Use of sequential quadrupling dose regimens to study efficacy of inhaled corticosteroids in asthma

Assessing the Effects of Changing Patterns of Inhaled Corticosteroid Dosing and Adherence with Fluticasone Furoate and Budesonide on Asthma Management

INTRODUCTION

Pharmacological asthma management focuses on the use of inhaled corticosteroid (ICS)-containing therapies, which reduce airway inflammation and provide bronchoprotection, improving symptom control and reducing exacerbation risk. ICS underuse due to poor adherence is common, leading to poor clinical outcomes including increased risk of mortality. This article reviews efficacy versus systemic activity profiles for various adherence patterns and dosing regimens of fluticasone furoate (FF)-containing and budesonide (BUD)-containing asthma therapies in clinical trials and real-world studies.

METHODS

We performed a structured literature review (1 January 2000-3 March 2022) and mathematical modelling analysis of FF-containing and BUD-containing regular daily dosing in patients with mild-to-severe asthma, as-needed BUD/formoterol (FOR) in mild asthma, and BUD/FOR maintenance and reliever therapy (MART) dosing in moderate-to-severe asthma, to assess efficacy (bronchoprotection) and systemic activity (cortisol suppression) profiles of dosing patterns of ICS use in multiple adherence scenarios.

RESULTS

A total of 22 manuscripts were included in full-text review and 18 in the model simulations. Focusing on FF-containing or BUD-containing treatments at comparable adherence rates, regular daily FF or FF/vilanterol (VI) dosing provided more prolonged bronchoprotection and fewer systemic effects than daily BUD, daily BUD/FOR, or BUD/FOR MART dosing, especially in low adherence scenarios. In model simulations and the real-world setting, FF/VI generally provided longer bronchoprotection, lower systemic activity, and greater clinical benefits over BUD/FOR as well as consistently higher adherence.

CONCLUSION

In this literature review and modelling analysis, FF/VI was found to show clinical advantages on asthma control over BUD/FOR. These findings have implications for helping clinicians select the most suitable inhaled therapy for their patients with asthma.

Pharmacology Versus Convenience: A Benefit/Risk Analysis of Regular Maintenance Versus Infrequent or As-Needed Inhaled Corticosteroid Use in Mild Asthma

INTRODUCTION

This study compared the bronchoprotective and benefit/risk profiles of various inhaled corticosteroid (ICS) dosing regimens in mild asthma.

METHODS

A pharmacokinetic/pharmacodynamic model was developed and validated describing the relationship between ICS dose and time-course for airway bronchoprotection, [provocative concentration of adenosine monophosphate (AMP) causing ≥ 20% decline in forced expiratory volume in 1 s (FEV1) (AMP PC20)], for fluticasone furoate (FF), fluticasone propionate (FP) and budesonide (BUD). For regular ICS maintenance therapy (100% and 50% adherence) and infrequent or as-needed use (dosing 3-4 times per week), treatment effectiveness was expressed as percent time during 28 days when bronchoprotection exceeded either the threshold for a treatment-related bronchoprotective effect (AMP PC20 ≥ 0.25 doubling dose) or the threshold for a clinically significant bronchoprotective effect (AMP PC20 ≥ 1.0 doubling dose). This value was divided by the total ICS dose administered expressed in prednisolone equivalents to give a therapeutic index (TI).

RESULTS

The model-predicted time course of ICS-induced bronchoprotection with regular daily maintenance dosing and 100% adherence showed that all ICS at the highest recommended doses for mild asthma exceeded the threshold for clinically significant bronchoprotective effect for all or most of the 28-day dosing period, mean (90% CI); 100% (96.1-100), 99.9% (8.0-100) and 100% (58.2-100) with TI values of 16.9, 6.6 and 5.4 for FF 100 µg OD, FP 200 µg BID and BUD 200 µg BID, respectively. For simulated poor adherence (50%) to regular daily maintenance therapy, corresponding mean (90% CI) values were; 75.7% (39.4-89.1), 52.3% (0.7-69.2) and 51.3% (28.6-58.3) with TI values of 25.7, 6.9 and 5.6. For simulated infrequent/as needed use the corresponding values were; 77.0% (37.6-87.0), 25.5% (0.0-38.0) and 26.2% (14.3-31.5) with TI values of 26.1, 6.7 and 5.7. For all regimen/scenarios, FF had the most sustained efficacy and favourable TI followed by FP and BUD.

