Antiviral Drugs Flashcards
(23 cards)
Acyclovir & Valacylovir
ACYCLOVIR
Route: PO, IV, Top.
PK: has 3 phosphorylation steps : 1) via viral thymidine kinase - allows drug to be activated in infected cells only; 2/3) via Host cell enzy (Host Kinases)
Viral Spectrum: HSV 1/2, VZV, EBV
MoA: Acycl TriP inhibits viral DNA synth in 2 ways - 1) competitive inhib of viral DNApol, 2) incorporation into viral DNA -> chain termination
Uses: PO -> Genital Herpes (1st episode & recurr infec), Recurr Herpes Labialis, Varicella zoster & Herpes zoster, prophylax of HSV in organ transplant pts; IV -> prophylax of HSV in organ transplant pts, HSV encephalitis, Neonatal HSV
VALACYCLOVIR (Prodrug of Acyclovir) - Greater bioavail
Route: PO
PK: converts to acyc via 1st pass metab. -> greater acyc concen. -> same acyc PK
Viral Spec: HSV 1/2, VZV, EBV
MoA: see acyc
Uses: 1st or Recurr genital herpes
Penciclovir & Famciclovir
PENCICLOVIR (Poor bioavail; only used topically) Routes: Topical PK: see Famcic Viral Spec: see Famcic MoA: see Famcic Uses: Recurr herpes labialis
FAMCICLOVIR (Prodrug of Penciclovir)
Routes: PO
PK: drug activated by phosphorylation via viral thymidine kinase and host cell kinases
Viral Spec: HSV 1/2, VZV, EBV, HBV
MoA: competitive inhib of viral DNApol (lower affinity than acycl, but greater [intracellular]
Uses: Genital herpes, Herpes labialis, acute herpes zoster
Trifluridine
Routes: Ophthal sln
PK: phosphorylated intracellularly by host cell enzy
Viral Spec: HSV 1/2, CMV
MoA: competitive inhib of viral DNA synth by competing with thymidine triphos for incorporation by viral DNApol
Uses: Keratoconjunctivitis, recurr keratitis caused by HSV 1/2
Docosanol
Routes: Topical
Viral Spec: Lipid-enveloped viruses, esp HSV
MoA: inhibits fusion of viral envelope with host cell memb
Uses: Recurr Herpes Labialis
Ganciclovir & Valganciclovir
GANCICLOVIR
Routes: PO; Ophthal
PK: req activation by triphosphorylation - 1st phosphor by viral phosphotransferase in CMV and viral thymidine kinase in HSV
Viral Spec: CMV, HSV, VZV
MoA: Competitively inhibits viral DNApol -> terminates viral DNA elongation
Uses: CMV retinitis, CMV prevention in transplant pts, CMV colitis/esphagitis, Acute Herpetic Keratitis
AE: Neutropenia, Thrombocytopenia; BLACK BOX WARNING
VALGANCICLOVIR (Prodrug to Gancic; greater bioavail)
Routes: PO
PK: Rapid change to Gancic
Viral Spec: CMV, HSV, VZV
MoA: Competitively inhibits viral DNApol -> terminates viral DNA elongation
Uses: CMV retinitis in HIV pts,
AE: BLACK BOX WARNING
Foscarnet
Routes: IV
Viral Spec: CMV, HSV, VZV, HIV 1/2
MoA: inhib of viral DNApol, viral RNApol, HIV RT
Uses: CMV retinitis, colitis, and esophagitis
AE: BLACK BOX WARNING
Cidofovir
Routes: IV - MUST be administered with oral Probenecid (in order to keep therapeutic amnt in blood, must give with Prob., which inhibits excretion of cido to inc its bioavail)
Viral Spec: CMV, HSV 1/2, VZV
MoA: inhibitor of viral DNApol -> inhib DNA synth -> causes chain termination
Uses: CMV retinitis
AE: BLACK BOX WARNING: Renal impairment risk, neutropenia risk
Amantadine
Anti-Influenza Agent
Route: PO
Viral Spec: Influenza A
MoA: blocks M2 proton ion chan of virus and inhibits uncoating of viral RNA w/in infected host cells
Uses: Influenza A; also used in Parkinson’s (w/ diff MoA: stimulates DA release)
Rimantadine
