Cocrystal Pharma has announced the selection of two investigational antiviral drug candidates, CDI-988 and CDI-873, to further develop them as oral therapies to treat Covid-19.
The new broad-spectrum oral candidates act on a conserved area in the active site of SARS-CoV-2 main (3CL) protease needed for replication of the viral ribonucleic acid (RNA).
Cocrystal intends to commence a first-in-human clinical trial of one of the candidates soon this year.
CDI-988 and CDI-873 are chemically distinct but both demonstrated greater in vitro potency against the SARS-CoV-2 virus, retaining activity against present variants of concern including Omicron.
Developed using the structure-based antiviral drug discovery platform of Cocrystal, the candidates showed a favourable safety profile, as well as pharmacokinetic properties that aid in daily oral dosing, in preclinical studies.
Cocrystal had obtained the US Food and Drug Administration (FDA) guidance this month for its pre-Investigational New Drug (IND) briefing package to further advance CDI-45205, a protease inhibitor.
The response of the regulatory agency clarifies the path for a planned Phase I trial and offers guidance for a Phase II trial subsequently, the company noted.
In 2020, Cocrystal obtained CDI-45205 through an exclusive licence agreement with the Kansas State University Research Foundation in the US.
Cocrystal Pharma president and interim co-CEO Sam Lee said: “We plan to continue evaluating both CDI-988 and CDI-873 for clinical development, while we are also rapidly advancing our inhalation/pulmonary SARS-CoV-2 lead candidate CDI-45205 toward clinical development.
“The objective of our multipronged strategy is to offer highly potent and safe antiviral therapeutics for hospitalised patients, as well as for those not requiring hospitalisation, including for prophylactic use to provide protection to uninfected individuals who may become exposed.”