Published in the peer-reviewed journal Science Advances, the paper said intranasal delivery of PiN-21 at 0.6 mg/kg protects infected animals (Syrian hamsters) from weight loss and substantially reduces viral burdens in both lower and upper airways. The researchers said that their therapy could provide a convenient and low-cost option to mitigate the ongoing pandemic.
Notably, they added, PiN-21 aerosols can be inhaled to target respiratory infection that drastically reduces viral loads and prevents lung damage and viral pneumonia.
To assess the efficacy of PiN-21, twelve hamsters were divided into two groups and infected with the coronavirus via the intratracheal route. Shortly after infection, the nanobody was delivered intranasally at an average dose of 0.6 mg/kg. The scientists then monitored the animals daily for weight change and symptoms of the disease. The hamsters showed rapid weight loss, up to 16% of their initial body weight, after a week of infection. However, concurrent delivery of PiN-21 through the nose eliminated any significant weight loss in the infected animals.
“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,” Yi Shi, the paper’s co-senior author and assistant professor of cell biology at the University of Pittsburgh, told Science Daily website.
The researchers added that nanobodies and vaccines are not aimed at competing with one another and they can complement each other. Vaccines can prevent new cases, but nanobodies can be used to treat those who already are sick and those who can’t get vaccinated for other medical reasons.
“COVID-19 is now a preeminent disease of the 21st century. Delivering the treatment directly to the lungs can make a big difference for our ability to treat it,” Doug Reed, the study co-author and associate professor of immunology at the varsity, told the website.