HRX-0233

HRX-0233 is a potent and selective small-molecule inhibitor of MAP2K4 (also known as MKK4), a kinase involved in the stress-activated protein kinase (SAPK) signaling pathway. It has demonstrated strong antitumor activity, particularly in KRAS-mutant cancers such as non-small cell lung cancer (NSCLC) and colon cancer. Preclinical studies show that while HRX-0233 alone has limited effects, it is highly synergistic with KRAS G12C inhibitors like sotorasib, preventing feedback activation of the MAP2K4-JNK-JUN pathway that can lead to drug resistance. The combination results in durable tumor shrinkage without apparent toxicity in animal models. This suggests potential for use as part of combination therapy strategies targeting KRAS-driven cancers[1][2][4][5][6][7].