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Background: Overall Disability Response Score (ODRS) is a composite endpoint including Expanded Disability Status Scale, Timed 25-foot Walk, and 9-Hole Peg Test, designed to quantify both disability improvement and worsening in multiple sclerosis (MS). Objective: To assess the sensitivity and clinical meaningfulness of ODRS using natalizumab Phase 3 data sets (AFFIRM in relapsing-remitting MS and ASCEND in secondary progressive MS). Methods: Differences in ODRS over 96 weeks, ODRS at Week 96, and slope of ODRS change per year between natalizumab and placebo groups were analyzed. Correlation between ODRS and changes in patient-reported outcomes was also analyzed. Results: The difference (95% confidence interval (CI)) in the ODRS over 96 weeks between natalizumab and placebo groups was 0.34 (0.21–0.46) in AFFIRM ( p Conclusion: This analysis supports ODRS as a sensitive and potentially clinically meaningful disability outcome measure in MS.

Objective: To understand how longitudinal serum neurofilament light chain (sNfL) patterns can inform its use as a prognostic biomarker in multiple sclerosis (MS) and evaluate whether sNfL reflects MS disease activity and disease-modifying therapy usage. Methods: This was a post hoc analysis of longitudinal data and samples from the ADVANCE trial (NCT00906399) of patients with relapsing–remitting MS (RRMS). sNfL was measured every 3 months for 2 years, then every 6 months for 4 years. Regression models explored how sNfL data predicted 4-year values of brain volume, expanded disability status scale score, and T2 lesions. sNfL levels were assessed in those receiving placebo, peginterferon beta-1a, and those with disease activity. Results: Baseline sNfL was a predictor of 4-year brain atrophy and development of new T2 lesions. Clinical ( p = 0.02) and magnetic resonance imaging (MRI) ( p Conclusion: These data support sNfL as a prognostic and disease-monitoring biomarker for RRMS.

Peginterferon beta-1a reduced annualized relapse rate as compared with placebo and was approved to treat multiple sclerosis patients. A population pharmacokinetic and an exposure-efficacy model were developed to establish the quantitative relationship between pharmacokinetics and annualized relapse rate. The pharmacokinetics was well described by a 1-compartment model with first-order absorption and linear elimination kinetics. Body mass index was the most significant covariate that impacted both clearance and volume of distribution, which in turn impacted area under the curve and maximum serum concentration. Cumulative monthly area under the curve and annualized relapse rate were best described by a Poisson-gamma (negative binomial) model, demonstrating that the improved efficacy of every-2-weeks dosing was driven by greater drug exposure. The results supported the superior efficacy of the every-2-week dosing regimen compared with the every-4-weeks dosing regimen.

The effect of subcutaneous (SC) peginterferon β-1a exposure on reduction of gadolinium-enhanced (Gd+) lesion count over time was evaluated in patients with relapsing-remitting multiple sclerosis (RRMS) in a Phase 3 study (ADVANCE). Patients were randomized to receive SC injections of placebo (n = 500), 125 mcg every-2-weeks (n = 512), or 125 mcg every-4-weeks (n = 500) for 1 year, and then active treatment in the second year. Steady state 4-week AUC (AUCss) was derived for each individual based on sparse pharmacokinetic (PK) sample and a population PK model. Several longitudinal count models, including marginal, mixed effect, and mixture models, were compared to explore the relationship between AUCss and Gd+ lesion count (or T2 lesion count). A mixture model which divided subjects into two subpopulations by low and high baseline lesion activity was found to yield best goodness-of-fit for the data. In this model, the point estimate and 95 % CI for drug effect slope on log(λ) are −0.0256 (−0.0304, −0.0216) for Gd+ lesion and −0.0147 (−0.0170, −0.0124) for T2 lesion. This suggested that reduction of Gd+ lesion (or T2 lesion) count over time is significantly related to SC peginterferon β-1a exposure, and that the increased reduction lesion count with the every-2-week regimen versus the every-4-week regimen was driven by the higher exposure achieved in that treatment arm (mean Gd+ lesion count 0.2 and 0.7 at Year 2, respectively). The every-2-week regimen produced an exposure range that was close to the plateau range of the exposure–response curve, supporting its selection as the regulatory approved dosage. Electronic supplementary material The online version of this article (doi:10.1007/s10928-016-9477-x) contains supplementary material, which is available to authorized users.

