Inhaled Nitric Oxide in Fibrotic Lung Disease: A Randomized, Double-Blind, Placebo-Controlled Trial.

RATIONALE: Inhaled nitric oxide (iNO) has been shown to result in benefits in moderate to vigorous physical activity (MVPA) in patients with fibrotic interstitial lung disease (if-ILD) on supplemental oxygen in two independent trials. OBJECTIVE: This phase 3 randomized double-blind placebo-controlled study sought to validate the benefit of ambulatory iNO in patients with f-ILD requiring supplemental oxygen. METHODS: Patients with f-ILD on supplemental long-term oxygen were randomized in a 1:1 fashion to inhaled nitric oxide at 45 µg/kg ideal body weight/hour or placebo for 16 weeks. The primary outcome was the change from baseline to week 16 in MVPA assessed by accelerometry. Secondary outcomes included overall activity, six-minute walk distance and patient reported outcomes. MEASUREMENT AND MAIN RESULTS: 145 patients were enrolled; 75 were assigned to receive iNO and 70 to placebo. The change from baseline in MVPA at 16 weeks was -9.2 minute/day (SE 3.51) in the iNO45 group versus -3.7 (3.76) minute/day in the placebo group (difference, 5.5; P=0.265). No statistically significant differences between the two treatment arms were found for any of the secondary outcomes. A subgroup analysis of patients with intermediate or high probability of pulmonary hypertension on echocardiography did not demonstrate any benefit. The most common adverse events reported were respiratory tract infections, but the therapy was generally very well tolerated. CONCLUSIONS: There was no demonstrable benefit to iNO in patients with f-ILD on supplemental oxygen in daily physical activity assessed by actigraphy, a potential novel clinical trial endpoint. Clinical trial registration available at www. CLINICALTRIALS: gov, ID: NCT03267108.

Bexotegrast in Patients with Idiopathic Pulmonary Fibrosis: The INTEGRIS-IPF Clinical Trial.

Rationale: Idiopathic pulmonary fibrosis (IPF) is a rare and progressive disease that causes progressive cough, exertional dyspnea, impaired quality of life, and death. Objectives: Bexotegrast (PLN-74809) is an oral, once-daily, investigational drug in development for the treatment of IPF. Methods: This Phase-2a multicenter, clinical trial randomized participants with IPF to receive, orally and once daily, bexotegrast at 40 mg, 80 mg, 160 mg, or 320 mg, or placebo, with or without background IPF therapy (pirfenidone or nintedanib), in an approximately 3:1 ratio in each bexotegrast dose cohort, for at least 12 weeks. The primary endpoint was incidence of treatment-emergent adverse events (TEAEs). Exploratory efficacy endpoints included change from baseline in FVC, quantitative lung fibrosis (QLF) extent (%), and changes from baseline in fibrosis-related biomarkers. Measurements and Main Results: Bexotegrast was well tolerated, with similar rates of TEAEs in the pooled bexotegrast and placebo groups (62/89 [69.7%] and 21/31 [67.7%], respectively). Diarrhea was the most common TEAE; most participants with diarrhea also received nintedanib. Participants who were treated with bexotegrast experienced a reduction in FVC decline over 12 weeks compared with those who received placebo, with or without background therapy. A dose-dependent antifibrotic effect of bexotegrast was observed with QLF imaging, and a decrease in fibrosis-associated biomarkers was observed with bexotegrast versus placebo. Conclusions: Bexotegrast demonstrated a favorable safety and tolerability profile, up to 12 weeks for the doses studied. Exploratory analyses suggest an antifibrotic effect according to FVC, QLF imaging, and circulating levels of fibrosis biomarkers. Clinical trial registered with www.clinicaltrials.gov (NCT04396756).

Phase 2, Double-Blind, Placebo-controlled Trial of a c-Jun N-Terminal Kinase Inhibitor in Idiopathic Pulmonary Fibrosis.

