Presentations at ISPOR and the Eastern Allergy Conference highlight substantial treatment burden, caregiver anxiety, delayed or untreated HAE attacks, and high healthcare resource utilization among children aged 2–11 living with HAE

KalVista Pharmaceuticals, Inc. (NASDAQ:KALV) today announced new data highlighting the burden of injectable on-demand treatment in children aged 2–11 with hereditary angioedema (HAE) presented at ISPOR 2026 and the Eastern Allergy Conference (EAC).

"These data highlight the significant unmet needs that exist for children living with HAE and the families who care for them," said Ben Palleiko, Chief Executive Officer of KalVista. "Currently, the only FDA-approved on-demand treatment for children ages 2–11 requires intravenous administration, which can place a considerable burden on both children and caregivers during already stressful attacks. Across real-world treatment patterns, healthcare resource utilization, and caregiver experiences, these findings reinforce the need for new treatment options that are easy to use and support early, consistent treatment of attacks. As the first and only oral on-demand treatment for HAE, EKTERLY^® has the potential to meaningfully improve the treatment experience for this pediatric population and serve as a family-wide solution across generations."

On-Demand Treatments for Hereditary Angioedema and Healthcare Resource Utilization in Pediatric (2–11 Years) Patients: A US Claims Database Analysis was presented at ISPOR by Alice Wang, Senior Director, Global Health Economics and Value Demonstration, KalVista Pharmaceuticals.

Real-world claims data showed that while about two thirds of children aged 2–11 were prescribed IV pdC1INH—the only FDA-approved on-demand HAE treatment for this population—the majority of treatments utilized were off-label (primarily icatibant), suggesting families and providers may be seeking less invasive treatment options.
Although the mean on-demand dosing rate was 0.43 per patient per month, the rate for pdC1INH was far less (0.28) than that of icatibant (0.72).
Healthcare resource utilization was substantial with 47% of patients requiring emergency room care and 17% utilizing home-health services.

Burden of Injectable On-Demand Treatment for Hereditary Angioedema Attacks in Children will be presented at EAC by Timothy Craig, DO, Professor, Departments of Medicine and Pediatrics, Division of Pulmonary, Allergy and Critical Care Medicine, Penn State Health.

A caregiver survey found that nearly half of children did not receive on-demand treatment for their most recent HAE attack.
Among children who did treat their last attack, 93.7% experienced anxiety about using injectable on-demand treatment, with 68.8% reporting extreme anxiety.
Among the most common reasons for not treating or feeling anxious about treatment were fear of needles and anticipated burning, stinging or pain from the injection.
Seventy-five percent experienced a side effect from treatment, most commonly pain from the needle and burning, stinging or pain while injecting treatment.

Caregiver Burden Associated with Injectable On-Demand Treatment of Hereditary Angioedema Attacks in Children will be presented at EAC by H. Henry Li, MD, Institute for Asthma and Allergy.

The same caregiver survey found that during their child's last HAE attack, 43% occurred outside the home and 37% occurred while they were not with their child.
63% of caregivers had difficulty administering treatment and 31% took their child to a hospital or emergency center for treatment.
Caregiver anxiety was high, with 90% of caregivers reporting anxiety about deciding to treat, including 60% who felt extremely anxious.
Mean time to treatment was 2.8 hours, with only 31% of caregivers treating in less than one hour.
The majority of caregivers reported that the most important factor that could make on-demand treatment better for their child would be an oral therapy.

"Across real-world datasets, we consistently see a substantial treatment burden for young children with HAE and their caregivers, often resulting in treatment avoidance or long delays in on-demand treatment. We also observe high rates of anxiety among children and caregivers related to injectable treatments. We believe these challenges drive higher-than-expected healthcare resource utilization, including emergency room visits and home healthcare support for treatment administration," said Paul Audhya, MD, MBA, Chief Medical Officer of KalVista. "It is therefore not surprising that caregivers identify oral therapy as the most important factor that could improve on-demand treatment for their child. Ultimately, these presentations reinforce the value of an oral on-demand therapy that can be taken anytime, anywhere, without the challenges associated with injectables, and may help enable guideline-aligned care for the first time."

KalVista continues to execute the KONFIDENT-KID trial—the fastest-enrolling pediatric HAE trial conducted to date—and intends to submit a new drug application for sebetralstat in children aged 2–11 in the third quarter of 2026.

