Vonoprazan-based regimen shows treatment potential against H. pylori

A 14-day quadruple therapeutic regimen containing vonoprazan – a first-in-class potassium-competitive acid blocker (P-CAB) with reportedly stronger acid inhibition than proton pump inhibitors – provided an excellent cure rate for Helicobacter pylori (H. pylori) infection in patients with high clarithromycin and quinolone resistance regardless of CYP3A4/5 genotypic polymorphism, according to the prospective VQ-HP trial presented at APDW 2021.

H. pylori infection is an important risk factor for gastric cancer. [Gastric Cancer 2019;22:435-445; Gut 2018;67:2092-2096] Moreover, despite its declining prevalence, H. pylori reinfection rates remain high in certain regions. [Helicobacter 2016;21:3-7] “[As such,] H. pylori eradication [is important to] reduce the progression of precancerous lesions of gastric cancer,” said Dr Nuttapat Tungtrongchitr from the Thammasat University Hospital, Pathum Thani, Thailand, who presented the findings.

The Maastricht V/Florence Consensus Report recommends bismuth-containing quadruple regimens for managing H. pylori infection in areas with high clarithromycin and metronidazole resistance. [Gut 2017;66:6-30]

In a Japanese study, a vonoprazan-amoxicillin-based regimen demonstrated acceptable H. pylori eradication rates – triple (with clarithromycin) bested the dual regimen in terms of eradicating susceptible strains (95 percent vs 86 percent), while resistant strains responded better with the dual regimen (92 percent vs 76 percent). [Gut 2020;69:1019-1026] According to a study from Thailand, a 58-percent H. pylori eradication rate was achieved with a 14-day P-CAB-based triple therapy.

Taking both the Maastricht V recommendation and data on vonoprazan into context, the team sought to evaluate the efficacy of a vonoprazan and bismuth-containing quadruple therapy for H. pylori eradication in Thailand.

Sixty-two dyspeptic patients (mean age 55 years, 49 percent female) who underwent upper gastrointestinal endoscopy and had H. pylori infection were randomized 1:1 to receive vonoprazan 20 mg BID for either 7 or 14 days, on top of a regimen containing bismuth subsalicylate 1,048 mg BID, metronidazole 400 mg TID, and tetracycline 500 mg QID. [APDW 2021, abstract 957-494]

Overall, H. pylori eradication rate with the 7-day regimen was 82 percent, while the 14-day regimen generated a 93-percent eradication rate. When compared against eradication rates of other antibiotic regimens, the 14-day vonoprazan-based regimen yielded a 100-percent eradication rate. “[The] 14-day regimen could overcome the effect of clarithromycin-, quinolone-, and metronidazole-resistant strains,” said Tungtrongchitr.

Moreover, eradication rates with the 14-day regimen remained high irrespective of CYP3A4/5 genetic polymorphism, reaching as high as 100 percent for CYP3A4 genotype EM* and CYP3A5 genotype IM*, he added.

Compared with the 7-day regimen, the rates of adverse events (AEs) were higher with the 14-day regimen, the most common being black stools (33 percent vs 24 percent), diarrhoea (14 percent vs 12 percent), and bitter taste (24 percent vs 9 percent). Nonetheless, AEs were manageable, and none were serious.

“[Taken together,] this 14-day vonoprazan-based quadruple regimen could be used as an alternative first-line treatment for H. pylori eradication,” concluded Tungtrongchitr.