Nerlynx is a brand-name prescription medication. It’s FDA-approved for the treatment or management of certain types of breast cancer:

  • Early stage HER2-positive (HER2+) breast cancer. Nerlynx helps prevent the return of this type of cancer in adults who’ve previously taken trastuzumab (Herceptin). For this purpose, Nerlynx is used as an adjuvant therapy. This is a treatment used to prevent cancer from returning. (With HER2+ cancer, cancer cells have abnormally high levels of a protein called HER2.)
  • Advanced or metastatic HER2+ breast cancer. Nerlynx is used to treat this type of cancer in adults who’ve already tried two or more other HER2 breast cancer treatments. For this use, Nerlynx is taken with capecitabine (Xeloda). (Metastatic cancer is cancer that has spread to other areas of the body.)

Nerlynx contains the active drug neratinib, which belongs to a class of medications called kinase inhibitors.

Nerlynx comes as a tablet that’s taken by mouth. This drug can be used by both women and men.

FDA approval

The Food and Drug Administration (FDA) first approved Nerlynx in 2017. It was approved for use in adults with early stage HER2+ breast cancer who’ve previously taken trastuzumab (Herceptin).

In 2020, the FDA approved Nerlynx for a second purpose. It was approved for use with capecitabine (Xeloda) to treat HER2+ breast cancer that’s advanced or metastatic in adults who’ve already tried two or more other HER2 breast cancer treatments.

Effectiveness

For information on Nerlynx’s effectiveness, see the “Nerlynx uses” section.

Nerlynx is available only as a brand-name medication. It’s not currently available in generic form.

A generic drug is an exact copy of the active drug in a brand-name medication. Generics tend to cost less than brand-name drugs.

Nerlynx contains the active drug neratinib.

Nerlynx can cause mild or serious side effects. The following lists contain some of the key side effects that may occur while taking Nerlynx. These lists don’t include all possible side effects.

For more information on the possible side effects of Nerlynx, talk with your doctor or pharmacist. They can give you tips on how to deal with any side effects that may be bothersome.

Note: The Food and Drug Administration (FDA) tracks side effects of drugs it has approved. If you would like to report to the FDA a side effect you’ve had with Nerlynx, you can do so through MedWatch.

Mild side effects

The mild side effects of Nerlynx that are more common can include:

  • nausea and vomiting
  • abdominal (belly) pain
  • indigestion (upset stomach)
  • swollen mouth or mouth sores
  • reduced appetite
  • nail problems, including color changes
  • constipation
  • dizziness
  • back pain
  • fatigue (lack of energy)
  • rash (see “Side effect details” below)
  • diarrhea (see “Side effect details” below)

Most of these side effects may go away within a few weeks. But if they become more severe or don’t go away, talk with your doctor or pharmacist.

Serious side effects

Call your doctor right away if you have serious side effects. Call 911 if your symptoms feel life threatening or if you think you’re having a medical emergency.

Serious side effects and their symptoms can include:

  • Severe diarrhea. Symptoms can include:
    • having seven or more additional stools per day than normal
    • not being able to control bowel movements
    • diarrhea that affects your daily activities and ability to care for yourself
    • dehydration (low fluid levels in the body)

Other serious side effects are explained below in “Side effect details.” These include:

Side effect details

You may wonder how often certain side effects occur with this drug, orwhether certain side effects pertain to it. Here’s some detail on several of the side effects this drug may or may not cause.

Allergic reaction

As with most drugs, some people can have an allergic reaction after taking Nerlynx. Symptoms of a mild allergic reaction can include:

  • skin rash
  • itchiness
  • flushing (warmth and redness in your skin)

A more severe allergic reaction is rare but possible. Symptoms of a severe allergic reaction can include:

  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your tongue, mouth, or throat
  • trouble breathing

Call your doctor right away if you have a severe allergic reaction to Nerlynx. Call 911 if your symptoms feel life threatening or if you think you’re having a medical emergency.

Diarrhea

Diarrhea is a common side effect of Nerlynx. In some cases, it can lead to serious complications, such as dehydration or kidney problems.

In two clinical studies, 83% to 95% of people who took Nerlynx experienced diarrhea. This includes the 24% to 40% of people who took Nerlynx and reported severe diarrhea. In comparison, 35% of people who took a placebo (a treatment with no active drug) had diarrhea. Of those taking a placebo, 2% reported severe diarrhea.

Most of the people in the study who had diarrhea experienced it within the first month of their treatment, and it lasted about 3 to 8 days.

To lower your risk for severe diarrhea while taking Nerlynx, your doctor may prescribe you an antidiarrheal drug called loperamide (Imodium).

Call your doctor if you have symptoms of dehydration, such as having a dry mouth or lips or feeling dizzy or weak. Also talk with your doctor if you have more than two bowel movements a day.