Rationale: Idiopathic pulmonary fibrosis is a fatal and progressive disease with limited treatment options. Objectives: We sought to assess the efficacy and safety of CC-90001, an oral inhibitor of c-Jun N-terminal kinase 1, in patients with idiopathic pulmonary fibrosis. Methods: In a Phase 2, randomized (1:1:1), double-blind, placebo-controlled study (ClinicalTrials.gov ID: NCT03142191), patients received CC-90001 (200 or 400 mg) or placebo once daily for 24 weeks. Background antifibrotic treatment (pirfenidone) was allowed. The primary endpoint was change in the percentage of predicted FVC (ppFVC) from baseline to Week 24; secondary endpoints included safety. Measurements and Main Results: In total, 112 patients received at least one dose of study drug. The study was terminated early because of a strategic decision made by the sponsor. Ninety-one patients (81%) completed the study. The least-squares mean changes from baseline in ppFVC at Week 24 were -3.1% (placebo), -2.1% (200 mg), and -1.0% (400 mg); the differences compared with placebo were 1.1% (200 mg; 95% confidence interval: -2.1, 4.3; P = 0.50) and 2.2% (400 mg; 95% confidence interval: -1.1, 5.4; P = 0.19). Adverse event frequency was similar in patients in the combined CC-90001 arms versus placebo. The most common adverse events were nausea, diarrhea, and vomiting, which were more frequent in patients in CC-90001 arms versus placebo. Fewer patients in the CC-90001 arms than in the placebo arm experienced cough and dyspnea. Conclusions: Treatment with CC-90001 over 24 weeks led to numerical improvements in ppFVC in patients with idiopathic pulmonary fibrosis compared with placebo. CC-90001 was generally well tolerated, which was consistent with previous studies. Clinical trial registered with www.clinicaltrials.gov (NCT03142191).

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.

Visual and morphometric description of feral horse hooves from Sable Island National Park Reserve.

Objective: To visually evaluate and morphometrically describe a sample of abnormal hooves from Sable Island horses that died between 2007 and 2013. Animal: Equine. Procedure: An opportunistic sample of 356 abnormal hooves from horses inhabiting Sable Island National Park Reserve (Canada) was collected postmortem between 2007 and 2013 from 101 Sable Island horses. These hooves were assessed for abnormalities in conformation through visual and morphometric evaluation. Results: On visual and morphometric evaluation, 100% of horses (101/101) had abnormal hoof conformation when compared to a domestic horse hoof model. Specific abnormalities from visual evaluation included long heels (85%); medial, lateral, and dorsal flares (45, 78, and 46% of horses, respectively); and cracking (62%). Specific abnormalities determined from morphometry of the hooves included contracted heels (87%), hoof imbalances including mediolateral imbalance (61%), and hoof length greater than width (100%). Conclusion: Sable Island horses had various hoof abnormalities such as hoof capsule flaring; long, contracted heels; and mediolateral imbalance. These abnormalities have been observed in other feral horse populations living on soft substrates. Given the potential impact of hoof abnormalities on the welfare status of the Sable Island horses, further studies are warranted, including estimation of the prevalence of hoof abnormalities and direct observation of horse gait and behavior. Clinical relevance: The significance of the hoof abnormalities for the health of the Sable Island horses is difficult to determine but the issue highlights the importance of further study to investigate the impact on the horses' welfare.

Description visuelle et morphométrique des sabots de chevaux sauvages de la réserve de parc national de l'Île-de-Sable. Objectif: Évaluer visuellement et décrire morphométriquement un échantillon de sabots anormaux de chevaux de l'île de Sable décédés entre 2007 et 2013. Animal: Cheval. Procédure: Un échantillon opportuniste de 356 sabots anormaux provenant de chevaux habitant la réserve de parc national de l'Île-de-Sable (Canada) a été prélevé post-mortem entre 2007 et 2013 sur 101 chevaux de l'île-de-Sable. Ces sabots ont été évalués pour déceler des anomalies de conformation par une évaluation visuelle et morphométrique. Résultats: Lors de l'évaluation visuelle et morphométrique, 100 % des chevaux (101/101) présentaient une conformation de sabot anormale par rapport à un modèle de sabot de cheval domestique. Les anomalies spécifiques de l'évaluation visuelle comprenaient les talons longs (85 %); poussées médiales, latérales et dorsales (respectivement 45, 78 et 46 % des chevaux); et fissuration (62 %). Les anomalies spécifiques déterminées à partir de la morphométrie des sabots comprenaient des talons contractés (87 %), des déséquilibres des sabots, notamment un déséquilibre médiolatéral (61 %) et une longueur du sabot supérieure à la largeur (100 %). Conclusion: Les chevaux de l'île-de-Sable présentaient diverses anomalies aux sabots, telles qu'un évasement de la boîte cornée; talons longs et contractés; et déséquilibre médiolatéral. Ces anomalies ont été observées chez d'autres populations de chevaux sauvages vivant sur des substrats mous. Compte tenu de l'impact potentiel des anomalies des sabots sur le bien-être des chevaux de l'Île-de-Sable, d'autres études sont justifiées, notamment l'estimation de la prévalence des anomalies des sabots et l'observation directe de la démarche et du comportement des chevaux. Pertinence clinique: L'importance des anomalies des sabots pour la santé des chevaux de l'Île-de-Sable est difficile à déterminer, mais la question souligne l'importance d'une étude plus approfondie pour étudier l'impact sur le bien-être des chevaux.(Traduit par Dr Serge Messier).

