Emtricitabine Chemische Eigenschaften,Einsatz,Produktion Methoden
Chemische Eigenschaften
White to Off-White Crystalline Solid
Verwenden
Labeled Emtricitabine, intended for use as an internal standard for the quantification of Emtricitabine by GC- or LC-mass spectrometry.
Definition
ChEBI: An organofluorine compound that is 5-fluorocytosine substituted at the 1 position by a 2-(hydroxymethyl)-1,3-oxathiolan-5-yl group (2R,5S configuration). It is used in combination therapy for the treatment of HIV-1 infect
on.
Acquired resistance
Resistance is associated with a substitution in the HIV-1 reverse
transcriptase gene at codon 184 (M184V/I). Emtricitabineresistant
isolates are cross-resistant to lamivudine. HIV-1 isolates
with the K65R substitution in the reverse transcriptase
coding region have reduced susceptibility.
Allgemeine Beschreibung
Emtricitabine is an orally active NRTI whose pharmacokineticsare favorable for once-daily administration.
Pharmazeutische Anwendungen
A synthetic nucleoside analog of cytosine, formulated for oral use.
Pharmakokinetik
Oral absorption: capsules 93%
C
max 200 mg oral once daily: 1.8 ± 0.7 mg/L
Plasma half-life: c. 10 h
Volume of distribution: 1.4 ± 0.3 L/kg
Plasma protein binding: <4%
Absorption and distribution
It is rapidly and extensively absorbed. There is moderate CNS penetration. The estimated semen:plasma ratio is approximately 4. There are presently no data on levels in breast milk.
Metabolism and excretion
It does not inhibit human cytochrome P
450 enzymes. About 80% is excreted in the urine, the rest in feces. Renal clearance is greater than the estimated creatinine clearance, suggesting elimination by both glomerular filtration and active tubular secretion. There may be competition for elimination with other compounds that are renally excreted. Exposure is significantly increased in renal insufficiency, but dose reductions are not generally recommended. It is unlikely that a dose adjustment would be required in the presence of hepatic impairment.
Clinical Use
Treatment of HIV infection (in combination with other antiretroviral drugs)
Nebenwirkungen
At least 10% of patients suffer headache, diarrhea, nausea,
fatigue, dizziness, depression, insomnia, abnormal dreams,
rash, abdominal pain, asthenia, increased cough and rhinitis.
Skin hyperpigmentation is common (≥10%) in pediatric
patients. Emtricitabine competes with lamivudine for
the enzymes involved in intracellular phosphorylation; their
co-
administration is contraindicated.
Emtricitabine Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
