According to Genentech, the manufacturer of Herceptin, approximately 35,000 women have been given Herceptin since it first received FDA approval. However, not all breast cancer patients are candidates for Herceptin. The drug only appears to work for women whose breast cancer cells carry extra copies of a protein called HER2 (also written HER2/neu).

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What is HER2?

HER2 (human epidermal growth factor receptor 2) is a protein found on the surface of cells that, when functioning normally, has been found to be a key component in regulating cell growth. However, when the HER2 protein is altered, extra HER2 protein receptors may be produced. This over-expression of HER2 causes increased cell growth and reproduction, often resulting in more aggressive breast cancer cells.

[Karl Note: What is the nature of the "alteration" of the HER2 protein? 

FROM HERE we find that there is a mutation of a gene that causes the HER2 to become "altered," and then to multiply more rapidly than is is designed to multiply.  We are back to the action of free radicals.  This aspect of this drug is well hidden.  Free radicals are the cause of all cancers, but since drugs cannot neutralize or remove free radicals, drugs are designed to handle the next logical step in the progress of the problem.

In other words, a free radical causes the gene to change.  When it is the gene of the normal HER2 cell, that cell has been altered.

This abnormal HER2 reproduces more rapidly than it should.

That reproduction has various actions related to it, and they have found a drug that prevents one of those actions.

Wouldn't it be far better to find something (obviously not a drug) that would prevent the gene mutation in the first place.

So, here is the heart and soul of the fraud of drug-driven cancer research.

The researchers KNOW what causes cancer.  They also KNOW that there is no money in explaining that cause.  So, they look for some symptom of that cause, or a symptom of a symptom of a symptom where, finally, a drug can cause an effect -- usually an "inhibiting" effect.

In other words a cell or substance in the body is normal, becomes abnormal because of the free radical damage.  That's too early on the chain.  That abnormal material then is the cause of some symptom, called a new cause. This new cause is, itself, responsible for another symptom.

That next symptom COULD be called another cause.  It is only a label, after all.

Finally they get down the line of this sequence to a point, far from the original cause (the free radical) where a drug can cause an effect.

They create the drug, get a patent, and the company becomes the darling of Wall Street.

This is big business at work.

Karl Loren]

HER2 protein over-expression affects approximately 25% to 30% of breast cancer patients. Women with HER2 over-expression may not be as responsive to standard breast cancer treatments, including certain regimens of chemotherapy.

How Do Physicians Test for HER2?

HER2 testing is becoming more common. Knowing the results of the test can help physicians and patients determine which treatment options are most likely to be effective. HER2 testing is performed on cancer cells that have been removed during breast biopsy or breast cancer surgery. Testing may also be performed on cells from a breast tissue sample that has been stored from a previous biopsy (many laboratories keep tissue samples for years after the initial biopsy or surgery).

Testing for HER2 protein over-expression involves staining the tissue sample with a specific solution in a pathology laboratory. The pathologist then examines the cells within the tissue sample, checking for highlighted areas where high levels of HER2 over-expression are present. Depending on the level of staining, the patient’s cancer may be classified as HER2 positive or HER2 negative.

How Does Herceptin Work?

The drug Herceptin is a monoclonal antibody engineered through biotechnology. It targets breast cancer cells that have too many copies of the HER2 protein. After it has identified which cells over-express the HER2 protein, Herceptin attaches itself to the HER2 protein receptors on the surface of these cells. By binding to the cells, Herceptin slows the growth and spread of tumors that have an overabundance of HER2. Many experts believe that Herceptin represents the future direction of breast cancer drugs in that it targets a particular protein of the cancer cell and prevents it from carrying out its action, similar to the new leukemia drug, Gleevec. Herceptin is given intravenously (through the vein) in an outpatient clinical setting.

Who is a Candidate for Herceptin?

Currently, Herceptin is only FDA approved for women with advanced (metastatic) breast cancer whose cancers over-express the HER2 protein. However, several large clinical trials are enrolling/testing patients to determine whether Herceptin is helpful for early-stage breast cancer. The trials plan to enroll more than 10,000 patients at 800 sites worldwide. Women who are interested in learning more about clinical trials with Herceptin should talk to their physicians, contact a large hospital or academic medical center in their area, or check online clinical trial listings for more information.

What Have Clinical Tests of Herceptin Shown Prior to FDA Approval?

