Theory of chain walking catalysis: From disordered dendrimers to dendritic bottle-brushes.

The chain walking (CW) polymerization technique has the unique property of a movable catalyst synthesizing its own path by creating branch-on-branch structures. By successive attachment of monomers, the resulting architecture ranges from dendritic to linear growth depending on the walking rate, which is defined by the ratio of walking steps and reaction events of the catalyst. The transition regime is characterized by local dendritic sub-structures (dendritic blobs) and a global linear chain feature forming a dendritic bottle-brush. A scaling model for structures obtained by CW catalysis is presented and validated by computer simulation relating the extensions of CW structures to the catalyst's walking ability. The limiting case of linear (low walking rate) and dendritic growth (high walking rate) is recovered, and the latter is shown to bear analogies to the Barabási-Albert graph and Bernoulli growth random walk. We could quantify the size of the dendritic blob as a function of the walking rate by using spectral properties of the connectivity matrix of the simulated macromolecules. This allows us to fit the numerical constants in the scaling approach. We predict that independent of the underlying chemical process, all CW polymerization syntheses involving a highly mobile catalyst ultimately result in bottle-brush structures whose properties depend on a unique parameter: the walking rate.

[The first biologic for rheumatoid arthritis: factors influencing the therapeutic decision]. / Das erste Biologikum bei rheumatoider Arthritis: Einflussfaktoren auf die Therapieentscheidung.

BACKGROUND AND AIMS: Biologics (disease modifying antirheumatic drugs, bDMARD) have been in use in Germany for the treatment of rheumatoid arthritis (RA) since 2001, usually after failure of at least one conventional synthetic (cs)DMARD. We analyzed temporal changes in factors that influence the decision for either a first bDMARD or a further csDMARD. MATERIAL AND METHODS: We analyzed data from 9513 bDMARD-naive RA patients in the German biologics register RABBIT who switched to a new therapy. For three recruitment periods (2001-2003, 2004-2006 and 2009-2015) factors influencing the therapeutic decision were analyzed by means of machine learning methods and logistic regression analysis. RESULTS: In all recruitment periods the number of previous csDMARDs, high dosages of glucocorticoids (>7.5 mg/day) and a higher DAS28 (>5.1) were significantly associated with the decision for a first bDMARD. Over time, the chance of receiving a bDMARD increased in patients with moderate disease activity, moderate glucocorticoid dosages (5-7.5 mg/day) and those with comorbidities, such as congestive heart failure or prior malignancy. Men had a higher chance of receiving a bDMARD than women only in the first recruitment period. Private health insurance, high education and gainful employment were significantly associated with more frequent prescription of bDMARDs in all recruitment periods. DISCUSSION: The time-dependent changes in the impact of disease activity, concomitant drugs, gender and comorbidity on the prescription of bDMARDs mirror the increasing therapeutic options and the growing experience in the application of the new substances in patients at higher risk. The influence of demographic and social factors may reflect safety concerns in patients at increased risk of adverse events but also the need to economize drug costs..

Two universality classes for random hyperbranched polymers.

We grow AB2 random hyperbranched polymer structures in different ways and using different simulation methods. In particular we use a method of ad hoc construction of the connectivity matrix and the bond fluctuation model on a 3D lattice. We show that hyperbranched polymers split into two universality classes depending on the growth process. For a "slow growth" (SG) process where monomers are added sequentially to an existing molecule which strictly avoids cluster-cluster aggregation the resulting structures share all characteristic features with regular dendrimers. For a "quick growth" (QG) process which allows for cluster-cluster aggregation we obtain structures which can be identified as random fractals. Without excluded volume interactions the SG model displays a logarithmic growth of the radius of gyration with respect to the degree of polymerization while the QG model displays a power law behavior with an exponent of 1/4. By analyzing the spectral properties of the connectivity matrix we confirm the behavior of dendritic structures for the SG model and the corresponding fractal properties in the QG case. A mean field model is developed which explains the extension of the hyperbranched polymers in an athermal solvent for both cases. While the radius of gyration of the QG model shows a power-law behavior with the exponent value close to 4/5, the corresponding result for the SG model is a mixed logarithmic-power-law behavior. These different behaviors are confirmed by simulations using the bond fluctuation model. Our studies indicate that random sequential growth according to our SG model can be an alternative to the synthesis of perfect dendrimers.

Fluctuation driven height reduction of crosslinked polymer brushes: a Monte Carlo study.

