CHF6001 I: a novel highly potent and selective phosphodiesterase 4 inhibitor with robust anti-inflammatory activity and suitable for topical pulmonary administration.

This study examined the pharmacologic characterization of CHF6001 [(S)-3,5-dichloro-4-(2-(3-(cyclopropylmethoxy)-4-(difluoromethoxy)phenyl)-2-(3-(cyclopropylmethoxy)-4-(methylsulfonamido)benzoyloxy)ethyl)pyridine 1-oxide], a novel phosphodiesterase (PDE)4 inhibitor designed for treating pulmonary inflammatory diseases via inhaled administration. CHF6001 was 7- and 923-fold more potent than roflumilast and cilomilast, respectively, in inhibiting PDE4 enzymatic activity (IC50 = 0.026 ± 0.006 nM). CHF6001 inhibited PDE4 isoforms A-D with equal potency, showed an elevated ratio of high-affinity rolipram binding site versus low-affinity rolipram binding site (i.e., >40) and displayed >20,000-fold selectivity versus PDE4 compared with a panel of PDEs. CHF6001 effectively inhibited (subnanomolar IC50 values) the release of tumor necrosis factor-α from human peripheral blood mononuclear cells, human acute monocytic leukemia cell line macrophages (THP-1), and rodent macrophages (RAW264.7 and NR8383). Moreover, CHF6001 potently inhibited the activation of oxidative burst in neutrophils and eosinophils, neutrophil chemotaxis, and the release of interferon-γ from CD4(+) T cells. In all these functional assays, CHF6001 was more potent than previously described PDE4 inhibitors, including roflumilast, UK-500,001 [2-(3,4-difluorophenoxy)-5-fluoro-N-((1S,4S)-4-(2-hydroxy-5-methylbenzamido)cyclohexyl)nicotinamide], and cilomilast, and it was comparable to GSK256066 [6-((3-(dimethylcarbamoyl)phenyl)sulfonyl)-4-((3-methoxyphenyl)amino)-8-methylquinoline-3-carboxamide]. When administered intratracheally to rats as a micronized dry powder, CHF6001 inhibited liposaccharide-induced pulmonary neutrophilia (ED50 = 0.205 µmol/kg) and leukocyte infiltration (ED50 = 0.188 µmol/kg) with an efficacy comparable to a high dose of budesonide (1 µmol/kg i.p.). In sum, CHF6001 has the potential to be an effective topical treatment of conditions associated with pulmonary inflammation, including asthma and chronic obstructive pulmonary disease.

Discovery of a Potent, Selective, and Orally Bioavailable Tool Compound for Probing the Role of Lysophosphatidic Acid Type 2 Receptor Antagonists in Fibrotic Disorders.

Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal disease characterized by lung fibrosis leading to an irreversible decline of lung function. Current antifibrotic drugs on the market slow down but do not prevent the progression of the disease and are associated with tolerability issues. The involvement of lysophosphatidic acid receptor 2 (LPA2) in IPF is supported by LPA2 knockdown studies. To further validate the role of LPA2 receptors in modulating IPF and potentially other fibrotic processes, a potent and selective LPA2 receptor antagonist with a good pharmacokinetic (PK) profile is needed. Herein, we report the medicinal chemistry exploration that led to the discovery of a new class of highly potent and selective LPA2 antagonists. Among them, compound 58 exhibits excellent potency, selectivity, and oral PK profile, making it a suitable tool for probing the involvement of LPA2 receptors in IPF and other fibrotic processes.

Optimization of M3 Antagonist-PDE4 Inhibitor (MAPI) Dual Pharmacology Molecules for the Treatment of COPD.

Aiming at the inhaled treatment of pulmonary diseases, the optimization process of the previously reported MAPI compound 92a is herein described. The project was focused on overcoming the chemical stability issue and achieving a balanced bronchodilator/anti-inflammatory profile in rats in order to be confident in a clinical effect without having to overdose at one of the biological targets. The chemical strategy was based on fine-tuning of the substitution pattern in the muscarinic and PDE4 structural portions of the dual pharmacology compounds, also making use of the analysis of a proprietary crystal structure in the PDE4 catalytic site. Compound 10f was identified as a chemically stable, potent, and in vivo balanced MAPI lead compound, as assessed in bronchoconstriction and inflammation assays in rats after intratracheal administration. After the in-depth investigation of the pharmacological and solid-state profile, 10f proved to be safe and suitable for development.

