Temsirolimus — Drug Monograph

Brand names: Torisel

Drug class: Other

Mechanism of Action

Temsirolimus is an intravenous ester prodrug of sirolimus and a specific inhibitor of mTORC1 (mechanistic target of rapamycin complex 1). It binds the intracellular protein FKBP-12, and the drug-protein complex inhibits mTORC1 kinase activity, arresting cells in the G1 phase and reducing translation of HIF-1alpha and other proteins that drive angiogenesis (VEGF) and proliferation. This pathway blockade is particularly relevant in renal cell carcinoma, where HIF/VEGF signaling is central to tumor biology.

FDA Indications

• Advanced renal cell carcinoma (RCC)

Common Side Effects

• Rash / maculopapular rash
• Asthenia / fatigue
• Stomatitis / mucositis
• Nausea
• Peripheral and facial edema
• Anorexia
• Hyperglycemia (fasting glucose elevation; mTOR metabolic drift)
• Hyperlipidemia (hypercholesterolemia and hypertriglyceridemia)
• Anemia
• Thrombocytopenia
• Infusion-related hypersensitivity reactions

Clinical Pearl

Temsirolimus is the IV mTORC1 inhibitor for advanced RCC and shares the mTOR-class axes with everolimus — non-infectious pneumonitis (hold + corticosteroid rescue for symptomatic grades) and profound hyperlipidemia/hypertriglyceridemia — plus routine fasting glucose tracking for metabolic drift. Two route-specific distinctions matter at the bedside: (1) mandatory IV antihistamine premedication (e.g., diphenhydramine) ~30 minutes before every weekly infusion to blunt hypersensitivity, which the…

Related Therapies & Mechanisms

• Everolimus (Afinitor) — Other · RCC
• Adagrasib (Krazati) — Other
• Arsenic Trioxide (Trisenox) — Other
• Asparaginase (L-asparaginase, E. coli) (Elspar) — Other