We study the changes in the conformations of brushes upon the addition of crosslinks between the chains using the bond fluctuation model. The Flory-Rehner model applied to uniaxially swollen networks predicts a collapse for large degrees of crosslinking q proportional to q(-1∕3) in disagreement with our simulation data. We show that the height reduction of the brushes is driven by monomer fluctuations in a direction perpendicular to the grafting plane and not due to network elasticity. We observe that the impact of crosslinking is different for reactions between monomers of the same or on different chains. If the length reduction of the effective chain length due to both types of reactions is accounted for in a function ß(q), the height of the brush can be derived from a Flory approach for the equilibrium brush height leading to H(q) ≈ Hbß(q)(1∕3), whereby Hb denotes the height of the non-crosslinked brush.

Comparative effectiveness of tumour necrosis factor alpha inhibitors in combination with either methotrexate or leflunomide.

OBJECTIVE: The objective of this study was to compare the effectiveness of a combination of tumour necrosis factor alpha (TNFalpha) inhibitors with either methotrexate or leflunomide in the treatment of patients with rheumatoid arthritis in a real-world setting. METHODS: Data from 1769 outpatients enrolled in the German biologics register RABBIT who were treated with one of the TNFalpha inhibitors adalimumab, etanercept, or infliximab in combination with either methotrexate (n = 1375) or leflunomide (n = 394) were included in the analysis. Clinical status including disease activity as well as treatment data were documented by the treating rheumatologist at baseline and at 3, 6, 12, 18, 24, 30 and 36 months of follow-up. RESULTS: Patients treated with a combination of biologics with leflunomide had significantly higher baseline disease activity than those treated with methotrexate. The highest disease activity was found for patients treated with the combination infliximab/leflunomide. After 36 months, the discontinuation rates were 46.3%, 51.3% and 61.5% for combinations of etanercept, adalimumab and infliximab with methotrexate and 53.4%, 63.1% and 67.1% for combinations with leflunomide, respectively. European League Against Rheumatism response rates after 24 months ranged from 74% to 81% for combinations with methotrexate and 72% to 81% for combinations with leflunomide. CONCLUSION: The current clinical practice is to use methotrexate as a first choice for the combination with TNFalpha antagonists. In a number of patients methotrexate has to be replaced by another disease-modifying antirheumatic drug. Our data support the view that leflunomide is a useful alternative if methotrexate is contraindicated.

Comparison of the effects of intravenous and oral montelukast on airway function: a double blind, placebo controlled, three period, crossover study in asthmatic patients.

BACKGROUND: Montelukast, a leukotriene receptor antagonist, improves parameters of asthma control including forced expiratory volume in one second (FEV(1)) when given orally to patients aged six years or older. This study was undertaken to compare the effect on FEV(1) of intravenous and oral montelukast and placebo during the 24 hour period following administration. METHODS: Fifty one asthmatic patients (FEV(1) 40-80% predicted and > or =15% improvement after inhaled beta agonist) were enrolled in a double blind, single dose, three period, crossover study to receive intravenous montelukast (7 mg), oral montelukast (10 mg), or placebo in a randomised fashion. The primary end point was area under the curve (AUC)(0-24 h) of the percentage change from baseline in FEV(1). Additional end points were maximum percentage change in FEV(1) and percentage change at different time points. RESULTS: Compared with placebo, intravenous and oral montelukast significantly increased the AUC(0-24 h) (means of 20.70%, 15.72%, and 7.75% for intravenous, oral and placebo, respectively; no statistical difference between intravenous and oral). The difference in least square means from placebo for intravenous montelukast was 13.27% (95% CI 7.07 to 19.46), p<0.001 and for oral montelukast was 7.44% (95% CI 1.20 to 13.68), p = 0.020. The maximum percentage change in FEV(1) was not significantly different for intravenous and oral montelukast (difference in least square means 6.78% (95% CI -0.59 to 14.15), p = 0.071). The mean percentage change in FEV(1) for intravenous montelukast was greater than for oral montelukast within the first hour (15.02% vs 4.67% at 15 min, p< or =0.001; 18.43% vs 12.90% at one hour, p<0.001 for intravenous and oral montelukast, respectively (placebo 3.05% at 15 minutes, 7.33% at one hour). Intravenous and oral montelukast were similar to placebo in the frequency of adverse events. CONCLUSIONS: The onset of action for intravenous montelukast was faster than for oral montelukast and the improvement in airway function lasted over the 24 hour observation period for both treatments. Although not well understood, there was a trend toward a greater improvement in FEV(1) with intravenous than with oral montelukast. These findings suggest that leukotriene receptor antagonists should be investigated as a treatment for acute severe asthma.

