Real-world Effectiveness and Cost-effectiveness of Qvar Versus FP, a US Study
Condition: Asthma
MeSH terms: Asthma
Study type: Observational

Summary: 
      This study will compare the absolute and relative effectiveness and cost-effectiveness of
      asthma management in patients in the USA on inhaled corticosteroid (ICS) maintenance therapy
      as HFA-BDP (Qvar®) pressurised metered dose inhaler (pMDI) compared with fluticasone
      propionate (FP) pMDI. .
    

Detailed description: 
      Current asthma guidelines 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 only a small percentage of the real-world 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 to carry
      out real-world observational studies to inform existing guidelines on the effectiveness of
      available treatments as used in every-day clinical practice in the heterogeneous asthma
      population.

      Asthma management guidelines recommend long-term, daily anti-inflammatory controller therapy
      to attenuate the chronic airway inflammation of persistent asthma. The choice of inhaled
      corticosteroid can be guided by practical considerations (e.g., cost factors) as RCTs have so
      far failed to identify consistent, significant differences in outcomes among the available
      inhaled corticosteroids, and data from observational studies are lacking.

      FP and HFA-BDP are the two main ICS therapies prescribed in the US for the management of
      asthma. FP is approximately twice as potent and efficacious, on a microgram basis, as BDP. In
      clinical trials, however, the extra-fine hydrofluoroalkane (HFA) formulation of BDP has
      demonstrated potency similar to that of FP. This is felt to be because HFA-BDP shows higher
      and more even lung deposition than FP, with HFA-BDP, unlike FP, having distribution to both
      large and small airways.

      Owing to similarity of effectiveness of extra-fine HFA-BDP and FP suggested by clinical trial
      data, and the even lung distribution afforded by the smaller HFA aerosol particles, we
      hypothesises that extra-fine HFA-BDP may be at least as effective as FP in real-world
      clinical practice. This hypothesis was supported by a retrospective database study of HFA-BDP
      versus FP using the UK's General Practice Research Database (GPRD). The study found
      significantly lower odds for achieving the composite proxy measure for asthma control with FP
      in both patients initiating ICS therapy (0.77, 95%CI 0.61-0.98) and stepping-up ICS therapy
      (0.82, 95%CI 0.44-1.52) relative to HFA-BDP. The analysis also revealed that FP was
      prescribed at significantly higher doses than extra-fine HFA-BDP yet had lower associated
      odds of achieving asthma control.

      In addition to significant health benefits, delivering effective asthma control is critical
      to reducing the substantial economic burden of asthma, with research indicating annual costs
      are disproportionately attributable to patients with poorly controlled disease. Recent
      estimates place the annual figure at 56 billion dollars ($) in the US alone, consisting of
      direct costs and productivity losses.It is therefore of particular importance to consider
      outcomes achieved in relation to costs incurred when assessing overall benefit of asthma
      therapies, with a cost-effectiveness analysis of HFA BDP and FP planned as part of the
      current study.

      The aim of this study is to compare the absolute and relative effectiveness and
      cost-effectiveness of asthma management in patients in the US on inhaled corticosteroid (ICS)
      maintenance therapy as extra-fine HFA-BDP (Qvar®) pressurised metered dose inhaler (pMDI)
      compared with fluticasone propionate (FP) pMDI to further examine the findings of the UK
      study, and to identify similarities or differences in effectiveness and cost-effectiveness
      outcomes and prescribing practice between the two countries.
    

Intervention name(s): extra-fine hydrofluoroalkane beclometasone dipropionate; Fluticasone propionate
Intervention type(s): Drug; Drug
Other intervention name(s): Qvar®
Intervention MeSH terms: Fluticasone; Xhance; Beclomethasone
Observational model: Cohort
Time perspective: Retrospective
Sampling method: Non-Probability Sample
Study population: 
        Asthma patients who either:

        (i) Initiate ICS therapy as one of:

          -  HFA-BDP pMDI

          -  FP pMDI

        OR

        (ii) Step up ICS therapy as one of:

          -  HFA-BDP pMDI

          -  FP pMDI
      
Keywords: Real-world; observational; Fluticasone propionate; Metred dose inhaler; Extra-fine hydrofluoroalkane; Asthma management; Inhaled corticosteroids; Beclomethasone dipropionate; USA