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1.
Proc Natl Acad Sci U S A ; 118(12)2021 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-33723065

RESUMEN

The ocean is a reservoir for CFC-11, a major ozone-depleting chemical. Anthropogenic production of CFC-11 dramatically decreased in the 1990s under the Montreal Protocol, which stipulated a global phase out of production by 2010. However, studies raise questions about current overall emission levels and indicate unexpected increases of CFC-11 emissions of about 10 Gg ⋅ yr-1 after 2013 (based upon measured atmospheric concentrations and an assumed atmospheric lifetime). These findings heighten the need to understand processes that could affect the CFC-11 lifetime, including ocean fluxes. We evaluate how ocean uptake and release through 2300 affects CFC-11 lifetimes, emission estimates, and the long-term return of CFC-11 from the ocean reservoir. We show that ocean uptake yields a shorter total lifetime and larger inferred emission of atmospheric CFC-11 from 1930 to 2075 compared to estimates using only atmospheric processes. Ocean flux changes over time result in small but not completely negligible effects on the calculated unexpected emissions change (decreasing it by 0.4 ± 0.3 Gg ⋅ yr-1). Moreover, it is expected that the ocean will eventually become a source of CFC-11, increasing its total lifetime thereafter. Ocean outgassing should produce detectable increases in global atmospheric CFC-11 abundances by the mid-2100s, with emission of around 0.5 Gg ⋅ yr-1; this should not be confused with illicit production at that time. An illustrative model projection suggests that climate change is expected to make the ocean a weaker reservoir for CFC-11, advancing the detectable change in the global atmospheric mixing ratio by about 5 yr.


Asunto(s)
Atmósfera , Clorofluorocarburos/efectos adversos , Contaminantes Ambientales/efectos adversos , Océanos y Mares , Ozono , Cambio Climático , Monitoreo del Ambiente , Modelos Teóricos
3.
Fed Regist ; 81(207): 74298-302, 2016 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-27905700

RESUMEN

The Food and Drug Administration (FDA, the Agency, or we) is amending its regulation on uses of ozone-depleting substances (ODSs), including chlorofluorocarbons (CFCs), to remove the designation for certain products as "essential uses" under the Clean Air Act. Essential-use products are exempt from the ban by FDA on the use of CFCs and other ODS propellants in FDA-regulated products and from the ban by the Environmental Protection Agency (EPA) on the use of ODSs in pressurized dispensers. The products that will no longer constitute an essential use are: Sterile aerosol talc administered intrapleurally by thoracoscopy for human use and metered-dose atropine sulfate aerosol human drugs administered by oral inhalation. FDA is taking this action because alternative products that do not use ODSs are now available and because these products are no longer being marketed in versions that contain ODSs.


Asunto(s)
Propelentes de Aerosoles/efectos adversos , Contaminantes Atmosféricos/efectos adversos , Clorofluorocarburos/efectos adversos , Pérdida de Ozono/legislación & jurisprudencia , United States Food and Drug Administration/legislación & jurisprudencia , Propelentes de Aerosoles/uso terapéutico , Atropina/uso terapéutico , Clorofluorocarburos/uso terapéutico , Humanos , Pérdida de Ozono/prevención & control , Talco/uso terapéutico , Estados Unidos
4.
Thorax ; 67(12): 1028-31, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23019254

RESUMEN

The Montreal Protocol was signed 25 years ago. As a result, the irreversible destruction of the ozone layer was prevented. However, stratospheric ozone will not recover completely until 2060 and the consequent epidemic in skin cancer cases will persist until 2100. Many millions of patients with asthma and chronic obstructive pulmonary disease have safely switched from chlorofluorocarbon (CFC)-powered metered-dose inhalers (MDIs) to either hydrofluorocarbon (HFC) or DPIs. China will be the last country to phase out CFCs by 2016. HFCs are global warming gases which will be controlled in the near future. HFCs in MDIs may be phased out over the next 10-20 years.


