Tanimilast, A Novel Inhaled Pde4 Inhibitor for the Treatment of Asthma and Chronic Obstructive Pulmonary Disease.

Chronic respiratory diseases are the third leading cause of death, behind cardiovascular diseases and cancer, affecting approximately 550 million of people all over the world. Most of the chronic respiratory diseases are attributable to asthma and chronic obstructive pulmonary disease (COPD) with this latter being the major cause of deaths. Despite differences in etiology and symptoms, a common feature of asthma and COPD is an underlying degree of airways inflammation. The nature and severity of this inflammation might differ between and within different respiratory conditions and pharmacological anti-inflammatory treatments are unlikely to be effective in all patients. A precision medicine approach is needed to selectively target patients to increase the chance of therapeutic success. Inhibitors of the phosphodiesterase 4 (PDE4) enzyme like the oral PDE4 inhibitor roflumilast have shown a potential to reduce inflammatory-mediated processes and the frequency of exacerbations in certain groups of COPD patients with a chronic bronchitis phenotype. However, roflumilast use is dampened by class related side effects as nausea, diarrhea, weight loss and abdominal pain, resulting in both substantial treatment discontinuation in clinical practice and withdrawal from clinical trials. This has prompted the search for PDE4 inhibitors to be given by inhalation to reduce the systemic exposure (and thus optimize the systemic safety) and maximize the therapeutic effect in the lung. Tanimilast (international non-proprietary name of CHF6001) is a novel highly potent and selective inhaled PDE4 inhibitor with proven anti-inflammatory properties in various inflammatory cells, including leukocytes derived from asthma and COPD patients, as well as in experimental rodent models of pulmonary inflammation. Inhaled tanimilast has reached phase III clinical development by showing promising pharmacodynamic results associated with a good tolerability and safety profile, with no evidence of PDE4 inhibitors class-related side effects. In this review we will discuss the main outcomes of preclinical and clinical studies conducted during tanimilast development, with particular emphasis on the characterization of the pharmacodynamic profile that led to the identification of target populations with increased therapeutic potential in inflammatory respiratory diseases.

COPD patients with chronic bronchitis and higher sputum eosinophil counts show increased type-2 and PDE4 gene expression in sputum.

Chronic obstructive pulmonary disease (COPD) patients with higher eosinophil counts are associated with increased clinical response to phosphodiesterase-4-inhibitors (PDE4i). However, the underlying inflammatory mechanisms associated with this increased response is not yet elucidated. This post hoc analysis focused on sputum gene expression in patients with chronic bronchitis who underwent 32-day treatment with two doses of the inhaled PDE4i CHF6001 (tanimilast) or placebo on top of triple therapy. Biological characterization and treatment effects were assessed between patients with different sputum eosinophil levels (eosinophilhigh  ≥ 3%; eosinophillow  < 3%) at baseline (primary samples) or at the end of the treatment of the placebo arm (validation samples). Forty-one genes were differentially expressed in primary samples (p-adjusted for false discovery rate < 0.05); all up-regulated in eosinophilhigh patients and functionally enriched for type-2 and PDE4 inflammatory processes. Eleven out of nineteen genes having immune system biological processes annotations including IL5RA, ALOX15, IL1RL1, CLC, GATA1 and PDE4D were replicated using validation samples. The expression of a number of these inflammatory mediators was reduced by tanimilast treatment, with greater effects observed in eosinophilhigh patients. These findings suggest that type-2 and PDE4 overexpression in COPD patients with higher sputum eosinophil counts contribute to the differential clinical response to PDE4i observed in previous clinical trials.

Efficacy and safety of CHF6001, a novel inhaled PDE4 inhibitor in COPD: the PIONEER study.

