Onconic Therapeutics, a Jeil Pharmaceutical subsidiary, has scored a new approval for its oral P-CAB therapy Jaqbo (zastaprazan citrate), adding gastric ulcer to the label just over a year after the drug’s commercial debut in erosive GERD, a type of acid reflux that damages the esophagus.

The green light from the Ministry of Food and Drug Safety (MFDS) follows a successful phase 3 study completed in January and makes Jaqbo the second P-CAB drug in Korea cleared for gastric ulcer, trailing only HK inno.N’s K-CAB (tegoprazan), which picked up the same indication in 2021.

Approved as Korea’s 37th locally developed novel drug, Jaqbo launched in October 2024 and has already racked up more than 10 billion won ($7.3 million) in cumulative prescriptions, according to data from UBIST. 

First-quarter 2025 sales more than doubled from the previous quarter, reaching 6.7 billion won, as the drug gained traction in major hospitals including Seoul National University Hospital, Samsung Medical Center, and Severance Hospital.

In a pivotal phase 3 study, 329 gastric ulcer patients were randomized across 39 Korean sites. Jaqbo (20 mg daily) delivered a 100 percent healing rate at week 8 in the per-protocol set, meeting the non-inferiority bar against lansoprazole (30 mg), Onconic said. The two therapies showed comparable safety profiles, the company added.

At week 4, patients taking Jaqbo also reported significant improvements in anxiety and depression scores. No additional clinical data were disclosed in Monday’s release.

The new data builds on what’s already a fast-moving launch. Onconic is also running trials to expand into NSAID-induced ulcer prevention and is developing an orally disintegrating tablet formulation aimed at elderly GERD patients with swallowing difficulties.

Meanwhile, HK inno.N’s K-CAB remains Jaqbo’s key domestic rival. In its own phase 3 gastric ulcer trial, K-CAB showed eight-week healing rates of 95 percent or higher across both 50 mg and 100 mg doses, with efficacy and safety matching lansoprazole.