Connect Biopharma (NASDAQ:CNTB) CEO Barry Quart told investors at Oppenheimer’s 36th Annual Healthcare Life Science Conference that the company is advancing its lead asset, rademikibart, into what it described as a novel treatment approach for acute exacerbations of asthma and chronic obstructive pulmonary disease (COPD). Quart said the company believes rademikibart’s binding characteristics and rapid effects on lung function could differentiate it from existing IL-4Rα–targeting therapies and from currently marketed asthma and COPD biologics, which are not indicated for acute exacerbations.
Rademikibart program overview and China partnership
Quart described rademikibart as a “next-generation IL-4 receptor alpha humanized monoclonal antibody” designed to target IL-4Rα, thereby affecting the IL-4 and IL-13 pathways. He said Connect has completed studies in atopic dermatitis and chronic asthma.
Focus on acute exacerbations in asthma and COPD
Quart framed acute exacerbations as a large, underserved market, arguing that care has seen little innovation. He cited high rates of exacerbations among asthma and COPD patients annually, with millions of emergency room visits and hospitalizations. He said there are no biologics approved for acute exacerbations and emphasized that existing biologics for asthma and COPD carry labeling that warns against use for treating acute exacerbations, which he argued could reduce direct competition in an acute-use setting.
Connect has initiated two enrolling studies: one in patients experiencing an acute asthma exacerbation and one in patients with an acute COPD exacerbation. Quart said results are anticipated “mid-year,” with a primary endpoint of treatment failure.
Mechanistic claims and differentiation versus dupilumab
Quart spent much of the presentation highlighting what he characterized as meaningful mechanistic differences between rademikibart and dupilumab (marketed as Dupixent). He said rademikibart binds to a different epitope and with a different orientation, closer to the receptor active site and more tightly, which he linked to higher internalization of the drug-receptor complex. He said this internalization could lead to fewer receptors on the cell surface and higher turnover of eosinophils.
In discussing clinical implications, Quart contrasted eosinophil behavior observed with dupilumab against rademikibart in asthma patients over 24 weeks. He said dupilumab has been associated with increases in eosinophils, while rademikibart showed a decrease (though he noted it was not as pronounced as IL-5–targeting therapies). Quart also pointed to reports of eosinophil-related serious adverse events for dupilumab in asthma in the FDA’s FAERS database, saying Connect does not expect to carry that “liability.”
Rapid onset data and airway function
Quart argued that rademikibart may have a rapid onset of improvement in airway function. He referenced results from a previously conducted Phase IIb chronic asthma study, highlighting improvements in FEV1 and noting that at the first clinic visit at one week the improvement was “highly significant.” He further said home spirometry suggested most of the benefit occurred by the next morning after dosing, “in less than 24 hours.” Quart said this rapid onset was a key rationale for pursuing acute exacerbation treatment, where speed of effect is critical.
He also presented preclinical data in cell culture and human airway slice models suggesting rademikibart could counteract IL-4 and IL-13–driven reductions in beta-agonist responsiveness. Quart said that in these models rademikibart shifted the beta-agonist dose-response back toward baseline, while dupilumab showed little to no effect in the same assays.
Study design, timelines, and commercial expectations
Quart said Connect’s Phase II acute exacerbation studies are designed around treatment failure and are expected to read out mid-year. He cited a recently published U.K. investigator study evaluating benralizumab in acute episodes, pointing to a high treatment failure rate at four weeks and stating that benralizumab did not show benefit in that setting, though it reduced new exacerbations over time. Quart suggested that if rademikibart can produce meaningful FEV1 improvements within hours to days, it could help keep patients out of the hospital and reduce the need for additional prednisone courses.
To potentially further accelerate onset, Quart said Connect is completing an intravenous (IV) study to assess safety, pharmacokinetics, and early lung function signals. He said the company found it could administer rademikibart as an IV push “very safely” and expects IV pharmacology data “this quarter,” with the goal of determining whether improvements in FEV1 can be seen faster than with subcutaneous dosing.
On commercialization, Quart said market research indicated “keen interest” in an acute treatment option, including a 40%–45% preference share among clinicians for patients not already receiving a biologic. He added that clinicians indicated they would maintain patients on the same drug chronically about 75% of the time after acute use, suggesting an acute indication could help drive chronic adoption.
In Q&A, Quart said Connect’s market research forecasts peak sales for acute and chronic asthma/COPD indications “upwards of $5 billion” globally. He said there is no established FDA guidance for acute exacerbation approvals because no drugs have been approved for that purpose, and Connect expects to meet with FDA after Phase II data to define a Phase III program. Quart said the agency views endpoints beyond two weeks as new exacerbations, and he anticipates a Phase III program could involve a combination of FEV1 and treatment failure in the first couple of weeks. He said the acute Phase III program could potentially be completed “in the one year neighborhood” from start to finish and would likely require two studies.
Quart also said Connect already has agreements with FDA on a Phase III program for chronic asthma. He added that with a positive Phase III in China and existing global Phase II data, the company may only need a “modest bridging study” for chronic use, noting that China uses the same GINA guidelines for treatment.
Finally, Quart said Connect has cash into 2027 and described the company’s upcoming catalysts as including preclinical data shared early in the year, IV pharmacology data expected in the next month, and mid-year readouts from the Phase II acute exacerbation studies.
About Connect Biopharma (NASDAQ:CNTB)
Connect Biopharma Holdings Ltd. is a clinical-stage biopharmaceutical company focused on the discovery and development of monoclonal antibody therapies for immune-mediated disorders. Headquartered in Singapore with a research and commercial presence in the United States, the company applies proprietary technology platforms to target novel pathways in inflammatory and autoimmune diseases.
The company’s lead product candidate, CBP-201, is a fully human monoclonal antibody that antagonizes the interleukin-31 receptor, a key mediator of chronic pruritus in conditions such as atopic dermatitis and prurigo nodularis.