BACKGROUND: Although several disease-modifying treatments are available for relapsing multiple sclerosis, treatment effects have been more modest in progressive multiple sclerosis and have been observed particularly in actively relapsing subgroups or those with lesion activity on imaging. We sought to assess whether natalizumab slows disease progression in secondary progressive multiple sclerosis, independent of relapses.METHODS: ASCEND was a phase 3, randomised, double-blind, placebo-controlled trial (part 1) with an optional 2 year open-label extension (part 2). Enrolled patients aged 18-58 years were natalizumab-naive and had secondary progressive multiple sclerosis for 2 years or more, disability progression unrelated to relapses in the previous year, and Expanded Disability Status Scale (EDSS) scores of 3·0-6·5. In part 1, patients from 163 sites in 17 countries were randomly assigned (1:1) to receive 300 mg intravenous natalizumab or placebo every 4 weeks for 2 years. Patients were stratified by site and by EDSS score (3·0-5·5 vs 6·0-6·5). Patients completing part 1 could enrol in part 2, in which all patients received natalizumab every 4 weeks until the end of the study. Throughout both parts, patients and staff were masked to the treatment received in part 1. The primary outcome in part 1 was the proportion of patients with sustained disability progression, assessed by one or more of three measures: the EDSS, Timed 25-Foot Walk (T25FW), and 9-Hole Peg Test (9HPT). The primary outcome in part 2 was the incidence of adverse events and serious adverse events. Efficacy and safety analyses were done in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT01416181.FINDINGS: Between Sept 13, 2011, and July 16, 2015, 889 patients were randomly assigned (n=440 to the natalizumab group, n=449 to the placebo group). In part 1, 195 (44%) of 439 natalizumab-treated patients and 214 (48%) of 448 placebo-treated patients had confirmed disability progression (odds ratio [OR] 0·86; 95% CI 0·66-1·13; p=0·287). No treatment effect was observed on the EDSS (OR 1·06, 95% CI 0·74-1·53; nominal p=0·753) or the T25FW (0·98, 0·74-1·30; nominal p=0·914) components of the primary outcome. However, natalizumab treatment reduced 9HPT progression (OR 0·56, 95% CI 0·40-0·80; nominal p=0·001). In part 1, 100 (22%) placebo-treated and 90 (20%) natalizumab-treated patients had serious adverse events. In part 2, 291 natalizumab-continuing patients and 274 natalizumab-naive patients received natalizumab (median follow-up 160 weeks [range 108-221]). Serious adverse events occurred in 39 (13%) patients continuing natalizumab and in 24 (9%) patients initiating natalizumab. Two deaths occurred in part 1, neither of which was considered related to study treatment. No progressive multifocal leukoencephalopathy occurred.INTERPRETATION: Natalizumab treatment for secondary progressive multiple sclerosis did not reduce progression on the primary multicomponent disability endpoint in part 1, but it did reduce progression on its upper-limb component. Longer-term trials are needed to assess whether treatment of secondary progressive multiple sclerosis might produce benefits on additional disability components.FUNDING: Biogen.

