Dual Clarithromycin and Metronidazole Resistance Is the Main Cause of Failure in Ultimate Helicobacter pylori Eradication

Real-world efficacy of second-line therapies for Helicobacter pylori: a population-based study

BACKGROUND

With the increasing prevalence of antibiotic resistance, real-world data on the optimal empirical second-line therapy for Helicobacter pylori are still limited.

OBJECTIVES

To evaluate the real-world efficacy of various second-line therapies for H. pylori.

PATIENTS AND METHODS

This was a retrospective population-based cohort study of all H. pylori-infected patients who had received the second-line treatment after the failure of primary clarithromycin triple therapy in Hong Kong between 2003 and 2018. The retreatment success rates of different second-line therapies were evaluated.

RESULTS

A total of 7591 patients who received second-line treatment were included. Notably, the most commonly prescribed regimen was still clarithromycin triple therapy, but the frequency of use had decreased from 59.5% in 2003-06 to 28.7% in 2015-18. Concomitant non-bismuth quadruple therapy had emerged as the commonest regimen (from 3.3% to 43.9%). In a validation analysis, the sensitivity and specificity of retreatment-inferred second-line treatment failure were 88.3% and 97.1%, respectively. The overall success rate of second-line therapies was 73.6%. Bismuth quadruple therapy had the highest success rate of 85.6%, while clarithromycin triple therapy had the lowest success rate of 63.5%. Specifically, bismuth/metronidazole/tetracycline quadruple, metronidazole/tetracycline triple, levofloxacin/metronidazole/tetracycline quadruple, rifabutin/amoxicillin triple and amoxicillin/levofloxacin triple therapies had relatively higher success rates over 80%. Age, treatment duration, baseline conditions and first-line treatment used were associated with success rate.

CONCLUSIONS

Bismuth quadruple therapy was the most effective second-line regimen for H. pylori in this real-world study. Despite a very low success rate, clarithromycin-containing triple therapies were still commonly used as second-line regimens.

A randomised controlled clinical study of standard triple therapy, bismuth-based quadruple therapy and sequential therapy for Helicobacter pylori infection in children

BACKGROUND AND AIM

Bismuth and non-bismuth quadruple therapy are the guideline-recommended first-line therapy in children with Helicobacter pylori infection in areas with high antibiotic resistance. However, their efficacy in children is uncertain and there are few well-designed studies. Here, we evaluated the eradication rates of standard triple therapy, bismuth-based quadruple therapy and sequential therapy in children with H. pylori infection.

METHODS

A randomised controlled trial was conducted in children infected with H. pylori in West China Second Hospital. They were randomly assigned to 14-day standard triple therapy (omeprazole + amoxicillin + clarithromycin), 14-day bismuth quadruple therapy (bismuth + omeprazole + amoxicillin + clarithromycin) and 10-day sequential therapy (omeprazole + amoxicillin for 5 days followed by omeprazole + clarithromycin + metronidazole for 5 days). The eradication rate was assessed by a 13C-urea breath test 4 to 6 weeks after therapy completion. Symptom improvement and adverse events were compared among the groups.

RESULTS

In total, 132 patients were enrolled. The eradication rates of 14-day standard triple therapy, 14-day bismuth quadruple therapy and 10-day sequential therapy were 70.0%, 78.9% and 50.0% in per-protocol analysis and 63.6%, 68.2% and 43.2% in intention-to-treat analysis, respectively. Symptom improvement and adverse drug event rates were similar in the three groups.

CONCLUSION

The three therapeutic regimens evaluated in this study are equally not recommendable for H. pylori infection treatment due to unsatisfactory eradication rates. The high prevalence of clarithromycin resistance makes the use of clarithromycin-based quadruple therapy not advisable, even in combination with amoxicillin and bismuth salts.

