Connect Biopharma reports positive Phase 1 rademikibart data

Connect Biopharma Holdings (NASDAQ:CNTB), a clinical-stage biopharmaceutical company focused on chronic inflammatory diseases, today reported positive topline preliminary results from its Phase 1 clinical pharmacology study (CBP-201-105) evaluating an intravenous (IV) formulation of rademikibart.

The data suggest that rademikibart—an antibody targeting interleukin-4 receptor alpha (IL-4Rα)—may possess unique bronchodilatory properties that act independently of its anti-inflammatory mechanism.

The study evaluated a single 300 mg dose of rademikibart administered via a 2-minute IV push in adult patients with stable asthma and stable COPD.

During the trial, patients experienced lung function improvements (FEV1) of 100 mL to over 400 mL as early as 15 minutes post-dosing.

This is substantially faster than the onset observed with traditional 600 mg subcutaneous administration.

Mean FEV1 improvements of 200–400 mL were generally maintained through Day 29 in both the asthma and COPD cohorts, while placebo groups trended downward.

Elsewhere, rademikibart was well-tolerated with no serious or severe adverse events, and no patients discontinued the study due to treatment-related issues.

Current standard of care for acute exacerbations relies heavily on β-agonist bronchodilators and systemic steroids.

Rademikibart’s ability to provide immediate physical relief while simultaneously addressing the underlying Type 2 inflammatory drivers could position it as a best-in-class option for both acute and chronic respiratory care.

Connect Biopharma remains on track to report topline data from its ongoing Phase 2 Seabreeze STAT studies in mid-2026.

Following those results, the company plans to engage with the U.S. FDA to align on the requirements for a pivotal Phase 3 program.