Antiviral Drugs Flashcards
Sofosbuvir (Sovaldi)
MOA: nucleotide analog inhibits viral RNA polymerase
Prodrug nepucleoside metabolized to nucleotide triphosphate (active form)
Combo with ribavirin or interferon
Expensive
Treats hep C
Simeprevir (Olysio)
MOA: protease inhibitors, prevents viral maturation
Combo with ribavrin or interferon
Expensive
Treats hep C
Acyclovir
Guanosine analog
Spectrum: herpes, Epstein Barr, CMV
Mechanism: selective viral kinase, mono phosphate cellular kinases
Decrease G for DNA leads to chain termination
Absorption: GI or topical
Distribution: CSF
Termination: renal excretion
Toxicity: mild GI upset, headache , renal toxicity
Gancyclovir
Guanosine nucleoside analog,
DNA chain terminator
Spectrum: herpes CMV
Toxicity: bone marrow suppression, CNS, teratogenic
Iododeoxyuridine
Thymidine analog Spectrum: DNA viruses, herpes Mechanism: decrease viral DNA synthesis And incorporated into DNA Affects mammalian DNA too Topical administration
Vidarabine
Adenosine analog
Spectrum: DNA virsuses
Sometimes used with acyclovir
Mechanism: not clear, metabolized to the nucleotide triphosphate
Competes with adenine nucleotides and incorporated leading to chain termination
Decrease viral DNA synthesis
Amantidine
Specific for influenza A-treats and prophylactic
Mechanism: inhibits M2 proton channel mediating influx of H+ releasing the viral nucleotide-blocks uncoating
Absorption: oral
Termination: renal
Toxicity: GI upset and CNS, nervous light headed, difficultly concentrating
High levels of resistance
Oseltamivir
Specific for influenza A and amantidine resistant Treats and prevents Induces conformational change of neuraminidase, cleaving sialic acid residues necessary for release of viral particles Virus accumulates at cell surface Absorption: oral Termination: renal excretion Toxicity:mild GI upset Resistance can occur
Zanamivir
Treat and prevent influenza A and B
Inhibits viral neuraminidase without a conformational change
Less resistance
Absorption: intranasal delivery or dry powder inhalation
Renal excretion
Toxicity: well tolerated some wheezing and bronchospasm
Interferons
Treat and prevent hep B and C
Block penetration, uncoating RNA and DNA synthesis
MOA: inhibit transcription, translation, mRNA splicing, initiation or mRNA translation, tRNA, post translational processing, virus maturation, and virus release
Alpha: used most recombinant, beta: produced by cells, gamma: stimulate t lymphocytes
IV administration
Toxicity: chills, fever, headache, depress bone marrow, confusion, behavior chances
Lamivudine
Treats Hep B
Cytidine analog metabolized to trinphosphate
MOA: inhibitor of DNA polymerase and reverse transcriptase (HIV) chain terminator
Absorption: GI tract distributes to TBW
Renal excretion
Some liver toxicity-mild
Zidovudine (AZT)
Treats HIV
Thymidine analog- a N=N+=N instead of a hydroxyl group (= are triple bonds)
Reverse transcriptase inhibitor-terminates DNA replication
Absorption: oral
Termination: metabolism by liver-renal excretion
Toxicity: fatigue, nausea, headache, anemia
Nevirapine
Treats HIV
Non nucleoside reverse transcriptase inhibitor
Absorption: oral
Toxicity: rash, fever, fatigue, nausea, liver toxicity
Efavirenz
Treats HIV
Non nucleoside reverse transcriptase inhibitor Absorption: oral
CNS: impaired concentration, abnormal dreams, headache, dizziness, rash
Some must stop use due to side effects
Use when resistant to AZT
Atazanavir and indinavir
Treats HIV
Protease inhibitors-block viral maturation
Inhibitors of cytochrome P450 mediated drug metabolism
Inhibit metabolism of many drugs-adjustment of dose may be needed
