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Karjalainen J, Vartiainen V, Tikkakoski A, Malmberg LP, Vuotari L, Lähelmä S, Sairanen U, Vahteristo M, Lehtimäki L. Salbutamol Easyhaler provides non-inferior relief of methacholine induced bronchoconstriction in comparison to Ventoline Evohaler with spacer: A randomized trial. Respir Med 2024; 230:107693. [PMID: 38851404 DOI: 10.1016/j.rmed.2024.107693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 05/17/2024] [Accepted: 06/03/2024] [Indexed: 06/10/2024]
Abstract
BACKGROUND Salbutamol is a cornerstone for relieving acute asthma symptoms, typically administered through a pressurized metered-dose inhaler (pMDI). Dry powder inhalers (DPIs) offer an alternative, but concerns exist whether DPIs provide an effective relief during an obstructive event. OBJECTIVE We aimed to show non-inferiority of Salbutamol Easyhaler DPI compared to pMDI with spacer in treating methacholine-induced bronchoconstriction. Applicability of Budesonide-formoterol Easyhaler DPI as a reliever was also assessed. METHODS This was a randomized, parallel-group trial in subjects sent to methacholine challenge (MC) test for asthma diagnostics. Participants with at least 20 % decrease in forced expiratory volume in 1 s (FEV1) were randomized to receive Salbutamol Easyhaler (2 × 200 μg), Ventoline Evohaler with spacer (4 × 100 μg) or Budesonide-formoterol Easyhaler (2 × 160/4.5 μg) as a reliever. The treatment was repeated if FEV1 did not recover to at least -10 % of baseline. RESULTS 180 participants (69 % females, mean age 46 yrs [range 18-80], FEV1%pred 89.5 [62-142] %) completed the trial. Salbutamol Easyhaler was non-inferior to pMDI with spacer in acute relief of bronchoconstriction showing a -0.083 (95 % LCL -0.146) L FEV1 difference after the first dose and -0.032 (-0.071) L after the last dose. The differences in FEV1 between Budesonide-formoterol Easyhaler and Salbutamol pMDI with spacer were -0.163 (-0.225) L after the first and -0.092 (-0.131) L after the last dose. CONCLUSION The study confirms non-inferiority of Salbutamol Easyhaler to Ventoline Evohaler with spacer in relieving acute bronchoconstriction, making Easyhaler a sustainable and safe reliever for MC test and supports its use during asthma attacks.
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Affiliation(s)
- Jussi Karjalainen
- Allergy Centre, Tampere University Hospital, Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Ville Vartiainen
- Heart and Lung Center, Helsinki University Hospital, Finland and Faculty of Medicine, University of Helsinki, Finland
| | - Antti Tikkakoski
- Clinical Physiology and Nuclear Medicine, Tampere University Hospital, Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - L Pekka Malmberg
- Skin and Allergy Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Liisa Vuotari
- Clinical Physiology and Nuclear Medicine, Tampere University Hospital, Faculty of Medicine and Life Sciences, University of Tampere, Finland
| | | | | | | | - Lauri Lehtimäki
- Allergy Centre, Tampere University Hospital, Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
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Allan R, Haughie S, Ahrens R, Singh S, Ward J. A Dose-Response Study Examining the Use of Methacholine Challenge to Demonstrate Local Therapeutic Equivalence of the Salmeterol Component of Generic Inhaled Fluticasone Propionate/Salmeterol Combination Products. J Aerosol Med Pulm Drug Deliv 2019; 32:352-363. [PMID: 31259673 DOI: 10.1089/jamp.2018.1519] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Background: Asthma is widely treated using inhaled corticosteroid/long-acting beta agonist (LABA) combinations, for example, fluticasone propionate/salmeterol (FPS) dry powder inhaler, marketed as Advair® Diskus®. Some regulators require generics to demonstrate local (lung) therapeutic equivalence (LTE) for each component of the FPS reference, ideally with a dose-response within the approved FPS dose range. We sought to develop a methacholine challenge (MeCh) LTE methodology for assessing the LABA (salmeterol) component of FPS. Methods: Forty-six patients with asthma received single doses of albuterol (active control; 90 or 180 μg), FPS (100/50 or 200/100 μg), and placebo on 5 separate study days. Spirometry and MeCh were performed 1, 6, and 10 hours after study drug inhalation. Primary endpoint was provocative concentration of methacholine producing a 20% fall in forced expiratory volume in 1 second (PC20). Study entry required screening PC20 ≤8 mg/mL, with a greater than fourfold increase (and PC20 ≤128 mg/mL) after 180 μg albuterol. Results: Both albuterol (90 and 180 μg) and FPS (100/50 and 200/100 μg) significantly increased PC20 compared with placebo (sustained 6 and 10 hours postdose with FPS but not albuterol). The dose-response slopes (95% confidence interval) estimated 1 hour after treatment were 0.374 (-0.068 to 0.815) and 0.310 (-0.135 to 0.754) between low and high doses of albuterol and FPS, respectively, both nonsignificant. Slopes were shallower than those available in the literature for albuterol and formoterol, but similar to those for salmeterol. Conclusions: These data confirm that the bronchoprotective effect of FPS lasts longer than that of albuterol. The shallow dose-response slope we observed for albuterol is contrary to previous reports, probably due to the measurement of PC20 beginning at 1 hour postdose. The results suggest that use of MeCh to assess LTE for salmeterol formulations may be more difficult to accomplish than it is for albuterol and formoterol products.
