Combination Treatment Achieves High Rate of H. pylori Eradication

Studies have shown that nearly half of the world population could be infected with H. pylori, increasing those individuals’ risk of chronic gastritis, peptic ulcer, and gastric cancer. Because the evidence shows there is strong benefit from eradication of H. pylori, clinicians should implement therapeutic regimens that can achieve high rates of eradication (at least 90-95%).

However, the authors of “Miscellaneous Therapy Is Highly Successful for Helicobacter Pylori Eradication,” published in Alimentary Pharmacology and Therapeutics, report studies have shown that “different treatment regimens have not been able to achieve these rates,” and that the standard combination therapy “based on PPIs, clarithromycin and amoxicillin or metronidazole” achieves only about a 70% eradication rate.

To improve H. pylori eradication rates, the authors designed a treatment regimen that takes into account “the unique peculiarities” of H. pylori and is specifically designed to avoid phenotypic resistance.

For the study, 122 adult patients (68% female) with confirmed H. pylori infection and symptoms of acid-peptic disease received a diagnostic upper endoscopy upon enrollment and another at least four weeks post-treatment. Researchers also obtained biopsies for rapid urease tesing and histological examination. Patients who had previously failed H. pylori eradication therapy, who were taking proton pump inhibitors, or who were on antiobiotics were excluded.

Patients received the following treatment:

• Days 1-5: Lansoprazole 30 mg, b.d., amoxicillin 1 g, b.d., metronidazole 500 mg, t.d.s.
• Days 6-10: Lansoprazole 30 mg, q.d.s. and metronidazole 500 mg, t.d.s.
• Days 11-15: Lansoprazole 30 mg, b.d., clarithromycin 500 mg, b.d., metronidazole 500 mg t.d.s.

Patients completed questionnaires to record the intake of the medications and the development of adverse effects. Adequate treatment adherence was defined for the study as 90% or greater intake of medication. The researchers measured the percentage of H. pylori infection eradication at four weeks post-treatment, with a cure rate of ≥95% defined as successful eradication.

A total of 118 patients completed treatment. Baseline endoscopy identified follicular gastritis in 60 patients (51%), diffuse antral gastritis in 32 (27%), multifocal gastritis in 12 (10%), and peptic ulcer in 14 (12%). The authors reported that the rate of eradication in the treatment group was 94.06% (111/118), with a range of 90—98.3% (CI of 95%).

Treatment adherence was confirmed in 96% of patients. More than half (65/118) of patients reported at least one adverse event, with nausea, abdominal pain, and diarrhea the most common.

In their discussion of these results, the authors noted that H. pylori can be difficult to eradicate for a variety of reasons, including noncompliance with treatment, antibiotic resistance (especially to metronidazole and clarithromycin, with studies showing clarithromycin resistance approaching 20% in some parts of the world), genetic variability, and polymorphism of CYP 2C19.

The treatment protocol for this study included high doses of metronidazole throughout the 15-day cycle in order to overcome resistance to imidazoles. The increasing dose of PPI was intended to “favour the alkalinization of the environment, allowing the bacteria to go from persistent into replicative states and thus rendering them, susceptible to be eradicated by the antibiotic.”

The authors concluded that the results of this study “suggest that a miscellaneous therapy for patients with H. pylori infection is highly effective. This approach takes into account the specific characteristics of the bacteria and their milieu, and tackles an important drawback of resistance and failure of current treatment regimens. Further large-scale prospective studies in other populations assessing the efficacy and safety of the miscellaneous therapy for H. pylori are needed to confirm these results and firmly establish the role of this therapeutic regimen in patients with H. pylori.”