Pursuing Clinical Predictors and Biomarkers for Progression in ILD: Analysis of the Pulmonary Fibrosis Foundation (PFF) Registry.

INTRODUCTION: Pulmonary fibrosis is a characteristic of various interstitial lung diseases (ILDs) with differing etiologies. Clinical trials in progressive pulmonary fibrosis (PPF) enroll patients based on previously described clinical criteria for past progression, which include a clinical practice guideline for PPF classification and inclusion criteria from the INBUILD trial. In this study, we compared the ability of past FVC (forced vital capacity) progression and baseline biomarker levels to predict future progression in a cohort of patients from the PFF Patient Registry. METHODS: Biomarkers previously associated with pathobiology and/or progression in pulmonary fibrosis were selected to reflect cellular senescence (telomere length), pulmonary epithelium (SP-D, RAGE), myeloid activation (CXCL13, YKL40, CCL18, OPN) and fibroblast activation (POSTN, COMP, PROC3). RESULTS: PFF or INBUILD-like clinical criteria was used to separate patients into past progressor and non-past progressor groups, and neither clinical criterion appeared to enrich for patients with greater future lung function decline. All baseline biomarkers measured were differentially expressed in patient groups compared to healthy controls. Baseline levels of SP-D and POSTN showed the highest correlations with FVC slope over one year, though correlations were low. CONCLUSIONS: Our findings provide further evidence that prior decline in lung function may not predict future disease progression for ILD patients, and elevate the need for molecular definitions of a progressive phenotype. Across ILD subtypes, certain shared pathobiologies may be present based on the molecular profile of certain biomarker groups observed. In particular, SP-D may be a common marker of pulmonary injury and future lung function decline across ILDs.

Bioactive lipid lysophosphatidic acid species are associated with disease progression in idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a progressive disease with significant mortality. Prognostic biomarkers to identify rapid progressors are urgently needed to improve patient management. Since the lysophosphatidic acid (LPA) pathway has been implicated in lung fibrosis in preclinical models and identified as a potential therapeutic target, we aimed to investigate if bioactive lipid LPA species could be prognostic biomarkers that predict IPF disease progression. LPAs and lipidomics were measured in baseline placebo plasma of a randomized IPF-controlled trial. The association of lipids with disease progression indices were assessed using statistical models. Compared to healthy, IPF patients had significantly higher levels of five LPAs (LPA16:0, 16:1, 18:1, 18:2, 20:4) and reduced levels of two triglycerides species (TAG48:4-FA12:0, -FA18:2) (false discovery rate < 0.05, fold change > 2). Patients with higher levels of LPAs had greater declines in diffusion capacity of carbon monoxide over 52 weeks (P < 0.01); additionally, LPA20:4-high (≥median) patients had earlier time to exacerbation compared to LPA20:4-low (

Biomarkers of fibrosis, inflammation, and extracellular matrix in the phase 3 trial of tocilizumab in systemic sclerosis.

Drug development for systemic sclerosis (SSc) benefits from understanding the relationship between disease and circulating biomarkers to enable activities such as patient stratification and evaluation of therapeutic response. We measured biomarkers in serum from SSc patients from a phase 3 trial of tocilizumab (focuSSced) and compared baseline levels with healthy controls (HCs). Several baseline biomarkers appeared elevated in SSc patients compared to HCs, suggesting activation of epithelial damage, inflammation, fibrosis, and extracellular matrix (ECM) remodeling. Baseline correlations among both periostin/COMP and ECM biomarker subsets implicated their participation in fibroblast activation. Tocilizumab treatment modulated serum biomarkers of macrophage activation, inflammation, and ECM turnover, including collagen formation and degradation neoepitopes. Baseline CRP, periostin, and SP-D showed prognostic trends for worsening lung function, and IL-6, COMP, periostin, and Pro-C3 showed prognostic trends for worsening skin thickness. These prognostic results warrant confirmation in additional patient cohorts to verify their utility.

Local Pentraxin-2 Deficit Is a Feature of Intestinal Fibrosis in Crohn's Disease.

