Flashcards in Lecture 11: Chemotherapeutics (Part 2): Anti-Viral Drugs Deck (88)
Viruses are ________, intracellular _________ (i.e. they must live within cells)
t/f: large and deceptively simple
f: Small and deceptively simple
Viruses depend on the ________ _______of the host for ________ and ________/___________
t/f: Developing drugs that follow selective toxicity can be difficult (toxic to the virus, not host)
Some viruses have different _______ than host cells.
Drug therapy directed against __________ enzymes
allows greater _______ with less host _______
Viral infection and replication occur in cells in distinct steps.
Drugs may interfere with these steps to be more _______ for the virus cells than host cells
t/f: herpes family are all RNA viruses
f: all DNA viruses
herpes simplex 1: location
oral-facial including ocular (most common)
herpes simplex 2: location
genital and ocular (less common)
herpes simplex 1 vs. 2: distinguishably in the eye?
in the eye clinically indistinguishable
Varicella-Zoster Virus: 2 types - name them.
Human herpesvirus 6a, 6b, & 7
Kaposi’s sarcoma-associated herpesvirus
Drugs to Treat HSV (1+2) and VZV:3
t/f: acyclovir, valacyclovir, famciclovir have a strong activity against Epstein Barr Virus (EBV), cytomegalovirus (CMV), and HHV-6
when do you ideally want to start acyclovir, valacyclovir, and famciclovir
72 hrs of symptom onset
MOA for acyclovir, valacyclovir, famciclovir
All inhibit viral DNA synthesis selectively by inhibiting the viral enzyme DNA polymerase
Acyclovir, Valacyclovir, and Famciclovir are ________ _________ __________
Guanine Nucleoside Analogues
Guanine Nucleoside Analogues are drugs made to do what?
trick infected cells by the virus by disguising themselves as nucleosides.
active drug: _________
Bioavailability of acyclovir ____% - needs dosed ____ frequently (__X/day)
Bioavailability of valacyclovir ____% - dosed ____ frequently than acyclovir (__X/day)
Bioavailability of famciclovir ____% - dosed _____ as valacyclovir (3X/day)
Bioavailability of acyclovir 22% - needs dosed more frequently (5X/day)
Bioavailability of valacyclovir 55% - dosed less frequently than acyclovir (3X/day)
Bioavailability of famciclovir 80% - dosed same as valacyclovir (3X/day)
Acyclovir, Valacyclovir, Famciclovir are activated (_____________) initially by virus-specific ______ ________
Acyclovir, Valacyclovir, Famciclovir requires what?
viral kinase for initial phosphorylation
it is only activated in infected cells (selective toxicity), not in uninfected host cells
t/f: Acyclovir, Valacyclovir, Famciclovir are not well tolerated?
f: well-tolerated, few systemic adverse effects
Adverse Effects Anti-HSV and VZV Drugs
2. GI disturbances
3. Rare, anti-viral induced crystalline nephropathy
4. Rare, CNS symptoms: agitation, hallucinations confusion, encephalopathy in elderly
CMV infections occur primarily in advanced _____________(_____ or on _________ that suppress the immune system)
(AIDS or on medications that suppress the immune system)
Dissemination of CMV infection results in end-organ disease including (5) CCREP
4. CNS disease
Although the incidence of CMV reactivation in HIV-infected patients has markedly decreased with the advent of ________ drug therapy, clinical reactivation of CMV infection after organ transplantation is still prevalent
antiretroviral drug therapy
Drugs to Treat CMV: 4
1. ganciclovir: also topical for HSV
2. valganciclovir: prodrug of ganciclovir