April 30th
Discovery of Daraxonrasib (RMC-6236), a Potent and Orally Bioavailable RAS(ON) Multi-selective, Noncovalent Tri-complex Inhibitor for the Treatment of Patients with Multiple RAS-Addicted Cancers
https://pubs.acs.org/doi/abs/10.1021/acs.jmedchem.4c02314
Abstract
Oncogenic RAS mutations are among the most common in human cancers. To target the active, GTP-bound state of RAS(ON) directly, we employed an innovative tri-complex inhibitor (TCI) modality. Formation of a complex with an intracellular chaperone protein CypA, an inhibitor, and a target protein RAS blocks effector binding, inhibiting downstream RAS signaling and tumor cell proliferation. Herein, we describe the structure-guided SAR journey that led to the discovery of daraxonrasib (RMC-6236), a noncovalent, potent tri-complex inhibitor of multiple RAS mutant and wild-type (WT) variants. This orally bioavailable bRo5 macrocyclic molecule occupies a unique composite binding pocket comprising CypA and SWI/SWII regions of RAS(ON). To achieve broad-spectrum RAS isoform activity, we deployed an SAR campaign that focused on interactions with residues conserved between mutants and WT RAS isoforms. Concurrent optimization of potency and drug-like properties led to the discovery of daraxonrasib (RMC-6236), currently in clinical evaluation in RAS mutant advanced solid tumors (NCT05379985; NCT06040541; NCT06162221; NCT06445062; NCT06128551).
April 24th
Discovery of Novel, Potent, Orally Bioavailable and Efficacious, Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibitors for Hematopoietic Stem Cell Mobilization
https://pubs.acs.org/doi/abs/10.1021/acs.jmedchem.4c02889
Abstract
Hematopoietic stem cell (HSC) mobilization is often difficult to achieve in patients suffering from multiple myeloma and non-Hodgkin’s lymphoma. Granulocyte-colony stimulating factor (G-CSF) therapy alone has often not led to the desired outcomes. Herein, we describe the discovery of 7-cyclohexyl-4-hydroxy-8-oxo-N-(pyridazin-4-ylmethyl)-7,8-dihydro-2,7-naphthyridine-3-carboxamide 13, a hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitor, which was discovered by focusing on drug-like properties. Building on a previous discovery that HIF–PH inhibitors can enhance HSC mobilization in combination with G-CSF, we optimized 13 to exhibit high PHD2 potency, improved solubility, and an optimized PK profile. 13 was effective at enhancing G-CSF-induced HSC mobilization in mice at a dose of 2 mg/kg.
April 21st
Discovery of DFV890, a Potent Sulfonimidamide-Containing NLRP3 Inflammasome Inhibitor
https://pubs.acs.org/doi/abs/10.1021/acs.jmedchem.4c02759
Abstract
The discovery of DFV890 ((R)-1), a potent and selective NLRP3 antagonist, is described. Replacement of the sulfonyl urea core from the first-generation NLRP3 antagonist CRID3 with a sulfonimidamide core afforded a novel and potent series of NLRP3 antagonists. The (R)-enantiomers of the sulfonimidamide series were found to be consistently more potent than structurally related sulfonyl ureas. Replacement of the furan unit of CRID3 with a 5-substituted thiazole unit led to DFV890 ((R)-1), which potently inhibited IL-1β production in THP-1 cells and in primary human cells, blocked multiple downstream effectors of NLRP3 activation, and substantially improved PK properties and significantly lowered the predicted human dose compared to that for CRID3. DFV890 ((R)-1) was also effective in an air pouch model of gout.
April 17th
Discovery of TNG462: A Highly Potent and Selective MTA-Cooperative PRMT5 Inhibitor to Target Cancers with MTAP Deletion
https://pubs.acs.org/doi/abs/10.1021/acs.jmedchem.4c03067
Abstract
The gene encoding for MTAP is one of the most commonly deleted genes in cancer, occurring in approximately 10–15% of all human cancer. We have previously described the discovery of TNG908, a brain-penetrant clinical-stage compound that selectively targets MTAP-deleted cancer cells by binding to and inhibiting PRMT5 cooperatively with MTA, which is present in elevated concentrations in MTAP-deleted cells. Herein we describe the discovery of TNG462, a more potent and selective MTA-cooperative PRMT5 inhibitor with improved DMPK properties that is selective for MTAP-deleted cancers and is currently in Phase I/II clinical trials.