Proventil HFA prevents exercise-induced bronchoconstriction in children.

Short-acting inhaled beta2-agonists used just prior to exercise are an effective method for preventing exercise-induced bronchoconstriction (EIB) in children. This was a randomized, single-blind, placebo-controlled, four-period crossover study that compared the effectiveness of albuterol formulated in hydrofluoroalkane-134a (HFA) to albuterol formulated in chlorofluorocarbons (CFCs) and to placebo in protecting asthmatic children age 6-11 from EIB. Patients self-administered either HFA albuterol, two different CFC albuterol products, or placebo 30 min prior to exercise challenge. Spirometry was performed predose and 5, 10, 15, 30, 45, 60, 75, and 90 min after the exercise challenge was completed. The smallest percent change from the predose forced expiratory volume in 1 sec (FEV1) after exercise challenge was similar for the three active treatments, and each of the active treatments was significantly better than placebo. Each active treatment had significantly fewer patients unprotected from EIB (unprotected defined as having >20% fall in FEV1 after exercise challenge) than placebo. Changes in heart rate, blood pressure and electrocardiogram (ECG) intervals were similar for the three active treatments following exercise. HFA albuterol is as effective as albuterol products formulated in CFCs and more effective than placebo in protecting asthmatic children from EIB.

Therapeutic equivalence of Spiros dry powder inhaler and Ventolin metered dose inhaler. A bioassay using methacholine.

Because chlorofluorocarbons (CFCs) contribute to depletion of stratospheric ozone, CFC-containing metered-dose inhalers (MDIs) such as Ventolin and Proventil are being phased out of production. In terms of delivery of albuterol to the lungs, we compared an alternative delivery system, the Spiros dry-powder inhaler (DPI), with Ventolin, using a methacholine challenge-based clinical bioassay. Twenty-four adults and adolescents with asthma completed this double-blind, four-period crossover study. Doses evaluated were one and three actuations each of Spiros and Ventolin (90- and 270-microgram albuterol base). A methacholine challenge (Cockcroft method) was initiated 3 h before and 0.25 h after albuterol. Predose PC(20)FEV(1) values were not significantly different between study days. Postdose PC(20)FEV(1) results met standard bioassay study validity criteria: i.e., a significant dose-response relationship was present (p = 0.0002); tests for deviation from parallelism and overlap of dose-response curves were nonsignificant (p = 0.08, 0.69). By using Finney 2-by-2 bioassay analysis, we estimate that each Spiros actuation delivers 1.12 times as much albuterol to the airways as one Ventolin actuation (90% confidence interval, 0.68 to 1.94). There were no significant differences in markers of systemic effects (vital signs, potassium, and blood glucose concentrations). We conclude that Spiros and Ventolin inhalers deliver comparable quantities of albuterol to the airways.

Dose-proportional pharmacokinetics of budesonide inhaled via Turbuhaler.

AIMS: The present pharmacokinetic study was undertaken to determine the dose proportionality of three different doses of budesonide-400 microg, 800 microg or 1600 microg administered twice daily by a dry-powder inhaler (Turbuhaler ) in adult patients with mild asthma. METHODS: A total of 38 patients received budesonide by inhalation, 13 received 400 microg twice daily, 12 received 800 microg twice daily and 13 received 1600 microg twice daily. Mean FEV1 at inclusion was 3.4, 4.0 and 3.9 l min-1 in the three groups, respectively. Blood samples were taken after a single dose, and after 3 weeks of daily treatment, for pharmacokinetic evaluation. Plasma concentrations of budesonide were determined by liquid chromatography plus mass spectrometry. RESULTS: Eleven evaluable patients remained in each dose group. Mean time to peak budesonide plasma concentration (tmax ) was short (0.28-0.40 h) and did not differ between treatment groups. Budesonide concentrations declined rapidly thereafter, indicating efficient pulmonary absorption and rapid elimination with a half-life of approximately 3 h. Cmax was 1. 4(2.0) nmol l-1 (single (repeated) doses), 2.6(3.6) nmol l-1 and 5. 4(6.4) nmol l-1 after 400, 800 and 1600 microg twice daily, respectively. The corresponding results for the area under the plasma concentration vs time curve (AUC) were 271(325), 490(628) and 915(1096) nmol l-1 min. Ninety percent confidence intervals for pairwise dose-normalized Cmax and AUC comparisons between groups were large but contained unity in all cases, thus indicating dose-proportional pharmacokinetics. Regression on analysis supported these findings. Mean AUC after repeated doses (AUC(0,12 h,RD)) was on average 23% higher than the mean AUC after single doses (AUC(0, infinity,SD)(P=0.04) with no significant differences between doses, indicating slight accumulation following bid dosing. CONCLUSIONS: In this relatively small study, budesonide inhaled via Turbuhaler appeared to have dose-proportional pharmacokinetics, both within and above the clinically recommended dose range for asthmatic patients.

