In a nutshell
In this study researchers reviewed the adverse effects of the chemotherapy drug ixabepilone for patients with metastatic breast cancer and how these can be managed by reducing the dosage.
Some background
Ixabepilone (Ixempra) is a chemotherapy drug approved by the U.S. FDA as treatment for metastatic breast cancer (breast cancer that has spread to distant organs or tissues in the body) patients, when the cancer does not respond to other drugs. The standard dose of ixabepilone, alone or in combination with other chemotherapy drugs such as capecitabine (Xeloda), is 40 mg/m2 into the vein over 3 hours, every 3 weeks. It works by damaging and killing cancer cells and can increase patients’ survival. However, ixabepilone can also damage normal cells in the body, thus leading to adverse effects that can severely influence patients’ quality of life. Therefore, it is important to understand whether reducing the dosage of ixabepilone could also reduce its side effects.
Methods & findings
Researchers compared several recent studies that used ixabepilone for the treatment of patients with metastatic breast cancer. They found that the most common side effects were nerve damage, low white blood cells (cells which fight infections), and tiredness. Side effects of grade 3 or 4 (severe side effects than can be disabling or life-threatening) occurred in up to 73% of patients. When events of grade 3 or 4 occur, ixabepilone should either be stopped or have the dose reduced by 20% (from 40 mg/m2 to 32 mg/m2 or to 25 mg/m2). If stopped, ixabepilone treatment can be resumed at a 20% lower dose (32 mg/m2) once symptoms improve. Studies showed that reducing the dose of ixabepilone does not reduce its effectiveness against metastatic breast cancer. Side effects can also be reduced by giving ixabepilone as a lower (15-20 mg/m2), once-weekly dose, rather than the standard 40 mg/m2 dose once every 3 weeks. However, further studies are needed to assess whether a weekly schedule reduces the anti-cancer effects of ixabepilone.
The bottom line
In summary, many adverse effects of ixabepilone can be safely managed by reducing the dose by 20%, without influencing its cancer-fighting effects.
The fine print
This study was funded by Bristol-Myers Squibb, the manufacturer of ixabepilone.
What’s next?
Talk to your doctor before changing the dosage to any drugs.
Published By :
Clinical Breast Cancer
Date :
May 15, 2013
