Asthma, COPD & Interstitial Lung Disease
A comprehensive analysis of the pulmonology clinical trial landscape — from spirometry standardization and exacerbation-driven endpoints to biologic stratification and pipeline dynamics across severe asthma, COPD, IPF, and emerging respiratory therapies.
The Pulmonology Trial Landscape in 2026
Pulmonology has emerged as one of the most dynamic therapeutic areas in clinical research, driven by an explosion of biologic therapies for severe asthma, a renewed focus on disease-modifying approaches for COPD, and continued innovation in anti-fibrotic strategies for interstitial lung disease. Within the Clinitiative network, pulmonology represents a strategically important portfolio with 20 active studies spanning moderate-to-severe asthma, eosinophilic asthma, COPD exacerbation reduction, idiopathic pulmonary fibrosis (IPF), non-IPF interstitial lung disease (ILD), pulmonary hypertension, cystic fibrosis, and bronchiectasis. This breadth reflects both the significant unmet medical need across respiratory medicine and the accelerating pace of therapeutic innovation targeting airway inflammation, structural remodeling, and fibrotic pathways.
The distribution of active studies across our network reflects current pipeline dynamics and sponsor priorities: moderate-to-severe and eosinophilic asthma leads with 8 active protocols, driven by next-generation biologic agents targeting TSLP, IL-33, and IL-25 pathways beyond the established anti-IL-5 and anti-IL-4R classes. COPD follows with 6 active studies emphasizing exacerbation reduction, mucus hypersecretion, and anti-inflammatory mechanisms beyond inhaled corticosteroids. IPF and non-IPF ILD account for 4 studies focused on combination anti-fibrotic strategies and emerging therapies for autoimmune-associated ILD. The remaining 2 studies span pulmonary arterial hypertension, cystic fibrosis, and bronchiectasis — rare but high-impact conditions where novel modulator therapies and anti-infective approaches are transforming the treatment paradigm.
Biologics have fundamentally transformed the severe asthma treatment landscape, and the clinical trial implications are profound. With multiple approved biologics now available — including omalizumab, mepolizumab, benralizumab, dupilumab, and tezepelumab — the biologic-naive severe asthma population is progressively shrinking. COPD exacerbation reduction trials continue to grow in volume as sponsors pursue anti-inflammatory strategies that extend beyond traditional bronchodilator-ICS combinations. IPF remains one of the most challenging enrollment landscapes in all of clinical research due to the rarity of the condition, the narrow diagnostic window, and the availability of approved anti-fibrotic therapies that limit placebo-controlled study designs.
Key Performance Metrics
Network-wide benchmarks from our pulmonology portfolio provide critical reference points for study planning, site performance evaluation, and enrollment forecasting across respiratory indications.
Across all pulmonology indications, our network sites achieve a median enrollment rate of 2.0 patients per site per month. Asthma studies consistently outperform this benchmark at 2.6 patients per site per month, benefiting from large patient populations and strong allergy/immunology referral networks. COPD studies average 1.8 patients per site per month, with enrollment velocity closely tied to access to pulmonary rehabilitation programs and hospital discharge pathways. IPF studies face the greatest enrollment challenge at 0.8 patients per site per month, reflecting the rarity of the condition and the narrow window of diagnostic confirmation required for protocol eligibility.
Screen failure rates across the pulmonology portfolio average 32%, with spirometry reversibility requirements serving as the primary driver in asthma studies. Protocols requiring demonstration of a minimum 12% and 200 mL improvement in FEV1 post-bronchodilator exclude a significant proportion of otherwise eligible patients, particularly those on maintenance controller therapy. Eosinophil threshold requirements for biologic studies further narrow the eligible population, with blood eosinophil counts of 300 cells per microliter or higher disqualifying 40-50% of screened patients in some protocols. COPD studies experience lower screen failure rates at 25-28%, while IPF studies face unique challenges with HRCT pattern confirmation requirements.
