Medicosnext
Dr. Sandeep Raj Kunwar
He is a senior gastroenterologist and interventional endoscopist with over a decade of experience in managing complex gastrointestinal and hepatobiliary disorders. He currently leads the Digestive Disease Centre at Norvic International Hospital and serves as Scientific Chair of the Nepalese Society of Gastroenterologists. He has extensive training from King Edward Medical University and Mayo Hospital, Lahore, and has performed more than 25,000 diagnostic and therapeutic endoscopic procedures, including ERCP and EUS. He is recognized as a pioneer in therapeutic endoscopic ultrasound (EUS) in Nepal. Dr. Kunwar has a special interest in pancreatobiliary diseases, gastrointestinal bleeding, and advanced endoscopy. He has actively contributed to academic medicine as a researcher and international faculty speaker. His work includes multiple award winning presentations, publications, and participation in global conferences across Asia and Europe. He is affiliated with major international societies and has played a key role in advancing gastroenterology practice, education, and endoscopic innovation in Nepal.
Vonoprazan is a new class of acid-suppressing medication known as a potassium-competitive acid blocker (P-CAB). Unlike traditional proton pump inhibitors (PPIs), it acts directly on the stomach’s acid-producing pumps without requiring prior activation. It provides rapid, sustained acid suppression that remains effective throughout the night.
This rapid action distinguishes vonoprazan from conventional PPIs such as Omeprazole, Pantoprazole, Esomeprazole, and Rabeprazole, which often take several days to reach full effect and are highly dependent on meal timing. Vonoprazan works by competing with potassium on the proton pump to inhibit gastric acid secretion. It works from the first dose and can be taken regardless of meals, offering stronger and more consistent results by competing with potassium to block the acid pump.
International guidelines and recent global consensus statements support its use for gastroesophageal reflux disease (GERD), peptic ulcer disease, and Helicobacter pylori eradication. It is particularly effective for patients who do not respond well to PPIs or those with persistent nocturnal symptoms. Furthermore, evidence suggests higher H. pylori eradication rates when using vonoprazan-based regimens compared to traditional therapies.
The clinical advantages include faster symptom relief, superior healing rates, and effectiveness regardless of genetic differences in PPI metabolism. These benefits are especially relevant in busy clinical practices where predictable outcomes are essential. Unlike PPIs, P-CABs bind reversibly to the receptor, are acid-stable, and are not affected by the presence of food. It is worth noting that both vonoprazan and PPIs block the final step in acid production or the HK-ATPase.While PPIs work through irreversible covalent binding to the alpha subunit of HK-ATPase, vonoprazan selectively and reversibly competes with luminal potassium ions required for hydrogen exchange. Vonoprazan is acid stable and does not require an acidic environment for activation unlike PPIs nor does it require enteric coating to protect from gastric degradation.
While current evidence suggests a safety profile similar to PPIs, long-term safety data is still evolving. As with any potent acid suppression, clinicians should remain mindful of potential concerns related to prolonged use, such as micronutrient deficiencies or infections. Common adverse effects associated with vonoprazan include nasopharyngitis, diarrhea, constipation, flatulence, dyspepsia, headache, and abdominal pain. Vonoprazan is metabolized via cytochrome P450 (CYP450) through CYP3A4/5, CYP2B6, CYP2C19, CYP2C9, and CYP2D6 subtypes and none of its metabolites are pharmacologically active.
First developed in Japan and approved in 2015, vonoprazan gained U.S. approval in 2023 and was approved in India in 2024. It is expected to be introduced in Nepal soon, with leading pharmaceutical companies preparing for local availability.
From the perspective of a tertiary care center like Norvic International Hospital, the clinical landscape in Nepal presents unique challenges in managing acid related disorders. We encounter a high burden of Helicobacter pylori infection, widespread empirical use of conventional proton pump inhibitors such as Omeprazole, Pantoprazole, Esomeprazole, and Rabeprazole, and frequent issues with treatment adherence and follow up. Dietary patterns, including spicy and fermented foods, along with easy over the counter access to medications, further complicate disease control. In this setting, the introduction of Vonoprazan offers a practical advantage due to its rapid, consistent acid suppression and independence from meal timing. From a clinician’s standpoint, this translates into more predictable outcomes, particularly in H. pylori eradication and refractory GERD, where conventional PPIs often show variable response. Importantly, with emerging local availability, the cost is expected to be comparable to conventional PPIs, which may facilitate wider adoption in routine clinical practice. While accessibility and long term data will continue to guide its use, Vonoprazan has the potential to address several real world gaps in the Nepali healthcare context and improve overall treatment success rates.
In my view, vonoprazan is not merely an alternative to PPIs but a more reliable acid suppressor in selected patients, particularly those with PPI failure, requiring H. pylori eradication, and intractable reflux disease, an evolving burden in our community which has been posing challenges in clinical treatment. Its introduction into Nepalese clinical practice has the potential to significantly improve treatment outcomes while maintaining practicality in everyday clinical settings.