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Affiliation(s)
| | | | - Richard Ahrens
- Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Sachinkumar Singh
- Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Jon Ward
- Mylan Pharma UK Limited, Sandwich, United Kingdom
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Zeng Y, Singh S, Wang K, Ahrens RC. Effect of Study Design on Sample Size in Studies Intended to Evaluate Bioequivalence of Inhaled Short-Acting β-Agonist Formulations. J Clin Pharmacol 2017; 58:457-465. [PMID: 29281130 PMCID: PMC5901014 DOI: 10.1002/jcph.1045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 10/23/2017] [Indexed: 11/15/2022]
Abstract
Pharmacodynamic studies that use methacholine challenge to assess bioequivalence of generic and innovator albuterol formulations are generally designed per published Food and Drug Administration guidance, with 3 reference doses and 1 test dose (3‐by‐1 design). These studies are challenging and expensive to conduct, typically requiring large sample sizes. We proposed 14 modified study designs as alternatives to the Food and Drug Administration–recommended 3‐by‐1 design, hypothesizing that adding reference and/or test doses would reduce sample size and cost. We used Monte Carlo simulation to estimate sample size. Simulation inputs were selected based on published studies and our own experience with this type of trial. We also estimated effects of these modified study designs on study cost. Most of these altered designs reduced sample size and cost relative to the 3‐by‐1 design, some decreasing cost by more than 40%. The most effective single study dose to add was 180 μg of test formulation, which resulted in an estimated 30% relative cost reduction. Adding a single test dose of 90 μg was less effective, producing only a 13% cost reduction. Adding a lone reference dose of either 180, 270, or 360 μg yielded little benefit (less than 10% cost reduction), whereas adding 720 μg resulted in a 19% cost reduction. Of the 14 study design modifications we evaluated, the most effective was addition of both a 90‐μg test dose and a 720‐μg reference dose (42% cost reduction). Combining a 180‐μg test dose and a 720‐μg reference dose produced an estimated 36% cost reduction.
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Affiliation(s)
- Yaohui Zeng
- Department of Biostatistics, College of Public Health, University of Iowa, Iowa City, IA, USA
| | - Sachinkumar Singh
- Stead Family Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Kai Wang
- Department of Biostatistics, College of Public Health, University of Iowa, Iowa City, IA, USA
| | - Richard C Ahrens
- Stead Family Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
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Bjermer L, Gauvreau GM, Postma DS, O'Byrne PM, van den Berge M, Boulet LP, Beckman O, Persson T, Román J, Carlholm M, Schützer KM, Eckerwall G. Methacholine challenge tests to demonstrate therapeutic equivalence of terbutaline sulfate via different Turbuhaler ® devices in patients with mild to moderate asthma: Appraisal of a four-way crossover design. Pulm Pharmacol Ther 2017; 44:1-6. [PMID: 28232118 DOI: 10.1016/j.pupt.2017.02.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 02/16/2017] [Accepted: 02/16/2017] [Indexed: 11/16/2022]
Abstract
BACKGROUND/OBJECTIVE To demonstrate therapeutic equivalence of terbutaline via two different Turbuhaler® devices by evaluating its protective effect against methacholine-induced bronchoconstriction in stable asthma. METHODS In this double-blind, double-dummy, multicentre, single-dose, 4-way crossover study, patients with stable mild-to-moderate asthma (FEV1 ≥80% predicted) were randomised to 0.5 or 1.5 mg terbutaline via either Turbuhaler® M2 or Turbuhaler® M3 followed by a methacholine challenge test. The primary outcome variable was the concentration of methacholine causing a 20% drop in FEV1 (PC20). Patients had a PC20 methacholine <8 mg/mL that was reproducible after 2 weeks, and a stable baseline FEV1 at all visits (90-110% of enrolment value). RESULTS 60 patients (mean age 31.1 years [range:18-64]; mean FEV1 92.1% predicted normal [78.4-120.6%]) were randomised to treatment; all completed the study. There was a clear dose-response for both devices. The within-device ratios (1.5 mg:0.5 mg) were 1.79 and 1.87 for Turbuhaler® M3 and M2, respectively (both p < 0.001). The between-device ratios (M3:M2) were 0.92 (95% CI: 0.75-1.13) for 0.5 mg and 0.88 (95% CI 0.72-1.08) for 1.5 mg. Both confidence intervals lie inside the interval 0.67-1.50, which was the pre-specified condition for equivalent effect. CONCLUSIONS Bronchoprotection using a standardised methacholine challenge model proved to be an effective design to elucidate therapeutic equivalence between devices in patients with mild-to-moderate asthma. The findings indicate that patients may switch from one type of Turbuhaler® to the other without adjustment of therapy. Moreover, they show the robustness and utility of this study design and its suitability for investigating therapeutic equivalence. EUDRACT NUMBER 2014-001457-16. CLINICALTRIALS. GOV IDENTIFIER NCT02322788.
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Affiliation(s)
- Leif Bjermer
- Department of Respiratory Medicine & Allergology, Skåne University Hospital, Lund, Sweden.
| | - Gail M Gauvreau
- Michael G DeGroote School of Medicine, McMaster University, Hamilton, Canada
| | - Dirkje S Postma
- University of Groningen, Department of Pulmonary Diseases, University Medical Center Groningen, GRIAC Research Institute, Groningen, The Netherlands
| | - Paul M O'Byrne
- Michael G DeGroote School of Medicine, McMaster University, Hamilton, Canada
| | - Maarten van den Berge
- University of Groningen, Department of Pulmonary Diseases, University Medical Center Groningen, GRIAC Research Institute, Groningen, The Netherlands
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Mondal P, Baumstein S, Prabhakaran S, Abu-Hasan M, Zeng Y, Singh S, Wang K, Ahrens RC, Hendeles L. Bioassay of salmeterol in children using methacholine challenge with impulse oscillometry. Pediatr Pulmonol 2016; 51:570-5. [PMID: 26575323 DOI: 10.1002/ppul.23345] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 10/08/2015] [Accepted: 10/27/2015] [Indexed: 11/10/2022]
Abstract
