3-[2-(Aminomethyl)-5-[(pyridin-4-yl)carbamoyl]phenyl] benzoates as soft ROCK inhibitors

Discovery of a novel ROCK2 ATP competitive inhibitor by DNA-encoded library selection

Neurodegeneration disorders, such as Alzheimer's disease (AD), have garnered significant attention due to their impact on individuals and society as a whole. Understanding the mechanisms behind these disorders and developing effective therapy strategies is of utmost importance. One potential therapeutic target that has emerged is Rho-associated coiled-coil containing protein kinase 2 (ROCK2), as its accumulation and activity have been closely linked to memory loss. In this report, we present the findings of a recent discovery involving a new molecule that has the ability to competitively inhibit ROCK2 activity. This molecule was identified through the utilization of a DNA-encoded library (DEL) screening platform. Following selection against ROCK2, an off-DNA compound was synthesized and examined to ascertain its inhibitory properties, selectivity, mechanism of action, and binding mode analysis. From the screening, compound CH-2 has demonstrated an IC50 value of 28 nM against ROCK2, while exhibiting a 5-fold selectivity over ROCK1. Further analysis through molecular docking has provided insights into the specific binding modes of this compound. Our findings suggest that DEL selection offers a rapid method for identifying new inhibitors. Among these, the CH-2 compound shows promise as a potential ROCK2 inhibitor and warrants further investigation.

Application and Study of ROCK Inhibitors in Pulmonary Fibrosis: Recent Developments and Future Perspectives

Rho-associated coiled-coil-containing kinases (ROCKs), serine/threonine protein kinases, were initially identified as downstream targets of the small GTP-binding protein Rho. Pulmonary fibrosis (PF) is a lethal disease with limited therapeutic options and a particularly poor prognosis. Interestingly, ROCK activation has been demonstrated in PF patients and in animal PF models, making it a promising target for PF treatment. Many ROCK inhibitors have been discovered, and four of these have been approved for clinical use; however, no ROCK inhibitors are approved for the treatment of PF patients. In this article, we describe ROCK signaling pathways and the structure-activity relationship, potency, selectivity, binding modes, pharmacokinetics (PKs), biological functions, and recently reported inhibitors of ROCKs in the context of PF. We will also focus our attention on the challenges to be addressed when targeting ROCKs and discuss the strategy of ROCK inhibitor use in the treatment of PF.

Sovesudil (locally acting rho kinase inhibitor) for the treatment of normal-tension glaucoma: the randomized phase II study

PURPOSE

To evaluate ocular hypotensive efficacy and the safety of sovesudil (formally known as PHP-201), a novel Rho-associated protein kinase (ROCK) inhibitor, in patients with normal-tension glaucoma (NTG).

DESIGN

Multicentre, prospective, double-masked, randomized, placebo-controlled, parallel clinical study.

METHODS

Patients with NTG (unmedicated baseline IOP ≤ 21 mmHg) were randomized in 3 groups and treated with sovesudil in concentrations of 0.25% and 0.5%, or with a placebo three times daily (TID) for 4 weeks. The primary end-point was the mean diurnal IOP change from the baseline at week 4. Safety was recorded over a 4-week treatment period and the following 2-week observation period.

RESULTS

A total of 119 patients were included in the primary efficacy analysis. The mean diurnal IOP change from the baseline at week 4 was -1.56 mmHg for the high-dose group, -1.10 mmHg for the low-dose group and -0.65 mmHg for the placebo group. The difference between the high-dose and the placebo groups was -0.91 mmHg (95% confidence intervals: -1.73, -0.09). 0.5% sovesudil TID met the criteria for superiority to the placebo. The most frequent ocular adverse event among sovesudil-treated patients was conjunctival hyperaemia (24.4% for the high-dose and 17.5% for the low-dose group) and predominately classified as mild.

