This technology includes the design and use of several nanobodies that bind to the SARS-CoV2 spike protein receptor binding domain and block spike protein interaction with the angiotensin converting enzyme 2 (ACE2) receptor. Nanobodies are 12-15 kDa single-domain antibody fragments that are more stable and easier to produce in large quantities compared to conventional antibodies. SARS-CoV2 is the virus responsible for the COVID19 pandemic. The SARS-CoV2 spike protein is responsible for viral entry into human cells via interaction with ACE2 on the cell surface. The nanobodies have therapeutic, preventative, and diagnostic potential. Therapeutics may be delivered via inhalation or intravenously. The lead therapeutic candidate, NIH-CoVnb-112, binds to the SARS-CoV2 spike protein receptor binding domain at approximately 5 nM affinity, and blocks spike protein interaction with the human ACE2 receptor at approximately 0.02 micrograms/mL EC50.
There are currently no effective treatments for SARS-CoV2. However, many therapeutics are currently
in development. Major advantages of SARS-CoV2 nanobody therapeutics over other candidates are high affinity, inhaled route of administration, low cost, and low toxicity.