Meta-analysis of first-line triple therapy for helicobacter pylori eradication in Korea: is it time to change?

Safety profile of Helicobacter pylori eradication treatments: literature review and updated data of the European Registry on Helicobacter pylori management (Hp-EuReg)

INTRODUCTION

Helicobacter pylori (H. pylori), the most prevalent chronic infection globally, is the major cause of relevant diseases such as gastric cancer, leading to high morbidity and mortality worldwide. Several studies have focused on optimize H. pylori eradication treatment through combination therapies and antibiotic resistance. However, the adverse events profile and its impact, as a primary outcome, remains underexplored.The aim of this review was to summarize the available data on the safety of the most common regimens for H. pylori eradication and its impact on the compliance.

AREAS COVERED

This review encompassed the published evidence from the years 2008 to 2023 regarding both the safety and compliance for most common H. pylori eradication regimens. The main sources for this review comprised MEDLINE, PubMed, and Cochrane electronic databases. Furthermore, it included a safety analysis of unpublished data from the European Registry on H. pylori management (Hp-EuReg).

EXPERT OPINION

Poor compliance is correlated with significantly lower cure rates, and this is a unique modifiable source of H. pylori treatment failure. Eradication treatments have become complex, involving multiple drugs and dosing intervals. Thus, patient education is crucial; doctors must explain to the patient about potential temporary and most often harmless side effects.

Bismuth add-on improves the efficacy of 2-week tegoprazan-based triple therapy for first-line Helicobacter pylori eradication: a real-world evidence study

BACKGROUND

This study aimed to investigate the efficacy of bismuth added to a 2-week triple therapy consisting of tegoprazan (TPZ), amoxicillin, and clarithromycin for first-line Helicobacter pylori eradication.

RESEARCH DESIGN AND METHODS

We reviewed the retrospective data of patients who received a 2-week TPZ-based triple therapy with or without 300 mg bismuth twice daily. The primary endpoint was the H. pylori eradication rate of adding bismuth to the TPZ-based triple regimen (TAC-B group), compared to no bismuth added (TAC group).

RESULTS

In total, 306 and 256 patients were included in the intention-to-treat (ITT) and per-protocol (PP) analyses, respectively. The eradication success rates were significantly higher in the TAC-B group than in the TAC group (ITT, 82.9% vs. 71.8%, p = 0.029; PP, 95.8% vs. 87.5%, p = 0.027, respectively). The adherence rate to the eradication regimen was 100% in the TAC-B group and 97.0% in the TAC group. The adverse drug event rate in the TAC-B group was comparable to that in the TAC group (29.2% vs. 27.3%, p = 0.742). No use of bismuth was significantly associated with eradication failure (p = 0.038).

CONCLUSIONS

The bismuth add-on increased the first-line H. pylori eradication rate of 2-week TPZ-based triple therapy.

CLINICAL TRIAL REGISTRATION

www.clinicaltrials.gov identifier is NCT05453994.

Antibiotic Resistance of Helicobacter pylori: Mechanisms and Clinical Implications

Helicobacter pylori is a pathogenic bacterium associated with various gastrointestinal diseases, including chronic gastritis, peptic ulcers, mucosa-associated lymphoid tissue lymphoma, and gastric cancer. The increasing rates of H. pylori antibiotic resistance and the emergence of multidrug-resistant strains pose significant challenges to its treatment. This comprehensive review explores the mechanisms underlying the resistance of H. pylori to commonly used antibiotics and the clinical implications of antibiotic resistance. Additionally, potential strategies for overcoming antibiotic resistance are discussed. These approaches aim to improve the treatment outcomes of H. pylori infections while minimizing the development of antibiotic resistance. The continuous evolution of treatment perspectives and ongoing research in this field are crucial for effectively combating this challenging infection.

Practice guidelines for the management of Helicobacter pylori infection: The Saudi H. pylori Working Group recommendations

The eradication rates for Helicobacter pylori globally are decreasing with a dramatic increase in the prevalence of antibiotic resistant bacteria all over the world, including Saudi Arabia. There is no current consensus on the management of H. pylori in Saudi Arabia. The Saudi Gastroenterology Association developed these practice guidelines after reviewing the local and regional studies on the management of H. pylori. The aim was to establish recommendations to guide healthcare providers in managing H. pylori in Saudi Arabia. Experts in the areas of H. pylori management and microbiology were invited to write these guidelines. A literature search was performed, and all authors participated in writing and reviewing the guidelines. In addition, international guidelines and consensus reports were reviewed to bridge the gap in knowledge when local and regional data were unavailable. There is limited local data on treatment of H. pylori. The rate of clarithromycin and metronidazole resistance is high; therefore, standard triple therapy for 10-14 days is no longer recommended in the treatment of H. pylori unless antimicrobial susceptibility testing was performed. Based on the available data, bismuth quadruple therapy for 10-14 days is considered the best first-line and second-line therapy. Culture and antimicrobial susceptibility testing should be considered following two treatment failures. These recommendations are intended to provide the most relevant evidence-based guidelines for the management of H. pylori infection in Saudi Arabia. The working group recommends further studies to explore more therapeutic options to eradicate H. pylori.

Approach to Patients with Consecutive Helicobacter pylori Eradication Failure

<i>Helicobacter pylori</i> (<i>H. pylori</i>) is associated with various gastrointestinal disorders, such as gastritis, peptic ulcers, mucosa-associated lymphoid tissue lymphoma, and gastric cancer. Therefore, the International Agency for Research on Cancer, a specialized cancer agency of the World Health Organization, categorizes <i>H. pylori</i> as a definite gastric carcinogen (group I). <i>H. pylori</i> eradication is a major challenge both medically and socioeconomically in countries with high prevalence of <i>H. pylori</i> and gastric cancer. However, the efficacy of first-line clarithromycin-containing triple therapy and second-line bismuth-containing quadruple therapy continues to decline worldwide including in Korea. The role of salvage therapy is being recognized globally; however, the exact salvage therapy which is useful in daily clinical practice remains unestablished. In this review, factors associated with eradication failure will be discussed. Furthermore, eradication regimens that may be useful as salvage therapies based on Korean guidelines, Maastricht VI/Florence consensus report and previous research are summarized.

Prediction of the Drug–Drug Interaction Potential between Tegoprazan and Amoxicillin/Clarithromycin Using the Physiologically Based Pharmacokinetic and Pharmacodynamic Model

Tegoprazan is a novel potassium-competitive acid blocker. This study investigated the effect of drug–drug interaction on the pharmacokinetics and pharmacodynamics of tegoprazan co-administered with amoxicillin and clarithromycin, the first-line therapy for the eradication of Helicobacter pylori, using physiologically based pharmacokinetic and pharmacodynamic (PBPK/PD) modeling. The previously reported tegoprazan PBPK/PD model was modified and applied. The clarithromycin PBPK model was developed based on the model provided by the SimCYP® compound library. The amoxicillin model was constructed using the middle-out approach. All of the observed concentration–time profiles were covered well by the predicted profiles with the 5th and 95th percentiles. The mean ratios of predicted to observed PK parameters, including the area under the curve (AUC), maximum plasma drug concentration (Cmax), and clearance, were within the 30% intervals for the developed models. Two-fold ratios of predicted fold-changes of Cmax and AUC from time 0 to 24 h to observed data were satisfied. The predicted PD endpoints, including median intragastric pH and percentage holding rate at pH above 4 or 6 on day 1 and day 7, were close to the corresponding observed data. This investigation allows evaluation of the effects of CYP3A4 perpetrators on tegoprazan PK and PD changes, thus providing clinicians with the rationale for co-administration dosing adjustment.

Management of Helicobacter pylori Infection: A Comparison between Korea and the United States

Helicobacter pylori has been well known to cause gastritis, peptic ulcers, mucosa-associated lymphoid tissue, and gastric cancer. The importance of H. pylori eradication has been emphasized; however, the management of H. pylori infection is difficult in clinical practice. In both Eastern and Western countries, there has been a constant interest in confirming individuals who should be tested and treated for H. pylori infection and developing methods to diagnose H. pylori infection. Many studies have been implemented to successfully eradicate H. pylori, and various combinations of eradication regimens for H. pylori infection have been suggested worldwide. Based on the findings of previous studies, a few countries have published their own guidelines that are appropriate for their country; however, these country-specific guidelines may differ depending on the circumstances in each country. Evidence-based guidelines and clinical practice updates for the treatment of H. pylori infection have been published in Korea and the United States in 2021. This review will summarize the similarities and differences in the management of H. pylori infection in Korea and the United States, focusing on indications, diagnosis, and treatments based on recent guidelines and recommendations in both countries.

Cost-Effectiveness of Empirical Bismuth-Based Quadruple Therapy and Tailored Therapy After Clarithromycin Resistance Tests for Helicobacter pylori Eradication

BACKGROUND

The eradication rate of clarithromycin-based standard triple therapy (STT) for Helicobacter pylori infection has decreased due to clarithromycin resistance (CR). We evaluated the cost-effectiveness of tailored therapy according to CR test results, and compared the results of STT with those of empirical bismuth quadruple therapy (BQT).