BACKGROUND: Pentraxin-2 (PTX-2) is a homo-pentameric plasma protein showing evidence of antifibrotic activity in Phase 2 clinical trials in idiopathic pulmonary fibrosis (IPF). Whether PTX-2 plays a role in other fibrotic diseases, including intestinal fibrosis which commonly occurs in inflammatory bowel disease (IBD), remains unknown. AIMS: This study aimed to qualitatively and quantitatively assess PTX-2 expression in fibrostenotic Crohn's disease (FCD) and determine whether expression is correlated with postsurgical restenosis. METHODS: Immunohistochemistry was performed in histologic sections of small bowel resected from patients with fibrostenotic Crohn's disease (FCD), comparing strictured segments with adjacent surgical margins from the same patient. Ileal resections from patients without inflammatory bowel disease were examined as controls. RESULTS: PTX-2 signal was analyzed in 18 patients with FCD and 15 patients without IBD and localized predominantly to submucosal vasculature, including arterial subendothelium and internal elastic lamina, and perivascular connective tissue. PTX-2 signal in the surgical margins from patients with FCD strictures (where tissue architecture was normal) was consistently lower than non-IBD samples. Fibrostenotic regions showed increased PTX-2 signal relative to surgical margins from the same patient in 14/15 paired samples. Submucosal/mural PTX-2 signal in fibrostenotic tissue was lower in patients who subsequently experienced re-stenosis (P = 0.015). CONCLUSIONS: This exploratory study is the first analysis of PTX-2 within the intestine, and demonstrates that PTX-2 signal is reduced in the architecturally normal bowel of patients with FCD. Lower submucosal PTX-2 levels in patients with re-stenosis raises the possibility of a protective role of PTX-2 in intestinal fibrosis.

Phase 2 trial to assess lebrikizumab in patients with idiopathic pulmonary fibrosis.

This phase 2, randomised, double-blind, placebo-controlled trial evaluated the efficacy and safety of lebrikizumab, an interleukin (IL)-13 monoclonal antibody, alone or with background pirfenidone therapy, in patients with idiopathic pulmonary fibrosis (IPF).Patients with IPF aged ≥40 years with forced vital capacity (FVC) of 40%-100% predicted and diffusing capacity for carbon monoxide of 25%-90% predicted and who were treatment-naïve (cohort A) or receiving pirfenidone (2403 mg·day-1; cohort B) were randomised 1:1 to receive lebrikizumab 250 mg or placebo subcutaneously every 4 weeks. The primary endpoint was annualised rate of FVC % predicted decline over 52 weeks.In cohort A, 154 patients were randomised to receive lebrikizumab (n=78) or placebo (n=76). In cohort B, 351 patients receiving pirfenidone were randomised to receive lebrikizumab (n=174) or placebo (n=177). Baseline demographics were balanced across treatment arms in both cohorts. The primary endpoint (annualised rate of FVC % predicted decline) was not met in cohort A (lebrikizumab versus placebo, -5.2% versus -6.2%; p=0.456) or cohort B (lebrikizumab versus placebo, -5.5% versus -6.0%; p=0.557). In cohort B, a non-statistically significant imbalance in mortality favouring combination therapy was observed (hazard ratio 0.42 (95% CI 0.17-1.04)). Pharmacodynamic biomarkers indicated lebrikizumab activity. The safety profile was consistent with that in previous studies of lebrikizumab and pirfenidone as monotherapies.Lebrikizumab alone or with pirfenidone was not associated with reduced FVC % predicted decline over 52 weeks despite evidence of pharmacodynamic activity. Lebrikizumab was well tolerated with a favourable safety profile. These findings suggest that blocking IL-13 may not be sufficient to achieve a lung function benefit in patients with IPF.

RAGE and TLR4 differentially regulate airway hyperresponsiveness: Implications for COPD.