Design, Synthesis, and Biological Characterization of Inhaled p38α/ß MAPK Inhibitors for the Treatment of Lung Inflammatory Diseases.

The identification of novel inhaled p38α/ß mitogen-activated protein kinases (MAPK) (MAPK14/11) inhibitors suitable for the treatment of pulmonary inflammatory conditions has been described. A rational drug design approach started from the identification of a novel tetrahydronaphthalene series, characterized by nanomolar inhibition of p38α with selectivity over p38γ and p38δ isoforms. SAR optimization of 1c is outlined, where improvements in potency against p38α and ligand-enzyme dissociation kinetics led to several compounds showing pronounced anti-inflammatory effects in vitro (inhibition of TNFα release). Targeting of the defined physicochemical properties allowed the identification of compounds 3h, 4e, and 4f, which showed, upon intratracheal instillation, low plasma levels, prolonged lung retention, and anti-inflammatory effects in a rat acute model of a bacterial endotoxin-induced pulmonary inflammation. Compound 4e, in particular, displayed remarkable efficacy and duration of action and was selected for progression in disease models of asthma and chronic obstructive pulmonary disease (COPD).

Effectiveness of an empowerment-based intervention for psoriasis among patients attending a medical spa.

There is increasing interest in the management of chronic diseases through patient self-efficacy procedures. Very few studies are available assessing the efficacy of empowerment-based educational interventions for psoriasis patients. To evaluate an educational programme for increasing empowerment, in a spa setting (Comano, Italy). An educational intervention with pre-post test for empowerment evaluation was employed with patients assigned either to a control (balneotherapy) or an experimental group (balneotherapy plus empowerment-based educational interventions) (quasi-experimental). The outcome measures were self-reported scores through validated tools for empowerment, severity of disease and quality of life, assessed before and after a single two-hour empowerment-based educational intervention. A total of 136 patients completed the study (control n. 49; experimental n. 87). The experimental group reported higher levels of empowerment with improved knowledge about the disease as compared to the control group. After the balneotherapy, both groups reported a positive effect on quality of life. Patients' characteristics linked to intervention effectiveness were identified. A single empowerment-based educational intervention has the potential to increase psoriasis patients' empowerment by means of increased knowledge. It is advisable to promote it as a standardized, low-cost practice for motivated patients.

Discovery of M3 Antagonist-PDE4 Inhibitor Dual Pharmacology Molecules for the Treatment of Chronic Obstructive Pulmonary Disease.

In this paper, we report the discovery of dual M3 antagonist-PDE4 inhibitor (MAPI) compounds for the inhaled treatment of pulmonary diseases. The identification of dual compounds was enabled by the intuition that the fusion of a PDE4 scaffold derived from our CHF-6001 series with a muscarinic scaffold through a common linking ring could generate compounds active versus both the transmembrane M3 receptor and the intracellular PDE4 enzyme. Two chemical series characterized by two different muscarinic scaffolds were investigated. SAR optimization was aimed at obtaining M3 nanomolar affinity coupled with nanomolar PDE4 inhibition, which translated into anti-bronchospastic efficacy ex vivo (inhibition of rat trachea contraction) and into anti-inflammatory efficacy in vitro (inhibition of TNFα release). Among the best compounds, compound 92a achieved the goal of demonstrating in vivo efficacy and duration of action in both the bronchoconstriction and inflammation assays in rat after intratracheal administration.

Functionalized pyrazoles and pyrazolo[3,4-d]pyridazinones: Synthesis and evaluation of their phosphodiesterase 4 inhibitory activity.

A series of pyrazoles and pyrazolo[3,4-d]pyridazinones were synthesized and evaluated for their PDE4 inhibitory activity. All the pyrazoles were found devoid of activity, whereas some of the novel pyrazolo[3,4-d]pyridazinones showed good activity as PDE4 inhibitors. The most potent compounds in this series showed an IC(50) in the nanomolar range. The ability to inhibit TNF-alpha release in human PBMCs was determined for two representative compounds, finding values in the sub-micromolar range. SARs studies demonstrated that the best arranged groups around the heterocyclic core are 2-chloro-, 2-methyl- and 3-nitrophenyl at position 2, an ethyl ester at position 4 and a small alkyl group at position 6. Molecular modeling studies performed on a representative compound allowed to define its binding mode to the PDE4B isoform.

Discovery of diaryl imidazolidin-2-one derivatives, a novel class of muscarinic M3 selective antagonists (Part 1).