Asunto(s)
Propelentes de Aerosoles/efectos adversos , Antiasmáticos/administración & dosificación , Asma/tratamiento farmacológico , Clorofluorocarburos/efectos adversos , Contaminación Ambiental/legislación & jurisprudencia , Salud Global , Inhaladores de Dosis Medida , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Ozono Estratosférico , Propelentes de Aerosoles/química , Antiasmáticos/química , Asma/epidemiología , Clorofluorocarburos/química , Humanos , Cooperación Internacional , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Neoplasias Cutáneas/epidemiología
5.
Fed Regist ; 75(71): 19213-41, 2010 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-20391646

RESUMEN

The Food and Drug Administration (FDA), after consultation with the Environmental Protection Agency (EPA), is amending FDA's regulation on the use of ozone-depleting substances (ODSs) in self-pressurized containers to remove the essential-use designations for flunisolide, triamcinolone, metaproterenol, pirbuterol, albuterol and ipratropium in combination, cromolyn, and nedocromil used in oral pressurized metered-dose inhalers (MDIs). The Clean Air Act requires FDA, in consultation with the EPA, to determine whether an FDA-regulated product that releases an ODS is an essential use of the ODS. FDA has concluded that there are no substantial technical barriers to formulating flunisolide, triamcinolone, metaproterenol, pirbuterol, albuterol and ipratropium in combination, cromolyn, and nedocromil as products that do not release ODSs, and therefore they will no longer be essential uses of ODSs as of the effective dates of this rule. MDIs for these active moieties containing an ODS may not be marketed after the relevant effective date.


Asunto(s)
Contaminantes Atmosféricos/clasificación , Contaminación del Aire/prevención & control , Antiasmáticos/clasificación , Broncodilatadores/clasificación , Clorofluorocarburos/efectos adversos , Nebulizadores y Vaporizadores/clasificación , Contaminantes Atmosféricos/efectos adversos , Albuterol/administración & dosificación , Albuterol/uso terapéutico , Antiasmáticos/administración & dosificación , Antiasmáticos/uso terapéutico , Asma/tratamiento farmacológico , Atmósfera , Broncodilatadores/administración & dosificación , Broncodilatadores/uso terapéutico , Química Farmacéutica , Clorofluorocarburos/administración & dosificación , Clorofluorocarburos/clasificación , Clorofluorocarburos/uso terapéutico , Costos de los Medicamentos , Quimioterapia Combinada , Fluocinolona Acetonida/administración & dosificación , Fluocinolona Acetonida/análogos & derivados , Fluocinolona Acetonida/uso terapéutico , Humanos , Ipratropio/administración & dosificación , Ipratropio/uso terapéutico , Metaproterenol/administración & dosificación , Metaproterenol/uso terapéutico , Ozono , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Triamcinolona/administración & dosificación , Triamcinolona/uso terapéutico , Estados Unidos
6.
Pharmaceut Med ; 34(3): 191-199, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32500439

RESUMEN

Asthma and chronic obstructive pulmonary disease (COPD) are amongst the most common chronic diseases worldwide, and are largely preventable by improving the quality of the air we breathe. The most commonly deployed treatment, the metered dose inhaler (MDI), uses hydrofluorocarbon propellants, which are powerful greenhouse gases that contribute disproportionately to the climate crisis. Alternative treatment strategies are required if we are to avoid contributing to the worst effects of climate change. These strategies include promoting non-pharmacological therapies like smoking cessation and pulmonary rehabilitation; empowering patients to gain better disease control through written management plans and encouraging preventer, rather than reliever therapies. Pharmacological strategies include: improving inhaler technique and spacer use; minimising propellant release by using smaller volume MDIs and simpler dosing regimes; dose counters to prevent waste; switching to low global warming potential inhalers; and inhaler recycling. There are also opportunities to improve disease control alongside reduced greenhouse gas emissions, including better matching of patients' devices to inhaler technique rather than defaulting to MDIs, stopping unnecessary inhaled steroids in COPD and maintenance and reliever therapy in asthma. New, lower global warming potential propellants are on the horizon, and their introduction could offer a golden opportunity to enhance MDIs usability and sustainability by making them refillable, integrating whistles to optimise inhalation technique, adding integrated caps, optimising materials for recycling and adding dose counters to all MDIs.


