Nerlynx (chemical name: neratinib) is a targeted therapy used to treat early-stage, HER2-positive breast cancer for an extended period of time after surgery (doctors calls this extended adjuvant therapy). You take Nerlynx within 2 years after you’ve had surgery and completed a chemotherapy regimen that included Herceptin (chemical name: trastuzumab).
Nerlynx is a pill taken by mouth. The recommended dose of Nerlynx is 240 mg (6 tablets) once per day with food for 1 year.
Learn more about:
- How Nerlynx works
- Is Nerlynx right for you?
- What to expect when taking Nerlynx
- Paying for Nerlynx
- Nerlynx side effects
HER2-positive breast cancers make too much of the HER2 protein. The HER2 protein sits on the surface of cancer cells and receives signals that tell the cancer to grow and spread. About one out of every four breast cancers is HER2-positive. HER2-positive breast cancers tend to be more aggressive and harder to treat than HER2-negative breast cancers. Nerlynx is an irreversible pan-HER inhibitor. Nerlynx fights HER2-positive breast cancer by blocking the cancer cells’ ability to receive growth signals.
Nerlynx is a targeted therapy, but unlike Herceptin (chemical name: trastuzumab), Kadcyla (chemical name: T-DM1 or ado-trastuzumab emtansine), and Perjeta (chemical name: pertuzumab), it is not an immune targeted therapy. Immune targeted therapies are versions of naturally occurring antibodies that work like antibodies made by our immune systems. Nerlynx is a chemical compound, not an antibody.
Four different tests can be used to figure out if the cancer is HER2-positive and if it will likely respond to Nerlynx:
IHC is the most commonly used test to see if a tumor has too much of the HER2 receptor protein on the surface of the cancer cells.
The IHC test gives a score of 0 to 3+ that indicates the amount of HER2 receptor protein in tumors. If the tumor scores 0 to 1+, it's called "HER2 negative." If it scores 2+ or 3+, it's called "HER2 positive."
Women with IHC positive scores tend to respond favorably to Nerlynx. The drug is not considered effective for tumors with IHC scores of 0 or 1+.
It's important to note that results on the IHC test may vary from lab to lab, and that some labs are more proficient at HER2 testing than others. Discuss with your doctor whether you might want to get a FISH test, especially if you have a 1+ or 2+ result from IHC. That way you can get another measure of whether the tumor might respond well to Nerlynx.
The IHC test results are most reliable for fresh or frozen tissue samples. IHC tends to be an unreliable way to test tissue that's preserved in wax or other chemicals. FISH testing is the preferred way to assess preserved tissue samples.
FISH (Fluorescence In Situ Hybridization)
The FISH test looks for the HER2 gene abnormality. This test is the most accurate, but less available, way to find out if a breast tumor is likely to respond to Nerlynx. The FISH test shows how many copies of the HER2 gene are in tumor cells. The more copies of the gene, the more HER2 receptors the cells have.
With the FISH test, you get a score of either "positive" or "negative" (some hospitals call a negative test "zero"). If the cancer is FISH positive, it will probably respond well to Nerlynx.
SPoT-Light HER2 CISH (Subtraction Probe Technology Chromogenic In Situ Hybridization)
The SpoT-Light HER2 CISH test looks for how many copies of the HER2 gene are in the tumor cells of a breast cancer tissue sample. The SPoT-Light test is less complicated than the FISH or IHC tests. The SPoT-Light test can be used on fresh tissue samples or tissue samples that have been stored in wax or other chemicals, but it doesn't work on frozen tissue samples.
With the SPoT-Light test, you get a score of either "positive" or "negative." If the cancer is SPoT-Light positive, it will probably respond well to Nerlynx.
Inform HER2 Dual ISH (In Situ Hybridization)
The Inform HER2 Dual ISH test uses a special stain that makes HER2 proteins change color. The test can be used on tissue samples that have been stored in wax or other chemicals. The Inform HER2 Dual ISH test offers more precise results than the IHC HER2 test. It is also less expensive and doesn’t need the special microscope of the FISH HER2 test.
With the Inform HER2 Dual ISH test, you get a score of either “HER2 positive” or “HER2 negative.”
Learn more about Breast Cancer Tests.
If you take an antacid medicine, such as a proton pump inhibitor or an H2-receptor antagonist, you should wait 3 hours after taking the antacid to take Nerlynx. Prilosec, Prevacid, and Nexium are common proton pump inhibitors. Pepcid, Tagamet, and Zantac are common H2-receptor antagonists.
You should not take a type of medicine called a CYP3A inhibitor at the same time as Nerlynx because it increases the effects of Nerlynx. This class of medicines includes antifungal medicines such as Onmel (chemical name: itraconazole) and Biaxin (chemical name: clarithromycin), as well as antiretroviral drugs used to treat HIV such as Kaletra (chemical names: lopinavir and ritonavir).
You should not take a type of medicine called a CYP3A inducer at the same time as Nerlynx because it decreases the effects of Nerlynx. This class of medicines includes Rifamate (chemical name: rifampin), an antibiotic used to treat tuberculosis, and Carbatrol (chemical name: carbamazepine), which is used to control certain types of seizures in people with epilepsy.
You should not eat grapefruit or pomegranate or drink grapefruit juice or pomegranate juice, because they can increase the effects of Nerlynx.
Women who are pregnant or nursing or are planning to get pregnant should not take Nerlynx. Nerlynx can cause embryo death and birth defects. It’s important that you don’t get pregnant while you’re taking Nerlynx; you must use effective birth control.
If your doctor prescribes Nerlynx and you have problems paying for the medicine, the Nerlynx patient support program may be able to help you. Puma Biotechnology, the company that makes Nerlynx, has created a co-pay card for Nerlynx to help people pay for out-of-pocket costs associated with Nerlynx. To be eligible, you must have commercial insurance. For more information, visit the Nerlynx co-pay card webpage.
Severe diarrhea soon after starting Nerlynx is a very common side effect. In the ExteNET trial, about 40% of the women treated with Nerlynx had severe diarrhea as a side effect.
The FDA approval recommends that loperamide (brand names include Imodium, Kaopectate 1-D, and Pepto Diarrhea Control) be given with Nerlynx for the first 56 days of treatment and then as needed to help manage diarrhea.
Other common side effects of Nerlynx are:
In rare cases, Nerlynx may cause serious liver problems. Tell your doctor right away if you have any of the following signs of liver problems:
- yellowing of the skin or the whites of the eyes
- dark or brown urine
- feeling very tired
- loss of appetite
- pain on the upper right side of the abdomen
- bleeding or bruising more easily than normal
- Nerlynx (neratinib) prescribing information. Puma. Los Angeles, CA. 2018. Available at: https://nerlynx.com/pdf/full-prescribing-information.pdf.