The recent advance of Interleukin-1 receptor associated kinase 4 inhibitors for the treatment of inflammation and related diseases

Construction of IRAK4 inhibitor activity prediction model based on machine learning

Interleukin-1 receptor-associated kinase 4 (IRAK4) is a crucial serine/threonine protein kinase that belongs to the IRAK family and plays a pivotal role in Toll-like receptor (TLR) and Interleukin-1 receptor (IL-1R) signaling pathways. Due to IRAK4's significant role in immunity, inflammation, and malignancies, it has become an intriguing target for discovering and developing potent small-molecule inhibitors. Consequently, there is a pressing need for rapid and accurate prediction of IRAK4 inhibitor activity. Leveraging a comprehensive dataset encompassing activity data for 1628 IRAK4 inhibitors, we constructed a prediction model using the LightGBM algorithm and molecular fingerprints. This model achieved an R2 of 0.829, an MAE of 0.317, and an RMSE of 0.460 in independent testing. To further validate the model's generalization ability, we tested it on 90 IRAK4 inhibitors collected in 2023. Subsequently, we applied the model to predict the activity of 13,268 compounds with docking scores less than - 9.503 kcal/mol. These compounds were initially screened from a pool of 1.6 million molecules in the chemdiv database through high-throughput molecular docking. Among these, 259 compounds with predicted pIC50 values greater than or equal to 8.00 were identified. We then performed ADMET predictions on these selected compounds. Finally, through a rigorous screening process, we identified 34 compounds that adhere to the four complementary drug-likeness rules, making them promising candidates for further investigation. Additionally, molecular dynamics simulations confirmed the stable binding of the screened compounds to the IRAK4 protein. Overall, this work presents a machine learning model for accurate prediction of IRAK4 inhibitor activity and offers new insights for subsequent structure-guided design of novel IRAK4 inhibitors.

Advances in Targeted Therapies for Inflammatory Diseases and Cancer: Exploring Cellular Mechanisms and Therapeutic Strategies

Managing chronic inflammatory diseases and cancers has traditionally faced challenges due to the complexity of disease mechanisms and the often-insufficient specificity of treatments. This Patent Highlight showcases findings from three innovative patents that propose distinct yet complementary therapeutic strategies to modulate key cellular processes involved in inflammation and cancer progression. The first strategy involves proteolysis targeting chimeras (PROTACs) for the selective degradation of IRAK4, a kinase central to inflammatory signaling, the second employs lipid-binding protein complexes to modulate systemic inflammatory responses, and the third utilizes selective inhibitors targeting pathogenic epithelial stem cells to prevent the progression of metaplasia into dysplasia and cancer. Collectively, these approaches highlight a shift toward precision medicine, offering the potential for synergistic applications in clinical settings.

Discovery of LC-MI-3: A Potent and Orally Bioavailable Degrader of Interleukin-1 Receptor-Associated Kinase 4 for the Treatment of Inflammatory Diseases

Interleukin-1 receptor-associated kinase 4 (IRAK4) is a promising therapeutic target in inflammation-related diseases. However, the inhibition of IRAK4 kinase activity may lead to moderate anti-inflammatory efficacy owing to the dual role of IRAK4 as an active kinase and a scaffolding protein. Herein, we report the design, synthesis, and biological evaluation of an efficient and selective IRAK4 proteolysis-targeting chimeric molecule that eliminates IRAK4 scaffolding functions. The most potent compound, LC-MI-3, effectively degraded cellular IRAK4, with a half-maximal degradation concentration of 47.3 nM. LC-MI-3 effectively inhibited the activation of downstream nuclear factor-κB signaling and exerted more potent pharmacological effects than traditional kinase inhibitors. Furthermore, LC-MI-3 exerted significant therapeutic effects in lipopolysaccharide- and Escherichia coli-induced acute and chronic inflammatory skin models compared with kinase inhibitors in vivo. Therefore, LC-MI-3 is a candidate IRAK4 degrader in alternative targeting strategies and advanced drug development.

Toll-Like Receptors and Contact Dermatitis

Contact dermatitis (CD) is a common cutaneous inflammatory condition that affects millions of people worldwide. Xenobiotic agents are frequently encountered in substances used in everyday life, making it difficult to avoid personal and occupational exposure. Toll-like receptors (TLRs) are transmembrane receptors that modulate the innate immune system in response to tissue injury or infection. TLRs play a key role in the pathophysiology of contact dermatitis. TLR signaling is involved in three major forms of CD: protein CD, allergic contact dermatitis (ACD), and irritant CD. Of the 10 TLRs found in humans, three play an important role in ACD. This makes TLRs a useful potential therapeutic target to consider against CD. In this review, we discuss the role of TLRs in CD and summarize current and emerging treatments for CD that target TLRs.

