Antivirals/HIV drugs Flashcards Preview

STEP 1 > Antivirals/HIV drugs > Flashcards

Flashcards in Antivirals/HIV drugs Deck (60)
1

Mechanism of oseltamivir/zanamivir

inhibits influenza neuraminidase --> decreased release of progeny virions

2

Use of oseltamivir/zanamivir

treat and prevent both influenza A and B within 72 hrs

3

Mechanism of acyclovir, famciclovir, valacyclovir

guanosine analogs
monophosphorylated by HSV/VZV thymidine kinase and not phosphorylated in uninfected cells --> few adverse effects
triphosphate formed by cellular enzymes
preferentially inhibit viral DNA polymerase by chain termination

4

Use of acyclovir, famciclovir, valacyclovir

HSV - against mucocutaneous and genital lesions and encephalitis
VZV
weak against EBV

prophylaxis in immunocompromised patients
no effect on latent HSV or VZV

5

What do use for herpes zoster?

famciclovir

6

What is special about valacyclovir

prodrug of acyclovir and has better bioavailability

7

Toxicity of acyclovir, famciclovir, valacyclovir

obstructive crystalline nephropathy and acute renal failure if not adequately hydrated

8

Mechanism of resistance of acyclovir, famciclovir, valacyclovir

mutated viral thymidine kinase

9

Mechanism of ganciclovir

5'-monophosphate formed by a CMV viral kinase
guanosine analog
triphosphate formed by cellular kinase
preferentially inhibits viral DNA polymerase by chain termination

10

Use of ganciclovir

CMV, especially in immunocompromised pts

11

What is valganciclovir?

prodrug of ganciclovir with better oral bioavailability

12

Toxicity of ganciclovir

leukopenia, neutropenia, thrombocytopenia, renal toxicity
more toxic to host enzymes than acyclovir

13

Mechanism of resistance of ganciclovir

mutated viral kinase

14

Mechanism of foscarnet

viral DNA/RNA polymerase inhibitor and HIV reverse transcriptase inhibitor
binds to pyrophosphate-binding site on enzyme
NO activation required by viral kinase

15

Use of foscarnet

CMV retinitis in immunocompromised pts when ganciclovir fails
acyclovir-resistant HSV

16

Toxicity of foscarnet

nephrotoxicity, electrolyte abnormalities (hypo- or hypercalcemia, hypo- or hyperphosphatemia, hypokalemia, hypomagnesemia) can lead to seizures

17

Mechanism of resistance of foscarnet

mutated DNA polymerase

18

Mechanism of cidofovir

preferentially inhibits viral DNA polymerase
dose not require phosphorylation by viral kinase

19

Use of cidofovir

CMV retinitis in immunocompromised patients
acyclovir-resistant HSV
long half-life

20

Toxicity of cidofovir

nephrotoxicity (coadminister with probenecid and IV saline to decrease toxicity)

21

What is the standard HART regimen?

2 NRTIs + 1 NNRTI or 1 protease inhibitor or 1 integrase inhibitor

22

Name the protease inhibitors

"-navir"

atazanavir
darunavir
fosamprenavir
indinavir
lopinavir
ritonavir
saquinavir

23

Mechanism of protease inhibitors

assembly of virions depends on HIV-1 protease (pol genes), which cleaves the polypeptide produces of HIV mRNA into their functional parts
thus, protease inhibitors prevent maturation of new viruses

24

Ritonavir and p450

INHIBITS cyt p450

25

Toxicity of protease inhibitors

hyperglycemia
GI intolerance (nausea, diarrhea)
lipodystrophy
neuropathy, hematuria (indinavir)

26

Rifampin and protease inhibitors

rifampin AMPs up the cyt p450 enzymes and thus can lower protease inhibitor concentrations

27

Name the NRTIs

abacavir
didanosine
emtricitabine
lamivudine
stavudine
tenofovir
zidovudine

28

Mechanism of NRTIs

competitively inhibit nucleotide binding to reverse transcriptase and terminates the DNA chain (lack a 3'OH group)

29

Which of the NRTIs is nucleotides?

Tenofovir

30

What do need to do to NRTIs that are nucleosides?

need to be phosphorylated to be active

31

Use of zidovudine

general prophylaxis
PREGNANCY

32

Toxicity of NRITs

bone marrow suppression (give G-CSF and Epo)
peripheral neuropathy
lactic acidosis (nucleoside)
anemia (ZDV)
pancreatitis (didanosine)

33

Name the NNRTIs

Delavirdine
Efavirenz
Nevirapine

34

Mechanism of NNRTIs

bind to reverse transcriptase at site different from NRTIs
do NOT require phosphorylation to be active or compete with nucleotides

35

Toxicity of NNRTIs

rash and hepatotoxicity are common to all

36

Toxicity of efavirenz

rash and hepatotoxicty
vivid dreams and CNS symptoms

37

Contraindication of efavirenz and delavirdine

do NOT use in pregnancy

38

Name the integrase inhibitor

raltegravir

39

Mechanism of integrase inhibitor

inhibits HIV genome integration into host cell chromosome by irreversibly inhibiting HIV integrase

40

Toxicity of integrase inhibitor

increased creatine kinase

41

Mechanism of enfuvirtide

binds gp41, inhibiting viral entry

42

Toxicity of enfuvirtide

skin reaction at injection site

43

Mechanism of maraviroc

binds CCR5 on surface of T cells/monocytes inhibiting interaction with gp120

44

Mechanism of interferons

glycoprotein normally synthesized by virus-infect cells
exhibits antiviral and antihumoral properties

45

Use of interferon-alpha

chronic hepatitis B and C, Kaposi sarcoma, hairy cell leukemia, condyloma acuminatum, renal cell carcinoma, malignant melanoma

46

Use of interferon-beta

multiple sclerosis

47

Use of interferon-gamma

chronic granulomatous disease

48

Toxicity of interferons

neutropenia, myopathy

49

Drugs to treat hepatitis C

ribavirin, simeprevir, sofosbuvir

50

Mechanism of ribavirin

inhibits synthesis of guanine nucleotides by competitely inhibiting inosine monophosphate dehydrogenase

51

Use of ribavirin

chronic HCV, also RSV (palivizumab preferred in children)

52

Toxicity of ribavirin

hemolytic anemia
severe teratogen

53

Mechanism of simeprevir

HCV protease inhibitor
prevents viral replication

54

Use of simeprevir

chronic HCV in combo with ribavirin and peginterferon alfa

55

Can use simeprevir as monotherapy?

NO

56

Toxicity of simeprevir

photosensitivity reactions, rash

57

Mechanism of sofosbuvir

inhibits HCV RNA-dependent RNA polymerase acting as a chain terminator

58

Use of sofosbuvir

chronic HCV in combo with ribavirin +/- peginterferon alfa

59

Can you use sofosbuvir as monotherapy?

NO

60

Toxicity of sofosbuvir

fatigue, headache, nausea