Asunto(s)
Propelentes de Aerosoles/efectos adversos , Clorofluorocarburos/efectos adversos , Efecto Invernadero , Gases de Efecto Invernadero/efectos adversos , Inhaladores de Dosis Medida/efectos adversos , Preparaciones Farmacéuticas/administración & dosificación , Desarrollo Sostenible , Administración por Inhalación , Diseño de Equipo , Equipo Reutilizado , Humanos , Reciclaje
7.
JBJS Case Connect ; 10(2): e0107, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32649084

RESUMEN

CASE: A 72-year-old man presented for evaluation of bony prominences over extremities. Radiographic imaging demonstrated masses of varying sizes extending from the cortical surfaces without medullary continuity. The patient had a history of Freon inhalation abuse and was diagnosed with skeletal fluorosis due to elevated serum fluoride levels. He underwent an uncomplicated excision of a left fibular mass that was threatening skin breakdown. CONCLUSIONS: This is the first reported surgical case of skeletal fluorosis demonstrating continued enlargement of bony prominences throughout the body. Skeletal fluorosis not only causes diffuse mineralization but may also lead to protruding lesions throughout the body.


Asunto(s)
Clorofluorocarburos/efectos adversos , Osteosclerosis/cirugía , Trastornos Relacionados con Sustancias/cirugía , Anciano , Humanos , Masculino , Procedimientos Ortopédicos , Osteosclerosis/inducido químicamente , Osteosclerosis/diagnóstico por imagen , Radiografía , Trastornos Relacionados con Sustancias/diagnóstico por imagen , Trastornos Relacionados con Sustancias/etiología
11.
Fed Regist ; 70(63): 17167-92, 2005 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-15806739

RESUMEN

The Food and Drug Administration (FDA) is amending its regulation on the use of ozone-depleting substances (ODSs) in self-pressurized containers to remove the essential-use designations for albuterol used in oral pressurized metered-dose inhalers (MDIs). Under the Clean Air Act, FDA, in consultation with the Environmental Protection Agency (EPA), is required to determine whether an FDA-regulated product that releases an ODS is an essential use of the ODS. Two albuterol MDIs that do not use an ODS have been marketed for more than 3 years. FDA has determined that the two non-ODS MDIs will be satisfactory alternatives to albuterol MDIs containing ODSs and is removing the essential-use designation for albuterol MDIs as of December 31, 2008. Albuterol MDIs containing an ODS cannot be marketed after this date.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Contaminación del Aire/prevención & control , Albuterol/clasificación , Clorofluorocarburos/efectos adversos , Inhaladores de Dosis Medida/efectos adversos , Ozono , Agonistas Adrenérgicos beta/clasificación , Contaminación del Aire/legislación & jurisprudencia , Albuterol/uso terapéutico , Asma/tratamiento farmacológico , Costos y Análisis de Costo , Humanos , Medicaid/economía , Medicaid/legislación & jurisprudencia , Medicare/economía , Medicare/legislación & jurisprudencia , Estados Unidos , United States Environmental Protection Agency
12.
Environ Health Perspect ; 112(11): A632-5, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15289184

RESUMEN

As the 2010 phaseout date for chlorofluorocarbons draws nearer, materials engineers are working to find replacements for these ozone-depleting chemicals in the production of plastics and other products. One team of engineers is focusing on a combination of two low-cost and environmentally benign substances--supercritical carbon dioxide and clay nanoparticles--to meet these needs. The result is a strong yet lightweight alternative that retains all the beneficial qualities of solid plastic.


Asunto(s)
Industria Química , Ambiente , Nanotecnología/tendencias , Plásticos , Silicatos de Aluminio , Dióxido de Carbono , Clorofluorocarburos/efectos adversos , Arcilla , Retardadores de Llama , Efecto Invernadero , Ensayo de Materiales
13.
Chest ; 120(4): 1253-61, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11591569

