Tenofovir Disoproxil Fumarate API is the fumarate salt of tenofovir disoproxil, a nucleotide analogue prodrug of tenofovir. It belongs to the nucleotide reverse transcriptase inhibitor (NRTI) class of antiviral agents and is used in pharmaceutical formulations for the management of HIV-1 infection and chronic hepatitis B virus infection.
Tenofovir Disoproxil Fumarate is a 1:1 salt of tenofovir disoproxil and fumaric acid. The API has the molecular formula C₂₃H₃₄N₅O₁₄P and a molecular weight of 635.52 g/mol.
PubChem identifies Tenofovir Disoproxil Fumarate as a fumarate salt prepared from equimolar tenofovir disoproxil and fumaric acid.
Tenofovir disoproxil is a prodrug that is converted in the body to tenofovir and subsequently to the pharmacologically active tenofovir diphosphate. Tenofovir diphosphate inhibits viral reverse transcriptase and DNA polymerase activity.
The API contains a purine nucleoside analogue structure with a phosphonate group protected by disoproxil ester functionality. The fumarate salt provides the pharmaceutical form used in approved drug products.
Tenofovir Disoproxil Fumarate is described as a white to off-white crystalline powder. FDA labeling reports a molecular weight of 635.52 and aqueous solubility of approximately 13.4 mg/mL at 25°C.
Tenofovir Disoproxil Fumarate is used as an antiviral pharmaceutical ingredient in formulations for:
TDF is incorporated into combination products with other antiretroviral agents and has been widely used in HIV treatment. It is also used in appropriate formulations for chronic hepatitis B.
Tenofovir disoproxil fumarate is converted to tenofovir and subsequently phosphorylated intracellularly to tenofovir diphosphate.
Tenofovir diphosphate competes with natural deoxyribonucleotides and is incorporated into viral DNA. Because it lacks the required 3'-OH group for continued DNA elongation, incorporation results in termination of the viral DNA chain.
Through this mechanism, tenofovir diphosphate inhibits HIV-1 reverse transcriptase and hepatitis B virus polymerase activity.
Tenofovir Disoproxil Fumarate is a well-established pharmaceutical API with compendial and WHO-prequalification experience. WHO documentation describes API controls including identification, fumaric acid identification, polymorphic form, melting range, water content, heavy metals, residue on ignition, fumaric acid content, related substances, assay, enantiomeric purity, residual solvents, particle size and bulk density.
Typical quality-control testing includes:
The WHO International Pharmacopoeia framework specifically controls the S-isomer at NMT 0.2% and the mutagenic synthesis-related impurity 9-propenyladenine at NMT 5 ppm in applicable specifications.
Swapnroop Drugs and Pharmaceuticals focuses on quality-oriented pharmaceutical API manufacturing for pharmaceutical development and manufacturing requirements.
For Tenofovir Disoproxil Fumarate, important quality attributes include chemical identity, assay, fumaric acid content, chromatographic purity, enantiomeric purity, polymorphic form, water content, residual solvents and control of process-related impurities.
Tenofovir Disoproxil Fumarate should be packed in suitable pharmaceutical-grade, moisture-protective packaging.
WHO-prequalified API listings specify storage at 2°C to 8°C, protected from moisture and light, for particular approved API products. Packaging may include polyethylene inner bags with a light/moisture barrier and an HDPE outer container.
Commercial storage conditions should always follow the applicable approved specification, stability data and manufacturer's validated packaging configuration.
Depending on customer and regulatory requirements, documentation may include:
Swapnroop Drugs and Pharmaceuticals focuses on quality-oriented pharmaceutical API manufacturing and analytical control.
For Tenofovir Disoproxil Fumarate, emphasis is placed on identity, assay, chromatographic purity, stereochemical quality, fumarate content, polymorphic control, residual solvents, water content and applicable process-related impurities.
Swapnroop Drugs and Pharmaceuticals — quality-focused pharmaceutical API manufacturing from India.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 2.0% |
| Residue on Ignition | NMT 0.20% |
| Heavy Metals | NMT 20 ppm |
| Individual Impurity | NMT 0.10% |
| Water Content | NMT 1.0% |
| Melting Point | Approximately 113–115°C |
| Solubility | Approximately 13.4 mg/mL in water at 25°C |