimulate mucosal as well as systemic immunity following intranasal administration.

“Developing vaccines that can effectively prevent transmission is a growing imperative to block the spread of disease and combat the emergence of new variants.”

Preclinical studies carried out in partnership with the University of Alabama at Birmingham, US, showed potent serum neutralising antibody responses, T-cell responses and a strong mucosal immunity induction in mice receiving a single intranasal dose of AdCOVID.

As per data from the company’s other intranasal platform vaccine candidates, AdCOVID potentially has extended stability at room temperature.

This will aid in the vaccine’s cold chain-free shipment and if demonstrated, it could be stored in the common refrigerators for two years or more.

Last November, Altimmune submitted an IND application to the US FDA to start a Phase I clinical study of its Covid-19 vaccine candidate.