MP0250, a VEGF and HGF neutralizing DARPin ® molecule shows high anti-tumor efficacy in mouse xenograft and patient-derived tumor models

// Ulrike Fiedler 1 , Savira Ekawardhani 1 , Andreas Cornelius 1 , Pat Gilboy 1, 2 , Talitha R. Bakker 1, 3 , Ignacio Dolado 1, 4 , Michael T. Stumpp 1 and Keith M. Dawson 1 1 Molecular Partners AG, Schlieren, Switzerland 2 Horizon Pharma, Dublin, Ireland 3 Amgen (Europe) GmbH, Zug, Switzerland 4 Roche, Basel, Switzerland Correspondence to: Keith M. Dawson, email: info@molecularpartners.com Keywords: VEGF, HGF, serum albumin, DARPin ® , patient-derived xenograft Received: July 13, 2017      Accepted: September 21, 2017      Published: October 11, 2017 ABSTRACT Background: The VEGF/VEGFR and the HGF/cMET pathways are key mediators of the interplay of tumor cells and their microenvironment. However, inhibition of VEGF has been shown to produce only limited clinical benefit and inhibition of the activation of cMET by HGF has not translated into clinical benefit in pivotal trials. MP0250, a DARPin ® molecule that specifically inhibits both VEGF and HGF has been developed to explore the clinical potential of dual inhibition of these pathways. Results: MP0250 binding to VEGF and HGF inhibited downstream signalling through VEGFR2 and cMET resulting in inhibition of proliferation of VEGF- and HGF-dependent cells. Antitumor activity was demonstrated in VEGF- and HGF-dependent xenograft and syngeneic models with activity superior to that of individual VEGF- and HGF-blocking DARPin ® molecules. Combination therapy studies showed potentiation of the antitumor activity of chemotherapy and immunotherapy agents, including an anti-PD1 antibody. Materials and Methods: Potency of MP0250 was assessed in cellular models and in a variety of xenograft models as monotherapy or in combination with standard-of-care drugs. Conclusions: Dual inhibition of VEGF and HGF by MP0250 produced powerful single agent and combination antitumor activity. This, together with increasing understanding of the role of the HGF/cMET pathway in resistance to VEGF (and other agents), supports testing of MP0250 in the clinic.