From contract execution to first patient enrolled, pulmonology sites within the network achieve a median startup time of 12.2 weeks. This moderate timeline reflects the need for pulmonary function testing equipment calibration and validation, spirometer standardization across sites, and training of PFT technicians to meet ATS/ERS quality criteria. Sites with established pulmonary function laboratories and prior respiratory trial experience consistently achieve startup 2-3 weeks faster than sites requiring new equipment installation or technician certification for study-specific procedures.
The overall patient retention rate across pulmonology studies is 80%, with significant variation by disease area. Asthma studies demonstrate the highest retention at 86%, reflecting the chronic but generally manageable nature of the disease and the appeal of biologic therapies for patients with poorly controlled symptoms. COPD retention is lower at 74%, driven by disease exacerbations requiring hospitalization, cardiovascular comorbidity events, and the overall frailty of the COPD population. IPF and ILD studies maintain moderate retention at 78%, with disease progression and transplant referral representing the primary drivers of early discontinuation.
Network Capabilities
Executing pulmonology trials at the precision and reproducibility required by modern respiratory protocols demands specialized infrastructure, certified technical staff, and standardized operational processes. Our network has been developed to ensure deep pulmonology-specific capabilities that meet the rigorous demands of spirometry-based endpoints, biomarker-driven enrollment, and advanced imaging assessments.
Pulmonary Function Testing
Spirometry forms the backbone of nearly every pulmonology clinical trial, and the quality of pulmonary function testing (PFT) data directly determines study success. Our network sites maintain fully ATS/ERS-standardized pulmonary function laboratories equipped for spirometry, body plethysmography, lung diffusion capacity (DLCO) testing, fractional exhaled nitric oxide (FeNO) measurement, and bronchial challenge testing including methacholine and mannitol provocation. All PFT technicians complete annual competency certification and undergo protocol-specific training for each new study to ensure reproducibility across sites and timepoints.
For studies utilizing centralized spirometry over-read services, our sites achieve a first-attempt acceptability rate exceeding 90% — significantly above the industry average of 75-80%. This quality advantage reduces the need for repeat testing visits, accelerates screening timelines, and minimizes patient burden. All spirometry equipment undergoes daily biological control testing and quarterly calibration verification with full audit trails maintained for regulatory inspection readiness.
Induced Sputum & Airway Biomarkers
Induced sputum analysis has become an increasingly important endpoint and stratification tool in asthma and COPD trials, particularly for studies targeting eosinophilic or neutrophilic airway inflammation. Our network sites maintain sputum induction capabilities using standardized hypertonic saline nebulization protocols, with on-site sputum processing within 2 hours of collection to preserve cell viability. Trained laboratory technicians perform differential cell counts, eosinophil percentage quantification, and cytokine panel processing for translational biomarker assessments.
Beyond sputum analysis, our sites support a comprehensive array of airway biomarker assessments including blood eosinophil counts, serum IgE levels, periostin measurement, FeNO testing, and emerging biomarkers such as serum IL-5, IL-13, and TSLP pathway markers. This biomarker infrastructure enables rapid phenotyping of patients during screening and supports the increasingly granular stratification requirements of modern biologic asthma trials.
High-Resolution CT & Imaging
High-resolution computed tomography (HRCT) is essential for ILD diagnosis, disease staging, and longitudinal monitoring in fibrotic lung disease trials. Our network sites maintain access to HRCT protocols optimized for interstitial lung disease assessment, including thin-slice volumetric acquisition, prone imaging to distinguish dependent atelectasis from early fibrosis, and expiratory phase imaging for air trapping quantification. All imaging protocols are standardized across sites and validated by imaging core laboratories to ensure consistency of measurements across timepoints and study visits.
Quantitative CT analysis — including automated lung density measurement, fibrosis scoring, and emphysema quantification — is increasingly being incorporated as an endpoint in both ILD and COPD trials. Our sites support direct image upload to imaging core laboratories through established DICOM transfer pathways, with imaging coordinators ensuring protocol-compliant acquisition parameters and timely image submission for central read adjudication.