Heart failure with preserved ejection fraction (HFpEF) is prevalent and often accompanied by metabolic syndrome. Current treatment options are limited. Here, we test the hypothesis that combined A1/A2B adenosine receptor blockade is beneficial in obese ZSF1 rats, an animal model of HFpEF with metabolic syndrome. The combined A1/A2B receptor antagonist 3-[4-(2,6-dioxo-1,3-dipropyl-7H-purin-8-yl)-1-bicyclo[2.2.2]octanyl]propanoic acid (BG9928) was administered orally (10 mg/kg/day) to obese ZSF1 rats (n = 10) for 24 weeks (from 20 to 44 weeks of age). Untreated ZSF1 rats (n = 9) served as controls. After 24 weeks of administration, BG9928 significantly lowered plasma triglycerides (in mg/dl: control group, 4351 ± 550; BG9928 group, 2900 ± 551) without adversely affecting plasma cholesterol or activating renin release. BG9928 significantly decreased 24-hour urinary glucose excretion (in mg/kg/day: control group, 823 ± 179; BG9928 group, 196 ± 80) and improved oral glucose tolerance, polydipsia, and polyuria. BG9928 significantly augmented left ventricular diastolic function in association with a reduction in cardiac vasculitis and cardiac necrosis. BG9928 significantly reduced 24-hour urinary protein excretion (in mg/kg/day: control group, 1702 ± 263; BG9928 group, 1076 ± 238), and this was associated with a reduction in focal segmental glomerulosclerosis, tubular atrophy, tubular dilation, and deposition of proteinaceous material in the tubules. These findings show that, in a model of HFpEF with metabolic syndrome, A1/A2B receptor inhibition improves hyperlipidemia, exerts antidiabetic actions, reduces HFpEF, improves cardiac histopathology, and affords renal protection. We conclude that chronic administration of combined A1/A2B receptor antagonists could be beneficial in patients with HFpEF, in particular those with comorbidities such as obesity, diabetes, and dyslipidemias.

Aims To evaluate the pharmacokinetics (PK) and pharmacodynamics (PD) of subcutaneous peginterferon beta-1a in patients with relapsing-remitting multiple sclerosis (RRMS) in the phase 3 ADVANCE study (n = 1512). Methods During year 1, patients were randomized (1:1:1) to placebo or peginterferon beta-1a 125 μg every 2 or 4 weeks. After year 1, patients randomized to placebo were re-randomized to 125 μg peginterferon beta-1a administered every 2 weeks or every 4 weeks for year 2. Patients randomized to peginterferon beta-1a in year 1 remained on the same dosing regimen in year 2. Intensive blood samples for PK and PD (neopterin elevation; a biomarker of pharmacological activity induced by interferon beta-1a) measurements were collected from 44 patients pre-dosing and at intervals over 240 h post-dosing at weeks 4 and 24. Sparse samples were collected from all patients after each dosing at weeks 4, 12, 24, 56 and 84. Results The PK profile of peginterferon beta-1a did not change over time or between dosing regimens. No accumulation was observed. Peak serum concentrations were reached 1–1.5 days post-dosing, with a mono-phasic decline and a median half-life of approximately 2–3 days. Dosing every 2 weeks provided approximately two-fold greater monthly cumulative area under the curve than every 4 weeks. Neopterin elevation was sustained for 10−14 days following each dose, indicating doubled cumulative duration of pharmacological activity for dosing every 2 weeks vs. every 4 weeks. Conclusions These PK/PD profiles potentially explain the enhanced efficacy of dosing every 2 weeks in patients with RRMS.

Objective: To evaluate the efficacy and safety of subcutaneous peginterferon beta-1a over 2 years in patients with relapsing–remitting multiple sclerosis in the ADVANCE study. Methods: Patients were randomized to placebo or 125 µg peginterferon beta-1a every 2 or 4 weeks. For Year 2 (Y2), patients originally randomized to placebo were re-randomized to peginterferon beta-1a every 2 weeks or every 4 weeks. Patients randomized to peginterferon beta-1a in Year 1 (Y1) remained on the same dosing regimen in Y2. Results: Compared with Y1, annualized relapse rate (ARR) was further reduced in Y2 with every 2 week dosing (Y1: 0.230 [95% CI 0.183–0.291], Y2: 0.178 [0.136–0.233]) and maintained with every 4 week dosing (Y1: 0.286 [0.231–0.355], Y2: 0.291 [0.231–0.368]). Patients starting peginterferon beta-1a from Y1 displayed improved efficacy versus patients initially assigned placebo, with reductions in ARR (every 2 weeks: 37%, pConclusions: Peginterferon beta-1a efficacy is maintained beyond 1 year, with greater effects observed with every 2 week versus every 4 week dosing, and a similar safety profile to Y1. Clinicaltrials.gov Registration Number: NCT00906399.