BACKGROUND: The receptor for advanced glycation end products (RAGE) and Toll-like receptor 4 (TLR4) is implicated in COPD. Although these receptors share common ligands and signalling pathways, it is not known whether they act in concert to drive pathological processes in COPD. We examined the impact of RAGE and/or TLR4 gene deficiency in a mouse model of COPD and also determined whether expression of these receptors correlates with airway neutrophilia and airway hyperresponsiveness (AHR) in COPD patients. METHODS: We measured airway inflammation and AHR in wild-type, RAGE-/- , TLR4-/- and TLR4-/- RAGE-/- mice following acute exposure to cigarette smoke (CS). We also examined the impact of smoking status on AGER (encodes RAGE) and TLR4 bronchial gene expression in patients with and without COPD. Finally, we determined whether expression of these receptors correlates with airway neutrophilia and AHR in COPD patients. RESULTS: RAGE-/- mice were protected against CS-induced neutrophilia and AHR. In contrast, TLR4-/- mice were not protected against CS-induced neutrophilia and had more severe CS-induced AHR. TLR4-/- RAGE-/- mice were not protected against CS-induced neutrophilia but were partially protected against CS-induced mediator release and AHR. Current smoking was associated with significantly lower AGER and TLR4 expression irrespective of COPD status, possibly reflecting negative feedback regulation. However, consistent with preclinical findings, AGER expression correlated with higher sputum neutrophil counts and more severe AHR in COPD patients. TLR4 expression did not correlate with neutrophilic inflammation or AHR. CONCLUSIONS: Inhibition of RAGE but not TLR4 signalling may protect against airway neutrophilia and AHR in COPD.

Genome-Wide Association Study of Susceptibility to Idiopathic Pulmonary Fibrosis.

Rationale: Idiopathic pulmonary fibrosis (IPF) is a complex lung disease characterized by scarring of the lung that is believed to result from an atypical response to injury of the epithelium. Genome-wide association studies have reported signals of association implicating multiple pathways including host defense, telomere maintenance, signaling, and cell-cell adhesion.Objectives: To improve our understanding of factors that increase IPF susceptibility by identifying previously unreported genetic associations.Methods: We conducted genome-wide analyses across three independent studies and meta-analyzed these results to generate the largest genome-wide association study of IPF to date (2,668 IPF cases and 8,591 controls). We performed replication in two independent studies (1,456 IPF cases and 11,874 controls) and functional analyses (including statistical fine-mapping, investigations into gene expression, and testing for enrichment of IPF susceptibility signals in regulatory regions) to determine putatively causal genes. Polygenic risk scores were used to assess the collective effect of variants not reported as associated with IPF.Measurements and Main Results: We identified and replicated three new genome-wide significant (P < 5 × 10-8) signals of association with IPF susceptibility (associated with altered gene expression of KIF15, MAD1L1, and DEPTOR) and confirmed associations at 11 previously reported loci. Polygenic risk score analyses showed that the combined effect of many thousands of as yet unreported IPF susceptibility variants contribute to IPF susceptibility.Conclusions: The observation that decreased DEPTOR expression associates with increased susceptibility to IPF supports recent studies demonstrating the importance of mTOR signaling in lung fibrosis. New signals of association implicating KIF15 and MAD1L1 suggest a possible role of mitotic spindle-assembly genes in IPF susceptibility.