Home Monitoring & Digital Endpoints
The integration of digital health technologies into pulmonology trials is accelerating rapidly, with home-based peak flow monitoring, electronic symptom diaries, wearable respiratory rate sensors, and smart inhaler tracking platforms becoming standard components of modern respiratory protocols. Our network sites are experienced in deploying and managing these technologies, including patient training on device usage, troubleshooting connectivity issues, and monitoring compliance with daily recording requirements. Sites maintain dedicated digital health coordinators who track adherence metrics and intervene proactively when data gaps are detected.
Smart inhaler technology represents a particularly important advancement for asthma and COPD studies, providing objective medication adherence data that has historically been unreliable when based on patient self-report. Our sites have deployed smart inhaler platforms across multiple protocols, achieving average adherence monitoring compliance rates exceeding 85%. This infrastructure supports both the collection of adherence data as a study endpoint and the identification of non-adherent patients for targeted intervention during the study conduct period.
Enrollment Dynamics
Pulmonology enrollment patterns are shaped by a distinctive set of factors including seasonal disease variability, biologic treatment history, referral network dependencies, and the unique challenges of recruiting for rare fibrotic lung conditions. Understanding these dynamics is essential for realistic enrollment planning and effective site management across respiratory indications.
The large prevalence of asthma in the general population — affecting approximately 25 million Americans — creates a substantial addressable patient pool, but the subset eligible for biologic clinical trials is considerably smaller. Moderate-to-severe asthma studies requiring evidence of uncontrolled disease despite medium-to-high dose ICS/LABA therapy typically find that only 15-20% of screened patients meet both the clinical and biomarker eligibility criteria. For eosinophilic asthma studies requiring blood eosinophil counts above 300 cells per microliter, the eligible population narrows further. Our network addresses this through established allergy and asthma referral networks that channel biologic-eligible patients from community allergists and pulmonologists into participating research sites.
COPD recruitment benefits from strong connections to pulmonary rehabilitation programs, hospital discharge pathways following COPD exacerbation admissions, and community pulmonology practices with large chronic disease populations. Exacerbation history requirements — typically mandating at least one or two moderate-to-severe exacerbations in the prior 12 months — represent the primary enrollment bottleneck in COPD trials. Our network leverages electronic health record (EHR) mining tools to identify patients with documented exacerbation histories, significantly accelerating the pre-screening identification process.
IPF enrollment remains among the most challenging in all of clinical research. The estimated prevalence of IPF is only 13-20 per 100,000 population, and many patients are diagnosed at advanced stages when they may not meet study entry criteria for pulmonary function thresholds. Our network recruits IPF patients through dedicated ILD clinics, multidisciplinary ILD conferences, pulmonary fibrosis foundation registries, and referral relationships with community pulmonologists who may encounter suspected ILD patients requiring subspecialty confirmation. Seasonal exacerbation patterns also influence enrollment velocity across all respiratory indications, with viral respiratory season (October through March) consistently driving higher exacerbation-related screening activity.
Key Challenges in Pulmonology Trial Execution
The evolving complexity of respiratory protocols presents operational challenges that require specialized strategies, infrastructure, and clinical expertise to address effectively.
Spirometry Standardization & Reproducibility
Spirometry quality is the single most critical determinant of data integrity in pulmonology trials. The ATS/ERS acceptability and repeatability criteria require that at least three acceptable maneuvers be obtained with the two largest FEV1 and FVC values within 150 mL of each other. Achieving this standard consistently across multiple sites and timepoints demands rigorous technician training, ongoing quality oversight, and real-time over-read feedback. Our network implements a centralized spirometry quality management program that includes protocol-specific technician certification, automated quality grading at the point of collection, and same-day over-read feedback from central PFT reviewers. Sites participating in this program achieve ATS/ERS acceptability rates exceeding 92%, compared to industry averages of 75-80%, directly reducing data queries, repeat visit requirements, and the risk of primary endpoint measurement variability undermining study power.