Peginterferon beta‐1a reduced annualized relapse rate as compared with placebo and was approved to treat multiple sclerosis patients. A population pharmacokinetic and an exposure‐efficacy model were developed to establish the quantitative relationship between pharmacokinetics and annualized relapse rate. The pharmacokinetics was well described by a 1‐compartment model with first‐order absorption and linear elimination kinetics. Body mass index was the most significant covariate that impacted both clearance and volume of distribution, which in turn impacted area under the curve and maximum serum concentration. Cumulative monthly area under the curve and annualized relapse rate were best described by a Poisson‐gamma (negative binomial) model, demonstrating that the improved efficacy of every‐2‐weeks dosing was driven by greater drug exposure. The results supported the superior efficacy of the every‐2‐week dosing regimen compared with the every‐4‐weeks dosing regimen.

Long-acting beta-agonists (LABAs) and inhaled corticosteroids administered together appear to be complementary in terms of effects on asthma control. The elements of asthma control achieved by LABAs (improved lung function) and leukotriene receptor antagonists (LTRAs; protection against exacerbations) may be complementary as well.We sought to determine whether the combination of the LTRA montelukast and the LABA salmeterol could provide an effective therapeutic strategy for asthma.In a randomized, placebo-controlled, crossover study of 192 subjects with moderate asthma, we compared the clinical efficacy of regular treatment over 14 weeks with the combination of montelukast and salmeterol to that with the combination of beclomethasone and salmeterol in moderate asthma. The primary efficacy outcome was time to treatment failure.Three months after the randomization of the last subject, the Data and Safety Monitoring Board determined that the primary research question had been answered and terminated the trial. The combination of montelukast and salmeterol was inferior to the combination of beclomethasone and salmeterol as judged by protection against asthma treatment failures (p = 0.0008), lung function (26 L/min difference in a.m. peak expiratory flow rate, p = 0.011), asthma control score (0.22 difference in Asthma Control Questionnaire score, p = 0.038), and markers of inflammation and airway reactivity.Patients with moderate asthma similar to those we studied should not substitute the combination of an LTRA and an LABA for the combination of inhaled corticosteroid and an LABA.

Objective There is a strong association between reflux and end-stage lung disease, especially idiopathic pulmonary fibrosis. The presence of reflux after lung transplantation might predispose to the development of bronchiolitis obliterans. We evaluated the risk and physiologic effect of laparoscopic fundoplication in patients on the lung transplant waiting list. Methods One hundred forty-nine patients on the lung transplant waiting list between March 2001 and January 2005 were evaluated. Nineteen were found to have a history of reflux, continued symptoms, and severe reflux by means of pH and manometric studies and underwent laparoscopic fundoplication. The postoperative course of these 19 patients, including lung function, was retrospectively reviewed. Postoperatively, the lung function of the 14 patients with idiopathic pulmonary fibrosis who underwent the laparoscopic Nissen procedure was compared with that of 31 patients with idiopathic pulmonary fibrosis on the transplant waiting list who did not undergo fundoplication. Results There were no perioperative complications and no decrease in lung function over the 15-month average follow-up. Exercise capacity remained stable, as determined on the basis of 6-minute walk distance. Patients with idiopathic pulmonary fibrosis treated with fundoplication had stable oxygen requirements, whereas control patients with idiopathic pulmonary fibrosis on the waiting list had a statistically significant deterioration in oxygen requirement. Conclusions Laparoscopic fundoplication can be performed safely in patients with end-stage lung disease awaiting lung transplantation. Overall, these patients maintained stable lung function during the follow-up period. When compared with a control group of patients with idiopathic pulmonary fibrosis not undergoing fundoplication, there was stabilization of oxygen requirement. A larger prospective trial evaluating the effect of laparoscopic fundoplication on underlying lung function in this patient population is warranted.

