Mepolizumab in a population with severe eosinophilic asthma and corticosteroid dependence: results from a French early access programme

Assessing the cost-effectiveness of mepolizumab as add-on therapy to standard of care for severe eosinophilic asthma in Singapore

OBJECTIVE

To evaluate the cost-effectiveness of mepolizumab added to standard of care (SOC) compared with SOC alone among patients with severe uncontrolled eosinophilic asthma in the Singapore setting.

METHODS

A Markov model with three health states (asthma on mepolizumab and SOC, asthma on SOC alone, and death) was developed from a healthcare system perspective over a lifetime horizon. During each 4-week cycle, patients in the non-death health states could experience asthma exacerbations requiring oral corticosteroid burst, emergency department visit, or hospitalization. Asthma-related mortality following an exacerbation or all-cause mortality could also occur at each cycle. The model was populated using local costs while utilities were derived from international literature. Transition probabilities were obtained from a mixture of Singapore-specific and internationally published data.

RESULTS

The base-case analysis comparing mepolizumab plus SOC with SOC alone resulted in an incremental cost-effectiveness ratio (ICER) of SGD335 486 (USD238 195) per quality-adjusted life-year (QALY) gained. Sensitivity analysis demonstrated that the ICER was most sensitive to the price of mepolizumab, followed by the proportion of exacerbations which required hospital intensive care. Despite restricting mepolizumab use to patients with a higher baseline exacerbation rate (3 in the past year) in a scenario analysis, the ICER remained high at SGD238 876 (USD 169 602) per QALY gained.

CONCLUSION

At its current price, mepolizumab is not considered a cost-effective use of healthcare resources in Singapore. Substantial price reductions for mepolizumab are required to improve its cost-effectiveness to an acceptable range. These results will be useful to inform national funding decisions.

Long-Term Therapy Response to Anti-IL-5 Biologics in Severe Asthma-A Real-Life Evaluation

BACKGROUND

Patients with severe eosinophilic asthma show different responses to various anti-IL-5 biologics, ranging from super response to nonresponse. Residual disease manifestations observed in partial responders may prompt physicians to switch between biologics. More data on response, switches, and residual disease manifestations are needed to improve personalized treatment.

OBJECTIVE

To assess (1) prevalences and predictors of super, partial, and nonresponders to long-term anti-IL-5 treatment, (2) frequency and reasons for switches between anti-IL-5 biologics, and (3) nature of residual disease manifestations.

METHODS

In this 2-year follow-up study, patients with severe asthma were included who initiated an anti-IL-5 biologic (mepolizumab, reslizumab, benralizumab) (n = 114). Patient characteristics (clinical, functional, inflammatory) and comorbidities were collected at baseline and 2-year follow-up. "Super responders" showed no residual disease manifestations at 2-year follow-up, "partial responders" experienced residual disease manifestations, and "nonresponders" discontinued anti-IL-5 treatment after less than 2 years because of clinical worsening.

RESULTS

After 2-year anti-IL-5 treatment, 14% of patients were super responders, 69% partial responders, and 11% nonresponders. Super response was predicted by shorter asthma duration and higher FEV₁, and tended to be associated with adult-onset asthma, absence of nasal polyps, and lower body mass index. Switches between anti-IL-5 biologics occurred frequently (41%). After 2-year treatment, most common residual disease manifestations included impaired lung function (59%), uncontrolled sinonasal disease (58%), and uncontrolled asthma symptoms (48%).

CONCLUSIONS

After 2 years of anti-IL-5 treatment, a favorable response was found in 83% of patients with severe asthma, including a super response in 14%. Most partial responders show impaired lung function or uncontrolled sinonasal disease, causing physicians to switch between biologics.

Suboptimal treatment response to anti-IL-5 monoclonal antibodies in severe eosinophilic asthmatics with airway autoimmune phenomena

BACKGROUND

In clinical trials, the two anti-interleukin (IL)-5 monoclonal antibodies (mAbs: mepolizumab and reslizumab) approved to treat severe eosinophilic asthma reduce exacerbations by ∼50-60%.

OBJECTIVE

To observe response to anti-IL-5 mAbs in a real-life clinical setting, and to evaluate predictors of suboptimal response.