Pharmacophore-based structural identification, synthesis, and structure-activity relationships of a new class of muscarinic M3 receptor antagonists, the diaryl imidazolidin-2-one derivatives, are described. The versatility of the discovered scaffold allowed for several structural modifications that resulted in the discovery of two distinct classes of compounds, specifically a class of tertiary amine derivatives (potentially useful for the treatment of overactive bladder by oral administration) and a class of quaternary ammonium salt derivatives (potentially useful for the treatment of respiratory diseases by the inhalation route of administration). In this paper, we describe the synthesis and biological activity of tertiary amine derivatives. For these compounds, selectivity for the M3 receptor toward the M2 receptor was crucial, because the M2 receptor subtype is mainly responsible for adverse systemic side effects of currently marketed muscarinic antagonists. Compound 50 showed the highest selectivity versus M2 receptor, with binding affinity for M3 receptor Ki = 4.8 nM and for M2 receptor Ki = 1141 nM. Functional in vitro studies on selected compounds confirmed the antagonist activity toward the M3 receptor and functional selectivity toward the M2 receptor.

Discovery of diaryl imidazolidin-2-one derivatives, a novel class of muscarinic M3 selective antagonists (Part 2).

Synthesis and biological activity of a novel class of quaternary ammonium salt muscarinic M3 receptor antagonists, showing high selectivity versus the M2 receptor, are described. Selected compounds exhibited potent anticholinergic properties, in isolated guinea-pig trachea, and good functional selectivity for trachea over atria. In vivo, the same compounds potently inhibited acetylcholine-induced bronchoconstriction after intratracheal administration in the guinea pig.

Discovery and Optimization of Thiazolidinyl and Pyrrolidinyl Derivatives as Inhaled PDE4 Inhibitors for Respiratory Diseases.

Phosphodiesterase 4 (PDE4) is a key cAMP-metabolizing enzyme involved in the pathogenesis of inflammatory disease, and its pharmacological inhibition has been shown to exert therapeutic efficacy in chronic obstructive pulmonary disease (COPD). Herein, we describe a drug discovery program aiming at the identification of novel classes of potent PDE4 inhibitors suitable for pulmonary administration. Starting from a previous series of benzoic acid esters, we explored the chemical space in the solvent-exposed region of the enzyme catalytic binding pocket. Extensive structural modifications led to the discovery of a number of heterocycloalkyl esters as potent in vitro PDE4 inhibitors. (S*,S**)-18e and (S*,S**)-22e, in particular, exhibited optimal in vitro ADME and pharmacokinetics properties and dose-dependently counteracted acute lung eosinophilia in an experimental animal model. The optimal biological profile as well as the excellent solid-state properties suggest that both compounds have the potential to be effective topical agents for treating respiratory inflammatory diseases.

Novel class of benzoic acid ester derivatives as potent PDE4 inhibitors for inhaled administration in the treatment of respiratory diseases.

The first steps in the selection process of a new anti-inflammatory drug for the inhaled treatment of asthma and chronic obstructive pulmonary disease are herein described. A series of novel ester derivatives of 1-(3-(cyclopropylmethoxy)-4-(difluoromethoxy)phenyl)-2-(3,5-dichloropyridin-4-yl) ethanol have been synthesized and evaluated for inhibitory activity toward cAMP-specific phosphodiesterase-4 (PDE4). In particular, esters of variously substituted benzoic acids were extensively explored, and structural modification of the alcoholic and benzoic moieties were performed to maximize the inhibitory potency. Several compounds with high activity in cell-free and cell-based assays were obtained. Through the evaluation of opportune in vitro ADME properties, a potential candidate suitable for inhaled administration in respiratory diseases was identified and tested in an in vivo model of pulmonary inflammation, proving its efficacy.

Effects of 3-phenyl-4-[[4-[2-(1-piperidinyl)ethoxy]phenyl]methyl]- 2H-1-benzopyran-7-ol (CHF 4056), a novel nonsteroidal estrogen agonist/antagonist, on reproductive and nonreproductive tissue.

