HERCEPTIN (TRASTUZUMAB)

Herceptin is one of a new group of cancer drugs called monoclonal antibodies.Herceptin is indicated in combination with paclitaxel for treatment of HER2-overexpressing metastatic breast cancer, as well as, a single agent for treatment of HER2-overexpressing breast cancer in patients who have received one or more chemotherapy regimens for metastatic disease
Herceptin is the only HER2-targeted therapy with approved indications in both the adjuvant and metastatic settings.
Herceptin is indicated as part of a treatment regimen containing doxorubicin, cyclophosphamide, and paclitaxel for the adjuvant treatment of HER2-overexpressing breast cancer, as well as, a single agent, for the adjuvant treatment of HER2-overexpressing node-negative (ER/PR-negative or with one high-risk feature) or node-positive breast cancer, following multi-modality anthracycline-based therapy.
Herceptin (chemical name: trastuzumab) is a very effective treatment against HER2-positive breast cancer in women with stage II, III, and IV disease (medium to large cancers or cancers with lymph nodes involved or metastatic disease). It is given intravenousy into the bloodstream once every one to three weeks.

ACTION HERCEPTIN ( TRASTUZUMAB )
Herceptin stops or slows the growth of certain breast cancer cells by blocking the chemical signals they need to grow.
Chromosomes inside every cell contain genes, which regulate the cell's growth, rest, and repair. The genes do this by ordering the production of special proteins that tell the cells what to do. Each protein sets off a step in a chain of reactions, resulting in the desired cell activity growth, rest, or repair. Herceptin is a special antibody protein medication that attaches itself to the HER2 receptors on the cancer cells and blocks them from receiving growth signals. Herceptin can also alert the immune system to destroy the cancer cells it attaches to.
Herceptin works by interfering with one of the ways in which breast cancer cells divide and grow. Some breast cancer cells divide and grow when a protein that naturally occurs in the body (known as human epidermal growth factor) attaches itself to another protein known as HER2, which is found on the surface of some breast cancer cells. Herceptin blocks this process by attaching itself to the HER2 protein so that the epidermal growth factor cannot reach the breast cancer cells. This stops the cells from dividing and growing. Herceptin also works by attracting the body’s own immune cells to help destroy the cancer cells.


HOW IS HERCEPTIN ( TRASTUZUMAB ) GIVEN :
Herceptin is given by a drip (infusion) through a fine tube (cannula) inserted into a vein. which means it is dripped into your body through a needle inserted into a vein. The first dose of Herceptin you get takes about 90 minutes. After that, it only takes about 30 minutes to get the other doses of Herceptin, which are usually given weekly. If you have earlier stage disease and take Herceptin alone or as part of a regimen containing Adriamycin (chemical name: doxorubicin), Cytoxan (chemical name: cyclophosphamide), and Taxol (chemical name: paclitaxel), you receive it for a specific amount of time and then stop taking it.

DOSAGE GUIDELINES
• The recommended dosages of Herceptin are based on patient body weight.
- Initial loading dose: 4 mg/kg body weight
- Weekly subsequent doses: 2 mg/kg body weight
• To determine the correct number of milligrams of Herceptin needed for a given patient:
- Convert patient weight into kilograms: 2.2 lb =1 kg
- Insert patient weight in kilograms into the dosage equation below, using either 4 mg (loading dose) or 2 mg (subsequent doses) as the multiplier:

SIDE EFFECTS HERCEPTIN ( TRASTUZUMAB )
Herceptin causes flu-like symptoms in about 40% of the women who take it. These symptoms may include fever, chills, muscle aches, or nausea. These side effects generally become less severe after the first treatment. Other side effects, including low white or red blood cell counts, diarrhea, and infections, are seen in some women receiving Herceptin in combination with chemotherapy, but are rarely seen in women taking Herceptin alone.

1. Allergic reactions = This is a rare side effect of Herceptin. Signs of this include skin rashes and itching, wheezing, difficulty breathing, and breathlessness. You will be closely monitored during your treatment, but let your nurse or doctor know if you have any of these symptoms. To reduce the chance of developing an allergic reaction, antihistamines can be given before the infusion. The infusion can also be slowed down or stopped until the reaction is over.
2. Flu-like symptoms = This includes a high temperature (fever) and chills, shortly after the drug is given. These symptoms can be controlled or reduced with medicines, which your doctor can prescribe for you.
3. Tumour pain = Some people may experience mild pain in parts of the body to which the breast cancer has spread. Painkillers can be given to relieve this.
4. Diarrhoea = This can usually be controlled with medicine, but let your doctor know if it is severe or if it continues. It is important to drink plenty of fluids if you have diarrhoea.
5. Headaches = Let your doctor know if you have headaches while having treatment with Herceptin.
6. Effects on the heart = Herceptin may lead to some people having heart problems. For that reason it is recommended that Herceptin is not given to people with a history of heart disease or high blood pressure.