Call your doctor right away if you have symptoms of severe diarrhea as described above, or symptoms of dehydration or fever along with diarrhea.

Other digestive problems

Some people may experience digestive problems when taking Nerlynx. In one clinical study, 43% of people taking Nerlynx experienced nausea, compared with 22% of people taking a placebo. Of the people taking Nerlynx, 26% experienced vomiting, compared with 8% of those who took a placebo.

Other digestive problems experienced during the clinical study included:

  • abdominal (belly) pain in 36% of people taking Nerlynx and 15% of those taking a placebo
  • upset stomach in 10% of people taking Nerlynx and 4% of those taking a placebo
  • abdominal swelling in 5% of people taking Nerlynx and 3% of those taking a placebo
  • reduced appetite in 12% of people taking Nerlynx and 3% of those taking a placebo

Talk with your doctor if you’re concerned about digestive problems while taking Nerlynx.

Hair loss

Hair loss wasn’t reported in clinical studies of people taking Nerlynx by itself. However, there have been some reports of hair loss in people taking Nerlynx with other cancer drugs.

Talk with your doctor if you’re concerned about hair loss while taking Nerlynx.

Liver problems

Liver problems may occur while taking Nerlynx. Usually, liver function is measured by lab tests that look at the levels of certain enzymes (proteins) in your blood. These enzymes are called aspartate aminotransferase (AST) and alanine aminotransferase (ALT). A higher level of these enzymes can mean that your liver has been damaged.

In one clinical study, 9% of people taking Nerlynx had raised levels of ALT, compared with 3% of people taking a placebo. In the same study, 7% of people taking Nerlynx had raised AST levels, compared with 3% of those taking a placebo.

Before starting Nerlynx, your doctor will measure your levels of AST and ALT to make sure they can track if there are any increases. They’ll also track your levels of bilirubin and alkaline phosphatase. These are two other blood markers that can show signs of liver damage.

Your doctor will do blood tests every month for the first 3 months of your Nerlynx treatment. After that, you’ll have blood tests done every 3 months.

Symptoms of liver problems can include:

  • fatigue
  • nausea and vomiting
  • tenderness in the upper abdomen
  • fever
  • rash
  • yellowing of the whites of your eyes or your skin

Call your doctor right away if you experience any of these symptoms, as they could be a sign of liver problems.

Rash

Some people may develop a rash while taking Nerlynx. In one clinical study, 18% of people who took Nerlynx developed a rash. In comparison, 9% of people who took a placebo had a rash.

The types of rashes people developed in the clinical studies weren’t always the same. Some people developed acne or pustules (pimples with yellowish pus), while others developed large, itchy rashes.

Call your doctor right away if you develop a rash while taking Nerlynx. This could be a sign of an allergic reaction or liver problems.

The Nerlynx dosage your doctor prescribes will depend on several factors. These include:

  • any side effects that you experience while taking Nerlynx
  • any other medications you may take
  • other medical conditions you may have
  • the severity and type of breast cancer you have

The following information describes dosages that are commonly used or recommended. However, be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.

Drug forms and strengths

Nerlynx comes in 60-mg tablets that are taken by mouth.

Dosage for adjuvant therapy of early stage breast cancer

When used as an adjuvant therapy for early stage HER2-positive (HER2+) breast cancer, the recommended dosage of Nerlynx is 240 mg (six tablets) taken by mouth once a day. Nerlynx should be taken at the same time each day with food for up to 1 year.

(Adjuvant means the treatment is used after you’ve received another treatment, to help prevent your cancer from returning.)

Dosage for advanced or metastatic breast cancer

Nerlynx is used to treat advanced or metastatic HER2+ breast cancer. For this purpose, the recommended dosage of Nerlynx is 240 mg taken by mouth with food once a day on days 1 to 21 of a 21-day treatment cycle. You’ll receive this dose by taking six tablets each day. In addition, capecitabine is taken with Nerlynx on days 1 to 14 of the 21-day cycle.

The number of cycles you complete will depend on how your cancer responds to treatment and whether you experience any side effects.

What if I miss a dose?

If you miss a dose, just skip that dose and take your next scheduled dose as usual. Never take two doses together to make up for a missed dose. This could lead to serious side effects.

To help make sure you don’t miss a dose, try setting a reminder on your phone. A medication timer may be useful, too.

Will I need to use this drug long term?

If you’re using Nerlynx for early stage HER2+ breast cancer, Nerlynx is meant to be used for up to 1 year after you’ve already had treatment with trastuzumab (Herceptin).

If you’re taking Nerlynx with capecitabine to treat HER2+ breast cancer that’s advanced or metastatic, Nerlynx is taken for a 21-day treatment cycle. The number of cycles you complete will depend on how your cancer responds to treatment and whether you experience any side effects. If you and your doctor determine that Nerlynx is safe and effective for you, you may take it long term.