CONCLUSIONS

Sovesudil 0.25% and 0.5% TID showed statistically significant IOP-lowering effects and 0.5% concentration's IOP-lowering effects met the superiority criteria in comparison with the placebo at week 4. Sovesudil was well tolerated with mild adverse events including relatively low incidence of conjunctival hyperaemia in patients with NTG.

Drugs for the treatment of glaucoma: Targets, structure-activity relationships and clinical research

Glaucoma is the third leading cause of blindness and impairment of vision worldwide, after refractive errors and cataracts. According to the survey, the number of people with glaucoma is more than 76 million, with projections increasing to 112 million by 2040. With the coming of an aging society, the number of people suffering from glaucoma will increase day by day. Glaucoma is a heterogeneous disease characterized by damage to the head of the optic nerve and visual field. High intraocular pressure is a major risk and cause of glaucoma optic neuropathy. Therefore, drug lowering intraocular pressure therapy is still the first-line therapy in clinical practice. Here, the targets, structure-activity relationship, and clinical progress of drugs for the treatment of glaucoma are reviewed.

Investigational Rho Kinase Inhibitors for the Treatment of Glaucoma

This review provides a comprehensive update on emerging ROCK inhibitors as an innovative treatment option for lowering intraocular pressure (IOP) in glaucoma and aims to describe the structure, mechanism of action, pharmaceutical characteristics, desirable ocular effects, including side effects for each agent. A literature review was conducted using PubMed, Scopus, clinicaltrials.gov, ARVO journals, Cochrane library and Selleckchem. Databases were searched using "investigational Rho kinase inhibitors," and "glaucoma" as keywords. In addition to this building block strategy, successive fractions were employed to further refine the results. Of the several ROCK inhibitors discovered, only two drugs are currently approved for glaucoma treatment; Netarsudil in the USA and Ripasudil in Japan and China. We identified and reviewed 15 agents currently in laboratory or clinical trials. These agents lower IOP mainly by decreasing outflow resistance through pharmacologic relaxation of the trabecular meshwork (TM) cells and reducing episcleral venous pressure. They have an optimistic safety profile; however, conjunctival hyperemia, conjunctival hemorrhage, pain on instillation, and corneal verticillata are common. Other properties such as neuroprotection (enhancing optic nerve blood flow and promoting axonal regeneration), anti-fibrotic activity, and endothelial cell proliferation may improve the visual prognosis and surgical outcomes in glaucoma. In addition, these agents have the potential to work synergistically with other topical glaucoma medications.

Design of novel ROCK inhibitors using fragment-based de novo drug design approach

Rho-associated coiled-coil protein kinase (ROCK) is playing a vital role in the regulation of key cellular events and also responsible for causing several pathological conditions such as cancer, hypertension, Alzheimer's, cerebral vasospasm, and cardiac stroke. Therefore, it has attracted us to target ROCK protein as a potential therapeutic target for combating various diseases. Consequently, we investigated the active site of ROCK I protein and designed novel leads against the target using the de novo evolution drug design approach. Caffeic acid (an aglycone of acteoside) as a scaffold and fragments from 336 reported ROCK inhibitors were used for the design of novel leads. Multiple copy simultaneous search docking was used to identify the suitable fragments to be linked with the scaffold. Basic medicinal chemistry rules, coupled with structural insights generated by docking, led to the design of 7a, 8a, 9a, and 10a as potential ROCK I inhibitors. The designed leads showed better binding than the approved drug fasudil and also interacted with the key hinge region residue Met156 of ROCK I. Further, molecular dynamics (MD) simulation revealed that the protein-ligand complexes were stable and maintained the hydrogen bond with Met156 throughout the MD run. The promising in silico outcomes suggest that the designed compounds could be suitable anti-cancer leads that need to be synthesized and tested in various cancer cell lines. Graphical abstract.

