How it is administered

Temsirolimus is given as an intravenous (IV) infusion. This means it is delivered directly into your vein through a needle, usually over a period of 30 to 60 minutes, once a week. The medication comes as a concentrated solution that must be diluted with a special diluent before being further diluted in saline and administered. Your healthcare team will prepare and give this medication in a clinical setting, such as a hospital or infusion center. Premedication with an antihistamine (like diphenhydramine) is recommended about 30 minutes before each infusion to help prevent allergic reactions.

How it works

Temsirolimus is a type of targeted cancer therapy known as an mTOR inhibitor. The mTOR (mammalian target of rapamycin) pathway is important for cell growth and division. In many cancers, including some blood cancers, this pathway is overactive, leading to uncontrolled cell growth.

Temsirolimus works by binding to a protein inside cells called FKBP-12. This complex then blocks the activity of mTOR, which slows down or stops the growth and division of cancer cells. By interfering with this pathway, temsirolimus can help to halt the progression of cancer. In laboratory studies, blocking mTOR also reduces the production of proteins that help tumors grow new blood vessels, which can further slow cancer growth.

Who Should take it

Temsirolimus is FDA-approved for the treatment of advanced renal cell carcinoma (a type of kidney cancer). However, it is sometimes used off-label for certain blood cancers, including Mantle Cell Lymphoma, especially when other treatments have not worked or are not suitable.

Your doctor may consider temsirolimus if you have a blood cancer that is not responding to standard therapies, or if you have specific reasons why other treatments are not appropriate. The decision to use temsirolimus will depend on your overall health, the type and stage of your cancer, and previous treatments you have received.

Who should not take it

Temsirolimus should not be used in patients with significant liver problems, specifically if your bilirubin level is more than 1.5 times the upper limit of normal. It is also not recommended for people who have had severe allergic reactions to temsirolimus, its metabolites (such as sirolimus), or any of its ingredients.

Caution is needed in people with mild liver impairment, those at risk of infections, or those who are pregnant or breastfeeding. Temsirolimus can cause harm to an unborn baby, so effective contraception is required during treatment and for 3 months after the last dose. Always inform your healthcare team about all your medical conditions and medications before starting temsirolimus.

Commonly used with

Temsirolimus is sometimes used in combination with other cancer treatments, but combining it with certain drugs (like sunitinib) has led to increased side effects and is generally not recommended. It may be used alongside supportive medications such as antihistamines (to prevent allergic reactions), insulin or oral diabetes medications (to manage high blood sugar), and cholesterol-lowering drugs (to manage high cholesterol).

Always discuss with your doctor all the medications you are taking, as temsirolimus can interact with many drugs, including some antibiotics, antifungals, and anti-seizure medications.

Commonly tested with

Temsirolimus has been studied in combination with interferon alfa for kidney cancer, but this combination did not improve survival and increased side effects. In blood cancers, it may be tested with other chemotherapy drugs or targeted therapies in clinical trials, but combinations must be carefully managed due to the risk of increased toxicity.

If you are considering a clinical trial or combination therapy, your healthcare team will review the latest research and your individual situation to determine the best approach.