Pharmacokinetics and Pharacodynamics of GW642444 in Paedetric Subjects

Study Overview
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Brief Summary
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This study will investigate the effect of dosing paedeatric asthmatic subjects with GW642444, an orally inhaled long-acting agonist of the β2-adrenoceptor.

Detailed Description
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This study will investigate the effect of dosing with 25 μg GW642444, an orally inhaled long-acting agonist of the β2-adrenoceptor, in asthmatic subjects aged 5 to 11. GW642444 is currently under development as the long-acting beta-agonist component of a combination product containing an inhaled corticosteroid and a longacting beta-agonist. Subjects will receive a single dose via a novel dry powder inhaler, then 7 days once-daily repeat dosing following a washout period. The study will be a randomized two-way crossover, with a placebo control. Approximately 26 subjects will be recruited to this study, with the aim that 20 will complete the study. Safety, tolerability, pharmacokinetics and glucose and potassium levels will be investigated.

Official Title
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A Randomized, Double-blind, Placebo-controlled, Two-way Crossover 7-day Study to Investigate the Safety, Tolerability, Pharmacodynamics and Pharmacokinetics of Repeat Dose Inhaled GW642444 25 μg (Micrograms) in Children Aged 5-11 Years With Persistent Asthma.

Conditions
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Asthma

Intervention / Treatment
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* Drug: GW642444
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male and pre-menarchial female subjects aged 5-11 years on the last planned treatment day are eligible for this study. Pre-menarchial females are defined as any female who has yet to begin menses and is considered Tanner Stage 2 or less. Diagnosis of asthma at least 6 months prior to screening. Patients must be controlled on their existing asthma treatment at Screening as defined by a Childhood Asthma Control Test score of >19 and PEF (Peak Expiratory Flow) >75 % predicted. Subjects must be taking a stable regimen of fluticasone propionate (≤200 μg (micrograms) twice daily or equivalent) and short acting beta-agonist inhaler on an as-need basis for at least 4 weeks prior to screening. Apart from asthma, eczema and rhinitis, subjects should be healthy and suffer from no other significant medical conditions. Subjects must weigh at least 15 kg (kilograms). Subjects must demonstrate ability to accept and effectively use the GW642444 device using the demonstration kits provided to the site. The subject and parent or guardian are able to understand and comply with protocol requirements, instructions, and protocol-stated restrictions. The parent or guardian must have the ability to read, write and record diary information collected throughout the study. The parent or guardian must also have the ability to manage study drug administration and PEF assessments. At least one parent or guardian has signed and dated the written informed consent prior to admission to the study. This will be accompanied by informed assent from the subject. Exclusion Criteria: Subjects currently receiving (or have received within 4 weeks of screening) any of the following asthma therapies: theophyllines, long-acting inhaled beta-agonists, oral beta-agonist. Subjects who have changed their asthma medication within 4 weeks of screening. Clinical visual evidence of oral candidiasis at screening. Any clinically relevant abnormality identified on the screening medical assessment Any medical condition or circumstance making the subject unsuitable for participation in the study (e.g. history of life-threatening asthma) Asthma exacerbation requiring systemic corticosteroids (oral, intramuscular, intravenous) or Emergency Room attendance within 3 months or asthma exacerbation requiring hospitalization within 6 months prior to the screening visit. Culture-documented or suspected bacterial or viral infection of the upper or lower respiratory tract which is not resolved within 4 weeks of the screening visit. Any adverse reaction including immediate or delayed hypersensitivity to any betaagonist therapy. Known or suspected sensitivity to the constituents of the novel dry powder inhaler (i.e., lactose or magnesium stearate), for example, history of severe milk protein allergy. The parent or guardian has history of psychiatric disease, intellectual deficiency, substance abuse, or other condition (e.g., inability to read, comprehend or write) which will limit the validity of consent to participate in this study. A subject will not be eligible for this study if he/she is an immediate family member of the participating Investigator, sub-Investigator, study coordinator, or employee of the participating Investigator. Children who are wards of the state or government. Evidence of clinically significant abnormality in the 12-lead ECG (electrocardiogram) at Screening

Ages Eligible for Study
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Minimum Age: 5 Years