METHODS

The prospectively collected data of 490 H. pylori-positive patients with chronic gastritis or peptic ulcer disease were retrospectively analyzed. Among them, 292 patients underwent CR testing using dual-priming oligonucleotide-based polymerase chain reaction. The tailored group (n = 292) consisted of patients treated with STT for 7 days and BQT for 10 days as per their CR test results. The remaining patients were assigned to the empirical group (n = 198) and received BQT for 10 days without a CR test. The eradication rate, adverse events and medical costs associated with H. pylori eradication therapy were investigated.

RESULTS

In the tested patients (tailored group), the CR-positive rate was 32.2% (n = 94/292). The eradication rate according to an intention-to-treat analysis was 87.7% in the tailored group and 91.8% in the empirical group (P = 0.124); the respective rates were 94.4% and 97.9% by per-protocol analysis (P = 0.010). The frequency of adverse events was lower in the empirical group than the tailored group (35.1% vs. 52.7%, P < 0.001). Total per capita medical costs were $406.50 and $503.50, respectively.

CONCLUSIONS

Ten-day empirical BQT was more effective, safer, and less expensive than tailored therapy based on a CR test for H. pylori eradication.

Comparison of tailored Helicobacter pylori eradication versus modified bismuth quadruple therapy in Korea: a randomized controlled trial

OBJECTIVES

We aimed to compare the success rate, adverse drug events, and cost-effectiveness of tailored Helicobacter pylori eradication and modified bismuth-containing quadruple therapy.

METHODS

The diagnosis of H. pylori infection was randomly based on either rapid urease test (RUT) or dual priming oligonucleotide (DPO)-based multiplex polymerase chain reaction (PCR) in 1:1 ratio. According to the presence of point mutations that cause clarithromycin resistance, patients in the tailored therapy (TT) group received standard triple therapy or classic bismuth quadruple therapy. Patients with positive RUT results received 40 mg pantoprazole, 1000 mg amoxicillin, 750 mg metronidazole, and 600 mg bismuth subcitrate twice daily for 14 days (PAM-B therapy).

RESULTS

Between the TT (n = 141) and PAM-B groups (n = 141), H. pylori eradication rate did not differ significantly according to intention-to-treat (TT: 80.9% vs. PAM-B: 85.8%, P = 0.262), modified intention-to-treat (TT: 89.1% vs. PAM-B: 91.0%, P = 0.606), and per-protocol (TT: 89.0% vs. PAM-B: 93.5%, P = 0.198) analyses. The average cost for successful eradication was higher in the TT group than in the PAM-B group ($340.7 vs. $263.9 per patient).

CONCLUSION

PAM-B therapy exhibits similar efficacy and improved cost-effectiveness compared to TT based on the results of DPO-PCR tests.

CLINICAL TRIAL REGISTRATION

www.clinicaltrials.gov identifier is NCT05002595.

Probiotics as the live microscopic fighters against Helicobacter pylori gastric infections

Background

Helicobacter pylori (H. pylori) is the causative agent of stomach diseases such as duodenal ulcer and gastric cancer, in this regard incomplete eradication of this bacterium has become to a serious concern. Probiotics are a group of the beneficial bacteria which increase the cure rate of H. pylori infections through various mechanisms such as competitive inhibition, co-aggregation ability, enhancing mucus production, production of bacteriocins, and modulating immune response.

Result

In this study, according to the received articles, the anti-H. pylori activities of probiotics were reviewed. Based on studies, administration of standard antibiotic therapy combined with probiotics plays an important role in the effective treatment of H. pylori infection. According to the literature, Lactobacillus casei, Lactobacillus reuteri, Lactobacillus rhamnosus GG, and Saccharomyces boulardii can effectively eradicate H. pylori infection. Our results showed that in addition to decrease gastrointestinal symptoms, probiotics can reduce the side effects of antibiotics (especially diarrhea) by altering the intestinal microbiome.

Conclusion

Nevertheless, antagonist activities of probiotics are H. pylori strain-specific. In general, these bacteria can be used for therapeutic purposes such as adjuvant therapy, drug-delivery system, as well as enhancing immune system against H. pylori infection.

Pretreatment with Ranitidine Bismuth Citrate May Improve Success Rates of Helicobacter pylori Eradication: A Prospective, Randomized, Controlled and Open-Label Study

Effective Helicobacter pylori (H. pylori) eradication is a major public health concern; however, eradication failure rates with the standard triple therapy remain high. We aimed to investigate the effectiveness and tolerability of ranitidine bismuth citrate (RBC) pretreatment before standard triple therapy for H. pylori eradication. A prospective, randomized, controlled, and open-label clinical trial was conducted from June to December 2019. H. pylori eradication rate, safety, and tolerability were compared between the standard treatment group (esomeprazole, amoxicillin, and clarithromycin for 7 days) and RBC pretreatment group (RBC for 2 weeks before standard triple therapy). This trial ended earlier than estimated owing to the N-nitrosodimethylamine concerns with ranitidine. Success rates of H. pylori eradication were 80.9% and 67.3% in the RBC pretreatment (n = 47) and standard treatment (n = 52) (p = 0.126) groups, respectively. Our trial was discontinued earlier than planned; however, a statistical significance would be achieved by expansion of our data (p = 0.031) if patient enrollment numbers reached those initially planned. Adverse event rates were comparable between groups (25.5% in the pretreatment group vs. 28.8% in the standard treatment group), without serious event. Tolerability was excellent in both groups, recorded as 97.9% and 100% in the pretreatment and standard treatment groups, respectively. Compared with the standard triple regimen, RBC pretreatment for 2 weeks may achieve higher H. pylori eradication rates, with excellent safety and tolerability. However, this study necessitates further validation as it was discontinued early owing to the N-nitrosodimethylamine issues of ranitidine.

Efficacy of Seven-day High-dose Esomeprazole-based Triple Therapy versus Seven-day Standard Dose Non-esomeprazole-based Triple Therapy as the First-line Treatment of Patients with Helicobacter pylori Infection

Background/Aims

The rates of Helicobacter pylori (H. pylori) eradication have declined with the use of proton pump inhibitor- amoxicillin-clarithromycin as the first-line triple therapy. On the other hand, several studies have suggested that high gastric pH levels could affect the H. pylori eradication rate by enhancing the efficacy of antimicrobials. This study compared the efficacy of seven-day high-dose esomeprazole-based triple therapy (7-HEAC) for first-line H. pylori eradication with the seven-day standard dose non-esomeprazole-based triple therapy (7-NEAC) to identify the risk factors related to eradication failure.

Methods

This study included 223 patients who were diagnosed with a H. pylori infection and received 7-HEAC or 7-NEAC between June 2016 and January 2017. The H. pylori eradication rates, as well as demographic and clinical factors, were investigated retrospectively. H. pylori eradication was confirmed by a ¹³C-urea breath test or rapid urease test at least 4 weeks after the completion of therapy.

Results

The eradication rates were 67.7% (105/155; 95% CI 59.5-74.8%) in the 7-NEAC group and 80.9% (55/68; 95% CI 69.9-89.8%) in the 7-HEAC group (p=0.045). The adverse event rates were 5.8% (9/155) in the 7-NEAC group and 7.4% (5/68) in the 7-HEAC group (p=0.661). Multivariate analysis revealed being female (OR 2.08; 95% CI 1.15-3.76) to be associated with the failure of H. pylori eradication therapy.

Conclusions

The eradication rate of the 7-HEAC group was higher than that of the 7-NEAC group. Nevertheless, more effective first-line therapies may be necessary for H. pylori eradication in the near future.

Different dose of new generation proton pump inhibitors for the treatment of Helicobacter pylori infection: A meta-analysis

The evidence on whether high-dose new generation proton pump inhibitors (PPIs) including rabeprazole and esomeprazole achieve a higher eradication rate of Helicobacter pylori has not been assessed. The primary comparison was eradication and adverse events (AEs) rate of standard (esomeprazole 20 mg bid, rabeprazole 10 mg bid) versus high-dose (esomeprazole 40 mg bid, rabeprazole 20 mg bid) PPIs. Sub-analyses were performed to evaluate the eradication rate between Asians and Caucasians, clarithromycin-resistance (CAM-R) strains, and clarithromycin-sensitivity (CAM-S) strains of different dose PPIs. We conducted a literature search for randomized controlled trials comparing high-with standard-dose esomeprazole and rabeprazole for H. pylori eradication and AEs. A total of 12 trials with 2237 patients were included. The eradication rate of high-dose PPIs was not significantly superior to standard-dose PPIs regimens: 85.3% versus 84.2%, OR 1.09 (0.86–1.37), P = 0.47. The high dose induced more AEs than those of the standard dose, but didn’t reach statistical significance (OR 1.25, 95% CI: 0.99–1.56, P = 0.06). Subgroup analysis showed that the difference in eradication rate of PPIs between high- and standard-dose groups were not statistically significant both in Asians (OR 0.99, 95% CI 0.75–1.32, P = 0.97) and Caucasians (OR 1.27, 95% CI 0.84–1.92, P = 0.26). Furthermore, there were similar eradication rates in CAM-S (OR 1.2; 95% CI 0.58–2.5; P = 0.63) and CAM-R strains (OR 1.08; 95% CI 0.45–2.56; P = 0.87) between the standard-and high-dose groups. High and standard dosages of new generation of the PPIs showed similar H. pylori eradication rates and AEs as well as between Asian versus Caucasian populations, with or without clarithromycin-resistance. However, further studies are needed to confirm.