BACKGROUND: This study evaluated the efficacy, safety and tolerability of the novel inhaled phosphodiesterase-4 inhibitor CHF6001 added-on to formoterol in patients with chronic obstructive pulmonary disease (COPD). METHODS: Randomised, double-blind, placebo- and active-controlled, parallel-group study. Eligible patients had symptomatic COPD, post-bronchodilator forced expiratory volume in 1 s (FEV1) 30-70% predicted, and history of ≥1 moderate/severe exacerbation. Patients were randomised to extrafine CHF6001 400, 800, 1200 or 1600 µg twice daily (BID), budesonide, or placebo for 24 weeks. PRIMARY OBJECTIVES: To investigate CHF6001 dose-response for pre-dose FEV1 after 12 weeks, and to identify the optimal dose. Moderate-to-severe exacerbations were a secondary endpoint. RESULTS: Of 1130 patients randomised, 91.9% completed. Changes from baseline in pre-dose FEV1 at Week 12 were small in all groups (including budesonide), with no CHF6001 dose-response, and no significant treatment-placebo differences. For moderate-to-severe exacerbations, CHF6001 rate reductions versus placebo were 13-28% (non-significant). In post-hoc analyses, CHF6001 effects were larger in patients with a chronic bronchitis phenotype (rate reductions versus placebo 24-37%; non-significant), and were further increased in patients with chronic bronchitis and eosinophil count ≥150 cells/µL (49-73%, statistically significant for CHF6001 800 and 1600 µg BID). CHF6001 was well tolerated with no safety signal (including in terms of gastrointestinal adverse events). CONCLUSIONS: CHF6001 had no effect in the primary lung function analysis, although was well-tolerated with no gastrointestinal adverse event signal. Post-hoc analyses focused on exacerbation risk indicate specific patient subgroups who may receive particular benefit from CHF6001. TRIAL REGISTRATION: ClinicalTrials.gov ( NCT02986321 ). Registered 8 Dec 2016.

Sputum and blood transcriptomics characterisation of the inhaled PDE4 inhibitor CHF6001 on top of triple therapy in patients with chronic bronchitis.

BACKGROUND: Although phosphodiesterase-4 (PDE4) inhibitors have been shown to reduce COPD exacerbation rate, their biological mechanism of action is not completely elucidated at the molecular level. We aimed to characterise the whole genome gene expression profile of the inhaled PDE4-inhibitor CHF6001 on top of triple therapy in sputum cells and whole blood of patients with COPD and chronic bronchitis. METHODS: Whole genome gene expression analysis was carried out by microarray in 54 patients before and after 32 days treatment with CHF6001 800 and 1600 µg and placebo twice daily (BID) in a randomised crossover study. RESULTS: CHF6001 had a strong effect in sputum, with 1471 and 2598 significantly differentially-expressed probe-sets relative to placebo (p-adjusted for False Discovery Rate < 0.05) with 800 and 1600 µg BID, respectively. Functional enrichment analysis showed significant modulation of key inflammatory pathways involved in cytokine activity, pathogen-associated-pattern-recognition activity, oxidative stress and vitamin D with associated inhibition of downstream inflammatory effectors. A large number of pro-inflammatory genes coding for cytokines and matrix-metalloproteinases were significantly differentially expressed for both doses; the majority (> 87%) were downregulated, including macrophage inflammatory protein-1-alpha and 1-beta, interleukin-27-beta, interleukin-12-beta, interleukin-32, tumour necrosis factor-alpha-induced-protein-8, ligand-superfamily-member-15, and matrix-metalloproteinases-7,12 and 14. The effect in blood was not significant. CONCLUSIONS: Inhaled PDE4 inhibition by CHF6001 on top of triple therapy in patients with COPD and chronic bronchitis significantly modulated key inflammatory targets and pathways in the lung but not in blood. Mechanistically these findings support a targeted effect in the lung while minimising unwanted systemic class-effects. TRIAL REGISTRATION: ClinicalTrial.gov, EudraCT, 2015-005550-35. Registered 15 July 2016.

