Managing a variable disease

New approaches to managing asthma: a US perspective

Despite remarkable advances in diagnosis and long-term management, asthma remains a serious public health concern. Newly updated expert guidelines emphasize the intra- and inter-individual variability of asthma and highlight the importance of periodic assessment of asthma control. These guidelines update recommendations for step-wise asthma treatment, address the burgeoning field of asthma diagnostics, and stress the importance of a patient and health care professional partnership, including written action plans and self monitoring. The field of asthma therapeutics is expanding rapidly, with promising new treatment options available or in development that may address some of the existing barriers to successful asthma management. These approaches simplify treatment, use combinations of agents in one delivery device that have complementary actions, or target specific pathways involved in asthma patho-physiology. Considerable activity is taking place in asthma pharmacogenetics. This review provides an overview of these new approaches to managing asthma, including their present status and future potential.

Randomized comparison of ciclesonide 160 and 640 microg/day in severe asthma

OBJECTIVE

Demonstrating clinical benefit of higher doses of inhaled corticosteroids in asthma is frequently problematic owing to their relatively flat dose-response curve in this condition. In this study we compared the efficacy and safety of a fourfold difference in the dose of ciclesonide-ciclesonide 320 microg twice daily (CIC640) versus ciclesonide 160 microg once daily (CIC160)-in patients with severe persistent asthma.

METHODS

Patients with bronchial asthma (6 months) were included in this randomized, double-blind study. After receiving fluticasone propionate 250 microg twice daily during run-in, patients were randomized to CIC160 (n=339) or CIC640 (n=341) for 12 weeks. Primary endpoints were time to first asthma exacerbation and forced expiratory volume in 1s (FEV(1)). Secondary endpoints included other lung function variables, asthma symptom scores and rescue medication use (RMU).

RESULTS

Asthma exacerbations occurred in 12.7% of patients receiving CIC160 and 6.7% receiving CIC640. CIC640 was superior for time to first exacerbation (p=0.0050, one-sided). FEV(1) increased significantly with CIC160 and CIC640 (least squares mean+/-SE of mean: 269+/-31 and 332+/-31 mL, respectively; p<0.0001), with no significant difference between groups. Change in % predicted FEV(1) and morning peak expiratory flow (PEF) were significantly higher with CIC640 (p<0.05). Asthma symptom score sums and RMU decreased in both groups; CIC640 was statistically superior (p=0.0108 and 0.0005, respectively). No unexpected adverse events were reported in either group and the majority of the events reported were mild or moderate in intensity. No significant changes in serum cortisol were observed from the baseline to the study end. Small decreases in creatinine-adjusted 24h urine cortisol levels from baseline were seen in both the treatment groups, which, due to the large patient numbers, were statistically significant (p<0.05); however, no dose-response effect was seen and the difference between groups was not significant (p=0.7892).

CONCLUSION

CIC640 was superior to CIC160 for time to first exacerbation, % predicted FEV1, morning PEF, asthma symptom score sum and RMU in patients with severe asthma; both doses had similar tolerability profiles and no significant changes in serum cortisol were seen in either treatment group.

Assessment of asthma control and its impact on optimal treatment strategy

Achieving and maintaining optimal asthma control is a major asthma management goal advocated by the Global Initiative for Asthma (GINA). Recent evidence suggests that while asthma control is clearly achievable in most asthmatics, not all asthmatics attain optimal asthma control. The difficulty is compounded further because patients, physicians and regulatory bodies have different perceptions of what is meant by asthma control. The challenge therefore remains as to how best to assess asthma control and define management strategies to ensure that this control is achieved and maintained. Despite the availability of several patient-based tools for assessing asthma control, these are mostly employed in a research setting or in selected specialist clinics. A symptom-based treatment approach also may have its limitations because patients can be poor judges of disease symptoms and severity and under-estimation may lead to inadequate treatment of airway inflammation and airway hyperresponsiveness (AHR) when treatment is administered as on-demand reliever therapy, since the effect of treatment on these underlying features occurs over a longer time course. The clinical benefits of sustained maintenance treatment for at least 3 months has been documented in recent studies of salmeterol/fluticasone propionate combination, which have demonstrated correlations between reduction in airway inflammation/AHR and reduction in exacerbation rates. In view of the putative limitations of a purely symptom-based asthma management plan, we suggest that treatment should be focussed on management of all aspects of the disease rather than management of symptoms alone, with a practical approach being treatment for a minimum of 3 months with an optimal dose to ensure maximal effects are seen on asthma control, airway inflammation, lung function, and remodelling.