BACKGROUND Bronchoprovocation with methacholine (MC) is the most sensitive method of determining bioequivalence of inhaled bronchodilators. FEV1 is used to determine the endpoint, but many children cannot perform spirometry reproducibly. The purpose of this study was to determine whether MC, using impulse oscillometry (IOS) as the endpoint, can differentiate between two doses of salmeterol (SM). METHODS This was a single-blind, randomized study of 10 subjects with mild stable asthma, ages 4-11 years. None were taking a long-acting β-agonist but most were on low-dose inhaled corticosteroid. On one study day, MC was performed 1 hr after one inhalation from each of two separate Advair 100/50 Diskus (100 μg salmeterol treatment). On a second day, MC was performed after one inhalation from Advair Diskus and one inhalation from Flovent Diskus 100 (50 μg salmeterol treatment). The provocative concentration of methacholine causing a 40% increase in total airway resistance (PC40 R5 ) was calculated. RESULTS The reduction in R5 (bronchodilator effect) was 15.5% and 18.4% for 50 and 100 μg, respectively (NS). After MC (bronchoprotective effect), the geometric mean (95%CI) PC40 R5 (mg/ml) was 2.4 (1.3-4.4) during screening, 22.9 (8.5-61.6) after 50 μg SM and 47.0 (25.2-87.8) after 100 μg SM (P = 0.051 for 50 vs. 100 using a linear mixed effects model). No adverse effects were observed. CONCLUSIONS MC with IOS endpoint will be a useful method for determining bioequivalence of a generic inhaler in children. Seventy-two subjects will be required to achieve 80% power to assess bioequivalence of SM. Pediatr Pulmonol. 2016;51:570-575. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Pritish Mondal
- Department of Pediatrics, College of Medicine, Penn State University, State College, Pennsylvania
| | - Sandra Baumstein
- Department of Pharmacotherapy and Translational Research, College of Pharmacy, University of Florida, Gainesville, Florida
| | - Sreekala Prabhakaran
- Department of Pediatrics, College of Medicine, University of Florida, Gainesville, Florida
| | - Mutasim Abu-Hasan
- Department of Pediatrics, College of Medicine, University of Florida, Gainesville, Florida
| | - Yaohui Zeng
- Department of Biostatistics, College of Public Health, University of Iowa, Iowa City, Iowa
| | - Sachinkumar Singh
- Stead Family Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Kai Wang
- Department of Biostatistics, College of Public Health, University of Iowa, Iowa City, Iowa
| | - Richard C Ahrens
- Stead Family Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Leslie Hendeles
- Department of Pharmacotherapy and Translational Research, College of Pharmacy and Department of Pediatrics, University of Florida, Gainesville, FL
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Hendeles L, Daley-Yates PT, Hermann R, De Backer J, Dissanayake S, Horhota ST. Pharmacodynamic Studies to Demonstrate Bioequivalence of Oral Inhalation Products. AAPS JOURNAL 2015; 17:758-68. [PMID: 25716149 DOI: 10.1208/s12248-015-9735-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 02/03/2015] [Indexed: 11/30/2022]
Abstract
In the session on "Pharmacodynamic studies to demonstrate efficacy and safety", presentations were made on methods of evaluating airway deposition of inhaled corticosteroids and bronchodilators, and systemic exposure indirectly using pharmacodynamic study designs. For inhaled corticosteroids, limitations of measuring exhaled nitric oxide and airway responsiveness to adenosine for anti-inflammatory effects were identified, whilst measurement of 18-h area under the cortisol concentration-time curve was recommended for determining equivalent systemic exposure. For bronchodilators, methacholine challenge was recommended as the most sensitive method of determining the relative amount of β-agonist or anti-muscarinic agent delivered to the airways. Whilst some agencies, such as the Food and Drug Administration (FDA), do not require measuring systemic effects when pharmacokinetic measurements are feasible, the European Medicines Agency requires measurement of heart rate and serum potassium, and some require serial electrocardiograms when bioequivalence is not established by pharmacokinetic (PK) studies. The Panel Discussion focused on whether PK would be the most sensitive marker of bioequivalence. Furthermore, there was much discussion about the FDA draft guidance for generic fluticasone propionate/salmeterol. The opinion was expressed that the study design is not capable of detecting a non-equivalent product and would require an unfeasibly large sample size.
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Affiliation(s)
- Leslie Hendeles
- Pharmacotherapy and Translational Research and Pediatrics (Pulmonary), University of Florida, PO Box 100486, Gainesville, Florida, 32610-0486, USA,
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Prabhakaran S, Shuster J, Chesrown S, Hendeles L. Response to albuterol MDI delivered through an anti-static chamber during nocturnal bronchospasm. Respir Care 2012; 57:1291-6. [PMID: 22348270 DOI: 10.4187/respcare.01572] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Decreasing electrostatic charge on valved holding chambers increases the amount of drug delivered. However, there are no data demonstrating that this increases bronchodilatation. OBJECTIVE To investigate the influence of reducing electrostatic charge on the bronchodilator response to albuterol inhaler during nocturnal bronchospasm. METHODS This randomized double-blind, double-dummy crossover study included subjects, 18-40 years old, with nocturnal bronchospasm (20% overnight decrease in peak flow on 3 of 7 nights during run-in), FEV(1) 60-80% predicted during the day, and ≥ 12% increase after albuterol. Subjects slept in the clinical research center up to 3 nights for each treatment. FEV(1) and heart rate were measured upon awakening spontaneously or at 4:00 am, and 15 min after each dose of 1, 2, and 4 cumulative puffs of albuterol via metered-dose inhaler. The drug was administered through an anti-static valved holding chamber (AeroChamber Plus Z-Stat) or a conventional valved holding chamber containing a static charge (AeroChamber Plus). RESULTS Of 88 consented subjects, 11 were randomized and 7 completed the study. Most exclusions were due to lack of objective evidence of nocturnal bronchospasm. Upon awakening, FEV(1) was 44 ± 9% of predicted before the anti-static chamber and 48 ± 7% of predicted before the static chamber. The mean ± SD percent increase in FEV(1) after 1, 2, and 4 cumulative puffs using the anti-static versus the static chamber, respectively, were 52 ± 26% versus 30 ± 19%, 73 ± 28% versus 48 ± 26%, and 90 ± 34% versus 64 ± 35%. The point estimates for the differences (and 95% CIs) between the devices (anti-static vs static) were 21% (4-38%) (P = .03), 23% (6-41%) (P = .02), and 25% (7-42%) (P = .01) for 1, 2, and 4 cumulative puffs, respectively. There was no significant difference in heart rate between treatments. CONCLUSIONS Delivery of albuterol through an anti-static chamber provides a clinically relevant improvement in bronchodilator response during acute, reversible bronchospasm such as nocturnal bronchospasm.