Characteristics of patients with pulmonary arterial hypertension from an innovative, comprehensive real-world patient data repository.

Pulmonary arterial hypertension (PAH) is a rare, life-limiting disease. PAH registries provide real-world data that complement clinical trial data and inform treatment decisions. The TRIO comprehensive, integrated patient data repository (TRIO CIPDR), is an innovative US repository capturing data on contemporary patients diagnosed with pulmonary hypertension and receiving US Food and Drug Administration-approved PAH therapies. This repository uniquely combines clinical data from electronic medical records with the ability to track drug-prescription and drug-dispensing characteristics, and includes 946 adult patients with PAH (data collected January 2019 to December 2020) enrolled from nine representative US specialist tertiary care centers. Potentially eligible patients were identified based on dispensing data from specialty pharmacies. Hemodynamic and clinical data, as well as dispensing information on prescribed PAH medications, were provided by tertiary centers. At enrollment, 75% of patients were female, 67% were White, median age at PAH diagnosis was 53 years (median time from diagnosis to enrollment was 5 years), and 37% were obese. Comorbidity profiles were as expected for a PAH population, although the proportion with atrial fibrillation (34%) was higher than expected. Overall, 38% of patients had idiopathic PAH and 30% had connective tissue disease-related PAH. Among 917 patients receiving PAH-specific therapy, 40% were on monotherapy, 43% on dual therapy, and 17% on triple therapy. Longitudinal data from this repository will allow tracking of the PAH treatment journey in relation to clinical characteristics and outcomes.

Efficacy and Safety of Pirfenidone in Advanced Versus Non-Advanced Idiopathic Pulmonary Fibrosis: Post-Hoc Analysis of Six Clinical Studies.

INTRODUCTION: In the European Union (EU), the indication for the antifibrotic pirfenidone prior to April 2023 did not include patients with advanced idiopathic pulmonary fibrosis (IPF). This analysis compared the efficacy and safety of pirfenidone in advanced IPF versus non-advanced IPF. METHODS: Data were included from the following studies of pirfenidone: ASCEND (NCT01366209); CAPACITY (004 [NCT00287716] and 006 [NCT00287729]); RECAP (NCT00662038; advanced IPF defined as percent predicted forced vital capacity [%FVC] < 50% and/or percent predicted carbon monoxide diffusing capacity [%DLco] < 35% at baseline); PASSPORT (NCT02699879; advanced IPF defined as baseline %FVC < 50%); and SP-IPF (NCT02951429; patients with advanced IPF [defined as %DLco ≤ 40% at screening] at risk of group 3 pulmonary hypertension). RESULTS: In the pooled ASCEND/CAPACITY studies, the annual mean rate of FVC decline from baseline to Week 52 was significantly lower for pirfenidone versus placebo in advanced (p = 0.0035) and non-advanced IPF (p = 0.0001). Rate of all-cause mortality over 52 weeks was numerically lower for pirfenidone versus placebo in advanced and non-advanced IPF. In RECAP, the mean annual rate of FVC decline from baseline to Week 180 of pirfenidone treatment was similar in patients with advanced (- 141.5 mL) and non-advanced IPF (- 153.5 mL). In SP-IPF, the mean annual rate of FVC decline and rate of all-cause mortality from baseline to Week 52 in patients treated with placebo + pirfenidone were - 93.0 mL and 20.2%, respectively. No new safety signals were identified, and the safety profile of pirfenidone in patients with advanced IPF was generally consistent with that of non-advanced IPF. CONCLUSIONS: These results highlight the benefit of pirfenidone treatment in patients with advanced and non-advanced IPF. As such, the indication for pirfenidone in the EU has now been updated to include the treatment of adult patients with advanced IPF. TRIAL REGISTRATIONS: ASCEND (NCT01366209), CAPACITY 004 (NCT00287716), CAPACITY 006 (NCT00287729), RECAP (NCT00662038), PASSPORT (NCT02699879), and SP-IPF (NCT02951429).

