Adverse events with bismuth salts for Helicobacter pylori eradication: Systematic review and meta-analysis

Allosteric Regulation and Inhibition of Coronavirus 3CLpro Revealed by HDX-MS

Coronavirus (CoV) infections have caused contagious and fatal respiratory diseases in humans worldwide. CoV 3-chymotrypsin-like proteases (3CLpro or Mpro) play an important role in viral maturation, and maintenance of their dimeric conformation is crucial for viral activity. Therefore, allosterically regulated dimerization of 3CLpro can be employed as a drug development target. Here, we investigated the allosteric regulatory mechanism of 3CLpro dimerization by using hydrogen/deuterium exchange coupled with mass spectrometry (HDX-MS) technology. We found that the FLAG tag directly coupled to the N-finger of 3CLpro significantly increased HDX kinetics at the dimer interface, and 3CLpro transformed from a dimer to a monomer. The 3CLpro mutants of SARS-CoV-2, which are monomeric, also exhibited increased deuterium exchange. Binding of the allosteric inhibitor Gastrodenol to most betacoronavirus 3CLpros led to increased allosteric deuterium exchange, resulting in the monomeric conformation of the CoV 3CLpro upon binding. Molecular dynamics (MD) simulation analysis further indicated the molecular mechanism of action of Gastrodenol on CoV 3CLpro: binding of Gastrodenol to SARS-CoV-2 3CLpro destroyed the hydrogen bond in the dimer interface. These results suggest that Gastrodenol may be a potential broad-spectrum anti-betacoronavirus drug.

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.

Pharmacokinetic and Safety Study of Bismuth Potassium Citrate Formulations in Healthy Subjects

BACKGROUND

Potassium bismuth citrate is a gastric mucosal protector and a key drug for treating peptic ulcers.

OBJECTIVE

To evaluate the pharmacokinetic characteristics and safety of 120-mg bismuth potassium citrate formulations administered orally under fasting conditions in healthy Chinese subjects.

METHOD

A single-center open two-cycle trial was conducted on 12 healthy subjects who received a single oral dose of 120 mg of bismuth potassium citrate. The plasma concentration of bismuth was determined using a validated inductively coupled plasma mass spectrometry (ICP‒MS) method. The pharmacokinetic parameters, including maximum serum concentration (Cmax) and area under the curve concentration-time curve (AUC0-t and AUC0-∞), and safety were evaluated via noncompartment analysis.

RESULTS

The ratios of the least square geometric mean ratio between the test (T) and reference (R) formulations for Cmax, AUC0-t, and AUC0-∞ were 44.8%, 55.5%, and 64.4%, respectively; the bilateral 95% confidence intervals (Cis) for these parameters were 20.2-99.6%, 24.1-127.5%, and 23.7-175.0%, respectively, and the non-inferior limits for these parameters were 169.4%, 198.8%, and 200.5%, respectively. The upper limits of the one-sided 97.5% confidence interval for the least squares geometric mean ratio (T/R) were lower than the non-inferior limits. No serious adverse reactions or adverse reactions leading to detachment were observed among the subjects.

CONCLUSION

The concentration of bismuth in the blood of healthy subjects in the T formulation was not greater than that in the R formulation. Similarly, the safety of oral administration of 120 mg of bismuth potassium citrate formulations to healthy subjects was good. The trial registration number (TRN) was [2018] 013, 6 December 2018.

Pharmacokinetics, Safety, and Tolerability of Vonoprazan- or Esomeprazole-Based Bismuth-Containing Quadruple Therapy: A Phase 1, Double-Blind, Parallel-Group Study in Adults with Helicobacter pylori Infection in China

Quadruple therapy comprising 2 antibiotics, a proton pump inhibitor, and bismuth, is recommended for Helicobacter pylori eradication in China. This Phase 1, double-blind, parallel-group study aimed to evaluate the pharmacokinetics, safety, and tolerability of bismuth-containing vonoprazan- or esomeprazole-based quadruple therapy in H. pylori-positive healthy subjects at a single site in China. Quadruple therapy comprising vonoprazan 20 mg or esomeprazole 20 mg with bismuth potassium citrate 600 mg (equivalent to bismuth 220 mg), clarithromycin 500 mg, and amoxicillin 1000 mg was administered twice daily for 2 weeks. Forty-four subjects were enrolled, 22 each in the vonoprazan (mean age, 34.5 years; men, 63.6%) and esomeprazole (mean age, 31.6 years; men, 59.1%) groups. Day 14 bismuth plasma pharmacokinetic parameters area under the plasma concentration-time curve during a dosing interval (geometric mean ratio, 1.07 [90% confidence interval, 0.82-1.40]) and maximum observed plasma concentration (geometric mean ratio, 1.30 [90% confidence interval, 0.94-1.81]) were similar between the treatment groups. At Day 42 follow-up, 100% and 94.4% of subjects were H. pylori negative in the vonoprazan and esomeprazole groups, respectively. The incidence of treatment-emergent adverse events was similar between the groups, with no serious adverse events. No new safety concerns were identified. In conclusion, vonoprazan had no significant effect on plasma bismuth exposure compared with esomeprazole.

