Phase 3 trial of sebetralstat for young HAE patients is fully enrolled
KONFIDENT-KID trial includes more children due to 'overwhelming interest'
A Phase 3 clinical trial testing sebetralstat as an on-demand treatment for swelling attacks in children with hereditary angioedema (HAE) has completed enrollment a year ahead of schedule.
The trial’s initial target enrollment was surpassed in less than seven months, according to KalVista Pharmaceuticals, which is developing sebetralstat.
Originally enrolling 24 children, the KONFIDENT-KID trial (NCT06467084) was expanded due to high demand to include 36 children, ages 2 to 11, across seven countries in North America, Europe, and Asia.
“We’re proud to share that we achieved target enrollment in our KONFIDENT-KID trial a full year ahead of schedule and expanded the trial size due to overwhelming interest,” Ben Palleiko, KalVista’s CEO, said in a company press release. “The high level of participation from families living with HAE underscores the significant need for an oral treatment option for this population.”
US decision expected in June on sebetralstat for patients 12 and older
Initial trial results are expected by year’s end and could support a supplemental new drug application to expand sebetralstat’s potential approval to young children with HAE. An application seeking the treatment’s approval for patients 12 and older is currently under review by the U.S. Food and Drug Administration, with a decision expected by June 17.
“Even with this larger trial size, we anticipate that initial results will be shared later this year, with [a supplemental new drug application] expected to be filed by mid-2026,” Palleiko said.
HAE is characterized by the excessive production of bradykinin, a signaling molecule that causes blood vessels to widen and to become more permeable, causing fluid to leak out and build up in the deeper layers of the skin or mucus membranes, leading to swelling attacks. In some cases, swelling attacks can affect the airways and become life-threatening.
Sebetralstat is an oral therapy designed to block the activity of kallikrein, an enzyme involved in bradykinin production. When administered, it is expected to reduce bradykinin levels, bringing swelling under control during an attack.
Among the on-demand treatments for HAE attacks, only Berinert (human C1 esterase inhibitor) is approved in the U.S. for swelling attacks in children, and is given by an intravenous (into-the-vein) injection. If approved, sebetralstat would become the first oral on-demand therapy in the U.S. to be available to treat swelling attacks in young children and the second on-demand therapy overall for this specific patient population.
KONFIDENT-KID will test 3 doses of oral sebetralstat
Launched last year, KONFIDENT-KID will assess sebetralstat’s safety, pharmacological properties, and efficacy for up to one year in children with HAE. All the children will be treated with one of three doses (75, 150, or 300 mg) of sebetralstat, given in the form of tablets that can dissolve on the tongue.
The trial’s main goal is to assess the treatment’s safety, by measuring the proportion of children experiencing side effects. Secondary goals include assessing the time to symptom relief and the time to attack resolution.
In the Phase 3 KONFIDENT clinical trial (NCT05259917) and the ongoing KONFIDENT-S extension study (NCT05505916), enrolling HAE patients 12 and older, most participants started experiencing symptom relief in less than two hours, with complete attack resolution occurring within a day.
These results supported the company’s applications for sebetralstat to regulatory authorities in the U.S., European Union, Japan, and other countries.
About the Author
