Weekly paclitaxel produced fewer toxicities than biweekly schedule

  • June 13, 2013

CHICAGO — Weekly dosing of paclitaxel and standard biweekly dosing resulted in nearly identical PFS among women with higher-risk early-stage breast cancer who had undergone surgery, according to results of a phase 3 clinical trial presented at the ASCO Annual Meeting.

However, adverse effects were more common with the biweekly dosing, indicating that a weekly dosing schedule could be preferred.

G. Thomas Budd, MD 

G. Thomas Budd

“Our results suggest that either regimen will give a good outcome, but the weekly schedule seems to result in better quality of life for patients, causing less muscle and bone pain and allergic reactions,” G. Thomas Budd, MD, a medical oncologist in the department of solid tumor oncology at the Cleveland Clinic, said in a press release. “The findings provide assurance that women can choose the lower-dose therapy without sacrificing their chances of survival.”

Budd and colleagues assigned 3,294 patients with node-positive and high-risk node-negative surgery-candidate breast cancer to either paclitaxel at 80 mg/m2 once a week for 12 weeks or standard-dose paclitaxel at 175 mg/m2 every 2 weeks for 12 weeks.

Patients in the standard-dose treatment group received pegfilgrastim (Neulasta, Amgen) supportive care to boost white blood cell counts.

Results showed the dosing schedules were associated with comparable 5-year PFS rates — 82% for the weekly regimen vs. 81% for biweekly.

However, researchers noted significant differences in the toxicity profiles. The biweekly schedule was associated with higher incidence of allergic reactions (1.4% vs. 0.6%), skin toxicities (2.7% vs. 1.9%) and musculoskeletal pain (11% vs. 3%) than the weekly schedule.

The incidence of neurologic toxicity — including numbness, tingling and pain of the fingers and toes — also was higher in the biweekly regimen (17% vs. 10%), but this disparity could have been less significant if the patients had received only four cycles of bi-weekly regimen rather than six cycles.

 

For more information:

Budd GT. Abstract #CRA1008. Presented at: ASCO Annual Meeting; May 31-June 4, 2013; Chicago.

Disclosure: The researchers report consulting/advisory positions with and research funding/honoraria from Amgen, Genentech, Novartis and Roche.

Perspective

Andrew D. Seidman

  • The current trial demonstrates that weekly paclitaxel dosing and every 2 weeks dosing were equally effective in preventing breast cancer progression. However, weekly dosing caused less toxicity and should ultimately be associated with lower cost due to less use of granulocyte colony–stimulating factor. While some oncologists have already been using the weekly schedule for adjuvant therapy, these results will motivate many doctors, including myself, to use weekly dosing.

    • Andrew D. Seidman, MD
    • Medical oncologist
      Breast Cancer Medicine Service
      Memorial Sloan-Kettering Cancer Center