Williamson Ziegler Bradford

A phase 3 trial of pirfenidone in patients with idiopathic pulmonary fibrosis.

BACKGROUND In two of three phase 3 trials, pirfenidone, an oral antifibrotic therapy, reduced disease progression, as measured by the decline in forced vital capacity (FVC) or vital capacity, in patients with idiopathic pulmonary fibrosis; in the third trial, this end point was not achieved. We sought to confirm the beneficial effect of pirfenidone on disease progression in such patients. METHODS In this phase 3 study, we randomly assigned 555 patients with idiopathic pulmonary fibrosis to receive either oral pirfenidone (2403 mg per day) or placebo for 52 weeks. The primary end point was the change in FVC or death at week 52. Secondary end points were the 6-minute walk distance, progression-free survival, dyspnea, and death from any cause or from idiopathic pulmonary fibrosis. RESULTS In the pirfenidone group, as compared with the placebo group, there was a relative reduction of 47.9% in the proportion of patients who had an absolute decline of 10 percentage points or more in the percentage of the predicted FVC or who died; there was also a relative increase of 132.5% in the proportion of patients with no decline in FVC (P<0.001). Pirfenidone reduced the decline in the 6-minute walk distance (P=0.04) and improved progression-free survival (P<0.001). There was no significant between-group difference in dyspnea scores (P=0.16) or in rates of death from any cause (P=0.10) or from idiopathic pulmonary fibrosis (P=0.23). However, in a prespecified pooled analysis incorporating results from two previous phase 3 trials, the between-group difference favoring pirfenidone was significant for death from any cause (P=0.01) and from idiopathic pulmonary fibrosis (P=0.006). Gastrointestinal and skin-related adverse events were more common in the pirfenidone group than in the placebo group but rarely led to treatment discontinuation. CONCLUSIONS Pirfenidone, as compared with placebo, reduced disease progression, as reflected by lung function, exercise tolerance, and progression-free survival, in patients with idiopathic pulmonary fibrosis. Treatment was associated with an acceptable side-effect profile and fewer deaths. (Funded by InterMune; ASCEND ClinicalTrials.gov number, NCT01366209.).

Pirfenidone in patients with idiopathic pulmonary fibrosis (CAPACITY): two randomised trials.

BACKGROUND Idiopathic pulmonary fibrosis is a progressive and fatal lung disease with inevitable loss of lung function. The CAPACITY programme (studies 004 and 006) was designed to confirm the results of a phase 2 study that suggested that pirfenidone, a novel antifibrotic and anti-inflammatory drug, reduces deterioration in lung function in patients with idiopathic pulmonary fibrosis. METHODS In two concurrent trials (004 and 006), patients (aged 40-80 years) with idiopathic pulmonary fibrosis were randomly assigned to oral pirfenidone or placebo for a minimum of 72 weeks in 110 centres in Australia, Europe, and North America. In study 004, patients were assigned in a 2:1:2 ratio to pirfenidone 2403 mg/day, pirfenidone 1197 mg/day, or placebo; in study 006, patients were assigned in a 1:1 ratio to pirfenidone 2403 mg/day or placebo. The randomisation code (permuted block design) was computer generated and stratified by region. All study personnel were masked to treatment group assignment until after final database lock. Treatments were administered orally, 801 mg or 399 mg three times a day. The primary endpoint was change in percentage predicted forced vital capacity (FVC) at week 72. Analysis was by intention to treat. The studies are registered with ClinicalTrials.gov, numbers NCT00287729 and NCT00287716. FINDINGS In study 004, 174 of 435 patients were assigned to pirfenidone 2403 mg/day, 87 to pirfenidone 1197 mg/day, and 174 to placebo. In study 006, 171 of 344 patients were assigned to pirfenidone 2403 mg/day, and 173 to placebo. All patients in both studies were analysed. In study 004, pirfenidone reduced decline in FVC (p=0·001). Mean FVC change at week 72 was -8·0% (SD 16·5) in the pirfenidone 2403 mg/day group and -12·4% (18·5) in the placebo group (difference 4·4%, 95% CI 0·7 to 9·1); 35 (20%) of 174 versus 60 (35%) of 174 patients, respectively, had a decline of at least 10%. A significant treatment effect was noted at all timepoints from week 24 and in an analysis over all study timepoints (p=0·0007). Mean change in percentage FVC in the pirfenidone 1197 mg/day group was intermediate to that in the pirfenidone 2403 mg/day and placebo groups. In study 006, the difference between groups in FVC change at week 72 was not significant (p=0·501). Mean change in FVC at week 72 was -9·0% (SD 19·6) in the pirfenidone group and -9·6% (19·1) in the placebo group, and the difference between groups in predicted FVC change at week 72 was not significant (0·6%, -3·5 to 4·7); however, a consistent pirfenidone effect was apparent until week 48 (p=0·005) and in an analysis of all study timepoints (p=0·007). Patients in the pirfenidone 2403 mg/day group had higher incidences of nausea (125 [36%] of 345 vs 60 [17%] of 347), dyspepsia (66 [19%] vs 26 [7%]), vomiting (47 [14%] vs 15 [4%]), anorexia (37 [11%] vs 13 [4%]), photosensitivity (42 [12%] vs 6 [2%]), rash (111 [32%] vs 40 [12%]), and dizziness (63 [18%] vs 35 [10%]) than did those in the placebo group. Fewer overall deaths (19 [6%] vs 29 [8%]) and fewer deaths related to idiopathic pulmonary fibrosis (12 [3%] vs 25 [7%]) occurred in the pirfenidone 2403 mg/day groups than in the placebo groups. INTERPRETATION The data show pirfenidone has a favourable benefit risk profile and represents an appropriate treatment option for patients with idiopathic pulmonary fibrosis. FUNDING InterMune.

