SPL Set ID: 5f742224-618e-4f4c-bdec-7693be99c697

Tacrolimus, previously known as FK506, is the active ingredient in tacrolimus capsules. Tacrolimus is a calcineurin-inhibitor immunosuppressant produced by Streptomyces tsukubaensis. Chemically, tacrolimus is designated as (‒)-(3S,4R,5S,8R,9E,12S,14S,15R,16S,18R,19R,26aS)-8-Allyl-5,6,8,11,12,13,14,15,16,17,18,19,24,25,26,26a-hexadecahydro-5,19-dihydroxy-3-[(E)-2-[(1R,3R,4R)-4-hydroxy-3-methoxycyclohexyl]-1-methylvinyl]-14,16-dimethoxy-4,10,12,18-tetramethyl-15,19-epoxy-3H-pyrido[2,1-c][1,4]oxaazacyclotricosine-1,7,20,21(4H,23H)-tetrone monohydrate. The chemical structure of tacrolimus is: Tacrolimus has a molecular formula of C 44 H 69 NO 12 •H 2 O and a formula weight of 822.03. Tacrolimus, USP appears as a white to off-white powder. It is insoluble in water, very soluble in ethanol, and soluble in methanol and chloroform. Tacrolimus capsules, USP are available for oral administration as capsules containing the equivalent of 0.5 mg, 1 mg or 5 mg of anhydrous tacrolimus. Inactive ingredients include anhydrous lactose, black iron oxide, colloidal silicon dioxide, croscarmellose sodium, gelatin, hypromellose, lactose monohydrate, magnesium stearate, sodium lauryl sulfate, titanium dioxide and yellow iron oxide. The 0.5 mg capsules also contain D&C Red No. 28, D&C Yellow No. 10 and FD&C Red No. 40, the 1 mg capsules also contain FD&C Blue No. 1 and FD&C Red No. 3 and the 5 mg capsules also contain D&C Red No. 33, D&C Red No. 28 and D&C Yellow No. 10. In addition, the black imprinting ink contains black iron oxide, D&C Yellow No. 10 Aluminum Lake, FD&C Blue No. 1 Aluminum Lake, FD&C Blue No. 2 Aluminum Lake, FD&C Red No. 40 Aluminum Lake, propylene glycol and shellac glaze. Meets USP Dissolution Test 5. Tacrolimus Structural Formula