METHODS

In four Canadian academic centres, predefined clinical end-points in 250 carefully characterised moderate-to-severe asthmatic patients were collected prospectively to assess response to the two anti-IL-5 mAbs. Suboptimal response was determined based on failure to reduce maintenance corticosteroid (MCS) or asthma symptoms scores (Asthma Control Questionnaire (ACQ)) or exacerbations, in addition to persistence of sputum/blood eosinophils. Worsening in suboptimal responders was assessed based on reduced lung function by 25% or increase in MCS/ACQ. A representative subset of 39 patients was evaluated for inflammatory mediators, autoantibodies and complement activation in sputum (by ELISA) and for immune-complex deposition by immunostaining formalin-fixed paraffin-embedded sputum plugs.

RESULTS

Suboptimal responses were observed in 42.8% (107 out of 250) patients treated with either mepolizumab or reslizumab. Daily prednisone requirement, sinus disease and late-onset asthma diagnoses were the strongest predictors of suboptimal response. Asthma worsened in 13.6% (34 out of 250) of these patients. The majority (79%) of them were prednisone-dependent. Presence of sputum anti-eosinophil peroxidase immunoglobulin (Ig)G was a predictor of suboptimal response to an anti-IL-5 mAb. An increase in sputum C3c (marker of complement activation) and deposition of C1q-bound/IL-5-bound IgG were observed in the sputa of those patients who worsened on therapy, suggesting an underlying autoimmune-mediated pathology.

CONCLUSION

A significant number of patients who meet currently approved indications for anti-IL5 mAbs show suboptimal response to them in real-life clinical practice, particularly if they are on high doses of prednisone. Monitoring blood eosinophil count is not helpful to identify these patients. The concern of worsening of symptoms associated with immune-complex mediated complement activation in a small proportion of these patients highlights the relevance of recognising airway autoimmune phenomena and this requires further evaluation.

Biologics in severe asthma: the overlap endotype - opportunities and challenges

INTRODUCTION

Patients with severe asthma experience a significant burden of symptoms, disease exacerbations and medication side-effects. Severe asthma interferes with the patients' quality of life and has high health-care costs. New targeted biologic therapies have improved the management of severe asthma by significantly reducing exacerbations and maintenance corticosteroid use, and also improving lung function and patient quality of life.

AREAS COVERED

Not all severe asthmatics are eligible for such therapies. Those with allergic and eosinophilic asthma, usually referred to as 'T2-high' asthma benefit from anti-IgE and anti-IL-5/5 R antibodies respectively, whereas some asthmatics are eligible for both: 'overlap' endotype. In this review, we present briefly the monoclonal antibodies that have been approved in the management of severe asthma and we focus on the 'overlap' endotype.

EXPERT OPINION

Since these therapies are costly, it is extremely important to choose the right treatment for the right patient especially in the 'overlapping' one. The decision is mainly based on the judgment of the clinician and is often driven by the most easily obtainable biomarker, thus the blood eosinophil count. Comorbidities, patient's input and administration frequency may aid the decision of choosing one over another biologic.

Anti-IL-5 monoclonal antibodies for the treatment of asthma: an update

INTRODUCTION

Asthma exhibits marked heterogeneity in symptoms with severe or refractory asthma representing a clear area of unmet medical need. These patients require more specifically targeted treatments with monoclonal antibody-based biologics targeted at inhibition of the type 2 cytokines IL-4, IL-5 and IL-13 having considerable potential as effective treatments for severe asthma. For the most part, anti-cytokine-based biologic therapies are more likely to give significant clinical benefit in carefully selected patient populations that take asthma phenotypes and endotypes into account.

AREAS COVERED

This review is based on recent English-language original articles in Pub Med or MedLine that reported significant clinical findings on the current status, therapeutic potential and safety of the anti-IL-5 biologics mepolizumab, reslizumab and benralizumab in the treatment of severe refractory asthma.

EXPERT OPINION

Anti-IL-5 treatment appears effective in patients with eosinophilic asthma through exacerbation prevention with accumulating evidence of glucocorticoid-sparing effects with an acceptable safety profile for these biologics.