CPI203

CPI203 is a **potent, selective, and competitive small molecule inhibitor of BET (bromodomain and extra-terminal) proteins**, in particular targeting BRD4[3][5]. It acts by blocking the recruitment of BET proteins, especially BRD4, to chromatin, suppressing transcriptional programs driven by oncogenic factors such as MYC[1][3]. CPI203 has demonstrated **antitumor effects in vitro and in vivo** across multiple cancer models, including multiple myeloma, mantle cell lymphoma, pancreatic neuroendocrine tumors, and glioma[1][2][3][4][6]. Notably, it can synergize with other agents (e.g., lenalidomide, dexamethasone, bortezomib, rapamycin) to enhance antitumor activity—even in drug-resistant cancer cell lines[1][2][3][7]. Oral and intraperitoneal dosing have shown favorable bioavailability and efficacy in preclinical animal models[1]. The development and provision of CPI203 is attributed to Constellation Pharmaceuticals[1].

Other names

(s)-2-(4-(4-chlorophenyl)-2,3,9-trimethyl-6h-thieno[3,2-f][1,2,4]triazolo[4,3-a][1,4]diazepin-6-yl)acetamide1446144-04-2CHEMBL4303293CHEMBL-4303293CHEMBL 4303293