Maximum Age: 11 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: COHORT 1 (RANDOMISATION AB or BA)<br>8-11 years old; Subjects will be assigned to receive GW642444 25μg or matching placebo (in a 1:1 ratio) in an AB or BA (A= GW64244, B= Placebo) sequence. Following randomisation (AB or BA) subjects will receive a single dose treatment, followed by 7 day washout period. This will then be followed by a repeat dose session of the same treatment (Day 8 and Day 14 in house, Days 9-13 at home). Each subject will then complete the same sequence for the alternative treatment in the second session. There will be a washout period of at least 7 days between the treatment periods. | Drug: GW642444<br>* GW642444 25 μg; Novel dry powder inhaler<br>Drug: Placebo<br>* Matching placebo; Novel dry powder inhaler<br>|
| Active Comparator: COHORT 2 (RANDOMISATION AB or BA)<br>5-7 years old. Subjects will be assigned to receive GW642444 25μg or matching placebo (in a 1:1 ratio) in an AB or BA (A= GW64244, B= Placebo) sequence. Following randomisation (AB or BA) subjects will receive a single dose treatment, followed by 7 day washout period. This will then be followed by a repeat dose session of the same treatment (Day 8 and Day 14 in house, Days 9-13 at home). Each subject will then complete the same sequence for the alternative treatment in the second session. There will be a washout period of at least 7 days between the treatment periods. | Drug: GW642444<br>* GW642444 25 μg; Novel dry powder inhaler<br>Drug: Placebo<br>* Matching placebo; Novel dry powder inhaler<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Weighted Mean Heart Rate at Day 1 and Day 14 of the Respective Treatment Period | Heart rate (HR) was measured at Day 1 and Day 14 of the respective treatment period. hr=hour. Weighted means were derived using the linear trapezoidal rule. Actual relative times were used for the calculation except where actual times were missing. If any actual times were missing, planned relative times were used for these observations. For 0-8 hr parameters, treatment, period, participant Baseline, and period Baseline were fitted as fixed effects, and participant was fitted as a random effect. For 0-2 hr parameters, treatment, period, day (1 and 14), participant Baseline, period Baseline, and treatment*day interaction were fitted as fixed effects, and participant was fitted as a random effect. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg (n=28). | Day 1 and Day 14 of the respective treatment period (up to Study Day 49) | 
| Number of Participants With Any Adverse Event (AE) or Any Serious Adverse Event (SAE) During the Treatment Period | An AE is defined as any untoward medical occurrence in a participant or clinical investigation participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. A serious adverse event (SAE) is defined as any untoward medical occurrence that, at any dose, results in death, is life threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity, or is a congenital anomaly/birth defect. Medical or scientific judgment should be exercised in deciding whether reporting is appropriate in other situations. Refer to the General AE/SAE module for a complete list of AEs and SAEs. | From the start of study medication until Week 11 (Visit 8)/Early Withdrawal | 
| Basophil, Eosinophil, Lymphocyte, Monocyte, Total Neutrophil, Platelet, and White Blood Cell Count Values at Day 14 of the Respective Treatment Period | Blood samples were collected for the measurement of basophils, eosinophils, lymphocytes, monocytes, total neutrophils, platelets, and white blood cell (WBC) count at Day 14 of the respective treatment period. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg. | Day 14 of the respective treatment period (up to Study Day 49) | 
| Hemoglobin and Mean Corpuscle Hemoglobin Concentration (MCHC) Values at Day 14 of the Respective Treatment Period | Blood samples were collected for the measurement of hemoglobin and MCHC at Day 14 of the respective treatment period. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg. | Day 14 of the respective treatment period (up to Study Day 49) | 
| Reticulocyte and Red Blood Cell (RBC) Values at Day 14 of the Respective Treatment Period | Blood samples were collected for the measurement of reticulocytes and RBCs at Day 14 of the respective treatment period. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg. | Day 14 of the respective treatment period (up to Study Day 49) | 
| Hematocrit Value at Day 14 of the Respective Treatment Period | Blood samples were collected for the measurement of hematocrit at Day 14 of the respective treatment period. Hematocrit is a measure of the percentage of the volume of the whole blood that is composed of red blood cells, as determined by separation of red blood cells from the plasma (usually by centrifugation). Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg. | Day 14 of the respective treatment period (up to Study Day 49) | 
| Mean Corpuscle Volume (MCV) Value at Day 14 of the Respective Treatment Period | Blood samples were collected for the measurement of MCV at Day 14 of the respective treatment period. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg. | Day 14 of the respective treatment period (up to Study Day 49) | 
| Mean Corpuscle Hemoglobin (MCH) Value at Day 14 of the Respective Treatment Period | Blood samples were collected for the measurement of MCH at Day 14 of the respective treatment period. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg. | Day 14 of the respective treatment period (up to Study Day 49) | 