In Retrospect: Root-Cause Analysis of Structure-Activity Relationships in IRAK4 Inhibitor Zimlovisertib (PF-06650833)

In this paper, we disclose insights on the root causes of three structure-activity relationship (SAR) observations encountered in the discovery of the IRAK4 inhibitor Zimlovisertib (PF-06650833). The first is a nonlinear potency SAR encountered with the isoquinoline ether substituent, the second is a potency enhancement introduced by fluorine substitution on the lactam, and the third is a slight potency preference for all-syn (2S,3S,4S) stereochemistry in the fluorine-substituted lactam. We present new data that help to inform us of the origins of these unexpected SAR trends.

Breaking Bad Proteins-Discovery Approaches and the Road to Clinic for Degraders

Proteolysis-targeting chimeras (PROTACs) describe compounds that bind to and induce degradation of a target by simultaneously binding to a ubiquitin ligase. More generally referred to as bifunctional degraders, PROTACs have led the way in the field of targeted protein degradation (TPD), with several compounds currently undergoing clinical testing. Alongside bifunctional degraders, single-moiety compounds, or molecular glue degraders (MGDs), are increasingly being considered as a viable approach for development of therapeutics, driven by advances in rational discovery approaches. This review focuses on drug discovery with respect to bifunctional and molecular glue degraders within the ubiquitin proteasome system, including analysis of mechanistic concepts and discovery approaches, with an overview of current clinical and pre-clinical degrader status in oncology, neurodegenerative and inflammatory disease.

Discovery of IRAK4 Inhibitors (Zabedosertib) and

Interleukin-1 receptor-associated kinase 4 (IRAK4) plays a critical role in innate inflammatory processes. Here, we describe the discovery of two clinical candidate IRAK4 inhibitors, BAY1834845 (zabedosertib) and BAY1830839, starting from a high-throughput screening hit derived from Bayer's compound library. By exploiting binding site features distinct to IRAK4 using an in-house docking model, liabilities of the original hit could surprisingly be overcome to confer both candidates with a unique combination of good potency and selectivity. Favorable DMPK profiles and activity in animal inflammation models led to the selection of these two compounds for clinical development in patients.

Targeting TLR Signaling Cascades in Systemic Lupus Erythematosus and Rheumatoid Arthritis: An Update

Evidence from animal models and human genetics implicates Toll-like Receptors (TLRs) in the pathogenesis of Systemic Lupus Erythematosus (SLE) and Rheumatoid Arthritis (RA). Endosomal TLRs sensing nucleic acids were proposed to induce lupus-promoting signaling in dendritic cells, B cells, monocytes, and macrophages. Ligation of TLR4 in synovial macrophages and fibroblast-like synoviocytes (FLSs) by endogenous ligands was suggested to induce local production of mediators that amplify RA synovitis. Inhibition of TLRs using antagonists or monoclonal antibodies (mAbs) that selectively prevent extracellular or endosomal TLR ligation has emerged as an attractive treatment strategy for SLE and RA. Despite the consistent success of selective inhibition of TLR ligation in animal models, DV-1179 (dual TLR7/9 antagonist) failed to achieve pharmacodynamic effectiveness in SLE, and NI-0101 (mAb against TLR4) failed to improve arthritis in RA. Synergistic cooperation between TLRs and functional redundancy in human diseases may require pharmacologic targeting of intracellular molecules that integrate signaling downstream of multiple TLRs. Small molecules inhibiting shared kinases involved in TLR signaling and peptidomimetics disrupting the assembly of common signalosomes ("Myddosome") are under development. Targeted degraders (proteolysis-targeting chimeras (PROTACs)) of intracellular molecules involved in TLR signaling are a new class of TLR inhibitors with promising preliminary data awaiting further clinical validation.

Novel IRAK4 Inhibitors for Treating Asthma, COPD, Cancer, Autoinflammatory Diseases, and Autoimmune Diseases

Provided herein are novel IRAK4 inhibitors, pharmaceutical compositions, use of such compounds in treating asthma, COPD, cancer, autoinflammatory diseases, and autoimmune diseases, and processes for preparing such compounds.