In search of ways to complement jabs or to treat patients who can’t be vaccinated, scientists have tested inhalable anti-Covid nanobodies on hamsters, saying they’re effective in fighting the virus by targeting its spike protein.
The promising new findings came courtesy of researchers from the University of Pittsburgh School of Medicine, marking the first time nanobodies have been tested for inhalation treatment of the coronavirus disease.
Nanobodies are similar to monoclonal antibodies, widely used in certain cancer treatments, but are smaller in size and boast a lower cost of production, which may prove key to a global rollout should the treatment gain regulatory approval in future.
The researchers previously identified some 8,000 nanobodies which they whittled down to just one highly effective or “ultra potent” version called Nb21, which they then bioengineered to better slot together with the SARS-CoV-2 spike protein.
Their aerosolized nanobody, named Pittsburgh inhalable Nanobody-21 (PiN-21), is said to have reduced the number of infectious virus particles in the test subject hamsters’ nasal cavities, throats and lungs by a million-fold.
“We are very excited and encouraged by our data suggesting that PiN-21 can be highly protective against severe disease and can potentially prevent human-to-human viral transmission,” said co-senior author Yi Shi.
The study says that hamsters who inhaled PiN-21 at the time of infection experienced no Covid-19 related weight loss, compared to the control group, which received a placebo and lost 16% of their initial body weight within a week of infection. This would be the equivalent to an adult human losing 20lbs (9kg) in one week, it said.
Test subjects who inhaled PiN-21 experienced milder changes in lung structure and severely reduced inflammation following infection than the placebo group.
The researchers were careful to emphasize that the nanobodies work in conjunction with but are not a substitute for vaccines. Vaccines help prevent the spread of the virus while the nanobodies help treat those already infected and those who can’t be vaccinated for medical reasons.
Though in its early, preclinical stages, the treatment is said to show significant promise for providing a low-cost therapeutic option to help turn the tide on the global pandemic in humans, though a timeline for human testing has yet to be announced.