What is the recommended dosing regimen for vonoprazan (20 mg) for gastro‑oesophageal reflux disease, H. pylori eradication, and in patients with hepatic impairment?

Vonoprazan 20 mg Dosing Recommendations

Vonoprazan 20 mg once daily is the standard dose for healing erosive esophagitis and H. pylori eradication, with specific dose adjustments required for renal and hepatic impairment. 1

Dosing by Indication

Gastroesophageal Reflux Disease (GERD)

Healing of Erosive Esophagitis:

• Standard dose: 20 mg once daily for 8 weeks 1
• Can be taken with or without food 1
• Swallow whole; do not crush or chew 1

Maintenance of Healed Erosive Esophagitis:

• 10 mg once daily for up to 6 months 1
• This lower maintenance dose is particularly appropriate for LA grade A/B erosive esophagitis 2
• For severe erosive esophagitis (LA grade C/D), vonoprazan demonstrates superior maintenance compared to PPIs, with recurrence rates of 5-13% versus 39% for lansoprazole 2

Non-Erosive GERD:

• 10 mg once daily for 4 weeks 1
• Not recommended as first-line therapy due to cost and limited long-term safety data 2

H. pylori Eradication

Triple Therapy (Preferred):

• Vonoprazan 20 mg + amoxicillin 1,000 mg + clarithromycin 500 mg, all twice daily for 14 days 1
• Doses given in morning and evening, 12 hours apart 1
• This regimen achieves 92% eradication rates versus 80% with PPI-based therapy 2
• Particularly superior for clarithromycin-resistant strains (66-70% vs 32% with PPIs) 2

Dual Therapy (Alternative):

• Vonoprazan 20 mg twice daily + amoxicillin 1,000 mg three times daily for 14 days 1
• Amoxicillin given morning, mid-day, and evening 1
• Seven-day dual therapy (vonoprazan 20 mg + amoxicillin 750 mg twice daily) showed 85% eradication in Japanese studies 2

Key Clinical Point: The 2024 AGA guidelines strongly recommend P-CABs over PPIs for H. pylori eradication in most patients, representing one of the few indications where vonoprazan should be preferred first-line therapy 2

Dose Adjustments for Renal Impairment

Healing of Erosive Esophagitis:

• eGFR ≥30 mL/min: 20 mg once daily (standard dose) 1
• eGFR <30 mL/min: 10 mg once daily (reduced dose) 1

Maintenance Therapy or Non-Erosive GERD:

• No dose adjustment needed regardless of renal function 1

H. pylori Eradication:

• eGFR ≥30 mL/min: 20 mg twice daily (standard dose) 1
• eGFR <30 mL/min: Use is NOT recommended 1

Dose Adjustments for Hepatic Impairment

Healing of Erosive Esophagitis:

• Child-Pugh Class A: 20 mg once daily (standard dose) 1
• Child-Pugh Class B: 10 mg once daily (reduced dose) 1
• Child-Pugh Class C: 10 mg once daily (reduced dose) 1

Maintenance Therapy or Non-Erosive GERD:

• No dose adjustment needed for any degree of hepatic impairment 1

H. pylori Eradication:

• Child-Pugh Class A: 20 mg twice daily (standard dose) 1
• Child-Pugh Class B: Use is NOT recommended 1
• Child-Pugh Class C: Use is NOT recommended 1

Pharmacokinetic Rationale

The dose adjustments are based on significant exposure increases in impaired patients. Severe hepatic impairment increases vonoprazan exposure 2.6-fold, and severe renal impairment increases it 2.4-fold 3. Despite these increases, protein binding remains unchanged 3.

Vonoprazan's longer half-life (approximately 7.7 hours) compared to PPIs (1-2 hours) allows for sustained acid suppression over 24 hours, making once-daily dosing effective 2, 3. The drug achieves pH >4 for 89.7% of 24 hours with 20 mg once daily and 98.1% with twice-daily dosing 4.

Missed Dose Instructions

For GERD (healing or maintenance):

• If <12 hours since missed dose: take as soon as possible 1
• If >12 hours: skip and resume regular schedule 1

For H. pylori eradication:

• If <4 hours since missed dose: take as soon as possible 1
• If >4 hours: skip and resume regular schedule 1
• Continue until full 14-day course completed 1

Clinical Caveats

Cost considerations: Vonoprazan is significantly more expensive than PPIs in the United States, which limits its first-line use except for H. pylori eradication and severe erosive esophagitis refractory to PPIs 2.

Timing flexibility: Unlike PPIs, vonoprazan does not require pre-meal dosing due to acid stability and longer half-life 2.

CYP2C19 independence: Genetic polymorphisms have minimal clinical impact (15-29% exposure variation), unlike PPIs 3.