| Alanine Amino Transferase (ALT), Alkaline Phosphatase (ALP), Aspartate Amino Transferase (AST), and Gamma Glutamyl Transferase (GGT) Values at Day 14 of the Respective Treatment Period | Blood samples were collected for the measurement of ALT, ALP, AST, and GGT at Day 14 of the respective treatment period. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg. | Day 14 of the respective treatment period (up to Study Day 49) | 
| Albumin and Total Protein Values at Day 14 of the Respective Treatment Period | Blood samples were collected for the measurement of albumin and total protein at Day 14 of the respective treatment period. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg. | Day 14 of the respective treatment period (up to Study Day 49) | 
| Calcium, Chloride, Carbon Dioxide (CO2) Content/Bicarbonate, Glucose, Potassium, Sodium, and Urea/Blood Urea Nitrogen (BUN) Values at Day 14 of the Respective Treatment Period | Blood samples were collected for the measurement of calcium, chloride, carbon dioxide content/bicarbonate (CO2/BI), glucose, potassium, sodium, and urea/BUN at Day 14 of the respective treatment period. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg. | Day 14 of the respective treatment period (up to Study Day 49) | 
| Total Bilirubin, Direct Bilirubin, Creatinine, and Uric Acid Values at Day 14 of the Respective Treatment Period | Blood samples were collected for the measurement of total bilirubin, direct bilirubin, creatinine, and uric acid at Day 14 of the respective treatment period. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg. | Day 14 of the respective treatment period (up to Study Day 49) | 
| Peak Expiratory Flow on Day 1, Day 8, and Day 14 of the Respective Treatment Period | Peak Expiratory Flow (PEF) is defined as the maximum airflow during a forced expiration beginning with the lungs fully inflated. PEF is calculated as the maximum of three readings taken at each timepoint for each participant. Baseline is defined as the pre-dose measurement at Day 1 for the respective period. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg (n=28). | Day 1, Day 8, and Day 14 of the respective treatment period (up to Study Day 49) | 
| Systolic Blood Pressure (SBP) and Diastolic Blood Pressure (DBP) at Day 1, Day 8, and Day 14 of the Respective Treatment Period | SBP and DBP were measured at Day 1, Day 8, and Day 14 of the respective treatment period. PD=post-dose. Baseline is defined as the pre-dose measurement at Day 1 for the respective period. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg (n=28). | Day 1, Day 8, and Day 14 of the respective treatment period (up to Study Day 49) | 
| Maximum Heart Rate at Day 1 and Day 14 of the Respective Treatment Period | Heart rate (HR) was measured at Day 1 and Day 14 of the respective treatment period. hr=hour. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg (n=28). | Day 1 and Day 14 of the respective treatment period (up to Study Day 49) | 
| Maximum QTcF at Day 1 and Day 14 of the Respective Treatment Period | The electrocardiographic (ECG) parameter QT duration corrected using Fridericia's formula (QTcF) was measured at Day 1 and Day 14 of the respective treatment period. hr=hour. For 0-8 hr parameters, treatment, period, participant Baseline, and period Baseline were fitted as fixed effects, and participant was fitted as a random effect. For 0-2 hr parameters, treatment, period, day (1 and 14), participant Baseline, period Baseline, and treatment*day interaction were fitted as fixed effects, and participant was fitted as a random effect. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg (n=28). | Day 1 and Day 14 of the respective treatment period (up to Study Day 49) | 
| Weighted Mean QTcF at Day 1 and Day 14 of the Respective Treatment Period | The electrocardiographic (ECG) parameter QT duration corrected using Fridericia's formula (QTcF) was measured at Day 1 and Day 14 of the respective treatment period. hr=hour. Actual relative times were used for the calculation except where actual times were missing. If any actual times were missing, planned relative times were used for these observations. For 0-8 hr parameters, treatment, period, participant Baseline, and period Baseline were fitted as fixed effects, and participant was fitted as a random effect. For 0-2 hr parameters, treatment, period, day (1 and 14), participant Baseline, period Baseline, and treatment*day interaction were fitted as fixed effects, and participant was fitted as a random effect. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg (n=28). | Day 1 and Day 14 of the respective treatment period (up to Study Day 49) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| AUC(0-t) and AUC(0-8) on Day 14 of the Respective Treatment Period | Area under the concentration-time (AUC) curve from time zero (pre-dose) to the last time AUC(0-t) and from time zero to 8 hours AUC(0-8) of quantifiable concentration of VI on Day 14 of the respective treatment period was measured. Samples were collected at the following times: pre-dose; 10 minutes (min) and 30 min post-dose; and 1, 2, 4, 6, and 8 hours post-dose for participants who were >=20 kilograms and pre-dose; 10 min and 30 min post-dose; and 1, 2, and 4 hours post-dose for participants who were <=20 kilograms on Day 14 of the respective treatment period. Different participants may have been analyzed for different parameters, so the overall number of participants analyzed reflects everyone in the Pharmacokinetic Population. | Day 14 of the respective treatment period (up to Study Day 49) | 
