Meaningful Endpoints for Idiopathic Pulmonary Fibrosis (IPF) Clinical Trials: Emphasis on 'Feels, Functions, Survives'. Report of a Collaborative Discussion in a Symposium with Direct Engagement from Representatives of Patients, Investigators, the National Institutes of Health, a Patient Advocacy Organization, and a Regulatory Agency.

Background: Idiopathic pulmonary fibrosis (IPF) carries significant mortality and unpredictable progression, with limited therapeutic options. Designing trials with patient-meaningful endpoints, enhancing the reliability and interpretability of results, and streamlining the regulatory approval process are of critical importance to advancing clinical care in IPF. Methods: A landmark in-person symposium in June 2023 assembled 43 participants from the US and internationally, including patients with IPF, investigators, and regulatory representatives, to discuss the immediate future of IPF clinical trial endpoints. Patient advocates were central to discussions, which evaluated endpoints according to regulatory standards and the FDA's 'feels, functions, survives' criteria. Results: Three themes emerged: 1) consensus on endpoints mirroring the lived experiences of patients with IPF; 2) consideration of replacing forced vital capacity (FVC) as the primary endpoint, potentially by composite endpoints that include 'feels, functions, survives' measures or FVC as components; 3) support for simplified, user-friendly patient-reported outcomes (PROs) as either components of primary composite endpoints or key secondary endpoints, supplemented by functional tests as secondary endpoints and novel biomarkers as supportive measures (FDA Guidance for Industry (Multiple Endpoints in Clinical Trials) available at: https://www.fda.gov/media/162416/download). Conclusions: This report, detailing the proceedings of this pivotal symposium, suggests a potential turning point in designing future IPF clinical trials more attuned to outcomes meaningful to patients, and documents the collective agreement across multidisciplinary stakeholders on the importance of anchoring IPF trial endpoints on real patient experiences-namely, how they feel, function, and survive. There is considerable optimism that clinical care in IPF will progress through trials focused on patient-centric insights, ultimately guiding transformative treatment strategies to enhance patients' quality of life and survival.

Nintedanib in Progressive Pulmonary Fibrosis: A Systematic Review and Meta-Analysis.

Background: The American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax convened to update clinical practice guidelines for interstitial lung disease (ILD). Objective: To conduct a systematic review to evaluate existing ILD literature to determine whether patients with progressive pulmonary fibrosis (PPF) should be treated with the antifibrotic nintedanib. Data Sources: A literature search was conducted across MEDLINE, EMBASE, and Cochrane databases through December 2020 for studies using nintedanib to treat patients with PPF. Data Extraction: Mortality, disease progression, and adverse event data were extracted, and meta-analyses performed when possible. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) Working Group approach was used to assess the quality of evidence. Synthesis: Two relevant studies were selected. The annual decline in forced vital capacity was less in the nintedanib arm in the overall study population (mean difference [MD], 107 ml/yr; 95% confidence interval [CI], 65.4 to 148.5 ml/yr) and in the subgroups with usual interstitial pneumonia (UIP) pattern of pulmonary fibrosis (MD, 128.2 ml/yr; 95% CI, 70.8 to 185.6 ml/yr), non-UIP patterns of pulmonary fibrosis (MD, 75.3 ml/yr; 95% CI, 15.5 to 135.0 ml/yr), fibrotic connective tissue disease-related ILD (MD, 106.2 ml/yr; 95% CI, 10.6 to 201.9 ml/yr), fibrotic idiopathic nonspecific interstitial pneumonia (MD, 141.7 ml/yr; 95% CI, 46.0 to 237.4 ml/yr), and fibrotic occupational ILD (MD, 252.8 ml/yr; 95% CI, 79.2 to 426.5 ml/yr), but not fibrotic hypersensitivity pneumonitis (MD, 72.9 ml/yr; 95% CI, -8.9 to 154.7 ml/yr), fibrotic sarcoidosis (MD, -20.5 ml/yr; 95% CI, -337.1 to 296.1 ml/yr), or unclassified fibrotic ILD (MD, 68.5 ml/yr; 95% CI, -31.3 to 168.4 ml/yr) when compared with placebo. Gastrointestinal side effects were common. Quality of evidence for the outcomes ranged from very low to moderate GRADE. Conclusions: Nintedanib use in patients with PPF is associated with a statistically significant decrease in disease progression but increase in gastrointestinal side effects regardless of the radiographic pattern of pulmonary fibrosis. However, limitations in the available evidence lead to low certainty in these effect estimates and make definitive conclusions about the differential effects by subtype of ILD difficult to determine. Primary Source of Funding: Funded by the American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax.

