The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to threaten public health worldwide. The development of effective therapies to combat coronavirus disease (COVID-19) is urgently needed. Neutralizing antibodies (nAbs) have great potential for the prevention and treatment of SARS-CoV-2 infection.

At the Bioprocess Research and Development Unit (UDIBI), in collaboration with GlobalBio Inc., we have isolated and characterized several antibodies with therapeutic potential for the treatment of COVID-19. This progress achieved is due to our experience in the development of antibodies for diagnostic purposes, linked with the discovery and optimization of therapeutic antibodies for other indications (TNF, PD1 and others).

For the isolation of nAbs we constructed semi-synthetic single-chain variable fragment or scFv libraries, called ALTHEA Gold Plus LibrariesTM. Using the receptor binding domain (RBD) of SARS CoV-2 as selector, we obtained a set of antibodies that block ACE2-RBD binding and neutralize the virus. We are currently improving the affinity of these antibodies obtaining 3 leading candidates with high neutralizing potential.