Adverse Event Profile During the Treatment of Helicobacter pylori: A Real-World Experience of 22,000 Patients From the European Registry on H. pylori Management (Hp-EuReg)

INTRODUCTION

The safety of Helicobacter pylori eradication treatments and to what extent adverse events (AEs) influence therapeutic compliance in clinical practice are hardly known. Our aim was to assess the frequency, type, intensity, and duration of AEs, and their impact on compliance, for the most frequently used treatments in the "European Registry on Helicobacter pylori management."

METHODS

Systematic prospective noninterventional registry of the clinical practice of European gastroenterologists (27 countries, 300 investigators) on the management of H. pylori infection in routine clinical practice. All prescribed eradication treatments and their corresponding safety profile were recorded. AEs were classified depending on the intensity of symptoms as mild/moderate/severe and as serious AEs. All data were subject to quality control.

RESULTS

The different treatments prescribed to 22,492 patients caused at least 1 AE in 23% of the cases; the classic bismuth-based quadruple therapy was the worst tolerated (37% of AEs). Taste disturbance (7%), diarrhea (7%), nausea (6%), and abdominal pain (3%) were the most frequent AEs. The majority of AEs were mild (57%), 6% were severe, and only 0.08% were serious, with an average duration of 7 days. The treatment compliance rate was 97%. Only 1.3% of the patients discontinued treatment due to AEs. Longer treatment durations were significantly associated with a higher incidence of AEs in standard triple, concomitant, bismuth quadruple, and levofloxacin triple or quadruple therapies.

DISCUSSION

Helicobacter pylori eradication treatment frequently induces AEs, although they are usually mild and of limited duration. Their appearance does not interfere significantly with treatment compliance.

Eradication Rates of Clarithromycin Triple Therapy in Korea: A Systematic Review and Meta-analysis

Background/Aims: Standard triple therapy, including a proton pump inhibitor, clarithromycin, and amoxicillin, has been recommended as the first-line for <i>Helicobacter pylori</i> infection. However, the eradication rate of standard triple therapy has declined over the past years because of the increasing resistance to clarithromycin in Korea. We analyzed the eradication rates and the 10-year change in the eradication rates in Korea.Methods: PubMed, EMBASE, the Cochrane Library, and KoreaMed were searched for studies published between January 2007 and June 2018. The pooled eradication rates and their 95% CIs were estimated using a random-effect logistic regression model.Results: Twenty-six randomized controlled studies on standard triple therapy conducted in Korea were selected. The intention-to-treat (ITT) and per protocol analyses showed pooled eradication rates of standard triple therapy of 71.6% (95% CI, 69.9~73.3%) and 79.6% (95% CI, 76.6~82.2%), respectively. The eradication rate decreased with time. The ITT analysis showed that the 14-day therapy (78.1% [95% CI, 75.2~80.7%]) had significantly higher eradication rates than the 7-day therapy (70.0% [95% CI, 68.5~71.4%]) (<i>P</i><0.01).Conclusions: These results suggest that the eradication rate of standard triple therapy, as the first-line therapy, has shown an unacceptable decrease. The eradication rate increased when the duration of therapy was increased to 14 days, but it was not satisfactory. Therefore, other treatment regimens or therapies based on susceptibility tests should be considered for the first-line therapy.

Ten-day bismuth-containing quadruple therapy versus 7-day proton pump inhibitor-clarithromycin containing triple therapy as first-line empirical therapy for the Helicobacter pylori infection in Korea: a randomized open-label trial

BACKGROUND

This randomized, open-label trial aimed to compare the efficacy of 10-day bismuth-containing quadruple therapy (BQT) with 7-day proton-pump inhibitor-clarithromycin containing standard triple therapy (STT) as an empirical first-line Helicobacter pylori therapy.

METHODS

Participants with H. pylori infection were randomly assigned to either 10-day BQT (daily doses of bismuth 300 mg, four times; lansoprazole 30 mg, twice; metronidazole 500 mg, three times; and tetracycline 500 mg, four times) or 7-day STT (lansoprazole 30 mg; amoxicillin 1,000 mg; and clarithromycin 500 mg; each given twice daily). Participants who failed initial therapy were crossed over to the alternative treatment regimen. Primary outcome was the eradication rates of first-line treatment by intention-to-treat analysis.

RESULTS

Study participants (n = 352) were randomized to receive either 10-day BQT (n = 175) or 7-day STT (n = 177). The BQT-group achieved a significantly higher eradication rate than the STT-group in the intention-to-treat analysis (74.3% vs 57.1%, respectively; P = 0.001), modified intention-to-analysis (87.2% [130/149] vs 68.7% [101/147], respectively; P < 0.001) and per-protocol analysis (92.9% [105/113] vs 70.1% [94/134], respectively; P < 0.001). Although there was no serious adverse event, the compliance was lower with BQT than STT as a higher proportion of participants in the BQT-group discontinued therapy because of adverse events than those in the STT-group (23.1% vs 9.1%, respectively; P = 0.001) CONCLUSIONS: Ten-day BQT had higher eradication rates compared to that of the 7-day STT as an empirical first-line treatment for H. pylori eradication in Korea.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02557932. Registered 23 September 2015, https://clinicaltrials.gov/ct2/show/NCT02557932?term=NCT02557932&draw=2&rank=1 .

Fermented-Rhus verniciflua extract ameliorate Helicobacter pylori eradication rate and gastritis

An antibacterial effect of fermented-Rhus verniciflua extract (FRVE), an urushiol-free extract fermented by Fomitella fraxinea, on Helicobacter pylori was evaluated in mice. Minimal inhibitory concentration of FRVE against H. pylori eradication was checked with serial dilution method in vitro. H. pylori infection-induced mice were utilized to determine the effect of oral administration of FRVE with/without standard triple therapy (STT: metronidazole, omeprazole, and clarithromycin) on H. pylori colonization and gastric inflammation. H. pylori was clearly eradicated by FRVE at a concentration of ≥2 mg/ml in vitro. In animal study, FRVE at a concentration of ≥6 mg/ml significantly reduced colonized H. pylori grading (0.2 vs. 2.2, p < .01) and improved gastric inflammation (0.4 vs. 1.6, p < .01) compared to control. STT with FRVE (3 mg/ml) exerted synergistic effect on both H. pylori colonization grade (STT, 0.6 ± 0.9; FRVE, 1.4 ± 0.5; STT + FRVE, 0.8 ± 0.4) and gastric inflammation (STT, 0.4 ± 0.5; FRVE, 1.4 ± 0.5; STT + FRVE,1.0 ± 0.1) compared with single therapy (p < .01). H. pylori eradication rate of FRVE (6 mg/ml) was higher than that of STT (60% vs. 20%). FRVE has potential antibacterial activity against H. pylori infection and can be used as an additional therapy on STT.

3-Pentylcatechol, a Non-Allergenic Urushiol Derivative, Displays Anti-Helicobacter pylori Activity In Vivo

We previously reported that 3-pentylcatechol (PC), a synthetic non-allergenic urushiol derivative, inhibited the growth of Helicobacter pylori in an in vitro assay using nutrient agar and broth. In this study, we aimed to investigate the in vivo antimicrobial activity of PC against H. pylori growing in the stomach mucous membrane. Four-week-old male C57BL/6 mice (n = 4) were orally inoculated with H. pylori Sydney Strain-1 (SS-1) for 8 weeks. Thereafter, the mice received PC (1, 5, and 15 mg/kg) and triple therapy (omeprazole, 0.7 mg/kg; metronidazole, 16.7 mg/kg; clarithromycin, 16.7 mg/kg, reference groups) once daily for 10 days. Infiltration of inflammatory cells in gastric tissue was greater in the H. pylori-infected group compared with the control group and lower in both the triple therapy- and PC-treated groups. In addition, upregulation of cytokine mRNA was reversed after infection, upon administration of triple therapy and PC. Interestingly, PC was more effective than triple therapy at all doses, even at 1/15th the dose of triple therapy. In addition, PC demonstrated synergism with triple therapy, even at low concentrations. The results suggest that PC may be more effective against H. pylori than established antibiotics.

The prolongation effect of ilaprazole-based standard triple therapy for Helicobacter pylori

BACKGROUND

Helicobacter pylori (HP) infection causes many diseases, such as peptic ulcers, gastritis and gastric cancer, and MALToma. It has been gradually accepted that all HP-infected patients should be treated because HP is regarded as an infection. Therefore, the importance of selecting the optimal treatment regimen has increased. Although the 14-day standard triple therapy (STT) is recommended in the current guidelines, prolonging treatment duration is controversial in real practice because of inconsistent results from previous data and the risk of adverse effects. Additionally, the effect of STT using ilaprazole has not been reported until now. We aimed to compare the eradication rate between 7 and 10 days STT using ilaprazole.