Exacerbation-Driven Endpoint Designs
A growing proportion of asthma and COPD trials use exacerbation reduction as a primary or key secondary endpoint, which introduces significant study design and operational complexity. Exacerbation endpoints are inherently variable, influenced by seasonal viral patterns, environmental triggers, and medication adherence. Studies must enroll patients with a documented history of exacerbations to ensure sufficient event rates, yet verifying exacerbation history from medical records is often inconsistent and time-consuming. Baseline exacerbation requirements of two or more moderate-to-severe exacerbations in the prior year can exclude 50-60% of otherwise eligible COPD patients. Our network addresses this through standardized exacerbation documentation protocols, EHR-based pre-screening tools, and seasonal enrollment planning that aligns recruitment windows with peak exacerbation periods to maximize the probability of capturing events during the study treatment period.
Biologic-Experienced Patient Pools
The progressive adoption of biologic therapies for severe asthma is depleting the biologic-naive patient population that many clinical trials require. With five approved biologic classes now available for severe asthma, identifying patients who have never received biologic therapy and who still meet the severity and biomarker criteria for new biologic studies is increasingly difficult. Some protocols now permit biologic-experienced patients with mandated washout periods, but these designs introduce additional complexity around washout adequacy, rebound exacerbation risk, and baseline biomarker interpretation. Our network tracks biologic treatment history across participating sites and maintains registries of biologic-naive severe asthma patients who have been identified through allergy and pulmonology referral networks but have not yet initiated commercially available biologic therapy, providing a targeted recruitment channel for studies requiring biologic-naive populations.
Comorbidity Burden in COPD
COPD patients present one of the highest comorbidity burdens of any clinical trial population. Cardiovascular disease (ischemic heart disease, heart failure, atrial fibrillation), metabolic syndrome (diabetes, obesity), osteoporosis, anxiety, depression, and gastroesophageal reflux disease are all significantly more prevalent in COPD populations compared to age-matched controls. These comorbidities complicate eligibility assessment, increase the risk of adverse events unrelated to study medication, and contribute to the higher discontinuation rates observed in COPD trials. Our network sites employ dedicated COPD research coordinators who are trained to navigate complex comorbidity profiles, coordinate with multiple specialist providers, and manage the polypharmacy considerations that are inherent in this population. Sites also maintain established referral relationships with cardiology, endocrinology, and psychiatry to facilitate rapid evaluation of comorbidity-related adverse events during study conduct.
Pipeline Analysis
The pulmonology development pipeline continues to expand with innovative mechanisms of action targeting airway inflammation, structural remodeling, and fibrotic pathways. Several therapeutic modalities are driving significant shifts in trial design, site requirements, and enrollment planning across respiratory indications.
Next-Generation Asthma Biologics
While the first wave of biologic approvals targeted downstream Type 2 inflammatory mediators (IL-5, IL-4/IL-13, IgE), the next generation of asthma biologics is moving upstream to target epithelial alarmins — TSLP, IL-33, and IL-25 — that initiate and amplify the inflammatory cascade. These upstream targets offer the potential for broader efficacy across both eosinophilic and non-eosinophilic asthma phenotypes, potentially addressing the significant unmet need in patients who do not respond to existing biologics. Tezepelumab, the first approved anti-TSLP therapy, has opened this class, and multiple anti-IL-33 and anti-IL-25 agents are now in Phase II and Phase III development. These studies require careful phenotyping of patients at baseline, including assessment of Type 2 biomarkers (eosinophils, FeNO, IgE, periostin) and emerging non-Type 2 markers to evaluate efficacy across inflammatory endotypes.
COPD Disease-Modifying Therapies
COPD therapy has historically been limited to symptom management through bronchodilators and inhaled corticosteroids, with no approved disease-modifying treatments that alter the progressive decline in lung function. The pipeline is now shifting toward agents that target the underlying biology of COPD progression, including novel anti-inflammatory pathways beyond ICS (PDE4 inhibitors, p38 MAPK inhibitors, PI3K-delta inhibitors), senolytic agents that clear senescent cells contributing to lung tissue destruction, and epithelial repair therapies aimed at restoring damaged airway epithelium. These disease-modifying approaches require longer study durations, serial spirometry endpoints to demonstrate FEV1 decline attenuation, and careful adjudication of exacerbation events over extended follow-up periods. Sites must be prepared for 52-week or longer treatment periods with frequent PFT assessments and robust patient retention strategies.
