Abstract 1041: HBI-2376, HUYABIO clinical stage SHP2 inhibitor, possess robust in vitro potency and in vivo efficacy in several preclinical tumor models carrying KrasG12C or EGFR mutations

Abstract SHP2 (Src homology region 2-containing protein tyrosine phosphatase 2) is an attractive target in oncology drug development due to its dual roles on the direct growth and proliferation of cancer cells and also acting as an immune checkpoint molecule to suppress tumor immunity. HBI-2376 is an orally bioavailable selective SHP2 inhibitor that is being developed for the treatment of solid tumors harboring KRAS or EGFR mutations, such as non-small cell lung cancer (NSCLC) and colorectal cancer (CRC). Additionally, HBI-2376 has the potential to suppress tumor growth via induction of the activity of immune infiltrating cells in the TME (tumor microenvironment). In a head-to-head comparison, in vitro studies showed greater potency of HBI-2376 to inhibit cell proliferation in a variety of cancer cell lines compared to other SHP2 inhibitors such as TNO-155 (Novartis AG) and RMC-4550 (Revolution Medicines). Consistently, HBI-2376 found to be more efficacious in tumor growth inhibition than TNO-155 and RMC-4550 in NCI-H1975L858R_T790M_C797S osimertinib-resistant cell line and other tumor models. In addition to xenograft models, we tested efficacy of HBI-2376 as single agent or in combination with anti-PD1 mAb in MC38 CRC syngeneic model. Consistent with xenograft data, HBI-2376 showed greater efficacy in tumor growth inhibition vs. TNO-155 and RMC-4550 both as single agent and in combination therapy. IHC data showed reduction in infiltration of M2 macrophages (F4/80+Arg1+) in the HBI-2376 treated tumors suggesting a MoA for its greater efficacy in MC38 model. Furthermore, Western blotting showed inhibition of p-ERK and DUSP6 in HBI-2376 treated cells indicative of a biomarker of response to the therapy. These findings, along with a positive safety profile led to HBI-2376 IND clearance by FDA and suggested promising responses in NSCLC or CRC patients in the forthcoming clinical studies. Citation Format: Farbod Shojaei, Farbod Shojaei, Jill M. Ricono, Che Fang, Fairooz Kabbinavar, Bob Goodenow, Mireille Gillings. HBI-2376, HUYABIO clinical stage SHP2 inhibitor, possess robust in vitro potency and in vivo efficacy in several preclinical tumor models carrying KrasG12C or EGFR mutations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1041.