[Edaily Reporter KIM JI-WAN ] #Onconic Therapeutics Inc.’s gastroesophageal reflux disease (GERD) treatment “Zacubo” has demonstrated, through clinical data, the competitiveness of its orally disintegrating tablet formulation, which can be taken without water. The drug showed equivalent drug exposure when dissolved in the mouth compared to when conventional tablets were swallowed with water. This allows for a simpler administration method while maintaining the same level of drug delivery to the body.

According to a recent company announcement, a study comparing the pharmacokinetic characteristics and safety of Jacubo orally disintegrating tablets and conventional tablets was published on the 16th in the international academic journal *Pharmacology Research & Perspectives* (PR&P).

Zacubo is a potassium-competitive acid blocker (P-CAB) containing zastaprazan citrate as its active ingredient. It treats gastroesophageal reflux disease by inhibiting gastric acid secretion, and the standard tablet was launched in October 2024.

Equivalent Even Without Water… Results Showed ‘95%·108%’

The key focus of this study was to confirm whether the drug is delivered to the body at a level equivalent to that of conventional tablets

even when taken without water. The results showed

that the drug met bioequivalence criteria whether taken with or without water.

The study involved 54 healthy adults. Participants took 20 mg of Zastaprazan in three different ways: swallowing a standard tablet with water, or taking an oral disintegrating tablet of the same dose with or without water. Of these, 51 completed the entire trial schedule.

By having the same participants try each of the three administration methods in sequence, the researchers minimized the impact of individual physiological differences on the results. The research team administered the medication on an empty stomach and tracked drug concentrations in the blood for up to 36 hours.

There were two comparison criteria: “peak plasma concentration,” which is the highest level reached by the drug in the blood, and “total drug exposure,” which summarizes drug concentrations over time. The study examined both how high the drug concentration reached in the blood and the overall level of exposure.

The results are easier to understand when compared to conventional tablets, with their values set as 100. When the orally disintegrating tablet was taken without water, the peak plasma concentration was 95.05 and the total drug exposure was 108.00. When taken with water, these values were 90.85 and 101.88, respectively. This means the results fell within the 80–125% range required for bioequivalence.

An Onconic official stated, “This study confirmed that the Jacubo orally disintegrating tablet meets the criteria for bioequivalence with the existing standard tablet under both conditions—when taken with or without water.”

First Approval in India

, Phase 3 Trials for

Injectable Formulation in China… Simultaneous Expansion of “

Dosage

Forms and Indications” Overseas

Zacubo’s growth is expanding overseas.

In India

, the company secured its

first

overseas marketing authorization.

In China

, the approval review for the oral formulation and Phase 3 clinical trials

for the injectable formulation

are proceeding

simultaneously

. The company is expanding not only into new markets but also in terms of dosage forms and therapeutic indications.

The first overseas approval came from India. In August, Onconic Therapeutics Inc. received approval from India’s Central Drugs Standard Control Organization (CDSCO) to manufacture and sell Jacubo locally as a treatment for erosive gastroesophageal reflux disease (GERD). Following the announcement in June of the successful completion of a local Phase 3 clinical trial and the submission of a marketing authorization application, the company has now cleared the final hurdle for commercialization. Its local partner is currently preparing for the product’s launch, including production and distribution.

In China, the scope of development is even broader. Partner company Livzone Pharmaceuticals applied for marketing authorization for the oral formulation of Zastaprazan for erosive gastroesophageal reflux disease (GERD) in August of last year. In May of this year, the company entered Phase 3 clinical trials for Helicobacter pylori eradication therapy, and in September, it administered the first dose in a Phase 3 clinical trial of an injectable formulation for patients with bleeding peptic ulcers.

This strategy involves expanding the scope of application from oral medications for reflux disease to combination therapy for eradicating Helicobacter pylori and injectable formulations for patients with bleeding. Onconic has claimed an additional $1 million (1.3 billion won) in milestone payments based on progress in the development of the injectable formulation.

According to market research firm IQVIA, the global market for gastroesophageal reflux disease (GERD) treatments is valued at approximately 40 trillion won, with the Chinese market estimated to be worth between 4 trillion and 6 trillion won. Livzone is a leading local pharmaceutical company in the gastrointestinal sector, generating annual sales of over 600 billion won in gastrointestinal treatments, and possesses a strong sales and distribution network in China.

The company has also laid the groundwork for expansion into Southeast Asia and Latin America. Last June, it signed a licensing and supply agreement with Indonesian pharmaceutical company Dexa Medica. Dexa Medica will handle local regulatory approvals and sales, while Onconic will supply the finished products.

That same month, the company completed its application for product approval in Mexico. The agreement signed with its Latin American partner, Laboratorio Sanper, covers 19 countries, including Mexico. Commercialization efforts are taking shape across regions, with approval already secured in India and approval processes underway in China and Mexico.
95

% Healing Rate in 4 Weeks… Injectable Form Seeks to Differentiate Itself with “30 Minutes a Day” Administration

Zacubo has demonstrated its therapeutic competitiveness in clinical trials comparing it to existing proton pump inhibitors. A study involving 300 patients with erosive esophagitis—a condition characterized by lesions on the esophageal mucosa—compared the efficacy of 20 mg of Zacubo with that of the existing drug, 40 mg of esomeprazole.

After four weeks of treatment, the rate of patients whose lesions had healed was 95.14% for Jacubo and 87.68% for esomeprazole. On a per-100-patient basis, this means that the esophageal mucosa healed in approximately 95 and 88 patients, respectively.

An injectable formulation currently under development in China has shown potential for reducing administration time. Local partner Livzone conducted a Phase 2 clinical trial involving 109 patients who had experienced bleeding from gastric or duodenal ulcers and underwent endoscopic hemostasis.

In this trial, the comparator drug, esomeprazole, was administered via continuous infusion over 72 hours. In contrast, zastaprazan was administered once daily for 30 minutes over three days. This significantly reduced the time patients had to remain connected to an IV for drug delivery.

Endoscopy was also used to confirm whether bleeding recurred within 72 hours after treatment. The rebleeding rate was 0% in the 40 mg Zastaprazan group, 2.9% in the 20 mg group, and 3.0% in the comparator group. These results suggest that equivalent therapeutic efficacy can be expected even with a shorter treatment duration.

In this way, Jacubo combines treatment outcomes comparable to existing drugs with improved convenience. By developing an injectable formulation to complement its orally disintegrating tablets—which dissolve in the mouth without water—the company is expanding the range of options available to suit patients’ conditions and treatment environments.

An Onconic official stated, “As country-specific approvals and commercialization proceed, there is a possibility of receiving additional milestone payments on top of existing revenue, and once local sales begin, we can also expect royalty revenue linked to sales performance.”