Connect Biopharma presented new post-hoc analyses at ERS 2025 showing that rademikibart, its investigational anti–IL-4Rα antibody, delivered rapid and sustained lung function gains and reduced exacerbations in moderate-to-severe asthma, with the strongest effects in patients with elevated type 2 inflammatory markers. In a 24-week readout, pre-bronchodilator FEV1 improvements reached 507 ml in patients with both high eosinophils and high FeNO, versus 108 ml in those with low levels of both biomarkers. Exacerbation rates fell by 63% in patients with high eosinophils and 69% in those with high FeNO. A companion analysis flagged regional variability in treatment and placebo responses — notably higher placebo gains and milder baseline disease in Polish sites — informing site selection and conduct for the company’s ongoing Seabreeze STAT phase 2 studies in acute exacerbations of asthma and COPD, with topline data expected in the first half of 2026.
The strategic signal is clear: this program is being positioned to challenge or complement the incumbency of IL-4/IL-13 pathway blockade in chronic asthma by moving earlier into the acute care window. If rademikibart can show fast-onset efficacy in emergency and hospital settings, the drug could redefine when and how biologics are deployed — shifting from maintenance-only to intervention during flares. That ambition raises a practical question for commercial and medical teams: can a biomarker-driven biologic be operationalized at the point of care where speed, logistics, and payer rules dominate decision-making?
For patients and HCPs, the biomarker gradient matters. FeNO and blood eosinophils are widely accessible and increasingly embedded in treatment algorithms; enrichment signals that correlate with larger FEV1 gains and fewer exacerbations support precision prescribing and a cleaner health-economic story. Payers will expect that precision to translate into measurable reductions in admissions, steroid exposure, and resource use, especially if Seabreeze demonstrates benefit with single- or few-dose regimens during acute episodes. The regional variability observed in the phase 2b analysis underscores the importance of rigorous site management and baseline balance; it also foreshadows payer and HTA scrutiny of generalizability and real-world performance across diverse care settings.
The competitive context is crowded and shifting. Dupilumab set the standard in IL-4Rα blockade and is expanding into COPD with type 2 signatures; tezepelumab and anti–IL-5 class agents continue to fragment the severe asthma market by phenotype. To win share, Rademikibart must either outperform on efficacy in defined biomarker strata, deliver a meaningfully faster onset, or open the acute exacerbation setting where incumbents have limited footholds. The China partnership with Simcere hints at a regional go-to-market strategy that could accelerate access and RWE generation, while global commercialization will hinge on payer-aligned biomarker cutoffs, streamlined diagnostics, and care-pathway integration in ED and inpatient environments.
The broader industry trend is unmistakable: immunology programs are converging on biomarker-enriched populations, with sponsors using post-hoc signals to fine-tune development and de-risk pivotal plans, while operational discipline at the site level becomes a competitive advantage. With Seabreeze readouts targeted for 1H26, the next inflection will test whether an IL-4Rα backbone can credibly migrate into acute care and deliver a differentiated value proposition before label expansions and potential biosimilar pressure reshape pricing power. The strategic question now is whether Rademikibart can translate promising subgroup signals into a clinically decisive, operationally feasible, and payer-compelling acute exacerbation strategy that reorders the biologics playbook in respiratory disease.
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Jon, a computer data scientist, focuses on the latest clinical trial industry news and trends.
