RT Journal Article
SR Electronic
T1 Examination of variations in responder rates in COPD clinical trial outcomes
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP P4152
VO 42
IS Suppl 57
A1 Paul Jones
A1 Marc Decramer
A1 Jadwiga A. Wedzicha
A1 Donald Banerji
YR 2013
UL http://erj.ersjournals.com/content/42/Suppl_57/P4152.abstract
AB BackgroundThe MCID (minimum clinically important difference) is used to identify responders to treatment in clinical trials, enabling a comparison of responder rates between treatment arms. Relatively little is published about responder rates and their variation between trials.MethodsData from three clinical trials with once-daily QVA149 (glycopyrronium (GLY) + indacaterol (IND)), GLY, IND, tiotropium (TIO) and placebo (PB) was compared to examine the size of the variation in responder rates.ResultsHigh responder rates were seen with PB, ranging from 44.2% to 57.5% (table). Very high TDI and SGRQ responder rates were observed with QVA149 but that study also had the highest PB responder rate. Using TIO as an active comparator, it can be seen that the range of response to treatment was wide (47.3-59.4). Spearman’s rho = 0.66 between TIO and PB suggesting an association between their response rates, but the difference between TIO-PB responder rates varied in the range -0.02 to 10.7 between outcomes and trials.View this table:Percent respondersConclusionPlacebo responder rates vary across studies. Studies in which more than half of the patients have a clinically significant response to placebo may be particularly problematic to interpret, especially when exploring differences between treatments.