Lysophosphatidic acid species are associated with exacerbation in chronic obstructive pulmonary disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) exacerbations are heterogenous and profoundly impact the disease trajectory. Bioactive lipid lysophosphatidic acid (LPA) has been implicated in airway inflammation but the significance of LPA in COPD exacerbation is not known. The aim of the study was to investigate the utility of serum LPA species (LPA16:0, 18:0, 18:1, 18:2, 20:4) as biomarkers of COPD exacerbation. PATIENTS AND METHODS: LPA species were measured in the baseline placebo sera of a COPD randomized controlled trial. Tertile levels of each LPA were used to assign patients into biomarker high, medium, and low subgroups. Exacerbation rate and risk were compared among the LPA subgroups. RESULTS: The levels of LPA species were intercorrelated (rho 0.29-0.91). Patients with low and medium levels of LPA (LPA16:0, 20:4) had significantly higher exacerbation rate compared to the respective LPA-high patients [estimated rate per patient per year (95% CI)]: LPA16:0-low = 1.2 (0.8-1.9) (p = 0.019), LPA16:0-medium = 1.3 (0.8-2.0) (p = 0.013), LPA16:0-high = 0.5 (0.2-0.9); LPA20:4-low = 1.4 (0.9-2.1) (p = 0.0033), LPA20:4-medium = 1.2 (0.8-1.8) (p = 0.0089), LPA20:4-high = 0.4 (0.2-0.8). These patients also had earlier time to first exacerbation (hazard ratio (95% CI): LPA16:0-low = 2.6 (1.1-6.0) (p = 0.028), LPA16:0-medium = 2.7 (1.2-6.3) (p = 0.020); LPA20.4-low = 2.8 (1.2-6.6) (p = 0.017), LPA20:4-medium = 2.7 (1.2-6.4) (p = 0.021). Accordingly, these patients had a significant increased exacerbation risk compared to the respective LPA-high subgroups [odd ratio (95% CI)]: LPA16:0-low = 3.1 (1.1-8.8) (p = 0.030), LPA16:0-medium = 3.0 (1.1-8.3) (p = 0.031); LPA20:4-low = 3.8 (1.3-10.9) (p = 0.012), LPA20:4-medium = 3.3 (1.2-9.5) (p = 0.025). For the other LPA species (LPA18:0, 18:1, 18:2), the results were mixed; patients with low and medium levels of LPA18:0 and 18:2 had increased exacerbation rate, but only LPA18:0-low patients had significant increase in exacerbation risk and earlier time to first exacerbation compared to the LPA18:0-high subgroup. CONCLUSIONS: The study provided evidence of association between systemic LPA levels and exacerbation in COPD. Patients with low and medium levels of specific LPA species (LPA16:0, 20:4) had increased exacerbation rate, risk, and earlier time to first exacerbation. These non-invasive biomarkers may aid in identifying high risk patients with dysregulated LPA pathway to inform risk management and drug development.

Genome-wide SNP-sex interaction analysis of susceptibility to idiopathic pulmonary fibrosis.

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic lung condition that is more prevalent in males than females. The reasons for this are not fully understood, with differing environmental exposures due to historically sex-biased occupations, or diagnostic bias, being possible explanations. To date, over 20 independent genetic variants have been identified to be associated with IPF susceptibility, but these have been discovered when combining males and females. Our aim was to test for the presence of sex-specific associations with IPF susceptibility and assess whether there is a need to consider sex-specific effects when evaluating genetic risk in clinical prediction models for IPF. Methods: We performed genome-wide single nucleotide polymorphism (SNP)-by-sex interaction studies of IPF risk in six independent IPF case-control studies and combined them using inverse-variance weighted fixed effect meta-analysis. In total, 4,561 cases (1,280 females and 2,281 males) and 23,500 controls (8,360 females and 14,528 males) of European genetic ancestry were analysed. We used polygenic risk scores (PRS) to assess differences in genetic risk prediction between males and females. Findings: Three independent genetic association signals were identified. All showed a consistent direction of effect across all individual IPF studies and an opposite direction of effect in IPF susceptibility between females and males. None had been previously identified in IPF susceptibility genome-wide association studies (GWAS). The predictive accuracy of the PRSs were similar between males and females, regardless of whether using combined or sex-specific GWAS results. Interpretation: We prioritised three genetic variants whose effect on IPF risk may be modified by sex, however these require further study. We found no evidence that the predictive accuracy of common SNP-based PRSs varies significantly between males and females.

Association study of human leukocyte antigen variants and idiopathic pulmonary fibrosis.

