A large, phase 3 clinical trial revealed that dual therapy with vonoprazan and amoxicillin or triple therapy of vonoprazan, amoxicillin, and clarithromycin outperformed traditional triple or quadruple therapy regimens that did not include vonoprazan, William D. Chey, MD, FACG, said at the American College of Gastroenterology (ACG) scientific meeting Oct. 25.

Dr Chey is a professor of medicine and director of the GI Physiology Laboratory at the University of Michigan.

The abstract Dr Chey presented, “Vonoprazan Dual and Triple Therapy for H pylori Eradication," received the ACG Governors Award for Excellence in Clinical Research.

He explained that eradication rates for Helicobacter pylori (H pylori) have fallen to under 80% in the United States, largely due to increasing resistance to clarithromycin, an integral agent in traditional triple therapy.

The clinical trial’s aim was to compare the efficacy of dual therapy incorporating vonoprazan and amoxicillin, and triple therapy containing vonoprazan, amoxicillin, and clarithromycin against traditional therapy.

The primary endpoint of the research was noninferiority of these regimens to traditional triple therapy among patients without resistant strains of H pylori, Dr Chey stressed. The secondary endpoint was to demonstrate if the vonoprazan regimens demonstrated superiority to traditional therapy, again among patients without resistant strains of H pylori.

The study included 1046 patients in the US and Europe, randomized roughly equally into the 3 treatment groups. All participants were aged 18 years or over, were treatment naïve, and had a history of dyspepsia or peptic ulcer that had not been treated.

“The rate of clarithromycin resistance was higher than traditionally thought in the US,” Dr Chey stated. “It was present in 20+% of the patients.”

Both vonoprazan arms proved noninferior, with the highest eradication rate of 84.7% seen in the group receiving triple vonoprazan therapy. The vonoprazan regimens also proved superior to traditional triple, Dr Chey said. And among patients with resistant strains of H pylori, both types of vonoprazan therapy were more likely to lead to eradication.

All the regimens tests were well tolerated, with no serious or severe side effects.

“Nearly a third of patients fail traditional triple therapy,” Dr Chey stated. “Vonoprazan could provide an important alternative treatment.”

The sponsor has submitted a New Drug Application to the US Food and Drug Administration for vonoprazan, he added.

--Rebecca Mashaw

Chey, WD. (S1382) Vonoprazan dual and triple therapy for Helicobacter pylori eradication. Presented at the American College of Gastroenterology Scientific Meeting. October 25, 2021.