Amgen's 1st Phase 3 Trial For Trebananib Reveals Disappointing Results

Amgen announced secondary endpoint results from the TRINOVA-1 trial of trebananib in women with recurrent ovarian cancer. The company stated in a press release that trebananib plus paclitaxel did not demonstrate a statistically significant improvement in overall survival vs. a placebo plus paclitaxel. The first of three Phase 3 trials, TRINOVA-1 did meet its primary endpoint of progression-free survival (PFS), reported in June 2013.

Sean E. Harper, M.D., executive VP of Research and Development at Amgen, said, "While the overall survival results of the TRINOVA-1 study are disappointing, this study is the first of three Phase 3 trials designed to evaluate the safety and efficacy of trebananib in patients with ovarian cancer. We continue to explore the potential of trebananib's novel anti-tumor mechanism of action in other cancer settings."

Trebananib

Trebananib is a peptibody that inhibits the angiopoietin axis, involved in growing new blood vessels. The agent binds to angiopoietin-1 and -2 (Ang1 and Ang2), thereby affecting vessel quality and vessel quantity. By inhibiting the angiopoietin axis and the angiopoietins, lymphangiogenesis and the formation of new lymphatic vessels is limited, thereby forestalling cell proliferation and tumor metastasis.

Trebananib Study

The Phase 3 TRINOVA-1 trial of trebananib in women was started in 2010 and was conducted in multiple countries. The study evaluated 900 women with recurrent partially platinum-sensitive or -resistant (platinum-free interval of 12 months or less) epithelial ovarian, primary peritoneal, or fallopian tube cancer. Patients took trebananib plus paclitaxel or a placebo plus paclitaxel. The results did not demonstrate a statistically significant improvement in overall survival. Patients in the trebananib arm experienced a median overall survival of 19.3 months vs. 18.3 months in the control arm. In median progression-free survival, the trebananib arm was 7.2 months vs. 5.4 months in the control arm. Investigators found no new safety issues.

Another trial (TRINOVA-2) is due to release results by the end of 2014. Results from another Phase 3 trebananib trial is expected in 2015. Amgen is also studying trebananib plus pegylated liposomal doxorubicin (PLD) in epithelial ovarian, primary peritoneal, or fallopian tube cancer as well as trebananib in combination with paclitaxel and carboplatin.

Amgen Activities

While the trebananib results may be disappointing, Amgen may have some other issues to address. Wall Street investors are pressuring the company to split up. The Wall Street Journal reports that Amgen has filed a lawsuit against Sandoz, who is trying to market an Amgen drug, Neupogen, as a biosimilar.