Anti-Influenza Agent Route: PO Viral Spec: Influenza A MoA: blocks M2 proton ion chan of virus and inhibits uncoating of viral RNA w/in infected host cells Uses: Influenza A
Oseltamivar
Anti-Influenza Agent
Route: PO (admin in first 48 hrs)
PK: administered as prodrug and activated by hepatic enzy
Viral Spec: Influenza A & B
MoA: Competitively inhibits viral NA -> blocks release of newly formed viruses from infected host cells -> stops spread
Uses: Influenza A/B; H1N1 (off-label)
Zanamivir
Anti-Influenza Agent
Route: Inhalational (admin in first 48 hrs)
Viral Spec: Influenza A & B
MoA: Competitively inhibits viral NA -> blocks release of newly formed viruses from infected host cells -> stops spread
Uses: Influenza A/B; H1N1 (off-label)
Interferon Alfa
Anti-Hepatitis Agent
Routes: IM, IV, SC
Viral Spec: HBV, HCV, Papillomavirus
MoA: binds to specific cell memb recep -> induces JAK-STAT path -> results in inhib of viral penetration, translation, transcription (tx), maturation, release
Uses: Chronic HBV, Acute/Chronic HCV (adults), Condylomata acuminata (adults)
AE: flu-like synd, fatigue; BLACK BOX WARNING: poss. aggravate fatal neuropsych, autoimmune, ischemic, infectious disorders
C/I: autoimmune hepatitis, cardiac arryth
Adefovir
Anti-HBV Agent
Route: PO
PK: admin as prodrug
Viral Spec: HBV, HIV, Herpes
MoA: competitively inhib HBV RT -> chain termination after incorporation into viral DNA
Uses: Chronic HBV
AE: BLACK BOX WARNING: poss. nephrotoxicity risk, lactic acidosis, hepatomegaly w/ steatosis
Entecavir
Anti-HBV Agent
Route: PO
PK: 100% bioavail; most effective w/ empty stomach
Viral Spec: HBV
MoA: competitively inhib all func of HBV RT
Uses: Chronic HBV
Lamivudine
Anti-HBV Agent
see Heme & Lymph 2
Telbivudine
Anti-HBV Agent
Route: PO
PK: phosphory by cellular kinases to active form
Viral Spec: HBV
MoA: compet. inhib HBV RT -> chain termination
Uses: Chronic HBV
Tenofovir
Anti-HBV Agent
see Heme & Lymph 2
Ribavirin
Anti-HCV Agent
Route: PO
PK: phosphory by host cell enzy to active form
Viral Spec: Influ A/B, Parainflu, RSV, HCV, HIV 1
MoA: not clear; interferes with synth of GTP, which is assoc with capping of viral mRNA, and viral RNA-depen-pol
Uses: Chronic HCV infec, severe RSV bronchiolitis/pneumonia
AE: BLACK BOX WARNING: hemolytic anemia
C/I: Cat X-Preg
Boceprevir
Anti-HCV Agent
Route: PO
Viral Spec: HCV
MoA: inhib HCV NS3/4A protease, which usually cleaves HCV prot into mature forms
Uses: Chronic HCV (give in combo w/ Interferon alfa/Ribavirin
Simeprevir
Anti-HCV Agent
Route: PO
Viral Spec: HCV
MoA: inhib HCV NS3/4A protease, which usually cleaves HCV prot into mature forms
Uses: Chronic HCV (give in combo w/ Sofobuvir/other antivirals
Sofobuvir
Anti-HCV Agent Route: PO PK: admin as prodrug Viral Spec: HCV MoA: compet inhib HCV NS5B RNA-depen RNApol -> blocks viral RNA Rp Uses: Chronic HCV
Palivizumab
Route: IM
Viral Spec: RSV
MoA: works against epitope in A-Ag site on Fusion surface prot of RSV -> neutralizes RSV -> prevents fusion with host cell memb
Uses: RSV prophylaxis
Imiquimod
Route: Topical
MoA: Toll-like recep 7 (TLR7) agonist -> stimulates PMN to release interferon alpha, stimulates MO to make IL 6,8, TNF-alpha -> causes anti-viral effect by resisting all levels of viral Rp
Uses: External genital and perianal warts (HPV)
AE: erythema, erosion, flaking, itching