Ocular Disease Therapeutics: Design and Delivery of Drugs for Diseases of the Eye

The ocular drug discovery field has evidenced significant advancement in the past decade. The FDA approvals of Rhopressa, Vyzulta, and Roclatan for glaucoma, Brolucizumab for wet age-related macular degeneration (wet AMD), Luxturna for retinitis pigmentosa, Dextenza (0.4 mg dexamethasone intracanalicular insert) for ocular inflammation, ReSure sealant to seal corneal incisions, and Lifitegrast for dry eye represent some of the major developments in the field of ocular therapeutics. A literature survey also indicates that gene therapy, stem cell therapy, and target discovery through genomic research represent significant promise as potential strategies to achieve tissue repair or regeneration and to attain therapeutic benefits in ocular diseases. Overall, the emergence of new technologies coupled with first-in-class entries in ophthalmology are highly anticipated to restructure and boost the future trends in the field of ophthalmic drug discovery. This perspective focuses on various aspects of ocular drug discovery and the recent advances therein. Recent medicinal chemistry campaigns along with a brief overview of the structure-activity relationships of the diverse chemical classes and developments in ocular drug delivery (ODD) are presented.

Targeting extracellular matrix stiffness to attenuate disease: From molecular mechanisms to clinical trials

Tissues stiffen during aging and during the pathological progression of cancer, fibrosis, and cardiovascular disease. Extracellular matrix stiffness is emerging as a prominent mechanical cue that precedes disease and drives its progression by altering cellular behaviors. Targeting extracellular matrix mechanics, by preventing or reversing tissue stiffening or interrupting the cellular response, is a therapeutic approach with clinical potential. Major drivers of changes to the mechanical properties of the extracellular matrix include phenotypically converted myofibroblasts, transforming growth factor β (TGFβ), and matrix cross-linking. Potential pharmacological interventions to overcome extracellular matrix stiffening are emerging clinically. Aside from targeting stiffening directly, alternative approaches to mitigate the effects of increased matrix stiffness aim to identify and inhibit the downstream cellular response to matrix stiffness. Therapeutic interventions that target tissue stiffening are discussed in the context of their limitations, preclinical drug development efforts, and clinical trials.

Glaucoma: Biological Trabecular and Neuroretinal Pathology with Perspectives of Therapy Innovation and Preventive Diagnosis

Glaucoma is a common degenerative disease affecting retinal ganglion cells (RGC) and optic nerve axons, with progressive and chronic course. It is one of the most important reasons of social blindness in industrialized countries. Glaucoma can lead to the development of irreversible visual field loss, if not treated. Diagnosis may be difficult due to lack of symptoms in early stages of disease. In many cases, when patients arrive at clinical evaluation, a severe neuronal damage may have already occurred. In recent years, newer perspective in glaucoma treatment have emerged. The current research is focusing on finding newer drugs and associations or better delivery systems in order to improve the pharmacological treatment and patient compliance. Moreover, the application of various stem cell types with restorative and neuroprotective intent may be found appealing (intravitreal autologous cellular therapy). Advances are made also in terms of parasurgical treatment, characterized by various laser types and techniques. Moreover, recent research has led to the development of central and peripheral retinal rehabilitation (featuring residing cells reactivation and replacement of defective elements), as well as innovations in diagnosis through more specific and refined methods and inexpensive tests.

AMA0428, A Potent Rock Inhibitor, Attenuates Early and Late Experimental Diabetic Retinopathy

PURPOSE

Diabetic retinopathy (DR) is characterized by an early stage of inflammation and vessel leakage, and an advanced vasoproliferative stage. Also, neurodegeneration might play an important role in disease pathogenesis. The aim of this study was to investigate the effect of the Rho kinase (ROCK) inhibitor, AMA0428, on these processes.

