Abstract 2991: Triple combination of bevacizumab, anti-DLL4 (delta like ligand 4) and trebananib gives enhanced therapeutic effects in three xenograft tumor models

Abstract

Abstract Bevacizumab is a monoclonal antibody targeting VEGF that is clinically approved for the treatment of multiple indications in oncology, including colorectal, lung and renal cancer as well as glioblastoma. Clinical activity has also been demonstrated in breast and ovarian cancer as well, however, the time periods of benefit for all of these indications is in months (1-5). Multiple pathways are known to participate in the process of angiogenesis, and the limited effects of bevacizumab may represent the maximum activity of targeting just one of them. The purpose of the present study was to examine the effect of simultaneously targeting multiple angiogenic axes including angiopoietins 1 and 2, Dll4 and VEGF. Trebananib is a recombinant peptide-Fc fusion protein that selectively blocks the Tie2 interactions of both Ang1 and Ang2. Trebananib, as well as a recombinant antibody to Dll4 were produced at Amgen, Inc., Thousand Oaks, CA. Bevacizumab was purchased from a local pharmacy. These reagents were employed in the combination treatment of three different preclinical murine tumor models (U87, glioblastoma; MiaPaca and BxPC3, pancreatic carcinoma), one of which (BxPC3) was specifically selected for its relative resistance to VEGF/KDR inhibition. Harlan Athymic nu/nu female mice at 6-7 weeks of age were injected subcutaneously on the right flank with 5 x 106 tumor cells in the presence of Matrigel and treated when the tumors were approximately 300 mm3. The results, as supported by histomorphometric analysis (percent blood vessel area, viable tumor burden), demonstrate that under conditions of optimal biological dosing, the addition of trebananib to a two-way combination of bevacizumab and anti-Dll4 resulted in a statistically significant enhancement of therapeutic effect for the three-way combination, an observation made consistently over 3 different tumor models and 3 different dose levels of bevacizumab and anti-Dll4 (p = or < 0.0024; RMANOVA). Furthermore, the therapeutic effect in all three models approximated prolonged stasis, the ultimate theoretical goal of antiangiogenesis in the treatment of cancer. 1. NEJM, vol. 350, p. 2335, 2004. 2. NEJM, vol. 355, p. 2542, 2006. 3. Lancet, vol. 370, p. 2103, 2007. 4. NEJM, vol. 357, p. 2666, 2007. 5. J. Clin. Oncol., vol. 30, p. 2039, 2012. Citation Format: Bethany Mattson, Jodi Moriguchi, H. Toni Jun, Angela Coxon, Dave Cordover, Steve Kaufman, Jon Oliner, Charlie Starnes. Triple combination of bevacizumab, anti-DLL4 (delta like ligand 4) and trebananib gives enhanced therapeutic effects in three xenograft tumor models. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2991. doi:10.1158/1538-7445.AM2014-2991