The Clinical Course of Patients with Idiopathic Pulmonary Fibrosis

Context The natural history of idiopathic pulmonary fibrosis (IPF) is unclear. Contribution A total of 168 participants with mild to moderate IPF assigned to placebo in a randomized trial were followed at 12-week intervals for about 76 weeks. For 32 of 36 patients who died, IPF was a related or main cause of death. Although physiologic variables such as FVC changed little, acute clinical deterioration preceded death in half of the patients who died of IPF. Implications Clinicians may need to rethink referral timing for lung transplantation because many patients with IPF may experience precipitous clinical declines rather than gradual progression of disease. The Editors Idiopathic pulmonary fibrosis (IPF), the most frequent of the idiopathic interstitial pneumonias, is associated with the worst prognosis (1, 2). However, data on the natural history of IPF are sparse. To clearly describe the pace of progression and the cause of death in a well-characterized cohort with mild to moderate IPF, we analyzed data from the placebo group of a randomized, double-blind, controlled clinical trial evaluating therapy with interferon-1b in patients with IPF (3). These data provide important insight into the natural history of IPF and events preceding death in patients with IPF. The data suggest that a gradual, progressive decline does not occur in many patients, thereby supporting the need for early referral for lung transplantation. Methods Overview Using data from a recently completed clinical trial (3), we performed a series of exploratory analyses of physiologic variables, dyspnea measures, hospitalizations, and characteristics of mortality in patients randomly assigned to receive placebo. The prespecified primary end point analysis for the phase III study was to occur after the 306th randomly assigned patient was scheduled to complete 48 weeks of therapy. Patients were enrolled over an approximately 1-year period. Thus, follow-up times for the patients varied, and the numbers of patients available for visits beyond 48 weeks diminished over time. In the published report of the primary analysis of the trial, the median length of observation was 58 weeks (3). In the current report, we summarize data from randomization through the completion of blinded study therapy (the observation period); the median for this period was 76 weeks. Study Participants Study participants were all patients randomly assigned to the placebo group (n= 168) in the trial (3). Criteria for enrollment included a diagnosis of IPF according to American Thoracic Society criteria (4), an FVC of 50% to 90%, diffusing capacity of carbon monoxide (DLco) of 25% or greater, definite or probable IPF on high-resolution computed tomography according to prespecified criteria, and worsening of disease during the preceding year despite a total corticosteroid dose of 1800 mg or greater within the preceding 2 years (3). Patients were permitted to continue taking prednisone (15 mg/d) if the dosage remained stable. Data Collection Data were collected at 12-week intervals and recorded on standardized case report forms by trained research associates at each institution. Information derived from interview and examination of the patient included demographic and clinical data, physiologic assessments, measures of dyspnea, vital status, number of all-cause hospitalizations, and number of hospitalizations for which the primary reason was specified as respiratory. Physiologic measures included FVC, plethysmography, Dlco, and arterial blood gas at room-air ambient temperatures. The transition dyspnea score is derived from an instrument in which the patient assesses the extent of dyspnea in reference to his or her baseline at study entry (5). The transitions or changes in the patients dyspnea in 3 categories (function impairment, magnitude of task needed to evoke dyspnea, and magnitude of effort needed to evoke dyspnea) are rated in 7 grades from 3 (major deterioration) to 0 (unchanged) to 3 (major improvement); the final score ranged from 9 to 9. The lower the total score, the more severe the dyspnea. The validated University of California, San Diego, Shortness of Breath Questionnaire (6) has 24 items: Patients are asked to rate severity of shortness of breath using a 6-point scale (0 = not at all; 5 = maximal severity) during 21 different activities of daily living associated with varying levels of exertion; they are also asked to rate how their daily lives are limited by shortness of breath, fear of harm from overexertion, and fear of shortness of breath. Scores range from 0 to 120, with increasing score indicating worsening quality of life. The physician responsible for any patient who died during the study period completed a retrospective supplemental questionnaire. The investigator-physician, who had full access to all measurements obtained as a part of the study, specified the primary cause of death, whether the cause was respiratory, and