On March 11, 2020 the World Health Organization (WHO) characterized the novel coronavirus COVID-19 as a pandemic. This announcement followed the rapid worldwide rise of infected individuals determined to be caused by infection with COVID-19.

Coronaviruses (CoV) are a large family of viruses that historically have been associated with illness ranging from mild symptoms similar to the common cold to more severe respiratory disease. Infection with the novel COVID-19 has been associated with a wide range of responses, from no symptoms to more severe disease that includes pneumonia, severe acute respiratory syndrome, kidney failure, and death. The incubation period for COVID-19 is believed to be within 14 days after exposure, with most illness occurring within about 5 days. The ability of someone with no symptoms to transmit infection to another person has heightened the public health challenge of COVID-19.

We are aggressively pursuing the development of novel antiviral compounds for the treatment of coronavirus infections using our established proprietary drug discovery platform. By targeting the viral replication enzymes and protease, we believe it is possible to develop an effective treatment for all coronaviruses causing COVID-19, Severe Acute Respiratory Syndrome (SARS), and Middle East Respiratory Syndrome (MERS).

To learn more about coronavirus, please visit the information page at the Center for Disease Control and Prevention (CDC).

Coronavirus Replication and Protease Inhibitor

Program Discovery Preclinical Phase 1 Phase 2a Phase 2b Phase 3
COVID-19 (Licensed from KSURF) CDI-45205 Protease Inhibitor
Discovery Phase complete
Preclinical Phase in progress
Phase 1 Phase not started
Phase 2a Phase not started
Phase 2b Phase not started
Phase 3 Phase not started
COVID-19 Replication Inhibitors
Discovery Phase in progress
Preclinical Phase not started
Phase 1 Phase not started
Phase 2a Phase not started
Phase 2b Phase not started
Phase 3 Phase not started


In December 2020, we announced the selection of CDI-45205 as our lead coronavirus development candidate among a group of protease inhibitors obtained under an exclusive license agreement with Kansas State University Research Foundation (KSURF).

CDI-45205 showed good bioavailability in mouse and rat pharmacokinetic studies via intraperitoneal injection, and also no cytotoxicity against a variety of human cell lines. We recently demonstrated in vitro a strong synergistic effect with the FDA-approved COVID-19 medicine remdesivir. Additionally, a proof-of-concept animal study demonstrated that daily injection of CDI-45205 exhibited favorable in vivo efficacy in MERS-CoV-2 infected mice. We have obtained promising preliminary pharmacokinetic results and we are continuing to further evaluate CDI-45205.

We are exploring multiple routes of administration of preclinical lead molecules including oral, inhalation and injection. We are also examining in vitro activities of our compounds against the SARS-CoV-2 variants.

Kansas State University Research Foundation (KSURF) licensing agreement

On February 24, 2020 we announced our entry into a license agreement with KSURF to further develop certain proprietary broad-spectrum antiviral compounds for the treatment of norovirus and coronavirus infections. On April 22, 2020 we announced the expansion of the KSURF license agreement to include rights to additional preclinical leads and further develop certain proprietary broad-spectrum antiviral compounds for the treatment of COVID-19.

Under the terms of the agreement, Cocrystal has been granted an exclusive, royalty-bearing right and license to certain small molecule therapeutic inhibitors against coronaviruses, picornaviruses and caliciviruses covered by patent rights controlled by KSURF. This license significantly expanded and further advanced our COVID-19 program by providing more targeted, potent compounds for further development.

Novel SARS-CoV-2 replication inhibitors

We have leveraged our antiviral development expertise by using our proprietary technology and drug discovery platform to launch a second COVID-19 program with additional antiviral compounds developed. We applied our proprietary drug discovery platform technology and high-throughput protein crystallography approach to design new chemical scaffolds to improve in vitro potency and pharmacokinetic properties. Lead discovery and optimization are ongoing. We anticipate identifying another SARS-CoV-2 preclinical lead for oral administration in the second half of 2021. In addition to these two SARS-CoV-2 protease programs, we are also developing novel SARS-CoV-2 inhibitors that block viral replication and transcription.