Ilaprazole-amoxicillin dual therapy at high dose as a first-line treatment for helicobacter pylori infection in Hainan: a single-center, open-label, noninferiority, randomized controlled trial

OBJECTIVES

This study aimed to evaluate the efficacy, adverse events, patient compliance, and cost of dual therapy with Ilaprazole-amoxicillin (IA) at high dose versus Ilaprazole-amoxicillin-furazolidone-bismuth (IAFB) quadruple therapy for the Helicobacter pylori (H.pylori) infection among Chinese patients.

METHODS

200 patients who had tested positive for H. pylori and undergoing upper gastrointestinal endoscopy after being diagnosed with chronic gastritis participated in this open-label randomized controlled clinical trial. Patients were randomized to Group A and Group B: the 14-day IA dual treatment group (101) and IAFB quadruple treatment group (99). The ¹³ C urea breath test was conducted to determine whether H. pylori had been eliminated 4-6 weeks after the treatment. Eradication rates, drug-related adverse events, patient compliance, and drug costs were compared between the two treatment groups.

RESULTS

Eradication rates in group A were 92.1% and 94.9%, depending on the intention-to-treat (ITT), per-protocol (PP), respectively, which was similar to group B (91.9% and 93.6%). There was no significant difference observed in adverse events between the two groups (P = 0.518). Interestingly, compliance was significantly higher in group A compared to the group B (P = 0.031). In addition, drug costs were significantly lower for group A in comparison to the group B.

CONCLUSIONS

IA dual therapy was found to be equally effective, safer and less costly than IAFB quadruple therapy. Therefore, these therapies can be potentially considered as first-line regimens for empirical treatment.

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.

Factors associated with treatment failure, and possible applications of probiotic bacteria in the arsenal against Helicobacter pylori

INTRODUCTION

Helicobacter pylori is a widespread helical Gram-negative bacterium, which causes a variety of stomach disorders, such as peptic ulcer, chronic atrophic gastritis, and gastric cancer. This microbe frequently colonizes the mucosal layer of the human stomach and survives in the inhospitable microenvironment, by adapting to this hostile milieu.

AREAS COVERED

In this extensive review, we describe conventional antibiotic treatment regimens used against H. pylori including, empirical, tailored, and salvage therapies. Then, we present state-of-the-art information about reasons for treatment failure against H. pylori. Afterward, the latest advances in the use of probiotic bacteria against H. pylori infection are discussed. Finally, we propose a polymeric bio-platform to provide efficient delivery of probiotics for H. pylori infection.

EXPERT OPINION

For effective probiotic delivery systems, it is necessary to avoid the early release of probiotics at the acidic stomach pH, to protect them against enzymes and antimicrobials, and precisely target H. pylori bacteria which have colonized the antrum area of the stomach (basic pH).

Helicobacter pylori infection

Helicobacter pylori infection causes chronic gastritis, which can progress to severe gastroduodenal pathologies, including peptic ulcer, gastric cancer and gastric mucosa-associated lymphoid tissue lymphoma. H. pylori is usually transmitted in childhood and persists for life if untreated. The infection affects around half of the population in the world but prevalence varies according to location and sanitation standards. H. pylori has unique properties to colonize gastric epithelium in an acidic environment. The pathophysiology of H. pylori infection is dependent on complex bacterial virulence mechanisms and their interaction with the host immune system and environmental factors, resulting in distinct gastritis phenotypes that determine possible progression to different gastroduodenal pathologies. The causative role of H. pylori infection in gastric cancer development presents the opportunity for preventive screen-and-treat strategies. Invasive, endoscopy-based and non-invasive methods, including breath, stool and serological tests, are used in the diagnosis of H. pylori infection. Their use depends on the specific individual patient history and local availability. H. pylori treatment consists of a strong acid suppressant in various combinations with antibiotics and/or bismuth. The dramatic increase in resistance to key antibiotics used in H. pylori eradication demands antibiotic susceptibility testing, surveillance of resistance and antibiotic stewardship.

The benefit of the bismuth add-on to the 2-week clarithromycin-based triple regimen for Helicobacter pylori eradication: a propensity score-matched retrospective study

BACKGROUND

Bismuth salt is bacteriostatic and bactericidal against Helicobacter pylori (H. pylori). Little is known about the benefit of bismuth itself. Recently in Korea, government regulation changed to allow bismuth add-on to conventional triple eradication regimens. Study aimed the additional benefit of the bismuth add-on to the 2-week clarithromycin-based triple regimen for H. pylori eradication.