METHODS

A prospective randomized controlled trial was conducted, which was divided into 2 treatment groups: the control group was 7 days of STT, and the test group was 10 days of STT. The eradication regimen was 10 mg ilaprazole, 500 mg clarithromycin, and 1000 mg amoxicillin twice daily. We included patients who were diagnosed with positive results of H pylori examination. We compared the HP eradication rate according to treatment duration, CYP2C19 subtype and endoscopic diagnosis.

RESULTS

We enrolled a total of 254 patients consisting of 127 patients in each treatment arm. The eradication rates of the control and test groups were 65.4% (82/127) and 74.8% (95/127), respectively, in the intention-to-treat analysis (P = .1). In the per-protocol analysis, 70.3% (83/118) and 82.6% (94/115) were eradicated in each group, which was statistically significant (P = .027). The CYP2C19 subtype was examined in 230 patients. The eradication rate was 79.2% (57/72), 75.4% (92/122), and 72.2% (26/36) in each group, which was not significantly different (P = .704).

CONCLUSION

Ten-day STT was more effective than 7-day STT for HP eradication. The eradication rate was not affected by the CYP2C19 genotype.

Is Only Clarithromycin Susceptibility Important for the Successful Eradication of Helicobacter pylori?

Resistance to clarithromycin and other antibiotics included in the eradication regimen, such as amoxicillin and metronidazole, is important for Helicobacter pylori (H. pylori) eradication. The aim of this study was to investigate the correlation between the results of antimicrobial susceptibility testing and the eradication rate, as well as to understand the importance of antimicrobial susceptibility testing in H. pylori eradication. We retrospectively reviewed the electronic medical records of 1862 patients who underwent gastric biopsy for the culture of H. pylori during upper endoscopy from March 2015 to June 2019. We tried to find a correlation between the results of the antimicrobial susceptibility testing and the eradication rate in patients who received standard triple or concomitant therapy. A total of 247 patients exhibited positive results for culture and underwent antimicrobial susceptibility testing. Of these, 146 received eradication therapy, with follow-up tests after treatment. In the standard triple therapy, patients who were susceptible to both clarithromycin and amoxicillin exhibited significantly higher eradication rates (85.9%) than those susceptible to clarithromycin and resistant to amoxicillin (75.0%) or those resistant to clarithromycin and susceptible to amoxicillin (44.4%) (p = 0.013). In the concomitant therapy, patients who were susceptible to both clarithromycin and metronidazole had significantly higher eradication rates (96.3%) than those susceptible to clarithromycin and resistant to metronidazole (88.9%) or those resistant to clarithromycin and susceptible to metronidazole (50.0%) (p = 0.016). There was a correlation between the results of antimicrobial susceptibility testing and the eradication rate for H. pylori. In addition to clarithromycin, susceptibility to amoxicillin and metronidazole is also important for the successful eradication of H. pylori.

Amoxicillin or tetracycline in bismuth-containing quadruple therapy as first-line treatment for Helicobacter pylori infection

AIM

To compare the efficacy and safety between modified quadruple- and bismuth-containing quadruple therapy as first-line eradication regimen for Helicobacter pylori infection.

METHODS

This study was a multicenter, randomized-controlled, non-inferiority trial. Subjects endoscopically diagnosed with H. pylori infection were randomly allocated to receive modified quadruple- (rabeprazole 20 mg bid, amoxicillin 1 g bid, metronidazole 500 mg tid, bismuth subcitrate 300 mg qid [elemental bismuth 480 mg]; PAMB) or bismuth-containing quadruple therapy (rabeprazole 20 mg bid, bismuth subcitrate 300 mg qid, metronidazole 500 mg tid, tetracycline 500 mg qid; PBMT) for 14 days. Rates of eradication success and adverse events were investigated. Antibiotic resistance was determined using the agar dilution and DNA sequencing of the clarithromycin resistance point mutations in the 23 S rRNA gene of H. pylori.

RESULTS

In total, 233 participants were randomized, 27 were lost to follow-up, and four violated the protocol. Both regimens showed an acceptable eradication rate in the intention-to-treat (PAMB: 87.2% vs. PBMT: 82.8%, P = .37), modified intention-to-treat (96.2% vs. 96%, P > .99), and per-protocol (96.2% vs. 96.9%, P > .99) analyses. Non-inferiority in the eradication success between PAMB and PBMT was confirmed. The amoxicillin-, metronidazole-, tetracycline-, clarithromycin-, and levofloxacin-resistance rates were 8.3, 40, 9.4, 23.5, and 42.2%, respectively. Antimicrobial resistance did not significantly affect the efficacy of either therapy. Overall compliance was 98.1%. Adverse events were not significantly different between the two therapies.

CONCLUSION

Modified quadruple therapy comprising rabeprazole, amoxicillin, metronidazole, and bismuth is an effective first-line treatment for the H. pylori infection in regions with high clarithromycin and metronidazole resistance.

Impact of previous metronidazole exposure on metronidazole-based second-line quadruple therapy for Helicobacter pylori infection

BACKGROUND/AIMS

The negative effects on the eradication success of Helicobacter pylori infection after previous exposure to macrolides, including clarithromycin on clarithromycin-based first-line therapy have been demonstrated. However, whether this is true for metronidazole-based second-line quadruple therapy remains unclear. We investigated the relationship between past administration of metronidazole and the failure of metronidazole-based second-line quadruple therapy in patients with H. pylori infection.

METHODS

Patients over 20 years of age who were diagnosed with H. pylori infection between January 1998 and March 2016 were enrolled in this study. The relationship between the clinical parameters and the results of a C13-urea breath test after metronidazole-based second-line quadruple therapy was analyzed in patients for whom clarithromycin-based triple therapy failed to eradicate H. pylori.

RESULTS

The H. pylori eradication failure rate was significantly higher in patients with a history of metronidazole use than in patients without a history of metronidazole use (p = 0.011). Multivariable analysis showed that the odds ratio of previous metronidazole use for eradication failure was 3.468 (95% confidence interval, 1.391 to 8.649; p = 0.008). In the subgroup analysis of patients with a history of metronidazole use, the duration of metronidazole use and interval between its use and eradication therapy did not significantly affect H. pylori eradication failure.

CONCLUSION

Previous exposure to metronidazole was a significant risk factor for treatment failure of metronidazole-based second-line quadruple therapy; therefore, this should be considered when establishing a treatment strategy for patients with H. pylori infection.

Optimized diagnosis of Helicobacter pylori and tailored eradication therapy for preventing gastric cancer: a proposal for SHAKE strategy

INTRODUCTION

To decrease gastric cancer-related mortality, the Korean National Cancer Screening Program provides biennial screening gastroscopy to all individuals aged >40 years. However, a test-and-treat strategy of Helicobacter pylori for preventing gastric cancer has not been established.

AREAS COVERED

In this review, we present up-to-date results of endoscopic findings of H. pylori gastritis, optimal sites for H. pylori detection, gastric cancer risk assessment using serum pepsinogen, tailored eradication based on the antimicrobial resistance against H. pylori, and post-eradication surveillance.

EXPERT OPINION

Here we propose approaches to H. pylori diagnosis and treatment for preventing gastric cancer, termed 'Screening for H. pylori in Korea and Eradication (SHAKE)' strategy. This strategy consists of the following: (1) optimized H. pylori diagnosis, (2) individualized management based on the H. pylori infection status, and (3) tailored eradication therapy. H. pylori gastritis can be diagnosed by endoscopic observation of the gastric mucosal pattern at the greater curvature of the corpus. Measurement of the serum pepsinogen I/II ratio is useful for assessing the risk of gastric cancer. As a first-line treatment, tailored eradication based on the results of molecular testing is effective in a country with a high rate of clarithromycin-resistant H. pylori.

Genotypic and Phenotypic Resistance to Clarithromycin in Helicobacter pylori Strains

Background: The increasing prevalence of antimicrobial resistance, together with the lack of novel treatment options, negatively affects successful eradication of Helicobacter pylori. The aim of this study was to investigate genetic mutations in the 23S rRNA genes, which is associated with clarithromycin resistance, and to determine the clinical impact of genotype on phenotypic antimicrobial resistance. Methods: A total of 46 H. pylori strains were obtained from 13 patients, before and after unsuccessful eradication with clarithromycin-based triple therapy. The phenotypic resistance of each H. pylori strain was determined by minimum inhibitory concentration against clarithromycin using the serial two-fold agar dilution method. The genomic sequences of 23S rRNA genes were identified through next-generation sequencing, and nucleotide variants were determined based on comparison with genome sequences of the reference strain H. pylori 26695. Results: Clarithromycin resistance was found in 9 of 13 subjects before treatment and all subjects after unsuccessful eradication. Whole-genome sequencing of the 23S rRNA genes detected 42 mutations on 40 nonidentical loci, including 2147A>G (formerly 2143A>G) and 2146A>G (formerly 2142A>G). All strains with clarithromycin-resistant phenotype had either 2147A>G or 2146A>G mutation. When comparing genotype and phenotype for clarithromycin resistance, there was a significant association between 2147A>G mutation and clarithromycin-resistant phenotype. Conclusions: All clarithromycin-resistant strains had either 2146A>G or 2147A>G mutation, suggesting that tests targeting these two mutations may be enough for the prediction of clarithromycin resistance in this population.

