Primary Outcome Measures:
- The primary endpoint is the bronchodilator effect expressed as the mean area under the curve (AUC) of FEV1 (% change from Same-Day Baseline FEV1) versus time. [ Time Frame: Concurent with each visit ] [ Designated as safety issue: No ]
Secondary Outcome Measures:
- The comparative analysis of AUC of FEV1 (% change from the Same-Day Baseline) versus time, for bronchodilator effect (between Albuterol-HFA and Proventil-HFA). [ Time Frame: End of Study ] [ Designated as safety issue: No ]
- AUC of FEV1-time curve (changes of actual volumes from the Same-Day Baseline). [ Time Frame: End of Study ] [ Designated as safety issue: No ]
- Time to onset of bronchodilator effect, determined by linear interpolation as the time point where FEV1 first reaches 12% over Same-Day Baseline. [ Time Frame: End of Study ] [ Designated as safety issue: No ]
- The peak bronchodilator response, defined as the maximum FEV1 (% change from Same-Day Baseline) post-dose. [ Time Frame: end of study ] [ Designated as safety issue: No ]
- The time to peak FEV1 effect, measured as the time point of peak response, as defined (4) above. [ Time Frame: End of Study ] [ Designated as safety issue: No ]
- Duration of bronchodilator effect, defined as the total length of time when FEV1 is maintained 12% above the respective Same-Day Baseline values (time points calculated with linear interpolation). [ Time Frame: Concurrent with each visit ] [ Designated as safety issue: No ]
- Percentage of positive responders including those whose FEV1 exceed the Same-Day Baseline by 12% within 30 minutes post-dose (quick responders), and during the entire 6 hr post-dose (overall responders). [ Time Frame: Concurrent with visit ] [ Designated as safety issue: No ]
- Number of inhalations of the rescue inhalers taken. [ Time Frame: Concurrent with each visit ] [ Designated as safety issue: No ]
- Global assessment of Overall Asthma Control Scores by investigators. [ Time Frame: End of Study ] [ Designated as safety issue: No ]
- Total daytime asthma symptom scores. [ Time Frame: End of Study ] [ Designated as safety issue: No ]
- Nighttime sleep disturbance scores. [ Time Frame: End of Study ] [ Designated as safety issue: No ]
- Morning pre-dose Peak Expiratory Flow Rate (PEF). [ Time Frame: Concurrent with each visit ] [ Designated as safety issue: No ]
- The clinical performances of the Albuterol-HFA MDI at the representative first, middle and last one third of the usable life stage, are compared with each other, and are also compared to those of the active control, Proventil-HFA. [ Time Frame: End of Study ] [ Designated as safety issue: No ]
- The in vitro performance of the Albuterol-HFA MDI will be evaluated. [ Time Frame: Concurrent with each visit ] [ Designated as safety issue: No ]
- Vital signs (SBP/DBP, and heart rate) will be monitored at Clinical Visit 1, 3 and 5, at baseline (within 30 minutes prior to dosing), and 90+/-15 min, and 360+/-30 min, post-dose. [ Time Frame: concurrent with study visits as noted ] [ Designated as safety issue: Yes ]
- A 12-lead ECG (for HR, QT and QTc intervals) will be recorded at Screening Visit, and at baseline (within 30 min) pre-dose and at 90+/-15 min post-dose (predicted time of peak effect). [ Time Frame: Clinical Visits 1 and 5 ] [ Designated as safety issue: Yes ]
- Data for CBC, blood chemistry panel (8-hr fasted), and urinalysis. [ Time Frame: Screening and end-of-study ] [ Designated as safety issue: Yes ]
- Study compliance and diaries will be reviewed [ Time Frame: at all cliniical visits ] [ Designated as safety issue: Yes ]
- Concomitant medications will be reviewed and recorded [ Time Frame: each study visit ] [ Designated as safety issue: Yes ]
- Adverse events/side effects whether observed by investigators or reported by subjects, will be documented, evaluated, followed up, and treated if deemed necessary. [ Time Frame: concurrent with each study visit ] [ Designated as safety issue: Yes ]
This is a randomized, parallel, multicenter, 12-week study in adolescent and adult patients with mild-to-moderate asthma, to evaluate the efficacy and safety of Armstrong's Albuterol-HFA MDI, in comparison to a Placebo Control and an Active Control of Proventil-HFA. While Albuterol-HFA (Treatment T) and Placebo (Treatment P) will be double-blinded to both the subjects and investigational staff, the active comparator drug, Proventil-HFA (Treatment R), can only be evaluator-blinded, due to: (1) its physical appearance differing from that of the T and P devices; and (2) unavailability of a Proventil-HFA placebo which would otherwise be used for a double-dummy design. All study medications will have the canisters and all product-identifying text or graphics (e.g., molded text on actuator) masked so that the treatments cannot be identified. No subject in any study arm will be given any information that could reveal the nature of the treatment given. All study subjects will be instructed not to reveal or discuss the study medications to the study staff or other subjects. The designated study evaluator(s), who conduct the clinical visits and safety and efficacy evaluations and perform the data recording and transcription, will be blinded to the study medications.
All subjects will be screened for enrollment, and will be randomized into the following three treatment groups in a double-blinded (for Treatments T and P) or evaluator-blinded (for Treatment R) manner:
Treatment T (Albuterol-HFA, N=200): 216 mcg albuterol sulfate (equivalent to 180 mcg albuterol base), QID; Treatment R (Proventil-HFA, N=50): 216 mcg albuterol sulfate (equivalent to 180 mcg albuterol base), QID; Treatment P (Placebo-HFA, N=50): two actuations of placebo, QID.
Randomization is achieved with blocks of six (6), with four (4) patients receiving Albuterol-HFA for every one (1) patient receiving Proventil-HFA and every one (1) receiving the Placebo-HFA. At each Clinical Visit that takes place every 3 weeks, the double-blinded (T, P) or evaluator-blinded (R) study drugs will be distributed in resealable masking pouches to the subjects of each arm.
An additional aim of the study is to evaluate the effect of weekly cleaning on the Albuterol-HFA MDI device clinical performance throughout the four, 3-week life-of-device treatment cycles, in conformance with the FDA's specific requirements.
Arms:
All subjects will be screened for enrollment, and will be randomized into the following three treatment groups in a double-blinded (for Treatments T and P) or evaluator-blinded (for Treatment R) manner:
Treatment T (Albuterol-HFA, N=200): 216 mcg albuterol sulfate (equivalent to 180 mcg albuterol base), QID; Treatment R (Proventil-HFA, N=50): 216 mcg albuterol sulfate (equivalent to 180 mcg albuterol base), QID; Treatment P (Placebo-HFA, N=50): two actuations of placebo, QID.