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Affiliation(s)
- Sreekala Prabhakaran
- Pediatric Pulmonary Division, Department of Pediatrics, University of Florida, Gainesville, Florida, USA
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Abstract
Dry powder inhalers are a diverse family of devices that have emerged as a rapidly growing segment of the respiratory therapeutics area. The forces that these devices must impart into dry powder formulations for effective dispersion performance and reproducibility of delivery are relatively large, and multiple mechanisms have been developed in attempts to improve the efficiency of these systems. In this review, we address the reasons for the proliferation of dry powder inhalers, beginning with an abbreviated introduction on the basic inter-particulate forces that need to be disrupted to achieve successful powder dispersion and effective lung delivery. From this background, we survey the diversity of inhaler designs, starting from marketed devices, before introducing some of the novel device designs under development, both patient driven (passive) and device driven (active), as we attempt to link the themes of the device design features to the present understanding of the dynamics governing powder dispersion. Finally, we conclude by providing some assessment on the future of the wide range of device designs and mechanisms that have evolved by considering technical, regulatory and market forces.
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Prabhakaran S, Shuster J, Ahrens R, Hendeles L. Methacholine challenge as a clinical bioassay of pulmonary delivery of a long-acting β₂-adrenergic agonist. Pharmacotherapy 2011; 31:449-57. [PMID: 21923426 PMCID: PMC3845881 DOI: 10.1592/phco.31.5.449] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
STUDY OBJECTIVE To determine whether the methacholine challenge method used for albuterol can be applied to assess long-acting β2-adrenergic agonist (LABA) bioequivalence, which would require a sufficiently steep dose-response curve. DESIGN Prospective, unblinded, randomized, 2-way crossover study. SETTING University medical center clinical research laboratory. PATIENTS Ten adults, aged 21-58 years, with mild asthma (forced expiratory volume in 1 sec [FEV(1)] ≥ 70% predicted) and a baseline provocational concentration of methacholine required to decrease FEV(1) by 20% (PC(20)) of 4 mg/ml or less completed the study. INTERVENTION Patients were randomized to receive a single dose of either 12 or 24 μg of formoterol delivered by a dry powder inhaler; 3-7 days later, at the same time of day, they received the other dose. MEASUREMENTS AND MAIN RESULTS The FEV(1) was measured before and 1 hour after dosing, followed by performance of a methacholine challenge. Statistical analysis was performed by the 2-sample regression method for crossover studies. The dose-response curve for bronchodilatation was flat; the mean ± SD increase in FEV(1) after formoterol 12 and 24 μg was 14 ± 5% and 14 ± 8%, respectively (p>0.05). In contrast, the geometric mean PC20 (95% confidence interval) was 7 mg/ml (2-22 mg/ml) after the 12-μg dose and 16 mg/ml (5-45 mg/ml) after the 24-μg dose (p<0.001). CONCLUSION Bioassay by methacholine challenge will be useful for bioequivalence studies of LABAs. A sample of at least 28 patients will be required for formoterol when methacholine challenge is performed in an optimal manner. The sample size may differ for other LABAs.
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Affiliation(s)
- Sreekala Prabhakaran
- Pediatric Pulmonary Division, University of Florida, Gainesville, Florida 32610-0486, USA
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Abstract
Albuterol (salbutamol outside the USA) is used to acutely relieve symptoms related to airway obstruction and prevent exercise-induced bronchospasm. Albuterol is most commonly administered by metered-dose inhaler (MDI). MDIs had used chlorofluorocarbon (CFC) propellants, but CFCs accumulate in the stratosphere and contribute to ozone catabolism. Loss of the 'ozone layer', which filters UVB rays, has public health concerns. Albuterol has been reformulated in MDIs using hydrofluoroalkane (HFA) propellants, which do not affect the ozone layer. Albuterol HFA MDIs deliver the same amount of drug per puff with similar particle size distributions as albuterol CFC MDIs, resulting in comparable bronchodilator efficacy of the two products. The highly favorable safety profile of albuterol has not been altered with reformulation. The propellant HFA-134a appears to be devoid of safety concerns.
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Affiliation(s)
- Gene L Colice
- The George Washington University School of Medicine, and Pulmonary, Critical Care and Respiratory Services, Washington Hospital Center, 110 Irving Street, NW Washington, DC 20010, USA.
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Adams WP, Ahrens RC, Chen ML, Christopher D, Chowdhury BA, Conner DP, Dalby R, Fitzgerald K, Hendeles L, Hickey AJ, Hochhaus G, Laube BL, Lucas P, Lee SL, Lyapustina S, Li B, O'Connor D, Parikh N, Parkins DA, Peri P, Pitcairn GR, Riebe M, Roy P, Shah T, Singh GJP, Sharp SS, Suman JD, Weda M, Woodcock J, Yu L. Demonstrating Bioequivalence of Locally Acting Orally Inhaled Drug Products (OIPs): Workshop Summary Report. J Aerosol Med Pulm Drug Deliv 2010; 23:1-29. [DOI: 10.1089/jamp.2009.0803] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Wallace P. Adams
- Food and Drug Administration, Center for Drug Evaluation and Research, Office of Pharmaceutical Science, Office of Generic Drugs, Rockville, Maryland
| | - Richard C. Ahrens
- University of Iowa Hospitals and Clinics, Department of Pediatrics, Iowa City, Iowa
| | - Mei-Ling Chen
- Food and Drug Administration, Center for Drug Evaluation and Research, Silver Spring, Maryland
| | | | - Badrul A. Chowdhury
- Food and Drug Administration, Center for Drug Evaluation and Research, Silver Spring, Maryland
| | - Dale P. Conner
- Food and Drug Administration, Center for Drug Evaluation and Research, Office of Pharmaceutical Science, Office of Generic Drugs, Rockville, Maryland
| | | | | | | | | | - Günther Hochhaus
- Department of Pharmaceutics, College of Pharmacy, University of Florida, Gainesville, Florida
| | - Beth L. Laube
- Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Paul Lucas
- Pfizer Global Research and Development, Sandwich, Kent, CT13 9NJ, United Kingdom
| | - Sau L. Lee
- Food and Drug Administration, Center for Drug Evaluation and Research, Office of Pharmaceutical Science, Office of Generic Drugs, Rockville, Maryland
| | | | - Bing Li
- Food and Drug Administration, Center for Drug Evaluation and Research, Office of Pharmaceutical Science, Office of Generic Drugs, Rockville, Maryland
| | - Dennis O'Connor
- Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, Connecticut
| | | | | | - Prasad Peri
- Food and Drug Administration, Center for Drug Evaluation and Research, Silver Spring, Maryland
| | - Gary R. Pitcairn
- Pfizer Limited, Ramsgate Road, Sandwich, Kent, CT13 9NJ, United Kingdom
| | | | - Partha Roy
- Food and Drug Administration, Center for Drug Evaluation and Research, Silver Spring, Maryland
| | | | | | - Sandra Suarez Sharp
- Food and Drug Administration, Center for Drug Evaluation and Research, Silver Spring, Maryland
| | | | - Marjolein Weda
- National Institute for Public Health and the Environment (RIVM) Centre for Quality of Chemical-Pharmaceutical Products, Bilthoven, The Netherlands
| | - Janet Woodcock
- Food and Drug Administration, Center for Drug Evaluation and Research, Silver Spring, Maryland
| | - Lawrence Yu
- Food and Drug Administration, Center for Drug Evaluation and Research, Office of Pharmaceutical Science, Office of Generic Drugs, Rockville, Maryland
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Tripp K, McVicar WK, Nair P, Corren J, Pleskow WW, Goodwin E, Baumgartner RA, Hanrahan JP. A cumulative dose study of levalbuterol and racemic albuterol administered by hydrofluoroalkane-134a metered-dose inhaler in asthmatic subjects. J Allergy Clin Immunol 2008; 122:544-9. [PMID: 18692886 DOI: 10.1016/j.jaci.2008.06.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Revised: 05/16/2008] [Accepted: 06/09/2008] [Indexed: 11/15/2022]
Abstract
BACKGROUND The short-acting beta(2)-agonists levalbuterol and racemic albuterol are available for administration through a hydrofluoroalkane-134a (HFA) metered-dose inhaler (MDI). OBJECTIVE This study compared the short-term safety and efficacy of cumulative doses of levalbuterol HFA MDI and racemic albuterol HFA MDI in asthmatic subjects. METHODS This was a randomized, modified-blind, active-controlled, multicenter, 2-way crossover study. Subjects (n = 49) were randomized to 16 cumulative doses (1x, 2x, 4x, 8x, and 16x) of levalbuterol (45 microg per dose) or racemic albuterol (90 microg per dose) administered over a 2-hour period. After a 7-day washout period, subjects were crossed over to the other treatment. After each dose, safety outcomes and pulmonary function were assessed. RESULTS Heart rate and (R)-albuterol exposure increased for both racemic albuterol HFA and levalbuterol HFA. For cumulative doses of 8x or greater, racemic albuterol HFA treatment had greater increases in mean heart rate than levalbuterol HFA (least-squares mean [+/- SD] difference at the 8x dose was 2.8 beats/min [95% CI, 0.3-5.3] and at the 16x dose was 3.5 beats/min [95% CI, 0.6-6.4]). (R)-albuterol plasma levels ranged from 10% to 18% higher after racemic albuterol HFA MDI dosing versus after levalbuterol HFA MDI. FEV(1) improvements were similar for both treatments. The relative potencies of the 2 therapies, based on FEV(1), were similar (ratio, 1.1 [90% CI, 0.9-1.2]; Finney method). CONCLUSION In this study single-day cumulative dosing of asthmatic subjects with levalbuterol HFA MDI or racemic albuterol HFA MDI resulted in similar improvements in FEV(1) and tolerability. Plasma (R)-albuterol levels and mean heart rate were less with levalbuterol HFA MDI.
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Lavorini F, Geri P, Camiciottoli G, Pistolesi M, Fontana GA. Agreement between two methods for assessing bioequivalence of inhaled salbutamol. Pulm Pharmacol Ther 2007; 21:380-4. [PMID: 17997115 DOI: 10.1016/j.pupt.2007.10.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2007] [Revised: 09/14/2007] [Accepted: 10/06/2007] [Indexed: 11/19/2022]
Abstract
For inhaled medications, bioequivalence testing is becoming increasingly important owing to the availability of many inhalation devices. We evaluated agreement between the Finney bioassay and the Emax model in the assessment of bioequivalence of salbutamol administered via a metered-dose inhaler with a spacer (pMDI+ Volumatic) or via a dry-powder inhaler (Diskus) in asthmatic patients with methacholine-induced bronchoconstriction. Eighteen patients inhaled methacholine until FEV 1 decreased by approximately 35% of control. Following inhalation of placebo, 200 and 400 mcg salbutamol through the pMDI+ Volumatic or the Diskus, changes in FEV 1 were repeatedly measured over a 60-min observation period. Bioequivalence of salbutamol administered via the two inhalation devices was assessed by calculating the relative potency of each device by using the Finney 2-by-2 parallel regression analysis and the non-linear, Emax model. Agreement between these methods in calculating relative potency was evaluated by using the Bland-Altman method. After salbutamol FEV 1 values were similar irrespective of the device employed, and greater (P<0.01) than those after placebo. However, assessment of relative potencies obtained with both the Finney (1.97, 90% CI 1.62-2.32) and the Emax (2.25, 90% CI 1.90-2.60) methods revealed that twice the salbutamol dose was needed to reverse methacholine-induced bronchoconstriction when the drug was inhaled via the Diskus than via the pMDI+ Volumatic. The mean difference in relative potency (-0.28, 90% CI -0.001 to -0.56) calculated with both methods did not significantly differ from zero, and none of the individual differences exceeded the limits of agreement. The Finney and the Emax methods provide comparable results in the evaluation of bioequivalence of different salbutamol formulations. The pMDI+ Volumatic is twice as efficient as the Diskus in lung delivery of salbutamol in asthma patients.
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Affiliation(s)
- Federico Lavorini
- Dipartimento di Area Critica Medico Chirurgica, Unità Funzionale di Medicina Respiratoria, Università degli Studi di Firenze, Viale G B Morgagni 85-50134, Firenze, Italy.