Discovery of a Novel Mutation in DNA Gyrase and Changes in the Fluoroquinolone Resistance of Helicobacter pylori over a 14-Year Period: A Single Center Study in Korea

The efficacy of fluoroquinolone-based eradication therapy largely depends on the fluoroquinolone resistance of H. pylori. The aim of this study was to investigate the changes in the primary resistance rate of H. pylori to fluoroquinolone and the mechanism of resistance in Korea. A total of 153 strains and 48 strains of H. pylori were isolated at a tertiary hospital in 2005/2006 and 2017/2018, respectively. The minimum inhibitory concentrations (MICs) of fluoroquinolone were determined by the serial 2-fold agar dilution method. DNA sequences in the quinolone resistance-determining regions of gyrA/gyrB were analyzed in resistant strains. Subsequent natural transformation study was performed to determine the association between gyrase mutation and resistance. The resistance rates increased from 19.0% (29/153) to 43.8% (21/48) both for levofloxacin and moxifloxacin. The MIC values for resistant strains increased from 2–8 µg/mL to 4–16 µg/mL over time. Mutation of gyrA was detected in 93.1% (27/29) and 100% (21/21) among the resistant strains in both periods, respectively. A novel Gly-85 mutation of gyrA was found and confirmed to be associated with fluoroquinolone resistance. Fluoroquinolone resistance rate of H. pylori has markedly increased over time in Korea. The resistance is mostly due to the point mutation of gyrA. Fluoroquinolone-containing regimens should be carefully selected in Korea, considering the increasing fluoroquinolone resistance.

European registry on Helicobacter pylori management (Hp-EuReg) as a tool to evaluate and improve clinical practice in Moscow

Continuous evaluation of the actual clinical practice of diagnosis and treatment of Helicobacter pylori is crucial in order to provide the best standard of care and to compare health outcomes with expert recommendations. Aim:to evaluate the effectiveness of the standard triple therapy (amoxicillin, clarithromycin, a proton pump inhibitor) and the standard triple therapy plus bismuth tripotassium dicitrate. Materials and methods.Observational, prospective, multicenter study, carried out in one single Russian centre A.S. Loginov Moscow Clinical Scientific Center as part of the Hp-EuReg. Patients were included from 2013 to November 2019 by Russian gastroenterologists. Results.A total of 647 patients were collected and 330 were administered either standard triple therapy ((amoxicillin, clarithromycin, a proton pump inhibitor) or standard triple therapy plus bismuth tripotassium dicitrate. Invasive methods is dominates in the initial diagnosis of H. pylori: the frequency of use of the quick urease test decreased from 50% in 2013 to 31% in 2019. Serology was used in 27.9%. There has been an increase in the use of the13C-urea breath test from 13% in 2013 to 31% in 2019. The histological method (7.5%) and the stool antigen test (3.2%) were used less frequently. For eradication control non-invasive methods are mostly used:13C-UDT (82.7%) and the stool antigen test (14.4%). The effectiveness of standard triple therapy (mITT) was 68% with a 7-day course, 79% with a 10-day course, and 70% with a 14-day course. Combination of bismuth and standard triple therapy eradicates H. pylori (mITT) in 63%, 75% and 89%, respectively. Conclusion.An improvement in the clinical practice of managing patients with H. pylori infections has been noted. The standard triple therapy in combination with bismuth tripotassium dicitrate, prescribed for 14 days, is more effective.

Ten-Day Concomitant, 10-Day Sequential, and 7-Day Triple Therapy as First-Line Treatment for Helicobacter pylori Infection: A Nationwide Randomized Trial in Korea

Background/Aims

This nationwide, multicenter prospective randomized controlled trial aimed to compare the efficacy and safety of 10-day concomitant therapy (CT) and 10-day sequential therapy (ST) with 7-day clarithromycin-containing triple therapy (TT) as first-line treatment for Helicobacter pylori infection in the Korean population.

Methods

Patients with H. pylori infection were assigned randomly to 7d-TT (lansoprazole 30 mg, amoxicillin 1 g, and clarithromycin 500 mg twice daily for 7 days), 10d-ST (lansoprazole 30 mg and amoxicillin 1 g twice daily for the first 5 days, followed by lansoprazole 30 mg, clarithromycin 500 mg, and metronidazole 500 mg twice daily for the remaining 5 days), or 10d-CT (lansoprazole 30 mg, amoxicillin 1 g, clarithromycin 500 mg, and metronidazole 500 mg twice daily for 10 days). The primary endpoint was eradication rate by intention-to-treat (ITT) and per-protocol (PP) analyses.

Results

A total of 1,141 patients were included. The 10d-CT protocol achieved a markedly higher eradication rate than the 7d-TT protocol in both the ITT (81.2% vs 63.9%) and PP analyses (90.6% vs 71.4%). The eradication rate of the 10d-ST protocol was superior to that of the 7d-TT protocol (76.3% vs 63.9%, ITT analysis; 85.0% vs 71.4%, PP analysis). No significant differences in adherence or serious side effects were found among the three treatment arms.

Conclusions

The 10d-CT and 10d-ST regimens were superior to the 7d-TT regimen as standard first-line treatment in Korea.

Two-week bismuth-containing quadruple therapy and concomitant therapy are effective first-line treatments for Helicobacter pylori eradication: A prospective open-label randomized trial

BACKGROUND

Increasing levels of antibiotic resistance have reduced the Helicobacter pylori (H. pylori) eradication rates afforded by the standard triple therapy. Thus, 2-wk first-line four-drug regimens must be considered.

AIM

To analyze the eradication rates of modified bismuth-containing quadruple therapy (mBCQT) and concomitant therapy (CT), the associated adverse events, and compliance.

METHODS

Patients infected with H. pylori were prospectively randomized to receive mBCQT or CT for 2 wk. mBCQT featured a proton pump inhibitor (PPI), bismuth, metronidazole, and tetracycline, taken twice daily. CT included a PPI, clarithromycin, metronidazole, and amoxicillin, taken twice daily. The ¹³C-urea breath test was performed no earlier than 4 wk after therapy concluded to confirm eradication. If either the histological or rapid urease test was positive, H. pylori infection was diagnosed.

RESULTS

The demographic characteristics of 68 patients who received mBCQT and 68 who received CT did not differ significantly. On intention-to-treat analysis, the eradication rate was 88.2% (60/68) in the mBCQT group and 79.4% (54/68) in the CT group (P = 0.162). By per-protocol analysis, the respective eradication rates were 98.4% (60/61) and 93.1% (54/58) (P = 0.199). More CT than mBCQT patients experienced adverse events [33.8% (23/68) mBCQT vs 51.5% (35/58) CT patients, respectively, P = 0.037]. All patients showed good compliance [85.3% (58/68) mBCQT vs 82.4% (56/68) CT patients, P = 0.641].

CONCLUSION

The H. pylori eradication rates of the 2-wk mBCQT and CT regimens are high. Most patients show good compliance, and more CT than mBCQT patients experience adverse events.

Broad spectrum resistance in Helicobacter pylori isolated from gastric biopsies of patients with dyspepsia in Cameroon and efflux-mediated multiresistance detection in MDR isolates

Background

Antibiotic resistance is a leading cause of treatment failure in Helicobacter pylori infection. In Africa, there are very little data concerning the susceptibility of Helicobacter pylori isolates to antibiotics. The purpose of this study was to evaluate the resistance prevalence of Helicobacter pylori strains circulating in Cameroon, and to assess overexpression of efflux pump as a possible multi-drug resistance mechanisms.

Methods

A total of 140 H. pylori isolates were recovered from gastric biopsies of dyspeptic patients in two reference hospitals in Cameroon and analyzed for their antimicrobial susceptibility to amoxicillin, co-amoxiclav, ampicillin, penicillin, imipenem, metronidazole, rifabutin, erythromycin, clarithromycin, azithromycin, levofloxacin, ciprofloxacin, norfloxacin, tetracycline, doxycycline and minocycline. Antibiotic sensitivity was tested by disk diffusion method. Phe-Arg-naphthylamide (PAßN) was used as efflux pump inhibitor. INT broth microdilution method in supplemented Brain Heart Infusion broth was used to determine the MIC of ampicillin, amoxicillin, metronidazole, erythromycin, clarithromycin and doxycycline in the absence and the presence of PAßN against 32 selected MDR isolates.

Results

Overall H. pylori resistance rate was 100% to ampicillin, penicillin and co-amoxiclav; 97.14% to amoxicillin, 97.85% to metronidazole, 47.85% to erythromycin, 13.57% to clarithromycin; 5, 2.86 and 0.71% to doxycycline, tetracycline and minocycline respectively. No resistance to azithromycin, rifabutin, imipenem, ciprofloxacin, norfloxacin and levofloxacin was detected among H. pylori isolates. Seventy percent (70%) of the tested isolates elicited a multiple drugs resistance pattern; 42.57% double, 15.71% triple and 5.71% quadruple drugs resistance. Metronidazole and amoxicillin were more concerned with double resistance pattern (86.76%). The spectrum of activity recorded with metronidazole, doxycycline, clarithromycin and erythromycin ranged from 0 to 100% in the absence to the presence of PAßN against the tested MDR isolates. An 8 to 128-fold increase in potency was also noticed with these antibiotics in the presence of PAßN.

