HK inno.N’s K-CAB tops standard acid treatment in US reflux trials, FDA filing next

HK inno.N’s K tegoprazan (marketed as K-CAB in Korea), a fast-acting acid blocker from the P-CAB class, beat lansoprazole, a widely used PPI, in two late-stage U.S. trials for acid reflux, the Korean drugmaker and U.S. partner Sebela Pharmaceuticals said Thursday. An FDA filing is expected later this year.

In phase 3 trials of more than 2,000 patients with GERD, a condition where stomach acid repeatedly backs up into the esophagus, tegoprazan hit all primary and secondary endpoints in both erosive esophagitis (EE) -- marked by visible damage -- and non-erosive reflux disease (NERD), where symptoms like heartburn and regurgitation occur without clear injury.

In the EE trial, tegoprazan showed superior healing at both weeks two and eight versus lansoprazole, including in patients with severe cases classified as LA Grades C and D, which indicate large or circumferential erosions. In NERD, the drug delivered full symptom relief, wiping out overnight heartburn and regurgitation -- where older therapies often fall short.

“This includes superior EE healing for all patients over lansoprazole at weeks 2 and 8 of treatment,” said Alan Cooke, CEO of Sebela, which licensed the drug from HK inno.N in 2021 and ran the studies through its gastrointestinal unit, Braintree Laboratories.

Tegoprazan belongs to a newer drug class called potassium-competitive acid blockers (P-CABs), designed to block acid faster and more consistently than proton pump inhibitors (PPIs), which act later in the acid production process. A prior U.S. study showed tegoprazan raised stomach pH above 4 in 45 minutes and worked regardless of food intake.

Felice Schnoll-Sussman, professor of clinical medicine at Weill Cornell, said the EE data “proves that the P-CAB class can outperform PPIs and suggests that tegoprazan may offer advantages over other agents.”

Prateek Sharma, president of the American Society of Gastrointestinal Endoscopy, added that regurgitation, often overlooked in prior GERD studies, was improved. “Previous studies on medical therapies have not been able to show or measure reduction in regurgitation like the P-CAB tegoprazan,” he said.

Safety results were in line with expectations. Fewer than 3 percent of patients experienced drug-related adverse events, most of which were mild and temporary. Serious events occurred in under 2 percent of patients across all groups, with no significant differences between tegoprazan, lansoprazole, and placebo. Serum gastrin -- a hormone that can rise when acid is blocked -- remained within the normal range of 0 to 180 pg/ml in all treatment arms.

A maintenance trial for EE is expected to wrap by the third quarter of 2025, with a new drug application to the FDA planned for the fourth quarter covering both indications, according to Thursday’s release.

K-CAB, first approved in Korea in 2019, is HK inno.N’s flagship product and the country’s 30th homegrown novel drug. It has generated over 705.4 billion won ($494 million) in domestic sales and has been licensed or exported to 48 countries, with launches in 15 to date.