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14
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Hendeles L, Colice GL, Meyer RJ. Withdrawal of albuterol inhalers containing chlorofluorocarbon propellants. N Engl J Med 2007; 356:1344-51. [PMID: 17392304 DOI: 10.1056/nejmra050380] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Leslie Hendeles
- College of Pharmacy and the Pediatric Pulmonary Division, University of Florida, Gainesville, FL 32610-0486, USA.
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Lavorini F, Geri P, Mariani L, Marmai C, Maluccio NM, Pistolesi M, Fontana GA. Speed of onset of bronchodilator response to salbutamol inhaled via different devices in asthmatics: a bioassay based on functional antagonism. Br J Clin Pharmacol 2006; 62:403-11. [PMID: 16995861 PMCID: PMC1885153 DOI: 10.1111/j.1365-2125.2006.02641.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2005] [Accepted: 01/24/2006] [Indexed: 11/28/2022] Open
Abstract
AIMS To evaluate the speed of onset of bronchodilation following salbutamol administered via a metered-dose inhaler with a spacer (pMDI + Volumatic) and a dry-powder inhaler (Diskus), as well as the relative potencies of these devices in asthmatic patients with methacholine-induced bronchoconstriction. METHODS Eighteen patients inhaled methacholine (MCh) until FEV(1) decreased by 35% of control. Following administration of placebo, 200 microg salbutamol or 400 microg salbutamol through the pMDI + Volumatic or the Diskus, we calculated the time elapsed from drug administration and the appearance of a 90% increase in post-MCh forced vital capacity (FVC), FEV(1) and volume-adjusted mid-expiratory flow (recovery times). The salbutamol doses to be delivered by the two inhalation devices to achieve similar recovery times and the relative potencies of the devices were calculated by using the 2-by-2 Finney parallel regression method. RESULTS For all functional variables, recovery times were significantly (P < 0.01) shorter in pMDI + Volumatic than Diskus trials. The salbutamol doses to be delivered by the Diskus to achieve recovery times for FVC, FEV(1) and volume-adjusted mid-expiratory flow similar to those obtained with 200 microg salbutamol administered via the pMDI + Volumatic were 558 (95% CI 537, 579) microg, 395 (95% CI 388, 404) microg and 404 (95% CI 393, 415) microg, respectively, and corresponded to relative potencies of 2.79 (95% CI 2.68, 2.90), 1.98 (95% CI 1.94, 2.02), and 2.02 (95% CI 1.96, 2.07). CONCLUSIONS Administration of salbutamol via the pMDI + Volumatic provides faster reversal of induced bronchoconstriction than via the Diskus. The salbutamol dose targeting the lungs with the pMDI + Volumatic is approximately twice that with the Diskus.
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Affiliation(s)
- Federico Lavorini
- Dipartimento di Area Critica Medico Chirurgica, Unità Funzionale di Medicina Respiratoria, Università degli Studi di Firenze, Italia.
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Lipworth BJ, Sims EJ, Das SK, Morice AH, O'Connor BJ. Bronchoprotection with formoterol via dry powder and metered-dose inhalers in patients with asthma. Ann Allergy Asthma Immunol 2005; 95:283-90. [PMID: 16200820 DOI: 10.1016/s1081-1206(10)61226-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
BACKGROUND Determination of device comparability for new inhaled medications is essential. OBJECTIVE To evaluate the methacholine bronchoprotection afforded by formoterol, 12 microg, delivered via Clickhaler and Aerolizer dry powder inhalers and a pressurized metered-dose inhaler (pMDI) in mild-to-moderate asthmatic patients. METHODS Two separate randomized, double-blind, double-dummy, crossover studies were performed. Peak bronchoprotection (30 minutes) was measured after administration of a single dose in a placebo-controlled study (n = 16). First-dose (8 hours) and trough (12 hours) protection were evaluated after 2 weeks (n = 28). Doubling dilution differences (DDD) in the methacholine provocation concentration that caused a decrease in forced expiratory volume in 1 second of 20% from baseline were compared, with equivalence defined if the 95% confidence interval was within the predefined equivalence limits of +/- 1.5 DDD (peak) and +/- 1.0 DDD (trough). RESULTS For peak single-dose effects, DDD (95% confidence interval) data showed significant protection vs placebo for all devices but no significant differences among active inhalers. For trough first-dose effects, there was significant protection vs baseline for all devices and equivalence for Clickhaler vs Aerolizer (-0.41; -0.85 to 0.04) and Aerolizer vs pMDI (-0.27; -0.66 to 0.13) but not for Clickhaler vs pMDI (-0.68; -1.12 to -0.23). For trough effects after 2 weeks, there was significant residual protection from baseline and equivalence for Clickhaler vs Aerolizer (-0.32; -0.94 to 0.30), Clickhaler vs pMDI (0.34; -0.96 to 0.27), and Aerolizer vs pMDI (-0.02; -0.57 to 0.52). CONCLUSIONS Formoterol delivered by 3 different inhalers exhibited a significant degree of peak and trough bronchoprotection after single and repeated dosing, with most comparisons being within predefined equivalence limits.
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Affiliation(s)
- Brian J Lipworth
- Department of Medicine and Therapeutics (Asthma and Allergy Research Group), Ninewells Hospital and Medical School, University of Dundee, Dundee, Scotland.