| Cmax on Day 14 of the Respective Treatment Period | Cmax is defined as the maximum observed concentration on Day 14 of the respective treatment period. Samples were collected at the following times: pre-dose; 10 minutes (min) and 30 min post-dose; and 1, 2, 4, 6, and 8 hours post-dose for participants who were >=20 kilograms and pre-dose; 10 min and 30 min post-dose; and 1, 2, and 4 hours post-dose for participants who were <=20 kilograms on Day 14 of the respective treatment period. | Day 14 of the respective treatment period (up to Study Day 49) | 
| Tmax, t1/2, and t at Day 14 of the Respective Treatment Period | tmax is defined as the time to reach the observed maximum concentration, t1/2 is defined as the time required to reduce the plasma concentration to one half its initial value, and t is defined as the time of the last observed quantifiable concentration on Day 14 of the respective treatment period. Samples were collected at the following times: pre-dose; 10 minutes (min) and 30 min post-dose; and 1, 2, 4, 6, and 8 hours post-dose for participants who were >=20 kilograms and pre-dose; 10 min and 30 min post-dose; and 1, 2, and 4 hours post-dose for participants who were <=20 kilograms on Day 14 of the respective treatment period. | Day 14 of the respective treatment period (up to Study Day 49) | 
| Blood Glucose and Potassium on Day 14 of the Respective Treatment Period | Blood glucose and potassium values were measured on Day 14 of the respective treatment period. Samples were collected at the following times: pre-dose; 10 minutes (min) and 30 min post-dose; and 1, 2, 4, 6, and 8 hours post-dose for participants who were >=20 kilograms and pre-dose; 10 min and 30 min post-dose; and 1, 2, and 4 hours post-dose for participants who were <=20 kilograms on Day 14 of the respective treatment period. . Weighted means were derived using the linear trapezoidal rule. Actual relative times were used for the calculation except where actual times were missing. If any actual times were missing, planned relative times were used for these observations. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg. Treatment and period were fitted as fixed effects and participant was fitted as a random effect. | Day 14 of the respective treatment period (up to Study Day 49) | 
| Average Oropharyngeal Cross-sectional Area on Day 1 and Day 14 of the Respective Treatment Period | During the pharyngometry assessment, participants inhaled through a wavetube, which had a mouthpiece with the same dimensions as the mouthpiece on the dry powder inhaler used for the study. This technique was used to measure the size of the throat and mouth (oropharynx) in the form of pharyngograms. Pharyngometry data were recorded for each day (Day 1 and Day 14 of the respective treatment period) using the mean of four measurements (pharyngograms), and the average oropharyngeal cross-sectional area was calculated. | Day 1 and Day 14 of the respective treatment period (up to Study Day 49) | 
| Distance of Assessment on Day 1 and Day 14 of the Respective Treatment Period | During the pharyngometry assessment, participants inhaled through a wavetube, which had a mouthpiece with the same dimensions as the mouthpiece on the dry powder inhaler used for this study. This technique was used to measure the size of the throat and mouth (oropharynx) in the form of pharyngograms. Distance of assessment is defined as the distance (length measured in centimeters [cm]) estimated to be from the lips to the larynx. Pharyngometry data were recorded for each day (Days 1 and 14 of the respective treatment period) using the mean of four measurements (pharyngograms), and the average oropharyngeal cross-sectional area was calculated. | Day 1 and Day 14 of the respective treatment period (up to Study Day 49) | 
| Oropharyngeal Volume on Day 1 and Day 14 of the Respective Treatment Period | During the pharyngometry assessment, participants inhaled through a wavetube, which had a mouthpiece with the same dimensions as the mouthpiece on the dry powder inhaler used for this study. This technique was used to measure the size of the throat and mouth (oropharynx) in the form of pharyngograms. Oropharyngeal volume is defined as the volume (centimeters cubed [cm^3]) of the mouth and throat estimated to be from the lips to the larynx. Pharyngometry data were recorded for each day (Days 1 and 14 of the respective treatment period) using the mean of four measurements (pharyngograms), and the average oropharyngeal cross-sectional area was calculated. | Day 1 and Day 14 of the respective treatment period (up to Study Day 49) | 