CONCLUSIONS

At doses recommended for mild asthma, all ICS regimens provide sustained bronchoprotective efficacy when dosed regularly with high adherence. With poor adherence or use 3-4 times per week (infrequent/as needed), longer-acting ICS molecules will more likely provide sustained protection and a better TI versus shorter duration of action molecules (FF > FP ≥ BUD). These data highlight the benefits of using ICS as regular daily maintenance dosing in mild asthma and the potential risks of under-treatment with ICS (which may occur with ICS/formoterol as-needed approach in mild persistent asthma) associated with reduced levels of bronchoprotection.

Direct and indirect bronchoprovocation tests in dose-response studies of inhaled corticosteroids: Past, present, and future directions

Inhaled corticosteroids (ICS) are a mainstay of treatment in eosinophilic asthma. Many studies have explored the dose-response effect of different formulations of ICS through direct or indirect bronchoprovocation testing. Such studies are important for investigating efficacy and identifying the relative potency between formulations. However, lack of consistency in methods and designs has hindered the comparability of study findings. This review discusses current knowledge of the dose-response, or lack thereof, of different formulations of ICS through direct and indirect bronchoprovocation testing. The strengths and weaknesses of past studies inform recommendations for future methodological considerations in this field, such as utilizing a randomized double-blind crossover design, enrolling participants likely to respond to ICS therapy, and carefully selecting treatment durations and washout periods to assess incremental improvement in airway hyperresponsiveness while reducing the likelihood of a carryover effect.

Therapeutic index of inhaled corticosteroids in asthma: A dose-response comparison on airway hyperresponsiveness and adrenal axis suppression

Aims

To compare the airway potency, systemic activity and therapeutic index of three inhaled corticosteroids that differ in glucocorticoid receptor binding affinity, physicochemical and pharmacokinetic properties.

Methods

This escalating‐dose, placebo‐controlled, cross‐over study randomised adults with asthma to 1 or 2 treatment periods with ≥25 days washout in‐between. Each treatment period comprised five 7‐day dose escalations (μg/d): fluticasone furoate (FF; 25 → 100 → 200 → 400 → 800), fluticasone propionate (FP; 50 → 200 → 500 → 1000 → 2000), budesonide (BUD; 100 → 400 → 800 → 1600 → 3200) or placebo. Airway hyperresponsiveness to adenosine‐5'‐monophosphate (AMP PC₂₀) was assessed on day 8. Plasma cortisol was assessed on day 1 (predose baseline) and from pre‐PM dose on day 6 to pre‐PM dose day 7 (24‐h weighted mean).

Results

Fifty‐four subjects were randomised. FF showed greater airway potency than FP and BUD (AMP PC₂₀ dose at which 50% of the maximum effect is achieved [ED₅₀] values: 48.52, 1081.27 and 1467.36 μg/d, respectively). Systemic activity (cortisol suppression) ED₅₀ values were 899.99, 1986.05 and 1927.42 μg/d, respectively. The therapeutic index (ED₅₀ cortisol suppression/ED₅₀ AMP PC₂₀) was wider for FF (18.55) than FP (1.84) and BUD (1.31). FF 100 μg/d and 200 μg/d were both comparable in terms of airway potency with high doses of FP (≥1000 μg twice daily [BID]) and BUD (≥1500 μg/BID). The systemic activity of FF 100 μg/d and 200 μg/d (cortisol suppression: 7.41% and 14.28%, respectively) was comparable with low doses of FP (100 μg/BID and 250 μg/BID) and BUD (100 μg/BID and 200 μg/BID).