We have discovered a new, nonsteroidal, estrogen agonist/antagonist, 3-phenyl-4-[[4-[2-(1-piperidinyl)ethoxy]phenyl] methyl]-2H-1-benzopyran-7-ol (CHF 4056). The aim of this study was to determine the effects of CHF 4056 on a series of parameters (body weight, uteri, serum cholesterol, and bones) that were previously shown to be sensitive to estrogens and to selective estrogen receptor modulators (SERMs). CHF 4056 is a benzopyran derivative that binds with high affinity to the human estrogen receptors alpha and beta (dissociation constant K(i) of 0.041 and 0.157 nM, respectively). In immature rats, CHF 4056 induced a full estrogen antagonism (half-maximal efficacious dose = 0.33 mg/kg x day p.o.) coupled with a lack of uterine stimulatory activity, whereas the structurally related SERM levormeloxifene demonstrated a maximal partial agonist effect of approximately 65% that of 17alpha-ethynyl estradiol (EE2). In ovariectomized (OVX) rats, CHF 4056 (0.1-1 mg/kg x day p.o. for 4 weeks) significantly reduced OVX-induced bone loss in the lumbar spine L1-4 and OVX-induced increase in serum osteocalcin. These protective effects on bone tissue were comparable with those of 0.1 mg/kg x day EE2. In the same experimental conditions, serum cholesterol was significantly lower in the CHF 4056-treated animals, compared with vehicle-treated OVX rats. In line with the results observed in immature rats, also in OVX rats CHF 4056 diverged dramatically from EE2 and levormeloxifene in its lack of significant estrogenic effects on uterine tissue. In conclusion, CHF 4056 is a new SERM that produces beneficial effects on bone and cholesterol levels, while maintaining antagonist effects on the uterus.

Pharmacological actions of a novel, potent, tissue-selective benzopyran estrogen.

We have identified a new benzopyran derivative, 3-(4-methoxy) phenyl-4-[[4-[2-(1-piperidinyl)ethoxy]phenyl]methyl]-2H-1-benzopyran-7-ol hydrochloride (CHF 4227), with improved in vivo estrogen agonist/antagonist effects. CHF 4227 binds with high affinity to the human estrogen receptor-alpha and -beta (dissociation constant K(i) = 0.017 and 0.099 nM, respectively). In immature rats, oral administration of CHF 4227 for 3 days inhibited the uterotrophic action of 17alpha-ethynyl estradiol (EE2) (ED(50) = 0.016 mg/kg. day); raloxifene was 25 times less potent as estrogen antagonist (ED(50) = 0.39 mg/kg. day), whereas both compounds were found to be devoid of uterotrophic activity. In line with its estrogen antagonist effect, CHF 4227 significantly prevented the development of dimethylbenz[a]anthracene (DMBA)-induced mammary tumors, the incidence being reduced from 87.5 to 26.3% 6 months after DMBA administration. In ovariectomized (OVX) rats treated orally for 4 weeks, CHF 4227 completely inhibited OVX effects on bone density (ED(50) = 0.003 mg/kg. day) and on serum osteocalcin levels. The protective effects on bone were comparable with those achieved with EE2, whereas raloxifene was less efficacious and 100 times less potent. CHF 4227 reduced serum cholesterol (ED(50) = 0.007 mg/kg. day) and had little to no stimulatory effects on uterine weight, uterine peroxidase activity, and endometrium epithelial thickness. In conclusion, CHF 4227 compares favorably in efficacy and potency with raloxifene in preventing bone loss and in antagonizing EE2 stimulation of the uterus. This profile along with the minimal uterine stimulation suggests a therapeutic advantage to CHF 4227 over EE2 or raloxifene for the treatment of postmenopausal women.

Synthesis, pharmacological evaluation, and structure-activity relationships of benzopyran derivatives with potent SERM activity.

The synthesis, binding affinity for estrogen receptor subtypes (ER alpha and ER beta) and pharmacological activity on rat uterus of a new class of potent ligands, characterized by a 3-phenylbenzopyran scaffold with a basic side chain in position 4, are reported. Some of these compounds, endowed with very high receptor affinity, showed potent inhibition of agonist-stimulated uterine growth, with no or limited proliferative effect. Binding affinity mostly depended on the nature and position of substituents at the 3-phenyl ring, while the uterine activity seems to be affected by basic chain length. Compound 9c (CHF4227) showed excellent binding affinity and antagonist activity on the uterus. The docking of benzopyran derivatives explained the structure-affinity relationships observed for 3-phenyl substitution: a small, hydrophobic 4'-substituent could interact with a small accessory binding cavity, while di-substitution at 4' and 3' led to some ER alpha selectivity. This selectivity can be ascribed to differences in amino acid composition and side chain conformation in the region accommodating the 3-phenyl ring at human ER alpha and ER beta ligand-binding domain.