whether death was related to IPF. Investigator-physicians were to cite IPF as the primary cause of death only in the absence of a known alternative cause and only if the event was witnessed. For deaths considered to be IPF-related, 1 of 4 categories was assigned on the basis of the interval from the onset of new or worsening symptoms or signs until death: abrupt (occurring within minutes to hours), acute (4 weeks), subacute (progressing over weeks or months), or unknown. In the current report, we combine the abrupt- and acute-onset events within a single category. Statistical Analysis Physiologic variables and measures of dyspnea were compared between baseline and week 72. The frequency of hospitalizations (all-cause and respiratory-related), number of hospital days in patients hospitalized, and mortality were assessed over the entire observation period. Mean values are followed by SDs. The relationships between baseline percentage predicted FVC and the incidence and length of hospitalization were examined by using the Fisher exact test or independent-sample t-test, as appropriate. Missing values were not imputed. The reasons for missing values are as follows: 1) To optimize data integrity, data obtained at visits outside a window of 7 days were not included in the analysis, 2) because trial enrollment was staggered, fewer patients were available for analysis at the latter time points, and 3) the value for a particular variable for a particular patient may be missing, even though all other values for that time point and patient are available. On the basis of the nature of the variations leading to the differences in available data over time, no apparent evidence indicated that the variations are not random. Data analyses were conducted by using SAS software, version 8.02 (SAS Institute, Inc., Cary, North Carolina). Role of the Funding Source InterMune, Inc., funded this study. Authors from InterMune (Drs. Safrin, Starko, and Bradford) participated in the design and analysis of the study, as did the other authors. All authors had full access to the data. The funding source had no role in the decision to publish the results. Results Patients We analyzed 168 patients (mean age, 64 years, SD 9). Most patients were male (66%), white (86%), and nonsmokers (that is, never-smokers or ex-smokers) (91%). Mean time since the diagnosis of IPF was 378 days, SD, 295. The diagnosis of IPF was confirmed by surgical lung biopsy in 58% of patients; in 83%, findings on high-resolution computed tomography met prespecified criteria for definite IPF. At study entry, 31% of patients used supplemental oxygen and 82% were receiving systemic corticosteroids. During the observation period, 2 patients (1.2%) used azathioprine and 1 patient (0.6%) used cyclophosphamide. Physiologic Variables and Measures of Dyspnea For patients who survived to week 72, the mean percentage predicted FVC decreased from 64.5%, SD 11.1%, to 61.0%, SD 14.1%; the mean percentage predicted DLco decreased from 37.8%, SD 11.1%, to 37.0%, SD 19.9%; and the mean alveolararterial gradient increased from 23.2 mm Hg, SD 10.9, to 26.9 mm Hg, SD 13.0. The mean transition dyspnea index score was 1.29, SD 3.6, at week 72, indicating worsening dyspnea, whereas the mean University of California, San Diego, Shortness of Breath Questionnaire score changed minimally (from 45.1, SD 23.4, to 46.8, SD 25.1) (Figure 1). For patients who died during the trial, we observed a general trend toward increases in alveolararterial gradient and dyspnea and toward decreases in FVC and DLco (Figure 2). The spaghetti plots (Figure 2) highlight the finding that although dyspnea or alveolararterial gradient often increased sharply before a patients death, significant intrapatient variability occurs over time. Figure 1. Measures of physiology and dyspnea from study entry through week 72 for patients who survived throughout trial. Figure 2. Measures of physiology and dyspnea for each of the 36 patients who died during the trial; each line represents a single patient. Hospitalizations Fifty-seven (34%) patients had a total of 95 all-cause hospitalizations during the observation period. Among those hospitalized, the mean total number of hospital days was 14.3, SD 13.5. Thirty-eight (23%) patients had 57 hospitalizations for a respiratory disorder, with a mean total number of hospital days of 15.0, SD 14.6. The most commonly reported reason for respiratory hospitalization (33%) was presumed infection. When stratified by the baseline median percentage predicted FVC, patients with more severely impaired lung function (62%) were more likely to be hospitalized for any reason than patients with baseline percentage predicted FVC greater than 62%35 (42%) versus 22 (26%) patients (P= 0.05) and 58 versus 37 hospitalizations overall. Respiratory hospitalizations were similarly more frequent in the subset of patients with baseline FVC of 62% or less: 25 (30%) versus 13 (15%) patients (P= 0.04). In hospitalized patients, the total number