Nerlynx is used to treat early stage HER2-positive (HER2+) breast cancer in adults who’ve previously taken trastuzumab (Herceptin). (With HER2+ cancer, the cancer cells have abnormally high levels of a protein called HER2.) For this purpose, Nerlynx is used as an adjuvant therapy (treatment used to prevent cancer from returning).

Nerlynx is also used to treat HER2+ breast cancer that’s advanced or metastatic (has spread to other areas of the body) in adults who’ve already tried two or more other HER2 breast cancer treatments. For this purpose, Nerlynx is taken with capecitabine (Xeloda).

Nerlynx contains the active drug neratinib, which belongs to a class of drugs called kinase inhibitors. Nerlynx works to kill cancer cells by permanently attaching to cancer cell receptors (docking stations). By attaching to these receptors, Nerlynx can prevent cancer cells from growing. This causes cancer cells to die.

How long does it take to work?

It’s unknown how long it takes Nerlynx to start working in your body, and it’s unlikely that you’ll notice its effects. However, your doctor will perform tests during your treatment to check that the drug is working for you.

There are no known interactions between Nerlynx and alcohol. However, both Nerlynx and alcohol can cause liver damage. Therefore, drinking excessive amounts of alcohol while taking Nerlynx may be harmful to your liver.

If you drink alcohol, talk with your doctor about how much is safe to drink while taking Nerlynx.

Nerlynx can interact with several other medications. It can also interact with certain supplements as well as certain foods.

Different interactions can cause different effects. For instance, some interactions can interfere with how well a drug works. Other interactions can increase side effects or make them more severe.

Nerlynx and other medications

Below is a list of medications that can interact with Nerlynx. This list doesn’t contain all drugs that may interact with Nerlynx.

Before taking Nerlynx, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also tell them about any vitamins, herbs, and supplements you use. Sharing this information can help you avoid potential interactions.

If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.

Certain drugs used for indigestion

Some drugs that treat indigestion (upset stomach) or gastroesophageal reflux disease (GERD) by reducing stomach acid shouldn’t be taken with Nerlynx. Taking these drugs together may lower your body’s ability to absorb Nerlynx. This can result in Nerlynx being less effective at killing cancer cells.

Examples of drugs to completely avoid while taking Nerlynx include:

Examples of drugs that should be taken at least 2 hours after your dose of Nerlynx, or 10 hours before your dose of Nerlynx, include:

  • famotidine (Pepcid, Pepcid AC)
  • cimetidine (Tagamet)
  • nizatidine (Axid)

Examples of drugs that should be taken at least 3 hours before Nerlynx include:

  • calcium carbonate (Tums)
  • bismuth subsalicylate (Pepto-Bismol)
  • aluminum hydroxide (found in products such as Gaviscon and Mylanta)
  • aluminum-magnesium hydroxide (Maalox)
  • calcium carbonate/magnesium hydroxide (Rolaids)
  • magnesium hydroxide (Milk of Magnesia)
  • citric acid/aspirin/sodium bicarbonate (Alka-Seltzer)

Drugs used for certain infections

Some drugs that are used to treat fungal, bacterial, or viral infections interact with an enzyme (protein) in your liver that breaks down Nerlynx. Taking these drugs with Nerlynx can either increase or decrease the level of Nerlynx in your bloodstream. This can raise your risk for side effects or make Nerlynx less effective.

Examples of antifungal drugs that can interact with Nerlynx include:

  • ketoconazole
  • itraconazole (Sporanox)
  • fluconazole (Diflucan)
  • clotrimazole

Examples of antibiotic drugs that can interact with Nerlynx include:

  • clarithromycin
  • erythromycin (Erythrocin)
  • ciprofloxacin (Cipro)

Examples of antiviral drugs that can interact with Nerlynx include:

  • boceprevir
  • ritonavir (Norvir)
  • elvitegravir
  • indinavir (Crixivan)
  • lopinavir/ritonavir (Kaletra)
  • nelfinavir (Viracept)
  • saquinavir (Invirase)
  • tipranavir (Norvir)

Certain drugs used to control blood pressure

Some drugs used to control high blood pressure interact with an enzyme in your liver that breaks down Nerlynx. Taking these drugs with Nerlynx can either increase or decrease the level of Nerlynx in your bloodstream. This can raise your risk for side effects or make Nerlynx less effective.

Examples of these drugs include:

  • diltiazem (Cardizem)
  • verapamil (Calan SR)
  • bosentan (Tracleer)

Drugs used for certain seizure disorders

Some drugs that are used for certain seizure disorders can interact with an enzyme in your liver that breaks down Nerlynx. Taking these drugs with Nerlynx can either increase or decrease the level of Nerlynx in your bloodstream. This can raise your risk for side effects or make Nerlynx less effective.

