Small molecule allosteric inhibitors of RORγt block Th17-dependent inflammation and associated gene expression in vivo.

Retinoic acid receptor-related orphan nuclear receptor (ROR) γt is a member of the RORC nuclear hormone receptor family of transcription factors. RORγt functions as a critical regulator of thymopoiesis and immune responses. RORγt is expressed in multiple immune cell populations including Th17 cells, where its primary function is regulation of immune responses to bacteria and fungi through IL-17A production. However, excessive IL-17A production has been linked to numerous autoimmune diseases. Moreover, Th17 cells have been shown to elicit both pro- and anti-tumor effects. Thus, modulation of the RORγt/IL-17A axis may represent an attractive therapeutic target for the treatment of autoimmune disorders and some cancers. Herein we report the design, synthesis and characterization of three selective allosteric RORγt inhibitors in preclinical models of inflammation and tumor growth. We demonstrate that these compounds can inhibit Th17 differentiation and maintenance in vitro and Th17-dependent inflammation and associated gene expression in vivo, in a dose-dependent manner. Finally, RORγt inhibitors were assessed for efficacy against tumor formation. While, RORγt inhibitors were shown to inhibit tumor formation in pancreatic ductal adenocarcinoma (PDAC) organoids in vitro and modulate RORγt target genes in vivo, this activity was not sufficient to delay tumor volume in a KP/C human tumor mouse model of pancreatic cancer.

Discovery of CC-90011: A Potent and Selective Reversible Inhibitor of Lysine Specific Demethylase 1 (LSD1).

Histone demethylase LSDl (KDMlA) belongs to the flavin adenine dinucleotide (FAD) dependent family of monoamine oxidases and is vital in regulation of mammalian biology. Dysregulation and overexpression of LSD1 are hallmarks of a number of human diseases, particularly cancers that are characterized as morphologically poorly differentiated. As such, inhibitors of LSD1 have potential to be beneficial as a cancer therapy. The most clinically advanced inhibitors of LSDl are covalent inhibitors derived from tranylcypromine (TCP). Herein, we report the discovery of a novel series of reversible and selective LSDl inhibitors. Exploration of structure-activity relationships (SARs) and optimization of ADME properties resulted in the identification of clinical candidate CC-90011. CC-90011 exhibits potent on-target induction of cellular differentiation in acute myeloid leukemia (AML) and small cell lung cancer (SCLC) cell lines, and antitumor efficacy in patient-derived xenograft (PDX) SCLC models. CC-90011 is currently in phase 2 trials in patients with first line, extensive stage SCLC (ClinicalTrials.gov identifier: NCT03850067).