Herceptin

Herceptin is a prescription medication used to treat breast cancer. However, not all women with breast cancer will benefit from it, because the medication is targeted to treat cancers that have a high concentration of HER2 receptors (a protein on the outside of certain cancer cells). You can receive your Herceptin dose intravenously every seven days at your healthcare provider's office, a hospital, or an infusion center. Potential side effects include diarrhea, nausea, and fatigue.

 

What Is Herceptin?

Herceptin® (trastuzumab) is a prescription medication used to treat breast cancer.
 
(Click Herceptin Uses for more information on what the drug is used for, including possible off-label uses.)
 

Who Makes Herceptin?

It is made by Genentech, Inc.
 

How Does It Work?

Herceptin is part of a group of medications called monoclonal antibodies. Monoclonal antibodies are used to treat a wide variety of conditions, including breast cancer. Herceptin is a special type of monoclonal antibody that is designed to bind to HER2, a protein on the outside of certain cancer cells. When Herceptin binds to HER2 receptor proteins, it has several effects. It may interfere with the cancer cells' ability to grow and multiply. By binding to the HER2 receptor, the drug may also serve as a signal to the immune system, which can help destroy the cancer cells.
 
Herceptin is not a form of chemotherapy. It is a biologic therapy, also known as biological therapy (see Biological Therapy for Breast Cancer). It is less "toxic" than chemotherapy, as it specifically targets the HER2 receptors. Because it is only used to treat cancers that have a high concentration of HER2 receptors, it targets the tumors, having less of an effect on healthy, noncancerous cells.
 
Before the medication can be prescribed for a particular patient, certain tests must be performed to make sure that the tumor "overexpresses" HER2. When a cell makes a certain receptor or protein, it is said to "express" that receptor or protein. Tumor cells that overexpress HER2 have a high concentration of the HER2 receptor. Not all breast cancers overexpress HER2, and not all people with breast cancer will benefit from Herceptin.
 

Effects of Herceptin

Several studies have looked at the effects of this drug for breast cancer treatment.
 
One study looked at Herceptin for the adjuvant treatment of breast cancer. Adjuvant therapy for breast cancer is treatment that follows breast cancer surgery (with or without radiation). It is given to help prevent the cancer from returning. These studies compared chemotherapy alone to chemotherapy plus Herceptin for breast cancers that were HER2-positive. The chemotherapy regimen included doxorubicin (Adriamycin®, Rubex®), cyclophosphamide (Cytoxan®), and paclitaxel (Onxol®, Taxol®). After 3.5 years, 93 percent of people who had taken chemotherapy plus Herceptin had survived cancer-free, compared to 86 percent of those who took chemotherapy alone.
 
Another study looked at using it in combination with chemotherapy for metastatic breast cancers (breast cancer that has spread to other parts of the body) that were HER2-positive. When Herceptin and chemotherapy were combined in these cases, the tumors shrunk more than when chemotherapy was used alone. Also, those taking it with chemotherapy lived longer and had a delay in the worsening of their cancer, compared to those who took chemotherapy alone.
 

When and How to Take Herceptin

Some general considerations for when and how to take the medication include the following:
 
  • It is given intravenously (by IV) every seven days.
     
  • Your first Herceptin infusion will last 90 minutes, and subsequent infusions will last 30 minutes.
     
  • Most people receive their infusion at their healthcare provider's office, a hospital, or at an "infusion center."
     
  • For the medication to work properly, it must be taken as prescribed. Herceptin will not work as well if you stop taking it before your healthcare provider recommends.
     

Dosing Information

The dosage that your healthcare provider recommends will vary, depending on a number of factors, including:
 
As is always the case, do not adjust your dose unless your healthcare provider specifically instructs you to do so.
 
(Click Herceptin Dosage for more information.)
 

Side Effects

As with any medicine, side effects are possible with Herceptin. However, not everyone who takes the drug will experience side effects. In fact, most people tolerate it quite well. If side effects do occur, in most cases, they are minor and either require no treatment or can easily be treated by you or your healthcare provider. Serious side effects are less common.
 
Common side effects of Herceptin include, but are not limited to:
 
  • Pain
  • Fatigue or weakness
  • Fever
  • Nausea
  • Diarrhea.
     
(Click Herceptin Side Effects to learn more, including potentially serious side effects that you should report immediately to your healthcare provider.)
 
The following eMedTV articles describe specific side effects of the drug:
 

Drug Interactions With Herceptin

Herceptin can potentially interact with a few other medicines (see Herceptin Drug Interactions).
 

What Should I Tell My Healthcare Provider?

You should talk with your healthcare provider prior to taking it if you have:
 
Also, let your healthcare provider know if you are:
 
Make sure to tell your healthcare provider about all of the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements.
 
(Click Herceptin Warnings and Precautions to learn more, including information on who should not take the drug.)
 

What If I Take an Overdose?

In studies, large doses of Herceptin did not cause any serious problems. It is unlikely for a person to overdose on this drug, as it is administered by a healthcare provider.
 

What Should I Do If I Miss a Dose?

If you do not take your Herceptin as scheduled, talk to your healthcare provider as soon as possible to set up your next infusion appointment.
 

Strengths

Herceptin is available in vials containing 440 mg of dry powdered Herceptin. It must be mixed and diluted prior to use.
 

Is There a Generic Version of Herceptin?

Currently, there is no generic Herceptin licensed for sale (see Generic Herceptin).
Written by/reviewed by: Kristi Monson, PharmD; Arthur Schoenstadt, MD
Last reviewed by: Kristi Monson, PharmD;