Aierkefu Tacrolimus Granules

1. Indications and Usage
Organ Transplantation: Prophylaxis of organ rejection in liver or kidney transplant recipients.
Rescue Therapy: Treatment of graft rejection in liver or kidney transplant recipients unresponsive to other immunosuppressants.
Usage Restrictions: Not indicated for topological dermatitis (distinct from topical tacrolimus preparations).
2. Dosage and Administration
Route of Administration: Oral administration ONLY.
Standard Dosage:
Liver Transplant: Recommended initial dose is 0.1-0.2 mg/kg/day, divided into two equal doses.
Kidney Transplant: Recommended initial dose is 0.15-0.3 mg/kg/day, divided into two equal doses.
Critical Administration Instructions:
Timing: Administer on an empty stomach, either 1 hour before or 2-3 hours after a meal, to ensure consistent absorption.
Monitoring: Dosage must be individualized based on therapeutic drug monitoring (TDM). Target whole blood trough concentrations vary by organ type and post-transplant time.
Administration: Sprinkle the granules onto a small amount of soft food (e.g., applesauce) or mix with water and administer immediately. Do not store for later use.
3. Mechanism of Action
Calcineurin Inhibition: Tacrolimus binds to cytosolic FK506-binding protein 12 (FKBP12).
IL-2 Suppression: This complex inhibits calcineurin phosphatase activity, blocking the dephosphorylation of nuclear factor of activated T-cells (NF-AT). Consequently, it suppresses the transcription of interleukin-2 (IL-2) and other cytokines, inhibiting T-cell activation and proliferation.
4. Safety and Warnings
Nephrotoxicity: Tacrolimus is dose-limiting and can cause acute or chronic renal impairment. Regular monitoring of serum creatinine and renal function is mandatory.
Neurotoxicity: Common manifestations include tremors, headache, insomnia, and paresthesia. Severe cases may involve seizures or posterior reversible encephalopathy syndrome (PRES).
Diabetogenic Effect: May cause beta-cell toxicity leading to new-onset diabetes after transplantation (NODAT) or hyperglycemia.
Infection and Malignancy: High immunosuppression increases susceptibility to bacterial, viral (e.g., CMV, EBV), and fungal infections, as well as lymphoproliferative disorders.
Black Box Warning: May increase susceptibility to infection and the risk of developing malignancies.
5. Adverse Reactions and Clinical Research
Most Common Adverse Reactions: Infection, renal abnormalities, hyperglycemia, diabetes mellitus, hypertension, tremors, headache, paresthesia, and insomnia.
Clinical Research Highlights: Clinical trials have established tacrolimus as a cornerstone in modern transplant medicine, significantly improving graft survival rates compared to historical standards.
6. Drug Interactions
CYP3A4 Inhibitors: Strong inhibitors (e.g., ketoconazole, itraconazole, ritonavir, clarithromycin) significantly increase tacrolimus blood concentrations, raising toxicity risks.
CYP3A4 Inducers: Inducers (e.g., rifampin, phenytoin, carbamazepine, St. John’s Wort) decrease tacrolimus blood concentrations, increasing the risk of rejection.
Nephrotoxic Agents: Concomitant use with aminoglycosides, amphotericin B, or cisplatin increases the risk of nephrotoxicity.
Potassium-Sparing Diuretics: May lead to hyperkalemia.
7. Pharmaceutical Information
Chemical Composition: Active Ingredient: Tacrolimus.
Appearance: White to off-white granules for suspension.
Packaging: Available in various strengths (e.g., 0.5 mg, 1 mg) in sealed bottles or blister packs.
Storage: Store at controlled room temperature, protected from light and moisture.