RESUMEN

STUDY OBJECTIVE: To compare the efficacy and safety of ipratropium bromide reformulated with the chlorofluorocarbon (CFC)-free propellant hydrofluoroalkane (HFA)-134a (ipratropium bromide HFA) to that of the marketed ipratropium bromide inhalation aerosol (containing CFC) in patients with COPD. DESIGN: This was a randomized, double-blind, parallel-group, placebo-controlled, multicenter trial. The primary efficacy parameter was acute bronchodilator response. The primary end points were peak change in FEV(1) from baseline and area under the response-time curve. SETTING: Thirty-one clinical centers in the United States participated in this project. PATIENTS: A total of 507 patients with moderate-to-severe COPD were randomized, and 444 patients completed the trial. INTERVENTIONS: Twelve weeks of treatment four times daily with one of the following: ipratropium bromide HFA, 42 microg; ipratropium bromide HFA, 84 microg; HFA placebo; ipratropium bromide inhalation aerosol, 42 microg; or CFC placebo. MEASUREMENTS AND RESULTS: Patients in all active treatment groups had significant bronchodilator responses as shown by increases in mean FEV(1) from baseline of at least 15%. Bronchodilator response in all active treatment groups was also significantly more than their respective placebo treatments based on FEV(1), area under the time-response curve from 0 to 6 h, and peak response. FVC results were similar to those seen with FEV(1). There were no significant differences in adverse events, laboratory findings, or ECG findings among the treatment groups. CONCLUSIONS: Ipratropium bromide HFA, 42 and mgr;g, provided bronchodilation comparable to the marketed ipratropium bromide CFC, 42 and mgr;g, over 12 weeks of regular use.


Asunto(s)
Propelentes de Aerosoles , Hidrocarburos Fluorados , Ipratropio/administración & dosificación , Nebulizadores y Vaporizadores , Adulto , Propelentes de Aerosoles/administración & dosificación , Anciano , Anciano de 80 o más Años , Resistencia de las Vías Respiratorias/efectos de los fármacos , Clorofluorocarburos/efectos adversos , Método Doble Ciego , Femenino , Volumen Espiratorio Forzado/efectos de los fármacos , Humanos , Hidrocarburos Fluorados/efectos adversos , Ipratropio/efectos adversos , Masculino , Persona de Mediana Edad
14.
Chest ; 115(4): 945-51, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10208190

RESUMEN

BACKGROUND: Chlorofluorocarbons (CFCs) used as propellants in metered-dose inhalers deplete stratospheric ozone, which results in serious public health concerns. Albuterol has been reformulated in the non-ozone-depleting propellant, hydrofluoroalkane-134a (HFA albuterol). OBJECTIVES: The primary objective was to compare the safety of HFA albuterol to an albuterol product formulated in chlorofluorocarbon propellants (CFC albuterol) during 1 year of treatment in asthmatics. Bronchodilator efficacy of the two products was assessed as a secondary objective. METHODS: The results from two open-label, parallel-group trials of similar design in asthmatics requiring short-acting beta-agonists for symptom control were combined. Patients took two puffs bid of either HFA albuterol or CFC albuterol for 1 year. Additional puffs of study drug were allowed as needed to control asthma symptoms. Adverse events were recorded at clinic visits. Patients self-administered study drug at quarterly visits and underwent serial spirometry during a 6-h period postdose. Bronchodilator efficacy variables, based on FEV1 response to study drug, were proportion of responders, time to onset of effect, peak percent change, time to peak effect, duration of effect, and area under the curve. Differences between products and changes over time in efficacy variables were assessed using an analysis of variance model. Regression analyses with FEV1 as a covariate were performed post-hoc to analyze changes in bronchodilator efficacy over time. RESULTS: Demographic and baseline characteristics were similar for patients receiving HFA albuterol (n = 337) and CFC albuterol (n = 132). Total reported adverse events were similar for the two treatments. Differences in only four individual adverse events were noted: the HFA albuterol group reported more gastroenteritis and dizziness; the CFC albuterol group reported more epistaxis and expectoration. Adverse events attributed to study drug use were infrequent. No serious adverse events were related to study drug use. Predose FEV1 at quarterly visits increased to a small extent in both groups from month 0 to month 12. The bronchodilator efficacy of HFA albuterol was comparable to that of CFC albuterol at the quarterly visits, but decreased from baseline for both products over the 12 months of treatment. Use of inhaled corticosteroids, nasal corticosteroids, or theophylline did not explain the increase in predose FEV1 over time and did not protect patients from developing reduced bronchodilator efficacy by month 12. The change in predose FEV1 did not entirely account for the reduced bronchodilator efficacy over time. CONCLUSIONS: HFA albuterol has a safety profile similar to that of CFC albuterol during chronic, scheduled use, and both drugs are well tolerated. HFA albuterol and CFC albuterol provided comparable bronchodilator efficacy, but bronchodilator efficacy decreased for both products with 1 year of use.