Low Gut Microbial Diversity Augments Estrogen-Driven Pulmonary Fibrosis in Female-Predominant Interstitial Lung Disease.

Although profibrotic cytokines, such as IL-17A and TGF-ß1, have been implicated in the pathogenesis of interstitial lung disease (ILD), the interactions between gut dysbiosis, gonadotrophic hormones and molecular mediators of profibrotic cytokine expression, such as the phosphorylation of STAT3, have not been defined. Here, through chromatin immunoprecipitation sequencing (ChIP-seq) analysis of primary human CD4+ T cells, we show that regions within the STAT3 locus are significantly enriched for binding by the transcription factor estrogen receptor alpha (ERa). Using the murine model of bleomycin-induced pulmonary fibrosis, we found significantly increased regulatory T cells compared to Th17 cells in the female lung. The genetic absence of ESR1 or ovariectomy in mice significantly increased pSTAT3 and IL-17A expression in pulmonary CD4+ T cells, which was reduced after the repletion of female hormones. Remarkably, there was no significant reduction in lung fibrosis under either condition, suggesting that factors outside of ovarian hormones also contribute. An assessment of lung fibrosis among menstruating females in different rearing environments revealed that environments favoring gut dysbiosis augment fibrosis. Furthermore, hormone repletion following ovariectomy further augmented lung fibrosis, suggesting pathologic interactions between gonadal hormones and gut microbiota in relation to lung fibrosis severity. An analysis of female sarcoidosis patients revealed a significant reduction in pSTAT3 and IL-17A levels and a concomitant increase in TGF-ß1 levels in CD4+ T cells compared to male sarcoidosis patients. These studies reveal that estrogen is profibrotic in females and that gut dysbiosis in menstruating females augments lung fibrosis severity, supporting a critical interaction between gonadal hormones and gut flora in lung fibrosis pathogenesis.

Low Gut Microbial Diversity Augments Estrogen-driven Pulmonary Fibrosis in Female-Predominant Interstitial Lung Disease.

Although profibrotic cytokines such as IL-17A and TGF-ß1 have been implicated in interstitial lung disease (ILD) pathogenesis, interactions between gut dysbiosis, gonadotrophic hormones and molecular mediators of profibrotic cytokine expression, such as phosphorylation of STAT3, have not been defined. Here we show by chromatin immunoprecipitation sequencing (ChIP-seq) analysis of primary human CD4+ T cells that regions within the STAT3 locus are significantly enriched for binding by the transcription factor estrogen receptor alpha (ERa). Using the murine model of bleomycin-induced pulmonary fibrosis, we found significantly increased regulatory T cells compared to Th17 cells in the female lung. Genetic absence of ESR1 or ovariectomy in mice significantly increased pSTAT3 and IL-17A expression in pulmonary CD4+ T cells, which was reduced after repletion of female hormones. Remarkably, there was no significant reduction in lung fibrosis under either condition, suggesting that factors outside of ovarian hormones also contribute. Assessment of lung fibrosis among menstruating females in different rearing environments revealed that environments favoring gut dysbiosis augment fibrosis. Furthermore, hormone repletion following ovariectomy further augmented lung fibrosis, suggesting pathologic interactions between gonadal hormones and gut microbiota on lung fibrosis severity. Analysis in female sarcoidosis patients revealed a significant reduction in pSTAT3 and IL-17A levels and a concomitant increase in TGF-ß1 levels in CD4+ T cells, compared to male sarcoidosis patients. These studies reveal that estrogen is profibrotic in females and that gut dysbiosis in menstruating females augments lung fibrosis severity, supporting a critical interaction between gonadal hormones and gut flora in lung fibrosis pathogenesis.

