Peak expiratory flow as an endpoint for clinical trials in asthma: a comparison with FEV1.

BACKGROUND: The primary lung function endpoint in clinical trials in adolescent and adult patients with asthma is usually forced expiratory volume in one second (FEV1). The objective of our analysis was to assess whether peak expiratory flow (PEF) is a suitable alternative primary lung function endpoint. METHODS: For this assessment, we calculated post hoc the correlation between pre-dose FEV1 and pre-dose PEF measured under supervision in the clinic and, for both lung function parameters, the correlations between supervised clinic and unsupervised home measurements, using the results from the 8 Phase III parallel-group trials of the global clinical development programme with tiotropium Respimat® in patients with asthma aged 12 to 75 years. RESULTS: Across all 8 trials included in this analysis, changes in lung function from baseline correlated well between pre-dose FEV1 and pre-dose PEF when both were measured under supervision in the clinic. Correlation between supervised in-clinic and unsupervised home measurements was stronger for pre-dose PEF than for pre-dose FEV1. CONCLUSIONS: Pre-dose PEF measured at home could be an alternative primary lung function endpoint for trials in adolescent and adult patients with asthma. Using home-measured PEF could facilitate trial conduct and improve the convenience for patients by relocating scheduled assessments from the clinic to the patient's home. TRIAL REGISTRATION: Adolescents aged 12 to 17 years: RubaTinA-asthma® ( NCT01257230 ), PensieTinA-asthma® ( NCT01277523 ). Adults aged 18 to 75 years: GraziaTinA-asthma® ( NCT01316380 ), MezzoTinA-asthma® ( NCT01172808 / NCT01172821 ), CadenTinA-asthma® ( NCT01340209 ), PrimoTinA-asthma® ( NCT00772538 / NCT00776984 ). All from Clinicaltrials.gov ( https://clinicaltrials.gov/ ).

Safety of tiotropium Respimat® in black or African-American patients with symptomatic asthma.

BACKGROUND: Black patients with asthma have a higher disease burden and greater morbidity compared with other racial/ethnic groups. Tiotropium Respimat®, as add-on to at least inhaled corticosteroids (ICS), improves lung function and asthma control and reduces asthma exacerbation risk in patients, with a safety profile comparable with placebo. This study aimed to assess the safety of tiotropium Respimat®, compared with placebo, in black or African-American patients. METHODS: Data were pooled from 12 randomized, placebo-controlled, parallel-group, Phase II or III trials from the global Boehringer Ingelheim program with once-daily tiotropium Respimat® (5 µg or 2.5 µg). Trial participants had symptomatic persistent asthma with a broad range of severities and were aged 1-75 years. The safety results of black or African-American patients were compared with the overall trial population. RESULTS: Of the 5165 patients treated with tiotropium or placebo, 3.2% were black or African American. For both doses of tiotropium, the proportion of patients reporting adverse events (AEs) was approximately 10% lower compared with placebo and was generally comparable with the proportion of patients reporting AEs in all groups of the overall population. The number of investigator-assessed drug-related AEs, AEs leading to trial drug discontinuation or serious AEs reported by patients was low and comparable between treatment groups and with the overall population. CONCLUSION: Tiotropium Respimat® appears to be a generally safe add-on bronchodilator treatment option to ICS with or without other controllers in pediatric and adult black or African-American patients with asthma. CLINICAL TRIAL IDENTIFIERS: NCT01634113, NCT01634139, NCT01634152, NCT01257230, NCT01277523, NCT01316380, NCT00350207, NCT01172808, NCT01172821, NCT01340209, NCT00772538, NCT00776984.