Antiretrovirals Flashcards
(116 cards)
When should you start HIV treatment?
when CD4+ count drops below 500; or in pregnant women, patient with AIDS-defining illness, HBV-HIV co-infection, or nephropathy
MOA of Nucleoside Reverse Transcriptase Inhibitors (NRTIs)
Analogs of native ribosides; lack 3’OH group –> chain termination (act as reversible competitive inhibitors of RT)
Require phosphorylation by cellular enzymes –> incorporated into DNA by RT
Which viruses are NRTIs active against?
HIV-1 and HIV-2
Most common resistance mechanisms of NRTIs
Mutation at viral codon 184
Resistance to which drug restores sensitivity to Zidovudine and Tenofovir?
Lamivudine (Nucleoside/Nucleotide analog used against Hepatic infections)
Which NRTI is especially associated with myelosuppression?
Zidovudine
Which NRTI increases levels of Didanosine? (Drug Interaction)
Tenofovir
AE of NRTIs
inhibition of mitochondrial DNA polymerase ==> peripheral neuropathy, lipoatrophy, myopathy, and lactic acidosis
Pancreatitis, Cardiomyopathy
Which NRTIs are particularly associated with insulin resistance and dyslipidemia?
Zidovudine and Stavudine
What must be monitored while taking NRTIs?
serum creatinine
True or False: NRTIs are metabolized by CYP450 enzymes.
False
Contraindications of Zidovudine
Co-administration with Probenicid, Acetaminophen, Lorazepam, Indomethacin, and Cimetidine;
Since Stavudine and Ribavirin are activated by same pathways as Zidovudine, might reduce active levels of Zidovudine
AE of Zidovudine
Bone marrow suppression, insomnia, insulin-resistance
Thymidine analog (for HIV treatment) that crosses BBB
Zidovudine; doses must be adjusted in patients with cirrhosis
Thymidine analog (for HIV treatment) whose dosage must be adjusted in renal insufficiency
Stavudine
MOA of Stavudine
Strongly inhibits beta and gamma DNA polymerases; has high affinity for mitochondrial DNA polymerase, which can lead to toxicity
PK/PD of Stavudine and Zidovudine
Oral administration
AE of Stavudine
Peripheral neuropathy, lactic acidosis, insulin-resistance, neuromuscular weakness, hyperlipidemia
Adenosine analog (for HIV treatment) that crosses the BBB and penetrates the CSF
Didanosine
Acid labile Antiretroviral best taken with antacid or while fasting
Didanosine
AE of Didanosine
Pancreatitis in alcoholics and patients with hypertriglyceridemia
Which 2 NRTIs have a high affinity for mitochondrial DNA polymerase?
Didanosine and Stavudine
NRTI; Adenosine analog preferred in current regimens (for HIV treatment)
Tenofovir
Fixed dose combinations of Tenofovir
Tenofovir + Emtricitabine & Tenofovir + Emtricitabine + Efavirenz