Small, preliminary studies have suggested that capnograms of obstructive lung disease (OD) exhibit a characteristic shape and that this shape may be correlated to changes in forced expiratory volume in 1 s (FEV(1)). We evaluated the association between capnograms and spirometry from subjects with OD with normal and restrictive lung disease (RD) subjects. The study was conducted in a prospective, nonrandomized manner using a convenience sample of 262 subjects presenting to a pulmonary function laboratory. Capnograms were recorded before pulmonary function testing. Subjects with OD had capnograms that were significantly different from normal and RD subjects. These differences were progressive, increasing with disease severity. The average take-off angle of the ascending phase for severe OD was 7.2 degrees less (95% confidence interval [CI]: 4.0, 10.4) than for normals. The average alveolar plateau elevation angle was 0.8 degrees more (95% CI: 0.14, 1.4) for moderate OD than for normals, whereas the average elevation angle was 3.6 degrees more (95% CI: 2.9, 4.3) for severe OD than for normals. Differences between OD capnograms and normal and RD capnograms, correlating to changes in FEV(1), were sufficiently large enough to suggest that the capnogram could be used to discriminate between OD and normal.

Background Subcutaneous peginterferon beta-1a provided clinical benefits at Year 1 (placebo-controlled period) of the 2-Year Phase 3 ADVANCE study in relapsing-remitting multiple sclerosis (RRMS). Here we report the effect of peginterferon beta-1a on brain magnetic resonance imaging (MRI) lesions, and no evidence of disease activity (NEDA; absence of clinical [relapses and 12-week confirmed disability progression] and MRI [gadolinium-enhancing, and new or newly-enlarging T2 hyperintense lesions] disease activity) during Year 1. Methods RRMS patients (18–65 years; Expanded Disability Status Scale score ≤5) were randomized to double-blind placebo or peginterferon beta-1a 125 μg every 2 or 4 weeks. Sensitivity analyses of last observation carried forward and composite disease activity (using minimal MRI allowance definitions) were conducted. Results 1512 patients were randomized and dosed (placebo n = 500; peginterferon beta-1a every 2 [n = 512] or 4 [n = 500] weeks). Every 2 week dosing significantly reduced, versus placebo and every 4 week dosing, the number of new or newly-enlarging T2 hyperintense lesions at Weeks 24 (by 61% and 51%, respectively) and 48 (secondary endpoint; by 67% and 54%, respectively); all p

Subjects with asthma have higher concentrations of exhaled nitric oxide (NO) than normal individuals. It has been demonstrated that in asthmatics, repeated FVC maneuvers reduce NO. Although the cause of this phenomenon is not known, it has been hypothesized that deep breaths associated with FVC maneuvers reduce exhaled NO by affecting neural sources of NO, possibly via a mechanism related to the pathobiology of asthma. To establish whether FVC maneuvers influence NO concentrations in normal individuals, we measured exhaled NO at baseline values and after FVC maneuvers performed every 15 min for 1 h in subjects without asthma. To investigate the role of deep breaths in reducing exhaled NO, we compared these results with concentrations of exhaled NO after plethysmography. Repeated FVC maneuvers over 60 min produced a decrease in NO concentrations in mixed expired gas (F(E)NO; 24.6 +/- 5.1% decrease for F(E)NO, p0. 01 versus baseline). In contrast to the results after spirometry, repeated specific airway conductance (sGaw) maneuvers do not have a significant effect on F(E)NO (p = 0.16). These results, which demonstrate that in nonasthmatic subjects FVC maneuvers-but not panting maneuvers-produce a fall in NO, suggest that the mechanism responsible for the reduction in exhaled NO after FVC maneuvers is related to volume history of the lung rather than the pathobiology of asthma.