PCSK6 and Survival in Idiopathic Pulmonary Fibrosis.

Rationale: Idiopathic pulmonary fibrosis (IPF) is a devastating disease characterized by limited treatment options and high mortality. A better understanding of the molecular drivers of IPF progression is needed. Objectives: To identify and validate molecular determinants of IPF survival. Methods: A staged genome-wide association study was performed using paired genomic and survival data. Stage I cases were drawn from centers across the United States and Europe and stage II cases from Vanderbilt University. Cox proportional hazards regression was used to identify gene variants associated with differential transplantation-free survival (TFS). Stage I variants with nominal significance (P < 5 × 10-5) were advanced for stage II testing and meta-analyzed to identify those reaching genome-wide significance (P < 5 × 10-8). Downstream analyses were performed for genes and proteins associated with variants reaching genome-wide significance. Measurements and Main Results: After quality controls, 1,481 stage I cases and 397 stage II cases were included in the analysis. After filtering, 9,075,629 variants were tested in stage I, with 158 meeting advancement criteria. Four variants associated with TFS with consistent effect direction were identified in stage II, including one in an intron of PCSK6 (proprotein convertase subtilisin/kexin type 6) reaching genome-wide significance (hazard ratio, 4.11 [95% confidence interval, 2.54-6.67]; P = 9.45 × 10-9). PCSK6 protein was highly expressed in IPF lung parenchyma. PCSK6 lung staining intensity, peripheral blood gene expression, and plasma concentration were associated with reduced TFS. Conclusions: We identified four novel variants associated with IPF survival, including one in PCSK6 that reached genome-wide significance. Downstream analyses suggested that PCSK6 protein plays a potentially important role in IPF progression.

The Association between Exposures and Disease Characteristics in Familial Pulmonary Fibrosis.

Rationale: Heterogeneous characteristics are observed in familial pulmonary fibrosis (FPF), suggesting that nongenetic factors contribute to disease manifestations. Objectives: To determine the relationship between environmental exposures and disease characteristics of FPF, including the morphological characteristics on chest computed tomography (CT) scan, and timing of FPF symptom onset, lung transplantation, or death. Methods: Subjects with FPF with an exposure questionnaire and chest CT were selected from a prospective cohort at Vanderbilt. Disease characteristics were defined by lung parenchymal findings on chest CT associated with fibrotic hypersensitivity pneumonitis (fHP) or usual interstitial pneumonia (UIP) and by time from birth to symptom onset or a composite of lung transplantation or death. After assessing the potential for confounding by sex or smoking, adjusted logistic or Cox proportional hazards regression models identified exposures associated with fHP or UIP CT findings. Findings were validated in a cohort of patients with sporadic pulmonary fibrosis enrolled in the LTRC (Lung Tissue Research Consortium) study. Results: Among 159 subjects with FPF, 98 (61.6%) were males and 96 (60.4%) were ever-smokers. Males were less likely to have CT features of fHP, including mosaic attenuation (FPF: adjusted [for sex and smoking] odds ratio [aOR], 0.27; 95% confidence interval [CI], 0.09-0.76; P = 0.01; LTRC: aOR, 0.35; 95% CI, 0.21-0.61; P = 0.0002). Organic exposures, however, were not consistently associated with fHP features in either cohort. Smoking was a risk factor for honeycombing in both cohorts (FPF: aOR, 2.19; 95% CI, 1.12-4.28; P = 0.02; LTRC: aOR, 1.69; 95% CI, 1.22-2.33; P = 0.002). Rock dust exposure may also be associated with honeycombing, although the association was not statistically-significant when accounting for sex and smoking (FPF: aOR, 2.27; 95% CI, 0.997-5.15; P = 0.051; LTRC: aOR, 1.51; 95% CI, 0.97-2.33; P = 0.07). In the FPF cohort, ever-smokers experienced a shorter transplant-free survival (adjusted hazard ratio, 1.64; 95% CI, 1.07-2.52; P = 0.02), whereas sex was not associated with differential survival (male adjusted hazard ratio, 0.75; 95% CI, 0.50-1.14; P = 0.18). Conclusions: In FPF, smoking contributes to shortened transplant-free survival and development of honeycombing, a finding that is also likely applicable to sporadic pulmonary fibrosis. Females are more likely to manifest CT features of fHP (mosaic attenuation), a finding that was incompletely explained by sex differences in exposures. These findings may have implications for pulmonary fibrosis classification and management.

