KalVista Pharmaceuticals Highlights EKTERLY® (Sebetralstat) as a Transformative Oral On-Demand Therapy for Hereditary Angioedema in Europe
KalVista Pharmaceuticals, Inc. (Nasdaq: KALV), a clinical-stage biotechnology company focused on developing innovative therapies for hereditary angioedema (HAE) and related disorders, today unveiled compelling new data from its KONFIDENT and KONFIDENT-S clinical studies of EKTERLY® (sebetralstat), the first and only oral on-demand therapy for HAE. The data were presented at the 20th German Allergy Congress (DGAKI) in Düsseldorf, Germany, held from October 2–4, 2025.
EKTERLY has been designed to offer a convenient, non-injectable option for patients managing acute HAE attacks. Across multiple ePoster presentations at DGAKI, EKTERLY demonstrated the ability to rapidly halt the progression of HAE attacks, provide fast symptom relief, and address the practical challenges associated with injectable therapies, which have historically limited timely treatment. Complementing these clinical findings, survey data from German patients underscored the persistent unmet need for accessible, innovative oral on-demand therapies across Europe.
Transforming the Management of Hereditary Angioedema in Europe
“The data presented at DGAKI underscore the transformative potential of EKTERLY for individuals living with HAE and highlight the urgent need for innovative treatment options across Europe,” said Paul Audhya, MD, MBA, Chief Medical Officer of KalVista Pharmaceuticals. “As we have observed in the United States, many patients delay or avoid treating acute attacks due to the practical limitations of injectable therapies, including injection-site reactions, difficulty carrying and storing medications, and challenges with self-administration. An oral on-demand therapy can empower patients to take control of their condition, allowing earlier intervention for more attacks, which is critical for reducing severity and improving outcomes.”
Dr. Audhya further noted that EKTERLY has now been approved in the European Union, marking a pivotal step forward for HAE care in Europe. Germany will serve as the initial launch market in the current quarter, with additional European launches planned throughout 2026 and beyond, ensuring broader access to this innovative therapy.
Barriers to Timely Treatment of HAE in German Patients
A dedicated survey of barriers to HAE treatment in German patients was presented by Thomas Buttgereit, MD, Specialist in Dermatology and Venereology, with additional qualifications in Allergology. Dr. Buttgereit serves as Head of the Clinical Trial Center, Institute of Allergology, Charité-Universitätsmedizin Berlin, a corporate member of Freie Universitätsmedizin Berlin and Humboldt-Universität zu Berlin, and is affiliated with the Fraunhofer Institute for Translational Medicine and Pharmacology (ITMP), Immunology and Allergology, Berlin.
The survey evaluated 49 German respondents who had treated at least one HAE attack with an approved on-demand therapy in the prior three months. Key findings included:
- Mean time to treatment: 3.9 hours, with only 18% of patients administering therapy within one hour of attack onset. Delays were strongly associated with longer and more severe attack durations.
- Injection-site reactions: 53% of respondents experienced adverse reactions at injection sites, including 33% of those receiving intravenous therapy and 94% of those receiving subcutaneous therapy.
“These survey findings reflect a recurring challenge in clinical practice,” Dr. Buttgereit explained. “Many patients postpone treatment due to the limitations of injectable therapies, which not only prolong discomfort but also increase the risk of severe complications. An oral on-demand therapy like sebetralstat could effectively overcome these barriers, enabling patients to intervene earlier and ultimately improving clinical outcomes.”
Rapid Attack Control with Sebetralstat
The pivotal data on sebetralstat’s ability to halt HAE attack progression were presented by Markus Magerl, MD, Professor of Dermatology and Allergy, Institute of Allergology, Charité-Universitätsmedizin Berlin, and Fraunhofer ITMP. These analyses drew on results from both the KONFIDENT and KONFIDENT-S trials.
Sebetralstat demonstrated a median time to halting attack progression of just 20 minutes across trials, highlighting its rapid efficacy. Early intervention was associated with reduced morbidity and a decreased burden of disease.
“These results are highly encouraging,” said Dr. Magerl. “In both the pivotal KONFIDENT trial and the KONFIDENT-S extension, sebetralstat consistently stopped attack progression in under 20 minutes. Rapid control is critical for patients with HAE because it directly minimizes attack severity, shortens duration, and reduces the risk of life-threatening complications. The ability to achieve such control across diverse attacks represents a meaningful advance in acute HAE management.”
Interim Analysis of KONFIDENT-S in European Participants
Additional insights were shared by Petra Staubach, MD, Senior Physician and Managing Director of the Clinical Research Center, Department of Dermatology and Allergy, University Medical Center Mainz, Germany. The interim analysis from KONFIDENT-S involved 69 participants from 15 European countries who collectively treated 999 HAE attacks with sebetralstat.
Key observations from this analysis include:
- Rapid treatment: Median time to treatment was 16 minutes overall and just 10 minutes in adolescents aged 12–17.
