Abraxis BioScience: Abraxane Will Face Strong Competition in Europe

Abraxane, a novel reformulation of paclitaxel, will be a welcome additional treatment option for metastatic breast cancer patients in Europe. Although uptake of the drug could be limited due to competition from well-established therapies, Abraxis could benefit from collaborating with a larger oncology player to effectively market Abraxane.

Abraxis BioScience’s Abraxane has received marketing approval in the EU as a second-line treatment for metastatic breast cancer in patients who are not suitable candidates for treatment with an anthracycline-containing regimen. Abraxis plans to launch the drug in the EU in mid-2008.

Abraxane is a nanoparticle protein-bound formulation of paclitaxel, a cytotoxic drug which is commonly used for the treatment of breast cancer. The drug, which is administered intravenously, uses the human protein albumin to deliver the active ingredient paclitaxel. This means that the side effects caused by solvents used in traditional formulations of paclitaxel can potentially be avoided, allowing a higher dose of the active ingredient to be delivered.

The approval was based on data from a Phase III trial in which Abraxane was compared to the traditional solvent-based formulation of paclitaxel as a second-line treatment for breast cancer. The median progression-free survival for patients who received Abraxane was 20.6 weeks, compared to 16.1 weeks for patients who received solvent-based paclitaxel. Overall survival was 56.4 weeks for Abraxane compared to 46.7 weeks for solvent-based paclitaxel.

The superior efficacy of Abraxane arises largely from the higher dose possible with this formulation of paclitaxel. However, the higher dose also means that grade 3 neuropathy was more common in the Abraxane arm.

Despite the improvement in treatment outcome, there are several hurdles which need to be overcome if Abraxane is to achieve a significant level of market penetration in this setting. Abraxane will face stiff competition when pitted against generic versions of paclitaxel, which are considerably cheaper and have been available for several years. Further competition in this setting comes from Roche’s Xeloda (capecitabine) which has the advantage of a more convenient oral formulation.

A large marketing effort is therefore needed in order for Abraxane to secure a larger market share. To achieve this, Abraxis would benefit from the help of AstraZeneca, a big player in the oncology market. AstraZeneca currently holds rights to co-promote the drug in the US and may also choose to co-promote the drug in the EU. This assistance would be particularly important if the drug is eventually launched in the first-line setting.