A link to the presentation is available on the KalVista website under Publications.

About Hereditary Angioedema

Hereditary angioedema (HAE) is a rare genetic disease resulting in deficiency or dysfunction in the C1 esterase inhibitor (C1INH) protein and subsequent uncontrolled activation of the kallikrein-kinin system. People living with HAE experience painful and debilitating attacks of tissue swelling in various locations of the body that can be life-threatening depending on the area affected. Treatment guidelines recommend treating attacks as early as possible to prevent progression of swelling and shorten the time to attack resolution, and to consider treatment for all attacks, regardless of anatomic location or severity.

About KONFIDENT-KID

KONFIDENT-KID is an open label clinical trial of sebetralstat for on-demand treatment of HAE attacks in pediatric patients. Originally designed to enroll 24 pediatric patients, the trial was met with high demand and will ultimately enroll approximately 36 children aged 2-11 years across seven countries in North America, Europe and Asia. KONFIDENT-KID will collect safety, pharmacokinetic and efficacy data for each patient for up to one year and features a proprietary pediatric oral disintegrating tablet (ODT) formulation of sebetralstat. If approved, sebetralstat would be the first oral on-demand therapy for this age group, and only the second FDA-approved on-demand therapy of any type for this population.

About EKTERLY^® (sebetralstat)

EKTERLY (sebetralstat) is a novel plasma kallikrein inhibitor approved in the United States, European Union, United Kingdom, Switzerland, Australia, Singapore and Japan for the treatment of acute attacks of hereditary angioedema (HAE) in people 12 years of age and older. EKTERLY is the first and only oral on-demand treatment for HAE, offering efficacious and safe treatment of attacks without the burden of injections. With a US regulatory filing planned for 2026 to expand use to children aged 2–11, and additional filings anticipated in key global markets, EKTERLY has the potential to become the foundational therapy for HAE management worldwide. For more information, including the full US Prescribing Information, visit EKTERLY.com.

About KalVista Pharmaceuticals, Inc.

KalVista is a global pharmaceutical company dedicated to delivering life-changing oral therapies for individuals affected by rare diseases with significant unmet needs. The KalVista team discovered and developed EKTERLY^®—the first and only oral on-demand treatment for hereditary angioedema (HAE)—and continues to work closely with the global HAE community to improve treatment and care for this disease around the world. For more information about KalVista, please visit www.kalvista.com and follow us on LinkedIn, X, Facebook and Instagram.

Forward-Looking Statements

This press release contains "forward-looking" statements within the meaning of the safe harbor provisions of the U.S. Private Securities Litigation Reform Act of 1995. Forward-looking statements can be identified by words such as: "anticipate," "intend," "plan," "goal," "seek," "believe," "project," "estimate," "expect," "position," "strategy," "future," "likely," "may," "should," "will" and similar references to future periods. These statements are subject to numerous risks and uncertainties that could cause actual results to differ materially from what we expect. Examples of forward-looking statements include, among others, information relating to our business and business plans, the success of our efforts to commercialize EKTERLY^® (sebetralstat), our ability to successfully obtain foreign regulatory approvals for sebetralstat, our expectations about the safety and efficacy of sebetralstat, the timing of clinical trials and their results, our ability to commence clinical studies or complete ongoing clinical studies, including our KONFIDENT-KID trial, and the ability of EKTERLY to treat HAE. Further information on potential risk factors that could affect our business and financial results are detailed in our filings with the Securities and Exchange Commission, including in our transition report on Form 10-KT for the transition period from May 1, 2025 to December 31, 2025, our quarterly reports on Form 10-Q, and our other reports that we may make from time to time with the Securities and Exchange Commission. We undertake no obligation to publicly update any forward-looking statement, whether written or oral, that may be made from time to time, whether as a result of new information, future developments or otherwise.

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Ryan Baker

Head, Investor Relations

(617) 771-5001

ryan.baker@kalvista.com

Molly Cameron

Senior Director, Corporate Affairs

(978) 339-3378

molly.cameron@kalvista.com

KalVista Pharmaceuticals Presents New Data Highlighting the Burden of Injectable On-Demand Treatment in Young Children with Hereditary Angioedema