Lesson 3: Anti-viral agents Flashcards
Viral infections in humans and animals are preferably controlled by _______.
immunization
when a vaccine is not available, example for those major viral diseases or emergence of a new virulent strain of virus, this treatment
is necessary.
antiviral chemotherapy
has antiviral activity against influenza A virus by inhibiting an early step in the replication of the virus
Amantadine
anti-influenza drugs
Oseltamivir, Zanamivir & Ribavirin
used against herpesvirus
Acyclovir & Penciclovir
has inhibitory activity against herpesviruses, poxviruses, papillomaviruses and adenoviruses
Famciclovir
active against cytomegalovirus
Ganciclovir
Thymidine Analogue: Ophthalmic solutions used for treating herpesvirus keratitis in animals
Idoxuridine
against herpesvirus, HIV, hepatitis B virus
Foscarnet
used against HIV proteases
Saquinavir, indinavir, ritonavir, nelfinavir, and amprenavir
Peptide analogues of attachment proteins; fusion protein inhibitors; neutralizing antibodies
Attachment to host cell
inhibitors of viral DNA polymerase, RNA polymerase, reverse transcriptase
transcription of viral
genome
Interferons
Assembly of virion components
Neuraminidase inhibitors; specific antibodies plus complement; destruction of infected cells by cytotoxic T cells or NK cells
Release of virions by budding or cell lysis
enhance innate immune responses, indirect antiviral effects
by inducing cytokines prominently interferons
Immunomodulators
mediate the early immune responses to viral infections
Type 1 interferons
produced by mononuclear phagocyte
Interferon-α (IFN-α):
produced by fibroblasts and other cell
Interferon-β (IFN-β)
Is produced by stimulated T cells
and NK cells. It activates macrophages and thereby contribute to the initiation of specific antiviral resistance mediated by antibodies and T
lymphocytes
Type 2 interferon or interferon-Ɣ (IFN-Ɣ)
Example of immunostimulating drugs to viral infections
Imiquimod and Inosine pranobex
prevents virus uncoating shortly after endocytosis of virus by the host cell
Ion-channel blocking compounds
the presence of this drug interfere with the ion channel function of the M2 protein in the nucleocapsid of the virus thus inhibits acid-mediated dissociation of the
ribonucleoprotein complex early in replication, a process essential for
uncoating of the single-stranded RNA genome
amantadine
interfere with release of virus from host cells
Neuraminadase inhibitors
is required to cleave sialic acid from the cell membrane of the
budding virions. Otherwise, persisting sialic acid residues on newly released adjacent virions causes aggregation of the virions on the cell surface
Neuraminidase
Ion channel blockers
Amantadine & Rimantadine
Neuraminadase inhibitors
Oseltamivir & Zanamivir
type of inhibitors used against HIV protease
Protease inhibitors
