Neratinib

What is neratinib?

Neratinib is a prescription medicine that is used to treat breast cancer.

Description:

NERLYNX (neratinib) immediate release, film-coated tablets for oral administration contain 40 mg of neratinib, equivalent to 48.31 mg neratinib maleate. Neratinib is a member of the 4-anilino quinolizidine class of protein kinase inhibitors. The molecular formula for neratinib maleate is C 30H 29ClN 6O 3•C 4H 4O 4 and the molecular weight is 673.11 Daltons. The chemical name is (E)-N-{4-[3-chloro-4-(pyridin-2-yl methoxy)anilino]-3-cyano-7-ethoxyquinolin-6-yl}-4-(dimethylamino)but-2-enamide maleate, and its structural formula is:

Neratinib maleate is an off-white to yellow powder with pK as of 7.65 and 4.66. The solubility of neratinib maleate increases dramatically as neratinib becomes protonated at acidic pH. Neratinib maleate is sparingly soluble at pH 1.2 (32.90 mg/mL) and insoluble at approximate pH 5.0 and above (0.08 mg/mL or less).

Inactive ingredients: Tablet Core: colloidal silicon dioxide, mannitol, microcrystalline cellulose, crospovidone, povidone, magnesium stearate, and purified water. Coating: red film coat: polyvinyl alcohol, titanium dioxide, polyethylene glycol, talc, and iron oxide red.

Mechanism of Action

Neratinib is an intracellular kinase inhibitor that irreversibly binds to epidermal growth factor receptor (EGFR), HER2, and HER4. In vitro, neratinib reduces EGFR and HER2 autophosphorylation, downstream MAPK and AKT signaling pathways, and showed antitumor activity in EGFR and/or HER2 expressing carcinoma cell lines. Neratinib human metabolites M3, M6, M7 and M11 inhibited the activity of EGFR, HER2, and HER4 in vitro. In vivo, oral administration of neratinib inhibited tumor growth in mouse xenograft models with tumor cell lines expressing HER2 and EGFR.

Before taking neratinib, tell your doctor:

• If you are allergic to neratinib; any part of this medicine; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
• If you are taking any of these drugs: Dexlansoprazole, esomeprazole, lansoprazole, omeprazole, pantoprazole, or rabeprazole.
• If you take any drugs (prescription or OTC, natural products, vitamins) that must not be taken with neratinib, like certain drugs that are used for HIV, infections, or seizures. There are many drugs that must not be taken with neratinib.
• If you are breast-feeding. Do not breast-feed while you take neratinib or for 1 month after you stop neratinib.

This is not a list of all drugs or health problems that interact with neratinib.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take neratinib with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take neratinib?

• Tell all of your health care providers that you take neratinib. This includes your doctors, nurses, pharmacists, and dentists.
• Sometimes, diarrhea has been severe with neratinib. This has led to other health problems like fluid loss, low blood pressure, and kidney problems.
• You will need to take another drug called loperamide and do other things to help with diarrhea. Follow what your doctor has told you to do. Ask your doctor or pharmacist if you are not sure what to do.
• Have blood work checked as you have been told by the doctor. Talk with the doctor.
• Avoid grapefruit and grapefruit juice.
• If you are 65 or older, use neratinib with care. You could have more side effects.
• This medicine may cause harm to an unborn baby. A pregnancy test will be done before you start neratinib to show that you are NOT pregnant.
• Women must use birth control while taking neratinib and for some time after the last dose. Ask your doctor how long to use birth control. If you get pregnant, call your doctor right away.
• Men with a partner who may get pregnant must use birth control while taking neratinib and for some time after the last dose. Ask your doctor how long to use birth control. If your partner gets pregnant, call the doctor right away.

How is neratinib taken?

Use neratinib as ordered by your doctor. Read all information given to you. Follow all instructions closely.

• Take neratinib with food.
• Take neratinib at the same time of day.
• Swallow whole. Do not chew, break, or crush.
• Drink lots of noncaffeine liquids unless told to drink less liquid by your doctor.
• Take neratinib at least 3 hours after antacids.
• Do not take cimetidine, famotidine, nizatidine, or ranitidine at the same time as neratinib. Take neratinib at least 2 hours before or 10 hours after taking these drugs.
• Keep taking neratinib as you have been told by your doctor or other health care provider, even if you feel well.

What do I do if I miss a dose?

• Skip the missed dose and go back to your normal time.
• Do not take 2 doses at the same time or extra doses.

What are the side effects of neratinib that I need to call my doctor about immediately?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
• Signs of fluid and electrolyte problems like mood changes, confusion, muscle pain or weakness, a heartbeat that does not feel normal, very bad dizziness or passing out, fast heartbeat, more thirst, seizures, feeling very tired or weak, not hungry, unable to pass urine or change in the amount of urine produced, dry mouth, dry eyes, or very bad upset stomach or throwing up.
• Signs of kidney problems like unable to pass urine, change in how much urine is passed, blood in the urine, or a big weight gain.
• Signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
• Signs of a urinary tract infection (UTI) like blood in the urine, burning or pain when passing urine, feeling the need to pass urine often or right away, fever, lower stomach pain, or pelvic pain.
• More than 2 bowel movements in 1 day.
• Swelling of belly.

What are some other side effects of neratinib?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Feeling tired or weak.
• Mouth irritation or mouth sores.
• Muscle spasm.
• Change in nails.
• Dry skin.
• Weight loss.
• Stomach pain.
• Diarrhea, throwing up, upset stomach, and feeling less hungry are common with neratinib. If these happen, talk with your doctor about ways to lower these side effects. Call your doctor right away if any of these effects bother you, do not get better, or get very bad.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

If overdose is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out neratinib?

• Store at room temperature in a dry place. Do not store in a bathroom.
• Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
• Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.