Asunto(s)
Agonistas Adrenérgicos beta/administración & dosificación , Propelentes de Aerosoles , Albuterol/administración & dosificación , Asma/tratamiento farmacológico , Broncodilatadores/administración & dosificación , Hidrocarburos Fluorados/administración & dosificación , Administración por Inhalación , Agonistas Adrenérgicos beta/efectos adversos , Adulto , Propelentes de Aerosoles/efectos adversos , Aerosoles , Albuterol/efectos adversos , Asma/fisiopatología , Broncodilatadores/efectos adversos , Clorofluorocarburos/efectos adversos , Femenino , Volumen Espiratorio Forzado , Humanos , Hidrocarburos Fluorados/efectos adversos , Masculino
15.
Respir Med ; 94 Suppl B: S17-21, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10919681

RESUMEN

This randomized, double-blind, parallel-group study compared the efficacy and tolerability of as-required salbutamol 100 microg administered from either a chlorofluorocarbon (CFC) pressurized metered dose inhaler (pMDI; Ventolin) or from a non-CFC hydrofluoroalkane (HFA) 134a pMDI (Ventolin CFC-free) in patients with mild to moderate asthma. All patients (n = 423) continued with their standard asthma therapy, and recorded their daily use of study medication, morning and evening peak expiratory flow (PEF) and symptom scores, throughout the 4-week treatment period. Clinic lung function was measured at 2-week intervals. The median daily use of inhaled study medication remained constant at four actuations per day throughout the study in both treatment groups and statistical analysis indicated that the two formulations were equivalent. Small improvements in both treatment groups were reported in mean morning and evening PEF, clinic forced expiratory volume in 1 sec and clinic PEF and there were no significant differences between the two groups. Both formulations were well tolerated. This study indicates that as-required salbutamol 100 microg administered via a HFA 134a pMDI is as effective and safe as the currently available CFC-propelled formulation.


Asunto(s)
Propelentes de Aerosoles/farmacocinética , Albuterol/administración & dosificación , Asma/tratamiento farmacológico , Broncodilatadores/administración & dosificación , Hidrocarburos Fluorados/farmacocinética , Administración por Inhalación , Adolescente , Adulto , Propelentes de Aerosoles/efectos adversos , Anciano , Anciano de 80 o más Años , Clorofluorocarburos/efectos adversos , Clorofluorocarburos/farmacocinética , Método Doble Ciego , Femenino , Volumen Espiratorio Forzado/fisiología , Humanos , Hidrocarburos Fluorados/efectos adversos , Masculino , Persona de Mediana Edad , Ápice del Flujo Espiratorio/fisiología , Equivalencia Terapéutica , Resultado del Tratamiento
16.
Respir Med ; 94 Suppl B: S35-41, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10919684

RESUMEN

This multi-national, double-blind, randomized, parallel-group study compared the efficacy and tolerability of fluticasone propionate 500 microg twice daily propelled either by the non-chlorofluorocarbon (CFC) propellant, hydrofluoroalkane (HFA) 134a, or the CFC propellants 11 and 12 used in the established pressurized metered dose inhaler (pMDI). The study period was 12 months and involved 412 subjects with moderate to severe asthma (HFA 134a pMDI: n = 203; CFC pMDI: n = 209). For the first 3 months, subjects kept a daily record card and attended the clinic every 4 weeks. Thereafter, they kept daily diaries for 2 weeks before each clinic assessment, which were performed at the end of 6, 9 and 12 months. Mean morning peak expiratory flow (PEF) increased during the first week in both treatment groups. By the end of week 12 the adjusted mean increase from baseline in morning PEF was 21 and 23 l min(-1) in the HFA 134a and CFC pMDI groups, respectively, and this increase was maintained throughout the 12-month study period. Similar improvements were detected in other diary card parameters and in clinic lung function measurements. The two groups were shown to be clinically equivalent in terms of all efficacy variables and there were no differences in tolerability. There were few reports of low serum cortisol levels during the 12-month study period, and serum cortisol levels were similar at baseline and after 12 weeks and 12 months of treatment in the two groups. In conclusion, the new HFA 134a fluticasone propionate pMDI is as effective and safe as the established CFC fluticasone propionate pMDI when used at a dosage of 1 mg day(-1).


