Preclinical characterization of CPL304110 as a potent and selective inhibitor of fibroblast growth factor receptors 1, 2, and 3 for gastric, bladder, and squamous cell lung cancer.

Fibroblast Growth Factor Receptors (FGFRs) are a family of receptor tyrosine kinases expressed on a plethora of cell membranes. They play crucial roles in both embryonic development and adult tissue functions. There is an increasing amount of evidence that FGFR-mediated oncogenesis is mainly related to gene amplification, activating mutations, or translocation in tumors of various histological types. Dysregulation of FGFRs has been implicated in a wide variety of neoplasms, such as bladder, gastric, and lung cancers. Given their functional significance, FGFRs emerge as promising targets for cancer therapy. Here, we introduce CPL304100, an innovative and highly potent FGFR1-3 kinase inhibitor demonstrating excellent in vitro biological activity. Comprehensive analyses encompassed kinase assays, cell line evaluations, PK/PD studies surface plasmon resonance studies, molecular docking, and in vivo testing in mouse xenografts. CPL304110 exhibited a distinctive binding profile to FGFR1/2/3 kinase domains, accompanied by a good safety profile and favorable ADMET parameters. Selective inhibition of tumor cell lines featuring active FGFR signaling was observed, distinguishing it from cell lines lacking FGFR aberrations (FGFR1, 2, and 3). CPL304110 demonstrated efficacy in both FGFR-dependent cell lines and patient-derived tumor xenograft (PDTX) in vivo models. Comparative analyses with FDA-approved FGFR inhibitors, erdafitinib and pemigatinib, revealed certain advantages of CPL304110 in both in vitro and in vivo assessments. Encouraging preclinical results led the way for the initiation of a Phase I clinical trial (01FGFR2018; NCT04149691) to further evaluate CPL304110 as a novel anticancer therapy.

A PDE10A inhibitor CPL500036 is a novel agent modulating striatal function devoid of most neuroleptic side-effects.

Background: Phosphodiesterase 10A (PDE10A) is expressed almost exclusively in the striatum and its inhibition is suggested to offer potential treatment in disorders associated with basal ganglia. We evaluated the selectivity, cytotoxicity, genotoxicity, pharmacokinetics and potential adverse effects of a novel PDE10A inhibitor, CPL500036, in vivo. Methods: The potency of CPL500036 was demonstrated by microfluidic technology, and selectivity was investigated in a radioligand binding assay against 44 targets. Cardiotoxicity in vitro was evaluated in human ether-a-go-go related gene (hERG)-potassium channel-overexpressing cells by the patch-clamp method and by assessing key parameters in 3D cardiac spheroids. Cytotoxicity was determined in H1299, HepG2 and SH-SY5Y cell lines. The Ames test was used for genotoxicity analyses. During in vivo studies, CPL500036 was administered by oral gavage. CPL500036 exposure were determined by liquid chromatography-tandem mass spectrometry and plasma protein binding was assessed. The bar test was employed to assess catalepsy. Prolactin and glucose levels in rat blood were measured by ELISAs and glucometers, respectively. Cardiovascular safety in vivo was investigated in dogs using a telemetry method. Results: CPL500036 inhibited PDE10A at an IC50 of 1 nM, and interacted only with the muscarinic M2 receptor as a negative allosteric modulator with an IC50 of 9.2 µM. Despite inhibiting hERG tail current at an IC25 of 3.2 µM, cardiovascular adverse effects were not observed in human cardiac 3D spheroids or in vivo. Cytotoxicity in vitro was observed only at > 60 µM and genotoxicity was not recorded during the Ames test. CPL500036 presented good bioavailability and penetration into the brain. CPL500036 elicited catalepsy at 0.6 mg/kg, but hyperprolactinemia or hyperglycemic effects were not observed in doses up to 3 mg/kg. Conclusion: CPL500036 is a potent, selective and orally bioavailable PDE10A inhibitor with a good safety profile distinct from marketed antipsychotics. CPL500036 may be a compelling drug candidate.

Design, Synthesis, and Development of pyrazolo[1,5-a]pyrimidine Derivatives as a Novel Series of Selective PI3Kδ Inhibitors: Part I-Indole Derivatives.

Phosphoinositide 3-kinase δ (PI3Kδ), a member of the class I PI3K family, is an essential signaling biomolecule that regulates the differentiation, proliferation, migration, and survival of immune cells. The overactivity of this protein causes cellular dysfunctions in many human disorders, for example, inflammatory and autoimmune diseases, including asthma or chronic obstructive pulmonary disease (COPD). In this work, we designed and synthesized a new library of small-molecule inhibitors based on indol-4-yl-pyrazolo[1,5-a]pyrimidine with IC50 values in the low nanomolar range and high selectivity against the PI3Kδ isoform. CPL302253 (54), the most potent compound of all the structures obtained, with IC50 = 2.8 nM, is a potential future candidate for clinical development as an inhaled drug to prevent asthma.