A dose-ranging study of mometasone furoate aqueous nasal spray in children with seasonal allergic rhinitis.

BACKGROUND: The efficacy and safety of mometasone furoate aqueous nasal spray (MFNS; Nasonex) 200 microg once daily for the treatment and prophylaxis of seasonal allergic rhinitis (SAR) and treatment of perennial rhinitis have been demonstrated in adults. However, the dose response of MFNS in pediatric patients has not yet been characterized. OBJECTIVE: This study was conducted to determine the dose-response relationship of 3 different doses of MFNS in a pediatric population. METHODS: This was a multicenter, double-blind, active- and placebo-controlled study of 679 children 6 to 11 years of age with histories of SAR and documented positive skin test responses. Patients were randomized to one of the following treatment groups for 4 weeks: MFNS 25 microgram once daily, MFNS 100 microgram once daily, MFNS 200 microgram once daily, beclomethasone dipropionate 84 microgram twice daily (168 microgram/day), or placebo. Physician evaluations were performed at days 4, 8, 15, and 29, and patient evaluations were analyzed for days 1 to 15 and 16 to 29. RESULTS: The mean reduction from baseline in physician-evaluated total nasal symptom scores at day 8 (the primary efficacy variable) was significantly greater in the MFNS and beclomethasone dipropionate groups than in the placebo group (P

Adrenal effects and pharmacokinetics of CFC-free beclomethasone dipropionate: a 14-day dose-response study.

Since equivalent efficacy is achieved with lower doses of the reformulated beclomethasone dipropionate in the chlorofluorocarbon (CFC)-free propellant HFA-134a (HFA) than with the original CFC-beclomethasone dipropionate formulation, it is possible the HFA-beclomethasone dipropionate may have less safety concerns than the CFC formulation. Despite its chronic use, the steady-state pharmacokinetics of beclomethasone dipropionate has never been studied before. This double-blind study examined adrenal effects and pharmacokinetics after 14 days of dosing with HFA-beclomethasone dipropionate. Forty-three steroid-naïve asthmatic patients were randomised into 5 parallel groups and dosed every 12 h for 14 days with: HFA-placebo; 200, 400 or 800 microg day(-1) HFA-beclomethasone dipropionate; or 800 microg day(-1) CFC-beclomethasone dipropionate. After two weeks of dosing, the 24-h urinary free cortisol of all but one patient remained within the normal range, showing that all doses were well tolerated from a systemic safety perspective. The active HFA-beclomethasone dipropionate treatment groups showed a dose-related fall in 24-h urinary free cortisol. Total-beclomethasone (beclomethasone dipropionate and metabolites) pharmacokinetics after either the first dose of HFA-beclomethasone dipropionate or CFC-beclomethasone dipropionate were not substantially affected by subsequent doses. The extent of drug absorption from 800 microg day(-1) HFA-beclomethasone dipropionate and CFC-beclomethasone dipropionate was in the ratio of 1.7 : 1. A non-linear correlation between 24-h urinary free cortisol and the pharmacokinetic parameters was observed, reflecting smaller changes in 24-h urinary free cortisol than in pharmacokinetics as the dose was increased. No clinically meaningful change in the pharmacokinetics of beclomethasone dipropionate plus metabolites was seen on multiple dosing. The greater systemic availability of HFA-beclomethasone dipropionate was still associated with adrenal effects comparable with that of the CFC formulation at the same dose.

Ipratropium bromide nasal spray 0.03% and beclomethasone nasal spray alone and in combination for the treatment of rhinorrhea in perennial rhinitis.

