Nektar Therapeutics announced that the Independent Data Monitoring Committee (DMC) created to provide safety oversight for the company's pivotal clinical study for etirinotecan pegol (NKTR-102) has recommended continuation of the BEACON phase 3 trial, based upon the completion of a planned interim efficacy analysis in accordance with the DMC charter. The BEACON trial is evaluating NKTR-102 versus an agent of physician's choice for the treatment of locally recurrent or metastatic breast cancer, with a primary efficacy endpoint of overall survival. NKTR-102 is the first long-acting topoisomerase I-inhibitor designed to concentrate in tumor tissue, provide sustained tumor suppression throughout the entire chemotherapy cycle, and to reduce the peak exposures that are associated with toxicities of other cytotoxics.

The independent DMC performed the pre-defined interim efficacy analysis, which consisted of a review of ongoing efficacy and safety data, including 50% of patient events necessary to evaluate the primary endpoint of overall survival. In August 2013, the BEACON study completed enrollment of 852 patients with advanced breast cancer whose disease has progressed following treatment with anthracycline, taxane and capecitabine therapies (ATC). BEACON is a Phase 3, open-label, randomized, multicenter study of NKTR-102 which enrolled 852 women with locally recurrent or metastatic breast cancer, who have previously been treated with ATC.

The trial is being conducted at approximately 150 sites worldwide including North America, Western Europe, Russia and the Republic of Korea. Nearly half of the patients enrolled in BEACON were located in North America. Patients were randomized on a 1:1 basis to receive 145 mg/m2 of single-agent NKTR-102 once every three weeks or a single agent of physician's choice.

The physician's choice agents include: ixabepilone, vinorelbine, gemcitabine, eribulin, or a taxane. Randomization was stratified by geographic region, prior use of eribulin and receptor status. The study is also evaluating specific biomarker data to assess correlation with objective tumor response rates, progression-free survival, overall survival and selected toxicities.