Introduction: Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial pneumonia marked by progressive lung fibrosis and a poor prognosis. Recent studies have highlighted the potential role of infection in the pathogenesis of IPF, and a prior association of the HLA-DQB1 gene with idiopathic fibrotic interstitial pneumonia (including IPF) has been reported. Owing to the important role that the human leukocyte antigen (HLA) region plays in the immune response, here we evaluated if HLA genetic variation was associated specifically with IPF risk. Methods: We performed a meta-analysis of associations of the HLA region with IPF risk in individuals of European ancestry from seven independent case-control studies of IPF (comprising 5159 cases and 27 459 controls, including a prior study of fibrotic interstitial pneumonia). Single nucleotide polymorphisms, classical HLA alleles and amino acids were analysed and signals meeting a region-wide association threshold of p<4.5×10-4 and a posterior probability of replication >90% were considered significant. We sought to replicate the previously reported HLA-DQB1 association in the subset of studies independent of the original report. Results: The meta-analysis of all seven studies identified four significant independent single nucleotide polymorphisms associated with IPF risk. However, none met the posterior probability for replication criterion. The HLA-DQB1 association was not replicated in the independent IPF studies. Conclusion: Variation in the HLA region was not consistently associated with risk in studies of IPF. However, this does not preclude the possibility that other genomic regions linked to the immune response may be involved in the aetiology of IPF.

Utilizing PK and PD Biomarkers to Guide the First-in-Human Starting Dose Selection of MTBT1466A: A Novel Humanized Monoclonal Anti-TGFß3 Antibody for the Treatment of Fibrotic Diseases.

MTBT1466A is a high-affinity TGFß3-specific humanized IgG1 monoclonal antibody with reduced Fc effector function, currently under investigation in clinical trials as a potential anti-fibrotic therapy. Here, we characterized the pharmacokinetics (PK) and pharmacodynamics (PD) of MTBT1466A in mice and monkeys and predicted the PK/PD of MTBT1466A in humans to guide the selection of the first-in-human (FIH) starting dose. MTBT1466A demonstrated a typical IgG1-like biphasic PK profile in monkeys, and the predicted human clearance of 2.69 mL/day/kg and t1/2 of 20.4 days are consistent with those expected for a human IgG1 antibody. In a mouse model of bleomycin-induced lung fibrosis, changes in expression of TGFß3-related genes, serpine1, fibronectin-1, and collagen 1A1 were used as PD biomarkers to determine the minimum pharmacologically active dose of 1 mg/kg. Unlike in the fibrosis mouse model, evidence of target engagement in healthy monkeys was only observed at higher doses. Using a PKPD-guided approach, the recommended FIH dose of 50 mg, IV, provided exposures that were shown to be safe and well tolerated in healthy volunteers. MTBT1466A PK in healthy volunteers was predicted reasonably well using a PK model with allometric scaling of PK parameters from monkey data. Taken together, this work provides insights into the PK/PD behavior of MTBT1466A in preclinical species, and supports the translatability of the preclinical data into the clinic.

Association study of human leukocyte antigen (HLA) variants and idiopathic pulmonary fibrosis.

Introduction: Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial pneumonia marked by progressive lung fibrosis and a poor prognosis. Recent studies have highlighted the potential role of infection in the pathogenesis of IPF and a prior association of the HLA-DQB1 gene with idiopathic fibrotic interstitial pneumonia (including IPF) has been reported. Due to the important role that the Human Leukocyte Antigen (HLA) region plays in the immune response, here we evaluated if HLA genetic variation was associated specifically with IPF risk. Methods: We performed a meta-analysis of associations of the HLA region with IPF risk in individuals of European ancestry from seven independent case-control studies of IPF (comprising a total of 5,159 cases and 27,459 controls, including the prior study of fibrotic interstitial pneumonia). Single nucleotide polymorphisms, classical HLA alleles and amino acids were analysed and signals meeting a region-wide association threshold p<4.5×10-4 and a posterior probability of replication >90% were considered significant. We sought to replicate the previously reported HLA-DQB1 association in the subset of studies independent of the original report. Results: The meta-analysis of all seven studies identified four significant independent single nucleotide polymorphisms associated with IPF risk. However, none met the posterior probability for replication criterion. The HLA-DQB1 association was not replicated in the independent IPF studies. Conclusion: Variation in the HLA region was not consistently associated with risk in studies of IPF. However, this does not preclude the possibility that other genomic regions linked to the immune response may be involved in the aetiology of IPF.

Autologous organoid co-culture model reveals T cell-driven epithelial cell death in Crohn's Disease.