Examples of these drugs include:

  • phenytoin (Dilantin)
  • carbamazepine (Tegretol)

Nerlynx and herbs and supplements

Nerlynx can interact with the following herbs and supplements. Before starting Nerlynx, talk with your doctor if you take these or any other herbs and supplements.

St. John’s wort

Taking Nerlynx with an herbal supplement called St. John’s wort can decrease the levels of Nerlynx in your body. This can make Nerlynx less effective. To avoid this, you shouldn’t take St. John’s wort during your Nerlynx treatment.

Supplements containing grapefruit juice

Supplements that contain grapefruit can interact with Nerlynx. Grapefruit may increase the levels of Nerlynx in your body, which may raise your risk for side effects. Therefore, you shouldn’t take these supplements during your Nerlynx treatment.

Nerlynx and foods

Nerlynx may interact with certain foods, like grapefruit or grapefruit juice. Eating grapefruit or drinking grapefruit juice while taking Nerlynx may increase the levels of Nerlynx in your body. This may raise your risk for side effects.

Talk with your doctor if you regularly drink grapefruit juice or eat grapefruit.

The Food and Drug Administration (FDA) approves prescription drugs such as Nerlynx to treat certain conditions. Nerlynx may also be used off-label for other conditions. Off-label use is when a drug that’s approved to treat one condition is used to treat a different condition.

For both of its approved uses, Nerlynx can be used by women and men.

Nerlynx for adjuvant therapy of early stage breast cancer

Nerlynx is FDA-approved to treat early stage HER2-positive (HER2+) breast cancer. Nerlynx helps prevent the return of this type of cancer in adults who’ve previously taken trastuzumab (Herceptin).

For this purpose, Nerlynx is used as an adjuvant therapy. This is a treatment used to prevent cancer from returning. (With HER2+ cancer, cancer cells have abnormally high levels of a protein called HER2.)

Effectiveness for adjuvant therapy of early stage breast cancer

A clinical study of Nerlynx involved 2,840 adults with early stage HER2+ breast cancer. Each person had completed treatment with trastuzumab (Herceptin) within the last 2 years.

During the 1-year study, about half of the people received Nerlynx, while the other half received a placebo (a treatment with no active drug). Nerlynx’s effectiveness was measured by looking at invasive disease-free survival. (This refers to the time between starting the drug and either the return of cancer or death for any reason.)

By the end of the study, 94.2% of people taking Nerlynx had reached 2 years of invasive disease-free survival. In comparison, 91.9% of those taking a placebo had reached 2 years of invasive disease-free survival.

Nerlynx for advanced or metastatic breast cancer

Nerlynx is FDA-approved to treat advanced or metastatic HER2+ breast cancer. Nerlynx is used to treat this type of cancer in adults who’ve already tried two or more other HER2 breast cancer treatments.

For this use, Nerlynx is taken with capecitabine (Xeloda). (Metastatic cancer is cancer that has spread to other areas of the body.)

Effectiveness for advanced or metastatic breast cancer

A clinical study involving 621 adults with advanced or metastatic HER2+ breast cancer compared Nerlynx with lapatinib (Tykerb). Both drugs were used with capecitabine (Xeloda). Each person in the study had previously tried at least two other HER2+ breast cancer treatments before starting Nerlynx or lapatinib.

During the 2-year study, about half of the people received Nerlynx, while the other half received lapatinib. People taking either drug received a daily dose on days 1 to 21 days of their 21-day treatment cycle. In addition, each person in the study received capecitabine on days 1 to 14 of their 21-day treatment cycle.

The effectiveness of the drugs was measured by looking at progression-free survival. (This refers to the length of time someone lives without their disease getting worse.)

Of the people who took Nerlynx with capecitabine, half of them experienced progression-free survival for at least 5.6 months. In comparison, half of the people who took lapatinib with capecitabine experienced progression-free survival for at least 5.5 months.

Nerlynx and children

Nerlynx isn’t approved for use in children. It’s not known if Nerlynx is safe or effective for use in children.

For one of its FDA-approved uses, Nerlynx is prescribed with capecitabine (Xeloda). This use is for the treatment of HER2-positive (HER2+) breast cancer that’s advanced or metastatic in adults who’ve tried at least two other breast cancer treatments. (Metastatic cancer is cancer that has spread to other areas of the body.)

And for either of Nerlynx’s approved uses, Nerlynx can be taken with other drugs to lower your risk for side effects.

  • To lower your risk for severe diarrhea while taking Nerlynx, your doctor may prescribe you an antidiarrheal drug called loperamide (Imodium).
  • To lower your risk for vomiting while taking Nerlynx, your doctor may prescribe you an antinausea medication called ondansetron (Zofran) during your Nerlynx treatment.

