Australian Mepolizumab Registry (AMR)

The Australian Mepolizumab Registry (AMR) is an investigator-initiated, observational post-marketing surveillance registry of patients with severe refractory eosinophilic asthma undergoing mepolizumab (Nucala) therapy in Australia.  The AMR was established in January 2017 through the Australasian Severe Asthma Network (ASAN).

AMR recruitment is now closed and the database is a source for ongoing analyses.

Mepolizumab is a monoclonal antibody therapy that blocks the binding of interleukin-5 (IL-5) to its receptor, reducing the production and survival of eosinophils.  In clinical trials, mepolizumab treatment reduced hospitalisations by approximately 50% and has been demonstrated to have an oral-steroid sparing effect.

Purposes of the AMR:

1. Enable clinicians to document eligibility for mepolizumab treatment commencement and continuation,
2. Document drug-related adverse effects and severe adverse events,
3. Report on the magnitude of the problem of severe eosinophilic asthma, characteristics of this population and their management.

Clinicians were invited to enrol patients who underwent assessment for eligibility and commencement of mepolizumab treatment through the Pharmaceutical Benefits (PBS)-subsidised scheme, or outside of the scheme, during January 2017 to April 2024. The patients underwent an assessment at registration and were followed prospectively for up to 4 years.

Severe eosinophilic asthma in Australia – findings from the AMR

The AMR has provided useful information regarding the use and effectiveness of mepolizumab in real-world severe eosinophilic asthma in Australia.  Following the approval of mepolizumab treatment in Australia, more than 400 patients were registered in the AMR across 21 clinics.

The real-world data from AMR have confirmed the effectiveness of mepolizumab treatment in clinical practice, with patients experiencing reduction in asthma symptoms, fewer exacerbations, less ongoing OCS exposure, and improvements in lung function and health-related quality of life (Harvey et al. 2020, Thomas et al. 2021, Kritikos et al. 2023, Harvey et al. 2025).

• The disease burden in AMR patients is high. Comorbidities such as allergic rhinitis (63% of patients), gastro-oesophageal reflux disease (52%), obesity (46%) and nasal polyps (34%) were common. In AMR patients, the mepolizumab treatment continuation rate after 6 months was 86% (based on PBS continuation criteria). Mepolizumab treatment significantly reduced severe exacerbations (including oral corticosteroid treatment and hospitalisations), and improved asthma symptom control, lung function and health-related quality of life over 12 months. ‘Super-responders’ had a T2 phenotype and few comorbidities (Harvey et al. 2020).

• Comorbidities in severe eosinophilic asthma (such as nasal polyps, fungal sensitisation, obesity and asthma with overlapping chronic obstructive pulmonary disease) modify the clinical asthma phenotype. However, mepolizumab treatment is associated with comparable clinical improvements in the presence of comorbidities. Treatment effect may be enhanced in the presence of some comorbidities, such as nasal polyps (Kritikos et al. 2023)

• Patients in AMR experienced substantial oral corticosteroid (OCS) exposure prior to mepolizumab commencement. Mepolizumab treatment reduced ongoing OCS exposure (maintenance use, OCS burst for exacerbations, and cumulative OCS use) over a 24-month period (Thomas et al 2021, Harvey et al 2025). Notably, patients receiving mepolizumab treatment also experienced reductions in important clinically relevant and OCS related side-effects, including symptoms of depression and anxiety (Harvey et al. 2025)

• A subset of patients receiving mepolizumab treatment for severe eosinophilic asthma achieve clinical remission (Thomas et al. 2024). Clinical remission in patients receiving mepolizumab treatment has been explored and further characterised using data from the AMR (Hamada et al. 2024, Hamada et al. 2025, Hamada et al. 2025)

Dr Erin Harvey
Australasian Severe Asthma Network
Email: erin.harvey@newcastle.edu.au
Phone: +61 2 4042 0099

The AMR is supported by the GlaxoSmithKline Investigator-Sponsored Study scheme.