After warnings not to inhale coronavirus droplets, could inhalers be the answer to fighting the pandemic? Scientists at the University of California, San Francisco have developed an aerosol formulation made of antibody-like nanobodies that can prevent the virus from infecting cells.

Self-administered via inhaler or nasal spray, it could be a breakthrough approach to treating coronaviruses while the world waits for a reliable vaccine. [The researchers found that certain nanobodies derived from llamas and camels bind to and neutralize the spike protein found on the exterior of SARS-CoV-2. Synthetic versions of these nanobodies are called AeroNabs. [With once-daily use, AeroNabs can provide strong and reliable protection against SARS-CoV-2 until a vaccine becomes available," the researchers said in a study published in bioRxiv. [Nanobodies are antibody-like immune proteins found in llamas and camels. Because they are much smaller than human antibodies, they are easier to manipulate and modify in the laboratory. Furthermore, unlike human antibodies, nanobodies can be easily and inexpensively mass produced. [9] [10] The UCSF team examined approximately 2 billion synthetic nanobodies to find one that could bind to the SARS-CoV-2 spike protein. In the course of their research, the nanobodies were found to be effective in aerosol form as well, so they could be administered via a storable inhaler or nasal spray.

"We believe that Aeronab, which is much more effective than wearable personal protective equipment, is a molecular form of PPE that could serve as an important stopgap until a vaccine provides a more permanent solution to COVID-19," said Aeronab co-inventor, UCSF biochemistry and biophysics Peter Walter, PhD, professor of biochemistry and biophysics at UCSF and a Howard Hughes Medical Institute research fellow, said.

The inhaler and nasal spray will need to undergo clinical trials before it can be marketed. If these trials are successful, Aeronab will be widely available as an inexpensive over-the-counter drug to prevent and treat COVID-19.