Jiangsu HengRui Medicine Co. is developing SHR-117887, an orally active dipeptidyl peptidase-4 (CD26 antigen) inhibitor for the treatment of type 2 diabetes. SHR-117887 is a potent DPP-4 inhibitor that improves metabolic control and β-cell function in diabetic rodent models. SHR-117887 is in phase II clinical trials for the treatment of type 2 diabetes.

SNS 314 is a selective small molecule inhibitor of Aurora kinases A, B and C. The compound was being developed by Sunesis Pharmaceuticals for the treatment of cancer. Proliferating cells treated with SNS-314 bypass the mitotic spindle checkpoint and fail to undergo cytokinesis, leading to multiple rounds of endoreduplication and eventually cell death. SNS-314 inhibits tumor growth in a variety of preclinical models, and it was being tested in single agent Phase 1 studies in patients with advanced solid tumours.

Selonsertib, also known as GS-4997, is a small-molecule inhibitor of apoptosis signal-regulating kinase 1 (ASK1), which promotes inflammation, apoptosis and fibrosis in settings of increased oxidative stress associated with NASH pathogenesis. GS-4997 prevents the production of inflammatory cytokines, down-regulates the expression of genes involved in fibrosis, suppresses excessive apoptosis and inhibits cellular proliferation. GS-4997 is currently being evaluated in an ongoing Phase 2 study in patients with NASH and moderate to severe liver fibrosis.

CK-101 is an orally available third-generation and selective inhibitor of certain epidermal growth factor receptor (EGFR) activating mutations, including the resistance mutation T790M, with potential antineoplastic activity. Activating mutations in the tyrosine kinase domain of EGFR are found in approximately 20% of patients with advanced Non-Small Cell Lung Cancer (NSCLC). Compared to chemotherapy, first-generation EGFR inhibitors significantly improved ORR and progression-free survival in previously untreated NSCLC patients carrying EGFR mutations. However, tumor progression could develop due to resistance mutations, often within months of treatment with first-generation EGFR inhibitors. CK-101 designed to be highly selective against the T790M mutation while sparing wild-type EGFR, thereby improving tolerability and safety profiles. Compared to some other EGFR inhibitors, CK-101 may have therapeutic benefits in tumors with T790M-mediated drug resistance. This agent shows minimal activity against wild-type EGFR (WT EGFR) and does not cause dose-limiting toxicities that occur during the use of non-selective EGFR inhibitors, which also inhibit WT EGFR.

Famitinib, an orally active, small molecule, is a tyrosine kinase inhibitor against multiple targets, including vascular endothelial growth factor receptor 2/3, platelet-derived growth factor receptor, and stem cell factor receptor (c-kit). Jiangsu Hengrui Medicine Co is developing famitinib against a wide variety of advanced-stage solid cancers. Famitinib is participating in phase III clinical trials to evaluate its safety and efficacy in patients with advanced colorectal adenocarcinoma. The other phase III clinical trial for patients with non-squamous non-small cell lung cancer was terminated because of the difficulty in recruitment. In addition, the drug is involved in phase II clinical trials for the treatment of cervical cancer, endometrial cancer, fallopian tube cancer, gastrointestinal stromal tumors, nasopharyngeal cancer, and neuroendocrine tumors.

Crenolanib is an orally active, highly selective, small molecule, next generation inhibitor of platelet-derived growth factor receptor (PDGFR) tyrosine kinase. Crenolanib, manufactured by Arog Pharmaceuticals in Dallas, is taken orally with chemotherapy. The compound is currently being evaluated for safety and efficacy in clinical trials for various types of cancer, including acute myeloid leukemia (AML), gastrointestinal stromal tumor (GIST), and glioma. Crenolanib is an orally bioavailable, selective small molecule inhibitor of type III tyrosine kinases with nanomolar potencies against platelet-derived growth factor receptors (PDGFR) (isoforms PDGFRα and PDGFRβ) and Fms-related tyrosine kinase 3 (FLT3). Besides PDGFR and FLT3, crenolanib does not inhibit any other known receptor tyrosine kinase (RTK) (e.g. VEGFR and FGFR) or any other serine/threonine kinase (e.g., Abl, Raf) at clinically achievable concentrations. Preclinical trials have shown Crenolanib to be active in inhibiting both wild-type and mutant FLT3. Crenolanib is cytotoxic to the FLT3/ITD-expressing leukemia cell lines Molm14 and MV411, with IC50s of 7 nM and 8 nM, respectively. In immunoblots, crenolanib inhibited phosphorylation of both the wild-type FLT3 receptor (in SEMK2 cells) and the FLT3/ITD receptor (in Molm14 cells) in culture medium with IC50s of 1-3 nM. Importantly, the IC50 of crenolanib against the D835Y mutated form of FLT3 was 8.8 nM in culture medium. Furthermore, crenolanib had cytotoxic activity against primary samples that were obtained from patients who had developed D835 mutations while receiving FLT3 TKIs. In vitro, the IC50 of crenolanib for inhibition of FLT3/ITD in plasma was found to be 34 nM, indicating a relatively low degree of plasma protein binding. From pharmacokinetic studies of crenolanib in solid tumor patients, steady state trough plasma levels of roughly 500 nM were found to be safe and tolerable, suggesting that crenolanib could potentially inhibit the target in vivo. Crenolanib has no significant activity against c-KIT, which may be an advantage in that myelosuppression can be avoided.1Furthermore, there was no evidence of QTc prolongation in patients treated with crenolanib. In summary, crenolanib offers a number of advantages over other FLT3 TKIs. Clinical trials of crenolanib in AML patients with FLT3 activating mutations are being planned.