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Sirolimus (SIR)

H. Lee Moffitt Cancer Center and Research Institute · FDA-approved active Small molecule

Sirolimus inhibits mTOR (mammalian target of rapamycin), a key signaling protein that controls cell growth and proliferation.

Sirolimus inhibits mTOR (mammalian target of rapamycin), a key signaling protein that controls cell growth and proliferation. Used for Prevention of organ rejection in transplant recipients, Various cancers with mTOR pathway activation (investigational).

At a glance

Generic nameSirolimus (SIR)
Also known asRapamune
SponsorH. Lee Moffitt Cancer Center and Research Institute
Drug classmTOR inhibitor
TargetmTOR (mammalian target of rapamycin)
ModalitySmall molecule
Therapeutic areaOncology; Immunology
PhaseFDA-approved

Mechanism of action

Sirolimus binds to FKBP12 and forms a complex that inhibits mTOR kinase activity, suppressing cell cycle progression and reducing protein synthesis. This mechanism makes it useful as an immunosuppressant and anti-cancer agent by blocking proliferation of T cells and tumor cells. It is particularly effective in preventing organ rejection and has activity in certain cancers driven by mTOR pathway activation.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results