Transbronchial Lung Cryobiopsy in Patients with Interstitial Lung Disease: A Systematic Review.

Rationale: In 2018, a systematic review evaluating transbronchial lung cryobiopsy (TBLC) in patients with interstitial lung disease (ILD) was performed to inform American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax clinical practice guidelines on the diagnosis of idiopathic pulmonary fibrosis. Objectives: To perform a new systematic review to inform updated guidelines. Methods: Medline, Excerpta Medica Database, and the Cochrane Central Register of Controlled Trials (CCTR) were searched through June 2020. Studies that enrolled patients with ILD and reported the diagnostic yield or complication rates of TBLC were selected for inclusion. Data was extracted and then pooled across studies via meta-analysis. The quality of the evidence was appraised using the grading of recommendations, assessment, development, and evaluation approach. Results: Histopathologic diagnostic yield (number of procedures that yielded a histopathologic diagnosis divided by the total number of procedures performed) of TBLC was 80% (95% confidence interval [CI], 76-83%) in patients with ILD. TBLC was complicated by bleeding and pneumothorax in 30% (95% CI, 20-41%) and 8% (95% CI, 6-11%) of patients, respectively. Procedure-related mortality, severe bleeding, prolonged air leak, acute exacerbation, respiratory failure, and respiratory infection were rare. The quality of the evidence was very low owing to the uncontrolled study designs, lack of consecutive enrollment, and inconsistent results. Conclusions: Very low-quality evidence indicated that TBLC has a diagnostic yield of approximately 80% in patients with ILD, with manageable complications.

Idiopathic Pulmonary Fibrosis (an Update) and Progressive Pulmonary Fibrosis in Adults: An Official ATS/ERS/JRS/ALAT Clinical Practice Guideline.

Background: This American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana de Tórax guideline updates prior idiopathic pulmonary fibrosis (IPF) guidelines and addresses the progression of pulmonary fibrosis in patients with interstitial lung diseases (ILDs) other than IPF. Methods: A committee was composed of multidisciplinary experts in ILD, methodologists, and patient representatives. 1) Update of IPF: Radiological and histopathological criteria for IPF were updated by consensus. Questions about transbronchial lung cryobiopsy, genomic classifier testing, antacid medication, and antireflux surgery were informed by systematic reviews and answered with evidence-based recommendations using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. 2) Progressive pulmonary fibrosis (PPF): PPF was defined, and then radiological and physiological criteria for PPF were determined by consensus. Questions about pirfenidone and nintedanib were informed by systematic reviews and answered with evidence-based recommendations using the GRADE approach. Results:1) Update of IPF: A conditional recommendation was made to regard transbronchial lung cryobiopsy as an acceptable alternative to surgical lung biopsy in centers with appropriate expertise. No recommendation was made for or against genomic classifier testing. Conditional recommendations were made against antacid medication and antireflux surgery for the treatment of IPF. 2) PPF: PPF was defined as at least two of three criteria (worsening symptoms, radiological progression, and physiological progression) occurring within the past year with no alternative explanation in a patient with an ILD other than IPF. A conditional recommendation was made for nintedanib, and additional research into pirfenidone was recommended. Conclusions: The conditional recommendations in this guideline are intended to provide the basis for rational, informed decisions by clinicians.

Antacid Medication and Antireflux Surgery in Patients with Idiopathic Pulmonary Fibrosis: A Systematic Review and Meta-Analysis.

