Coronavirus Puts Drug Repurposing on the Fast Track

Financialnewsmedia.com News Commentary

PALM BEACH, Florida, March 17, 2020 /PRNewswire/ -- Chinese and western biotech companies have been gearing up to repurpose existing drugs, approved in the West for other viruses, as treatments for the coronavirus outbreak originating in Wuhan. Chinese authorities are testing two HIV protease inhibitors (ritonavir and ASC09) in clinical trials to treat COVID-19, the illness caused by the new coronavirus…  and others originally developed to treat Ebola virus and then dropped, will also be tested by private western companies in partnership with Chinesehealth authorities in randomized, controlled trials. "The general genomic layout and the general replication kinetics and the biology of the MERS, SARS and [SARS-CoV-2] viruses are very similar, so testing drugs which target relatively generic parts of these coronaviruses is a logical step," says Vincent Munster, chief, Viral Ecology Unit, US National Institute of Health. Testing therapies approved for other indications also makes senses, as these drugs are already mass produced and available on a large scale.  Active biotech and pharma companies in the markets this week include Moleculin Biotech, Inc. (NASDAQ: MBRX), Moderna, Inc. (NASDAQ: MRNA), Aytu BioScience, Inc. (NASDAQ: AYTU), Inovio Pharmaceuticals, Inc. (NASDAQ: INO), NanoViricides, Inc. (NYSE: NNVC).

"Broad-spectrum agents are ideally suited for outbreak situations where we don't entirely know what we are dealing with in terms of pathogens," says Bryan Mounce, assistant professor, Department of Microbiology and Immunology, Loyola University Chicago. "Although we might not understand all the mechanisms underlying their antiviral activity, it is important that they have as few side effects as possible," he adds.  Most of the drugs in clinical trials inhibit key components of the coronavirus infection lifecycle. These include viral entry into the host cell (blocked by umifenovir, chloroquine or interferon), viral replication (blocked by lopinavir/ritonavir, ASC09 or darunavir/cobicistat, which inhibit the 3C-like protease (3CLpro)) and viral RNA synthesis (inhibited by remdesivir, favipiravir, emtricitabine/tenofovir alafenamide or ribavirin). The genomic secquence of the SARS-CoV-2 suggests that there is a high level of sequence similarity between the SARS-CoV-2, SARS and MERS proteins involved in the replication cycle.