As with all medications, the cost of Nerlynx can vary. To find current prices for Nerlynx in your area, check out WellRx. The cost you find on WellRx.com is what you may pay without insurance. The actual price you’ll pay depends on your insurance plan, your location, and the pharmacy you use.

It’s important to note that you’ll have to get Nerlynx at a specialty pharmacy. This type of pharmacy is authorized to carry specialty medications. These are drugs that may be expensive or may require help from healthcare professionals to be used safely and effectively.

Your insurance plan may require you to get prior authorization before approving coverage for Nerlynx. This means that your doctor and insurance company will need to communicate about your prescription before the insurance company will cover the drug. The insurance company will review the request and let you and your doctor know if your plan will cover Nerlynx.

If you’re not sure if you’ll need to get prior authorization for Nerlynx, contact your insurance company.

Financial and insurance assistance

If you need financial support to pay for Nerlynx, or if you need help understanding your insurance coverage, help is available.

Puma Biotechnology, Inc., the manufacturer of Nerlynx, offers reimbursement support and supportive care vouchers. For more information and to find out if you’re eligible for support, call 855-816-5421 or visit the program website.

Other drugs are available that can treat your condition. Some may be a better fit for you than others. If you’re interested in finding an alternative to Nerlynx, talk with your doctor. They can tell you about other medications that may work well for you.

Note: Some of the drugs listed here are used off-label to treat these specific conditions. Off-label use is when a drug that’s approved to treat one condition is used to treat a different condition.

Alternatives for adjuvant therapy of early stage breast cancer

Examples of other drugs that may be used as an adjuvant therapy for HER2+ breast cancer include:

  • trastuzumab (Herceptin)
  • pertuzumab (Perjeta)
  • bevacizumab (Avastin)
  • letrozole (Femara)
  • paclitaxel
  • docetaxel (Taxotere)

Alternatives for advanced or metastatic breast cancer

Examples of other drugs that may be used to treat HER2+ breast cancer that’s advanced or metastatic include:

  • lapatinib (Tykerb)
  • tamoxifen (Soltamox)
  • fulvestrant (Faslodex)
  • paclitaxel
  • docetaxel (Taxotere)
  • trastuzumab (Herceptin)
  • pertuzumab (Perjeta)
  • ado-trastuzumab emtansine (Kadcyla)

You may wonder how Nerlynx compares with other medications that are prescribed for similar uses. Here we look at how Nerlynx and Femara are alike and different.

Ingredients

Nerlynx contains the active drug neratinib, which belongs to a class of medications called kinase inhibitors.

Femara contains the active drug letrozole, which belongs to a class of medications called aromatase inhibitors.

Uses

Nerlynx is FDA-approved for the treatment or management of certain types of breast cancer:

  • Early stage HER2-positive (HER2+) breast cancer. Nerlynx helps prevent the return of this type of cancer in adults who’ve previously taken trastuzumab (Herceptin). For this purpose, Nerlynx is used as an adjuvant therapy. This is a treatment used to prevent cancer from returning. (With HER2+ cancer, cancer cells have abnormally high levels of a protein called HER2.)
  • Advanced or metastatic HER2+ breast cancer. Nerlynx is used to treat this type of cancer in adults who’ve already tried two or more other HER2 breast cancer treatments. For this use, Nerlynx is taken with capecitabine (Xeloda). (Metastatic cancer is cancer that has spread to other areas of the body.)

Femara is FDA-approved for the following uses in women who’ve gone through menopause:

  • Advanced breast cancer. Femara can treat advanced breast cancer that’s hormone receptor-positive (HR+) or has an unknown hormone receptor status. For this purpose, Femara is used as a first-line or second-line treatment.
  • Hormone receptor-positive (HR+) early stage breast cancer. For this purpose, Femara is used as an adjuvant therapy.
  • Early stage breast cancer. Femara can be used as adjuvant therapy in women with early stage breast cancer who’ve already taken tamoxifen (Soltamox) for 5 years.

Drug forms and administration

Nerlynx comes as tablets that you take by mouth with food.

Femara comes as tablets that you take by mouth. You can take it with or without food.

Side effects and risks

Nerlynx and Femara have some similar side effects and others that differ. Below are examples of these side effects.

Mild side effects

These lists contain examples of mild side effects that can occur with Nerlynx, with Femara, or with both drugs (when taken individually).

  • Can occur with Nerlynx:
    • vomiting
    • abdominal (belly) pain
    • rash
    • swollen mouth or mouth sores
    • reduced appetite
    • nail problems, including color changes
    • back pain
  • Can occur with Femara:
    • hot flashes
    • joint or bone pain
    • excessive sweating, including night sweats
    • weight gain
    • headache
    • insomnia (trouble sleeping)
  • Can occur with both Nerlynx and Femara:
    • diarrhea
    • nausea
    • dizziness
    • constipation

Serious side effects

These lists contain examples of serious side effects that can occur with Nerlynx, with Femara, or with both drugs (when taken individually).