Conclusion

This study provides evidence that FF can provide more protection against airway hyperresponsiveness, with less systemic activity, than FP or BUD. This suggests that all inhaled corticosteroids are not therapeutically similar and may differ in their therapeutic index. (203162; NCT02991859).

Updates on the use of inhaled corticosteroids in asthma

PURPOSE OF REVIEW

The purpose of this review is to compare and contrast the newer inhaled corticosteroid (ICS) ciclesonide with older ICSs in terms of pharmacodynamic and pharmacokinetic properties and how these affect comparative efficacy. In addition, clinical dosing strategies for ICSs including as-needed use will be explored.

RECENT FINDINGS

Ciclesonide has demonstrated similar efficacy to that of fluticasone propionate and mometasone furoate in equipotent doses with a potentially improved therapeutic index. Once-daily administration of ICSs is generally not as effective as twice-daily. Continuous administration of ICSs does not change the natural history of asthma in either children or adults. Long-term administration of medium dose ICSs does not increase the risk of cataracts or osteopenia in children and young adults. Studies of as-needed ICSs in mild persistent asthma in adults and children have demonstrated mixed results, with some showing equal efficacy to continuous therapy and others showing superiority of continuous therapy.

SUMMARY

Ciclesonide provides a newer ICS with favorable pharmacokinetics that may improve the therapeutic index, but assessment of its systemic effects such as growth await further studies. Continuous administration of ICSs in low to medium dose over many years is well tolerated. The use of as-needed ICSs in patients with mild persistent asthma is promising as a potential step-down therapy but awaits further studies.

Inhaled corticosteroid dosing: double for nothing?

Two recent trials from the National Heart, Lung, and Blood Institute's asthma clinical trials networks raise a concern about using double the dose of an inhaled corticosteroid (ICS) as a positive control arm in clinical trials of add-on therapy. The literature evaluating the response to doubling the dose of an ICS is briefly reviewed. The vast majority of studies do not demonstrate a significant positive benefit from doubling the dose of an ICS but do show improvement with 4-fold increases that is equal to or greater than that of add-on long-acting bronchodilators. It is recommended that doubling the dose of an ICS no longer be considered a positive comparator arm in clinical trials, although it might be beneficial in individual patients.

Safety of hookworm infection in individuals with measurable airway responsiveness: a randomized placebo-controlled feasibility study

Background

Epidemiological evidence suggests that hookworm infection protects against asthma. However, for ethical and safety reasons, before testing this hypothesis in a clinical trial in asthma it is necessary to establish whether experimental hookworm infection might exacerbate airway responsiveness during larval lung migration.

Objective

To determine whether hookworm larval migration through the lungs increases airway responsiveness in allergic individuals with measurable airway responsiveness but not clinical asthma, and investigate the general tolerability of infection and effect on allergic symptoms.

Methods

Thirty individuals with allergic rhinoconjunctivitis and measurable airway responsiveness to adenosine monophosphate (AMP) but not clinically diagnosed asthma were randomized, double-blind to cutaneous administration of either 10 hookworm larvae or histamine placebo, and followed for 12 weeks. The primary outcome was the maximum fall from baseline in provocative dose of inhaled AMP required to reduce 1-s forced expiratory volume by 10% (PD₁₀AMP) measured at any time over the 4 weeks after active or placebo infection. Secondary outcomes included peak flow variability in the 4 weeks after infection, rhinoconjunctivitis symptom severity and adverse effect diary scores over the 12-week study period, and change in allergen skin test responses between baseline and 12 weeks.

Results

Mean maximum change in PD₁₀AMP from baseline was slightly but not significantly greater in the hookworm than the placebo group (−1.67 and −1.16 doubling doses; mean difference −0.51, 95% confidence interval −1.80 to 0.78, P=0.42). Symptom scores of potential adverse effects were more commonly reported in the hookworm group, but infection was generally well tolerated. There were no significant differences in peak-flow variability, rhinoconjunctivitis symptoms or skin test responses between groups.