Conclusion

With regard to the high resistance rate to both amoxicillin and metronidazole, these drugs should be avoided as components of triple therapy in our milieu. In contrast, ciprofloxacin, norfloxacin, levofloxacin and tetracyclines could be used to achieve a better eradication rate and to reduce the risk of selection of H. pylori resistant strains.

Eradication rate of Helicobacter pylori reinfection in Korea: A retrospective study

BACKGROUND AND AIM

Guidelines for selecting the eradication regimen for Helicobacter pylori reinfection remain unclear. This study aimed to evaluate the eradication rate of H. pylori reinfection in patients with a previous infection successfully eradicated with index triple therapy.

METHODS

This was a single-center, retrospective case-control study. A total of 10 468 H. pylori-infected patients treated with proton-pump inhibitor-based triple eradication therapy at a tertiary medical institution between 2005 and 2016 were enrolled. We reviewed the medical records of the enrolled patients and compared the treatment outcomes in those with H. pylori reinfection after a successful eradication.

RESULTS

Helicobacter pylori infection was successfully eradicated with the index triple therapy in 7770 patients (74.2%). Among 3567 patients followed up for > 1 year, H. pylori reinfection occurred in 420 (11.8%; 3.06% per person-year) during a median follow-up of 39.1 months (interquartile range, 23.5-58.7 months). Of these patients, 164 received eradication therapy for reinfection (triple therapy in 102 and quadruple therapy in 62) and had follow-up data. Triple therapy showed an eradication rate of 78.4% for H. pylori reinfection, which was not significantly different from that of the index triple therapy (P = 0.394). Quadruple therapy for reinfection exhibited a better eradication rate (87.1%) than triple therapy but without statistical significance (P = 0.237).

CONCLUSIONS

Retreatment with triple therapy for H. pylori reinfection after successful eradication of prior infection showed comparable outcomes to the index triple therapy. Bismuth-containing quadruple therapy for reinfection tended to have a better eradication rate than did triple therapy.

Nationwide antibiotic resistance mapping of Helicobacter pylori in Korea: A prospective multicenter study

INTRODUCTION

The eradication rates for Helicobacter pylori have decreased in Korea although the prevalence of this bacterium has also decreased. Antibiotic resistance is likely to be a crucial factor in H. pylori eradication success, and we therefore mapped these resistance patterns nationwide in Korea.

MATERIALS AND METHODS

Five hundred and ninety adult subjects were prospectively enrolled from 2017 to 2018 from 15 centers across six geographic areas of Korea. A total of 580 biopsy tissues had been sampled from these patients during an upper endoscopy and were frozen at -80°C and delivered to a central laboratory. The agar dilution method was used to determine the minimum inhibitory concentration of amoxicillin, clarithromycin, metronidazole, tetracycline, ciprofloxacin, and levofloxacin for each H. pylori isolate.

RESULTS

The culture success rate was 60.2% (349/580). Resistance rates against clarithromycin, metronidazole, amoxicillin, tetracycline, levofloxacin, and ciprofloxacin were 17.8%, 29.5%, 9.5%, 0%, 37.0%, and 37.0%, respectively. The geographic distribution of metronidazole and quinolone resistance was highly variable. Some subjects had multiple H. pylori strains in the antrum and body of the stomach and showed a heterogeneous resistance profile between these anatomic areas. The H. pylori multidrug resistance (MDR) rate was 25.2% (88/349) among amoxicillin, clarithromycin, metronidazole, tetracycline, and quinolone and 11.2% (39/349) among four of these major antibiotics except for quinolone. The Seoul and Chungcheong areas showed a relatively lower MDR rate.

CONCLUSION

The antibiotic resistance of H. pylori differs by drug and geographic area in Korea. Detailed nationwide antibiotic resistance mapping is needed to develop an effective H. pylori eradication strategy.

Recognition of Helicobacter pylori by protein-targeting aptamers

BACKGROUND

Helicobacter pylori (H pylori) is a disease-causing pathogen capable of surviving under acidic conditions of the human stomach. Almost half of the world's population is infected with H pylori, with gastric cancer being the most unsatisfactory prognosis. Although H pylori has been discovered 30 years ago, the effective treatment and elimination of H pylori continue to be problematic.

MATERIALS AND METHODS

In our study, we screened nucleic acid aptamers using H pylori surface recombinant antigens as targets. Trypsin was used for separating aptamers that were bound to proteins. Following nine rounds of screening, we performed sequence similarity analyses to assess whether the aptamers can recognize the target protein. Two sequences with desirable recognition ability were selected for affinity detection. Aptamer Hp4 with the strongest binding ability to the H pylori surface recombinant antigen was chosen. After optimization of the binding conditions, we conducted specificity tests for Hp4 using Escherichia coli, Staphylococcus aureus, Vibrioanguillarum, and H pylori.

RESULTS

The data indicated that the aptamer Hp4 had an equilibrium dissociation constant (K_d ) of 26.48 ± 5.72 nmol/L to the target protein. This aptamer was capable of exclusively detecting H pylori cells, without displaying any specificity for other bacteria.

CONCLUSIONS

We obtained a high-affinity aptamer for H pylori, which is expected to serve as a new molecular probe for detection of H pylori.

Cost-effectiveness of a tailored Helicobacter pylori eradication strategy based on the presence of a 23S ribosomal RNA point mutation that causes clarithromycin resistance in Korean patients

BACKGROUND AND AIM

The Helicobacter pylori eradication rate using conventional triple therapy has decreased due to clarithromycin (CAM) resistance in H. pylori. Recently, dual priming oligonucleotide (DPO)-based multiplex polymerase chain reaction (PCR) can be used to detect H. pylori and point mutations in the 23S ribosomal RNA gene causing CAM resistance. This study aimed to evaluate the success rate and cost-effectiveness of tailored H. pylori eradication using DPO-PCR.

METHODS

The H. pylori-positive patients diagnosed by a rapid urease test or DPO-PCR were enrolled from a single academic hospital. The patients with positive rapid urease test results received a CAM-based triple regimen. In the tailored therapy group that underwent DPO-PCR testing, patients with A2142G and/or A2143G point mutations were treated with a bismuth-containing quadruple regimen. The cost-effectiveness of H. pylori eradication success was evaluated according to the average cost per patient and the incremental cost-effectiveness ratio.

RESULTS

A total of 243 patients were allocated to the triple therapy group and 124 patients to the tailored therapy group. The first-line eradication rate of H. pylori was significantly higher in the tailored therapy group than in the conventional triple therapy group (92.7% vs 76.5%, P < 0.001). The average costs per patient for tailored therapy were $307.37 and $299.59 for first-line and second-line treatments, respectively. Compared with triple therapy, the incremental cost-effectiveness ratios of tailored therapy were $3.96 and -$3.81 per patient for first-line and second-line treatments, respectively.

CONCLUSION

In Korea, tailored H. pylori eradication using DPO-PCR may be more cost-effective than conventional triple therapy.

Modified quadruple therapy versus bismuth-containing quadruple therapy in first-line treatment of Helicobacter pylori infection in Korea; rationale and design of an open-label, multicenter, randomized controlled trial

BACKGROUND

Clarithromycin-containing triple regimen for eradication of Helicobacter pylori is no longer acceptable in Korea due to high clarithromycin resistance. Concomitant therapy or bismuth-containing quadruple therapy is recommended as an alternative regimen. A recent study in Korea has shown that modified quadruple therapy has comparable efficacy and safety to concomitant therapy as a first-line regimen. However, there has been no comparative study of modified quadruple therapy with bismuth-containing quadruple therapy. The aim of this study is to compare the efficacy and safety of modified quadruple therapy with those of bismuth-containing quadruple therapy as a first-line regimen and to present the phenotypic and genotypic antibiotic resistance profile of H pylori.

METHODS

This study is an open-label, multicenter, randomized controlled trial. We are recruiting subjects endoscopically diagnosed with H pylori infection from 2 hospitals in Korea. Subjects will be randomly allocated either to modified quadruple therapy (proton-pump inhibitor bid, amoxicillin 1 g bid, metronidazole 500 mg tid, bismuth subcitrate 300 mg qid daily) or bismuth-containing quadruple therapy (proton-pump inhibitor bid, tetracycline 500 mg qid, metronidazole 500 mg tid, bismuth subcitrate 300 mg qid daily) for 14 days. The rate of eradication success and adverse events will be checked at least 4 weeks after the treatment. Antibiotic resistance will be established using both a bacterial culture with agar dilutions and DNA sequencing of the clarithromycin resistance point mutations in the 23S rRNA gene of H pylori.

CONCLUSION

The results of this study will provide solid evidence for determining the optimal treatment regimen for first-line H pylori eradication in Korea.

[The Efficacy of Bismuth-containing Quadruple Therapy after Moxifloxacin-based Sequential Therapy Failure in Helicobacter pylori Eradication]

Background/Aims

Moxifloxacin-based sequential therapy showed an excellent eradication rate as the first line treatment of Helicobacter pylori (H. pylori) infection. However, to the best of our knowledge, there were only a few studies on the treatment of those with failed moxifloxacin-based sequential therapy. Hence, this study was to investigate the efficacy of bismuth-containing quadruple therapy in those with failed moxifloxacin-based sequential or reverse sequential therapy for H. pylori eradication.

