Afinitor

Cancer Treatment

Afinitor is used to treat specific types of advanced cancer, including:

• Breast Cancer: It is used for advanced hormone receptor-positive, HER2-negative breast cancer in postmenopausal women. It is typically given along with another medicine called exemestane after other treatments have been tried.
• Neuroendocrine Tumors (NET): It is used for certain types of tumors in the pancreas, lungs, or digestive tract that are progressing and cannot be removed by surgery.
• Kidney Cancer: It is used to treat advanced renal cell carcinoma (RCC) in patients whose cancer has progressed after treatment with other specific medications.

Tuberous Sclerosis Complex (TSC)

Afinitor is also used to treat conditions caused by tuberous sclerosis complex, a genetic disorder that causes non-cancerous tumors to grow in the body:

• Brain Tumors: It is used for subependymal giant cell astrocytoma (SEGA) in adults and children when the tumor cannot be fully removed by surgery.
• Kidney Tumors: It is used for renal angiomyolipoma, a type of kidney tumor associated with TSC, when immediate surgery is not required.
• Seizures: It is used as an additional treatment for partial-onset seizures associated with TSC in both adults and children.

Mechanism of Action

Afinitor belongs to a class of medications known as mTOR inhibitors. It works by targeting a specific protein called mammalian target of rapamycin (mTOR), which acts as a control center for cell growth, division, and survival.

In many types of cancer and certain genetic conditions, the mTOR pathway becomes overactive. This causes cells to multiply too quickly and survive longer than they should. Afinitor interferes with this process in the following ways:

• Inhibiting Cell Division: By binding to the mTOR protein, the drug blocks the signals that tell cells to grow and replicate. This helps slow down the spread of cancer cells or the growth of non-cancerous tumors.
• Restricting Blood Flow: The medication helps reduce the production of vascular endothelial growth factor (VEGF), a substance that triggers the growth of new blood vessels. By limiting the blood supply, the drug starves the tumor of the oxygen and nutrients it needs to grow.
• Managing Genetic Conditions: In conditions like tuberous sclerosis complex (TSC), genetic mutations cause the mTOR pathway to be constantly active. Afinitor helps regulate this pathway, which can lead to the shrinking of specific types of tumors associated with the condition.

Common Side Effects

• Mouth sores or ulcers
• Skin rash, itching, or dry skin
• Feeling tired or weak
• Diarrhea, nausea, or vomiting
• Loss of appetite and weight loss
• Cough or cold-like symptoms
• Swelling in the hands, ankles, or feet
• Headache or fever
• Irregular menstrual periods
• Changes in taste

Serious Side Effects

Some side effects can be severe and require immediate medical attention. Contact a healthcare provider right away if you experience:

• Lung problems: New or worsening cough, chest pain, or shortness of breath, which may indicate inflammation of the lungs.
• Infections: Signs of infection such as fever, chills, or skin redness, as the drug can weaken the immune system.
• Kidney issues: Decreased urination or swelling in the lower legs.
• High blood sugar: Increased thirst, frequent urination, or blurred vision.
• Wound healing: Slow-healing wounds or incisions.
• Blood cell changes: Unusual bruising, bleeding, or extreme paleness.
• Severe allergic reactions: Swelling of the face, lips, tongue, or throat (angioedema).

Serious Lung Problems

Non-infectious pneumonitis is a significant risk associated with this medication. This condition involves inflammation of the lungs that is not caused by an infection. Symptoms may include a new or worsening cough, shortness of breath, or chest pain. In some cases, this condition can be fatal.

Infections

Afinitor can suppress the immune system, increasing the risk of developing serious bacterial, fungal, viral, or protozoal infections. Some of these infections may be life-threatening. Healthcare providers typically monitor for signs of infection and may prescribe preventative treatments.

Angioedema and Hypersensitivity

Serious allergic reactions, including anaphylaxis, have occurred. There is also an increased risk of angioedema, which causes swelling of the face, lips, tongue, or throat. This risk may be higher for individuals taking ACE inhibitors for high blood pressure.

Mouth Sores and Inflammation

Stomatitis, which includes mouth sores and inflammation of the lining of the mouth, is a very common side effect. Specific mouthwashes or topical treatments may be recommended to manage these symptoms.

Kidney and Metabolic Changes

This medication may affect kidney function and has been linked to cases of kidney failure. It can also cause significant increases in blood sugar levels and blood fats, such as cholesterol and triglycerides. Regular blood tests are usually performed to monitor these levels.

