Hyftor (Sirolimus)

Sirolimus acts on the mTOR pathway and is employed for several immunologically mediated conditions.

• Tuberous sclerosis complex – facial angiofibromas: reduces size, redness and number of lesions.
• Organ transplantation – prophylaxis of graft rejection: suppresses T‑cell activation to prevent rejection.
• Lymphangioleiomyomatosis: slows disease progression by inhibiting abnormal cell growth.

• Sirolimus binds to the intracellular protein FKBP12, forming a complex that inhibits the mammalian target of rapamycin (mTOR) signaling cascade. This blockade interferes with cytokine‑driven T‑cell proliferation and reduces protein synthesis, leading to immunosuppression and decreased cellular proliferation in targeted tissues.

Sirolimus may cause a range of adverse reactions, varying from mild to severe.

Common Side Effects

• Local skin irritation: redness, itching or burning at the application site.
• Mouth ulcers: painful sores in the oral cavity.
• Hyperlipidaemia: elevated cholesterol or triglyceride levels.
• Headache: mild to moderate intensity.
• Nausea: occasional digestive discomfort.

Serious or Rare Side Effects

• Infections: increased susceptibility to bacterial, viral or fungal infections.
• Pneumonitis: inflammation of lung tissue presenting with cough or shortness of breath.
• Renal impairment: reduced kidney function detectable by laboratory tests.
• Hematologic abnormalities: anemia, leukopenia or thrombocytopenia.

When using Hyftor, consider the following safety measures.

• Monitor blood counts: regular laboratory tests to detect hematologic changes.
• Assess lipid profile: periodic cholesterol and triglyceride measurements.
• Screen for infections: watch for signs of bacterial, viral or fungal disease.
• Evaluate renal function: check serum creatinine and eGFR before and during therapy.
• Avoid use in severe hepatic impairment: dose adjustment may be required.
• Store at below 25°C: keep in the original packaging, protect from moisture and light.

Sirolimus can interact with several drug classes, influencing its concentration and effect.

Major Interactions (Avoid)

• Strong CYP3A4 inhibitors (e.g., ketoconazole, clarithromycin): may cause toxic sirolimus levels.
• CYP3A4 inducers (e.g., rifampicin, carbamazepine): can reduce efficacy by lowering drug exposure.
• P‑glycoprotein inhibitors (e.g., verapamil): increase systemic exposure.

Moderate Interactions (Monitor Closely)

• Anticoagulants (e.g., warfarin): may enhance anticoagulant effect, requiring INR monitoring.
• Statins (e.g., simvastatin, lovastatin): increased risk of myopathy; consider dose reduction or alternative lipid‑lowering agents.
• Vaccines (live attenuated): potential for reduced vaccine efficacy or infection; assess risk‑benefit.