Lympho-epithelial interactions between intestinal T resident memory cells (Trm) and the epithelium have been associated with inflammatory bowel disease (IBD) activity. We developed ex vivo autologous organoid-mucosal T cell cocultures to functionally assess lymphoepithelial interactions in Crohn's Disease (CD) patients compared to controls. We demonstrate the direct epithelial cell death induced by autologous mucosal T cells in CD patients but not in controls. These findings were positively correlated with T cell infiltration of the organoids. This potential was inhibited by limiting lympho-epithelial interactions through CD103 and NKG2D blocking antibodies. These data directly demonstrate for the first time the direct deleterious effect of mucosal T cells on the epithelium of CD patients. Such ex-vivo models are promising techniques to unravel the pathophysiology of these diseases and the potential mode of action of current and future therapies.

Severity of COVID-19 and adverse long-term outcomes: a retrospective cohort study based on a US electronic health record database.

OBJECTIVE: To identify potential risk factors for adverse long-term outcomes (LTOs) associated with COVID-19, using a large electronic health record (EHR) database. DESIGN: Retrospective cohort study. Patients with COVID-19 were assigned into subcohorts according to most intensive treatment setting experienced. Newly diagnosed conditions were classified as respiratory, cardiovascular or mental health LTOs at >30-≤90 or >90-≤180 days after COVID-19 diagnosis or hospital discharge. Multivariate regression analysis was performed to identify any association of treatment setting (as a proxy for disease severity) with LTO incidence. SETTING: Optum deidentified COVID-19 EHR dataset drawn from hospitals and clinics across the USA. PARTICIPANTS: Individuals diagnosed with COVID-19 (N=57 748) from 20 February to 4 July 2020. MAIN OUTCOMES: Incidence of new clinical conditions after COVID-19 diagnosis or hospital discharge and the association of treatment setting (as a proxy for disease severity) with their risk of occurrence. RESULTS: Patients were assigned into one of six subcohorts: outpatient (n=22 788), emergency room (ER) with same-day COVID-19 diagnosis (n=11 633), ER with COVID-19 diagnosis≤21 days before ER visit (n=2877), hospitalisation without intensive care unit (ICU; n=16 653), ICU without ventilation (n=1837) and ICU with ventilation (n=1960). Respiratory LTOs were more common than cardiovascular or mental health LTOs across subcohorts and LTO incidence was higher in hospitalised versus non-hospitalised subcohorts. Patients with the most severe disease were at increased risk of respiratory (risk ratio (RR) 1.86, 95% CI 1.56 to 2.21), cardiovascular (RR 2.65, 95% CI 1.49 to 4.43) and mental health outcomes (RR 1.52, 95% CI 1.20 to 1.91) up to 6 months after hospital discharge compared with outpatients. CONCLUSIONS: Patients with severe COVID-19 had increased risk of new clinical conditions up to 6 months after hospital discharge. The extent that treatment setting (eg, ICU) contributed to these conditions is unknown, but strategies to prevent COVID-19 progression may nonetheless minimise their occurrence.

Serum Lysophosphatidic Acid Measurement by Liquid Chromatography-Mass Spectrometry in COPD Patients.

Lysophospholipids are bioactive signaling molecules derived from cell membrane glycerophospholipids or sphingolipids and are highly regulated under normal physiological conditions. Lysophosphatidic acids (LPAs) are a class of lysophospholipids that act on G-protein-coupled receptors to exert a variety of cellular functions. Dysregulation of phospholipase activity and consequently LPA synthesis in serum have been linked to inflammation, such as seen in chronic obstructive pulmonary disease (COPD). The accurate measurement of phospholipids is critical for evaluating their dysregulation in disease. In this study, we optimized experimental parameters for the sensitive measurement of LPAs. We validated the method based on matrix, linearity, accuracy, precision, and stability. An investigation into sample extraction processes emphasized that the common practice of including low concentration of hydrochloric acid in the extraction buffer causes an overestimation of lipid recovery. The liquid chromatography gradient was optimized to separate various lysophospholipid classes. After optimization, detection limits of LPA were sufficiently sensitive for subsequent analysis, ranging from 2 to 8 nM. The validated workflow was applied to a cohort of healthy donor and COPD patient sera. Eight LPA species were identified, and five unique species of LPA were quantified. Most LPA species increased significantly in COPD patients compared to healthy donors. The correlation between LPAs and other demographic parameters was further investigated in a sample set of over 200 baseline patient sera from a COPD clinical trial. For the first time, LPAs other than the two most abundant and readily detectable moieties are quantified in COPD patients using validated methods, opening the door to downstream biomarker evaluation in respiratory disease.