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Dolovich MB, Ahrens RC, Hess DR, Anderson P, Dhand R, Rau JL, Smaldone GC, Guyatt G. Device Selection and Outcomes of Aerosol Therapy: Evidence-Based Guidelines. Chest 2005; 127:335-71. [PMID: 15654001 DOI: 10.1378/chest.127.1.335] [Citation(s) in RCA: 475] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND The proliferation of inhaler devices has resulted in a confusing number of choices for clinicians who are selecting a delivery device for aerosol therapy. There are advantages and disadvantages associated with each device category. Evidence-based guidelines for the selection of the appropriate aerosol delivery device in specific clinical settings are needed. AIM (1) To compare the efficacy and adverse effects of treatment using nebulizers vs pressurized metered-dose inhalers (MDIs) with or without a spacer/holding chamber vs dry powder inhalers (DPIs) as delivery systems for beta-agonists, anticholinergic agents, and corticosteroids for several commonly encountered clinical settings and patient populations, and (2) to provide recommendations to clinicians to aid them in selecting a particular aerosol delivery device for their patients. METHODS A systematic review of pertinent randomized, controlled clinical trials (RCTs) was undertaken using MEDLINE, EmBase, and the Cochrane Library databases. A broad search strategy was chosen, combining terms related to aerosol devices or drugs with the diseases of interest in various patient groups and clinical settings. Only RCTs in which the same drug was administered with different devices were included. RCTs (394 trials) assessing inhaled corticosteroid, beta2-agonist, and anticholinergic agents delivered by an MDI, an MDI with a spacer/holding chamber, a nebulizer, or a DPI were identified for the years 1982 to 2001. A total of 254 outcomes were tabulated. Of the 131 studies that met the eligibility criteria, only 59 (primarily those that tested beta2-agonists) proved to have useable data. RESULTS None of the pooled metaanalyses showed a significant difference between devices in any efficacy outcome in any patient group for each of the clinical settings that was investigated. The adverse effects that were reported were minimal and were related to the increased drug dose that was delivered. Each of the delivery devices provided similar outcomes in patients using the correct technique for inhalation. CONCLUSIONS Devices used for the delivery of bronchodilators and steroids can be equally efficacious. When selecting an aerosol delivery device for patients with asthma and COPD, the following should be considered: device/drug availability; clinical setting; patient age and the ability to use the selected device correctly; device use with multiple medications; cost and reimbursement; drug administration time; convenience in both outpatient and inpatient settings; and physician and patient preference.
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Affiliation(s)
- Myrna B Dolovich
- Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada.
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19
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Ram FSF. Clinical efficacy of inhaler devices containing beta(2)-agonist bronchodilators in the treatment of asthma: cochrane systematic review and meta-analysis of more than 100 randomized, controlled trials. ACTA ACUST UNITED AC 2004; 2:349-65. [PMID: 14720001 DOI: 10.1007/bf03256663] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
BACKGROUND A number of different inhaler devices are available to deliver beta(2)-adrenoceptor agonist (beta(2)-agonist) bronchodilators in asthma. These include hydrofluoroalkane or chlorofluorocarbon (CFC)-free propelled pressurized metered-dose inhalers (pMDIs), many dry powder inhalers and breath-actuated inhalers. OBJECTIVE To determine the clinical efficacy of all available hand-held inhaler devices compared with the standard CFC-containing pMDI for the delivery of short-acting beta(2)-agonist bronchodilators in nonacute asthma in both children and adults. METHODOLOGY A systematic review and meta-analysis was carried out of all available randomized, controlled trials (RCTs) using the standard pMDI compared with any other hand-held inhaler device, delivering short-acting beta(2)-agonist bronchodilators in patients with stable asthma. RESULTS One hundred and eighteen RCTs were included in this review. No clinical differences were found between the standard CFC-containing pMDI and 12 other hand-held inhaler devices for most outcome measures. We found no evidence of clinical differences between studies using either a 1 : 1 (pMDI: another inhaler) or a 2 : 1 dosing ratio. CONCLUSIONS In patients with stable asthma, short-acting beta(2)-agonist bronchodilators in standard CFC-pMDIs are as effective as any other hand-held inhaler device; therefore the cheapest available device that the patient is able to use should always be considered. Pharmaceutical companies should in future submit to regulatory authorities clinical outcome data (as opposed to in vitro data) in support of any dosing schedules greater than 1 : 1 when compared with the standard pMDI. Clinical effectiveness studies that use an intention-to-treat analysis and report more patient-centered outcomes are required.
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Affiliation(s)
- Felix S F Ram
- National Collaborating Centre for Women and Children's Health, Royal College of Obstetricians and Gynaecologists, London, UK
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Abstract
BACKGROUND The inclusion of children with asthma in clinical asthma trials is increasing, including their participation in placebo-controlled trials (PCTs). The objectives of this study are to assess whether children with asthma have been harmed by their participation in PCTs. METHODS Seventy clinical asthma trials involving children published between January 1998 and December 2001 that involved distinct US research populations were identified. Studies were reviewed to determine whether all subjects with more than mild asthma received daily antiinflammatory medication as recommended by national guidelines. Sixty-two clinical asthma trials included data about subject withdrawal and were analyzed for the frequency of asthma exacerbations. RESULTS Forty-five studies were designed as PCTs and did not require that all subjects with more than mild asthma receive antiinflammatory medications. Of 24,953 subjects, 4653 (19%) for whom data are available withdrew from research, and 1247 subjects (9.4%) withdrew from PCTs due to asthma exacerbations compared with 358 subjects (3.1%) in other trials. In PCTs, subjects withdrew more frequently from the placebo arms than the active-treatment arms and did so more frequently because of an asthma exacerbation (667 or 15% vs 580 or 6.5%). Fifty-two studies enrolled both children and adults, although only 1 performed subset analysis of the children. CONCLUSIONS Subjects enrolled in PCTs of asthma have been exposed to unnecessary risks and harms. Clinical asthma trials involving children and adults do not benefit children as a class because they rarely provide subset analysis of children subjects.
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Affiliation(s)
- M Justin Coffey
- Pritzker School of Medicine, University of Chicago, Chicago, Illinois 60637, USA
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Creticos PS, Adams WP, Petty BG, Lewis LD, Singh GJP, Khattignavong AP, Molzon JA, Martinez MN, Lietman PS, Williams RL. A methacholine challenge dose-response study for development of a pharmacodynamic bioequivalence methodology for albuterol metered- dose inhalers. J Allergy Clin Immunol 2002; 110:713-20. [PMID: 12417879 DOI: 10.1067/mai.2002.129036] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND With the expiration of the patent on albuterol metered-dose inhalers (MDIs) in 1989, methods to assess in vivo bioequivalence of generic formulations required investigation. OBJECTIVE In an effort to develop a sensitive method to document bioequivalence, bronchoprovocation with methacholine chloride was used to assess the dose-response relationship of albuterol as delivered by MDI. Sensitivity was assessed in terms of magnitudes of ED(50), the estimated albuterol dose required to achieve 50 % of the fitted maximal value of the pharmacodynamic effect above baseline, and change in response as a function of dose, with emphasis on 1 and 2 actuations. METHODS On separate study days, 15 nonsmokers with mild asthma received randomized nominal albuterol doses of 0 to 576 microg by using specially manufactured MDI canisters. FEV(1) was measured 15 minutes after MDI dosing. Serially increasing doses of methacholine were administered, and FEV(1) was measured after each methacholine dose until a 20 % decrease in FEV(1) (PD(20)) was achieved. RESULTS Mean PD(20) values after use of each of the albuterol-containing MDIs were significantly greater than either mean screening or mean placebo PD(20) values (P <.05). Mean responses and most individual subject responses to 1 and 2 actuations (90 and 180 microg) of albuterol MDI were within the sensitive region of the dose- response curve. The mean estimated ED(50) value on the basis of nonlinear mixed effect modeling was 119.2 microg (range, 33.3-337.1 microg), with an intersubject percentage coefficient of variation of 69.0 %. CONCLUSIONS The methacholine bronchoprovocation model is safe and useful in the study of albuterol MDI dose-response in asthmatic subjects. Bronchoprovocation studies may be used for determination of bioequivalence of multisource albuterol MDI products.