Study design and rationale for the TETON phase 3, randomised, controlled clinical trials of inhaled treprostinil in the treatment of idiopathic pulmonary fibrosis.

INTRODUCTION: Idiopathic pulmonary fibrosis (IPF) greatly impacts quality of life and eventually leads to premature death from respiratory failure. Inhaled treprostinil was associated with improvements in forced vital capacity (FVC) and reduced exacerbations of underlying lung disease in post hoc analyses from a phase 3 study in patients with precapillary pulmonary hypertension due to interstitial lung disease. These results, combined with preclinical evidence of treprostinil's antifibrotic activity, support its investigation in the treatment of IPF. METHODS AND ANALYSIS: The TETON programme consists of two replicate, 52-week, randomised, double-blind placebo-controlled, phase 3 studies, each enrolling 396 subjects (NCT04708782, NCT05255991). Eligible subjects must have a diagnosis of IPF confirmed by central imaging review, along with an FVC ≥45%. Stable background use of pirfenidone or nintedanib is allowed. The primary endpoint is change in absolute FVC at week 52. Secondary endpoints include time to clinical worsening (first event of death, respiratory hospitalisation or ≥10% decline in % predicted FVC), time to first acute exacerbation of IPF, overall survival, change in % predicted FVC and change in the King's Brief Interstitial Lung Disease Questionnaire at week 52. Safety parameters include adverse events, hospitalisations, oxygenation and laboratory parameters. Patients who complete week 52 will be eligible to enter an open-label extension study. ETHICS AND DISSEMINATION: Studies will be conducted in accordance with the International Conference on Harmonisation Guideline for Good Clinical Practice, Declaration of Helsinki principles, and local regulatory, ethical and legal requirements. Results will be published in a peer-reviewed publication.

The Antifibrotic Effects of Inhaled Treprostinil: An Emerging Option for ILD.

Interstitial lung diseases (ILD) encompasses a heterogeneous group of parenchymal lung diseases characterized by variable amounts of inflammation and fibrosis. The targeting of fibroblasts and myofibroblasts with antifibrotic treatments is a potential therapeutic target for these potentially fatal diseases. Treprostinil is unique among the prostacyclin mimetics in that it has distinct actions at additional prostaglandin receptors. Preclinical and clinical evidence suggests that treprostinil has antifibrotic effects through the activation of the prostaglandin E receptor 2 (EP2), the prostaglandin D receptor 1 (DP1), and peroxisome proliferator-activated receptors (PPAR). In vivo studies of EP2 and the DP1 have found that administration of treprostinil resulted in a reduction in cell proliferation, reduced collagen secretion and synthesis, and reduced lung inflammation and fibrosis. In vitro and in vivo studies of PPARß and PPARγ demonstrated that treprostinil inhibited fibroblast proliferation in a dose-dependent manner. Clinical data from a post hoc analysis of the INCREASE trial found that inhaled treprostinil improved forced vital capacity in the overall population as well as in idiopathic interstitial pneumonia and idiopathic pulmonary fibrosis subgroups. These preclinical and clinical findings suggest a dual benefit of treprostinil through the amelioration of both lung fibrosis and pulmonary hypertension.

A Phase IIb Randomized Clinical Study of an Anti-αvß6 Monoclonal Antibody in Idiopathic Pulmonary Fibrosis.

