Eisai changes US E7389 filing schedule

Japanese drug major Eisai's US subsidiary has announced a change in the schedule for submission to the Food and Drug Administration of a New Drug Application for E7389 (eribulin mesylate) for third-line treatment of advanced breast cancer in patients who were pre-treated with anthracycline, taxane and capecitabine.

Eisai had planned to submit an NDA under Subpart H, based on Phase II clinical trial data, to seek accelerated approval for E7389 as a third-line breast cancer treatment (monotherapy), but is precluded from doing so, because the FDA cleared another drug for this specific indication last October. The company says it remains committed to advancing two Phase III clinical trials for E7389, which are ongoing in the USA and in Europe, Study 301 for second-line and Study 305 for third-line breast cancer treatment. The firm now plans to submit an NDA to the FDA with data from these trials and Phase II clinical trial data in fiscal year 2009-2010. In addition, Eisai says it is continuing to evaluate the compound as a potential treatment for a variety of other solid tumors, including non-small cell lung cancer, prostate cancer and sarcoma.

In a Phase II study of 299 patients with advanced breast cancer who had been heavily pre-treated, the drug has shown promising anti-tumor activity, with a response rate of 14.1% by investigator evaluation and 9.3% by independent radiologist evaluation. It has also been shown in the Phase II study to be generally well-tolerated, with the most common Grades 3 and 4 drug-related adverse events being 54% in neutropenia and 14% in leucopenia. Grade 3 peripheral neuropathy occurred in 6% of study participants and there were no Grade 4 events, the firm noted.