TH: Paclitaxel and trastuzumab

TH (paclitaxel and trastuzumab) is a chemotherapy regimen used to treat HER2-positive breast cancer. It is a combination of two medicines:

• Paclitaxel (Taxol) – a type of chemotherapy medicine called a taxane
• Trastuzumab (Herceptin) – a type of targeted therapy called a monoclonal antibody

Sometimes this regimen is offered with another taxane, docetaxel (Taxotere), instead of paclitaxel. It would still be called TH. Ask your providers to explain why they recommend one taxane over another.

How TH works

Paclitaxel works by damaging the structure or the “skeleton” that supports cancer cells. This stops the cancer cells from growing and dividing. Docetaxel (Taxotere) works in a similar way and is sometimes used instead of paclitaxel.

Trastuzumab works by attaching to the HER2 proteins on the surface of HER2-positive cancer cells, and blocks the signals that cause the cancer cells to multiply.

Who gets TH

TH may be used to treat stage I and small stage II HER2- positive breast cancers that have not traveled to the lymph nodes. TH is given after surgery as adjuvant therapy. It can also be used to treat metastatic HER2-positive breast cancer.

You and your doctor will discuss the best chemotherapy treatment for your situation.

How TH is given

TH is usually given by vein into your hand or arm once a week for 12 weeks. This is typically followed by 9 months of treatment with trastuzumab alone, given either weekly or once every 3 weeks.

Side effects and things to remember

Different medicines have different side effects. You may not have every side effect related to each medicine of the combination therapy.

TH tends to cause fewer serious side effects than other combination regimens for HER2-positive breast cancer that contain multiple chemotherapy medicines plus trastuzumab. Side effects of TH may include:

• Allergic reaction
• Anemia, or low red blood cell count
• Diarrhea
• Fatigue
• Hair loss
• Neuropathy, numbness or tingling in the hands or feet
• Neutropenia, or low white blood cell count, which can make infections more likely

Heart problems are a rare but serious side effect of trastuzumab. These include congestive heart failure, when the heart muscle weakens and doesn’t pump blood well. Your doctor will check your heart before you start treatment and every several months during treatment. Be sure to tell your doctor if you have ever had heart problems.

Also tell your doctor about any medicines you are taking, including vitamins, herbal supplements, and over-the counter-medicines, to make sure they will not interfere with your chemotherapy treatment.

Contact your doctor right away if you develop a fever or other symptoms of an infection such as a sore throat or chills.

Talk to your doctor, pharmacist or nurse about all your side effects so that they can help you manage them. You can also go to our section on Side effects for more information.