Data demonstrates comparable anti-tumor activity over marketed PD-L1 antibody in preclinical models of colon cancer and melanoma

PLEASANTON, CA, USA I October 30, 2017 I CBT Pharmaceuticals (CBT), a biopharmaceutical company focused on developing innovative oncology therapeutics harnessing the immune system and targeting specific molecular pathways to tame cancer, presented preclinical data demonstrating the safety and efficacy of its Programmed Death-Ligand 1 (PD-L1) antibody, CBT-502 (TQB2450), in stimulating IL-2 and Interferon gamma production, suppressing tumor growth and delaying tumor progression in preclinical models of colon cancer and melanoma. Data were presented in a poster at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics being held October 26–30, 2017 in Philadelphia, Pennsylvania.

“The in-vitro characteristics and in-vivo efficacy studies showing linear pharmacokinetics suggest that CBT-502 may provide benefit in a variety of tumor types,” said Sanjeev Redkar, Ph.D., President and Chief Executive Officer. “CBT-502’s significant sequence divergence in complementarity-determining regions compared to incumbent PD-L1 inhibitors, may offer a point of differentiation in the clinical setting.”

Presentation Highlights:

  • CBT-502 efficiently inhibited binding of PD-L1 with no binding to PD-L2, CD28, ICOS or CTLA4.
  • CBT-502 enhanced human T-cell activation, as shown by increased release of IL-2 and IFN-gamma and reduced T regulatory cells in the mixed lymphocyte assay.
  • In a humanized preclinical model expressing human PD-L1 and implanted with a colon adenocarcinoma (MC38) cell line and in a A375 human melanoma model, CBT-502 significantly inhibited tumor growth in a dose-dependent manner that was comparable to atezolizumab.
  • Pre-clinical pharmacodynamics and toxicology studies of CBT-502 demonstrated an effective pharmacological activity with a wide margin of safety.

“These studies support our commitment to advancing the clinical development of CBT-502 as an immuno-oncology therapy for a variety of cancers. Based on these findings, IND enabling studies will commence in 2018 and a Phase 1/2 combination study will be initiated in the second half of 2018 in Australia,” said Gavin Choy, EVP and Chief Operating Officer at CBT Pharmaceuticals.

CBT-502
CBT-502 is a novel humanized IgG1 monoclonal antibody targeting the Programmed Death-Ligand 1 (PD-L1) membrane receptor on T lymphocytes and other cells of the immune system. CBT-502 has a comparable efficacy profile in in-vitro and in-vivo studies to marketed anti-PD-L1 antibodies and has a no Fc receptor activity. The antibody is being developed by Chia Tai Tianqing (CTTQ) Pharmaceutical Group Co, Ltd. for commercialization in China. CBT Pharmaceuticals, Inc. retains marketing rights for rest of the world.

About CBT Pharmaceuticals
CBT Pharmaceuticals is a biopharmaceutical company focused on developing innovative oncology therapeutics harnessing the immune system and targeting specific molecular pathways to tame cancer. The company is advancing a pipeline of four development-stage assets. CBT-101, is an oral c-MET inhibitor targeting the epithelial to mesenchymal transition (EMT) pathway and CBT-102, an oral multi-targeted kinase inhibitor that targets uncontrolled growth signaling pathways. In addition, CBT has two novel humanized monoclonal antibodies – CBT-501, targeting the Programmed Death-1 (PD-1) membrane receptor of immune cells, as well as Programmed Death Ligand-1 (PD-L1) (CBT-502) that restores the body’s immune system to recognize and kill cancer cells. CBT is seeking partners for combination therapies with its PD-1 and PD-L1 antibodies. The company was founded in 2016 with headquarters in California. www.cbtpharma.com

SOURCE: CBT Pharmaceuticals