emtricitabine/tdf - Medication Listings

Emtricitabine and tenofovir disoproxil fumarate tablets are fixed-dose combination tablets containing emtricitabine (FTC) and tenofovir disoproxil fumarate (TDF). FTC is a synthetic nucleoside analog of cytidine. TDF is converted in vivo to tenofovir, an acyclic nucleoside phosphonate (nucleotide) analog of adenosine 5'-monophosphate. Both FTC and tenofovir exhibit inhibitory activity against HIV-1 reverse transcriptase. Emtricitabine: The chemical name of FTC is 5-fluoro-1-(2R,5S)-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]cytosine. FTC is the (-) enantiomer of a thio analog of cytidine, which differs from other cytidine analogs in that it has a fluorine in the 5-position. It has a molecular formula of C8H10FN3O3S and a molecular weight of 247.24. It has the following structural formula: [Chemical Structure-1] FTC is a white to off-white powder with a solubility of approximately 112 mg/mL in water at 25°C. The partition coefficient (log p) for emtricitabine is -0.43 and the pKa is 2.65. Tenofovir Disoproxil Fumarate: TDF is a fumaric acid salt of the bis-isopropoxycarbonyloxymethyl ester derivative of tenofovir. The chemical name of tenofovir DF is 9-[(R)-2 [[bis[[(isopropoxycarbonyl)oxy]-methoxy]phosphinyl]methoxy]propyl]adenine fumarate (1:1). It has a molecular formula of C19H30N5O10P • C4H4O4 and a molecular weight of 635.52. It has the following structural formula: [Chemical Structure-2] Tenofovir disoproxil fumarate is a white to off-white, crystalline powder with a solubility of 13.4 mg/mL in water at 25°C. The partition coefficient (log p) for tenofovir disoproxil is 1.25 and the pKa is 3.75. All dosages are expressed in terms of TDF except where otherwise noted. Emtricitabine and tenofovir disoproxil fumarate tablets are for oral administration. Each film-coated tablet contains 200 mg of FTC and 300 mg of TDF (which is equivalent to 245 mg of tenofovir disoproxil), as active ingredients. The tablets also include the following inactive ingredients: microcrystalline cellulose, croscarmellose sodium, lactose monohydrate, pregelatinized starch (gluten free), and magnesium stearate. The tablets are coated with Opadry II White 32K18425, which contains lactose monohydrate, hypromellose 15cP, titanium dioxide, and triacetin.