Asunto(s)
Propelentes de Aerosoles/farmacocinética , Androstadienos/administración & dosificación , Antiasmáticos/administración & dosificación , Asma/tratamiento farmacológico , Hidrocarburos Fluorados/farmacocinética , Administración por Inhalación , Adolescente , Adulto , Propelentes de Aerosoles/efectos adversos , Anciano , Clorofluorocarburos/efectos adversos , Clorofluorocarburos/farmacocinética , Método Doble Ciego , Femenino , Fluticasona , Volumen Espiratorio Forzado/fisiología , Humanos , Hidrocarburos Fluorados/efectos adversos , Hidrocortisona/sangre , Masculino , Persona de Mediana Edad , Ápice del Flujo Espiratorio/fisiología , Equivalencia Terapéutica , Resultado del Tratamiento
17.
Respir Med ; 94 Suppl B: S29-34, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10919683

RESUMEN

This study compared the efficacy and safety of the fluticasone propionate 125 microg pressurized metered dose inhaler (pMDI) propelled by either hydrofluoroalkane (HFA) 134a or chlorofluorocarbon (CFC) propellants, in adult patients with asthma. HFA 134a is a non-ozone depleting propellant used as a replacement for the CFC propellants 11 and 12 which are being phased out in accordance with the Montreal Protocol. Three hundred and eighty patients with mild to moderate asthma and 'room for improvement' in their treatment were randomized to receive fluticasone propionate 250 microg twice daily via pMDIs propelled by either CFC propellants 11 and 12 (n = 195) or HFA 134a (n = 185). Fluticasone propionate significantly improved lung function over the 4-week treatment period in both treatment groups. The improvement in mean morning peak expiratory flow (PEF) after 7 days of treatment was approximately 12 l min(-1) in both groups, rising to approximately 22 l min(-1) at the end of the 4-week treatment period. The adjusted mean difference between the two formulations over weeks 1-4 was -1 l min(-1) (90% confidence interval: -7, 5 l min(-1)), confirming their equivalence. Clinical comparability was also demonstrated with respect to secondary efficacy variables, including daily symptom scores, evening PEF and clinic visit expiratory measurements. There were no clinically relevant differences in adverse events or serum cortisol levels between the two groups. The fluticasone propionate 125 microg HFA 134a pMDI is an effective and well tolerated product and is a suitable replacement for the fluticasone propionate 125 microg CFC pMDI at a microgram equivalent dose.


Asunto(s)
Propelentes de Aerosoles/farmacocinética , Androstadienos/administración & dosificación , Antiasmáticos/administración & dosificación , Asma/tratamiento farmacológico , Hidrocarburos Fluorados/farmacocinética , Administración por Inhalación , Adolescente , Adulto , Propelentes de Aerosoles/efectos adversos , Anciano , Anciano de 80 o más Años , Clorofluorocarburos/efectos adversos , Clorofluorocarburos/farmacocinética , Método Doble Ciego , Femenino , Fluticasona , Volumen Espiratorio Forzado/fisiología , Humanos , Hidrocarburos Fluorados/efectos adversos , Hidrocortisona/sangre , Masculino , Persona de Mediana Edad , Ápice del Flujo Espiratorio/fisiología , Equivalencia Terapéutica , Resultado del Tratamiento
18.
Respir Med ; 94 Suppl B: S42-50, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10919685

