High Hopes for New H Pylori Treatments

Colin W. Howden, MD

A pair of treatment regimens recently approved by the US Food and Drug Administration (FDA) for Helicobacter pylori (H pylori) infections are showing promise bringing up the cure rate for infected patients.

In a product showcase during the 2022 American College of Gastroenterology (ACG) Annual Meeting in Charlotte sponsored by Phathom Pharmaceuticals, Colin W. Howden, MD, FRCP (Glasg.), FACP, AGAF, FACG, FCP, Hyman Professor Medicine and Chief, Division of Gastroenterology, University of Tennessee Health Science Center, explained how there is now a great need for H pylori treatments.

“Treatment of H pylori is evolving,” Howden said. “The still today, the most commonly prescribed regimen for H pylori infection in the US and much of Europe is so called traditional triple therapy, which comprises a proton pump inhibitor, amoxicillin and clarithromycin or sometimes a PPI, metronidazole or clarithromycin.”

Early Treatments

Howden said when the treatments were initially developed, they were considered fairly reliable, with eradication rates of approximately 87% in clinical practice.

However, success rates since have subsequently declined to around 58%, largely because of resistance to clarithromycin.

Along with drug resistance, other challenges involving treatment is a lot of regimens involve a large number of pills taken at very specific times of the day. In addition, there are tolerability issues and acid suppression plays a big role.

“We've known for some time that acid suppression plays a key role in the eradication. of H. pylori infection,” Howden said. “And this dates back to studies from Europe in the 1990s, where when two antibiotics were given without acid suppression, eradication rates were about 40%. And when the same two antibiotics were given with a proton pump inhibitor eradication rates were about 80%.”

A Pair of New Regimens

However, in May the FDA approved 2 new treatments for adult patients with H pylori infections.

The first treatment option—voquezna triple pak, consists of vonoprazan, amoxicillin, clarithromycin. The second treatment option is the voquezna dual pack, which consists of vonoprazan and amoxicillin.

In clinical trials testing these treatment regimens, investigators found an eradication rate of 85% using the triple pak and an eradication rate of 79% using the dual pak in patients with sensitive strains of H pylori.

For safety, Howden said the adverse events were similar to what is seen in gastrointestinal medications, with diarrhea being the most commonly occurring adverse event related to treatment.

“So to summarize, vonoprazan is a potassium competitive acid blocker is the first of these drugs to be approved by the US Food and Drug Administration and had a pharmacodynamic study and healthy volunteers that provide the rapid potent and durable acid suppression,” Howden said. “It starts to suppress gastric acid secretion within about two to three hours of the first oral dose that achieved steady state acid suppression by around day four with a mean intragastric pH of six and control of intragastric pH is maintained over a 24 hour period.”

It is currently estimated that approximately 30% of adults in the US are infected with H pylori. However, those infection rates differ based on region, as well as based on racial and ethnic backgrounds and economic difficulties.

One of the main challenges in treating the disease is that it does not have specific gastrointestinal symptoms associated with it and up to 90% of patients with H pylori infections are asymptomatic.