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This nucleoside RNA polymerase inhibitor disrupts the viral replication process and has the potential to fight multiple viral threats

Galidesivir (BCX4430) is a broad-spectrum antiviral in advanced development for the treatment of viruses that pose a threat to health and national security, including SARS-CoV-2 (the cause of COVID-19), Ebola, Marburg, Yellow Fever and Zika.

Galidesivir was safe and generally well tolerated in Phase 1 clinical safety and pharmacokinetics trials by both intravenous and intramuscular routes of administration in healthy subjects. In animal studies, galidesivir has demonstrated survival benefits against a variety of serious pathogens, including Ebola, Marburg, Yellow Fever and Zika viruses.

Galidesivir has also demonstrated broad-spectrum activity in vitro against more than 20 ribonucleic acid (RNA) viruses in nine different families, including coronaviruses, filoviruses, togaviruses, bunyaviruses, arenaviruses, paramyxoviruses and flaviviruses.

BioCryst is developing galidesivir in collaboration with U.S. government agencies and other institutions. In September 2013, NIAID contracted with BioCryst for the development of galidesivir as a treatment for Marburg virus disease and potentially for other filoviruses, including Ebola virus

In March 2015, BioCryst announced that the Biomedical Advanced Research and Development Authority (BARDA) within the U.S. Department of Health & Human Services’ Office of the Assistant Secretary for Preparedness and Response (ASPR) has awarded BioCryst a contract for the continued development of galidesivir as a potential treatment for diseases caused by RNA pathogens, including filoviruses.

Galidesivir is an adenosine nucleoside analog that acts to block viral RNA polymerase. RNA polymerase plays a crucial role in the viral replication process, including transcription and replication of the virus genome. Nucleoside RNA polymerase inhibitors, such as galidesivir, are metabolized to the active triphosphate (nucleotide) form by cellular kinases. The drug nucleotide binds to the viral enzyme active site and becomes incorporated into the growing viral RNA strand, leading to premature chain termination.

Interfering with the replication process is a well-established antiviral strategy that has been successfully exploited in developing such life-saving drugs as the nucleoside inhibitors of HIV and acyclovir for herpes simplex complex. This approach could allow a single broad-spectrum drug like galidesivir to address gaps in the U.S. government’s medical countermeasure plan and to possibly replace multiple, pathogen-specific drugs for use in response to both natural outbreaks and bioterrorist threats.

Galidesivir is investigational and has not been deemed safe and effective by the FDA