A Dose-Ranging Study of the Novel Inhaled Dual PDE 3 and 4 Inhibitor Ensifentrine in Patients with COPD Receiving Maintenance Tiotropium Therapy

Pulmonology: What You May Have Missed in 2023

The field of pulmonology saw significant advances in 2023. The publications highlighted in this article address advances and changes in practice related to asthma, chronic obstructive pulmonary disease (COPD), interstitial lung disease, pleural disorders, and sleep-disordered breathing. One article reviews data examining the efficacy of vaccination against respiratory syncytial virus, a respiratory viral illness that has had devastating effects globally. Four studies evaluate the role of various therapies in COPD, including dupilumab, ensifentrine, pulmonary rehabilitation programs, and lung volume reduction versus endobronchial valves. Another study explores the effect on vascular events of positive-pressure ventilation in patients with sleep-disordered breathing and recent stroke. The use of combination therapy with rituximab and mycophenolate mofetil on progression-free survival in patients with nonspecific interstitial pneumonia is the topic of another study. We also highlight an update of clinical recommendations for the evaluation of patients with pleural disorders and a systematic review analyzing the effectiveness of inhaled corticosteroids as a supplement to dual therapy for COPD.

Ensifentrine, a Novel Phosphodiesterase 3 and 4 Inhibitor for the Treatment of Chronic Obstructive Pulmonary Disease: Randomized, Double-Blind, Placebo-controlled, Multicenter Phase III Trials (the ENHANCE Trials)

Rationale: Ensifentrine is a novel, selective, dual phosphodiesterase (PDE)3 and PDE4 inhibitor with bronchodilator and antiinflammatory effects. Replicate phase III trials of nebulized ensifentrine were conducted (ENHANCE-1 and ENHANCE-2) to assess these effects in patients with chronic obstructive pulmonary disease (COPD). Objectives: To evaluate the efficacy of ensifentrine compared with placebo for lung function, symptoms, quality of life, and exacerbations in patients with COPD. Methods: These phase III, multicenter, randomized, double-blind, parallel-group, placebo-controlled trials were conducted between September 2020 and December 2022 at 250 research centers and pulmonology practices in 17 countries. Patients aged 40-80 years with moderate to severe symptomatic COPD were enrolled. Measurements and Main Results: Totals of 760 (ENHANCE-1) and 789 (ENHANCE-2) patients were randomized and treated, with 69% and 55% receiving concomitant long-acting muscarinic antagonists or long-acting β2-agonists, respectively. Post-bronchodilator FEV1 percentage predicted values were 52% and 51% of predicted normal. Ensifentrine treatment significantly improved average FEV1 area under the curve at 0-12 hours versus placebo (ENHANCE-1, 87 ml [95% confidence interval, 55, 119]; ENHANCE-2, 94 ml [65, 124]; both P < 0.001). Ensifentrine treatment significantly improved symptoms (Evaluating Respiratory Symptoms) and quality of life (St. George's Respiratory Questionnaire) versus placebo at Week 24 in ENHANCE-1 but not in ENHANCE-2. Ensifentrine treatment reduced the rate of moderate or severe exacerbations versus placebo over 24 weeks (ENHANCE-1, rate ratio, 0.64 [0.40, 1.00]; P = 0.050; ENHANCE-2, rate ratio, 0.57 [0.38, 0.87]; P = 0.009) and increased time to first exacerbation (ENHANCE-1, hazard ratio, 0.62 [0.39, 0.97]; P = 0.038; ENHANCE-2, hazard ratio, 0.58 [0.38, 0.87]; P = 0.009). Adverse event rates were similar to those for placebo. Conclusions: Ensifentrine significantly improved lung function in both trials, with results supporting exacerbation rate and risk reduction in a broad COPD population and in addition to other classes of maintenance therapies. Clinical trial registered with www.

CLINICALTRIALS

gov and EudraCT (ENHANCE-1, www.

CLINICALTRIALS

gov identifier NCT04535986, EudraCT identifier 2020-002086-34; ENHANCE-2, www.

CLINICALTRIALS

gov identifier NCT04542057, EudraCT identifier 2020-002069-32).

Ensifentrine as a Novel, Inhaled Treatment for Patients with COPD

Ensifentrine is a novel, potent, and selective dual inhibitor of phosphodiesterase (PDE)3 and PDE4 designed for delivery by inhalation that combines effects on airway inflammation, bronchodilation and ciliary function in bronchial epithelia. In Phase 2 studies in subjects with COPD, ensifentrine demonstrated clinically meaningful bronchodilation and improvements in symptoms and health-related quality of life when administered alone or in combination with current standard of care therapies. Ensifentrine is currently in late-stage clinical development for the maintenance treatment of patients with COPD. This review summarizes non-clinical data as well as Phase 1 and Phase 2 efficacy and safety results of nebulized ensifentrine relevant to the maintenance treatment of patients with COPD.