Rationale: Treatment options for idiopathic pulmonary fibrosis (IPF) are limited. Objectives: To evaluate the efficacy and safety of BG00011, an anti-αvß6 IgG1 monoclonal antibody, in the treatment of patients with IPF. Methods: In a phase IIb randomized, double-blind, placebo-controlled trial, patients with IPF (FVC ⩾50% predicted, on or off background therapy) were randomized 1:1 to once-weekly subcutaneous BG00011 56 mg or placebo. The primary endpoint was FVC change from baseline at Week 52. Because of early trial termination (imbalance in adverse events and lack of clinical benefit), endpoints were evaluated at Week 26 as an exploratory analysis. Measurements and Main Results: One hundred six patients were randomized and received at least one dose of BG00011 (n = 54) or placebo (n = 52). At Week 26, there was no significant difference in FVC change from baseline between patients who received BG00011 (n = 20) or placebo (n = 23), least squares mean (SE) -0.097 L (0.0600) versus -0.056 L (0.0593), respectively (P = 0.268). However, after Week 26, patients in the BG00011 group showed a worsening trend. Eight (44.4%) of 18 who received BG00011 and 4 (18.2%) of 22 who received placebo showed worsening of fibrosis on high-resolution computed tomography at the end of treatment. IPF exacerbation/or progression was reported in 13 patients (all in the BG00011 group). Serious adverse events occurred more frequently in BG00011 patients, including four deaths. Conclusions: The results do not support the continued clinical development of BG00011. Further research is warranted to identify new treatment strategies that modify inflammatory and fibrotic pathways in IPF. Clinical trial registered with www.clinicaltrials.gov (NCT03573505).

Multidisciplinary clinical guidance on trastuzumab deruxtecan (T-DXd)-related interstitial lung disease/pneumonitis-Focus on proactive monitoring, diagnosis, and management.

Trastuzumab deruxtecan (T-DXd; DS-8201) is an antibody-drug conjugate targeting human epidermal growth factor receptor 2. Interstitial lung disease (ILD)/pneumonitis is an adverse event associated with T-DXd; in most cases, it is low grade (grade ≤ 2) and can be treated effectively but may develop to be fatal in some instances. It is important to increase patient and provider understanding of T-DXd-related ILD/pneumonitis to improve patient outcomes. Drug-related ILD/pneumonitis is a diagnosis of exclusion; other possible causes of lung injury/imaging findings must be ruled out for an accurate diagnosis. Symptoms can be nonspecific, and identifying early symptoms is challenging; therefore, diagnosis is often delayed. We reviewed characteristics of patients who developed T-DXd-related ILD/pneumonitis and its patterns, produced multidisciplinary guidelines on diagnosis and management, and described areas for future investigation. Ongoing studies are collecting data on T-DXd-related ILD/pneumonitis to further our understanding of its clinical patterns and mechanisms. SEARCH STRATEGY AND SELECTION CRITERIA: References were identified based on the guidelines used by the authors in treating interstitial lung disease and pneumonitis. Searches of the authors' own files were also completed. A search of PubMed with the search terms (trastuzumab deruxtecan) AND (interstitial lung disease) AND (guidelines) was conducted on November 1, 2021, with no restrictions based on publication date, and the two articles yielded by the search were included.

Screening Strategies for Pulmonary Hypertension in Patients With Interstitial Lung Disease: A Multidisciplinary Delphi Study.

BACKGROUND: Pulmonary hypertension (PH) is a common complication of interstitial lung disease (ILD) and is associated with worse outcomes and increased mortality. Evaluation of PH is recommended in lung transplant candidates, but there are currently no standardized screening approaches. Trials have identified therapies that are effective in this setting, providing another rationale to routinely screen patients with ILD for PH. RESEARCH QUESTION: What screening strategies for identifying PH in patients with ILD are supported by expert consensus? STUDY DESIGN AND METHODS: The study convened a panel of 16 pulmonologists with expertise in PH and ILD, and used a modified Delphi consensus process with three surveys to identify PH screening strategies. Survey 1 consisted primarily of open-ended questions. Surveys 2 and 3 were developed from responses to survey 1 and contained statements about PH screening that panelists rated from -5 (strongly disagree) to 5 (strongly agree). RESULTS: Panelists reached consensus on several triggers for suspicion of PH including the following: symptoms, clinical signs, findings on chest CT scan or other imaging, abnormalities in pulse oximetry, elevations in brain natriuretic peptide (BNP) or N-terminal pro-brain natriuretic peptide (NT-proBNP), and unexplained worsening in pulmonary function tests or 6-min walk distance. Echocardiography and BNP/NT-proBNP were identified as screening tools for PH. Right heart catheterization was deemed essential for confirming PH. INTERPRETATION: Many patients with ILD may benefit from early evaluation of PH now that an approved therapy is available. Protocols to evaluate patients with ILD often overlap with evaluations for pulmonary hypertension-interstitial lung disease and can be used to assess the risk of PH. Because standardized approaches are lacking, this consensus statement is intended to aid physicians in the identification of patients with ILD and possible PH, and provide guidance for timely right heart catheterization.

