HK Innoen's New Drug "Kepab" Succeeds in U.S. Phase 3 Trial... Eyes FDA Approval

HK Innoen has secured positive results in a U.S. Phase 3 maintenance therapy clinical trial for its new gastroesophageal reflux disease (GERD) drug, Kepab (active ingredient: Tegoprazan). The company has passed the final hurdle for a New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA), and is expected to submit the application within this year.

The product Kepab (active ingredient: Tegoprazan), a new drug for gastroesophageal reflux disease by HK Innoen, which secured positive results in a Phase 3 clinical trial in the United States. Photo provided by HK Innoen

HK Innoen announced on August 8 that its U.S. partner, Sebela Pharmaceuticals, released the topline results of the U.S. Phase 3 clinical trial (TRIUMpH) evaluating maintenance therapy with Kepab (hereafter "Tegoprazan") after treatment of erosive esophagitis (EE) in GERD patients, on August 7 (local time).

This clinical trial was conducted by Braintree, a gastrointestinal medicine specialist subsidiary of Sebela, which entered into a technology transfer agreement with HK Innoen in 2021.

The trial was conducted on patients with fully healed erosive esophagitis (EE) after up to 8 weeks of initial treatment. Patients were randomly assigned to receive either Tegoprazan 100 mg, Tegoprazan 50 mg (both P-CAB class), or lansoprazole 15 mg (a PPI), and then underwent maintenance therapy for 24 weeks.

For the primary endpoint of maintenance of therapeutic effect (remission maintenance rate) over 24 weeks, all Tegoprazan dose groups demonstrated not only non-inferiority but also statistical superiority compared to the lansoprazole group across all patient groups (LA grades A?D).

Notably, in patients with moderate to severe esophagitis (LA grades C?D), all Tegoprazan dose groups showed significant improvement over the lansoprazole group, and the Tegoprazan 100 mg group demonstrated statistical superiority.

Additionally, both Tegoprazan doses confirmed non-inferiority to lansoprazole in the proportion of days without heartburn over 24 hours.

Based on these clinical results, Sebela plans to submit a U.S. FDA NDA for indications in erosive esophagitis and non-erosive GERD in the fourth quarter of this year. The results of the TRIUMpH Phase 3 study are scheduled to be presented in major academic journals and at leading international gastroenterology conferences.

Alan Cook, CEO of Sebela Pharmaceuticals, stated, "Tegoprazan demonstrated excellent maintenance effects in the entire patient group, including those with moderate to severe erosive esophagitis, and showed sustained symptom control for heartburn." He added, "With a safety profile similar to existing therapies, Tegoprazan could become an innovative treatment option that meets the unmet needs of U.S. patients."

Prakash Gyawali, director of the Center for Gastrointestinal Functional and Motility Disorders at Washington University and a leading expert in the field, commented, "These maintenance therapy data demonstrate the clinical value of Tegoprazan in GERD, especially in patients with moderate to severe erosive esophagitis. This supports Tegoprazan as an important new drug that can help patients achieve healing and symptom relief."

Kwack Dalwon, CEO of HK Innoen, said, "We are pleased that Kepab has successfully completed maintenance therapy trials following Phase 3 studies for erosive and non-erosive GERD. Entry into the U.S., the world's largest pharmaceutical market, is now within reach. Together with our partner, we will do our utmost to ensure a smooth U.S. FDA application process."

Meanwhile, in this study, the incidence of individual adverse events was below 3%, and most were mild and transient. Serious adverse events occurred in less than 1% of cases, and the incidence rates of adverse events were similar among the Tegoprazan, PPI, and placebo groups. Mean serum gastrin levels remained within the normal range (0?180 pg/ml) throughout the maintenance therapy period.

Previously, in April, Sebela announced that Tegoprazan (Korean product name Kepab) met both primary and secondary endpoints in Phase 3 clinical trials for erosive and non-erosive GERD.

According to the announcement, Tegoprazan showed superior healing effects compared to PPI (lansoprazole) in 2-week and 8-week treatments for erosive esophagitis of all grades (LA A?D). In non-erosive GERD, Tegoprazan also demonstrated significant improvements over placebo in acid reflux and in both 24-hour and nighttime heartburn symptoms.

Tegoprazan is the active ingredient of Kepab, the 30th new drug developed in South Korea by HK Innoen. As a P-CAB class new drug for GERD, it was launched domestically in March 2019 and recorded cumulative prescription sales of 810.1 billion KRW through the first half of 2025.

With features such as rapid onset of action and proven safety for long-term use over six months, Kepab ranks first in domestic outpatient prescriptions for peptic ulcer medications. HK Innoen has signed technology or finished product export agreements with 54 countries including South Korea, and the product has been launched in 17 of them.