A deep learning-driven discovery of berberine derivatives as novel antibacterial against multidrug-resistant Helicobacter pylori

Helicobacter pylori (H. pylori) is currently recognized as the primary carcinogenic pathogen associated with gastric tumorigenesis, and its high prevalence and resistance make it difficult to tackle. A graph neural network-based deep learning model, employing different training sets of 13,638 molecules for pre-training and fine-tuning, was aided in predicting and exploring novel molecules against H. pylori. A positively predicted novel berberine derivative 8 with 3,13-disubstituted alkene exhibited a potency against all tested drug-susceptible and resistant H. pylori strains with minimum inhibitory concentrations (MICs) of 0.25-0.5 μg/mL. Pharmacokinetic studies demonstrated an ideal gastric retention of 8, with the stomach concentration significantly higher than its MIC at 24 h post dose. Oral administration of 8 and omeprazole (OPZ) showed a comparable gastric bacterial reduction (2.2-log reduction) to the triple-therapy, namely OPZ + amoxicillin (AMX) + clarithromycin (CLA) without obvious disturbance on the intestinal flora. A combination of OPZ, AMX, CLA, and 8 could further decrease the bacteria load (2.8-log reduction). More importantly, the mono-therapy of 8 exhibited comparable eradication to both triple-therapy (OPZ + AMX + CLA) and quadruple-therapy (OPZ + AMX + CLA + bismuth citrate) groups. SecA and BamD, playing a major role in outer membrane protein (OMP) transport and assembling, were identified and verified as the direct targets of 8 by employing the chemoproteomics technique. In summary, by targeting the relatively conserved OMPs transport and assembling system, 8 has the potential to be developed as a novel anti-H. pylori candidate, especially for the eradication of drug-resistant strains.

Vonoprazan-amoxicillin dual regimen with Saccharomyces boulardii as a rescue therapy for Helicobacter pylori: Current perspectives and implications

Yu et al's study in the World Journal of Gastroenterology (2023) introduced a novel regimen of Vonoprazan-amoxicillin dual therapy combined with Saccharomyces boulardii (S. boulardii) for the rescue therapy against Helicobacter pylori (H. pylori), a pathogen responsible for peptic ulcers and gastric cancer. Vonoprazan is a potassium-competitive acid blocker renowned for its rapid and long-lasting acid suppression, which is minimally affected by mealtime. Compared to proton pump inhibitors, which bind irreversibly to cysteine residues in the H+/K+-ATPase pump, Vonoprazan competes with the K+ ions, prevents the ions from binding to the pump and blocks acid secretion. Concerns with increasing antibiotic resistance, effects on the gut microbiota, patient compliance, and side effects have led to the advent of a dual regimen for H. pylori. Previous studies suggested that S. boulardii plays a role in stabilizing the gut barrier which improves H. pylori eradication rate. With an acceptable safety profile, the dual-adjunct regimen was effective regardless of prior treatment failure and antibiotic resistance profile, thereby strengthening the applicability in clinical settings. Nonetheless, S. boulardii comes in various formulations and dosages, warranting further exploration into the optimal dosage for supplementation in rescue therapy. Additionally, larger, randomized, double-blinded controlled trials are warranted to confirm these promising results.

Efficacy and safety of triple therapy containing berberine, amoxicillin, and vonoprazan for Helicobacter pylori initial treatment: A randomized controlled trial

BACKGROUND

With the development of traditional Chinese medicine research, berberine has shown good efficacy and safety in the eradication of Helicobacter pylori (H. pylori). The present study aimed to evaluate the efficacy and safety of triple therapy containing berberine, amoxicillin, and vonoprazan for the initial treatment of H. pylori.

METHODS

This study was a single-center, open-label, parallel, randomized controlled clinical trial. Patients with H. pylori infection were randomly (1:1:1) assigned to receive berberine triple therapy (berberine 500 mg, amoxicillin 1000 mg, vonoprazan 20 mg, A group), vonoprazan quadruple therapy (vonoprazan 20 mg, amoxicillin 1000 mg, clarithromycin 500 mg, colloidal bismuth tartrate 220 mg, B group), or rabeprazole quadruple therapy (rabeprazole 10 mg, amoxicillin 1000 mg, clarithromycin 500 mg, colloidal bismuth tartrate 220 mg, C group). The drugs were taken twice daily for 14 days. The main outcome was the H. pylori eradication rate. The secondary outcomes were symptom improvement rate, patient compliance, and incidence of adverse events. Furthermore, factors affecting the eradication rate of H. pylori were further analyzed.

