Sorafenib/Capecitabine Combo Fails to Meet Primary Endpoint in Breast Cancer Trial
Treated patients show no improvement in progression-free survival
A phase III trial of sorafenib (Nexavar, Bayer HealthCare/Onyx Pharmaceuticals) plus capecitabine (Xeloda, Roche) in patients with advanced breast cancer has failed to meet its primary endpoint of improving progression-free survival (PFS).
The RESILIENCE (TRial Comparing CapecitabinE in Combination With SorafenIb or PLacebo for Treatment of Locally Advanced or MetastatIc HER2–Negative Breast CancEr) study evaluated the efficacy and safety of sorafenib, a kinase inhibitor, in combination with capecitabine, an oral chemotherapeutic agent, compared with placebo plus capecitabine, in 537 patients with human epidermal growth factor receptor-2 (HER2)-negative breast cancer who were resistant to or had failed prior taxane therapy, and who were resistant to or had failed an anthracycline or for whom further anthracycline therapy was not indicated.
In addition to the trial’s primary endpoint of PFS, secondary endpoints included overall survival, the time to progression, the overall response rate, the disease control rate, the duration of response, patient-reported quality of life, and safety.
The patients were randomly assigned to receive 600 mg of oral sorafenib or matching placebo daily on a continuous schedule, in addition to 1,000mg/m2 of capecitabine twice daily for 14 days of a 21 day cycle.
In the U.S., Nexavar (sorafenib) is indicated for the treatment of unresectable hepatocellular carcinoma; advanced renal-cell carcinoma; and locally recurrent or metastatic, progressive, differentiated thyroid carcinoma that is refractory to radioactive iodine treatment.
In preclinical studies, sorafenib was shown to inhibit multiple kinases thought to be involved in both cell proliferation and angiogenesis — two important processes that enable cancer growth. These kinases include Raf kinase, VEGFR-1, VEGFR-2, VEGFR-3, PDGFR-B, KIT, FLT-3, and RET.