Current Perspectives of Pharmacotherapies for COPD

Pharmacotherapies and avoidance of environmental/inhaled toxins are core to managing COPD. Compared to the drugs available 50 years ago, there has been substantial progress with COPD pharmacotherapies, but gaps in adherence and inhaler use persist. Personalizing inhaled pharmacotherapies is now possible with digital technologies by objectively documenting adherence and guiding inhaler technique. Another means to improve existing pharmacotherapies is through phenotyping and biomarkers. This is especially important considering the heterogeneity of the disease COPD. Blood eosinophils are now a recommended biomarker to guide use of inhaled corticosteroids and biologics in COPD. On the near horizon, we will see new inhaled medications as dual phosphodiesterase inhibitors, drugs to treat basic protein abnormalities as in alpha-1 antitrypsin deficiency that could have remarkable benefits, and biologic drugs targeting specific cell/mediator types in the COPD population. Characterization of COPD phenotypes, as asthma/COPD overlap and comorbid heart disease are vital to understand how to optimize pharmacotherapies. Importantly, we must determine how to optimize current medications; otherwise, we will repeat the same mistakes with new medications. But as we know so well, as we peel one layer of complexity, we encounter many more questions, all the while dedicated to limiting the burden of COPD.

Experimental drugs in clinical trials for COPD: Artificial Intelligence via Machine Learning approach to predict the successful advance from early-stage development to approval

INTRODUCTION

Therapeutic advances in drug therapy of chronic obstructive pulmonary disease (COPD) really effective in suppressing the pathological processes underlying the disease deterioration are still needed. Artificial Intelligence (AI) via Machine Learning (ML) may represent an effective tool to predict clinical development of investigational agents.

AREAL COVERED

Experimental drugs in Phase I and II development for COPD from early 2014 to late 2022 were identified in the ClinicalTrials.gov database. Different ML models, trained from prior knowledge on clinical trial success, were used to predict the probability that experimental drugs will successfully advance toward approval in COPD, according to Bayesian inference as follows: ≤25% low probability, >25% and ≤ 50% moderate probability, >50% and ≤ 75% high probability, and > 75% very high probability.

EXPERT OPINION

The Artificial Neural Network and Random Forest ML models indicated that, among the current experimental drugs in clinical trials for COPD, only the bifunctional muscarinic antagonist - β₂-adrenoceptor agonists (MABA) navafenterol and batefenterol, the inhaled corticosteroid (ICS)/MABA fluticasone furoate/batefenterol, and the bifunctional phosphodiesterase (PDE) 3/4 inhibitor ensifentrine resulted to have a moderate to very high probability of being approved in the next future, however not before 2025.

Recent advances predict a bright future for nebulizers

PURPOSE OF REVIEW

With the improvement in device technology and delivery methods of inhaled medications, along with development of novel compounds and recognition of the importance of personalized approach in the management of chronic airway diseases, nebulizers have not only maintained their place in the treatment hierarchy of airway disease but have also proven a vital platform for the development of new classes of drugs.

RECENT FINDINGS

This short review explores recent advances in nebulized drug delivery in chronic obstructive pulmonary disease and other chronic airway diseases, emphasizing the progress in nebulizer technology, physiologic advantages of nebulized drug delivery and the high versatility of currently available and developing nebulizer-delivered pharmacotherapies.

SUMMARY

Versatility and efficiency of nebulizers allows for a broad spectrum of existing and novel therapies to be clinically studied, facilitating the progress in phenotype-targeted pharmacotherapies in the management of chronic airway diseases.

CFTR Modulator Therapy for Rare CFTR Mutants

Cystic fibrosis (CF), the most common genetic disease among the Caucasian population, is caused by mutations in the gene encoding for the CF transmembrane conductance regulator (CFTR), a chloride epithelial channel whose dysfunction results in severe airway obstruction and inflammation, eventually leading to respiratory failure. The discovery of the CFTR gene in 1989 provided new insights into the basic genetic defect of CF and allowed the study of potential therapies targeting the aberrant protein. In recent years, the approval of “CFTR modulators”, the first molecules designed to selectively target the underlying molecular defects caused by specific CF-causing mutations, marked the beginning of a new era in CF treatment. These drugs have been demonstrated to significantly improve lung function and ameliorate the quality of life of many patients, especially those bearing the most common CFTR mutatant F508del. However, a substantial portion of CF subjects, accounting for ~20% of the European CF population, carry rare CFTR mutations and are still not eligible for CFTR modulator therapy, partly due to our limited understanding of the molecular defects associated with these genetic alterations. Thus, the implementation of models to study the phenotype of these rare CFTR mutations and their response to currently approved drugs, as well as to compounds under research and clinical development, is of key importance. The purpose of this review is to summarize the current knowledge on the potential of CFTR modulators in rescuing the function of rare CF-causing CFTR variants, focusing on both investigational and clinically approved molecules.

