A review: Mechanism of action of antiviral drugs

Abstract

Antiviral drugs are a class of medicines particularly used for the treatment of viral infections. Drugs that combat viral infections are called antiviral drugs. Viruses are among the major pathogenic agents that cause number of serious diseases in humans, animals and plants. Viruses cause many diseases in humans, from self resolving diseases to acute fatal diseases. Developing strategies for the antiviral drugs are focused on two different approaches: Targeting the viruses themselves or the host cell factors. Antiviral drugs that directly target the viruses include the inhibitors of virus attachment, inhibitors of virus entry, uncoating inhibitors, polymerase inhibitors, protease inhibitors, inhibitors of nucleoside and nucleotide reverse transcriptase and the inhibitors of integrase. The inhibitors of protease (ritonavir, atazanavir and darunavir), viral DNA polymerase (acyclovir, tenofovir, valganciclovir and valacyclovir) and of integrase (raltegravir) are listed among the Top 200 Drugs by sales during 2010s. Still no effective antiviral drugs are available for many viral infections. Though, there are a couple of drugs for herpesviruses, many for influenza and some new antiviral drugs for treating hepatitis C infection and HIV. Action mechanism of antiviral drugs consists of its transformation to triphosphate following the viral DNA synthesis inhibition. An analysis of the action mechanism of known antiviral drugs concluded that they can increase the cell’s resistance to a virus (interferons), suppress the virus adsorption in the cell or its diffusion into the cell and its deproteinisation process in the cell (amantadine) along with antimetabolites that causes the inhibition of nucleic acids synthesis. This review will address currently used antiviral drugs, mechanism of action and antiviral agents reported against COVID-19.

Hemin as a novel candidate for treating COVID-19 via heme oxygenase-1 induction

“…Several antiviral therapeutics are currently used for viral infections, and some of them have been found to be effective against COVID-19 2 , 19 . Studies on the antiviral effects of viral RNA polymerase inhibitors (remdesivir/favipiravir), viral protein synthesis inhibitors (ritonavir/lopinavir), inhibitors of viral entry (hydroxychloroquine/chloroquine), and immunomodulators (nitazoxanide/ivermectin) are underway; however, the antiviral effects of HO-1, particularly against SARS-CoV-2, are yet to be investigated thoroughly 19 . HO-1 is known to exhibit cytoprotective and anti-inflammatory activities through its byproducts, and these actions may help modulate inflammation in various diseases 20 .…”

Potential of Marine Terpenoids against SARS-CoV-2: An In Silico Drug Development Approach

“…From SAR analysis, cyclodecene (C 10 H 18 ), cyclohexene oxide (C 6 H 10 O), and γ-butyrolactone or dihydrofuran-2(3H)-one (C 4 H 6 O 2 ) with chlorine in each in all three structures. Indeed, the presence of two methyl butyrate, one methyl acetate with a methyl−like group attachment project many potential drugs and natural products against SARS-CoV-2 with the CADD platform [18,79,[98][99][100]. At present, several tools and databases of bioinformatics are available for gene analysis to vaccine/drug development.…”

“…Generally, terpenoids are more diverse groups of secondary metabolites that exhibited a broad−spectrum inhibition with multiple types of mode of action during the treatment against several diseases [71][72][73][74][75][76]. Most plant and marine terpenoids showed potent antiviral activity in cell lines; however actual mode of inhibition is still under investigation [77][78][79]. Especially, terpenoids showed virucidal activity against the various viruses by Generally, terpenoids are more diverse groups of secondary metabolites that exhibited a broad−spectrum inhibition with multiple types of mode of action during the treatment against several diseases [71][72][73][74][75][76].…”

“…Especially, terpenoids showed virucidal activity against the various viruses by Generally, terpenoids are more diverse groups of secondary metabolites that exhibited a broad−spectrum inhibition with multiple types of mode of action during the treatment against several diseases [71][72][73][74][75][76]. Most plant and marine terpenoids showed potent antiviral activity in cell lines; however actual mode of inhibition is still under investigation [77][78][79]. Especially, terpenoids showed virucidal activity against the various viruses by direct inactivation of free viral particles, avoiding host interaction, induced cell cycle arrest at G0 or G1 phase, and overall target to inhibit viral replication in host-cell [6,80,81].…”

Nanotechnology Applications of Flavonoids for Viral Diseases

“…The foremost thing that can be said of conventional anti-viral drugs is that most viruses and particularly emerging zoonotic viruses do not have suitable drugs or vaccines to effectively fight the various virus-induced diseases. According to a review [11], existing antiviral drugs can be generalized into two classes: drugs targeting the virus itself and drugs targeting host cell factors. A virus needs attachment and subsequent entry into host cells and as such, inhibitors targeting the virus can be compounds that prevent a virus from attaching to the host cell receptor and thus gaining entry into the host cell.…”