A phase 3 trial of Brensocatib — a small molecule, oral, reversible inhibitor of dipeptidyl peptidase 1 (DPP1) — revealed significant benefits for bronchiectasis patients.
RT’s Three Key Takeaways
- Brensocatib efficacy: The Phase 3 ASPEN trial demonstrated that brensocatib significantly reduced the rate of pulmonary exacerbations in patients with non-cystic fibrosis bronchiectasis compared to placebo, marking a potential breakthrough in treating a disease with no approved therapies.
- Impact on lung function: Brensocatib not only reduced exacerbations but also slowed lung function decline and increased the proportion of patients who remained exacerbation-free over 52 weeks.
- Regulatory and clinical significance: Brensocatib is under FDA Priority Review and, if approved, could become the first therapy specifically for bronchiectasis and the first approved DPP1 inhibitor for neutrophil-mediated diseases.
Results from a phase 3 ASPEN study revealed brensocatib significantly reduced the rate of pulmonary exacerbations in patients with non-cystic fibrosis bronchiectasis compared to placebo and also slowed lung function decline.
The ASPEN study, published in the New England Journal of Medicine (NEJM) is the largest clinical trial ever conducted in bronchiectasis, a serious, chronic, and progressive inflammatory pulmonary disease that today has no approved therapies.
“Bronchiectasis is a debilitating disease characterized by pulmonary exacerbations, which contribute to lung function decline and severely impact quality of life,” said lead author James Chalmers, MBChB, PhD, Professor and Consultant Respiratory Physician at the School of Medicine, University of Dundee, UK. “With limited treatment options and no approved therapies, the burden of exacerbations remains high, with many patients experiencing multiple episodes each year. For the first time, the ASPEN data published in NEJM demonstrates that a treatment which targets inflammation can reduce exacerbations and slow the rate of lung function decline. This is an exciting development and represents a potentially transformative breakthrough for people living with bronchiectasis, offering new hope for patients with this challenging condition if brensocatib is approved.”
As previously reported, the ASPEN study met its primary endpoint, with both brensocatib doses achieving statistical and clinical significance for the reduction in the annualized rate of pulmonary exacerbations versus placebo over the 52-week treatment period. The annualized rate of exacerbations was 1.02 for brensocatib 10 mg, 1.04 for brensocatib 25 mg, and 1.29 for placebo. These rates were significantly lower in the brensocatib 10 mg and 25 mg groups versus placebo with rate ratios of 0.79 (adjusted P=0.004) and 0.81 (adjusted P=0.005), respectively.
Both dosage strengths of brensocatib also met several exacerbation-related secondary endpoints, including significantly prolonging the time to first exacerbation and significantly increasing the proportion of patients remaining exacerbation-free over the treatment period. Patients treated with brensocatib 25 mg also showed significantly lower lung function decline at week 52 as measured by post-bronchodilator forced expiratory volume over one second (FEV1).
Brensocatib was well-tolerated in the study. Treatment-emergent adverse events (TEAEs) occurring in at least 5.0% of patients treated with either dose of brensocatib and more frequently than in placebo were COVID-19 (15.8%, 20.9%, 15.8%), nasopharyngitis (7.7%, 6.3%, 7.6%), cough (7.0%, 6.1%, 6.4%), and headache (6.7%, 8.5%, and 6.9%) for brensocatib 10 mg, brensocatib 25 mg, and placebo, respectively.
“Currently, people with bronchiectasis have no approved treatments to address the frequent, damaging exacerbations that are the hallmark of this disease,” said Martina Flammer, M.D., MBA, Chief Medical Officer of Insmed. “Brensocatib has the potential to be the first approved therapy to fill this critical unmet need in the care of patients with bronchiectasis, as well as the first approved dipeptidyl peptidase 1 (DPP1) inhibitor—a new mechanism of action with the potential to address a range of neutrophil-mediated inflammatory diseases. The ASPEN trial represents a transformative step forward for the millions of people globally diagnosed with bronchiectasis.”
Brensocatib is currently under Priority Review with the U.S. Food and Drug Administration, with a target action date of August 12, 2025, under the Prescription Drug User Fee Act (PDUFA).
About ASPEN
The total number of active sites in ASPEN was 391 sites in 35 countries. Adult patients (ages 18 to 85 years) were randomized 1:1:1 and adolescent patients (ages 12 to <18 years) were randomized 2:2:1 for treatment with brensocatib 10 mg, brensocatib 25 mg, or placebo once daily for 52 weeks, followed by 4 weeks off treatment. The primary efficacy analysis included data from 1,680 adult patients and 41 adolescent patients.
About Bronchiectasis
Bronchiectasis is a serious, chronic lung disease in which the bronchi become permanently dilated due to a cycle of infection, inflammation, and lung tissue damage. The condition is marked by frequent pulmonary exacerbations requiring antibiotic therapy and/or hospitalizations. Symptoms include chronic cough, excessive sputum production, shortness of breath, and repeated respiratory infections, which can worsen the underlying condition. Today, approximately 500,000 patients in the U.S., 600,000 patients in the EU5 (France, Germany, Italy, Spain, and UK), and 150,000 patients in Japan have been diagnosed with bronchiectasis, and there are currently no approved therapies specifically targeting bronchiectasis in these regions.
About Brensocatib
Brensocatib is a small molecule, oral, reversible inhibitor of dipeptidyl peptidase 1 (DPP1) being developed by Insmed for the treatment of patients with bronchiectasis, chronic rhinosinusitis without nasal polyps, hidradenitis suppurativa, and other neutrophil-mediated diseases. DPP1 is an enzyme responsible for activating neutrophil serine proteases (NSPs), such as neutrophil elastase, in neutrophils when they are formed in the bone marrow. Neutrophils are the most common type of white blood cell and play an essential role in pathogen destruction and inflammatory mediation. In chronic inflammatory lung diseases, neutrophils accumulate in the airways and result in excessive active NSPs that cause lung destruction and inflammation. Brensocatib may decrease the damaging effects of inflammatory diseases such as bronchiectasis by inhibiting DPP1 and its activation of NSPs. Brensocatib is an investigational drug product that has not been approved for any indication in any jurisdiction.
