Discovery of LNP1892: A Precision Calcimimetic for the Treatment of Secondary Hyperparathyroidism.

The calcium sensing receptor (CaSR) plays an important role in maintaining calcium homeostasis. The use of calcimimetic cinacalcet has been established to activate CaSR and normalize hypercalcemia. However, cinacalcet has limitations due to its high cLogP and pKa. A systematic optimization of cinacalcet to reduce its cLogP and pKa yielded compound 23a (LNP1892). Compound 23a showed excellent potency and a favorable pharmacokinetics profile, and lacked the liabilities of cinacalcet, making it a highly differentiated precision calcimimetic. In adenine-diet-induced chronic kidney disease (CKD) models, 23a demonstrated robust and dose-dependent efficacy, as measured by plasma parathyroid hormone (PTH) levels. It also showed an excellent safety profile in animal studies. Phase 1 clinical trials with 23a in healthy volunteers confirmed its excellent safety, tolerability, and effectiveness in lowering PTH levels in a dose-dependent manner, without causing symptomatic hypocalcaemia. Encouraged by these promising results, LNP1892 was taken to a Phase 2 study in CKD patients.

Dual PI3Kδγ inhibition demonstrates potent anticancer effects in diffuse large B-cell lymphoma models: Discovery and preclinical characterization of LL-00084282.

Phosphoinositide 3-kinase (PI3K) pathway mediates key signaling events downstream to B-cell receptor (BCR) for survival of mature B-cells, and overexpression or overactivation of PI3Kδ is crucial for B-cell malignancies such as diffuse large B-cell lymphoma (DLBCL). Small molecule PI3Kδγ inhibitors, with a known potential to reduce activated B-cell (ABC)-DLBCL transformation, form an important class of therapeutics approved for follicular lymphoma (FL), chronic lymphocytic leukemia (CLL), small lymphocytic lymphoma (SLL). In this study, we describe discovery of a potent, selective and efficacious dual PI3Kδγ inhibitor, LL-00084282, having a differentiated efficacy profile in human ABC- and germinal center B-cell (GCB)-DLBCL cell lines. LL-00084282 displayed high potency and superior PI3Kδγ engagement with excellent selectivity over other PI3K isoforms at both IC50/90 concentrations in biochemical and cell-based assays. In contrast to selective PI3Kδ inhibitors, LL-00084282 showed superior and potent anticancer activity in both ABC- and GCB-DLBCL cell lines. LL-00084282 demonstrated in-vivo efficacy in OCI-Ly10 and SU-DHL-6 xenografts with good tolerability. Furthermore, LL-00084282 inhibited pro-inflammatory cytokine secretion and reduced basophil activation in human PBMCs, showing potential implications in immunoinflammatory conditions. Good pharmacokinetic properties in higher species and desirable efficacy profile highlights potential of this novel PI3Kδγ inhibitor for further clinical evaluation in DLBCL patients.

Discovery of Novel, Potent, Brain-Permeable, and Orally Efficacious Positive Allosteric Modulator of α7 Nicotinic Acetylcholine Receptor [4-(5-(4-Chlorophenyl)-4-methyl-2-propionylthiophen-3-yl)benzenesulfonamide]: Structure-Activity Relationship and Preclinical Characterization.

The discovery of a series of thiophenephenylsulfonamides as positive allosteric modulators (PAM) of α7 nicotinic acetylcholine receptor (α7 nAChR) is described. Optimization of this series led to identification of compound 28, a novel PAM of α7 nicotinic acetylcholine receptor (α7 nAChR). Compound 28 showed good in vitro potency, with pharmacokinetic profile across species with excellent brain penetration and residence time. Compound 28 robustly reversed the cognitive deficits in episodic/working memory in both time-delay and scopolamine-induced amnesia paradigms in the novel object and social recognition tasks, at very low dose levels. Additionally, compound 28 has shown excellent safety profile in phase 1 clinical trials and is being evaluated for efficacy and safety as monotherapy in patients with mild to moderate Alzheimer's disease.

Discovery and Characterization of Potent Pan-Genotypic HCV NS5A Inhibitors Containing Novel Tricyclic Central Core Leading to Clinical Candidate.

The identification of a novel class of potent pan-genotypic NS5A inhibitors with good pharmacokinetic profile suitable for potential use in treating HCV infections is disclosed here. The present series of compounds are with less complex tricyclic central core, identified through a systematic SAR study carried out on biphenyl moiety. The SAR outcome has confirmed the requirement of near planar and linear conformation of the molecule to achieve the best pan-genotypic activity. In addition, SAR with substituted imidazoles on improvement of antiviral activity is disclosed. The newly identified compounds 12, 16, 19-21 have shown desirable pharmacokinetic profiles with a favorable uptake of compounds in liver and maintained a significant concentration for up to 8 h in the liver. In addition, compounds 20 and 21 have shown superior pan-genotypic anti-HCV activity compared to ledipasvir and daclatasvir. Additional characterization and preliminary safety assessment resulted in the identification of compound 20 as a potential clinical candidate.