Avacc 10 is based on Intravacc’s proprietary outer membrane vesicles (OMV) platform. These spherical particles with immune-stimulating properties can be rigged with immunogenic peptides and/or proteins that stimulate effective adaptive immunity; with the OMV carrier optimized to induce a more effective immune response against these newly introduced antigens.
Furthermore, Intravacc says the OMV platform is scalable and allows rapid and efficient modification of the antigen composition (either through genetic modification of the bacterial host or by associating antigens with stored OMVs).
Intranasal vaccines are a key area research because of their potential capacity to induce local mucosal immunity, thereby targeting the primary route of viral entry of SARS-CoV-2 with the potential of blocking transmission. In addition, intranasal vaccines offer greater practicality in terms of cost and ease of administration.
Pre-clinical data for Avacc 10, published last year, reported ‘very promising’ results: with high levels of spike-binding immunoglobulin G (IgG) and A (IgA) antibodies in the nose and lungs detected in intranasally vaccinated animals (compared to intramuscular vaccination which only induced an IgG response in the serum).
The phase 1 clinical trial, which has commenced at a clinical center in Australia, will assess the tolerability, safety and immunogenicity of the vaccine. In a randomized, double-blind placebo and OMV control study, 36 healthy male and female volunteers aged 18-55, who are IgG seropositive for SARS-CoV-2, will receive two intranasal doses, three weeks apart. One group will receive a low dose and the second group a high dose. Both groups will be followed for a period of 6 months post vaccination.
In addition, the study will evaluate the ability of Avacc 10 to induce an immune response, by measuring IgA and IgG antibodies, neutralizing antibodies, mucosal immunity, and cellular immunity.
The trial will run through June 2023.
For Intravacc, which is located at Utrecht Science Park Bilthoven in the Netherlands, the vaccines represents its launch into a hybrid business model: with a new structure that consists of both CDMO services and a business focused on the development of a proprietary vaccine pipeline.
A key feature of its pipeline is intranasal administration: with other candidates in the pipeline using the OMV tech including the world's first intranasal prophylactic gonorrhea vaccine candidate.
Commenting on the start of the Avacc 10 trial, Dr. Jan Groen, Intravacc’s CEO, said: “This is a very important milestone in the development of our intranasal OMV-based vaccine. We strongly believe that intranasal vaccines offer major advantages over injectable vaccines, and we are excited to take our vaccine concept to the next stage, supporting our CDMO business.”