Phase III follow-up of Abraxane (nab-paclitaxel) in breast cancer shows benefits of reduced dosage- Celgene

A follow-up to a Phase III trial demonstrated a lower dose of Abraxane (nab-paclitaxel), from Celgene, (125mg/m2/week) maintains efficacy in breast cancer and is less toxic than a higher dose (150mg/m2week) that was the starting point in the study. Both doses demonstrated improved efficacy compared to conventional paclitaxel.

Previous data demonstrated significant benefit for nab-paclitaxel for patients with early high-risk breast cancer when compared to conventional solvent-based paclitaxel. However, the optimal dose was in question. The updated results presented this year clearly demonstrate that the lower dose provides not only reduced side effects such as peripheral neuropathy, but better drug adherence. concludes the risk-benefit ratio was improved using nab-paclitaxel at the 125 mg dose with better drug adherence and relative total dose intensity, lower frequency of peripheral neuropathy and comparable pathological complete response (pCR). PCR after neoadjuvant treatment for breast cancer is a surrogate marker for long-term efficacy. In all patients, not just the triple negative cases, pCR was 41% at 125 mg, 32% at 150 mg and 29% for conventional paclitaxel.

Peripheral neuropathy grade 3/4 dropped from 15% in the 150 mg cohort to just 8% at the 125 mg dose level. Neuropathy was lowest in the paclitaxel cohort (3%) but, as noted, conventional paclitaxel was not as effective. Data were presented at the San Antonio Breast Cancer Symposium.