Bacterial vaccines company Intravacc revealed on Tuesday that it has received positive preclinical results for its SARS-CoV-2 Outer Membrane Vesicle (OMV) based recombinant Spike protein (rSp) candidate nose spray vaccine.

Under the company's preclinical study, four groups of mice and four groups of hamsters received two intranasal immunizations on day one and day 21. One group of mice and hamsters received a vaccine based on OMV's mixed with rSp (CovOMV) and the other a vaccine based on OMV's coupled to rSp based on Intravacc's proprietary OMV click technology (CovOMVclick).

According to the company, the mice that received the CovOMV- and CovOMVclick vaccines detected 30% and 90% virus neutralizing antibodies respectively. In all the hamsters both candidate vaccines induced neutralizing antibodies, but the level of antibodies in hamsters that received CovOMVclick was slightly higher compared to the other group.

In addition, the company launched its SARS-CoV-2 intranasal vaccine development programme using its proprietary OMV vaccine technology platform in mid 2020. Its intranasal OMV SARS-CoV-2 vaccine candidates not only induce high mucosal and systemic immune responses, but are a cheap to manufacture and stay stable at 4°C for many years.