A unique type of tiny antibodies produced by llamas has “significant potential” as a new Covid-19 treatment by using them in a simple nasal spray, a study published in the Nature scientific journal reveals.
The research, led by scientists at the Rosalind Franklin Institute, showed that nanobodies (a smaller, simple form of antibody generated by llamas and camels) can effectively target the SARS-CoV-2 virus that causes Covid-19.
“Nanobodies have a number of advantages over human antibodies,” said Professor Ray Owens, head of protein production at the Rosalind Franklin Institute and lead author of the research.
“They are cheaper to produce and can be delivered directly to the airways through a nebuliser or nasal spray, so can be self-administered at home rather than needing an injection,” he added.
Such a spray would be far easier for patients to use and also gets the treatment directly to the infection site in the respiratory tract, Owens explained.
The researchers were able to generate the nanobodies by injecting a portion of the virus’ spike protein (which binds it to human cells so it can infect them) into a llama called Fifi, who is part of the antibody production facility at the University of Reading.
The injections did not make Fifi sick but they triggered her immune system to fight the virus protein by generating nanobodies against it. A small blood sample was then taken from Fifi, from which the researchers were able to purify four nanobodies.
The nanobodies bind tightly to the virus and neutralise it in cell culture, which could provide a cheaper and more convenient alternative to human antibodies taken from patients who have recovered from Covid-19; while human antibodies have been a key treatment, they must be administered via an intravenous (IV) line in hospital.
According to Public Health England, the research has “significant potential” for both the prevention and treatment of Covid-19 and the nanobodies “are among the most effective SARS-CoV-2 neutralising agents we have ever tested.”
“While vaccines have proven extraordinarily successful, not everyone responds to vaccination and immunity can wane in individuals at different times,” said Professor James Naismith, Director of the Rosalind Franklin Institute.
“Having medications that can treat the virus is still going to be very important, particularly as not all of the world is being vaccinated at the same speed and there remains a risk of new variants capable of bypassing vaccine immunity emerging,” he added.
If successful and approved, nanobodies could provide an important treatment around the world as they are easier to produce than human antibodies and don’t need to be stored in cold storage facilities, stressed Naismith.
As a next step, the research team, which included scientists at the University of Liverpool, University of Oxford and Public Health England, hope to get funding so they can carry out further research to prepare for clinical studies in humans.