Compared with normal individuals, subjects with asthma have elevated levels of expired nitric oxide (NO). These levels are hypothesized to reflect the degree of airway inflammation. Expired NO levels rise during the late phase of allergen challenge and decrease in asthmatics after steroid treatment. Isocapnic cold air hyperventilation (ISH) is believed to cause airway narrowing through noninflammatory mechanisms. We measured mixed expired NO in 10 individuals with atopic asthma who underwent both ISH challenge and allergen challenge, and compared these measurements with the change in expired NO that occurred after serial spirometry alone. We found that ambient NO levels affected mixed expired NO. Controlling for inspired NO, we found that repeated spirometry alone produced a significant fall in mixed expired NO (p < 0.01) that was maximal after 30 min (36.6 +/- 8.5% fall). After allergen and ISH challenges, expired NO was elevated relative to levels after repeated spirometry (p < 0.01 and p = 0.065, respectively). In addition, we found that prechallenge expired NO levels were significantly correlated with the magnitude of the late fall in FEV1 following allergen challenge (r = 0.80, p < 0.01). These data demonstrate that repeated spirometry results in reduced mixed expired NO and suggest that both ISH and allergen-induced bronchoconstriction share pathobiologic mechanisms that produce increases in mixed expired NO.

Background The ability to self-inject in patients with multiple sclerosis (MS) has been associated with a reduced risk of missed injections and drug discontinuation, and a beneficial effect on patients' independence. However, injection anxiety, needle phobia and disease-related disability are major barriers to a patient's ability to self-administer treatment. Use of an autoinjector may improve patients' ability to self-inject. This study evaluated the safe and effective use of Avonex Pen™ (prefilled pen), a single use autoinjector, for intramuscular delivery of interferon beta-1a (IM IFNβ-1a, Avonex) in MS patients. Methods This was a Phase IIIb, open-label, single-country, multicenter trial in MS patients currently using IM IFNβ-1a prefilled syringes. Patients received weekly 30 mcg IM IFNβ-1a treatment over 4 weeks. On Day 1, patients self-administered IM IFNβ-1a using a prefilled syringe at the clinic. On Day 8, patients received training on the prefilled pen and self-administered IM IFNβ-1a using the device. On Day 15, patients self-administered IM IFNβ-1a at home using the prefilled pen. A final injection occurred at the clinic on Day 22 when patients self-administered IM IFNβ-1a using the prefilled pen while clinic staff observed and completed a detailed questionnaire documenting patients' ability to self-inject with the device. Serum neopterin levels were evaluated pre and post-injection on Days 1 and 8. Adverse events were monitored throughout. Results Seventy-one (96%) patients completed the study. The overall success rate in safely and effectively using the prefilled pen was 89%. No device malfunctions occurred. One unsuccessful administration occurred at Day 22 due to patient error; no patient injury resulted. Patients gave the prefilled pen high ratings (8.7-9.3) on a 10-point scale for ease of use (0 = extremely difficult, 10 = extremely easy). Ninety-four percent of patients preferred the prefilled pen over the prefilled syringe. Induction of serum neopterin levels, serving as a biomarker for type 1 interferon action, was similar to that of the prefilled syringe. The prefilled pen demonstrated a safety profile comparable to the prefilled syringe. Conclusions The prefilled pen is a safe and effective device for administration of IM IFNβ-1a and represents an alternative method for self-injection for MS patients using this therapy. Trial registration This study is registered at clinicaltrials.gov, identifier: NCT00828204

Although guidelines recommend anti-inflammatory therapy for persistent asthma, recent studies suggest that 25% to 35% of patients with asthma may not improve lung function with inhaled corticosteroids.To evaluate potential biomarkers of predicting short-term (6-week) response to inhaled corticosteroid with subsequent evaluation of responders and nonresponders to asthma control over a longer interval (16 additional weeks).Eighty-three subjects with asthma off steroid were enrolled in this multicenter study. Biomarkers and asthma characteristics were evaluated as predictors of inhaled corticosteroid response over a 6-week trial for changes in FEV(1) and methacholine PC(20). After this, an additional 4-month trial evaluated asthma control.Although multiple baseline predictors had significant correlations with improvements for short-term inhaled steroid success, the only strong correlations (ror= +/- 0.6) were albuterol reversibility (r = 0.83; P.001), FEV(1)/forced vital capacity (r = -0.75; P.001), and FEV(1) % predicted (r = -0.71; P.001). Dividing the subjects in the short-term inhaled steroid trial into responders (5% FEV(1) improvement) and nonresponders (or=5%) determined the longer-term need for steroids. For the nonresponders, asthma control remained unchanged whether inhaled corticosteroids were continued or were substituted with a placebo (P = .99). The good short-term responders maintained asthma control longer-term only if maintained on inhaled steroids (P = .007).The short-term response to inhaled corticosteroids with regard to FEV(1) improvement predicts long-term asthma control.The decision to use long-term inhaled steroids could be based on a short-term trial. Different therapeutic strategies would need to be established for nonresponders.