Effect of interferon gamma-1b on survival in patients with idiopathic pulmonary fibrosis (INSPIRE): a multicentre, randomised, placebo-controlled trial

BACKGROUND Idiopathic pulmonary fibrosis is a fatal disease for which no effective treatment exists. We assessed whether treatment with interferon gamma-1b improved survival compared with placebo in patients with idiopathic pulmonary fibrosis and mild-to-moderate impairment of pulmonary function. METHODS 826 patients with idiopathic pulmonary fibrosis were enrolled from 81 centres in seven European countries, the USA, and Canada. Patients were randomly assigned (double-blind) in a 2:1 ratio to receive 200 microg interferon gamma-1b (n=551) or equivalent placebo (n=275) subcutaneously, three times per week. Eligible patients were aged 40-79 years, had been diagnosed in the past 48 months, had a forced vital capacity of 55-90% of the predicted value, and a haemoglobin-corrected carbon monoxide diffusing capacity of 35-90% of the predicted value. The primary endpoint was overall survival time from randomisation measured at the second interim analysis, when the proportion of deaths had reached 75% of those expected by the study conclusion. This study is registered with ClinicalTrials.gov, number NCT00075998. FINDINGS At the second interim analysis, the hazard ratio for mortality in patients on interferon gamma-1b showed absence of minimum benefit compared with placebo (1.15, 95% CI 0.77-1.71, p=0.497), and indicated that the study should be stopped. After a median duration of 64 weeks (IQR 41-84) on treatment, 80 (15%) patients on interferon gamma-1b and 35 (13%) on placebo had died. Almost all patients reported at least one adverse event, and more patients on interferon gamma-1b group had constitutional signs and symptoms (influenza-like illness, fatigue, fever, and chills) than did those on placebo. Occurrence of serious adverse events (eg, pneumonia, respiratory failure) was similar for both treatment groups. Treatment adherence was good and few patients discontinued treatment prematurely in either group. INTERPRETATION We cannot recommend treatment with interferon gamma-1b since the drug did not improve survival for patients with idiopathic pulmonary fibrosis, which refutes previous findings from subgroup analyses of survival in studies of patients with mild-to-moderate physiological impairment of pulmonary function. FUNDING InterMune.

Genome-wide association study identifies multiple susceptibility loci for pulmonary fibrosis

We performed a genome-wide association study of non-Hispanic, white individuals with fibrotic idiopathic interstitial pneumonias (IIPs; n = 1,616) and controls (n = 4,683), with follow-up replication analyses in 876 cases and 1,890 controls. We confirmed association with TERT at 5p15, MUC5B at 11p15 and the 3q26 region near TERC, and we identified seven newly associated loci (Pmeta = 2.4 × 10−8 to 1.1 × 10−19), including FAM13A (4q22), DSP (6p24), OBFC1 (10q24), ATP11A (13q34), DPP9 (19p13) and chromosomal regions 7q22 and 15q14-15. Our results suggest that genes involved in host defense, cell-cell adhesion and DNA repair contribute to risk of fibrotic IIPs.