BACKGROUND: Perennial rhinitis is a common condition that affects up to 10% to 20% of the population. Multiple agents are frequently administered since no single agent provides complete relief. Studies assessing the benefit/risk of combined therapy are important especially for newly approved agents such as ipratropium bromide nasal spray 0.03%, a topical anticholinergic agent, approved specifically for the treatment of rhinorrhea in allergic and non-allergic perennial rhinitis. OBJECTIVE: To compare the efficacy and safety of the combined use of ipratropium bromide nasal spray 0.03% (42 microg per nostril tid) and beclomethasone dipropionate nasal spray (84 microg per nostril bid) against that of either active agent alone for the treatment of rhinorrhea. DESIGN: Multicenter, 6-week, double-blind, randomized active- and placebo-controlled, parallel trial. SETTING: Allergist and general practitioner clinical practices. PATIENTS: Five hundred thirty-three patients with perennial rhinitis (279 allergic and 274 non-allergic), 8 to 75 years of age, who had at least a mild degree of severity of rhinorrhea for a minimum of 2 hours per day during the 1 week screening period as well as congestion or sneezing also of at least mild severity. INTERVENTION: Either (1) ipratropium bromide nasal spray 0.03% (42 microg per nostril tid) plus beclomethasone dipropionate nasal spray (84 microg per nostril bid), (2) ipratropium bromide nasal spray 0.03% (42 microg per nostril tid) alone, (3) beclomethasone dipropionate nasal spray (84 microg per nostril bid) alone, or (4) vehicle [matching placebo nasal spray for the ipratropium bromide (2 sprays per nostril tid)] or beclomethasone dipropionate (2 sprays per nostril bid). MAIN OUTCOME MEASURE: Severity and duration of rhinorrhea, and patient and physician global assessment of control of rhinorrhea. RESULTS: Ipratropium bromide nasal spray plus beclomethasone nasal spray was more effective than either active agent alone or vehicle in reducing the average severity and duration of rhinorrhea during 4 weeks of treatment. The advantage of ipratropium bromide plus beclomethasone nasal spray was evident by the first day of combined treatment and continued throughout the 2-week treatment period. Ipratropium bromide nasal spray had a faster onset of action during the first week of treatment and reduced the duration of rhinorrhea more than beclomethasone. Beclomethasone nasal spray was more effective in reducing the severity of congestion and sneezing than ipratropium. In patients who had not responded well to a nasal steroid prior to participation in the study based on a questionnaire administered at screening, ipratropium bromide was as effective in the steroid non-responders as steroid responders, whereas beclomethasone was more effective in steroid responders. Combined active therapy was well tolerated with no increase in adverse events over that seen previously with ipratropium bromide or beclomethasone nasal spray alone. CONCLUSIONS: The combined use of ipratropium bromide nasal spray with beclomethasone dipropionate nasal spray is more effective than either active agent for the treatment of rhinorrhea, and does not result in a potentiation of adverse drug reactions. Ipratropium bromide nasal spray 0.03% alone should be considered in patients for whom rhinorrhea is the primary symptom, and its use in combination with a nasal steroid should be considered in patients where rhinorrhea is one of the predominant symptoms, or in patients with rhinorrhea not fully responsive to other therapy.

Correlation of cat-hair (Fel d1) prick skin test to airway response using a live-cat-room challenge model.

The purpose of this study was to document the relationship between prick skin test, airway, and common allergy symptom responses to natural cat exposure. Twenty-nine volunteers with a history of cat-hair allergy and asthma were recruited. Subjects had spirometry and prick skin test with Fel d1 on Visit 1. On Visit 2, subjects had a live-cat-room challenge with airway responses and allergy symptoms monitored. All 29 subjects had a positive skin test (wheal > or = 4 mm), but only 12 (41%) had a positive airway response (fall in FEV1 > or = 15%). There was no significant correlation between the fall in FEV1 and wheal size. All symptom scores increased significantly from baseline, but the change was not significantly related to wheal size. In summary, prick skin test response is not a good predictor of airway response or changes in allergy symptoms using the live-cat-room challenge model.

Montelukast once daily inhibits exercise-induced bronchoconstriction in 6- to 14-year-old children with asthma.

