Tacrolimus Compounded Oral Suspension

This article is compiled based on the United States Pharmacopeia (USP) – 2025 Edition

Issued and maintained by the United States Pharmacopeial Convention (USP)

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1 DEFINITION

Tacrolimus Compounded Oral Suspension contains NLT 90.0% and NMT 110.0% of the labeled amount of tacrolimus (C₄₄H₆₉NO₁₂).

Prepare Tacrolimus Compounded Oral Suspension 0.5 mg/mL as follows (see Pharmaceutical Compounding—Nonsterile Preparations 〈795〉).

^a Prograf 5-mg capsules, Astellas Pharma US, Inc., Deerfield, IL.

^b Paddock Laboratories, Minneapolis, MN.

Calculate the quantity of each ingredient required for the total amount to be prepared. Empty the required number of Tacrolimus capsules in a suitable mortar. Add the Vehicle in small portions, and triturate to make a smooth paste. Add increasing volumes of the Vehicle to make a tacrolimus liquid that is pourable. Transfer the contents of the mortar, stepwise and quantitatively, to a calibrated bottle. Add enough of the Vehicle to bring to final volume, and mix well. Tacrolimus powder is not interchangeable with Tacrolimus capsules and should not be used.

2 ASSAY

2.1 Procedure

Mobile phase: Acetonitrile and deionized distilled water (65:35). Filter and degas.

Standard stock solution: 0.5 mg/mL of USP Tacrolimus RS in acetonitrile

Standard solution: Pipet 1.0 mL of Standard stock solution into a 10-mL volumetric. flask, and dilute with Mobile phase to volume to obtain a solution having a nominal concentration of 50 μg/mL of tacrolimus. [Note—The Standard solution is relatively unstable, and the Assay should proceed immediately.]

Sample solution: Shake thoroughly by hand each bottle of Oral Suspension. Pipet 1.0 mL of Oral Suspension to a 10-mL volumetric flask, and dilute with Mobile phase to volume to obtain a solution with a nominal concentration of 50 μg/mL of tacrolimus. [Note—The Sample solution is relatively unstable, and the Assay should proceed immediately.]

2.2 Chromatographic system

(See Chromatography 〈621〉, System Suitability.)

Mode: LC

Detector: UV 214 nm

Column: 4.6-mm × 25-cm; 5-μm packing L1

Column temperature: 70°

Flow rate: 1.7 mL/min

Injection volume: 10 μL

2.3 System suitability

Sample: Standard solution

[Note—The retention time for tacrolimus is about 6.4 min.]

2.4 Suitability requirements

Column efficiency: NLT 2500 theoretical plates

Tailing factor: NMT 2.0

Relative standard deviation: NMT 2.0% for replicate injections

2.5 Analysis

Samples: Standard solution and Sample solution

Calculate the percentage of the labeled amount of tacrolimus (C₄₄H₆₉NO₁₂) in the portion of Oral Suspension taken:

Result = (r_U/r_S) × (C_S/C_U) × 100

r_U = peak response from the Sample solution

r_S = peak response from the Standard solution

C_S = concentration of USP Tacrolimus RS in the Standard solution (μg/mL)

C_U = nominal concentration of tacrolimus in the Sample solution (μg/mL)

Acceptance criteria: 90.0%–110.0%

3 SPECIFIC TESTS

pH 〈791〉: 4.1–5.1

4 ADDITIONAL REQUIREMENTS

Packaging and Storage: Package in tight, light-resistant containers. Store at controlled room temperature.

Beyond-Use Date: NMT 90 days after the date on which it was compounded when stored at controlled room temperature

Labeling: Label it to indicate that it is to be well shaken before use, and to state the Beyond-Use Date.

USP Reference Standards 〈11〉

USP Tacrolimus RS