CPL207280, a Novel G Protein-Coupled Receptor 40/Free Fatty Acid Receptor 1-Specific Agonist, Shows a Favorable Safety Profile and Exerts Antidiabetic Effects in Type 2 Diabetic Animals.

G protein-coupled receptor (GPR) 40 is a free fatty acid receptor mainly expressed in pancreatic ß-cells activated by medium- and long-chain fatty acids and regulating insulin secretion via an increase in cytosolic free calcium ([Ca2+]i). Activation of GPR40 in pancreatic ß-cells may improve glycemic control in type 2 diabetes through enhancement of glucose-stimulated insulin secretion. However, the most clinically advanced GPR40 agonist-TAK-875 (fasiglifam)-was withdrawn from phase III because of its hepatotoxicity resulting from the inhibition of pivotal bile acid transporters. Here, we present a new, potent CPL207280 agonist and compare it with fasiglifam in numerous in vitro and in vivo studies. CPL207280 showed greater potency than fasiglifam in a Ca2+ influx assay with a human GPR40 protein (EC50 = 80 vs. 270 nM, respectively). At the 10 µM concentration, it showed 3.9 times greater enhancement of glucose-stimulated insulin secretion in mouse MIN6 pancreatic ß-cells. In Wistar Han rats and C57BL6 mice challenged with glucose, CPL207280 stimulated 2.5 times greater insulin secretion without causing hypoglycemia at 10 mg/kg compared with fasiglifam. In three diabetic rat models, CPL207280 improved glucose tolerance and increased insulin area under the curve by 212%, 142%, and 347%, respectively. Evaluation of potential off-target activity (Safety47) and selectivity of CPL207280 (at 10 µM) did not show any significant off-target activity. We conclude that CPL207280 is a potent enhancer of glucose-stimulated insulin secretion in animal disease models with no risk of hypoglycemia at therapeutic doses. Therefore, we propose the CPL207280 compound as a compelling candidate for type 2 diabetes treatment. SIGNIFICANCE STATEMENT: GPR40 is a well-known and promising target for diabetes. This study is the first to show the safety and effects of CPL207280, a novel GPR40/free fatty acid receptor 1 agonist, on glucose homeostasis both in vitro and in vivo in different diabetic animal models. Therefore, we propose the CPL207280 compound as a novel, glucose-lowering agent, overcoming the unmet medical needs of patients with type 2 diabetes.

A novel JAK/ROCK inhibitor, CPL409116, demonstrates potent efficacy in the mouse model of systemic lupus erythematosus.

Systemic lupus erythematosus is a chronic inflammatory disease, in which treatment is still limited due to suboptimal efficacy and toxicities associated with the available therapies. JAK kinases are well known to play an important role in systemic lupus erythematous. There is growing evidence that ROCK kinases are also important in disease development. In this paper, we present the results of the development of CPL409116, a dual JAK and ROCK inhibitor. The studies we performed demonstrate that this molecule is an effective JAK and ROCK inhibitor which efficiently blocks disease progression in NZBWF1/J mouse models of systemic lupus erythematous.

Discovery and optimization of novel pyrazole-benzimidazole CPL304110, as a potent and selective inhibitor of fibroblast growth factor receptors FGFR (1-3).

The FGFR family is characterized by four receptors (FGFR 1-4), binding to 18 ligands called fibroblast growth factors (FGFs). Aberrant activation of FGFs and their FGFRs has been implicated in a broad spectrum of human tumors. We employed the scaffolds hybridization approach, scaffold-hopping concept to synthesize a series of novel pyrazole-benzimidazole derivatives 56 (a-x). Compound 56q (CPL304110) was identified as a selective and potent pan-FGFR inhibitor for FGFR1, -2, -3 with IC50s of 0.75 nM, 0.50 nM, 3.05 nM respectively, whereas IC50 of 87.90 nM for FGFR4. Due to its favorable pharmacokinetic profile, low toxicity and potent anti-tumor activity in vivo, compound 56q is currently under evaluation in phase I clinical trial for the treatment of bladder, gastric and squamous cell lung cancers (01FGFR2018; NCT04149691).

Preclinical characterization of CPL302-253, a selective inhibitor of PI3Kδ, as the candidate for the inhalatory treatment and prevention of Asthma.

Asthma is a common chronic inflammatory disease. Although effective asthma therapies are available, part of asthmatic population do not respond to these treatment options. In this work we present the result of development of CPL302-253 molecule, a selective PI3Kδ inhibitor. This molecule is intended to be a preclinical candidate for dry powder inhalation in asthma treatment. Studies we performed showed that this molecule is safe and effective PI3Kδ inhibitor that can impact many immune functions. We developed a short, 15-day HDM induced asthma mouse model, in which we showed that CPL302-253 is able to block inflammatory processes leading to asthma development in vivo.