Rationale: Several studies suggest that patients with asthma who are homozygous for arginine at the 16th position of the β2-adrenergic receptor may not benefit from short-acting β-agonists. Objectives: We investigated whether such genotype-specific effects occur when patients are treated with long-acting β-agonists and whether such effects are modified by concurrent inhaled corticosteroid (ICS) use. Methods: We compared salmeterol response in patients with asthma homozygous for arginine at B16 (B16Arg/Arg) with those homozygous for glycine at B16 (B16Gly/Gly) in two separate cohorts. In the first, subjects were randomized to regular therapy with salmeterol while simultaneously discontinuing ICS therapy. In the second, subjects were randomized to regular therapy with salmeterol while continuing concomitant ICS. Results: In both trials, B16Arg/Arg subjects did not benefit compared with B16Gly/Gly subjects after salmeterol was initiated. In the first cohort, compared with placebo, the addition of salmeterol was associated with a 51.4 L/min lower A.M. peak expiratory flow (PEF; p = 0.005) in B16Arg/Arg subjects(salmeterol, n = 12; placebo, n = 5) as compared with B16Gly/Gly subjects (salmeterol, n = 13; placebo, n = 13). In the second cohort, B16Arg/Arg subjects treated with salmeterol and ICS concurrently (n = 8) had a lower A.M. PEF (36.8 L/min difference, p = 0.048) than B16Gly/Gly subjects (n = 22) treated with the same regimen. In addition, B16 Arg/Arg subjects in the second cohort had lower FEV1 (0.42 L, p = 0.003), increased symptom scores (0.2 units, p = 0.034), and increased albuterol rescue use (0.95 puffs/d, p = 0.004) compared with B16Gly/Gly subjects. Conclusions: Relative to B16Gly/Gly patients with asthma, B16Arg/Arg patients with asthma may have an impaired therapeutic response to salmeterol in either the absence or presence of concurrent ICS use. Investigation of alternate treatment strategies may benefit this group.

Mind/body practices that elicit the relaxation response (RR) are currently practiced by over 30% of American adults. RR elicitation reduces volumetric oxygen consumption (VO(2)) from rest and counteracts the effects of stress, although the mechanisms mediating the RR remain unknown. This study was designed to investigate whether RR elicitation is mediated by nitric oxide (NO). We developed a method to quantify depth of RR using change in VO(2) (slope) during RR elicitation. We evaluated whether depth of RR elicitation was correlated with changes in NO, as measured by percentage changes in fractional exhaled nitric oxide (F(E)NO).We conducted a randomized, controlled trial, in which 46 subjects were randomized to either 8-weeks of RR training using audiotapes (n=34) or 8-weeks of exposure to a control condition--receiving health-education by audiotapes (n=12). Prior to randomization, VO(2) and F(E)NO were measured while subjects listened to a control audiotape. Eight weeks later, VO(2) and F(E)NO were measured while the RR group listened to a RR-eliciting audiotape and the control group listened to a control audiotape.Prior to receiving any training, there was no association between VO(2) slope and F(E)NO. After training, there was an inverse correlation between VO(2) slope and F(E)NO in the RR group (r = -0.41, P=0.037, n=26), but not in the control group (r=0.12, P=0.78, n=8).Depth of RR elicitation was associated with increased concentrations of F(E)NO after RR training. The RR may be mediated by NO helping to explain its clinical effects in stress-related disorders.

