St. Vincent’s University Hospital leads European breakthrough in Rare Lung Disease trial

28th August 2025

New therapy offers life-changing alternative to invasive treatment for patients in Ireland 

St. Vincent’s University Hospital (SVUH), was one of the lead global sites in a landmark clinical trial published in the New England Journal of Medicine that could transform how a rare and debilitating lung disease is treated in Ireland.

The IMPALA-2 trial, the largest and most comprehensive study ever conducted in autoimmune pulmonary alveolar proteinosis (autoimmune PAP), found that an inhaled therapy – molgramostim – significantly improves lung function, breathlessness and quality of life. Until now, the only treatment option has been whole lung lavage, an invasive procedure requiring general anaesthetic and hospitalisation.

Led in Ireland by Professor Cormac McCarthy, Consultant Respiratory Physician at SVUH and Associate Professor at UCD, the trial signals a major breakthrough in how this life-limiting disease can be diagnosed and treated. This study would not have been possible without the expertise and support of the UCD Clinical Research Centre, which played a key role in enabling patient participation and trial delivery.

“This is the first treatment that targets the root cause of autoimmune PAP and it’s delivered through a simple inhaler, “said Prof McCarthy. “For patients in Ireland, this could mean fewer hospital stays, easier breathing and a genuine improvement in day-to-day life. It’s a transformative step forward.”

Affecting around seven people per million, autoimmune PAP is a rare condition where the immune system blocks a protein the lungs need to stay clean and healthy. This causes a sticky substance to build up in the lungs, making it harder to breathe and leading to constant tiredness – and in some cases, permanent lung damage or the need for a transplant.

“There are currently no approved treatments and many patients wait up to seven years for a correct diagnosis,” Prof McCarthy added. “By establishing SVUH as an expert centre in this disease, we can now shorten that diagnostic journey, offer access to therapy and support patients with the specialist care they need.”

The 48-week randomised trial, conducted across 43 centres in 16 countries, found that daily inhaled molgramostim significantly improved lung gas exchange, increased exercise capacity and reduced the need for whole lung lavage. The treatment was well tolerated, with minimal side effects.

“We’re proud that St. Vincent’s University Hospital was selected as a lead European site and played a key role in this landmark study,” said Prof McCarthy. “It shows that Ireland can lead on complex, rare disease research and most importantly that patients in Ireland can benefit directly from global breakthroughs right here at home.”

Ireland’s role in this pivotal study also strengthens its standing in ERN-Lung, the European Reference Network for rare respiratory diseases and reinforces SVUH’s position as a national centre of excellence for complex respiratory conditions.

“This is a milestone moment for patients living with autoimmune PAP,” Prof McCarthy concluded. “It’s about better care, earlier answers, and real hope for patients who have waited far too long.”

–ENDS –

Note to editor:

• Autoimmune PAP is caused by autoantibodies that block GM-CSF, leading to a build-up of surfactant in the lungs and impaired gas exchange.
• The disease affects 7 people per million, has no currently approved treatment and patients often wait up to 7 years for diagnosis.
• Molgramostim is an investigational inhaled therapy that restores the lungs’ ability to clear surfactant naturally.
• The IMPALA-2 trial is a Phase 3, 48-week, double-blind, placebo-controlled trial run across 43 sites in 16 countries.
• SVUH was a lead European site, with Prof Cormac McCarthy serving as Principal Investigator for Ireland.
• Results showed statistically and clinically meaningful improvements in:
  • DLco% (lung gas transfer)
  • Quality of life scores
  • Exercise capacity (peak METs)
  • Reduced need for lavage and hospitalisation
• SVUH is a designated centre within ERN-Lung, Europe’s network for rare respiratory disease expertise.