OBJECTIVE: To determine whether montelukast, a leukotriene receptor antagonist, attenuates exercise-induced bronchoconstriction (EIB) in 6- to 14-year-old children with asthma. STUDY DESIGN: Double-blind, multicenter, 2-period crossover study. Children (n = 27) with forced expiratory volume in 1 second (FEV1) > or =70% of the predicted value and a fall in FEV1 > or =20% after exercise on 2 occasions. Patients received montelukast (5-mg chewable tablet) or placebo once daily in the evening for 2 days in crossover fashion (at least 4 days between treatment periods). Standardized exercise challenges were performed 20 to 24 hours after the last dose in each period. End points included area above the postexercise percent fall in FEV1 versus time curve (AAC0-60 min), maximum percent fall in FEV1 from pre-exercise baseline, and time to recovery of FEV1 to within 5% of pre-exercise baseline. RESULTS: Montelukast significantly reduced AAC0-60 min (265 vs 590% x min for montelukast and placebo, respectively, P < or = .05; approximately 59% protection relative to placebo) and the maximum percent fall (18% vs 26% for montelukast and placebo, respectively, P < or = .05). Montelukast treatment resulted in a shorter time to recovery (18 vs 28 minutes for montelukast and placebo, respectively, P = .079). CONCLUSIONS: Montelukast attenuates EIB at the end of the dosing interval in 6- to 14-year-old children with asthma.

Effect of fluticasone propionate aqueous nasal spray versus oral prednisone on the hypothalamic-pituitary-adrenal axis.

BACKGROUND: Fluticasone propionate is a glucocorticoid with negligible oral bioavailability and very low intranasal bioavailability that is used as an intranasal spray for the treatment of rhinitis. OBJECTIVE: The purpose of this study was to evaluate the hypothalamic-pituitary-adrenal (HPA)axis effects of fluticasone propionate aqueous nasal spray (FP ANS) compared with oral prednisone and placebo by using a 6-hour cosyntropin infusion test. METHODS: In a 4-week, randomized, double-blind, double-dummy, placebo-controlled parallel-group study, 105 adult patients with allergic rhinitis were randomly assigned to receive FP ANS 200 microg once daily, FP ANS 400 microg twice daily, oral prednisone 7.5 mg once daily, oral prednisone 15 mg once daily, or placebo. HPA-axis function was assessed at the screening visit and after 4 weeks of treatment by measuring morning plasma cortisol concentrations and poststimulation concentrations of plasma and urinary cortisol. RESULTS: There was no evidence of altered HPA-axis response to cosyntropin by the end of treatment with FP ANS 200 microg once daily or FP ANS 400 microg twice daily when compared with placebo. In contrast, 4 weeks of treatment with oral prednisone 7.5 or 15 mg once daily was associated with significant (p < 0.05 vs placebo) reduction in HPA-axis function, as evidenced by lower plasma cortisol concentrations (area under the plasma concentration-time curve and peak concentrations) after cosyntropin stimulation and reduced mean 24-hour urinary cortisol excretion. FP ANS 400 microg twice daily and both prednisone regimens were associated with a significant (p < 0.05 vs placebo) reduction in mean morning plasma cortisol concentrations. CONCLUSION: These results indicate that a 4-week course of FP ANS at four times the recommended dose does not suppress adrenal function in response to a 6-hour cosyntropin stimulation test.

Montelukast, a leukotriene-receptor antagonist, for the treatment of mild asthma and exercise-induced bronchoconstriction.

BACKGROUND: Patients with mild asthma frequently have only exercise-induced bronchoconstriction, a symptom of inadequate control of asthma. We evaluated the ability of montelukast, a leukotriene-receptor antagonist, to protect such patients against exercise-induced bronchoconstriction. METHODS: We randomly assigned 110 patients (age, 15 to 45 years) with mild asthma and a decrease in the forced expiratory volume in one second (FEV1) of at least 20 percent after exercise on two occasions during a placebo run-in period to receive 10 mg of montelukast (54 patients) or placebo (56 patients) once daily at bedtime for 12 weeks in a double-blind study. Treatment was followed by a two-week, single-blind washout period during which all patients received placebo. Exercise challenges were performed at base line; 20 to 24 hours after dosing at weeks 4, 8, and 12; and at the end of the washout period. The primary end point was the area under the curve for FEV1 (expressed as the percent change from base-line values) in the first 60 minutes after exercise. This measure summarized the extent and duration of bronchoconstriction after exercise. RESULTS: At 12 weeks, montelukast therapy offered significantly greater protection against exercise-induced bronchoconstriction than placebo therapy (expressed as the percentage of inhibition of the end points), as evidenced by the improvement in the area under the FEV1 curve (degree of inhibition, 47.4 percent; P=0.002). Montelukast therapy was also associated with a significant improvement in the maximal decrease in FEV1 after exercise (P=0.003) and the time from the maximal decrease in FEV1 to the return of lung function to within 5 percent of pre-exercise values (P=0.04). The differences between groups in the various measures of lung function were similar at 4, 8, and 12 weeks; there was no evidence of rebound worsening of lung function in the montelukast group after the washout period. After 12 weeks of treatment, patients in the montelukast group were more likely to rate their asthma control as better and less likely to require rescue therapy with a beta-agonist during or after exercise challenge. The rates of adverse events were similar in the two groups. CONCLUSIONS: As compared with placebo, once-daily treatment with montelukast provided significant protection against exercise-induced asthma over a 12-week period. Tolerance to the medication and rebound worsening of lung function after discontinuation of treatment were not seen.

