Term
| At what CD4+ Tcell count should an Asymptomatic HIV infected person be offered treatment? When should a Symptomatic HIV infected person be treated? |
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Definition
Aymptomatic >200 but <350cells/uL
Symptomatic Treat at any value |
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Term
| What are the Benefits and Risks of Deferring Anti-HIV treatment? |
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Definition
Benefits:
Avoid negative effects on quality of life
Avoid drug related toxicity
Preserve future drug options
Delay Drug resistance
Decrease total time on Medications
Risks:
Possible irreversible immune system depletion
Increased possibility of progression to AIDS
Possible increased risk of HIV transmission |
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Term
| What are the Fusion Inhibitor Anti-HIV drugs? |
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Definition
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Term
| Which fusion inhibitor binds to gp41? |
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Definition
Enfuvirtide
Binds gp41 of the viral envelope -> prevents conformational change and impedes the fusion of the viral and host cell membranes |
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Term
| What type of resistance can develop with Enfuvirtide? |
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Definition
| gp41 mutations may develop when drug given at suboptimal doses as monotherapy |
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Term
| Why does Enfuvirtide have to be administered subcutaneously? |
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Definition
| Made up of 36 amino acid synthetic peptide |
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Term
| What Fusion Inhibitor has an increased risk of bacterial pneumonia? |
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Definition
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Term
| What are the Nucleoside Reverse Transcriptase Inhibitors? |
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Definition
Didanosine
Lamivudine
Zidovudine
Combinations:
Combivir (AZT+3TC)
Trizivir (AZT+3TC+Abacavir) |
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Term
| What is the Mechanism of Action of the NRTIs? |
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Definition
Analogs of naturally occurring nucleosides
Competitive inhibitor of viral reverse transcriptase -> Once Binds -> DNA chain termination |
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Term
| What NRTIs are analogs of pyrimidine nucleoside (T)? |
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Definition
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Term
| What NRTIs are analogs of pyrimidine nucleoside (C)? |
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Definition
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Term
| What NRTI is an analog of purine nucleosides (A,G)? |
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Definition
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Term
| What NRTI is the only one shown to reduce perinatal HIV transmission? |
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Definition
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Term
| What general pharmacological properties do the NRTIs have? |
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Definition
Good oral absorption
Poor binding to plasma proteins
Metabolism does not rely on cytochrome P-450 system
Excreted unchanged in urine except, Zidovudine |
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Term
| What NRTI is metabolized to glucoronide? |
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Definition
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Term
| Which NRTI is acid labile? How should it be taken? |
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Definition
Didanosine
Take 1/2h before or 2h after meals |
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Term
| What Common toxicities do the NRTIs have? What drug has a higher incidence in some? |
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Definition
GI distress
Lactic acidosis with hepatic steatosis
(higher incidence with stavudine)
Lipodystrophy
(higher incidence with stavudine) |
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Term
| What NRTI can cause Bone Marrow suppression? |
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Definition
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Term
| What NRTI can cause diarrhea, peripheral neuropathy, pancreatitis? |
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Definition
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Term
| What drugs should be avoided with Zidovudine? |
|
Definition
Drugs that are bone marrow suppressive
Ganciclovir
interferon alpha
dapsone
flucytosine
vincristine
vinblastine |
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Term
| What drugs should be avoided with Didanosine? why? |
|
Definition
Augment neuropathy and pancreatitis
Ethambutol
isoniazid
vincristine
cis-platin
Increases Plasma conc 2x
Ganciclovir
Decreases Plasma levels:
Methadone |
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Term
| What NRTI's plasma concentration is increased by trimethoprim-sulfamethoxazole? |
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Definition
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Term
| What are the Protease Inhibitors? |
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Definition
|
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Term
| What is the most effect group of ARTs available? |
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Definition
|
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Term
| What are Protease Inhibitors effective for? |
|
Definition
in both acutely and chronic HIV-1 infected cells
in monocytes and macrophages
(Early stages of HIV-1 replicaion cycle not affected) |
|
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Term
| What is the mechanism of Action of the Protease Inhibitors? |
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Definition
Selective, competitive inhibitors of HIV proteases
Bind reversibly to protease active site
Prevent cleavage of polyprotein and block viral maturation |
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Term
| What PIs have an increased plasma concentration if taken with a meal? |
|
Definition
Increased:
Saquinavir (600%)
Ritonavir (15%)
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Term
| What PI is a potent inhibitor of CYP3A4 and can be used to increase plasma conc of other PIs? |
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Definition
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Term
| Which PIs have autoinduction of metabolism? |
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Definition
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Term
| Are dose adjustments needed for renal dysfunction when using PIs? |
|
Definition
| No, Renal excretion is minimal |
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Term
| How does Ketoconazole effect PIs? |
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Definition
| upregulates PIs (adjust dose) |
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Term
| What drugs AUC is augmented by PIs? |
|
Definition
Sildenafil (Viagra)
(PIs inhibit metabolism of Sildenafil -> increasing plasma conc.) |
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|
Term
| What PIs reduce Methadones AUC? |
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Definition
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Term
| What are the common adverse effects of PIs? |
|
Definition
Hyperlipidemia (more with Ritonavir)
Insulin resistance and diabetes Lipodystrophy
(buffalo hump, protease paunch)
Elevated Liver Function tests
Increased Bleeding risk in hemophiliacs
Drug-Drug interactions |
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Term
| What PI can cause hepatotoxicity at high doses? |
|
Definition
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