METHODS

The response to ROCK inhibition by AMA0428 (1 µg) was studied in vivo using the murine model for streptozotocin (STZ)-induced diabetes, focusing on early non-proliferative DR features and the oxygen-induced retinopathy (OIR) model to investigate proliferative DR. Intravitreal (IVT) administration of AMA0428 was compared with murine anti-VEGF-R2 antibody (DC101, 6.2 µg) and placebo (H₂O/PEG; 1C8). Outcome was assessed by analyzing leukostasis using fluorescein isothiocyanate coupled concanavalin A (FITC-ConA) and vessel leakage (bovine serum albumin conjugated with fluorescein isothiocyanate; FITC-BSA)/neovascularization and neurodegeneration by immunohistological approaches (hematoxylin and eosin (H&E), terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling (TUNEL), Brn3a). ELISA and Western blotting were employed to unravel the consequences of ROCK inhibition (1 µM AMA0428) on myosin phosphatase target protein (MYPT)-1 phosphorylation, endothelial nitric oxide synthase (eNOS) phosphorylation, and vascular endothelial growth factor (VEGF) levels in retinas of diabetic mice, on NF-κβ activity and ICAM-1 expression in endothelial cells (ECs).

RESULTS

In vivo, AMA0428 significantly reduced vessel leakage and neovascularization, respectively, in the STZ and OIR model, comparable to DC101 therapy. Additionally, the ROCK inhibitor decreased neurodegeneration in both models and inhibited leukostasis by 30% (p < 0.05) in the STZ model (p < 0.05), while DC101 had no positive effect on the outcome of these latter processes. ROCK activity was upregulated in the diabetic retina and AMA0428 administration resulted in decreased phospho-MYPT-1, enhanced phospho-eNOS, and reduced VEGF levels. In vitro, AMA0428 interfered with NF-κβ activity, thereby inhibiting ICAM-1 expression in ECs.

CONCLUSIONS

Targeting ROCK with AMA0428 effectively attenuated outcome in an early DR model (STZ) and a late vasoproliferative retinopathy model (OIR). These findings make AMA0428 a promising candidate with an additional anti-inflammatory and neuroprotective benefit for DR patients, as compared with anti-VEGF treatment.

Discovery of Molecular Therapeutics for Glaucoma: Challenges, Successes, and Promising Directions

Glaucoma, a heterogeneous ocular disorder affecting ∼60 million people worldwide, is characterized by painless neurodegeneration of retinal ganglion cells (RGCs), resulting in irreversible vision loss. Available therapies, which decrease the common causal risk factor of elevated intraocular pressure, delay, but cannot prevent, RGC death and blindness. Notably, it is changes in the anterior segment of the eye, particularly in the drainage of aqueous humor fluid, which are believed to bring about changes in pressure. Thus, it is primarily this region whose properties are manipulated in current and emerging therapies for glaucoma. Here, we focus on the challenges associated with developing treatments, review the available experimental methods to evaluate the therapeutic potential of new drugs, describe the development and evaluation of emerging Rho-kinase inhibitors and adenosine receptor ligands that offer the potential to improve aqueous humor outflow and protect RGCs simultaneously, and present new targets and approaches on the horizon.

Tetrahydro-pyrimido-indoles as selective LIMK inhibitors: synthesis, selectivity profiling and structure–activity studies

Extensive structure–activity studies on three different modification sites resulted in a series of LIM kinase inhibitors, containing a novel tricyclic hinge-binding motif based on the pyrrolopyrimidine scaffold.

Kinase profiling in early stage drug discovery: sorting things out

Protein kinases represent one of the largest superfamilies of drugable targets and a major research area for both the pharmaceutical industry and academic groups. This has resulted in the emergence of numerous screening technologies and services dedicated to kinase profiling. In spite of this plentiful offering, the field is not without its own pitfalls, as the profusion of reported conditions and data can ultimately complicate interpretation of project results. Here, we discuss how kinase profiling was used in our early stage drug discovery efforts, from the perspective of a smaller biotech relying largely on assay outsourcing.