Comparison of genome-wide gene expression profiling by RNA Sequencing versus microarray in bronchial biopsies of COPD patients before and after inhaled corticosteroid treatment: does it provide new insights?

More DEGs are detected by RNA-Seq than microarrays in COPD lung biopsies and are associated with immunological pathways. Performing bulk tissue cell-type deconvolution in microarray lung samples, using the SVR method, reflects RNA-Seq results. https://bit.ly/2N8sY3s.

A Phase 1b Study of Vismodegib with Pirfenidone in Patients with Idiopathic Pulmonary Fibrosis.

INTRODUCTION: Components of the hedgehog signaling pathway are upregulated in patients with idiopathic pulmonary fibrosis (IPF). Vismodegib, a small-molecule inhibitor of hedgehog signaling, when used in combination with currently available antifibrotic therapy, may be more efficacious than antifibrotics alone. The objective of this study was to evaluate the safety and tolerability of vismodegib plus pirfenidone in patients with IPF. METHODS: Twenty-one patients were enrolled in a phase 1b open-label trial to receive vismodegib 150 mg plus pirfenidone 2403 mg/day once daily. Key endpoints were safety, tolerability, and pharmacokinetics. Exploratory endpoints included change from baseline to week 24 in % predicted forced vital capacity (FVC) and University of California, San Diego Shortness of Breath Questionnaire (UCSD-SOBQ) scores, as well as pharmacodynamic changes in hedgehog biomarker C-X-C motif chemokine ligand 14 (CXCL14). RESULTS: All patients reported at least one treatment-emergent adverse event (AE), most frequently muscle spasms (76.2%). Serious AEs were reported in 14.3% of patients; one event of dehydration was considered related to vismodegib. One patient died due to IPF progression, unrelated to either treatment. More patients discontinued vismodegib than pirfenidone (42.9% vs. 33.3%, respectively). Changes from baseline to week 24 in % predicted FVC and UCSD-SOBQ scores were within known endpoint variability. In contrast to findings in basal cell carcinoma, vismodegib had no effect on circulating CXCL14 levels. CONCLUSION: The safety profile was generally consistent with the known profiles of both drugs, with no new safety signals observed in this small cohort. There was no pharmacodynamic effect on CXCL14 levels. Future development of vismodegib for IPF may be limited due to tolerability issues. TRIAL REGISTRATION: ClinicalTrials.gov NCT02648048. Plain language summary available for this article. FUNDING: F. Hoffmann-La Roche Ltd. and Genentech, Inc.

Antigen-engaged B cells undergo chemotaxis toward the T zone and form motile conjugates with helper T cells.

Interactions between B and T cells are essential for most antibody responses, but the dynamics of these interactions are poorly understood. By two-photon microscopy of intact lymph nodes, we show that upon exposure to antigen, B cells migrate with directional preference toward the B-zone-T-zone boundary in a CCR7-dependent manner, through a region that exhibits a CCR7-ligand gradient. Initially the B cells show reduced motility, but after 1 d, motility is increased to approximately 9 microm/min. Antigen-engaged B cells pair with antigen-specific helper T cells for 10 to more than 60 min, whereas non-antigen-specific interactions last less than 10 min. B cell-T cell conjugates are highly dynamic and migrate extensively, being led by B cells. B cells occasionally contact more than one T cell, whereas T cells are strictly monogamous in their interactions. These findings provide evidence of lymphocyte chemotaxis in vivo, and they begin to define the spatiotemporal cellular dynamics associated with T cell-dependent antibody responses.