Complexity of design in early phase respiratory clinical trials; evaluating impact of primary endpoints and sponsor size.

Asthma and COPD represent most of the clinical trials in the respiratory area. The Primary Endpoint (PE) defines how trials are conducted. We hypothesised that small and mid-sized pharmaceutical companies may be innovative in the selection of their trial endpoints, to be time- and cost-effective. To test this, a record of industry-sponsored phase II trials in asthma, COPD and Asthma/COPD over 11 years was obtained. The type of PE and the influence these had on length, number of subjects and investigational trial sites were evaluated for the different disease categories. Differences in the type of PE used by large versus small/mid-sized companies were found for both asthma and COPD trials (p = 0.011 and 0.025), with sponsorship influencing the conduction of these. In asthma, studies sponsored by large companies were significantly longer than those from smaller companies (p = 0.0001). Additionally, large companies intended to recruit more subjects (asthma: p = 0.0048, COPD: p ≤ 0.0001) and use more investigational sites (asthma: p = 1 × 10, COPD: p = 1 × 10) than those from small and mid-size companies. A sub-analysis of the time and subject requirements associated with each type of PE did not provide an explanation for the differences observed. In conclusion, this exploratory analysis indicates differences in study size, duration and type of PE used by small/mid-sized and large companies. For some types of endpoints, differences in length and study size were found. However, it wasn't possible to attribute these differences between sponsors solely to the choice of PE, pointing out to the complexity of running clinical trials.