Nerlynx (chemical name: neratinib) was approved by the U.S. Food and Drug Administration (FDA) on July 17, 2017 to treat early-stage, HER2-positive breast cancer for an extended period after surgery (doctors call this extended adjuvant therapy) in people who have previously been treated with Herceptin (chemical name: trastuzumab).
Nerlynx is the first medicine to be approved specifically for extended adjuvant therapy for early-stage, HER2-positive disease.
Nerlynx fights HER2-positive breast cancer by blocking the cancer cells’ ability to receive growth signals. Nerlynx is a pill taken by mouth.
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.
Herceptin works by attaching to the HER2 protein and blocking it from receiving growth signals. Herceptin, which is given intravenously, is approved by the U.S. Food and Drug Administration (FDA) to:
- treat advanced-stage, HER2-positive breast cancers
- be given to women with earlier stages of HER2-positive disease as adjuvant treatment (treatment after initial treatment, such as surgery) either alone or as part of a regimen with chemotherapy
A newer form of Herceptin, Herceptin Hylecta (chemical name: trastuzumab and hyaluronidase-oysk), can be given as an injection.
The recommended dose of Nerlynx is 240 mg (6 tablets) once per day with food for 1 year.
The FDA approval is based on results from the ExteNET study. The study found that Nerlynx improved disease-free survival in women diagnosed with early-stage, HER2-positive breast cancer when given within 2 years after surgery and a chemotherapy regimen that included Herceptin. After 2 years of follow-up, disease-free survival rates were:
- 93.9% for women treated with Nerlynx
- 91.6% for women treated with placebo (a dummy pill that looked just like Nerlynx but contained no medicine)
This difference was statistically significant, which means it was likely because of the Nerlynx treatment and not just due to chance.
Disease-free survival is how long a woman lives without the cancer growing.
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 vomiting, nausea, abdominal pain, fatigue, rash, and mouth sores.
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
“Despite advances in the treatment of early stage, HER2-positive breast cancer, there remains a need for further therapeutic improvements in order to attempt to further reduce the risk of disease recurrence,” said Puma Biotechnology CEO and President Alan H. Auerbach. “We are pleased to be able to bring this new medicine to patients with breast cancer. We would like to express our appreciation to the patients, caregivers, and physicians who contributed to the neratinib clinical development program and, more specifically, the ExteNET trial.”
If you’ve been diagnosed with early-stage, HER2-positive breast cancer and have been treated with surgery and a chemotherapy regimen that included Herceptin, you may want to talk to your doctor about Nerlynx and ask if it makes sense for your unique situation.
Editor’s Note: This article was updated with information about Herceptin Hylecta, which the FDA approved on Feb. 28, 2019.