| Average Flow Rate and Peak Inspiratory Flow Rate (PIFR) on Day 1 and Day 14 of the Respective Treatment Period | During the inhalation profile assessment, participants inhaled through a mouthpiece from a device with a similar resistance to the dry powder inhaler used for this study. Average flow rate is defined as the average inspiratory flow rate (Liters [L]/min) across the inhalation profile when inhaling across the resistance of the inhaler. PIFR is defined as the Peak Inspiratory Flow Rate (L/min) of the inhalation profile when inhaling across the resistance of the inhaler.The pressure drop during the inhalation was measured, and the inhalation profiles (pressure drop versus time profile) of the participants were obtained. The mean of the two inhalation profile measurements was used for each day (Days 1 and 14 of the respective treatment period), and the average flow rate and PIFR were determined. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg. | Day 1 and Day 14 of the respective treatment period (up to Study Day 49) | 
| Inhalation Time on Day 1 and Day 14 of the Respective Treatment Period | During the inhalation profile assessment, participants inhaled through a mouthpiece from a device with a similar resistance to the dry powder inhaler used for this study. Inhalation time is defined as the duration of the inhalation(s) when inhaling across the resistance of the inhaler. The pressure drop during the inhalation was measured, and the inhalation profiles (pressure drop versus time profile) of the participants were obtained. The mean of the two inhalation profile measurements was used for each day (Days 1 and 14 of the respective treatment period), and the inhalation time was determined. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg. | Day 1 and Day 14 of the respective treatment period (up to Study Day 49) | 
| Inhaled Volume on Day 1 and Day 14 of the Respective Treatment Period | During the inhalation profile assessment, participants inhaled through a mouthpiece from a device with a similar resistance to the dry powder inhaler used for this study. Inhaled volume is defined as the volume of air (Liters) inhaled during the inhalation across the resistance of the inhaler. The pressure drop during the inhalation was measured, and the inhalation profiles (pressure drop versus time profile) of the participants were obtained. The mean of the two inhalation profile measurements was used for each day (Days 1 and 14 of the respective treatment period), and the inhalaled volume was determined. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg. | Day 1 and Day 14 of the respective treatment period (up to Study Day 49) | 
| Peak Pressure Drop on Day 1 and Day 14 of the Respective Treatment Period | During the inhalation profile assessment, participants inhaled through a mouthpiece from a device with a similar resistance to the dry powder inhaler used for this study. Peak pressure drop is defined as the maximum pressure drop (kilopascal [kPa]) achieved during inhalation across the resistance of the inhaler. The pressure drop during the inhalation was measured, and the inhalation profiles (pressure drop versus time profile) of the participants were obtained. The mean of the two inhalation profile measurements was calculated for each day (Days 1 and 14 of the respective treatment period), and used for subsequent modeling and prediction of dose emission attributes. Subject 2308 received VI 25 µg in both treatment periods, and contributed twice to the summary of VI 25 µg. | Day 1 and Day 14 of the respective treatment period (up to Study Day 49) | 
| Total Emitted Dose (TED) on Day 1 and Day 14 of the Respective Treatment Period | The total emitted dose (TED) is defined as the mass (micrograms) of the nominal dose that passes beyond the throat. The recorded inhalation profiles of the participants and the mouth-throat (oropharyngeal) models of the sizes that approximated to pharyngometry measurements of the participants were used in conjunction with the electronic Lung (eLung) for in vitro assessment. The eLung is a breathing simulator that replicates the selected inhalation profile with an active inhaler placed at the lips end of the selected ororpharyngeal model. After the dose is emitted from the inhaler, the analysis and assay of throat deposition and material passing beyond the throat was used to derive the nominal, minimum, and maximum predicted total emitted dose. | Day 1 and Day 14 of the respective treatment period (up to Study Day 49) | 
| Ex-throat Dose (ETD) and ETD <2 Microns on Day 1 and Day 14 of the Respective Treatment Period | The ex-throat dose (ETD) and the nominal ETD is the mass (micrograms) of active investigational material that passes beyond the throat, nominal being the mean.The recorded inhalation profiles of the participants and the mouth-throat (oropharyngeal) models of the sizes that approximated to pharyngometry measurements of the participants were used in conjunction with the electronic Lung (eLung) for in vitro assessment. The eLung is a breathing simulator that replicates the selected inhalation profile with an active inhaler placed at the lips end of the selected ororpharyngeal model. After the dose is emitted from the inhaler, the analysis and assay of throat deposition and material passing beyond the throat was used to derive the nominal, minimum, and maximum predicted ETD and ETD <2 microns. | Day 1 and Day 14 of the respective treatment period (up to Study Day 49) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Tolerability, Safety, Pharmacokinetics, GW642444, Asthma