Rho Kinase (ROCK) Inhibitors and Their Therapeutic Potential

Rho kinases (ROCKs) belong to the serine-threonine family, the inhibition of which affects the function of many downstream substrates. As such, ROCK inhibitors have potential therapeutic applicability in a wide variety of pathological conditions including asthma, cancer, erectile dysfunction, glaucoma, insulin resistance, kidney failure, neuronal degeneration, and osteoporosis. To date, two ROCK inhibitors have been approved for clinical use in Japan (fasudil and ripasudil) and one in China (fasudil). In 1995 fasudil was approved for the treatment of cerebral vasospasm, and more recently, ripasudil was approved for the treatment of glaucoma in 2014. In this Perspective, we present a comprehensive review of the physiological and biological functions for ROCK, the properties and development of over 170 ROCK inhibitors as well as their therapeutic potential, the current status, and future considerations.

Towards axonal regeneration and neuroprotection in glaucoma: Rho kinase inhibitors as promising therapeutics

Due to a prolonged life expectancy worldwide, the incidence of age-related neurodegenerative disorders such as glaucoma is increasing. Glaucoma is the second cause of blindness, resulting from a slow and progressive loss of retinal ganglion cells (RGCs) and their axons. Up to now, intraocular pressure (IOP) reduction is the only treatment modality by which ophthalmologists attempt to control disease progression. However, not all patients benefit from this therapy, and the pathophysiology of glaucoma is not always associated with an elevated IOP. These limitations, together with the multifactorial etiology of glaucoma, urge the pressing medical need for novel and alternative treatment strategies. Such new therapies should focus on preventing or retarding RGC death, but also on repair of injured axons, to ultimately preserve or improve structural and functional connectivity. In this respect, Rho-associated coiled-coil forming protein kinase (ROCK) inhibitors hold a promising potential to become very prominent drugs for future glaucoma treatment. Their field of action in the eye does not seem to be restricted to IOP reduction by targeting the trabecular meshwork or improving filtration surgery outcome. Indeed, over the past years, important progress has been made in elucidating their ability to improve ocular blood flow, to prevent RGC death/increase RGC survival and to retard axonal degeneration or induce proper axonal regeneration. Within this review, we aim to highlight the currently known capacity of ROCK inhibition to promote neuroprotection and regeneration in several in vitro, ex vivo and in vivo experimental glaucoma models.

Novel Roflumilast analogs as soft PDE4 inhibitors

PDE4 inhibitors are of high interest for treatment of a wide range of inflammatory or autoimmune diseases. Their potential however has not yet been realized due to target-associated side effects, resulting in a low therapeutic window. We herein report the design, synthesis and evaluation of novel PDE4 inhibitors containing a γ-lactone structure. Such molecules are designed to undergo metabolic inactivation when entering circulation, thereby limiting systemic exposure and reducing the risk for side effects. The resulting inhibitors were highly active on both PDE4B1 and PDE4D2 and underwent rapid degradation in human plasma by paraoxonase 1. In contrast, their metabolites displayed markedly reduced permeability and/or on-target activity.

Rho kinase inhibitors: a patent review (2012 - 2013)

INTRODUCTION

The Rho kinase/ROCK is critical in vital signal transduction pathways central to many essential cellular activities. Since ROCK possess multiple substrates, modulation of ROCK activity is useful for treatment of many diseases.

AREAS COVERED

Significant progress has been made in the development of ROCK inhibitors over the past two years (Jan 2012 to Aug 2013). Patent search in this review was based on FPO IP Research and Communities and Espacenet Patent Search. In this review, patent applications will be classified into four groups for discussions. The grouping is mainly based on structures or scaffolds (groups 1 and 2) and biological functions of ROCK inhibitors (groups 3 and 4). These four groups are i) ROCK inhibitors based on classical structural elements for ROCK inhibition; ii) ROCK inhibitors based on new scaffolds; iii) bis-functional ROCK inhibitors; and iv) novel applications of ROCK inhibitors.

EXPERT OPINION

Although currently only one ROCK inhibitor (fasudil) is used as a drug, more drugs based on ROCK inhibition are expected to be advanced into market in the near future. Several directions should be considered for future development of ROCK inhibitors, such as soft ROCK inhibitors, bis-functional ROCK inhibitors, ROCK2 isoform-selective inhibitors, and ROCK inhibitors as antiproliferation agents.