Effects of nintedanib by inclusion criteria for progression of interstitial lung disease.

BACKGROUND: The INBUILD trial investigated nintedanib versus placebo in patients with progressive fibrosing interstitial lung diseases (ILDs). We investigated the decline in forced vital capacity (FVC) in subgroups based on the inclusion criteria for ILD progression. METHODS: Subjects had a fibrosing ILD other than idiopathic pulmonary fibrosis and met the following criteria for ILD progression within the 24 months before screening despite management deemed appropriate in clinical practice: Group A, relative decline in FVC ≥10% predicted; Group B, relative decline in FVC ≥5-<10% predicted with worsened respiratory symptoms and/or increased extent of fibrosis on high-resolution computed tomography (HRCT); Group C, worsened respiratory symptoms and increased extent of fibrosis on HRCT only. RESULTS: In the placebo group, the rates of FVC decline over 52 weeks in Groups A, B and C, respectively, were -241.9, -133.1 and -115.3 mL per year in the overall population (p=0.0002 for subgroup-by-time interaction) and -288.9, -156.2 and -100.1 mL per year among subjects with a usual interstitial pneumonia (UIP)-like fibrotic pattern on HRCT (p=0.0005 for subgroup-by-time interaction). Nintedanib had a greater absolute effect on reducing the rate of FVC decline in Group A than in Group B or C. However, the relative effect of nintedanib versus placebo was consistent across the subgroups (p>0.05 for heterogeneity). CONCLUSIONS: The inclusion criteria used in the INBUILD trial, based on FVC decline or worsening of symptoms and extent of fibrosis on HRCT, were effective at identifying patients with progressive fibrosing ILDs. Nintedanib reduced the rate of decline in FVC across the subgroups based on the inclusion criteria related to ILD progression.

A Phase-2 Exploratory Randomized Controlled Trial of INOpulse in Patients with Fibrotic Interstitial Lung Disease Requiring Oxygen.

Rationale: Patients with fibrotic interstitial lung disease often progress to the point of requiring supplemental oxygen. This is invariably accompanied by an impaired quality of life and limitations on activities of daily living. Objectives: This study aimed to assess the improvement in physical activity in patients with interstitial lung disease requiring supplemental oxygen treated with pulsed inhaled nitric oxide via INOpulse (Bellerophon Therapeutics). In addition, it sought to explore the safety and clinical benefits of INOpulse on multiple patient-reported outcomes. Methods: Ambulatory patients with fibrotic lung disease on supplemental oxygen were randomized in a 2:1 ratio to inhaled nitric oxide at 45 µg/kg ideal body weight/h (iNO45) or placebo for 4 months (3 months after baseline) of blinded treatment. The study assessed multiple exploratory efficacy endpoints, including moderate to vigorous physical activity as measured by actigraphy and patient-reported outcomes using the University of California San Diego shortness of breath questionnaire and the St. George's Respiratory Questionnaire (SGRQ). Results: A total of 44 patients (30 iNO45 and 14 placebo) were enrolled. A placebo-corrected clinical benefit of 12.3 min/d increase in MVPA was observed in the iNO45 group. Clinically meaningful beneficial trends were observed for the University of California San Diego shortness of breath questionnaire (6.05 points) and the SGRQ total (3.75) scores, as well as the SGRQ activity (5.84), and SGRQ impact (6.30) domains. Conclusions: INOpulse was well tolerated and associated with maintenance of physical activity and improved symptomatology in patients with interstitial lung disease who require supplemental oxygen. Further validation of this beneficial effect warrants further study in a phase-3 trial that is currently underway.