Bayer and Amgen’s Onyx Pharmaceuticals subsidiary have suffered a setback with the failure of a late-stage trial of their oncology blockbuster Nexavar plus Roche’s chemotherapy Xeloda in patients with advanced breast cancer.

Data from the study, called RESILIENCE, compared Nexavar (sorafenib) and Xeloda (capecitabine) with placebo plus Xeloda, in patients with HER2 negative breast cancer who are resistant to or have failed prior taxane, and are resistant to or have failed an anthracycline. The drug combo did not meet its primary endpoint of improving progression-free survival; detailed analyses will be presented at an upcoming scientific congress.

Joerg Moeller, Bayer HealthCare’s head of global development, said that the firms are disappointed there was no improvement in PFS and “while the primary endpoint of this trial was not met, the results do not affect the currently approved indications for Nexavar”.

In Europe, Nexavar is approved for liver, kidney and thyroid cancers.