Rationale: Idiopathic pulmonary fibrosis (IPF) is a fibrosing interstitial pneumonia with impaired survival. Previous guidelines recommend antacid medication to improve respiratory outcomes in patients with IPF. Objectives: This systematic review was undertaken during the development of an American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax guideline. The clinical question was, "Should patients with IPF who have documented abnormal gastroesophageal reflux (GER) with or without symptoms of GER disease 1) be treated with antacid medication or 2) undergo antireflux surgery to improve respiratory outcomes?" Methods: Medline, Embase, the Cochrane Central Register of Controlled Trials, and the gray literature were searched through June 30, 2020. Studies that enrolled patients with IPF and 1) compared antacid medication to placebo or no medication or 2) compared antireflux surgery to no surgery were selected. Meta-analyses were performed when possible. Outcomes included disease progression, mortality, exacerbations, hospitalizations, lung function, respiratory symptoms, GER severity, and adverse effects/complications. Results: For antacid medication, when two studies were aggregated, there was no statistically significant effect on disease progression, defined as a 10% or more decline in FVC, more than 50-m decline in 6-minute walking distance, or death (risk ratio [RR], 0.88; 95% confidence interval [CI], 0.76-1.03). A separate study that could not be included in the meta-analysis found no statistically significant effect on disease progression when defined as a 5% or more decline in FVC or death (RR, 1.10; 95% CI, 1.00-1.21) and an increase in disease progression when defined as a 10% or more decline in FVC or death (RR, 1.28; 95% CI, 1.08-1.51). For antireflux surgery, there was also no statistically significant effect on disease progression (RR, 0.29; 95% CI, 0.06-1.26). Neither antacid medications nor antireflux surgery was associated with improvements in the other outcomes. Conclusions: There is insufficient evidence to conclude that antacid medication or antireflux surgery improves respiratory outcomes in patients with IPF, most of whom had not had abnormal GER confirmed. Well-designed and adequately powered prospective studies with objective evaluation for GER are critical to elucidate the role of antacid medication and antireflux surgery for respiratory outcomes in patients with IPF.

Use of a Genomic Classifier in Patients with Interstitial Lung Disease: A Systematic Review and Meta-Analysis.

Background: Usual interstitial pneumonia (UIP) is the histopathologic hallmark of idiopathic pulmonary fibrosis (IPF), the prototypical interstitial lung disease (ILD). Diagnosis of IPF requires that a typical UIP pattern be identified by using high-resolution chest computed tomography or lung sampling. A genomic classifier for UIP has been developed to predict histopathologic UIP by using lung samples obtained through bronchoscopy. Objective: To perform a systematic review to evaluate genomic classifier testing in the detection of histopathologic UIP to inform new American Thoracic Society, European Respiratory Society, Japanese Respiratory Society, and Asociación Latinoamericana del Tórax guidelines. Data Sources: Medline, Embase, and the Cochrane Central Register of Controlled Trials were searched through June 2020. Data Extraction: Data were extracted from studies that enrolled patients with ILD and reported the use of genomic classifier testing. Synthesis: Data were aggregated across studies via meta-analysis. The quality of the evidence was appraised by using the Grading of Recommendations, Assessment, Development, and Evaluation approach. Results: Genomic classifier testing had a sensitivity of 68% (95% confidence interval [CI], 55-73%) and a specificity of 92% (95% CI, 81-95%) in predicting the UIP pattern in ILD. Confidence in an IPF diagnosis increased from 43% to 93% in one cohort and from 59% to 89% in another cohort. Agreement levels in categorical IPF and non-IPF diagnoses measured by using a concordance coefficient were 0.75 and 0.64 in the two cohorts. The quality of evidence was moderate for test characteristics and very low for both confidence and agreement. Conclusions: Genomic classifier testing predicts histopathologic UIP in patients with ILD with a specificity of 92% and improves diagnostic confidence; however, sensitivity is only 68%, and testing is not widely available.