- Attack severity at treatment: 35% of attacks were still classified as mild at the time of administration.
- Time to symptom relief: Median time to onset of symptom relief was 1.6 hours.
- Tolerability: Sebetralstat was well-tolerated, with minimal adverse effects, supporting its use as a convenient and patient-friendly oral therapy.
“These data demonstrate that sebetralstat enables rapid, effective treatment of HAE attacks in a real-world European population,” Dr. Staubach remarked. “The consistency of its performance across age groups and countries reinforces the potential of this oral therapy to change the standard of care for patients living with HAE.”
Full access to all ePoster presentations from DGAKI is available on the KalVista website under the Publications section.
Understanding Hereditary Angioedema
Hereditary angioedema (HAE) is a rare, potentially life-threatening genetic disorder characterized by recurrent episodes of swelling in various tissues, including the extremities, face, gastrointestinal tract, and airway. HAE is caused by a deficiency or dysfunction of the C1 esterase inhibitor (C1INH) protein, leading to uncontrolled activation of the kallikrein-kinin system. This results in the excessive production of bradykinin, a peptide responsible for vascular permeability and fluid accumulation, which manifests clinically as painful and debilitating swelling.
HAE attacks can vary widely in severity and location but are frequently associated with intense pain, gastrointestinal symptoms, disfigurement, and, in cases of laryngeal involvement, life-threatening airway obstruction. The unpredictable nature of attacks significantly impacts quality of life, limiting daily activities and causing psychological stress for patients and their families.
Current Treatment Landscape and Limitations
Guidelines for the management of HAE emphasize the importance of early, on-demand treatment for all acute attacks, regardless of location or severity. Historically, on-demand therapies have consisted primarily of injectable agents, including intravenous (IV) or subcutaneous (SC) C1INH replacement or kallikrein inhibitors. While these therapies are clinically effective, they present practical challenges that can delay treatment initiation:
- Complex administration: Injectable therapies require proper technique and, in some cases, assistance from caregivers or healthcare professionals.
- Injection-site reactions: Pain, swelling, and redness at injection sites are common and may discourage timely use.
- Limited portability and storage requirements: Many injectable therapies necessitate refrigeration and careful handling, making them less convenient for on-the-go administration.
- Psychological barriers: Needle aversion and anxiety around injections contribute to delayed or avoided treatment.
These challenges have led to a significant unmet need for alternative treatment modalities that are both rapid-acting and patient-friendly.
EKTERLY®: A Novel Oral Option
Sebetralstat, marketed as EKTERLY®, addresses these limitations as the first oral on-demand therapy for HAE. Its design allows for rapid absorption and onset of action, offering patients a non-invasive option to treat attacks promptly. The KONFIDENT and KONFIDENT-S studies have demonstrated that EKTERLY can:
- Halt attack progression in under 20 minutes in a majority of cases.
- Deliver symptom relief within a median of 1.6 hours, significantly shortening the duration of attacks.
- Overcome practical barriers associated with injectable therapies, enhancing patient adherence and quality of life.
The KONFIDENT-S European interim analysis further confirmed that EKTERLY is effective and well-tolerated across a diverse population, including adolescents, supporting its broad applicability in clinical practice.
Patient-Centered Impact
Beyond the clinical data, the DGAKI presentations highlighted the real-world implications of EKTERLY for patients with HAE. By enabling earlier treatment, an oral therapy can reduce both the physical and psychological burden of attacks. Patients gain greater autonomy, confidence, and flexibility in managing their condition, improving overall quality of life.
Survey data from German patients emphasize the urgency of such innovations: delays in treatment were linked to prolonged attack duration, increased pain, and greater disruption to daily life. EKTERLY’s oral formulation has the potential to overcome these obstacles, allowing patients to treat attacks promptly, avoid severe outcomes, and reduce reliance on healthcare facilities for administration.
Looking Ahead
KalVista Pharmaceuticals is actively preparing for the rollout of EKTERLY in Europe, with Germany serving as the initial launch market in late 2025. Subsequent launches across other European countries are planned throughout 2026, broadening access to this transformative therapy. KalVista remains committed to ongoing education, outreach, and patient support initiatives to ensure optimal utilization of EKTERLY and improved outcomes for individuals living with HAE.
The data from the KONFIDENT and KONFIDENT-S trials, along with real-world survey insights, underscore the transformative potential of EKTERLY (sebetralstat) as the first oral on-demand therapy for HAE. By addressing the limitations of injectable therapies and enabling rapid, effective treatment of acute attacks, EKTERLY represents a significant advance in patient-centered care. Its approval in the European Union marks an important milestone for HAE management, providing patients and healthcare providers with a convenient, reliable, and life-improving alternative to traditional injectable therapies.
With EKTERLY, KalVista Pharmaceuticals is poised to redefine the standard of care for hereditary angioedema in Europe, offering patients unprecedented autonomy, faster relief, and the potential for better long-term outcomes in managing this rare and challenging disease.