RESUMEN

A randomized, double-blind, cross-over study was conducted to assess the efficacy and safety of fluticasone propionate 1 mg twice daily administered via a pressurized metered dose inhaler (pMDI) containing the new non-chlorofluorocarbon (CFC) propellant (HFA 134a), or the established CFC propellants 11 and 12 in patients with severe asthma. The study comprised a 2-week run-in period followed by two 6-week treatment periods, with no washout period in between. One hundred and nineteen symptomatic adult patients with severe asthma, who were receiving inhaled beclomethasone 2-4 mg day(-1) or equivalent, were randomized to treatment. Patients were randomized to one of two sequence groups (sequence 1: HFA 134a pMDI then CFC pMDI or sequence 2: CFC pMDI then HFA 134a pMDI). The sequence groups differed with respect to mean peak expiratory flow (PEF) at baseline; however, the magnitude of the increase in PEF from baseline during treatment was similar in the two sequence groups. Mean PEF at baseline was 334 l min(-1) in sequence group 1 (HFA 134a-->CFC pMDI) and this increased to 357 l min(-1) and 366 l min(-1) during treatment with the HFA 134a and CFC pMDI, respectively. In sequence group 2 (CFC-->HFA 134a pMDI) mean PEF at baseline was 297 l min(-1) and this increased to 336 l min(-1) and 328 l min(-1) during treatment with the HFA 134a and CFC pMDI, respectively. Based on an overall analysis of the two treatment groups at week 6, equivalence was demonstrated; the mean treatment difference (HFA 134a-CFC pMDI) in morning PEF was 0 l min(-1) (90% confidence interval (CI), for difference between groups: -7, 6 l min(-1)). There was a comparable improvement in secondary efficacy variables, including clinic lung function measurements, in the two treatment groups. The incidence and type of most adverse events were similar in the two treatment groups. There was no difference in the adjusted geometric mean morning serum cortisol levels after treatment with the HFA 134a and CFC pMDI. Therefore, the fluticasone propionate HFA 134a pMDI constitutes a suitable replacement for the established CFC pMDI at a microgram equivalent dose.


Asunto(s)
Propelentes de Aerosoles/farmacocinética , Androstadienos/administración & dosificación , Antiasmáticos/administración & dosificación , Asma/tratamiento farmacológico , Enfermedad Crónica/tratamiento farmacológico , Hidrocarburos Fluorados/farmacocinética , Administración por Inhalación , Adolescente , Adulto , Propelentes de Aerosoles/efectos adversos , Anciano , Clorofluorocarburos/efectos adversos , Clorofluorocarburos/farmacocinética , Estudios Cruzados , Método Doble Ciego , Femenino , Fluticasona , Volumen Espiratorio Forzado/fisiología , Humanos , Hidrocarburos Fluorados/efectos adversos , Hidrocortisona/sangre , Masculino , Persona de Mediana Edad , Ápice del Flujo Espiratorio/fisiología , Equivalencia Terapéutica , Resultado del Tratamiento
19.
Respir Med ; 92 Suppl A: 33-9, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9850361

RESUMEN

Herein we assess the safety of an inhaled formulation of beclomethasone dipropionate (BDP) which uses the propellant hydrofluoroalkane-134a (HFA) for the treatment of asthma. Acute local tolerability (as assessed by the incidence of cough and mean forced expiratory volume after 1 s inhalation) was similar for both BDP and placebo formulated in either chlorofluorocarbon (CFC) or HFA propellants. A total of 43 patients were treated with HFA-BDP (0, 200, 400 or 800 micrograms day-1) or CFC-BDP (800 micrograms day-1) for 14 days and their 24 h urinary free cortisol (UFC) excretion and response to cosyntropin stimulation were measured. There was no difference in UFC between any of the doses of HFA-BDP and CFC-BDP. Adrenal responsiveness to cosyntropin stimulation was normal in all but one patient. Two large 12 week phase III trials compared HFA-placebo, HFA-BDP 400 micrograms day-1 and CFC-BDP 800 micrograms day-1 (n = 347), and HFA-BDP 800 micrograms day-1 and CFC-BDP 1500 micrograms day-1 (n = 233). For HFA-BDP at either dose, CFC-BDP 800 micrograms day-1 and HFA-placebo, the number of patients with morning plasma cortisol concentrations below normal was less than 4.4% but was 14.6% for CFC-BDP 1500 micrograms day-1. The incidence of adverse events was lower in the HFA-BDP groups than in the CFC-BDP groups (P = 0.012). The data indicate that, at doses of up to 800 micrograms day-1, HFA-BDP is at least as well tolerated as CFC-BDP. Other studies have found that equivalent efficacy is reached at lower doses of HFA-BDP than CFC-BDP. Equivalent efficacy at a lower dose and equivalent safety at the same dose imply that HFA-BDP may have a more favourable risk: benefit ratio than CFC-BDP when used at the recommended lower doses.


