Sirolimus (Rampamycin)

CAS NO: 53123-88-9
Batch Molecular FormulaC51H79NO13
Batch Molecular Weight914.172 g/mol
Physical AppearanceWhite to off white Solid
StorageStore at RT
Batch Molecular Structure

Sirolimus, often marketed under the brand name Rapamune, is a medication with various medical applications. It belongs to a class of drugs known as mTOR inhibitors (mammalian target of rapamycin). Sirolimus works by inhibiting the mTOR pathway, which plays a role in cell growth and proliferation. Here are some of the primary uses of sirolimus:

  1. Immunosuppression: Sirolimus is used as an immunosuppressant medication, particularly in organ transplantation. It helps prevent the body’s immune system from rejecting a transplanted organ, such as a kidney or a liver. It is often used in combination with other immunosuppressive drugs to maintain the transplanted organ’s function.
  2. Cardiac Stents: Sirolimus-eluting stents (drug-eluting stents) are used in cardiology to prevent restenosis (the re-narrowing of blood vessels) following angioplasty and stent placement. These stents slowly release sirolimus to inhibit cell proliferation, reducing the risk of recurrent blockages.
  3. Lymphangioleiomyomatosis (LAM): Sirolimus has been approved for the treatment of lymphangioleiomyomatosis, a rare lung disease that primarily affects women. It can help slow the progression of the disease and improve lung function in some cases.
  4. Other Rare Conditions: Sirolimus is also used in some rare conditions and research settings. It has been investigated for its potential benefits in various diseases, including certain cancers and genetic disorders.

The use of sirolimus should be closely monitored by healthcare professionals, as it can have side effects and interact with other medications. Patients taking sirolimus need regular check-ups and blood tests to ensure that the medication is working effectively and safely. The specific dosage and duration of treatment will vary depending on the medical condition for which it is prescribed.


Sirolimus, also known as rapamycin, is a macrolide compound that is used to coat coronary stents, prevent organ transplant rejection and to treat a rare lung disease called lymphangioleiomyomatosis. It has immunosuppressant functions in humans and is especially useful in preventing the rejection of kidney transplants.