Ascertainment of Individual Risk of Mortality for Patients with Idiopathic Pulmonary Fibrosis

RATIONALE Several predictors of mortality in patients with idiopathic pulmonary fibrosis have been described; however, there is a need for a practical and accurate method of quantifying the prognosis of individual patients. OBJECTIVES Develop a practical mortality risk scoring system for patients with idiopathic pulmonary fibrosis. METHODS We used a Cox proportional hazards model and data from two clinical trials (n = 1,099) to identify independent predictors of 1-year mortality among patients with idiopathic pulmonary fibrosis. From the comprehensive model, an abbreviated clinical model comprised of only those predictors that are readily and reliably ascertained by clinicians was derived. Beta coefficients for each predictor were then used to develop a practical mortality risk scoring system. MEASUREMENTS AND MAIN RESULTS Independent predictors of mortality included age, respiratory hospitalization, percent predicted FVC, 24-week change in FVC, percent predicted carbon monoxide diffusing capacity, 24-week change in percent predicted carbon monoxide diffusing capacity, and 24-week change in health-related quality of life. An abbreviated clinical model comprising only four predictors (age, respiratory hospitalization, percent predicted FVC, and 24-wk change in FVC), and the corresponding risk scoring system produced estimates of 1-year mortality risk consistent with observed data (9.9% vs. 9.7%; C statistic = 0.75; 95% confidence interval, 0.71–0.79). CONCLUSIONS The prognosis for patients with idiopathic pulmonary fibrosis may be accurately determined using four readily ascertainable predictors. Our simplified scoring system may be a valuable tool for determining prognosis and guiding clinical management. Additional research is needed to validate the applicability and accuracy of the scoring system.

Six-minute-walk test in idiopathic pulmonary fibrosis: test validation and minimal clinically important difference.

RATIONALE The 6-minute-walk test (6MWT) is a practical and clinically meaningful measure of exercise tolerance with favorable performance characteristics in various cardiac and pulmonary diseases. Performance characteristics in patients with idiopathic pulmonary fibrosis (IPF) have not been systematically evaluated. OBJECTIVES To assess the reliability, validity, and responsiveness of the 6MWT and estimate the minimal clinically important difference (MCID) in patients with IPF. METHODS The study population included all subjects completing a 6MWT in a clinical trial evaluating interferon gamma-1b (n = 822). Six-minute walk distance (6MWD) and other parameters were measured at baseline and at 24-week intervals using a standardized protocol. Parametric and distribution-independent correlation coefficients were used to assess the strength of the relationships between 6MWD and measures of pulmonary function, dyspnea, and health-related quality of life. Both distribution-based and anchor-based methods were used to estimate the MCID. MEASUREMENTS AND MAIN RESULTS Comparison of two proximal measures of 6MWD (mean interval, 24 d) demonstrated good reliability (coefficient = 0.83; P < 0.001). 6MWD was weakly correlated with measures of physiologic function and health-related quality of life; however, values were consistently and significantly lower for patients with the poorest functional status, suggesting good construct validity. Importantly, change in 6MWD was highly predictive of mortality; a 24-week decline of greater than 50 m was associated with a fourfold increase in risk of death at 1 year (hazard ratio, 4.27; 95% confidence interval, 2.57- 7.10; P < 0.001). The estimated MCID was 24-45 m. CONCLUSIONS The 6MWT is a reliable, valid, and responsive measure of disease status and a valid endpoint for clinical trials in IPF.

Forced vital capacity in patients with idiopathic pulmonary fibrosis: test properties and minimal clinically important difference.