RESULTS

A total of 300 H. pylori-infected patients were included in this study, and 263 patients completed the study. An intention-to-treat (ITT) analysis showed that the eradication rates of H. pylori in berberine triple therapy, vonoprazan quadruple therapy, and rabeprazole quadruple therapy were 70.0% (70/100), 77.0% (77/100), and 69.0% (69/100), respectively. The per-protocol (PP) analysis showed that the eradication rates of H. pylori in these three groups were 81.4% (70/86), 86.5% (77/89), and 78.4% (69/88), respectively. Both ITT analysis and PP analysis showed that the H. pylori eradication rate did not significantly differ among the three groups (P >0.05). In addition, the symptom improvement rate, overall adverse reaction rate, and patient compliance were similar among the three groups (P >0.05).

CONCLUSIONS

The efficacy of berberine triple therapy for H. pylori initial treatment was comparable to that of vonoprazan quadruple therapy and rabeprazole quadruple therapy, and it was well tolerated. It could be used as one choice of H. pylori initial treatment.

Antibiotic Resistance, Susceptibility Testing and Stewardship in Helicobacter pylori Infection

Despite the declining trend of Helicobacter pylori (H. pylori) prevalence around the globe, ongoing efforts are still needed to optimize current and future regimens in view of the increasing antibiotic resistance. The resistance of H. pylori to different antibiotics is caused by different molecular mechanisms, and advancements in sequencing technology have come a far way in broadening our understanding and in facilitating the testing of antibiotic susceptibility to H. pylori. In this literature review, we give an overview of the molecular mechanisms behind resistance, as well as discuss and compare different antibiotic susceptibility tests based on the latest research. We also discuss the principles of antibiotic stewardship and compare the performance of empirical therapies based on up-to-date resistance patterns and susceptibility-guided therapies in providing effective H. pylori treatment. Studies and clinical guidelines should ensure that the treatment being tested or recommended can reliably achieve a pre-agreed acceptable level of eradication rate and take into account the variations in antibiotic resistance across populations. Local, regional and international organizations must work together to establish routine antibiotic susceptibility surveillance programs and enforce antibiotic stewardship in the treatment of H. pylori, so that it can be managed in a sustainable and efficient manner.

Efficacy and safety of triple therapy containing berberine hydrochloride, amoxicillin, and rabeprazole in the eradication of Helicobacter pylori

OBJECTIVE

To estimate the effectiveness and safety of triple therapy containing berberine, amoxicillin, and rabeprazole in the eradication of Helicobacter pylori (H. pylori).

METHODS

This prospective, randomized controlled, open-label, noninferiority trial included treatment-naive patients with H. pylori infection who were randomly allocated at a ratio of 1:1 into the berberine triple therapy group (berberine hydrochloride 300 mg thrice daily, amoxicillin 1 g twice daily, and rabeprazole 10 mg twice daily) or standard bismuth-containing quadruple therapy group (amoxicillin 1 g twice daily, rabeprazole 10 mg twice daily, clarithromycin 500 mg twice daily, and bismuth tartrate 200 mg twice daily) for 14 days. Negative ¹³ C/¹⁴ C-urea breath test at 4 weeks after completion of the therapy was regarded as successful eradication.

RESULTS

Altogether 262 and 262 patients received berberine triple therapy and bismuth-containing quadruple therapy, respectively. Both intention-to-treat (79.8% vs 80.9%, P = 0.742) and per-protocol analyses (83.6% and 85.1%, P = 0.636) showed comparable eradication rate between the two groups, indicating a noninferior eradication rate (the lower limit of the 95% confidence interval over -10% [-7.9% and -7.87%, respectively]). Adverse events more commonly occurred in the bismuth-containing quadruple-therapy group (8.8% vs 16.0%, P = 0.012), while patient compliance and symptom improvement of the two regimens were comparable.

CONCLUSION

Triple therapy containing berberine, amoxicillin and rabeprazole is noninferior to bismuth-containing quadruple therapy in the initial treatment for H. pylori eradication.

Effect of metronidazole resistance on Helicobacter pylori eradication regimens

OBJECTIVES

Guidelines suggest bismuth-containing quadruple therapy (BQT) or concomitant therapy (CT) as first-line therapy in our geographic area. Both schedules contain metronidazole. We aimed to evaluate the effect of metronidazole resistance to Helicobacter pylori (H. pylori) eradication therapy.

