Promising COVID-19 drug candidate identified by virtual screening

A potential COVID-19 antiviral therapeutic has been identified by researchers following a virtual screening of existing drugs. 

According to the new study, virtually screening compounds to model their interactions with the SARS-CoV-2, the virus causing COVID-19, may not only enable scientists to more easily identify antiviral drugs that work against the virus, but also inform the search for viable vaccine candidates.

Conducted by researchers at Uppsala University, Sweden, the study showed that by screening for interactions with certain structural domains and active sites on the virus, this structure-based approach allowed them to identify existing drugs that can be repurposed, including therapies developed to treat MERS-CoV, SARS-CoV, Ebola, and HIV. They highlight that this approach may also assist with the development of new drugs and protein-based COVID-19 vaccines with fewer experiments and higher reliability than traditional methods.

The researchers say that information about SARS-CoV-2 reported from its recent genome sequencing has revealed key targets for drugs and vaccines, including the Spike (S) protein complex, which helps to mediate viral entry into host cells, as well as the main protease, an enzyme that enables viral replication and transcription. To test how these elements of the virus’ structure may be used to search virtually for prospective drugs, PhD student from Uppsala University Pritam Kumar Panda and colleagues computationally screened 640 antiviral compounds from a database against the S protein and main protease using AutoDock Vina, an open-source programme for identifying the ‘best fit’ orientation of a molecule that binds to a protein.

The researchers then used two additional programs, UCSF Chimera and Discovery Studio Visualizer, to analyse these molecular orientations. The researchers found that an antiviral polymerase inhibitor PC786 targets several SARS-CoV-2 receptors with high affinity, making it a standout among the antiviral drugs they studied.

Panda and the researchers also identified several additional antiviral drugs with strong binding affinities to the S protein and main protease, revealing a number of drugs that may be candidates for further research in efforts to fight COVID-19.

The findings were published in Science Advances.