| Indications and Usage |
Tenofovir disoproxil (Viread) is the first nucleotide analogue approved by the American FDA to treat HIV-1 infections. Tenofovir disoproxil is a drug used in the AIDS cocktail treatment method, and research shows that it has the ability to increase monkeys’ immunity to immunodeficiency viruses (similar to the human AIDS virus). Tenofovir disoproxil is used in combination with other reverse transcriptase inhibitors to treat HIV-1 infections and hepatitis B. |
| Mechanisms of Action |
Tenofovir disoproxil is an acyclic nucleoside antivirus drug and has an inhibiting effect on HBV multi-enzyme complexes and HIV reverse transcriptase. Its active content tenofovir phosphonate directly competitively binds to natural deoxyribose substrate to inhibit the virus multi-enzyme complex and inserts itself into the DNA to end the nucleotide chain. Tenofovir disoproxil is barely absorbed by the gastrointestinal duct, so it undergoes esterification and ionization to become tenofovir ester fumarate. Tenofovir is soluble in water and can be quickly absorbed and decomposed into the active substance tenofovir, which then transforms into the active metabolite tenofovir phosphonate. As this drug is not metabolized by the CYP450 enzyme system, it has a very low chance of drug interactions caused by this enzyme. |
| Pharmacokinetics |
Tenofovir disoproxil reaches peak blood concentration 1-2 hours after intake. Tenofovir disoproxil’s bioavailability increases by about 40% when taken with food. The intracellular half-life of tenofovir phosphonate is about 10 hours, so doses can be taken once daily. This drug is mainly filtered through renal glomeruli and excreted through the renal tubule transport system, with 70-80% excreted in its original form through urine. |
| Adverse Effects |
- Weakness and exhaustion.
- Mild to moderate gastrointestinal reactions, including diarrhea, stomach pain, nausea, vomiting, bloating, lactic acid poisoning, hepatomegaly and fatty liver, and pancreatitis. These adverse reactions also commonly appear individually or combined when taking nucleoside analogues.
- Metabolic system hypophosphatemia (1% occurrence rate).
- Fat accumulation and redistribution, including centripetal obesity, buffalo hump, thin limbs, breast growth, and Cushing syndrome.
- May cause lactic acid poisoning, hepatomegaly related to steatosis, etc.
- Effects on nervous system: dizziness and headache.
- Effects on respiratory system: difficulty breathing.
- Effects on skin: drug rash.
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| Chemical Properties |
White Crystalline Solid |
| Uses |
Tenofovir is a drug used for the treatment of chronic heptatitis B as well as prevention and treatment of HIV/AIDS. It is a kind of nucleotide analog, acting as the reverse-transcriptase inhibitor (NtRTI). It inhibits the activity of HIV reverse transcriptase through competing with the natural substrate deoxyadenosine 5’-triphosphate, causing the termination of DNA chain. |
| Definition |
ChEBI: A member of the class of phosphonic acids that is methylphosphonic acid in which one of the methyl hydrogens is replaced by a [(2R)-1-(6-amino-9H-purin-9-yl)propan-2-yl]oxy group. An inhibitor of HIV-1 reverse transcriptase, the bis(isopropyloxycarbonyloxy ethyl) ester (disoproxil ester) prodrug is used as the fumaric acid salt in combination therapy for the treatment of HIV infection. |
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