The Board of Directors of Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. announced that key product A400, a small molecule rearranged during transfection (RET) kinase inhibitor program (also known as KL590586 or EP0031), has been granted Fast Track designation by the United States Food and Drug Administration (FDA) for the treatment of RET fusion-positive non-small cell lung cancer (NSCLC). A400 (EP0031) is a second-generation selective RET inhibitor (SRI) with broad activity against common RET fusions and mutations. In preclinical studies, A400 (EP0031) demonstrated favourable inhibitory activity against key RET kinases in-vitro and in-vivo.

A400 (EP0031) also demonstrated good penetration of the blood brain barrier in animal models. Data shared at the 2023 American Society of Clinical Oncology (ASCO) Annual Meeting on A400 (EP0031) showed promising anti-tumor efficacy in patients with advanced RET+ solid tumors, highlighted by ORR of 80.8% and 69.7% for 1L and 2L+ advanced RET+ NSCLC, respectively, based on results from its ongoing phase 1/2 trial. In both cases, DCR of over 96% were reported.

At present, the Company is conducting A400 (EP0031) pivotal clinical study in China for RET- positive NSCLC.