Triple potentiator combinations increase the functional correction of several CFTR gating mutants

Mechanistic Insights into CFTR Potentiation by the Antimicrobial Peptide Esc(1–21): Direct Interaction with the NBD1-NBD2 Interface

Cystic fibrosis (CF) is a genetic disorder caused by variants in the gene encoding the CFTR ion channel, leading to defective epithelial chloride transport, dehydrated airway mucus, chronic infections, and progressive lung damage. Although CFTR modulators have improved clinical outcomes, a subset of patients remains unresponsive to current therapies, highlighting the need for alternative strategies. The frog skin-derived antimicrobial peptide Esc(1–21) was recently identified as a CFTR potentiator, likely through direct interaction with the interface of the channel’s cytosolic nucleotide-binding domains (NBDs); yet its molecular mechanism is poorly understood. Here, we engineered a cysteine-less CFTR scaffold by introducing cysteine pairs within or outside the predicted peptide-binding region and used molecular dynamics simulation to define the putative interaction site. Disulfide cross-linking assays performed in cells expressing these constructs validated the computational predictions and showed that the peptide selectively prevents cross-link formation only when cysteines are positioned at the NBD interface, thereby supporting a direct and specific interaction with CFTR. Importantly, confocal microscopy provided evidence for peptide intracellular internalization, together with colocalization with the ion channel, indicating that Esc(1–21) can access the cytosolic side of CFTR to enhance its activity. Overall, these findings (i) provide the first mechanistic insights into the interaction of Esc(1–21) with CFTR in a cellular context; (ii) identify the NBD1-NBD2 interface as a suitable target for peptide-based potentiators; and (iii) support the development of Esc(1–21) and its derivatives as novel multifunctional therapeutic candidates for CF treatment.

A patent review of mutant-selective PI3Kα inhibitors for the treatment of different cancers (2021 - 2025).

INTRODUCTION Oncogenic PIK3CA mutations drive numerous solid tumors, rendering PI3Kα a key therapeutic target. However, conventional ATP-competitive inhibitors are severely limited by dose-limiting metabolic toxicities caused by wild-type PI3Kα inhibition. To circumvent these limitations, the drug discovery landscape is rapidly shifting toward mutant-selective allosteric inhibitors designed to spare physiological signaling and expand the therapeutic window. AREAS COVERED Utilizing the Cortellis Drug Discovery Intelligence (CDDI) database, this review evaluates patents of PI3Kα mutant-selective inhibitors disclosed between 2021 and 2025. The analysis focuses on structural features, pharmacological profiles, and medicinal chemistry strategies employed to achieve high selectivity for oncogenic mutants over the wild-type enzyme. Specifically, we examine the binding modes across two distinct allosteric domains: an H1047R-specific pocket (exemplified by Eli Lilly's inhibitors) and a pan-mutant cryptic site (engaged by RLY-2608 and STX-478). EXPERT OPINION Mutant-selective allosteric inhibitors achieve selectivity by targeting mutant residues or exploiting unique protein conformational dynamics. The rapidly diversifying patent landscape provides broader opportunities for the discovery of superior inhibitors. Furthermore, development of allosteric inhibitor based PROTACs is discussed as a promising frontier for enhancing therapeutic precision. Ultimately, deeper understanding of evolving resistance mechanisms provides the design principles required to develop next-generation PI3Kα therapeutics capable of overcoming clinical resistance.

NLRX1 is an essential, druggable regulator of mitochondrial permeability transition

Pharmacogenomics-driven precision pharmacy: Mechanisms, challenges, and translational advances

