Anti-Viral Flashcards by Michael Bouchard

Herpesvirus

DNA virus - encode on DNA polymerase (target)

Lytic phase - only time to treat

How well did you know this?

Not at all

Perfectly

Drugs to treat Herpesvirus

Acyclovir
Valacyclovir
Foscarnet
Ganciclovir
Valganciclovir
Trifluridine

How well did you know this?

Not at all

Perfectly

MOA Acyclovir

nucleoside analog - requires phosphorylation by viral thymidine kinase
Competitive inhibitor of viral DNA Polymerase - chain termination

How well did you know this?

Not at all

Perfectly

Oral vs IV Acyclovir

Oral - genital herpes, VZV

IV - severe/disseminated, neonatal, HSV encephalitis, VZV in IC

How well did you know this?

Not at all

Perfectly

RES Acyclovir

mutation of thymidine kinase

Cross-resistance with other anti-virals of same mechanism

How well did you know this?

Not at all

Perfectly

AE Acyclovir

mild; come nephrotoxicity and neurotoxicity

How well did you know this?

Not at all

Perfectly

Valacyclovir

prodrug of Acyclovir; metabolized to Acyclovir
3-5x greater bioavailability
Indicated: primary/recurrent genital herpes, varicella in older children/adults, Zoster, orolabial herpes

How well did you know this?

Not at all

Perfectly

MOA Foscarnet

pyrophosphate analog; blocks pyrophosphate release which blocks DNA polymerase
Does not require phosphorylation
Only IV administration

How well did you know this?

Not at all

Perfectly

Indications for Foscarnet

HSV/VZV resistant to Acyclovir

Also: CMV, retinitis, colitis, esophagitis

How well did you know this?

Not at all

Perfectly

AE Foscarnet

renal impairment - avoid nephrotoxic drugs

Blood ion changes

How well did you know this?

Not at all

Perfectly

MOA Ganciclovir

requires phosphorylation by CMV UL97 - competitive inhibitor for DNA polymerase
IV administration; also oral, intraocular

How well did you know this?

Not at all

Perfectly

RES Ganciclovir

mutation of CMV UL97

Cross-resistance with drugs of same mechanism

How well did you know this?

Not at all

Perfectly

Indications for Ganciclovir

CMV retinitis, colitis, pneumonitis, esophagitis

How well did you know this?

Not at all

Perfectly

AE Ganciclovir

Myelosuppression, BM/CNS toxicity, phlebitis, rash

How well did you know this?

Not at all

Perfectly

Valganciclovir

prodrug of Ganciclovir
higher bioavailability
Indicated: CMV retinits, prevention of CMV disease in pts with heart, kidney pancreas transplant

How well did you know this?

Not at all

Perfectly

MOA Trifluridine

requires phosphorylation

competitive inhibitor of thymidine for incorporation into genomes

AE Trifluridine

Low selectivity = avoid systemic administration

Ocular to treat keratoconjunctivitis, keratitis (HSV 1/2)

Influenza

segmented RNA virus from orthomyxovirus family

Serotypes A, B, C - high propensity for mutaiton

MOA Oseltamivir

prodrug - metabolized to active compound by hepatic esterase

Inhibit neuraminidase - inhibit spread of progeny through respiratory tract

RES Oseltamivir

point mutation in hemagglutinin or neuraminidase

Indications for Oseltamivir

> 1
Influenza A/B - given w/in first 48h for uncomplicated
Complicated - give later than 48h

Zanamivir

same as Oseltamivir
Inhaled to oropharynx/lungs
Children >7
AE - lung disturbances; contraindicated in pts with pulmonary disease

Peramivir

Neuraminidase inhibitor
IV administration
Indicated for acute uncomplicated influenza (first 48h)
AE - rash, Steven-Johnson syndrome, hyperglycemia, HTN, CNS

MOA Amantidine/Rimantidine

inhibit influenza A M2 protein - ion channel for nucleocapsid release

Respiratory Syncytial Virus

enveloped RNA virus - paramyxovirus family Most common cause of bronchiolitis/pneumonia in infants, elderly, IC Common cold in adults/older children

MOA Ribavirin

phosphorylated by cellular adenosine kinase interferes with GTP synthesis inhibit viral mRNA cappinginhibit RdRp of RSV and HCV

Administration of Ribavirin

RSV - aerosol HCV - oral in combination Contraindicated in pregnancy, anemia, IVD, RD

AE Ribavirin

hemolytic anemia, depression, fatigue

HCV

RNA virus from flavavirus | Causes hepatitis - inflammation of liver - jaundice, diarrhea, ALT/AST, cirrhosis

HCV Protease inhibitors

"PREVIR"

HCV RNA polymerase inhibitors

"BUVIR"

HCV NS5A Inhibitors

"ASVIR"

Treatment of HCV

combination therapy with DAA | Ribavirin contraindicated in pregnancy

HBV

DNA virus - uses reverse transcriptase Causes hepatitis; chronic correlated with age of infx Chronic infx has HBsAg and anti-HBc without anti-HBc IgM

Pegylated Interferon

Recombinant cytokine - binds Jak/Stat | AE - flu-like SX, AI, neurotoxicity, myelosuppression

Entecavir

Inhibits reverse transcriptase | AE - hematuria, lactic acidosis - not used for HIV

Tenofovir

inhibits reverse transcriptase AE - renal/bone toxicity, Fanconi syndrome, decreased fetal bone density/growth Indicated in chronic Hep B and HIV