METHODS

We recruited treatment-naïve subjects with H. pylori infection who received either CT or BQT during January 2020 and December 2021. Before therapy, a fecal sample was collected using the THD fecal test device from each patient. H. pylori DNA was extracted and mutations of rdxA and frxA genes and A2143G for metronidazole and clarithromycin resistance were investigated using real-time polymerase chain reaction with a high-resolution melting curve.

RESULTS

Ninety-six patients were enrolled, including 29 received BQT and 67 received CT. The overall eradication rate was 94.8% (100% for BQT and 92.5% for CT). Metronidazole resistance was found in 18 (18.8%) subjects, while clarithromycin resistance was found in 19 (19.8%). All 18 patients with metronidazole resistance achieved successful eradication (five treated with BQT and 13 with CT). The eradication rate in metronidazole-sensitive strains was 93.6%. Of these, 24 received BQT with 100% success, and 54 had CT with five failures (successful eradication in 90.7%). Two patients with treatment failure were resistant to clarithromycin, and the remaining three were susceptible to both clarithromycin and metronidazole. No statistical significance was observed in the eradication rate between metronidazole-resistant and -sensitive strains (100% vs 93.6%, P = 0.58).

CONCLUSION

Metronidazole resistance does not influence the eradication rate of BQT and CT regimens in our geographical area, even if such results need to confirmed in a larger sample.

Clinical Factors Implicated in Antibiotic Resistance in Helicobacter pylori Patients

Helicobacter pylori is a common gastric pathogen associated with multiple clinical syndromes, including cancer. Eradication rates of H. pylori remain suboptimal despite the progress made in the past few decades in improving treatment strategies. The low eradication rates are mainly driven by antibiotic resistance of H. pylori. Non-invasive molecular testing to identify patients with antibiotic-resistant H. pylori represents a promising therapeutic avenue, however this technology currently remains limited by availability, costs, and lack of robust validation. Moreover, there is insufficient evidence to demonstrate that resistance-testing-based treatment approaches are superior to appropriately designed empiric strategies. Consensus guidelines recommend use of proven locally effective regimens; however, eradication data are inconsistently generated in several regions of the world. In this review, we describe several clinical factors associated with increased rates of antibiotic resistant H. pylori, including history of previous antibiotic exposure, increasing age, female gender, ethnicity/race, extent of alcohol use, and non-ulcer dyspepsia. Assessment of these factors may aid the clinician in choosing the most appropriate empiric treatment strategy for each patient. Future study should aim to identify locally effective therapies and further explore the clinical factors associated with antibiotic resistance.

Myricetin as an Antivirulence Compound Interfering with a Morphological Transformation into Coccoid Forms and Potentiating Activity of Antibiotics against Helicobacter pylori

Helicobacter pylori, a gastric pathogen associated with a broad range of stomach diseases, has a high tendency to become resistant to antibiotics. One of the most important factors related to therapeutic failures is its ability to change from a spiral to a coccoid form. Therefore, the main aim of our original article was to determine the influence of myricetin, a natural compound with an antivirulence action, on the morphological transformation of H. pylori and check the potential of myricetin to increase the activity of antibiotics against this pathogen. We observed that sub-minimal inhibitory concentrations (sub-MICs) of this compound have the ability to slow down the process of transformation into coccoid forms and reduce biofilm formation of this bacterium. Using checkerboard assays, we noticed that the exposure of H. pylori to sub-MICs of myricetin enabled a 4–16-fold reduction in MICs of all classically used antibiotics (amoxicillin, clarithromycin, tetracycline, metronidazole, and levofloxacin). Additionally, RT-qPCR studies of genes related to the H. pylori morphogenesis showed a decrease in their expression during exposure to myricetin. This inhibitory effect was more strongly seen for genes involved in the muropeptide monomers shortening (csd3, csd6, csd4, and amiA), suggesting their significant participation in the spiral-to-coccoid transition. To our knowledge, this is the first research showing the ability of any compound to synergistically interact with all five antibiotics against H. pylori and the first one showing the capacity of a natural substance to interfere with the morphological transition of H. pylori from spiral to coccoid forms.