Connect Biopharma reports Phase 2 Seabreeze STAT data showing rademikibart improved FEV1 by 130 mL versus placebo at Day 7 in acute asthma.
Written By: Anshu Gupta, PharmD
Reviewed By: Pharmacally Editorial Team
Connect Biopharma reported topline Phase 2 Seabreeze STAT results showing that rademikibart produced a statistically significant 130 mL greater improvement in post-bronchodilator FEV1 at Day 7 versus placebo in adults and adolescents with asthma and type 2 inflammation. The treatment was also associated with an approximately 66% lower rate of treatment failure over 28 days, although the primary endpoint did not reach statistical significance.
Statistically Significant Improvement in Lung Function
The randomized, double-blind, placebo-controlled Seabreeze STAT Asthma study enrolled 160 participants experiencing an acute asthma exacerbation and with type 2 inflammation. Patients were randomized 1:1 to receive a single 600 mg subcutaneous dose of rademikibart (n=79) or placebo (n=81), in addition to standard of care.
The key secondary endpoint, absolute change from baseline in post-bronchodilator forced expiratory volume in one second (FEV1) at Week 1, showed a statistically significant improvement with rademikibart.
At Day 7, FEV1 increased by 250 mL from baseline with rademikibart compared with 120 mL with placebo, resulting in a 130 mL greater improvement versus placebo (p=0.023).
The company did not specify the individual components of background standard-of-care therapy in its topline announcement. Therefore, the relative contribution of systemic corticosteroids, inhaled corticosteroids, bronchodilators, or other acute-exacerbation treatments cannot be determined from the reported data.
Treatment Failures Fell 66%, but Primary Endpoint Was Not Significant
The study’s primary endpoint was treatment failure within 28 days of randomization. Treatment failure included death from any cause, asthma-related hospital readmission, emergency department or unscheduled medical visits for worsening symptoms, or the need to intensify pharmacologic treatment.
Rademikibart reduced the treatment-failure rate by approximately 66% compared with placebo. However, the difference did not reach statistical significance (p=0.153).
Connect attributed the result to an overall treatment-failure rate that was lower than projected. The company also reported a 50% reduction in emergency department visits or unscheduled medical visits for worsening asthma symptoms compared with placebo.
These findings indicate a numerical reduction in treatment failures, but the available topline data do not establish a statistically significant effect on the study’s primary endpoint.
IL-4Rα Blockade Targets Type 2 Inflammation
Rademikibart is a fully human monoclonal antibody targeting interleukin-4 receptor alpha (IL-4Rα), a shared receptor component of the IL-4 and IL-13 signaling pathways.
Blocking IL-4Rα inhibits signaling from both cytokines and suppresses type 2 inflammation, a pathway involved in diseases including asthma and other inflammatory respiratory conditions.
The Seabreeze STAT program is evaluating whether this mechanism can provide additional benefit when rademikibart is administered alongside standard treatment during acute respiratory exacerbations.
Safety Profile Remained Comparable to Placebo
Rademikibart was well tolerated through the study, with no new safety signals identified. Adverse events occurred at low frequency in both groups, and no individual adverse event was reported in more than two participants.
No adverse event led to treatment discontinuation in either arm. One serious adverse event occurred in the rademikibart group compared with three in the placebo group. No deaths were reported in either treatment group.
The reported safety findings therefore showed no major imbalance between rademikibart and placebo in this Phase 2 population.
COPD Data and FDA Engagement Are Next
Connect expects to report topline results from the ongoing Phase 2 Seabreeze STAT COPD study (CBP-201-207) later in September. The trial is evaluating rademikibart in patients with acute COPD exacerbations and type 2 inflammation.
Key development milestones include:
- COPD readout: Topline Phase 2 Seabreeze STAT COPD data are expected later in September 2026.
- FDA engagement: Connect plans to meet with the U.S. Food and Drug Administration following the COPD results to discuss alignment on a Phase 3 registrational program.
- Proposed asthma endpoint: The company has identified Week 1 post-bronchodilator FEV1 as the proposed primary endpoint for the Phase 3 asthma program.
- Potential development scope: The planned Phase 3 strategy could evaluate rademikibart as an add-on treatment for acute exacerbations of both asthma and COPD.
The Seabreeze STAT asthma results provide a statistically significant lung-function signal alongside a large but non-significant reduction in treatment failures. The forthcoming COPD data and subsequent FDA discussions will determine how these findings translate into the design and scope of the next-stage development program.
Reference
Connect Biopharma Announces Positive Preliminary Topline Data from its Global Phase 2 Study of Rademikibart as an Add-on Treatment for Acute Exacerbations in Adult and Adolescent Participants with Asthma and Type 2 Inflammation, 15 September 2026
Rademikibart Add-on Treatment of an Acute Asthma Exacerbation (Seabreeze STAT Asthma), ClinicalTrials.gov ID NCT06940141
About the Writer
Anshu Gupta (LinkedIn) is a PharmD professional and healthcare writer with interests in clinical research, pharmacovigilance, regulatory affairs, and medical writing. She has presented research at academic conferences and completed certifications in Good Clinical Practice (GCP), ICH-GCP, and drug safety. Passionate about clinical trials and evidence-based medicine, she is committed to translating scientific evidence into accurate, reliable, and accessible healthcare content.