Melbourne-based Affinity Biosciences Pty Ltd (Affinity), a privately held company focused on antibody discovery for cancer therapeutics, today announces the discovery of potent antibodies with therapeutic potential against COVID-19.

In March, Affinity commenced screening its proprietary library of one hundred billion human antibodies to discover those that might neutralise SARS-CoV-2, the virus that causes COVID-19. After discovering a number of candidate antibodies that block the virus spike protein from binding to its human receptor, Affinity engaged The Peter Doherty Institute for Infection and Immunity (Doherty Institute) in April to conduct testing using the virus in the laboratory. The Doherty Institute has confirmed that Affinity's antibodies can completely neutralise the infectivity of SARS-CoV-2 at a single digit microgram/ml concentration in a five-day virus neutralisation assay. The antibodies have high affinity for the SARS-CoV-2 spike protein at around 20 picomolar, driven by an exceptionally slow off-rate, a measure of how long the antibody remains bound to its target.

"Our antibodies latch onto the virus spike protein and block its activity," said Affinity CEO, Dr Peter Smith. "These antibodies may be protective in humans by preventing the virus from gaining a foothold in healthy people exposed to the virus, and may be useful in arresting the progress of the virus in an infected person by blocking its ability to infect new cells and replicate."

A highly effective therapy would allow faster resumption of normal life by reducing the threat of infected individuals needing hospitalisation.

The next steps in the development of Affinity's COVID-19 therapy are:

Affinity will seek an expedited process to enable their antibodies to be rapidly manufactured to the standards of Good Manufacturing Practice (GMP) for clinical studies.

Identification of expedited clinical development pathways with regulatory agencies (TGA, FDA, and EMA).

Discussions with governments, NGOs, and pharmaceutical companies for accelerated development and commercial distribution. Affinity's antibodies are in a comparative study conducted by the La Jolla Institute for Immunology (the CoVIC program) funded by the COVID-19 Therapeutics Accelerator, launched in March by the Bill & Melinda Gates Foundation, Wellcome Trust, Mastercard, and philanthropists (covic.lji.org).

Affinity is also part of a consortium headed by the Walter and Eliza Hall Institute for the development of biologics against SARS-CoV-2 which recently received funding from the Victorian Government and the Medical Research Future Fund (MRFF).