Measurement of the fraction of exhaled nitric oxide (FENO) has been proposed as a noninvasive assessment of asthmatic airway inflammation. The influence of the expiratory flow rate during the collection maneuver on the ability of FENO to discriminate healthy subjects from those with asthma is unknown. We compared online and offline measurement of FENO at different flow rates. FENO was collected with expiratory flows of 50-500 ml/second in 34 patients with asthma (PC(20) of less than 8 mg/ml) and 28 healthy subjects (PC(20) of more than 10 mg/ml) using offline collection techniques. In a subgroup of 18 individuals with asthma and 17 healthy subjects, we additionally measured FENO at multiple expiratory flow rates (47-250 ml/second) using online methods. FENO fell with an increasing expiratory flow rate; FENO was higher in subjects with asthma as compared with healthy subjects at each flow rate studied with both techniques (p0.001). Receiver operating characteristic (ROC) curves for the diagnosis of asthma indicated that FENO is a robust discriminator between individuals with asthma and healthy subjects (area under the ROC curves 0.79 +/- 0.06 to 0.86 +/- 0.06, p for significant discrimination0.0001). Neither expiratory flow rate nor collection technique (online versus offline) significantly altered this discriminatory capacity (area under the ROC curves = 0.84 +/- 0.07 with the slowest online method versus 0.80 +/- 0.07 with the fastest offline method, p = 0.46). These data indicate that the choice of expiratory flow rate and collection method can be based on practicality and patient comfort without compromising the utility of this test for asthma.

An increased concentration of nitric oxide (NO) in exhaled air (FENO) is now recognized as a critical component of the asthmatic phenotype. When we identified patients with asthma on the basis of a standard case definition alone, we found that they were remarkably heterogeneous with respect to their FENO. However, when we included genotype at a prominent asthma candidate gene (i.e., NOS1) in the case definition, and determined the number of AAT repeats in intron 20, we identified a remarkably homogeneous cohort of patients with respect to FENO. Both mean FENO (p = 0.00008) and variability around the mean (p = 0.000002) were significantly lower in asthmatic individuals with a high number (or = 12) of AAT repeats at this locus than in those with fewer repeats. These data provide a biologically tenable link between genotype at a candidate gene in a region of linkage, NOS1, and an important component of the asthmatic phenotype, FENO. We show that addition of NOS1 genotype to the case definition of asthma allows the identification of a uniform cohort of patients, with respect to FENO, that would have been indistinguishable by other physiologic criteria. Our isolation of this homogeneous cohort of patients ties together the well-established associations among asthma, increased concentrations of NO in the exhaled air of asthmatic individuals, and variations of trinucleotide repeat sequences as identified in several neurologic conditions.

Nitric oxide (NO) is a molecular gas that can be recovered in higher levels from the exhaled gas of subjects with asthma than from subjects without asthma. However, the precise mechanisms responsible of promoting increased fraction of expired nitric oxide (FE(NO)) in asthma are unknown. As leukotriene antagonism has been shown to reduce FE(NO) in patients with asthma, we hypothesized that leukotrienes mediate the increased FE(NO) encountered in this condition. Furthermore, because leukotriene antagonism stabilizes serum eosinophil markers during reductions in inhaled corticosteroid doses, and FE(NO) has been shown to correlate with sputum eosinophils in asthma, we reasoned that the effect of leukotrienes on FE(NO) might be mediated by eosinophils recruited to the airway by leukotrienes. To test this hypothesis, we performed methacholine and leukotriene (LT) E(4) bronchoprovocation challenges in 16 subjects with atopic asthma and measured FE(NO) and sputum differential counts before and after bronchoprovocation. We then compared FE(NO) in the seven subjects who developed increased sputum eosinophils following LTE(4) inhalation with values measured after methacholine inhalation in these seven subjects. Following LTE(4) inhalation, eosinophils rose from 4.01 +/- 0.89% pre-LTE(4) to 8.33 +/- 1.52% post-LTE(4). The mean change in sputum eosinophils from baseline after LTE(4) inhalation was larger than that after methacholine inhalation (+4.31 +/- 1.25% versus -1.14 +/- 0.93%). After LTE(4) inhalation, FE(NO) levels did not differ from prechallenge baseline or from levels following methacholine inhalation (ANOVA p > 0.05). These data indicate that neither LTE(4) nor recruitment of eosinophils into the airway by LTE(4) is a sufficient stimulus to acutely increase FE(NO) in subjects with asthma.