New drugs under development for COPD

The characteristic features of chronic obstructive pulmonary disease (COPD) include inflammation and remodelling of the lower airways and lung parenchyma together with activation of inflammatory and immune processes. Due to the increasing habit of cigarette smoking worldwide COPD prevalence is increasing globally. Current therapies are unable to prevent COPD progression in many patients or target many of its hallmark characteristics which may reflect the lack of adequate biomarkers to detect the heterogeneous clinical and molecular nature of COPD. In this chapter we review recent molecular data that may indicate novel pathways that underpin COPD subphenotypes and indicate potential improvements in the classes of drugs currently used to treat COPD. We also highlight the evidence for new drugs or approaches to treat COPD identified using molecular and other approaches including kinase inhibitors, cytokine- and chemokine-directed biologicals and small molecules, antioxidants and redox signalling pathway inhibitors, inhaled anti-infectious agents and senolytics. It is important to consider the phenotypes/molecular endotypes of COPD patients together with specific outcome measures to target new therapies to particular COPD subtypes. This will require greater understanding of COPD molecular pathologies and a focus on biomarkers of predicting disease subsets and responder/non-responder populations.

The future of inhalation therapy in chronic obstructive pulmonary disease

The inhaled route is critical for the administration of drugs to treat patients suffering from COPD, but there is still an unmet need for new and innovative inhalers to address some limitations of existing products that do not make them suitable for many COPD patients. The treatment of COPD, currently limited to the use of bronchodilators, corticosteroids, and antibiotics, requires a significant expansion of the therapeutic armamentarium that is closely linked to the widening of knowledge on the pathogenesis and evolution of COPD. The great interest in the development of new drugs that may be able to interfere in the natural history of the disease is leading to the synthesis of numerous new molecules, of which however only a few have entered the stages of clinical development. On the other hand, further improvement of inhaled drug delivery could be an interesting possibility because it targets the organ of interest directly, requires significantly less drug to exert the pharmacological effect and, by lowering the amount of drug needed, reduces the cost of therapy. Unfortunately, however, the development of new inhaled drugs for use in COPD is currently too slow.

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Inhalation therapy is central when treating patients with COPD.

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There has been and still there is a substantial evolution in inhaler devices.

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New targets possibly useful for the development of new drugs have been identified.

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Only very few of new drugs are being evaluated for inhaled administration.

Modification of Apremilast from Pills to Aerosol a Future Concept

Background: Inhaled drugs have been available in the market for several years and for several diseases. Drugs for chronic obstructive pulmonary disease, cystic fibrosis, and diabetes have been used for several years. In the field of drug modification, these drugs range from tablets to aerosol. Methods: Milling as used to break down the tablets to powder and nebulisers are used to produce aerosol droplets. A mastersizer was used to measure the mass median aerodynamic diameter of the aerosol droplets. Results: Apremilast produced mmad diameters (2.43 μm) without any statistical difference between the different jet-nebulizers. The residual cup B contributed to greater mmad diameters as the 95% interval of mean values, based on those the ANOVA mean square clearly indicated, followed by cups C and F. The previous interval plot is much better clarified when the interaction means between drug and residual cap are plotted. The residual cups B, C and F produce mmad between (2.0–3.2). Conclusion: In the current research study we demonstrated our methodology to create apremilast powder and produce apremilast aerosol droplets with different nebulisers and residual cups.

Inhaled Dual Phosphodiesterase 3/4 Inhibitors for the Treatment of Patients with COPD: A Short Review

Current pharmacological treatments for chronic obstructive pulmonary disease (COPD) are mostly limited to inhaled bronchodilators and corticosteroids. Azithromycin can contribute to exacerbation prevention. Roflumilast, a phosphodiesterase (PDE) 4 inhibitor administered orally, also prevents exacerbations in selected patients with chronic bronchitis, recurrent exacerbations, severe airflow limitation and concomitant therapy with long-acting inhaled bronchodilators. This outcome likely results from anti-inflammatory effects since PDE4 is expressed by all inflammatory cell types involved in COPD. The use of this agent is, however, limited by side-effects, particularly nausea and diarrhea. To address remaining unmet needs and enrich therapeutic options for patients with COPD, inhaled dual PDE3/4 inhibitors have been developed, with the aim of enhancing bronchodilation through PDE3 inhibition and modulating inflammation and mucus production though PDE4 inhibition, thus producing a potentially synergistic effect on airway calibre. Experimental preclinical data confirmed these effects in vitro and in animal models. At present, RPL554/ensifentrine is the only agent of this family in clinical development. It decreases sputum markers of both neutrophilic and eosinophilic inflammation in patients with COPD. Clinical Phase II trials confirmed its bronchodilator effect and demonstrated clinically meaningful symptom relief and quality of life improvements in these patients. The safety profile appears satisfactory, with less effects on heart rate and blood pressure than salbutamol and no other side effect. Altogether, these data suggest that ensifentrine could have a role in COPD management, especially in addition to inhaled long-acting bronchodilators with or without corticosteroids since experimental studies suggest potentiation of ensifentrine effects by these agents. However, results from ongoing and future Phase III studies are needed to confirm both beneficial effects and favourable safety profile on a larger scale and assess other outcomes including exacerbations, lung function decline, comorbidities and mortality.