Methods

Between January 2013 and March 2016, we retrospectively analyzed patients who failed to eradicate H. pylori using moxifloxacin-based sequential (rabeprazole 20 mg bid and amoxicillin 1 g bid for 5-7 days, followed by rabeprazole 20 mg bid, metronidazole 500 mg bid, and moxifloxacin 400 mg qd for 5-7 days) and 10 days moxifloxacin-based reverse sequential therapy as the first line treatment. Then we investigated the eradication rates of bismuth-containing quadruple therapy as the second line treatment. All subjects had no history of H. pylori eradication before. Eradication rates were described as intention-to-treat (ITT) and per-protocol (PP) analyses. H. pylori status was evaluated by ¹³C-urea breath test 6 weeks after the end of the treatment. Moreover, we examined any side effects that caused discontinuation of therapy.

Results

Twenty-three patients received bismuth-containing quadruple therapy as the second line treatment. The overall eradication rates by ITT and PP analyses were 60.87% (n=14/23) and 73.68% (n=14/19). All the patients showed good compliance, and there were no serious adverse events.

Conclusions

Bismuth-containing quadruple therapy is insufficient as the second line eradication treatment after a failed attempt of moxifloxacin-based sequential or reverse sequential therapy. Large-scale clinical trials should be performed to establish better clinical evidence.

Pre-treatment with proton pump inhibitors decreases the success of primary Helicobacter pylori eradication using a vonoprazan-based regimen

Vonoprazan-based regimens have improved the rate of successful Helicobacter pylori (H. pylori) eradication, but it has not reached 100%. The aim of this study is to clarify significant predictors of successful H. pylori eradication using a vonoprazan-based regimen. In this retrospective cohort study, 174 patients who underwent primary H. pylori eradication therapy were included. All patients underwent esophagogastroduodenoscopy before treatment. The vonoprazan-based regimen includes amoxicillin 750 mg, clarithromycin 200 mg and vonoprazan 20 mg twice daily for one week. Pre-treatment with a proton pump inhibitor (PPI) was defined as continued PPI use for more than four weeks prior to eradication therapy. The rates of successful eradication were 83% (145/174) in intention-to-treat analysis and 85% (145/171) in per-protocol analysis. Predictors of successful eradication among 171 patients were evaluated in per-protocol analysis. In univariate analysis, male gender was a significant positive predictor of successful eradication (odds ratio [OR] 3.813, 95% confidence interval [CI] 1.363-10.663, p = 0.010) and pre-treatment with PPIs was a negative predictor (OR 0.193, 95%CI 0.076-0.485, p < 0.001). In multivariate analysis, male gender remained a positive predictor (OR 3.826, 95%CI 1.317-11.116, p = 0.013), and pre-treatment with PPIs (OR 0.232, 95%CI 0.087-0.615, p = 0.003) remained a negative predictor. In conclusion, pre-treatment with PPIs before eradication therapy decreases the rate of successful eradication. Therefore, it may be desirable to discontinue pre-treatment with PPIs prior to eradication therapy, because of the potential to improve the rate of successful eradication.

The effect of eradication of Helicobacter pylori on gastric cancer prevention in healthy asymptomatic populations

BACKGROUND

Although many epidemiologic studies have evaluated the effect of Helicobacter pylori eradication on gastric cancer, the effect is still uncertain in general populations. We evaluated whether H. pylori eradication would affect the incidence of gastric cancer in healthy asymptomatic populations.

MATERIALS AND METHODS

We performed a retrospective cohort study in 38 984 asymptomatic individuals, who underwent health screening examinations more than twice between 2005 and 2016. We investigated the incidence of gastric cancer among 3 groups: those without H. pylori infection (Hp-negative group), those with H. pylori eradication (eradication group), and those without H. pylori eradication (non-eradication group).

RESULTS

The cumulative incidence of gastric cancer was 54.5 cases per 100 000 person-years during a median of 6.4 years. In a multivariate analysis using the Cox proportional hazard model, the cumulative incidence of gastric cancer in the non-eradication group was significantly higher than those in the Hp-negative (hazard ratio [HR] 4.12, P < .001) and eradication groups (HR 2.73, P = .001). However, the cumulative incidence of gastric cancer was not significantly different between the eradication and Hp-negative groups. Other risk factors for gastric cancer occurrence were age, smoking, family history of gastric cancer, and gastric atrophy. The standardized incidence ratios of the age groups above 40 and below 70 in the eradication group were all significantly decreased.

CONCLUSIONS

Helicobacter pylori eradication reduced the cumulative incidence of gastric cancer in healthy asymptomatic population, and the effect of H. pylori eradication on the prevention of gastric cancer was observed in all ages.

The effect of virulence genotypes of Helicobacter pylori on eradication therapy in children

BACKGROUND/AIM

It is important to eradicate Helicobacter pylori at an early stage in patients during childhood to potentially prevent the development of H. pylori-related diseases. Studies have demonstrated that the virulence genotype of H. pylori influences the efficacy of eradication therapy. The efficacy of triple therapy has decreased significantly, which has seriously affected the clinical outcome of children with H. pylori infection. In this study we aimed to investigate the influence of virulence genotypes of H. pylori on triple eradication therapy in children.

PATIENTS AND METHODS

H. pylori strains were isolated from the gastric antrum mucosa in children with upper gastrointestinal symptoms. Polymerase chain reaction (PCR) was conducted to determine the H. pylori cagA, vacA, and iceA genotypes. All patients with H. pylori infection were administered 14-day triple therapy. After drug withdrawal for at least 4 weeks, the ¹³C-urea breath test (¹³C-UBT) was used to observe the therapeutic effect of H. pylori eradication. The eradication rates were evaluated by intention-to-treat (ITT) and per-protocol (PP) analyses.

RESULTS

A total of 107 patients were enrolled in this study. Nine patients were lost to follow-up, and 98 patients were administered eradication therapy. Based on ITT and PP analyses, the H. pylori eradication rate was 64.5% (69/107) and 70.4% (69/98), respectively. Among the successful eradication groups, the cagA-positive, vacA s1a, vacA s1c, vacA m1, vacA m2, iceA 1, and iceA 2 genes were identified in 72.8%, 68.1%, 76.9%, 60.0%, 74.6%, 71.8%, and 75.0% of strains, respectively. Of the unsuccessful eradication groups, the cagA-positive, vacA s1a, vacA s1c, vacA m1, vacA m2, iceA 1, and iceA 2 genes were identified in 27.2%, 31.9%, 23.1%, 40.0%, 25.4%, 28.2%, and 25.0% of strains, respectively. No statistically significant differences were noted in the detection rate of the H. pylori genotypes between the H. pylori successful and unsuccessful eradication groups (P > 0.05).

CONCLUSIONS

The cagA, vacA, and iceA genotypes of H. pylori are not associated with the efficacy of omeprazole-based triple therapy on the eradication of H. pylori infection in children.

Concomitant, sequential, and 7-day triple therapy in first-line treatment of Helicobacter pylori infection in Korea: study protocol for a randomized controlled trial

Background

Most international guidelines recommend triple-therapy regimens consisting of a proton pump inhibitor, clarithromycin, and amoxicillin/metronidazole for at least 7 days for the eradication of Helicobacter pylori. However, the efficacy of 7-day clarithromycin-based standard triple therapy for H. pylori infection is currently unacceptable in Korea. In this study, we will compare the efficacy and safety of 7-day standard triple therapy, 10-day sequential therapy, and 10-day concomitant therapy for the first-line treatment of H. pylori infection in Korea.

Methods/design

In this multicenter, investigator-blinded, randomized trial we are recruiting adult patients with H. pylori infection from 15 hospitals in Korea to determine whether sequential or concomitant treatment is superior to standard triple therapy. Patients are randomly assigned to receive either standard triple therapy (lansoprazole, amoxicillin, and clarithromycin) for 7 days, or sequential treatment (lansoprazole and amoxicillin for the first 5 days, followed by lansoprazole, clarithromycin, and metronidazole for another 5 days) for 10 days, or concomitant therapy (lansoprazole, amoxicillin, clarithromycin, and metronidazole) for 10 days. The primary outcome is the rate of H. pylori eradication in the intention-to-treat population.

Discussion

The results of this study will be crucial for determining the optimal regimen for the primary treatment of H. pylori infection in Korea. This study will produce vital evidence that will lead to revisions to guidelines concerning first-line treatment regimens for H. pylori infection.

Trial registration

Clinical Research Information Service (CRIS), Republic of Korea, KCT0001980. Registered on 25 July 2016.

Electronic supplementary material

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Efficacy of Levofloxacin-Based Third-Line Therapy for the Eradication of Helicobacter pylori in Peptic Ulcer Disease

Background/Aims

The resistance rate of Helicobacter pylori is gradually increasing. We aimed to evaluate the efficacy of levofloxacin-based third-line H. pylori eradication in peptic ulcer disease.

