Targeted Therapy

What is targeted therapy?
Targeted therapy is cancer treatment that uses drugs to attack unique aspects of cancer cells with little harm to healthy cells.  Targeted therapies can work by:

• blocking the process that changes normal cells into cancer, thereby stopping the abnormal growth behavior of a tumor.
• preventing the formation of blood vessels that bring nutrients to the tumor.

What targeted therapies are available for pancreatic cancer?
In November 2005, the United States Food and Drug Administration (FDA) approved a targeted therapy drug, erlotinib (Tarceva®) in combination with the chemotherapy drug gemcitabine (Gemzar®), for use in advanced pancreatic cancer that cannot be removed surgically. 

Erlotinib is currently the only FDA approved targeted therapy for pancreatic cancer.  Most targeted cancer therapies are still under investigation in the laboratory or in clinical trials.  Clinical trials are research studies that are done to investigate new treatments through the observation of patients.  Since all cancers are different, a drug that is already approved by the FDA for the treatment of one type of cancer may not be approved to treat pancreatic cancer unless it proves effective through the clinical trials process.

How does erlotinib (Tarceva®) work?
Erlotinib (Tarceva®) targets a protein called the Human Epidermal Growth Factor Receptor 1, also referred to as HER1 and EGFR.  The EGFR protein is found in abnormally high levels on the surface of some pancreatic cancer cells.  By targeting EGFR, erlotinib blocks the growth of the cancerous cells.  This targeted therapy drug is often prescribed along with gemcitabine (Gemzar®) for patients with locally advanced and metastatic pancreatic cancer.

Is targeted therapy given with other treatments?
Erlotinib (Tarceva®) is FDA approved to treat pancreatic cancer in combination with gemcitabine (Gemzar®).  Targeted therapies in pancreatic cancer clinical trials are generally tested in combination with chemotherapy and/or other treatment(s) such as surgery.

Why are targeted therapies used?
Since targeted therapies attack specific receptors on some cancer cells, they generally do not harm healthy cells.  This is important as it reduces the side effects associated with the drug.  Targeted cancer therapies may create fewer side effects than other available treatments because their effects are directed at disabling or destroying only tumor cells while leaving healthy cells alone. Also, targeted therapies may someday provide doctors with a way to tailor cancer treatment to the unique tumor properties in each individual patient.

How is erlotinib (Tarceva®) administered?
Erlotinib (Tarceva®) is a pill that is usually taken once per day.  To reduce the chance of developing side effects, erlotinib (Tarceva®) should not be taken with food.  Take the pill at least one hour before or two hours after eating.  Grapefruits and grapefruit juice should be avoided because they may reduce the effectiveness of this targeted therapy.  Be sure to inform your doctor of any other medications and nutritional supplements (including vitamins, herbal teas, and other natural products) you are taking.  These substances may interact with the effectiveness of erlotinib (Tarceva®).

What are the side effects of Tarceva®?
Like all medications, patients taking erlotinib (Tarceva®) may experience side effects.  The most common side effects are fatigue, rash, nausea, loss of appetite, and diarrhea. 

If feeling fatigued, it is recommended that the patient take short rests throughout the day and engage in light to moderate exercise.  Schedule five to six meals each day with light snacks in between.  Maintain adequate hydration and avoid drinks containing caffeine such as coffee, tea, and sodas.

The acne-like rash that many patients experience on their face or body associated with erlotinib (Tarceva®) generally appears within the first 10 days of treatment.  Patients should use mild soap and water followed by an alcohol-free moisturizer to care for the affected areas.  Avoid exposure to direct sunlight and use of over-the-counter acne medications.  The doctor may prescribe an antibiotic to help alleviate the rash.

Loss of appetite, nausea, and vomiting can be minimized by eating small, frequent meals or snacks throughout the day.  Try cool foods since they have fewer odors and may be more easily digested than hot foods.  Limit the amount of fluid the patient drinks with meals.  Slowly sip peppermint or ginger tea, ginger ale, or other cold, clear, caffeine-free beverages.  Light to moderate exercise can help stimulate the appetite.  In addition, the doctor can prescribe anti-emetic (anti-nausea) medications.

Diarrhea generally appears within the first two weeks of treatment with erlotinib (Tarceva®).  Diarrhea can cause dehydration, so be sure to drink six to eight cups of mild, clear, caffeine-free  liquids throughout the day to replace fluid loss.  Replace lost sodium and potassium by consuming soup, crackers, pretzels, bananas, peeled potatoes, fruit juices or sports drinks.

The severity of side effects will vary depending on the dosage and length of treatment.  The doctor and patient must often balance possible side effects with potential benefits of treatment.  It is important to keep the doctor informed of any side effects or pain.  Side effects are individual and may not occur in each person receiving treatment.  The doctor can only make changes in treatment or treat side effects if he or she is informed by the patient.

The information and services provided by the Pancreatic Cancer Action Network, Inc. are for informational purposes only.  The information and services are not intended to be substitutes for professional medical advice, diagnosis or treatment.  If you are ill, or suspect that you are ill, see a doctor immediately!  The Pancreatic Cancer Action Network does not recommend nor endorse any specific physicians, products or treatments even though they may be mentioned on this site.  080923