Budesonide/formoterol: a review of its use in asthma

Budesonide and formoterol have been combined in a single dry powder device, Symbicort Turbuhaler (budesonide/formoterol 160/9-640/18 microg/day), in an effort to simplify asthma management. The efficacy of budesonide/formoterol as maintenance therapy in patients with asthma has been examined in several randomised studies.Twice-daily budesonide/formoterol was significantly more effective than an equivalent or higher daily dose of budesonide alone or high-dose fluticasone propionate alone at improving peak expiratory flow (PEF) in adults with predominantly moderate persistent asthma. Symptom control and the risk of mild exacerbations were significantly improved versus budesonide alone. Moreover, budesonide/formoterol appeared to be as effective as concurrent therapy with equivalent dosages of budesonide and formoterol administered via separate inhalers in adults with moderate persistent asthma. Budesonide/formoterol administered once daily was as effective as twice-daily administration (equivalent daily doses) and more effective than once-daily budesonide in adults with moderate persistent asthma. Twice-daily budesonide/formoterol significantly improved PEF compared with budesonide in paediatric patients with asthma. Adjustable maintenance dosing with budesonide/formoterol was associated with significantly less study drug use than fixed dosing with budesonide/formoterol in adults with predominantly mild or moderate persistent asthma. In two of three studies (all longer than 4 months' duration), the risk of exacerbations was significantly lower with adjustable than with fixed dosing, but no difference was detected in four short-term studies. Symptom severity was maintained or improved in most patients receiving either treatment regimen. In adults with moderate-to-severe persistent asthma, adjustable maintenance dosing with budesonide/formoterol reduced the rate of exacerbations and reliever medication use compared with fixed dosing with salmeterol/fluticasone propionate. Budesonide/formoterol was well tolerated in both fixed and adjustable dosing regimens. In conclusion, in patients with persistent asthma symptoms despite treatment with inhaled corticosteroids, budesonide/formoterol administered via a single dry powder Turbuhaler device is an effective, well tolerated, convenient treatment option, which may have the potential for improved compliance. It appears to be as effective as treatment with budesonide and formoterol administered via separate inhalers and is more effective than budesonide monotherapy in improving PEF, controlling symptoms and preventing mild exacerbations. Adjustable maintenance dosing with budesonide/formoterol is associated with a lower overall dosage and appears to maintain control as effectively as fixed dosing.

The long and short of beta2-agonists

For patients whose asthma is not adequately controlled with inhaled corticosteroid (ICS) therapy alone, increasing the dose of ICS or the addition of a long-acting beta(2)-agonist is recommended. Greater improvements in lung function are achieved with the addition of a long-acting beta(2)-agonist to ICS therapy, rather than doubling the dose of ICS. Formoterol and salmeterol have a similarly long duration of effect (up to 12 h). However, as a result of their different chemical structures, there are marked pharmacological differences in the mechanism of action which affect their speeds of onset. These differences amount to a more rapid onset of effect for formoterol compared with salmeterol. Long-acting beta(2)-agonists appear to be well tolerated at elevated doses. These two features (tolerability at high doses and rapid onset of effect) support the use of formoterol as a reliever medication in addition to use in maintenance therapy. The long-acting beta(2)-agonists can be considered as beneficial additions to ICS therapy for the management of moderate-to-severe asthma.

Living with a variable disease

Asthma is a variable disease which, when not fully controlled, may leave the patient with a sense of bewilderment, fear, anger and a loss of many 'normal' activities of daily living. The reasons for these fears range from the concern of having an asthma attack to concerns about taking medications, perhaps especially steroids. Complex treatment regimens and a lack of understanding by the patient of their asthma may lead to denial and a reduction in adherence to medication resulting in poor treatment outcomes. Patients' lack of understanding may originate from poor communication between patient and physician. Improved communication and ensuring that all of the patient's questions are answered, as well as simpler treatment regimens may improve asthma control. Detailed, written personal asthma action plans should act as a foundation for building good relationships between doctor and patient and enhance adherence. Simplifying treatment regimens, such as having an inhaled corticosteroid and a long-acting, beta(2)-agonist in a single inhaler, used in conjunction with these personal asthma action plans, should provide a therapy that enables patients to be in control of their asthma without having to live in fear of their illness.