Methods

Between 2002 and 2014, 110 patients in 14 medical centers received levofloxacin-based third-line H. pylori eradication therapy for peptic ulcer disease. Of these, 88 were included in the study; 21 were excluded because of lack of follow-up and one was excluded for poor compliance. Their eradication rates, treatment regimens and durations, and types of peptic ulcers were analyzed.

Results

The overall eradiation rate was 71.6%. The adherence rate was 80.0%. All except one received a proton-pump inhibitor, amoxicillin, and levofloxacin. One received a proton-pump inhibitor, amoxicillin, levofloxacin, and clarithromycin, and the eradication was successful. Thirty-one were administered the therapy for 7 days, 25 for 10 days, and 32 for 14 days. No significant differences were observed in the eradication rates between the three groups (7-days, 80.6% vs 10-days, 64.0% vs 14-days, 68.8%, p=0.353). Additionally, no differences were found in the eradiation rates according to the type of peptic ulcer (gastric ulcer, 73.2% vs duodenal/gastroduodenal ulcer, 68.8%, p=0.655).

Conclusions

Levofloxacin-based third-line H. pylori eradication showed efficacy similar to that of previously reported first/second-line therapies.

[The Efficacy of Moxifloxacin-containing Triple Therapy after Hybrid Therapy Failure in Helicobacter pylori Eradication]

Background/Aims

Hybrid therapy was successful in eradicating Helicobacter pylori (H. pylori) according to previous reports. However, to the best of our knowledge, there have only been a few studies evaluating the optimal choice after hybrid failure. Hence, we aimed to evaluate the efficacy of moxifloxacin-containing triple therapy after hybrid therapy failure in H. pylori eradication.

Methods

Between January 2013 and March 2016, we retrospectively reviewed patients who underwent failed hybrid therapy, as first line treatment, in eradicating H. pylori (rabeprazole and amoxicillin b.i.d for 14 days, in addition to clarithromycin and metronidazole b.i.d for final 7 days). Then, we investigated the eradication rates of moxifloxacin-containing triple therapy (rabeprazole, amoxicillin b.i.d and moxifloxacin qd) as the second line of treatment. Intention-to-treat (ITT) and per-protocol (PP) analyses were used to determine the eradication rate. We evaluated the status of H. pylori by using ¹³C-urea breath test 6 weeks after the final treatment. Moreover, compliance and adverse effects of each patient were analyzed.

Results

Among those who failed the initial hybrid therapy, 11 patients received moxifloxacin-containing triple therapy. The overall eradication rates, as determined by ITT and PP, were 72.7% (n=8/11) and 80% (n=8/10), respectively. The compliance rate was 100%, and there were no serious adverse effects.

Conclusions

Moxifloxacin-containing triple therapy can be used as a second line therapy in case of hybrid therapy failure. A large scale study is necessary to confirm the findings of this study and establish clinical evidence.

Efficacy of Helicobacter pylori eradication therapies in Korea: A systematic review and network meta-analysis

BACKGROUND

The efficacy of Helicobacter pylori eradication regimens may depend on the country where the studies were performed because of the difference in antibiotic resistance. We aimed to analyze the efficacy of H. pylori eradication regimens in Korea where clarithromycin resistance rate is high.

METHODS

We searched for all relevant randomized controlled trials published until November 2016 that investigated the efficacy of H. pylori eradication therapies in Korea. A network meta-analysis was performed to calculate the direct and indirect estimates of efficacy among the eradication regimens.

RESULTS

Forty-three studies were identified through a systematic review, of which 34 studies, published since 2005, were included in the meta-analysis. Among 21 included regimens, quinolone-containing sequential therapy for 14 days (ST-Q-14) showed the highest eradication rate (91.4% [95% confidence interval [CI], 86.9%-94.4%] in the intention-to-treat [ITT] analysis). The eradication rate of the conventional triple therapy for 7 days, standard sequential therapy for 10 days, hybrid therapy for 10-14 days, and concomitant therapy for 10-14 days was 71.1% (95% CI, 68.3%-73.7%), 76.2% (95% CI, 72.8%-79.3%), 79.4% (95% CI, 75.5%-82.8%), and 78.3% (95% CI, 75.3%-80.9%), respectively, in the ITT analysis. In the network meta-analysis, ST-Q-14 showed a better comparative efficacy than the conventional triple therapy, standard sequential therapy, hybrid therapy, and concomitant therapy. In addition, tolerability of ST-Q-14 was comparable to those regimens.

CONCLUSION

In Korea, ST-Q-14 showed the highest efficacy in terms of eradication and a comparable tolerability, compared to the results reported for the conventional triple therapy, standard sequential therapy, hybrid therapy, and concomitant therapy.

Sequential Therapy versus Triple Therapy for the First Line Treatment of Helicobacter pylori in Korea: A Nationwide Randomized Trial

Background/Aims

Eradication of Helicobacter pylori infection with standard triple therapy (TT) has declined primarily because of increased antibiotic resistance. Sequential therapy (ST) has been suggested as an alternative to TT for the first-line treatment of H. pylori. The purpose of this study was to compare the efficacy of ST with TT.

Methods

This was a multicenter, randomized open-label trial performed at nine centers in Korea. Patients with H. pylori infection were randomly assigned to receive either 7 day TT or 10 day ST. Eradication rates, drug compliance, and adverse events were compared among the two regimens.

Results

A total of 601 patients were enrolled between March 2011 and September 2014. The intention-to-treat eradication rates were 70.8% for TT and 82.4% for ST (p=0.001). The corresponding per protocol eradication rates were 76.9% and 88.8% for TT and ST, respectively (p=0.000). There were no statistically significant differences between the two regimens with respect to drug compliance and adverse events.

Conclusions

ST achieved better eradication rates than TT as a first-line therapy for H. pylori eradication in Korea.

Optimal First-Line Treatment for Helicobacter pylori Infection: Recent Strategies

A new treatment strategy is needed, as the efficacy of triple therapy containing clarithromycin—the current standard treatment for Helicobacter pylori infection—is declining. Increasing antibiotic resistance of H. pylori is the most significant factor contributing to eradication failure. Thus, selecting the most appropriate regimen depending on resistance is optimal, but identifying resistance to specific antibiotics is clinically challenging. In a region suspected to have high clarithromycin resistance, bismuth quadruple therapy and so-called nonbismuth quadruple therapies (sequential, concomitant, and sequential-concomitant hybrid) are some first-line regimen options. However, more research is needed regarding appropriate second-line treatments after first-line treatment failure. Tailored therapy, which is based on antibiotic sensitivity testing, would be optimal but has several limitations for clinical use, and an alternative technique is required. A novel potassium-competitive acid blocker-based eradication regimen could be a valuable eradication option in the near future.

Online Registry for Nationwide Database of Current Trend of Helicobacter pylori Eradication in Korea: Interim Analysis

Eradication of Helicobacter pylori using first-line therapy is becoming less effective. Subjects who had been treated for H. pylori infection were prospectively enrolled through an on-line database registry from October 2010 to December 2012. Demographic data, detection methods, treatment indication, regimens, durations, compliance, adverse events, and eradication results for H. pylori infection were collected. Data of 3,700 patients from 34 hospitals were analyzed. The overall eradication rate of the first-line therapy was 73.0%. Eradication failure was significantly associated with old age, concomitant medication, and comorbidity. Regional differences in eradication rates were observed. The most common first-line therapy was proton pump inhibitor-based triple therapy (standard triple therapy, STT) for 7 days (86.8%). The eradication rates varied with regimens, being 73% in STT, 81.8% in bismuth-based quadruple therapy, 100% in sequential therapy, and 90.3% in concomitant therapy. The eradication rate in treatment-naïve patients was higher than that in patients previously treated for H. pylori infection (73.8% vs. 58.5%, P < 0.001). The overall eradication rate for second-line therapy was 84.3%. There was no statistical difference in eradication rates among various regimens. H. pylori eradication rate using STT is decreasing in Korea and has become sub-optimal, suggesting the need for alternative regimens to improve the efficacy of first-line therapy for H. pylori infection.

High Dose Ilaprazole/Amoxicillin as First-Line Regimen for Helicobacter pylori Infection in Korea

Objective. The eradication rate of Helicobacter pylori (H. pylori) following standard triple therapy has declined over the past few decades. This study has determined whether high dose dual therapy (PPI and amoxicillin) is adequate for eradicating H. pylori in Korea. Methods. This was an open-labeled study of H. pylori infected treatment-naive patients. Subjects received dual therapy for 14 days: ilaprazole 40 mg tablets given twice a day and amoxicillin 750 mg tablets given 4 times a day. At the end of the therapy, the subjects visited the clinic to confirm compliance and monitor for any side effects. Subjects visited again after 4–6 weeks to confirm H. pylori status through a urea breath test. Results. The cure rate of H. pylori was 79.3% (23 of 29) (95% confidence interval: 61.6–90.2) in the intention-to-treat analysis and 82.1% (23 of 28) in the per-protocol analysis. Compliance rates were high (96.6%) and side effects were minimal and tolerable. Conclusion. A high dose of ilaprazole + amoxicillin was ineffective as the first-line therapy for eradicating H. pylori in Korea. Future studies should focus on intragastric pH measurements and assess amoxicillin resistance.