Herceptin was shown to slow the growth and spread of cancerous tumors in a number of clinical trials prior to FDA approval in 1998. In some cases, cancerous tumors completely disappeared in patients taking Herceptin.

In one clinical trial, 469 patients with metastatic cancer who over-expressed HER2 received either Herceptin with chemotherapy or Herceptin alone. Among the 235 women who received Herceptin with chemotherapy, researchers saw significantly less rapid tumor growth. Many tumors were reduced by 50% or more in size, and the one-year cancer survival rate was higher compared to women who underwent chemotherapy alone (79% versus 68%).

Herceptin was also shown to be effective on its own in clinical trials prior to FDA approval. For example, among the 222 women who took Herceptin alone, 14% experienced a reduction in tumor size, and tumors completely disappeared in 3% of patients. These tumor responses lasted six weeks to 18 months after Herceptin treatment had ended.

What Have Clinical Tests of Herceptin Shown After FDA Approval?

Studies conducted after Herceptin received FDA approval continue to show its effectiveness in treating advanced breast cancer patients who carry extra copies of the HER2 gene. However, studies have also shown that Herceptin increases the risk of serious heart problems.

In a study published in the March 2001 issue of The New England Journal of Medicine, lead researcher Dennis Slamon, MD, PhD and his colleagues gave 469 advanced breast cancer patients either standard chemotherapy or chemotherapy with Herceptin. All of the patients had tested positive for HER2 protein over-expression. Depending on the patients’ previous treatment, the chemotherapy regimens given in the trial were:

After one year, the researchers observed fewer deaths among the women who took Herceptin: only 22% of the women who took Herceptin died after one year compared with 33% of the women who did not take Herceptin.

"The study by Slamon et al. is a landmark trial…. This is the beginning of an important new era in cancer treatment since many more targeted therapies are now undergoing clinical evaluation," wrote Elizabeth A. Eisenhauer, MD, in an accompanying editorial in The New England Journal of Medicine. The average survival time was also greater among the women who took Herceptin: 25 months compared to 20 months among the women who did not take Herceptin. Click here to learn more about this study and Dr. Eisenhauer’s accompanying editorial.

Similarly, at the San Antonio Breast Cancer Symposium in December 2000, researchers from the Sarah Cannon Cancer Center in Nashville, Tennessee found that among 46 patients who over-expressed the HER2 protein, 25% of the tumors responded to Herceptin. Among those patients who added a weekly regimen of the drug Taxol (generic name, paclitaxel) and Paraplatin (generic name, carboplatin) to Herceptin, 56% showed some response. Weekly Taxol and Paraplatin without Herceptin was also effective in some advanced breast cancer patients who did not respond well to Herceptin. Click here to learn more about this study.

While the results of studies such as these reveal that Herceptin can be beneficial for women with advanced breast cancer, Herceptin has also been found to cause serious heart problems (cardiotoxicity). Therefore, all patients who take Herceptin should have their hearts monitored before and during treatment (see Side Effects section below for more information).

In rare cases, women who have been given Herceptin have experienced allergic shock or respiratory distress. These reactions were not observed in clinical trials prior to FDA approval. However, warning labels accompanying Herceptin packaging have since been amended to include these possible effects.

What are the Side Effects of Herceptin?

As with all drugs, Herceptin has been shown to cause a variety of side effects, some of which are potentially severe. The common side effects (such as fever, chills, weakness, or nausea) listed in this section occurred in more than 25% of women who were given Herceptin with or without other drugs in clinical studies. These symptoms were treatable and were not as frequent after the initial treatment with Herceptin. The less common side effects listed in this section occurred in less than 10% of women who were given Herceptin with or without other drugs in clinical studies.

Common side effects of Herceptin include:

Less common side effects of Herceptin include:

Heart problems with Herceptin: In a small number of women, Herceptin alone or in combination with chemotherapy can lead to serious heart problems including ventricular dysfunction and congestive heart failure. This life-threatening side effect is more common among patients who receive Herceptin in combination with the AC chemotherapy regimen (chemotherapy consisting of an anthracycline, such as Adriamycin or Ellence, and cyclophosphamide). However, Herceptin is not approved for use with this chemotherapy drug combination outside of the clinical trial setting. Women considering Herceptin should have their heart function evaluated by a physician before beginning treatment. Once on Herceptin, women should be closely monitored for any heart problems that may occur.

Recent News Articles About Herceptin and/or HER2

Additional Resources and References

Update: July 24, 2001

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