A new PBS-listed biologic offers an option for a select group of patients with uncontrolled COPD and GPs could play a key role in finding them.
The arrival of mepolizumab (Nucala, GSK) on the PBS this month represents both a new treatment paradigm for COPD and a targeted option for a relatively small group of patients with severe disease, according to respiratory physician Professor Gregory King.
Mepolizumab has been PBS listed as an add-on to optimised triple inhaler therapy for adults with uncontrolled COPD, an eosinophilic phenotype defined by blood eosinophils of at least 300 cells/µL, and a history of at least one severe or two moderate exacerbations in the previous 12 months.
At least one moderate or severe exacerbation must have occurred while the patient was taking optimised triple therapy.
Professor King, head of respiratory medicine at Royal North Shore Hospital and research leader at the Woolcock Institute of Medical Research, told The Medical Republic the listing was significant because COPD treatment had changed relatively little for many patients.
“I would say a bit of both,” he said when asked whether mepolizumab represented a genuine paradigm shift or an option for a particular subgroup.
It was aimed at a “very specific subgroup” but was also a change in approach because it targeted COPD exacerbations, particularly in patients experiencing frequent or serious episodes.
“This is the first time we’re going to use something very different that has actually been shown to have a material effect on that exacerbation risk,” Professor King said.
Mepolizumab is a monoclonal antibody targeting IL-5-mediated eosinophilic inflammation. The phase 3 MATINEE trial included patients with COPD taking triple inhaled therapy who had an eosinophil count of at least 300 cells/µL at screening and a history of frequent exacerbations. Patients with current or previous asthma were excluded.
The trial found a 21% reduction in the annualised rate of moderate or severe exacerbations with mepolizumab compared with placebo, at 0.80 versus 1.01 events per year. Time to first moderate or severe exacerbation was also significantly longer.
While GPs can’t independently prescribe the biologic, Professor King said they had an important role to play in helping to identify patients who might benefit from the therapy.
The key was identifying patients who might qualify and ensuring the information needed by the respiratory specialist accompanied the referral, he said.
“The eosinophil counts certainly do fluctuate,” he said.
“The higher the eosinophil counts, the more likely this is going to be to work because, after all, it’s an anti-eosinophil drug.”
The relevant threshold was 300 cells/µL, or 0.3 × 10⁹/L as commonly reported by Australian pathology laboratories, he said.
Patients hovering around the threshold were potentially less likely to derive substantial benefit than those with clearly elevated eosinophils and a substantial exacerbation burden.
“The bigger the problem you’re treating, the more potential benefit you’re going to get,” Professor King said.
GP records could be particularly valuable because eosinophil measurements taken over time may establish a clearer picture than a single result.
“GPs can certainly really help if they just collate the history of eosinophil counts,” Professor King said.
“GPs will often monitor the blood counts for whatever reason. So just having a history of the eosinophil counts and a pathology printout that is attached to a referral letter is always really helpful.”
The referral should ideally also include any previous spirometry and a clear history of exacerbations, particularly courses of prednisone and antibiotics.
Professor King said even approximate dates were useful, because otherwise specialists were often dependent on patients remembering when exacerbations occurred.
“If there’s any records of spirometry … that’s really helpful because it’s there for us,” he said.
“What would be really helpful is the dates, rough dates even, that they had prednisone [or] were prescribed antibiotics.”
Determining whether the biologic is working may be more difficult in COPD than in severe asthma, where patients can sometimes report improvement relatively quickly.
In COPD, the principal target is exacerbations rather than a marked improvement in day-to-day symptoms or lung function, meaning response may need to be assessed over six to 12 months, Professor King said.
That also made accurate baseline documentation particularly important.
“You can’t go by how they feel,” Professor King said.
“It’s not a lung function change we’re looking at either. It’s purely these exacerbations, and they could occur two or three times a year.”
He said careful specialist assessment and monitoring were important, but noted that access to respiratory specialists, however, could become a significant barrier, particularly for patients in rural areas and parts of major cities.
“If you can afford to see someone in private, you can probably access it pretty quickly if it’s appropriate,” Professor King said.
“But if you wait for a public appointment, you’re going to wait a long time.”
Related
Mepolizumab should be prescribed by a specialist physician, or by a healthcare professional in consultation with a specialist experienced in diagnosing and treating COPD. The recommended dose is 100mg subcutaneously every four weeks.
Professor King said the practical message for GPs was to revisit the records of patients who continued to exacerbate despite treatment.
If a patient had presented to emergency or been admitted with a COPD exacerbation, GPs should examine their previous eosinophil counts, he said.
“If they’re above 0.3 or 300, whichever units we’re using, then consider sending [them] to a respiratory specialist for consideration of a biologic and tabulate their history of exacerbation,” he said.
For patients who had not been hospitalised, GPs could look further back through the clinical record and count exacerbations requiring additional treatment, particularly prednisone.
His final advice was for GPs to become familiar with the eligibility requirements rather than waiting until a potentially eligible patient reached the specialist.
Professor King said the PBS listing of the therapy was significant as it was the first biologic to be subsidised by the scheme for COPD.
“One of the challenges in COPD management is that some patients continue to experience exacerbations despite triple inhaler therapy,” he said.
“These exacerbations can be severe, lead to hospitalisation, impair lung function and have a significant impact on quality of life.”
In Australia, COPD places a substantial burden on the Australian health system. It is a leading cause of preventable hospitalisations in Australia.
More than 68,000 COPD-related hospital stays occurred in 2023–2024 that could have potentially been prevented, according to the Lung Foundation of Australia.
Over this period, the Australian health system spent an estimated $1.8 billion on COPD, Australian Institute of Health and Welfare data reveals.
Dr Sebastian DiNatale, Medical Affairs Director, Respiratory at GSK Australia welcomed the PBS listing.
“People living with uncontrolled COPD continue to face significant challenges despite optimised inhaled triple therapy,” he said.
“We are delighted to see NUCALA become the first PBS listing for a biologic for uncontrolled eosinophilic COPD, offering eligible Australians an additional treatment option.”