April 14th
Discovery of Elironrasib (RMC-6291), a Potent and Orally Bioavailable, RAS(ON) G12C-Selective, Covalent Tricomplex Inhibitor for the Treatment of Patients with RAS G12C-Addicted Cancers
https://pubs.acs.org/doi/abs/10.1021/acs.jmedchem.4c02313
Abstract
The discovery of elironrasib (RMC-6291) represents a significant breakthrough in targeting the previously deemed undruggable GTP-bound, active KRASG12C. To target the active state of RAS (RAS(ON)) directly, we have employed an innovative tri-complex inhibitor (TCI) modality involving formation of a complex with an inhibitor, the intracellular chaperone protein CypA, and the target protein KRASG12C in its GTP-bound form. The resulting tri-complex inhibits oncogenic signaling, inducing tumor regressions across various preclinical models of KRASG12C mutant human cancers. Here we report structure-guided medicinal chemistry efforts that led to the discovery of elironrasib, a potent, orally bioavailable, RAS(ON) G12C-selective, covalent, tri-complex inhibitor. The investigational agent elironrasib is currently undergoing phase 1 clinical trials (NCT05462717, NCT06128551, NCT06162221), with preliminary data indicating clinical activity in patients who had progressed on first-generation inactive state-selective KRASG12C inhibitors.
April 10th
Design, Synthesis, and Characterization of GluN2A Negative Allosteric Modulators Suitable for In Vivo Exploration
https://pubs.acs.org/doi/abs/10.1021/acs.jmedchem.4c02751
Abstract
N-Methyl-d-aspartate receptors are ionotropic glutamate receptors that mediate fast excitatory neurotransmission in the central nervous system. These receptors play essential roles in synaptic plasticity, learning, and memory and are implicated in various neuropathological and psychiatric disorders. Selective modulation of NMDAR subtypes, particularly GluN2A, has proven challenging. The TCN-201 derivatives MPX-004 and MPX-007 are potent and selective for GluN2A receptors, yet their physical properties limit their in vivo utility. In this study, we optimized the MPX-004/MPX-007 scaffold by modifying the linker region between the distal halogenated aromatic ring and the central pyrazine nucleus, resulting in the identification of potent and selective compounds with improved drug-like properties. Notably, compound 1 was used to develop the first GluN2A NAM-based radioligand, and compound 11 showed improved pharmacokinetics and dose-dependent receptor occupancy in vivo. Thus, we provide an array of powerful new tools for the study of GluN2A receptors.
April 7th
Discovery and Optimization of Pyrazine Carboxamide AZ3246, a Selective HPK1 Inhibitor
https://pubs.acs.org/doi/abs/10.1021/acs.jmedchem.4c02631
Abstract:
Hematopoietic progenitor kinase 1 (HPK1) is a negative regulator of the T cell receptor signaling pathway and is therefore a target of interest for immunooncology. Nonselective HPK1 inhibitors may affect other kinase components of T cell activation, blunting the beneficial impact of enhanced T cell activity that results from HPK1 inhibition itself. Here, we report the discovery of pyrazine carboxamide HPK1 inhibitors and their optimization through structure-based drug design to afford a highly selective HPK1 inhibitor, compound 24 (AZ3246). This compound induces IL-2 secretion in T cells with an EC50 of 90 nM without inhibiting antagonistic kinases, exhibits pharmacokinetic properties consistent with oral dosing, and demonstrates antitumor activity in the EMT6 syngeneic mouse model.
April 3rd
Discovery, Optimization, and Preclinical Pharmacology of EP652, a METTL3 Inhibitor with Efficacy in Liquid and Solid Tumor Models
https://pubs.acs.org/doi/abs/10.1021/acs.jmedchem.4c02225
Abstract:
METTL3 is the RNA methyltransferase predominantly responsible for the addition of N6-methyladenosine (m6A), the most abundant modification to mRNA. The prevalence of m6A and the activity and expression of METTL3 have been linked to the appearance and progression of acute myeloid leukemia (AML), thereby making METTL3 an attractive target for cancer therapeutics. We report herein the discovery and optimization of small-molecule inhibitors of METTL3, culminating in the selection of EP652 as an in vivo proof-of-concept compound. EP652 potently inhibits the enzymatic activity of METTL3, has favorable PK parameters, and demonstrates efficacy in preclinical oncology models, indicating that pharmacological inhibition of METTL3 is a viable strategy for the treatment of liquid and solid tumors.
