Low-Dose Minocycline Can Replace Tetracycline in Refractory H. pylori Rescue Therapy: JGH | October 2026

What Did the Study Find?

This trial randomised 480 patients with refractory H. pylori infection after multiple treatment failures to four 14-day vonoprazan–bismuth quadruple regimens. Classical therapy used tetracycline 400 mg four times daily plus metronidazole 500 mg four times daily; three experimental groups substituted different minocycline and metronidazole doses.

Intention-to-treat eradication rates were 90.0% with classical tetracycline therapy and 92.5%, 90.8% and 91.7% with the three minocycline regimens. Corresponding per-protocol rates were 98.2%, 97.4%, 97.2% and 96.4%, confirming noninferiority. Metronidazole resistance did not materially reduce efficacy. The least intensive regimen—minocycline 50 mg twice daily plus metronidazole 400 mg three times daily—had the lowest overall adverse-event incidence while maintaining comparable eradication and adherence. Wiley Online Library

Why Does It Matter?

Tetracycline availability and a demanding four-times-daily schedule can limit optimised bismuth quadruple therapy. Low-dose minocycline provides a practical rescue alternative with a somewhat simpler regimen. However, this was a Chinese study using vonoprazan, and antibiotic-resistance patterns, drug availability and prior-treatment histories may differ substantially elsewhere.

GastroAGI Takeaway

When tetracycline is unavailable, low-dose minocycline-based vonoprazan–bismuth quadruple therapy is an evidence-supported rescue option—but local resistance and previous antibiotic exposure still matter.