Nasal coronavirus vaccine in the works

Covid-19 vaccine

A study has shown that nasal delivery produces a more widespread immune response than an intramuscular injection.

Photo credit: Fotosearch

What you need to know:

  • Nasal delivery produces a more widespread immune response than an intramuscular injection.
  • While an injection induces an immune response that prevents pneumonia, it does not prevent infection in the nose and lungs.
  • The coronavirus affects the respiratory tract the most.

You may soon have the option of being vaccinated against Covid-19 through the nose and not via injections.

This is after an Indian vaccine maker announced it is working to deliver a nasal variant of the Covid-19 vaccine. The first and second phases of the trials by Bharat Biotech are expected to begin in two weeks’ time.

Dr Krishna Ella, the founder and chairperson of the pharmaceutical, said the coronavirus also attacks patients through the nose.

“We are working on a nasal vaccine and have partnered with the Washington University School of Medicine. We are working on a single dose vaccine compared to the two-dose inactivated vaccine. Research has proven that the nasal vaccine is the best choice,” she said in a statement.

Bharat Biotech is working to develop two intranasal vaccines; one in conjunction with a US-based vaccine maker FluGen and scientists from the University of Wisconsin Madison while the other is between the pharmaceutical and the University of Washington School of Medicine.

Block infection

Dr Ella said there was compelling scientific evidence to prove that vaccines given through the nasal route were more effective than injected ones. This is because nasal vaccines have faster absorption and lesser volume.

A recent study published in Journal Cell by scientists at Washington University School of Medicine affirmed that nasal delivery produces had a more widespread immune response than an intramuscular injection.

The researchers found the nasal delivery route created a strong immune response throughout the body but was particularly effective in the nose and respiratory tract.

Their findings showed that while the injection induced an immune response that prevented pneumonia, it did not prevent infection in the nose and lungs.

This means that such a vaccine might reduce the severity of Covid-19, but it would not entirely block infection or prevent those infected from spreading the virus.

On the other hand, the nasal delivery route prevented infection in both the upper and lower respiratory tract (the nose and lungs), thereby suggesting that vaccinated individuals would not spread the virus or develop infections elsewhere in the body.

Dr Antony Etyang’, a consultant physician in internal medicine and epidemiology based in Kilifi, said the body had two arms of the immune system. “We have the antibody or protein and cellular immunity,” he told HealthyNation, adding that mucosal immunity is created immediately a nasal vaccine is administered through the nose.

Trojan horse

The coronavirus affects the respiratory tract the most. International experts are of the opinion that nasal vaccines have the potential to become the Trojan horse in the ongoing vaccine race.

Research published by the Frontiers in Immunology journal highlighted that the mucosal immune system is the largest component of immunity, but has not been a focus of much of the Covid-19 research to date. “It is a serious omission to ignore the mucosal immune response to Sars-Cov-2, given its initial sites of infection,” explained Michael Russell, the publisher of the study from the University at Buffalo in America.

Dr Yubrine Moraa, a consultant internist and health advocate in Nairobi, said: “The nose enables immune cells that come into first contact with the virus to have memory not to allow entry of the virus.”

Another nasal vaccine is in the offing in the UK after Medicines and Healthcare Products Regulatory Agency approved Open Orphan and Codagenix to conduct phase one trials of Covi-Vac.

Unlike many other Covid-19 vaccines Covi-vac will also not need a needle, syringe or ultra-cold storage, thereby potentially addressing key logistical concerns by many middle and low income countries like Kenya.