Can Patients with CSU Achieve True Remission?
True remission in chronic spontaneous urticaria (CSU) is a realistic goal, but the field lacks the longitudinal data and validated biomarkers to reliably identify which patients will get there, according to Jonathan Bernstein, MD, professor of medicine at the University of Cincinnati and physician with Bernstein Allergy Group and the Bernstein Clinical Research Center.
Bernstein presented on endotyping and biomarker strategies in CSU at the 2026 Eastern Allergy Conference (EAC) in Palm Beach, Florida, and spoke with HCPLive about where the pipeline stands and what clinicians can apply now.
Read parts 1 and 2 of the interview with Bernstein here: Endotyping & Biomarkers in CSU, With Jonathan Bernstein, MD and Sequencing Emerging Therapies in CSU, With Jonathan Bernstein, MD
Which Agents Have the Best Shot at Inducing Remission?
Among emerging therapies, Bernstein cited remibrutinib, a BTK inhibitor positioned further downstream in the disease pathway, as a candidate with plausible mechanistic grounds for inducing remission. C-kit inhibitors were also flagged as potentially meaningful given their action on mast cells, the primary effector cells in CSU. By contrast, Bernstein said he would not expect dupilumab or omalizumab to accelerate remission.
"We don't have that information yet," he noted, adding that well-designed studies examining time course and patient-level predictors of remission are still absent from the literature.
Complicating the picture further: distinguishing drug-induced remission from spontaneous remission remains an unresolved methodological challenge. The World Allergy Organization Urticaria Committee has proposed defining CSU clinical remission as total resolution of urticaria signs and symptoms without pharmacotherapy for ≥ 6 months, though the implications of this definition in clinical practice must still be evaluated and validated in future studies.1 Current data show no significant difference in CSU relapse between 6- and 12-month periods of remission.
Biomarker Implementation: Where the Gaps Are
On the barriers to routine biomarker use, Bernstein pointed to 3 core problems: lack of validation, unclear cut points, and uncertain predictive value across treatment responders and non-responders.
He highlighted the CU index as a specific example, which is not yet validated and primarily reflective of basophil activity rather than mast cell behavior. Because mast cells are tissue-based and represent a distinct lineage from basophils, translating basophil-derived assay data to clinical decision-making has limits.
Composite immunological signatures integrating multiple biomarkers hold promise for guiding therapeutic decisions, and implementing validated markers could enable earlier identification of difficult-to-treat patients and more targeted therapy.2 But that infrastructure is not yet in place.
The Clinical Takeaway: Use What You Have
Bernstein's message to clinicians leaving EAC: patients with CSU are diverse, and better phenotyping, even with imperfect tools, supports more productive patient conversations.
"Do we have the right biomarkers yet? Not necessarily," Bernstein said. "Do the ones we have add to the conversation with our patients? They certainly do. That’s where I think clinicians should take advantage of this, and I think it might also be more gratifying when you're treating patients to know that you can really give them some additional guidance in terms of treatment expectations and outcomes.”
Editor’s note: SANOFI-AVENTIS U.S., Pharming Healthcare, Novartis Pharmaceuticals Corporation, BioCryst Pharmaceuticals, Regeneron Healthcare Solutions, CSL Behring, Blueprint Medicines Corporation, Dermavant Sciences, Incyte Corporation, Eli Lilly and Company, and more.
References
Sánchez J, Pite H, Gómez RM, et al. Chronic spontaneous urticaria remission definition and therapy stepping down: World Allergy Organization position paper. J Allergy Clin Immunol. 2025;155:1050–1056. https://www.jacionline.org/article/S0091-6749(24)02413-8/abstract
Calzari P, Favale EM, Cugno M, et al. Predictors of early treatment response to antihistamines and omalizumab in chronic spontaneous urticaria. Front Allergy. 2026. doi:10.3389/falgy.2025.1728559. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12832613/
