- Potential to Combine With Anti-CTLA-4, Anti-PD-1 and Other Immuno-Oncology Therapies
- IND Filing Remains on Track for 1H2016
“We believe that drugs targeting metabolic checkpoints have the potential to be transformational in the treatment of cancer. At Calithera, we are dedicated to researching and developing first-in-class therapies that could significantly advance the field of oncology. We have made significant progress on our CB-1158 program and remain on track to file an Investigational New Drug application (IND) in the first half of 2016,” said
Preclinical data will be presented in a poster titled, “CB-1158 Inhibits the Immuno-Oncology Target Arginase and Causes an Immune Mediated Anti-Tumor Response,” (Abstract #A195). CB-1158, a highly selective, orally bioavailable, small molecule inhibitor of human arginase with nanomolar potency, demonstrated single agent efficacy in animal models. Inhibition of tumor growth was accompanied by a rapid increase in the local concentration of arginine, and the induction of multiple pro-inflammatory changes in the tumor microenvironment. CB-1158, when administered with anti-CTLA-4, increased CD8+ T-cell infiltrates in the tumor. The addition of CB-1158 to anti-CTLA-4 and anti-PD-1, significantly inhibited tumor growth in a mouse model that was resistant to dual checkpoint inhibitor therapy. CB-1158 was well tolerated as a single agent and in combination with checkpoint inhibitors in animal studies.
Arginase is a critical immunosuppressive enzyme responsible for T-cell suppression. Arginase depletes arginine, a nutrient that is critical for the activation, growth and survival of the body’s cancer-fighting immune cells, known as cytotoxic T-cells. Arginase inhibitors can restore arginine levels and reverse this immunosuppressive effect of myeloid-derived suppressor cells (MDSCs). Myeloid cells are present in many human tumors and are correlated with poor prognosis. CB-1158 has the potential for anti-tumor activity in renal cell cancer, breast cancer, non-small cell lung cancer, acute myeloid leukemia, and other tumor types where arginase-secreting MDSCs are known to play an immunosuppressive role.
About Calithera Biosciences
Forward Looking Statements
This news release contains forward-looking statements by Calithera that involve risks and uncertainties. These statements include those related to the potential for CB-1158 to inhibit arginase, induce anti-cancer activity and combine with other immuno-oncology therapies that target T-cell activation, the timing of Calithera’s submission of an IND application to the
Jennifer McNealeyir@Calithera.com 650-870-1071