EMBARC and Insmed to run 3,000-patient brensocatib study
The European Multicentre Bronchiectasis Audit and Research Collaboration (EMBARC) has announced its intention to partner with Insmed Incorporated on a large-scale interventional study of brensocatib in bronchiectasis, adding substantial long-term evidence to a drug that gained regulatory approval on the back of the ASPEN trial.
The planned study will enrol up to 3,000 patients across the United Kingdom, Spain, Germany, Belgium, France, and Italy in an open-label, single-arm design running over three years. The primary scientific question is whether brensocatib 25 mg, an oral reversible inhibitor of dipeptidyl peptidase-1 (DPP-1), can do more than slow disease progression and instead modify the underlying trajectory of the condition when used earlier in the disease course. Endpoints will include established validated measures as well as novel composite endpoints, though the full endpoint package has not yet been disclosed.
The announcement was made at the World Bronchiectasis Conference in Hannover on 25 June 2026.
The scientific rationale
Brensocatib works by inhibiting DPP-1, the enzyme responsible for activating neutrophil serine proteases implicated in the chronic airway inflammation that characterises bronchiectasis. The ASPEN Phase 3 trial, which underpinned the drug's regulatory journey, showed that brensocatib 25 mg reduced exacerbation frequency, slowed lung function decline, and produced structural airway changes.
Lead study investigator James Chalmers, Rhodes Chair of Experimental Therapeutics and Respiratory Physician at the University of Oxford, said the new study will ask "whether intervening earlier in the disease course can do more than slow progression, but fundamentally alter its trajectory." He described the three-year horizon as a genuine opportunity to assess whether brensocatib can "change the natural course of the disease."
Martina Flammer, Chief Medical Officer at Insmed, said the collaboration reflects the company's commitment to understanding "how brensocatib can make the greatest possible difference in patients' lives," noting the value of studying the drug in a large, heterogeneous real-world population.
Market and regulatory context
Bronchiectasis is a chronic, progressive inflammatory lung disease causing permanent airway widening, persistent bacterial infections, and recurrent pulmonary exacerbations. It affects approximately 600,000 people in Europe and millions worldwide. Until recently it was a condition with no approved disease-modifying pharmacotherapy; the arrival of brensocatib represented a significant shift in the treatment landscape.
The intended study is structured as a long-term post-approval evidence generation exercise, a design increasingly favoured by regulators including the EMA and MHRA as a condition of, or complement to, marketing authorisation in disease areas where long-term modification claims require prospective demonstration. For Insmed, a positive dataset from this study could support label expansion and strengthen prescribing guidelines, particularly for patients earlier in their disease course who are not yet experiencing frequent exacerbations.
The DPP-1 inhibitor class remains lightly populated at the clinical level, giving Insmed a meaningful first-mover advantage in bronchiectasis. Other companies are advancing neutrophil-targeted and anti-inflammatory approaches in chronic lung disease, but none has yet matched the late-stage data package that Insmed has assembled. How durable that position is will depend in part on whether this study can substantiate a disease-modification claim, which would represent a substantially higher commercial and clinical bar than exacerbation reduction alone.