Conclusion

Hookworm infection did not cause clinically significant exacerbation of airway responsiveness and was well tolerated. Suitably powered trials are now indicated to determine the clinical effectiveness of hookworm infection in allergic rhinoconjunctivitis and asthma.

Comparison of inhaled corticosteroids: an update

OBJECTIVE

To review the basis for the estimated comparative daily dosages of inhaled corticosteroids for children and adults that are presented in the National Heart, Lung, and Blood Institute's Expert Panel Report 3; in addition, the pharmacodynamic and pharmacokinetic basis for potential clinical differences among inhaled corticosteroids is discussed.

DATA SOURCES

A complete MEDLINE search was conducted of human studies of asthma pharmacotherapy published between January 1, 2001, and March 15, 2006, followed by a PubMed search up until August 2008, using ciclesonide, inhaled corticosteroids, and pharmacokinetics as key words. Product information on each inhaled corticosteroid was also included.

STUDY SELECTION AND DATA EXTRACTION

Comparative clinical trials of inhaled corticosteroids and systematic reviews for efficacy comparisons were evaluated. Extensive literature reviews, meta-analyses, and selected clinical studies that illustrate or represent specific points of view were selected. Pharmacodynamic and pharmacokinetic data extracted from previously published reviews and specific studies were included.

DATA SYNTHESIS

Pharmacodynamic characteristics (glucocorticoid receptor binding) and lung delivery determine the relative clinical efficacy and pharmacokinetic properties (oral bioavailability, lung retention, systemic clearance) and determine comparative therapeutic index of the inhaled corticosteroids. Secondary pharmacokinetic differences (intracellular fatty acid esterification, high serum protein binding) that have been posited to improve duration of action and/or therapeutic index are unproven, and current comparative clinical trials do not support the hypotheses that they provide an advantage. Ultrafine particle meter-dose inhalers (MDIs) have not demonstrated superior asthma control or improved safety over older MDIs. All of the inhaled corticosteroids demonstrate efficacy with once-daily dosing, and all are more effective when dosed twice daily.

CONCLUSIONS

Current evidence suggests that all of the inhaled corticosteroids have sufficient therapeutic indexes to provide similar efficacy and safety in low to medium doses. Whether or not some of the newer inhaled corticosteroids offer any advantages at higher doses has yet to be determined.

Anti-inflammatory effects of once daily low dose inhaled ciclesonide in mild to moderate asthmatic patients

BACKGROUND

Ciclesonide exhibits clinical efficacy at 160 microg (ex-actuator) once daily but the anti-inflammatory effects at this dose are not known. We wished to know whether 4 weeks therapy with ciclesonide pMDI 160 microg once daily in the morning exhibited significant anti-inflammatory effects.

METHODS

Seventeen patients with mild persistent asthma (FEV(1) 3.35 l) were recruited into a double-blind placebo-controlled randomized crossover study. Measurements were made after ciclesonide and placebo treatment as well as after run-in and washout periods, for adenosine monophosphate (AMP) bronchial challenge (primary variable), exhaled nitric oxide (NO) and induced sputum (in a subgroup).

RESULTS

The mean (SEM) AMP bronchial challenge PC(20) following ciclesonide (140 (63) mg/ml) was significantly (P < 0.001) increased compared with placebo (17 (8) mg/ml), run-in (13 (5) mg/ml) and washout (9 (3) mg/ml) periods. This amounted to an eightfold (CI: 5.3-12.0) for ciclesonide vs placebo. Likewise, there were significant improvements in exhaled NO levels and a significant reduction in induced sputum eosinophil cell counts.

CONCLUSION

We have shown that inhaled ciclesonide given at 160 microg once daily in the morning exhibits significant anti-inflammatory effects that are in keeping with the previously described clinical effects.

Dose-response comparison of budesonide dry powder inhalers using adenosine monophosphate bronchial challenge

BACKGROUND

Bronchial hyperresponsiveness to adenosine monophosphate, an indirect measure of airway inflammation, is a sensitive marker of inhaled corticosteroid efficacy.