Anti-Fibrotic Innovation for ILD
The approval of pirfenidone and nintedanib established anti-fibrotic therapy as the standard of care for IPF, but these agents slow rather than halt disease progression and are associated with significant gastrointestinal side effects that limit tolerability. The next generation of anti-fibrotic therapies includes combination approaches that pair existing anti-fibrotics with novel mechanisms (autotaxin inhibitors, galectin-3 inhibitors, integrin antagonists, and connective tissue growth factor inhibitors), as well as therapies specifically designed for non-IPF progressive fibrosing ILD — including autoimmune ILD associated with rheumatoid arthritis, systemic sclerosis, and inflammatory myopathies. These studies require multidisciplinary ILD expertise for patient selection, HRCT-based staging, and careful monitoring for both disease progression and treatment-related hepatotoxicity. The expansion beyond IPF into broader ILD populations represents a significant enrollment opportunity for sites with established rheumatology and pulmonology collaboration pathways.
Precision Inhaler & Device Technologies
The inhaler device landscape is undergoing a transformation driven by smart inhaler technology, soft-mist inhalers, and digital adherence monitoring platforms that provide objective data on medication usage patterns. Clinical trials evaluating these devices require sites to manage device training for patients, troubleshoot technical issues with connected devices, and integrate digital adherence data streams into the study database alongside traditional clinical endpoints. Smart inhalers equipped with Bluetooth connectivity and dose counters enable real-time monitoring of inhaler technique and adherence, providing data that has historically been unavailable in respiratory trials. Our network sites have established digital health workflows that support the deployment of these technologies, including patient training protocols, device inventory management, and dedicated technical support for connectivity and data upload issues. This infrastructure positions our sites to execute the growing number of device- plus-drug combination studies in the respiratory pipeline.
Site Requirements for Pulmonology Excellence
The infrastructure, staffing, and operational processes required to execute modern pulmonology protocols at the highest level of data quality and patient safety.
Dedicated pulmonary function laboratory equipped with ATS/ERS- compliant spirometers, body plethysmograph, DLCO testing system, FeNO analyzer, and bronchial challenge testing capabilities. Daily biological control testing, quarterly calibration verification, and centralized over-read integration for study-quality spirometry data across all timepoints.
On-site induced sputum processing capabilities with trained laboratory technicians for differential cell counts, eosinophil quantification, and cytokine panel preparation. Hypertonic saline nebulization equipment, processing within 2 hours of collection, and specimen handling protocols for translational biomarker shipment to central laboratories.
On-site or rapid-access HRCT capabilities with ILD-optimized acquisition protocols including thin-slice volumetric imaging, prone positioning, and expiratory phase sequences. Standardized imaging protocols validated by imaging core laboratories, DICOM transfer pathways, and imaging coordinators ensuring protocol-compliant acquisition across all study visits.
Infrastructure for deploying and managing home-based digital health technologies including peak flow meters, electronic symptom diaries, wearable respiratory rate monitors, and smart inhaler platforms. Dedicated digital health coordinators for patient training, adherence monitoring, device troubleshooting, and data quality oversight throughout the study conduct period.
Research pharmacy with temperature-controlled storage for biologic investigational products, nebulization solution preparation, inhaler device inventory management, and drug accountability systems compliant with sponsor and regulatory audit standards. Pharmacist oversight of inhaler technique training and adherence counseling for inhaled therapies.
Dedicated pulmonology clinical research coordinators with respiratory-specific training, certified PFT technicians meeting ATS/ERS competency standards, research nurses experienced in biologic administration and anaphylaxis management, and regulatory coordinators managing IRB submissions and protocol amendments across multiple active respiratory protocols.
Discuss Your Pulmonology Program
Connect with our team to explore site capabilities, enrollment strategies, and spirometry infrastructure for your pulmonology clinical development program.