Effect of the inhaled PDE4 inhibitor CHF6001 on biomarkers of inflammation in COPD.

BACKGROUND: CHF6001 is a novel inhaled phosphodiesterase-4 inhibitor. This Phase IIa study assessed the effects of CHF6001 on markers of inflammation in induced sputum and blood in patients with chronic obstructive pulmonary disease (COPD). METHODS: This was a multicentre, three-period (each 32 days), three-way, placebo-controlled, double-blind, complete-block crossover study. Eligible patients had COPD, chronic bronchitis, and were receiving inhaled triple therapy for ≥2 months. Patients received CHF6001 800 or 1600 µg, or matching placebo twice daily via multi-dose dry-powder inhaler (NEXThaler). Induced sputum was collected pre-dose on Day 1, and post-dose on Days 20, 26 and 32. Blood was sampled pre-dose on Day 1, and pre- and post-dose on Day 32. RESULTS: Of 61 randomised patients, 54 (88.5%) completed the study. There were no significant differences between groups for overall sputum cell count, or absolute numbers of neutrophils, eosinophils or lymphocytes. CHF6001 800 µg significantly decreased the absolute number and percentage of macrophages vs placebo. In sputum, compared with placebo both CHF6001 doses significantly decreased leukotriene B4, C-X-C motif chemokine ligand 8, macrophage inflammatory protein 1ß, matrix metalloproteinase 9, and tumour necrosis factor α (TNFα). In blood, both CHF6001 doses significantly decreased serum surfactant protein D vs placebo. CHF6001 1600 µg significantly decreased TNFα ex-vivo (after incubation with lipopolysaccharide). CONCLUSION: The data from this study show that CHF6001 inhaled twice daily has anti-inflammatory effects in the lungs of patients with COPD already treated with triple inhaled therapy. TRIAL REGISTRATION: The study is registered on ClinicalTrials.gov ( NCT03004417 ).

Dose-response of an extrafine dry powder inhaler formulation of glycopyrronium bromide: randomized, double-blind, placebo-controlled, dose-ranging study (GlycoNEXT).

Introduction: An extrafine formulation of the long-acting muscarinic antagonist, glycopyrronium bromide (GB), has been developed for delivery via the NEXThaler dry powder inhaler (DPI). This study assessed the bronchodilator efficacy and safety of different doses of this formulation in patients with COPD to identify the optimal dose for further development. Patients and methods: This was a multicenter, randomized, double-blind, placebo-controlled, incomplete block, three-way crossover study, including three 28-day treatment periods, each separated by a 21-day washout period. Eligible patients had a diagnosis of COPD and post-bronchodilator forced expiratory volume in 1 s (FEV1) 40%-70% predicted. Treatments administered were GB 6.25, 12.5, 25 and 50 µg or matched placebo; all were given twice daily (BID) via DPI, with spirometry assessed on Days 1 and 28 of each treatment period. The primary end point was FEV1 area under the curve from 0 to 12 h (AUC0-12 h) on Day 28. Results: A total of 202 patients were randomized (61% male, mean age 62.6 years), with 178 (88%) completing all the three treatment periods. For the primary end point, all the four GB doses were superior to placebo (p<0.001) with mean differences (95% CI) of 114 (74, 154), 125 (85, 166), 143 (104, 183) and 187 (147, 228) mL for GB 6.25, 12.5, 25 and 50 µg BID, respectively. All four GB doses were also statistically superior to placebo for all secondary efficacy end points, showing clear dose-response relationships for most of the endpoints. Accordingly, GB 25 µg BID met the criteria for the minimally acceptable dose. Adverse events were reported by 15.5, 16.2, 10.9 and 14.3% of patients receiving GB 6.25, 12.5, 25 and 50 µg BID, respectively, and 14.8% receiving placebo. Conclusion: This study supports the selection of GB 25 µg BID as the minimal effective dose for patients with COPD when delivered with this extrafine DPI formulation.