France’s Pasteur Institute to develop coronavirus vaccine candidate

Following the rapid surge of the novel coronavirus  infections since January, scientists from all over the world are racing to develop a vaccine against the highly contagious microbe. The Paris-based Pasteur Institute recently submitted its vaccine candidate proposal to Coalition for Epidemic Preparedness Innovations or CEPI.

The Pasteur Institute has submitted a proposal for its coronavirus vaccine candidate. BERTRAND GUAY / AFP

The CEPI is a global alliance that finances and coordinates the development of vaccines.

“Our vaccine candidate uses the measles vaccine as the backbone,” Dr Christiane Gerke, who heads the vaccine programs at the Pasteur Institute told RFI.

French approach

This approach is completely different from the other vaccine candidate proposals. It uses a live-attenuated measles vaccine virus with antigens from SARS-CoV-2 added to it.

Antigens are molecules or proteins present on the surface of the virus that create antibodies in humans and animals to fight against the same microbe.

“The antigens will be selected based on the previous experience of the Pasteur Institute with a measles-based vaccine candidate against SARS which was shown to be efficacious against SARS in mice.”

Researchers at the Pasteur Institute have expertise in the measles vector approach for developing vaccines against another viral disease.

Gerke added: “We have experience with the measles vector in humans. In collaboration with our partner Themis Bioscience, the first of the measles-vectored vaccine candidates, a vaccine candidate against Chikungunya, is entering phase III clinical trials. They have already done safety and immunogenicity trials in many countries.

"Everything looked perfect. The vaccine is very well tolerated and has shown good immunogenicity. So far, I am not aware of measles vector vaccine candidates for infectious disease from other groups that have entered clinical testing,” she says.

Vaccine candidate

Gerke said that if they get the funding from CEPI, they hope the vaccine candidate will be ready in 20 months after completion of all the required clinical testing. This is relatively much faster than the time taken for other diseases.

“When the SARS outbreak occurred (in 2003), it took 20 months for the first vaccine to go into clinical trials, for Zika it took seven, and now with the fastest technologies we are talking four months (for entering clinical trials). Clearly, everyone is learning how to do this quickly. Hopefully, we will be able to address outbreaks much faster than we used to," she added.

However, until a vaccine gets developed, researchers from the world over are trying to find other measures to fight the disease.

According to Gerke, this includes testing antiviral drugs used for other diseases like Flu or Ebola and see if they have any effect in the patients.

“This is the fastest way since they are already licensed for use for other diseases. People are also trying to develop monoclonal antibodies.

"This involves testing the blood from the patients that are recovering and analysing the antibodies they have made. If they find one that is very good at neutralising the virus, it can be produced and can be used as a therapeutic measure,” she says.