OBJECTIVE

To evaluate the relative therapeutic efficacy of budesonide delivered via Clickhaler and Turbuhaler dry powder inhalers in patients with mild-to-moderate persistent asthma.

METHODS

In a double-masked, dose-response crossover study, 27 patients received inhaled budesonide in cumulative sequential doubling dose increments, 2 weeks per dose, of 200, 400, and 800 microg/d. Each treatment block was preceded by 1- to 3-week placebo run-in and washout periods. End points were measured after each placebo (ie, baseline) and treatment period. Adenosine monophosphate bronchial challenge was the primary outcome, and exhaled nitric oxide, serum eosinophilic cationic protein, spirometry, domiciliary peak expiratory flow, symptoms, and rescue medication use were the secondary outcomes.

RESULTS

For the adenosine monophosphate provocation concentration that caused a decrease in forced expiratory volume in 1 second of 20% (PC20), a significant overall dose-response effect (P = .006) was found, and there was no significant difference between the devices (P = .8). The relative microgram dose potency ratio between Clickhaler and Turbuhaler was 1.11 (95% confidence interval [CI], 0.50-2.46). After administration of the highest dose of budesonide, the mean doubling dilution shift in adenosine monophosphate PC20 from placebo baseline was 3.46 (95% CI, 2.66-4.27) with the Clickhaler vs 3.41 (95% CI, 2.47-4.35) with the Turbuhaler. A significant overall dose-response effect was demonstrated for exhaled nitric oxide (P = .03) but not for any of the other secondary outcome measures. There were no significant differences between the devices for any of the outcome measures.

CONCLUSION

Inhaled budesonide exhibited overall dose-response effects on adenosine monophosphate PC20 delivered via Turbuhaler and Clickhaler, with no significant difference between the devices.

Time course of action of two inhaled corticosteroids, fluticasone propionate and budesonide

BACKGROUND

It is important to be able to compare the efficacy and systemic effects of inhaled corticosteroids but their slow onset of action makes it difficult to measure the maximum response to a given dose. Submaximal responses could be compared if the time course of action of the inhaled corticosteroids being compared was similar. We have compared the time course of action of fluticasone and budesonide, measuring response as change in the provocative dose of adenosine monophosphate causing a 20% fall in forced expiratory volume in 1 second (PD20AMP).

METHODS

Eighteen subjects with mild asthma, aged 18-65, took part in a three way randomised crossover study. Subjects took fluticasone (1500 microg/day), budesonide (1600 microg/day), and placebo each for 4 weeks with a washout period of at least 2 weeks between treatments; PD20AMP and forced expiratory volume in 1 second (FEV1) were measured during and after treatment. The time taken to achieve 50% of the maximum response (T50%) was compared as a measure of onset of action.

RESULTS

There was a progressive increase in PD20AMP during the 4 weeks of treatment with both fluticasone and budesonide but not placebo; the increase after 1 and 4 weeks was 2.28 and 4.50 doubling doses (DD) for fluticasone and 2.49 and 3.65 DD for budesonide. T50% was 9.3 days for fluticasone and 7.5 days for budesonide with a median difference between fluticasone and budesonide of 0.1 days (95% CI -1.4 to 2.65). There was a wide range of response to both inhaled corticosteroids but good correlation between the response to fluticasone and budesonide within subjects. FEV1 and morning peak expiratory flow rate (PEFR) increased during the first week of both active treatments and were stable thereafter. There was a small progressive improvement in nocturnal symptoms with both active treatments.

CONCLUSION

PD20AMP was a more sensitive marker of response to inhaled corticosteroid therapy than FEV1 and PEFR. The time course of action of fluticasone and budesonide on PD20AMP is similar, suggesting that comparative studies of their efficacy using 1 or 2 week treatment periods are valid. When a new inhaled corticosteroid becomes available, a pilot study comparing its time course of action with that of an established corticosteroid should allow comparative studies to be performed more efficiently.