Antiviral Drugs Part 2 Flashcards Preview

Microbiology > Antiviral Drugs Part 2 > Flashcards

Flashcards in Antiviral Drugs Part 2 Deck (19):
1

Mechanism - Ganciclovir

Guanosine analog
More active against CMV
5' monophosphate by CMV phosphokinase
Triphosphate by cellular kinases
Inhibits viral DNA poly

2

Clinical uses - Ganciclovir

#1 for CMV retinitis
Disseminated infections - colitis and esophagitis

3

Side effects - ganciclovir

Bone marrow suppression - leukopenia, thrombocytopenia, neutropenia, renal toxicity
MORE TOXIZ THAN ACYCLOVIR

4

Mechanism - Cidofovir

Cytosine analog
No phosphorylation required
Cmv retinitis and HPV & pox virus infections (molluscum contagiosum)
Acyclovir resistant HSV

5

Side effects- cidofovir

Nephrotoxicity

6

Mechanism & clinical use - vidarabine

Arabinose in place of ribose
Phosphorylated by C.K. To triphosphate
Inhibits viral DNA poly
HSV-1 infections ---> encephalitis, keratitis
Less effect and more toxic than acyclovir

7

Mechanism & clinical use - idoxuridine

Iodine atom replaces methyl group of thymidine
Triphosphate by C.K.
Too toxic for systemic used; topical treatment for keratoconjunctivitis
- because formation of faulty progeny DNA and mRNA due to mismatched pairing

8

Mechanism & clinical use - trifluoridine

3 F atoms instead of H atoms on methyl group of thymidine
D.O.C for keratoconjunctivitis; topical use only

9

Mechanism & clinical use - Foscarnet

Pyrophosphate analog
Prevents extension of DNA strand by preventing removal of phosphate from dNTP; inhibits addition of next dNTP
Viral DNA poly inhibition in all herpes viruses
CMV Retinitis and acyclovir resistant mutants of HSV-1 & VZV

10

Side effects - Foscarnet

Nephrotoxicity, electrolyte abnormalities (hypo/hyper kalemia, calcemia, phosphatemia, magnesemia)
Can lead to seizures

11

Inhibitors of retroviruses - nucleoside (7)

Zidovudine
Lamivudine
Stavudine
Abacavir
Tenofovir
Didanosine
Emtricitabine

12

Inhibitors of retroviruses - non nucleoside inhibitors (5)

Delavirdine
Efavirenz
Nevirapine
Etravirine
Rilpivirine

13

Mechanism - NRTIs

Inhibits DNA synthesis by reverse transcriptase of HIV
All are chain terminators
All need to be phosphorylated

14

Zidovudine side effects

Bone marrow suppression (anemia) and myopathy

15

Lamivudine - clinical effects and use & side effects

Reduces viral load and increases CD4 count in combination with ZDV
Used also for chronic Hep B infections
Neutropenia, pancreatitis and peripheral neuropathy

16

Emtricitabine & Didanosine & Stavudine

FTC ---> derivative of 3TC
Prophylaxis pre/postexposure in combination with tenofovir

ddI ---> metabolized to ddATP; those who are intolerant or resistant to ZDV
Pancreatitis and peripheral neuropathy

D4T ---> advanced AIDS, intolerant/resistant to other therapies

17

Abacavir - combination & side effects

Used in combination with a protease inhibitor (Daru/rito) or ZDV+3TC
Side effects ---> liver damage and hypersensitivity reactions in those that have HLA-B*5701 mutation

18

Tenofovir - analog, clinical uses, side effects

Adenosine monophosphate analog
Those who are resistant to other treatment/ those starting treatment
SHOULD be used in combination with other HIV drugs
Side effects---> liver damage, lactic acidosis and renal failure

19

Mechanism, side effects & contraindications- NNRTIs

Do not chain terminate
Do not require phosphorylation
Bind near active site of reverse transcriptase (conformational change)
NOT USED AS MONOTHERAPY; used with NRTIs
Rash and hepatotoxiticity
Vivid dreams and CNS symptoms (dizziness, insomnia, headaches) ---> efavirenz

Delavirdine and efavirenz contraindicated in pregnancy