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Affiliation(s)
- Peter S Creticos
- Department of Medicine, Division of Clinical Immunology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Källén A. A Note on Therapeutic Equivalence and Therapeutic Ratio with Application to Studies in Respiratory Diseases. ACTA ACUST UNITED AC 2001. [DOI: 10.1177/009286150103500444] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Ahrens R, Weinberger M. Levalbuterol and racemic albuterol: are there therapeutic differences? J Allergy Clin Immunol 2001; 108:681-4. [PMID: 11692088 DOI: 10.1067/mai.2001.119407] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Ahrens RC, Teresi ME, Han SH, Donnell D, Vanden Burgt JA, Lux CR. Asthma stability after oral prednisone: a clinical model for comparing inhaled steroid potency. Am J Respir Crit Care Med 2001; 164:1138-45. [PMID: 11673199 DOI: 10.1164/ajrccm.164.7.2008112] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Clinical studies comparing the potency of inhaled corticosteroids require steep dose-response slopes (b) and minimal response variability (s), as statistical power is inversely related to the s/b ratio. To evaluate a new study model, we performed a randomized, crossover study of 12 adult asthmatics who required 800 to 2,000 microg of inhaled corticosteroids daily, and calculated s/b for 21 raw clinical outcomes and 36 mathematically derived variables based on these raw outcomes. Each of two 21-d treatment periods was preceded by 4 to 7 d of oral prednisone to maximize asthma control and minimize carry-over of previous inhaled treatment. Treatments were 100 and 800 micron/d of an HFA-134a beclomethasone dipropionate formulation. Assessments included daily home spirometry, histamine challenge, inhaled albuterol use, and asthma symptom scores. Efficacy variables with the greatest power (lowest s/b values) were A.M.FEF25-75, A.M.FEV1, and A.M.PEF, (s/b = 0.46, 0.48, and 0.59). Carry-over between treatment periods was not significant. Crossover study sample size calculations using these ratios yielded samples of 23, 25, and 37 patients, respectively. Otherwise identical parallel studies would require sample sizes of 657, 1,438, and 2,261 patients. These results support the use of a crossover asthma stability model after a short course of oral prednisone as a clinical study model for comparing topical potency of inhaled corticosteroids.
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Affiliation(s)
- R C Ahrens
- Pediatric Allergy/Pulmonary, The University of Iowa, College of Medicine, Iowa City, Iowa 52242-1083, USA.
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Buck H, Parry-Billings M. Discriminating measures of bronchodilator drug efficacy and potency. Br J Clin Pharmacol 2001; 52:245-53. [PMID: 11560556 PMCID: PMC2014546 DOI: 10.1046/j.0306-5251.2001.01450.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2000] [Accepted: 05/04/2001] [Indexed: 11/20/2022] Open
Affiliation(s)
- H Buck
- Innovata Biomed Limited, The Ziggurat, Grosvenor Road, St Albans, Hertfordshire AL1 3HW, UK
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Stewart BA, Ahrens RC, Carrier S, Frosolono M, Lux C, Han SH, Milavetz G. Demonstration of in vivo bioequivalence of a generic albuterol metered-dose inhaler to Ventolin. Chest 2000; 117:714-21. [PMID: 10712996 DOI: 10.1378/chest.117.3.714] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
STUDY OBJECTIVE To use histamine bronchoprovocation and bioassay statistical procedures to evaluate the in vivo bioequivalence of a generic albuterol metered-dose inhaler (MDI). DESIGN A randomized, double-blind, balanced, crossover design was used to determine the potency of each generic albuterol MDI actuation relative to Ventolin (Glaxo Wellcome; Research Triangle Park, NC) administration. One treatment was administered on each of 4 study days. A histamine bronchoprovocation procedure was initiated 1.25 h before and 15 min after administration of the study treatment. PATIENTS Twenty-four nonsmoking subjects with mild-to-moderate asthma were studied (18 to 65 years of age; FEV(1), > 60% of predicted; and provocative concentration of histamine causing a 20% fall in FEV(1) [PC(20)], < or = 8 mg/mL at screening). INTERVENTIONS One and four actuations (90 and 360 microg, respectively) of the generic MDI and of Ventolin MDI. Placebo inhalers were used to maintain blinding of inhaler and doses. MEASUREMENTS AND RESULTS The primary outcome variable was histamine PC(20) measured after study treatment administration. A significant dose-effect relationship was present (p < 0.0001). Deviation from parallelism of the generic and Ventolin dose-response curves (p = 0.95) and differences in overall mean response between the two formulations (p = 0.68) were not significant. Using Finney 2 x 2 bioassay statistical procedures, we estimated that one actuation of the generic albuterol MDI was equivalent to 1.01 puffs of Ventolin (90% confidence interval, 0.69 to 1.50). CONCLUSION The generic albuterol MDI delivers a quantity of albuterol to the beta(2)-receptor site in the lung that is the bioequivalent to Ventolin. Further, this study reinforces the validity of this statistical methodology for determining in vivo bioequivalence.
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Affiliation(s)
- B A Stewart
- Healthcare Professional Associates, Amarillo, TX, USA
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