Asunto(s)
Propelentes de Aerosoles/efectos adversos , Tos/inducido químicamente , Hidrocarburos Fluorados/efectos adversos , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Administración por Inhalación , Adolescente , Adulto , Anciano , Antiinflamatorios/administración & dosificación , Antiinflamatorios/uso terapéutico , Asma/sangre , Asma/tratamiento farmacológico , Asma/orina , Beclometasona/administración & dosificación , Beclometasona/uso terapéutico , Clorofluorocarburos/efectos adversos , Cosintropina , Estudios Cruzados , Esquema de Medicación , Humanos , Hidrocortisona/sangre , Hidrocortisona/orina , Persona de Mediana Edad
20.
Respir Med ; 94(1): 57-63, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10714480

RESUMEN

Chlorofluorocarbon (CFC)-containing inhalers for use in the treatment of asthma are to be phased out under the terms of the Montreal Protocol (1). In this multi-centre, randomized, double-blind study, the therapeutic equivalence of two formulations of beclomethasone dipropionate (BDP) containing CFC or non-CFC (HFA134a) propellant, both delivered via the Easibreathe (Norton Healthcare Ltd, London, U.K.) inhaler, was determined in 229 asthmatic children. Each child received 100 microg doses of BDP (containing either CFC or HFA propellant) twice daily for 12 weeks. Both CFC and HFA formulations produced statistically and clinically significant improvements in patient's lung function and symptom scores when administered via the Easibreathe inhaler. The improvements in mean morning peak expiratory flow (PEF) were 41 l min(-1) and 34 l min(-1) for the BDP-HFA and BDP-CFC products respectively (P<0.001) and for mean evening PEF the improvements were 38 l min(-1) and 38 l min(-1), respectively (P<0.001). Similar findings were demonstrated for the other efficacy parameters. The two formulations were statistically equivalent with respect to efficacy. For mean morning PEF the estimated treatment difference (BDP-CFC/BDP-HFA ratio) was 102.6% (95% CI 99.1, 106.2). Similar equivalence was shown for the other efficacy parameters. Both products were well tolerated, with no difference in the adverse event profiles, effects on 24 h urinary cortisol or Candida colonisation. This study demonstrates that the new formulation of BDP with HFA-134a propellant is equivalent to and directly substitutable for BDP with the older CFC propellant in a dose for dose manner. This should enable a seamless transition from one product to the other when CFC containing products are eventually phased out. In addition this study has also shown that the Easibreathe inhaler is an effective delivery system for use with inhaled products for the treatment of asthma in children.


Asunto(s)
Antiasmáticos/administración & dosificación , Asma/tratamiento farmacológico , Beclometasona/administración & dosificación , Propelentes de Aerosoles/administración & dosificación , Propelentes de Aerosoles/efectos adversos , Propelentes de Aerosoles/farmacocinética , Antiasmáticos/efectos adversos , Antiasmáticos/farmacocinética , Asma/orina , Beclometasona/efectos adversos , Beclometasona/farmacocinética , Niño , Clorofluorocarburos/administración & dosificación , Clorofluorocarburos/efectos adversos , Clorofluorocarburos/farmacocinética , Método Doble Ciego , Femenino , Humanos , Hidrocarburos Fluorados/administración & dosificación , Hidrocarburos Fluorados/efectos adversos , Hidrocarburos Fluorados/farmacocinética , Hidrocortisona/orina , Masculino , Nebulizadores y Vaporizadores , Equivalencia Terapéutica , Resultado del Tratamiento
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