Antiviral agents
description
Transcript of Antiviral agents
Antiviral agents
Viruses treatable with antiviral drugs HSV VZV CMV HIV Influenza A and B Respiratory syncytial virus (RSV) Hepatitis A, B, and C viruses (HAV;HBV;HCV) Papilloma Picornavirus
Agents active against Herpesviruses-I
Acyclovir Cidofovir Famciclovir and penciclovir Foscarnet Fomivirsen
Agents active against Herpesviruses-II
Ganciclovir Valacyclovir Valganciclovir Vidarabine Topical agents: -Trifluridine
-Vidarabine
Revolution in the field of Infectious diseases: The availability of Increasing number of antiviral agents Against a broadening spectrum of viral
pathogens
Mechanism of action of antiviral agents
is essential , for appropriate clinical use and for understanding and managing antiviral
resistance !
Acyclovir
HSV encephalitis Neonatal HSV infection Primer genital HSV Mucosal and cutaneous HSV-1 and HSV-2
infections in immunocompromised patients VZV infection Recurrent genital herpes
Acyclovir resistance
Mutation either in viral TK or DNA polymerase genes.
Cidofovir
Broad activity:
-adenoviruses
-herpesviruses
-papovaviruses
-poxviruses
Cidofovir
Prophylaxis and treatment of CMV retinitis in patients with AIDS
Acyclovir and foscarnet resistent HSV infections
Famciclovir and Penciclovir
DNA polimerase inhibitor Nucleoside analogue Famciclovir: synthetic Active metobolite: penciclovir 1% topical penciclovir
Famciclovir
Singles (acute zoster) Genital HSV Mucocutaneous HSV in HIV infected
patients
Foscarnet
Pyrophosphate analogue DNA polymerase inhibitor RT inhibitor Active agains all herpesviruses, HIV, HBV
Foscarnet
CMV retinitis in AIDS patients Acyclovir resistant mucuccutaneous HSV
infections in AIDS patients Gancyclovir resistant CMV pulmoner
infections in AIDS patients Acyclovir resistant VZV infections in AIDS
patients
Fomivirsen
Inhibits viral replication by antisense mechanism: its a nucleotide sequence which is complementary to a sequence in mRNA transkript and translation is inhibited.
Intravitreal injection for CMV retinitis
Ganciclovir
Guanoside analogue DNA polimerase inhibitor Similar to acyclovir i.v, oral and intraocular application
Ganciclovir
Prevention and treatment of CMV retinitis in AIDS patients CMV disease in transplant patients
Valacyclovir
Active metobolite= acyclovir
Vidarabine
Nucleosid analogue First licensed systemic antiviral agent Acyclovir has supplanted vidarabine
Topical agents for HSV keratitis
Trifluridine Vidarabine
Interferons
Low molecular weight proteins With complex antiviral, immunomodulating, antiproliferative
activities. Produced by eucaryotic cells in response to various
inducers: viruses 3 types: IFN-, IFN-β , INF- δ IFN-2b: widest application Pegilated- IFN-polyethyleneglycol to the
interferon, through a process known as pegylation, enhances the half-life of the interferon when compared to its native form.
HIV(Human immunodeficeincy virus) Nucleoside analogue reverse transcriptase
inhibitors:Zidovudine (azidothymidine) Non- Nucleoside analogue reverse
transcriptase inhibitors Protease inhibitors Fusion inhibitors Integrase inhibitors
Hepatitis C: Interferon-ribavirin Hepatitis B: INF-lamivudine (reverse
transcriptase inhibitor), adefovir, … Papillomavirus: Interferon- RSV: Ribavirin CMV:ganciclovir, foscarnet VZV: valacyclovir, famciclovir Picornavirus: pleconaril
Anti-influenza drugs
1. Influenza A: Amantadine Rimantadine2. Influenza A and B Zanamivir: enzyme inhibitors of neurominidase,
virus release is inhibited. Oseltamavir: the same The length of disease is reduced if taken within
the first 48hours