Effectiveness

Nerlynx and Femara have different FDA-approved uses, but they’re both used as adjuvant therapy for breast cancer.

These drugs haven’t been directly compared in clinical studies. However, studies have found both Nerlynx and Femara to be effective for helping prevent breast cancer from returning.

Costs

Nerlynx is a brand-name drug with no generic forms available. Femara contains the active drug letrozole, which is available as a generic drug. Brand-name medications usually cost more than generics.

According to estimates on WellRx.com, Nerlynx is significantly more expensive than Femara or letrozole. The actual price you’ll pay for any of these drugs depends on your insurance plan, your location, and the pharmacy you use.

Like Femara (above), Herceptin has uses similar to those of Nerlynx. Here’s a comparison of how Nerlynx and Herceptin are alike and different.

Ingredients

Nerlynx contains the active drug neratinib, which belongs to a class of medications called kinase inhibitors.

Herceptin contains the active drug trastuzumab, which is a monoclonal antibody that targets breast cancer cells.

Uses

Nerlynx is FDA-approved for the treatment or management of certain types of breast cancer:

  • Early stage HER2-positive (HER2+) breast cancer. Nerlynx helps prevent the return of this type of cancer in adults who’ve previously taken trastuzumab (Herceptin). For this purpose, Nerlynx is used as an adjuvant therapy. This is a treatment used to prevent cancer from returning. (With HER2+ cancer, cancer cells have abnormally high levels of a protein called HER2.)
  • Advanced or metastatic HER2+ breast cancer. Nerlynx is used to treat this type of cancer in adults who’ve already tried two or more other HER2 breast cancer treatments. For this use, Nerlynx is taken with capecitabine (Xeloda). (Metastatic cancer is cancer that has spread to other areas of the body.)

Herceptin is FDA-approved to treat:

  • HER2+ breast cancer. For this purpose, Herceptin is used as an adjuvant treatment. It may be used on its own or with other medications, depending on your treatment plan.
  • HER2+ breast cancer that’s metastatic. For this use, Herceptin may be used with paclitaxel, or it may be used on its own if you’ve received previous chemotherapy.
  • Metastatic gastric (stomach) cancer or gastroesophageal junction adenocarcinoma. Herceptin can treat these types of cancer when they’re HER2+ if you haven’t received treatment for metastatic stomach cancer before. For this use, Herceptin is used with cisplatin and either capecitabine or 5-fluorouracil.

Drug forms and administration

Nerlynx comes as tablets that you take by mouth with food.

Herceptin comes as a powder that’s mixed into a liquid solution. It’s given as an infusion (an injection into your vein that’s slowly dripped in over time). It should only be given by a healthcare professional.

Side effects and risks

Nerlynx and Herceptin have some similar side effects and others that differ. Below are examples of these side effects.

Mild side effects

These lists contain examples of mild side effects that can occur with Nerlynx, with Herceptin, or with both drugs (when taken individually).

  • Can occur with Nerlynx:
    • abdominal (belly) pain
    • swollen mouth or mouth sores
    • reduced appetite
    • nail problems, including color changes
    • weight loss
    • constipation
    • back pain
  • Can occur with Herceptin:
    • fever
    • infusion reactions
    • infections
    • cough
    • headache
    • shortness of breath
    • muscle pain
  • Can occur with both Nerlynx and Herceptin:
    • rash
    • nausea and vomiting
    • diarrhea
    • dizziness

Serious side effects

These lists contain examples of serious side effects that can occur with Nerlynx, with Herceptin, or with both drugs (when taken individually).

  • Can occur with Nerlynx:
    • severe diarrhea
    • liver problems
  • Can occur with Herceptin:
    • heart problems,* such as congestive heart failure
    • reaction to the infusion*
    • lung problems*
    • low white blood cell count, which can lead to increased infections
    • low red blood cell count, which can lead to anemia
    • blood clots
    • kidney problems
    • nerve damage
    • low level of platelets (a type of blood cell)
    • tumor lysis syndrome (when cancer cells release harmful chemicals into your blood)
  • Can occur with both Nerlynx and Herceptin:

* Herceptin has a boxed warning for this side effect. This is the most serious warning from the Food and Drug Administration (FDA).

Effectiveness

Nerlynx and Herceptin have different FDA-approved uses, but they’re both used as adjuvant therapy for breast cancer. They’re also both used for the treatment of metastatic breast cancer (cancer that has spread in the body).

These drugs haven’t been directly compared in clinical studies. However, studies have found both Nerlynx and Herceptin to be effective for helping prevent the recurrence of breast cancer, and for the treatment of metastatic breast cancer.

