Researchers move a step closer to developing nasal Covid-19 vaccine

Researchers from Lancaster University say they have moved forward towards developing a Covid-19 vaccine which can be taken through the nose.

A pre-clinical study of the intranasal vaccine showed a reduction in both the impact of the disease itself and transmission of the virus.

The vaccine is based on the Newcastle Disease Virus (NDV), a common poultry virus which is able to replicate in humans but is harmless. The team engineered NDV to produce the spike proteins of the SARS-CoV-2 virus which causes Covid-19, tricking the body into mounting an immune response against SARS-CoV-2.

The vaccine induced neutralising antibodies in animals against several novel variants of SARS-CoV-2, raising the possibility of broad protection in vaccinated individuals.

In a study, the team from Lancaster University immunised hamsters with two doses of the vaccine, and saw that the animals displayed complete protection from lung infection, inflammation and pathological lesions following exposure to the SARS-CoV-2 virus.

More so, two doses of the intranasal vaccine significantly reduced the virus shedding from the nose and lungs of the hamsters, indicating that it could help prevent virus transmission and halt the spread of the Covid-19 pandemic.

Being given as a nasal spray could offer advantages such as non-invasive administration and could also be a low-cost alternative for lower-income countries, as it can be scaled up using existing manufacturing infrastructure.

Virologist Dr Muhammad Munir led the study and worked alongside a team of scientists from Lancaster University, in collaboration with researchers from Texas Biomedical Research Institute, USA.

Dr Munir said: “Our studies demonstrate that induction of a local immune response at the point of entry of SARS-CoV-2 has the potential to not only limit clinical disease, but also - and perhaps even more importantly - virus transmission from infected to uninfected individuals.”

While injectable vaccines are offering significant reduction in hospitalisation and death, there is currently no registered intranasal vaccine against Covid-19. Dr Munir said: “After we administered the vaccine into the noses of hamsters and then infected them with SARS-CoV-2, we found almost no virus replication in the lungs and nasal wash of these animals. In contrast, animals given normal NDV showed easily detectable SARS-CoV-2 virus replication in their lungs and nasal washes.”

Professor Jo Rycroft-Malone, Dean of the Faculty of Health and Medicine at Lancaster University, said: “This is an exciting next step in the development of a vaccine for Covid-19 which has the potential to increase the accessibility of a vaccine for people at home and around the world.”

Texas Biomedical Research Institute professor Luis Martinez-Sobrido said: “The hamster animal model developed at Texas Biomed for SARS-CoV-2 studies provided a robust avenue for testing this intranasal vaccine, which is showing promising results. Our study showed that this intranasal vaccine was safe and effective, providing the hamsters protection against SARS-CoV-2.”