Pharmacogenomics represents a transformative paradigm in clinical pharmacology, offering the promise of individualized drug therapy based on genetic profiles. This comprehensive review examines the mechanisms underlying pharmacogenomic variability, the current state of clinical implementation, and the translational advances driving precision pharmacy practice. We systematically discuss the role of pharmacokinetic genes, including cytochrome P450 enzymes (CYP2D6, CYP2C19, CYP2C9, CYP3A4/5), thiopurine S-methyltransferase (TPMT), and solute carrier organic anion transporter family member 1B1 (SLCO1B1), as well as pharmacodynamic targets such as vitamin K epoxide reductase complex subunit 1 (VKORC1) and adrenoceptor beta 1 (ADRB1). Human leukocyte antigen (HLA) genes and their association with severe adverse drug reactions are also critically evaluated. The review further explores the evidence base supporting clinical pharmacogenomic implementation, including guidelines from the Clinical Pharmacogenetics Implementation Consortium (CPIC), the Dutch Pharmacogenetics Working Group (DPWG), and major implementation initiatives such as the IGNITE network and the PREPARE study. We examine the integration of artificial intelligence and machine learning approaches for pharmacogenomic prediction, the emergence of polygenic risk scores, and the role of multi-omics integration in refining therapeutic decision-making. Challenges, including economic barriers, regulatory considerations, health equity concerns, and healthcare system integration, are thoroughly discussed. Finally, we outline future directions for the field, emphasizing the need for global diversification of pharmacogenomic data, enhanced clinical decision support systems, and policy frameworks that facilitate equitable access to precision pharmacy services.

The Discovery of GSK3227634: A Potent Inhaled Inhibitor of the KEAP1/NRF2 Protein–Protein Interaction for the Treatment of Chronic Obstructive Pulmonary Disease

KEAP1 is the key regulator of the NRF2-mediated cytoprotective response and a target for pathologies involving oxidative stress. Compounds that covalently modify KEAP1 to activate NRF2 are clinically validated; however, their chemical reactivity may drive increased off–target activity. A more selective approach involves inhibition of the KEAP1-NRF2 protein–protein interaction as exemplified by our previous bis-aryl lead KI-696 (4). We now describe the lead optimization of the bis-aryl series that focused on increasing the population of the bioactive conformation of the free ligand to drive potency while optimizing overall physicochemical properties. This resulted in the discovery of GSK3227634 (5), an ultrahigh-affinity noncovalent inhibitor of KEAP1-NRF2 (surface plasmon resonance pKd = 10.9) and the first NRF2 activator to demonstrate target engagement and efficacy in preclinical models of oxidative stress via direct delivery to the lung. Compound 5 therefore represents a novel potential agent to treat lung diseases involving oxidative stress, such as chronic obstructive pulmonary disease.

Binding to Albumin and Off-Target Toxicity Confound the Use of LRRC8/VRAC Channel Blockers in Cell Physiology Assays

Volume-regulated anion channels (VRACs), formed by leucine-rich repeat-containing 8 (LRRC8) proteins, are ubiquitously expressed chloride channels essential for cell volume regulation and implicated in diverse physiological and pathological processes. Small-molecule VRAC inhibitors have been reported to modulate paracrine signaling, proliferation, differentiation, migration, and apoptosis, and have been patented for potential therapeutic applications in stroke, cardiovascular and metabolic diseases, and cancer. However, growing evidence indicates that many commonly used VRAC blockers exert substantial off-target effects and frequently fail to reproduce phenotypes observed after deletion of the essential VRAC subunit LRRC8A. Here, we systematically compared effects of several widely used pharmacological VRAC inhibitors with outcomes of molecular downregulation of LRRC8A in limiting proliferation of malignant glioblastoma cells derived from surgical specimens. NIH/3T3 fibroblasts served as a non-malignant control. In serum-containing media, structurally diverse VRAC blockers (DCPIB, DIDS, carbenoxolone, phloretin, and bromadiolone) reduced proliferation in a non-uniform manner, with potencies that did not correlate with reported VRAC affinities and varied markedly among cell lines. Radiotracer-based measurements of VRAC activity indicated that these discrepancies were largely attributable to binding of inhibitors to serum albumin. When experiments were repeated under serum-free conditions, all inhibitors except DIDS and phloretin induced extensive death of both malignant and non-malignant cells, confirmed by microscopy and LDH release assays. This cytotoxicity was accompanied by a marked reduction in intracellular ATP levels, consistent with previously reported mitochondrial uncoupling effects. In contrast, LRRC8A knockdown reduced proliferation without substantial cell death. Together, these findings demonstrate that most commercially available VRAC blockers limit proliferation and viability predominantly through VRAC-independent mechanisms. Under standard culture conditions, serum albumin masks much of their intrinsic cytotoxicity. These results underscore the need for rigorous molecular controls in pharmacological studies and provide basis for developing more selective and less toxic VRAC-targeting agents.