Montelukast, a once-daily leukotriene receptor antagonist, in the treatment of chronic asthma: a multicenter, randomized, double-blind trial. Montelukast Clinical Research Study Group.

OBJECTIVES: To determine the clinical effect of oral montelukast sodium, a leukotriene receptor antagonist, in asthmatic patients aged 15 years or more. DESIGN: Randomized, multicenter, double-blind, placebo-controlled, parallel-group study. A 2-week, single-blind, placebo run-in period was followed by a 12-week, double-blind treatment period (montelukast sodium, 10 mg, or matching placebo, once daily at bedtime) and a 3-week, double-blind, washout period. SETTING/PATIENTS: Fifty clinical centers randomly allocated 681 patients with chronic, stable asthma to receive placebo or montelukast after demonstrating a forced expiratory volume in 1 second 50% to 85% of the predicted value, at least a 15% improvement in forced expiratory volume in 1 second (absolute value) after inhaled beta-agonist administration, a minimal predefined level of daytime asthma symptoms, and inhaled beta-agonist use. Twenty-three percent of the patients used concomitant inhaled corticosteroids. PRIMARY END POINTS: Forced expiratory volume in 1 second and daytime asthma symptoms. RESULTS: Montelukast improved airway obstruction (forced expiratory volume in 1 second, morning and evening peak expiratory flow rate) and patient-reported end points (daytime asthma symptoms, "as-needed" beta-agonist use, nocturnal awakenings) (P<.001 compared with placebo). Montelukast provided near-maximal effect in these end points within the first day of treatment. Tolerance and rebound worsening of asthma did not occur. Montelukast improved outcome end points, including asthma exacerbations, asthma control days (P<.001 compared with placebo), and decreased peripheral blood eosinophil counts (P<.001 compared with placebo). The incidence of adverse events and discontinuations from therapy were similar in the montelukast and placebo groups. CONCLUSIONS: Montelukast, compared with placebo, significantly improved asthma control during a 12-week treatment period. Montelukast was generally well tolerated, with an adverse event profile comparable with that of placebo.

Effects of budesonide by means of the Turbuhaler on the hypothalmic-pituitary-adrenal axis in asthmatic subjects: a dose-response study.

BACKGROUND: As a general phenomenon, corticosteroids may suppress the activity in the hypothalamic-pituitary-adrenal (HPA) axis. The adrenal stimulation test is a commonly used method to assess the relative risk of exogenous corticosteroids to induce systemic side effects. OBJECTIVES: This clinical trial was performed to assess the effects of budesonide on the HPA axis (at 800, 1600, or 3200 microg/day, given as a twice daily regimen, administered by means of the Turbuhaler) in adult patients with mild, non-steroid-dependent asthma. METHODS: Sixty-four asthmatic patients received budesonide or placebo by inhalation or 10 mg/day oral prednisone once daily as a positive control in a double-blind, double-dummy, randomized, placebo-controlled, parallel-group, multicenter study. Plasma cortisol concentration was measured to assess the effect on the HPA axis before and during a 6-hour infusion of synthetic adrenocorticotropic hormone (ACTH), cosyntropin. RESULTS: After 6 weeks of treatment, plasma cortisol concentrations after adrenal stimulation by cosyntropin infusion had fallen by 4% in the placebo group; by 13%, 11%, and 27% in the budesonide groups (800, 1600, and 3200 microg/day, respectively); and by 35% in the prednisone group. The decrease was significant only in the 3200 microg/day budesonide (p = 0.03) and prednisone (p = 0.005) groups. Over the same time period, decreases in basal plasma cortisol concentrations were 1% in the placebo group; 19%, 19%, and 34% in the three budesonide groups; and 37% in the prednisone group. Only in the prednisone group was the decrease significant (p = 0.03 vs placebo). CONCLUSIONS: In this study budesonide inhaled by means of the Turbuhaler, at doses recommended for clinical use (800 or 1600 microg/day), did not produce any statistically significant suppression of the HPA axis compared with placebo.