Wound Healing and Surgery

Afinitor can interfere with the body's ability to heal wounds. It is typically stopped for a period before and after elective surgeries to reduce the risk of complications.

Blood Cell Counts

Treatment may lead to decreased levels of red blood cells (anemia), white blood cells (neutropenia), and platelets (thrombocytopenia). These changes can increase the risk of fatigue, infection, and bruising or bleeding.

Pregnancy and Fertility

This drug can cause harm to a developing fetus. Effective birth control should be used during treatment and for a period after the last dose. It may also affect fertility in both men and women.

Vaccinations

Live vaccines should be avoided during treatment with Afinitor, as the weakened immune system may not respond safely to the vaccine.

Pregnancy

Afinitor can cause harm to a fetus if taken during pregnancy. Animal studies have shown that the medication may lead to developmental issues or pregnancy loss. It is important to inform a healthcare provider if you are pregnant or planning to become pregnant before starting this medication.

Effective birth control is necessary during treatment:

• Females: Those who can become pregnant should use highly effective contraception while taking Afinitor and for 8 weeks after the final dose.
• Males: Men with female partners who can become pregnant should use effective contraception during treatment and for 4 weeks after the final dose.

Breastfeeding

It is currently unknown if Afinitor passes into human breast milk. Because of the potential for serious side effects in a nursing infant, breastfeeding is not recommended during treatment and for at least 2 weeks after the last dose.

Fertility

This medication may affect fertility in both men and women, which could impact the ability to conceive a child. Patients should discuss these risks with their healthcare team.

Afinitor is supplied in two distinct oral formulations:

• Oral Tablets: These are standard tablets intended to be swallowed whole with water.
• Tablets for Oral Suspension: Known as Afinitor Disperz, these tablets are designed to be dissolved in water to create a liquid suspension before administration.

These two forms of the medication are not interchangeable. The tablets for oral suspension are prepared differently and are absorbed by the body differently than the standard oral tablets. Patients should use only the specific form that has been prescribed for them.

FDA Approval and Indications

Afinitor was first approved by the U.S. Food and Drug Administration (FDA) in 2009. It is currently approved for the treatment of several specific conditions:

• Breast Cancer: Used in combination with exemestane for postmenopausal women with advanced hormone receptor-positive, HER2-negative breast cancer.
• Neuroendocrine Tumors (NET): Used for adults with progressive tumors of pancreatic origin, as well as certain types of lung or gastrointestinal origin that cannot be removed by surgery.
• Renal Cell Carcinoma: Used for advanced kidney cancer when other treatments have not worked.
• Tuberous Sclerosis Complex (TSC): Used for specific tumors including subependymal giant cell astrocytoma (SEGA) and renal angiomyolipoma, as well as for certain types of seizures associated with TSC.

Regulatory Oversight and Safety Monitoring

The FDA continues to monitor the safety of Afinitor through the FDA Adverse Event Reporting System (FAERS). This system identifies potential signals of serious risks or new safety information. When a signal is identified, the FDA evaluates the data to decide if regulatory action, such as updating the drug's labeling or issuing a safety communication, is required.

Afinitor is classified as a kinase inhibitor, specifically an mTOR inhibitor. While it is approved for several indications, its use must be managed by a healthcare professional experienced in the use of anticancer therapies.

Factors Affecting Cost

The price of Afinitor can vary significantly based on the following:

• Insurance Coverage: Most insurance plans, including Medicare and Medicaid, provide coverage for Afinitor, but out-of-pocket costs like copays or coinsurance will vary depending on the specific plan.
• Generic Availability: A generic version of Afinitor, called everolimus, is available and is generally less expensive than the brand-name drug.
• Pharmacy Type: Because Afinitor is a specialty medication, it is often dispensed through specialty pharmacies rather than standard retail pharmacies, which may affect how the drug is billed.

Financial Assistance

Patients who are prescribed Afinitor may have access to financial support options to help manage out-of-pocket expenses:

• Manufacturer Programs: The drug manufacturer may offer copay cards or patient assistance programs to help reduce costs for eligible individuals with commercial insurance or those who are uninsured.
• Support Organizations: Some non-profit organizations provide grants or assistance for medications used to treat cancer or certain genetic conditions.

It is recommended to contact your insurance provider and the specialty pharmacy to get an accurate estimate of your specific costs and to inquire about available assistance programs.