A study has found that getting Taxol (chemical name: paclitaxel) at a lower dose weekly offers the same benefits as getting a higher dose every 2 weeks.
The study, “Comparison of two schedules of paclitaxel as adjuvant therapy for breast cancer,” was presented at the 2013 American Society of Clinical Oncology Annual Meeting.
The study was originally looking at two different regimens of a very common chemotherapy combination used to treat breast cancer: Adriamycin (chemical name: doxorubicin) and Cytoxan (chemical name: cyclophosphamide), followed by Taxol. This combination often is abbreviated as AC-T.
The two parts of the regimen – the Adriamycin-Cytoxan and the Taxol – are given on either a weekly, low-dose schedule or an every-two week schedule with a higher dose. The researchers wanted to see if one schedule offered more benefits than the other.
So the researchers planned to randomly assign 3,250 women diagnosed with stage I, stage II, or stage III breast cancer to receive either:
- a higher dose of Adriamycin and Cytoxan plus a granulocyte-colony-stimulating factor every 2 weeks
- a lower dose of Adriamycin and Cytoxan plus a granulocyte-colony-stimulating factor every week
A granulocyte colony stimulating factor, such as Neupogen (chemical name: filgrastim) or Neulasta (chemical name: pegfilgrastim), helps the body make more white blood cells and is used to reduce the risk of infection during chemotherapy treatment.
Each group was then split into two other groups that were randomly assigned to get either:
- a higher dose of Taxol plus granulocyte-colony-stimulating factor every 2 weeks
- a lower dose of Taxol every week with no granulocyte-colony-stimulating factor
Both groups were treated with Taxol for 12 weeks.
After about 2,700 women were enrolled in the study, the results showed that the higher dose of Adriamycin and Cytoxan plus granulocyte stimulating factor was better and all the women were switched over to that regimen. The women were still getting either a higher or lower dose of Taxol – that part of the study continued.
The researchers found that there was no difference in overall survival between the two Taxol groups. In other words, no matter which Taxol regimen the women were on, they all lived about the same time.
The researchers also found that both Taxol groups had similar rates of severe side effects, but the types of side effects were different:
- women on lower-dose, weekly Taxol had more blood-related side effects, such as low white blood cell counts
- women on higher-dose, every-2-week Taxol had more allergic reactions, bone pain, and neuropathy
Overall, the researchers said that weekly Taxol is less toxic for most women. They also pointed out that because the lower-dose, weekly Taxol is given without granulocyte-colony-stimulating factor, it costs less than the higher dose given every 2 weeks.
Because either Taxol regimen offers the same benefits, this study suggests that doctors can now decide on a regimen based on other factors, such as side effects.
If chemotherapy that includes Taxol is going to be part of your treatment plan, you may want to talk to your doctor about this study. Ask which treatment schedule is recommended for you and why it’s recommended.
In the Breastcancer.org Chemotherapy section you can learn about how chemotherapy works, when it’s used, and the combinations that might be used.