Enhertu for Breast Cancer: Benefits, Side Effects, and Cost

Enhertu (fam-trastuzumab deruxtecan-nxki, trastuzumab deruxtecan, or T-DXd for short), pronounced en-HER-too, is a medication used to treat breast cancer. This medication was approved by the Food and Drug Administration (FDA) on May 4, 2022, to treat breast cancer when specific circumstances or guidelines are met. It can also treat other types of cancer, including stomach and lung cancers.

This article discusses how Enhertu works, its dosages, side effects, cost, and affordability.

How Does Enhertu Treat Breast Cancer?

Enhertu can treat metastatic (cancer that has spread from its initial location to distant body parts) HER2-positive breast cancer or recurring breast cancer that cannot be removed surgically. HER2-positive breast cancer is diagnosed when a tumor grows faster due to higher levels of a protein called human epidermal growth factor receptor 2, or HER2.

Enhertu is administered intravenously (IV) (into the vein) through a method called infusion therapy. It is an antibody drug conjugate (ADC), a type of targeted drug, meaning it travels to the tumor and releases chemotherapy to the cells that produce too much HER2, directly killing the cells that harm the body.

Dosing and When to Take Enhertu

Healthcare professionals may recommend Enhertu to people who are at least 18 years old and have the following characteristics:

• Breast cancer that cannot be treated with surgery (unresectable), is HER2-positive and has already been treated with anti-HER2 therapy, or is recurring
• Breast cancer that is HER2-positive, has metastasized, and has already been treated with anti-HER2 therapy
• Breast cancer that cannot be treated with surgery, is HER2-low (low levels of HER2 but not enough to be considered HER2-positive), and has already been treated with anti-HER2 therapy
• Breast cancer that is HER2-low, has metastasized, and has already been treated with anti-HER2 therapy
• Non-small cell lung cancer (NSCLC) that cannot be treated with surgery, has a specific HER2 gene mutation, and has already been treated
• NSCLC that has a specific HER2 gene mutation, has metastasized, and has already been treated
• HER2-positive gastric or gastroesophageal junction adenocarcinoma stomach cancer that has spread and has already been treated

Enhertu is administered intravenously. A 5.4 milligrams to kilograms (mg/kg) dose is typically administered once every 21 days. The length of time people receive treatment varies, with seven months being the midrange treatment.

Side Effects

The most common side effects of Enhertu are:

• Diarrhea
• Fatigue
• Hair loss or thinning
• Nausea
• Sleepiness
• Vomiting

More severe side effects, such as breathing difficulties or heart problems, are also possible. Talking to a healthcare provider about new symptoms and side effects is important to ensure they are not serious. Some side effects may be life-threatening, so it is essential to receive care immediately.

Cost and Affordability

Cancer treatments cost Americans roughly $5.6 billion per year in out-of-pocket costs. Many people with cancer pay over $100,000 out-of-pocket costs within the first year of diagnosis. In addition to insurance, there are other patient-assistance options.

People receiving Enhertu treatments may benefit from options such as:

• The Enhertu patient savings program
• Patient-assistance programs
• Independent foundations

These options may help with the drug cost and other expenses related to treatment, including drug administration and transportation expenses.

Summary

Enhertu (trastuzumab deruxtecan) is a drug used to treat breast and other cancers with high levels of the HER2 protein, which makes tumors grow quickly. Enhertu is administered intravenously (in the vein), targeting and killing the specific cells that produce too much HER2.

Treatments are usually administered once every three weeks; treatment time varies, but the midrange treatment schedule is typically around seven months.Common side effects include nausea, fatigue, and hair loss. More severe side effects include heart and lung problems. Talking with a healthcare professional about any new or worsening symptoms is essential.

A Word From Verywell

Deciding on and beginning a new medication or therapy for cancer treatment can be challenging. Talk to your oncologist or healthcare team if you think Enhertu may be a promising treatment for you. Evidence supports that it is an effective treatment for HER2-positive breast cancer and other cancers.