Last reviewed 2026-04-22 · How we verify

Rapamune® (Sirolimus)

Sirolimus inhibits mTOR (mammalian target of rapamycin), a key signaling protein that controls cell growth and proliferation, thereby suppressing immune cell activation and reducing organ rejection.

Sirolimus inhibits mTOR (mammalian target of rapamycin), a key signaling protein that controls cell growth and proliferation, thereby suppressing immune cell activation and reducing organ rejection. Used for Prophylaxis of organ rejection in patients receiving renal transplants, Lymphangioleiomyomatosis (LAM).

At a glance

Mechanism of action

Sirolimus binds to FKBP12 and the resulting complex inhibits mTOR kinase, which is essential for T-cell and B-cell proliferation. By blocking mTOR, the drug prevents the progression of lymphocytes from the G1 to S phase of the cell cycle, effectively suppressing the immune response. This mechanism makes it particularly useful in preventing organ transplant rejection and treating certain proliferative diseases.

Approved indications

• Prophylaxis of organ rejection in patients receiving renal transplants
• Lymphangioleiomyomatosis (LAM)

Common side effects

• Hyperlipidemia
• Thrombocytopenia
• Anemia
• Hypertension
• Diarrhea
• Headache
• Arthralgia
• Acne
• Impaired wound healing

Key clinical trials

• Comparison of a Contemporary Sirolimus-eluting Stent (ihtDEStiny®) With Another Everolimus-eluting Stent (Xience™), Both With Permanent Polymers, in Patients With Acute Coronary Syndrome and de Novo Coronary Artery Lesions (NA)
• TAPUR: Testing the Use of Food and Drug Administration (FDA) Approved Drugs That Target a Specific Abnormality in a Tumor Gene in People With Advanced Stage Cancer (PHASE2)
• A Study Evaluating the Efficacy and Safety of Multiple Treatment Combinations in Participants With Breast Cancer (PHASE1, PHASE2)
• Ultrathin Strut Sirolimus-eluting Stent With Bioabsorbable Polymer in Patients Receiving Chronic Oral Anticoagulation
• Safety and Effectiveness of the Crystalline Sirolimus-Eluting Device in Patients With Coronary Artery Disease
• Advancing Transplantation Outcomes in Children (PHASE2)
• A Phase I Trial of Combination Gemcitabine and Nab-Sirolimus in Advanced Leiomyosarcomas or Advanced Soft-Tissue Sarcomas With TSC2 or TSC1 Loss-of-function Mutations or Deletions (PHASE1)
• Study to Compare the Efficacy and Safety After Conversion to RaparoBell® or My-Rept® in Kidney Transplant Patients (PHASE4)

Primary sources

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