RATIONALE Forced vital capacity (FVC) is an established measure of pulmonary function in idiopathic pulmonary fibrosis (IPF). Evidence regarding its measurement properties and minimal clinically important difference (MCID) in this population is limited. OBJECTIVES To assess the reliability, validity, and responsiveness of FVC and estimate the MCID in patients with IPF. METHODS The study population included all 1,156 randomized patients in two clinical trials of IFN-γ1b. FVC and other measures of functional status were measured at screening or baseline and 24-week intervals thereafter. Reliability was assessed based on two proximal measures of FVC, validity was assessed based on correlations between FVC and other measures of functional status, and responsiveness was assessed based on the relationship between 24-week changes in FVC and other measures of functional status. Distribution-based and anchor-based methods were used to estimate the MCID. MEASUREMENTS AND MAIN RESULTS Correlation of percent-predicted FVC between measurements (mean interval, 18 d) was high (r = 0.93; P < 0.001). Correlations between FVC and other parameters were generally weak, with the strongest observed correlation between FVC and carbon monoxide diffusing capacity (r = 0.38; P < 0.001). Correlations between change in FVC and changes in other parameters were slightly stronger (range, r = 0.16-0.37; P < 0.001). Importantly, 1-year risk of death was more than twofold higher (P < 0.001) in patients with a 24-week decline in FVC between 5% and 10%. The estimated MCID was 2-6%. CONCLUSIONS FVC is a reliable, valid, and responsive measure of clinical status in patients with IPF, and a decline of 2-6%, although small, represents a clinically important difference.

Pirfenidone for idiopathic pulmonary fibrosis: Analysis of pooled data from three multinational phase 3 trials

Pirfenidone is an antifibrotic agent that has been evaluated in three multinational phase 3 trials in patients with idiopathic pulmonary fibrosis (IPF). We analysed pooled data from the multinational trials to obtain the most precise estimates of the magnitude of treatment effect on measures of disease progression. All patients randomised to pirfenidone 2403 mg·day−1 or placebo in the CAPACITY or ASCEND studies were included in the analysis. Pooled analyses of outcomes at 1 year were based on the pre-specified end-points and analytic methods described in the ASCEND study protocol. A total of 1247 patients were included in the analysis. At 1 year, pirfenidone reduced the proportion of patients with a ≥10% decline in per cent predicted forced vital capacity or death by 43.8% (95% CI 29.3–55.4%) and increased the proportion of patients with no decline by 59.3% (95% CI 29.0–96.8%). A treatment benefit was also observed for progression-free survival, 6-min walk distance and dyspnoea. Gastrointestinal and skin-related adverse events were more common in the pirfenidone group, but rarely led to discontinuation. Analysis of data from three phase 3 trials demonstrated that treatment with pirfenidone for 1 year resulted in clinically meaningful reductions in disease progression in patients with IPF. Treatment with pirfenidone for 1 year results in clinically meaningful reductions in IPF disease progression http://ow.ly/StvBk

All-Cause Mortality Rate in Patients with Idiopathic Pulmonary Fibrosis. Implications for the Design and Execution of Clinical Trials

RATIONALE FVC has emerged as a standard primary endpoint in clinical trials evaluating novel therapies for patients with idiopathic pulmonary fibrosis (IPF). However, it has recently been proposed that all-cause mortality or a composite comprised of all-cause mortality and all-cause nonelective hospitalization be adopted as the standard primary endpoint for IPF clinical trials. OBJECTIVES To conduct a comprehensive evaluation of mortality in three phase 3 clinical trials and evaluate the feasibility of mortality trials in patients with IPF. METHODS The study population included 622 patients randomized to placebo in the CAPACITY studies evaluating pirfenidone (n = 347) or the INSPIRE study evaluating interferon-γ1b (n = 275). The Kaplan-Meier estimate of 2-year survival was fit to the exponential distribution and used to calculate sample size requirements for a mortality study with 90% power to detect a 25% reduction in all-cause mortality with a two-sided α of 0.05. Modeling analyses were used to assess the effects of selected variables on sample size and study design. MEASUREMENTS AND MAIN RESULTS A total of 73 deaths occurred during the period of observation (mean duration of follow-up, 80.1 wk). The all-cause mortality rate was 6.6% at 1 year and 13.7% at 2 years. Based on the observed 2-year mortality rate, a total of 508 events would be required to detect a significant treatment benefit in a two-arm trial with 90% power to detect a 25% reduction in all-cause mortality. The estimated sample size for a trial enrolled over 3 years with a maximum follow-up period of 5 years is 2,582 patients. CONCLUSIONS The all-cause mortality rate is relatively low in patients with IPF with mild to moderate impairment in lung function. Accordingly, the necessary size, duration, and cost of all-cause mortality trials in this population are substantial and likely prohibitive.