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
Enfuviritide
Treats HIV Entry inhibitor Binds to gp41 subunit of viral envelope Cannot react with co receptor Subcutaneous injection
Maraviroc
Treats HIV
Entry inhibitor
Binds to host cell membranes CCr5 receptor
Not effective against HIV that targets CXCR4 co receptor
Administration: oral
Raltegravir
Treats HIV
Integrate inhibitor-binds to HIV integrase and blocks the integration of reverse transcribed HIV DNA into host chromosome
Prophylactic treatment effective
