Current asthma guidelines in the UK are underpinned by evidence derived from randomised controlled trials (RCTs). Although RCT data are considered the gold standard, patients recruited to asthma RCTs are estimated to represent less than 10% of the UK's asthma population. The poor representation of the asthma population is due to a number of factors, such as tightly-controlled inclusion criteria for RCTs. There is, therefore, a need for more representative RCTs and real-life observational studies to inform existing guidelines and help optimise asthma outcomes.
Short randomised trials have shown that Qvar is at least as effective as FP pMDI and as BDP pMDI at half the prescribed dose in patients with asthma. There is also evidence to suggest that, in adults, HFA formulation as used by Qvar (featuring BDP in solution rather than suspension) may achieve 10-fold higher deposition compared with CFC-BDP.4 Furthermore, deposition in the peripheral regions is higher compared with CFC-BDP and the fine-particle formulation also offers greater tolerance of poor co-ordination of breathing and inhaler actuation, resulting in lower oro-pharyngeal deposition compared with CFC-BDP.
Evidence of the efficacy of ICS monotherapy in COPD remains mixed at this time. While Qvar and ICS monotherapy use in the treatment of COPD is currently off-label, it occurs in clinical practice in two common scenarios:
1. before a diagnosis of COPD is made
2. unlicensed use as monotherapy, or in combination with long-acting bronchodilators
The study hypothesis, therefore, is that Qvar treatment in COPD may be associated with improved disease management and control (as assessed by effectiveness, cost-effectiveness and direct healthcare costs of managing COPD) compared with other commonly used ICS therapies, namely BPD and FP, by virtue of its improved deposition throughout the lungs and the small airways.