Costs

Nerlynx and Herceptin are both brand-name drugs. There are currently no generic forms of either drug. Brand-name medications usually cost more than generics.

According to estimates on WellRx.com, Nerlynx is significantly more expensive than Herceptin. The actual price you’ll pay for either drug depends on your insurance plan, your location, and the pharmacy you use.

You should take Nerlynx according to your doctor’s or healthcare provider’s instructions.

When to take

Nerlynx should be taken once a day. You can take it at any time of the day, but it’s recommended that you take it at the same time each day.

To help make sure you don’t miss a dose, try setting a reminder on your phone. A medication timer may be useful, too.

Taking Nerlynx with food

You should take Nerlynx with food.

Can Nerlynx be crushed, split, or chewed?

No, Nerlynx can’t be crushed, split, or chewed. You should swallow the Nerlynx tablet whole.

It’s not known if Nerlynx is safe to take during pregnancy. However, animal studies suggest that Nerlynx can cause harm to a developing fetus.

In studies of rabbits who received Nerlynx while pregnant, fetal death and abnormalities, as well as side effects in the mother, were seen. Examples of effects seen in rabbits included problems with the fetus’s growth, such as in the bones, soft tissue, and brain.

If you’re pregnant or planning a pregnancy, talk with your doctor before starting Nerlynx.

It’s not known if Nerlynx is safe to take during pregnancy. The drug’s manufacturer recommends that females who can become pregnant should use birth control while taking Nerlynx and for at least 1 month after their last dose. Men with female partners who can become pregnant should use effective contraception while taking Nerlynx, and for 3 months after their last dose.

If you’re sexually active and you or your partner can become pregnant, talk with your doctor about your birth control needs while you’re using Nerlynx.

It’s not known if Nerlynx is safe to use while breastfeeding or if the drug passes into breast milk. The drug’s manufacturer recommends that you shouldn’t breastfeed while taking Nerlynx, and for at least 1 month after your last dose.

If you have questions about breastfeeding while taking Nerlynx, talk with your doctor.

Here are answers to some frequently asked questions about Nerlynx.

Is Nerlynx a chemotherapy drug?

No, Nerlynx isn’t a chemotherapy drug. It works differently than chemotherapy drugs.

Chemotherapy drugs work by killing rapidly growing cells in your body. Cancer cells are usually fast-growing cells, so they’re affected by chemotherapy. However, some healthy cells in your body are also fast-growing cells. Chemotherapy drugs can also affect these healthy cells. This can raise your risk for side effects.

Nerlynx contains the active drug neratinib, which belongs to a class of medications called kinase inhibitors. Nerlynx works to kill cancer cells by permanently attaching to cancer cell receptors (docking stations). By attaching to these receptors, Nerlynx can prevent cancer cells from growing. This causes cancer cells to die.

How can I help prevent diarrhea during my Nerlynx treatment?

To lower your risk for severe diarrhea while taking Nerlynx, your doctor may prescribe an antidiarrheal drug called loperamide (Imodium).

Diarrhea is a common side effect of Nerlynx. In some cases, this can lead to severe side effects like kidney problems or dehydration (low fluid levels in the body).

In one clinical study, 95% of people who took Nerlynx experienced diarrhea. In comparison, 35% of people who took a placebo (a treatment with no active drug) had diarrhea. Most of the people who had diarrhea experienced it within the first month of their treatment, and it lasted about 8 days.

Talk with your doctor if you’re concerned about diarrhea during your Nerlynx treatment.

While using Nerlynx, which over-the-counter drugs can I take to reduce stomach acid or indigestion?

Certain drugs can be used to reduce indigestion or stomach acid while taking Nerlynx. However, you need to take them a certain amount of time before or after your Nerlynx dose.

Examples of drugs that should be taken at least 2 hours after your dose of Nerlynx, or 10 hours before your dose of Nerlynx, include:

  • famotidine (Pepcid, Pepcid AC)
  • cimetidine (Tagamet)
  • nizatidine (Axid)

Examples of drugs that should be taken at least 3 hours before Nerlynx include:

  • calcium carbonate (Tums)
  • bismuth subsalicylate (Pepto-Bismol)
  • aluminum hydroxide (found in products such as Gaviscon and Mylanta)
  • aluminum-magnesium hydroxide (Maalox)
  • calcium carbonate/magnesium hydroxide (Rolaids)
  • magnesium hydroxide (Milk of Magnesia)
  • citric acid/aspirin/sodium bicarbonate (Alka-Seltzer)

Certain drugs that reduce stomach acid or indigestion shouldn’t be taken with Nerlynx. If taken together, these drugs may reduce your body’s ability to absorb Nerlynx. This can result in Nerlynx not working as well as it should to kill cancer cells.