Tri-Nasal triamcinolone acetonide nasal spray 200 and 400 micrograms qd versus placebo and Nasacort triamcinolone acetonide nasal aerosol 440 micrograms qd in patients suffering from seasonal allergic rhinitis during the grass season.

Tri-Nasal Nasal Spray is an investigational solution of triamcinolone acetonide (TAA) currently being evaluated as a treatment for allergic rhinitis. The safety and efficacy of 200 and 400 micrograms once daily doses of Tri-Nasal Nasal Spray, an active control (440 micrograms once daily of Nasacort Nasal aerosol), and Tri-Nasal Nasal Spray placebo were compared over a 2-week treatment period in a double-blind (the Nasacort treatment was not blinded), parallel design trial. A total of 377 adult patients in 13 centers were enrolled during the grass pollen season. The primary efficacy variable was the weekly average of the SSI (Symptom Severity Index), the sum of daily nasal congestion, rhinorrhea, and sneezing severity scores from the patient diary. A total of 355 patients completed the study. All active treatments were significantly more effective than placebo in relieving nasal symptoms at each treatment week. The 400 micrograms Tri-Nasal Nasal Spray and Nasacort treatments had a rapid onset of action, demonstrating significant improvement in the SSI versus placebo by the second day of treatment. Results for the individual nasal symptoms and other secondary efficacy measures paralleled those of the primary efficacy variables. Tri-Nasal Nasal Spray and Nasacort were comparable in safety, and in treating the nonocular symptoms of seasonal allergic rhinitis.

Proventil HFA provides protection from exercise-induced bronchoconstriction comparable to proventil and ventolin.

INTRODUCTION: During the 1970s, scientists suggested that the growing use of chlorofluorocarbons (CFCs) was contributing to depletion of the stratospheric ozone layer with potentially harmful results. A committee on the ozone layer organized the preparation of the Montreal Protocol. This protocol mandated the cessation of production and use of CFCs by January 1, 1996. The primary exemption to this ban is for the use of CFCs as propellants in metered dose inhalers (MDIs) for the treatment of asthma. Suitable replacement hydrofluoroalkane (HFA) propellants, such as HFA-134a, for use in MDIs have been identified. Albuterol, a selective beta-adrenergic agonist, currently widely available for inhalation asthma therapy, has been reformulated in HFA-134a (Proventil HFA). OBJECTIVE; To compare the efficacy of Proventil HFA to Ventolin, Proventil, and placebo (HFA-134a) MDI in protecting asthmatic patients from exercise-induced bronchoconstriction. METHODS: This was a randomized, single-blind, placebo-controlled, 4-period crossover study of asthmatic patients with documented exercise-induced broncho-constriction. Twenty patients self administered two puffs of either Proventil HFA, Ventolin, Proventil or placebo, from an MDI, 30 minutes prior to performing a standardized exercise challenge at the study site. Spirometry was performed predose and 5, 10, 15, 30, 45, 60, 75, and 90 minutes after completion of the exercise challenge. Heart rate and blood pressure were measured just prior to spirometry and a 12-lead ECG was performed 15 minutes after completion of the exercise challenge for measurement of the QT corrected interval. RESULTS: The primary efficacy variable was the smallest percent change from the predose FEV1 following exercise. The smallest percent change from predose FEV1 for Proventil HFA was 2.0 +/- 9.9 SD, similar to the 2.0 +/- 11.4 SD for Ventolin, and the 3.6 +/- 10.2 SD for Proventil. The smallest percent change from predose FEV1 for each of the active treatments was significantly different from placebo, -23.7 +/- 14.5. Twelve of the patients had a > or = 20% fall in FEV1 post-exercise with placebo pretreatment, but only 1, 1, and 0 had > or = 20% FEV1 falls after treatment with Proventil HFA, Ventolin, and Proventil respectively. Changes in heart rate, blood pressure and QT corrected interval were similar for the three active treatments following exercise. CONCLUSIONS: Proventil HFA provides protection against exercise-induced bronchoconstriction comparable to Ventolin and Proventil and protection superior to placebo. Proventil HFA has a safety profile similar to Ventolin when used to prevent exercise-induced bronchoconstriction.