Examples of drugs to completely avoid while taking Nerlynx include:

Can Nerlynx cure breast cancer?

No, Nerlynx isn’t used to cure breast cancer. It’s approved to treat breast cancer in the following ways:

  • To prevent the return of early stage HER2-positive (HER2+) breast cancer in adults who’ve previously taken trastuzumab (Herceptin). (With HER2+ cancer, the cancer cells have abnormally high levels of a protein called HER2.) For this purpose, Nerlynx is used as an adjuvant therapy (treatment used to prevent cancer from returning).
  • To treat HER2+ breast cancer that’s advanced or metastatic (has spread to other areas of the body) in adults who’ve already tried two or more other HER2 breast cancer treatments. For this purpose, Nerlynx is taken with capecitabine (Xeloda).

Talk with your doctor if you have questions about how Nerlynx works to treat your breast cancer.

Before taking Nerlynx, talk with your doctor about your health history. Nerlynx may not be right for you if you have certain medical conditions or other factors affecting your health. These include:

  • Liver damage. One of the possible side effects of Nerlynx is liver damage. If you already have liver damage, your doctor may monitor you more closely during your Nerlynx treatment.
  • Pregnancy. It’s unknown if Nerlynx is safe to take during pregnancy. For more information, see the “Nerlynx and pregnancy” section above.
  • Breastfeeding. It’s not known if it’s safe to breastfeed while taking Nerlynx, but the drug’s manufacturer doesn’t recommend doing so. For more information, see the “Nerlynx and breastfeeding” section above.

Note: For more information about the potential negative effects of Nerlynx, see the “Nerlynx side effects” section above.

Using more than the recommended dosage of Nerlynx can lead to serious side effects.

Do not use more Nerlynx than your doctor recommends.

Overdose symptoms

Symptoms of an overdose can include:

  • diarrhea
  • nausea
  • vomiting
  • dehydration (low fluid levels in the body)

What to do in case of overdose

If you think you’ve taken too much of this drug, call your doctor. You can also call the American Association of Poison Control Centers at 800-222-1222 or use their online tool. But if your symptoms are severe, call 911 or go to the nearest emergency room right away.

When you get Nerlynx from the pharmacy, the pharmacist will add an expiration date to the label on the bottle. This date is typically 1 year from the date they dispensed the medication.

The expiration date helps guarantee that the medication is effective during this time. The current stance of the Food and Drug Administration (FDA) is to avoid using expired medications. If you have unused medication that has gone past the expiration date, talk to your pharmacist about whether you might still be able to use it.

Storage

How long a medication remains good can depend on many factors, including how and where you store the medication.

Nerlynx tablets should be stored at room temperature between 68°F and 77°F (20°C and 25°C) in a tightly sealed container away from light. Avoid storing this medication in areas where it could get damp or wet, such as bathrooms.

Disposal

If you no longer need to take Nerlynx and have leftover medication, it’s important to dispose of it safely. This helps prevent others, including children and pets, from taking the drug by accident. It also helps keep the drug from harming the environment.

The FDA website provides several useful tips on medication disposal. You can also ask your pharmacist for information on how to dispose of your medication.

The following information is provided for clinicians and other healthcare professionals.

Indications

Nerlynx is indicated for the prevention of recurrence of early stage human epidermal growth factor receptor-positive (HER2+) breast cancer in adults who have already received adjuvant Herceptin (trastuzumab)-based therapy.

Nerlynx is also indicated to treat advanced or metastatic HER2+ breast cancer in adults. For this purpose, Nerlynx is taken in combination with capecitabine (Xeloda) as part of a chemotherapy regimen. It should be reserved for people who have already undergone HER2+ breast cancer treatment with at least two other anti-HER2-based regimens.

Mechanism of action

Nerlynx contains the active drug neratinib, which is an intracellular kinase inhibitor. It irreversibly binds to the epidermal growth factor receptor (EGFR) and the human epidermal growth factor receptor (HER2 and HER4), which results in a reduction in EGFR and HER2 autophosphorylation as well as a reduction in downstream signaling pathways.

Pharmacokinetics and metabolism

Nerlynx reaches peak plasma concentrations within 2 to 8 hours of oral administration. Following a single oral dose, the mean elimination half-life of Nerlynx is 7 to 17 hours.

Nerlynx is metabolized by the liver, primarily via the CYP3A4 metabolic pathway, with some metabolism through flavin-containing monooxygenase (FMO). It is excreted through the fecal route (97.1%) and urine (1.13%) within 96 hours of initial oral administration.

Contraindications

There are no contraindications to Nerlynx.

Storage

Nerlynx tablets should be stored at room temperature between 68°F and 77°F (20°C and 25°C). Excursions between 59°F and 86°F (15°C and 30°C) are permitted.

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or other healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.