METHODS

A single-centered retrospective review of electronic medical records was conducted in Seoul, Korea. Treatment-naïve H. pylori infected subjects treated with the clarithromycin-based triple regimen were consecutively enrolled. After propensity score matching, 118 subjects who were treated with rabeprazole 20 mg, amoxicillin 1 g, and clarithromycin 500 mg twice daily for 14 days (PAC) and matched 118 subjects with PAC plus bismuth subcitrate potassium 300 mg twice daily for 14 days (PACB) were included in the final analysis. The primary endpoint was the eradication success rates in each group.Article title: Kindly check and confirm the edit made in the article title.Yes, I agree with the article title.  RESULTS: The eradication success rates were 91.5% (86.4-96.6%) for PACB regimen and 81.4% (74.2-88.5%) for PAC in the intention-to-treat analysis, and 97.3% (94.2-100%) for PACB and 88.1% (81.9-94.3%) for PAC in the per-protocol analysis. The relative risk of eradication failure for PACB over PAC was calculated as 0.184 (0.0492-0688, p value = 0.005) in multiple regression logistic analysis. Compliance and adverse event incidence were not different between the two groups.Author names: Please confirm if the author names are presented accurately and in the correct sequence (given name, middle name/initial, family name). Author 1 Given name: [Da Wit], Last name: [Shin]. Author 2 Given name: [Dae Young], Last name: [Cheung]. Author 3 Given name: [Ji Hee], Last name: [Song]. Author 4 Given name: [Fan Hee], Last name: [Lee]. Author 5 Given name: [Jin Il], Last name: [Kim]. Yes. I found the names presented are accurate and in the correct sequence. Author 1 Given name: [Da Wit], Last name: [Shin].Author 2 Given name: [Dae Young], Last name: [Cheung].Author 3 Given name: [Ji Hee], Last name: [Song].Author 6 Given name: [Han Hee], Last name: [Lee].Author 7 Given name: [Jin Il], Last name: [Kim].

CONCLUSION

The bismuth add-on to the 2-week clarithromycin-based triple regimen increased the eradication success rate.

Focusing on Helicobacter pylori infection in the elderly

As a confirmed carcinogen, Helicobacter pylori (H. pylori) is the main cause of inflammatory diseases of the upper digestive tract and even gastric cancer. There is a high prevalence of H. pylori infection among the elderly population, which may cause adverse clinical outcomes. Particularly noteworthy is that guidelines or expert consensus presently available on H. pylori infection overlook the management of the elderly population as a special group. A brief overview of H. pylori in the elderly is as follows. The detection of H. pylori infection can be divided into invasive and non-invasive techniques, and each technique has its advantages and shortcomings. There may be more side effects associated with eradication treatment in elderly individuals, especially for the frail population. Physical conditions and risk-benefit assessments of the elderly should be considered when selecting therapeutic strategies for H. pylori eradication. Unless there are competing factors, elderly patients should receive H. pylori eradication regimens to finally reduce the formation of gastric cancer. In this review, we summarize the latest understanding of H. pylori in the elderly population to provide effective managements and treatment measures.

Biological Characteristics of Polyurethane-Based Bone-Replacement Materials

A study is presented on four polymers of the polyurethane family, obtained using a two-stage process. The first composition is the basic polymer; the others differ from it by the presence of a variety of fillers, introduced to provide radiopacity. The fillers used were 15% bismuth oxide (Composition 2), 15% tantalum pentoxide (Composition 3), or 15% zirconium oxide (Composition 4). Using a test culture of human fibroblasts enabled the level of cytotoxicity of the compositions to be determined by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay, along with variations in the characteristics of the cells resulting from their culture directly on the specimens. The condition of cells on the surfaces of the specimens was assessed using fluorescence microscopy. It was shown that introducing 15% bismuth, tantalum, or zinc compounds as fillers produced a range of effects on the biological characteristics of the compositions. With the different fillers, the levels of toxicity differed and the cells' proliferative activity or adhesion was affected. However, in general, all the studied compositions may be considered cytocompatible in respect of their biological characteristics and are promising for further development as bases for bone-substituting materials. The results obtained also open up prospects for further investigations of polyurethane compounds.

Management of Helicobacter pylori infection: the Maastricht VI/Florence consensus report

Helicobacter pyloriInfection is formally recognised as an infectious disease, an entity that is now included in the International Classification of Diseases 11th Revision. This in principle leads to the recommendation that all infected patients should receive treatment. In the context of the wide clinical spectrum associated with Helicobacter pylori gastritis, specific issues persist and require regular updates for optimised management.The identification of distinct clinical scenarios, proper testing and adoption of effective strategies for prevention of gastric cancer and other complications are addressed. H. pylori treatment is challenged by the continuously rising antibiotic resistance and demands for susceptibility testing with consideration of novel molecular technologies and careful selection of first line and rescue therapies. The role of H. pylori and antibiotic therapies and their impact on the gut microbiota are also considered.Progress made in the management of H. pylori infection is covered in the present sixth edition of the Maastricht/Florence 2021 Consensus Report, key aspects related to the clinical role of H. pylori infection were re-evaluated and updated. Forty-one experts from 29 countries representing a global community, examined the new data related to H. pylori infection in five working groups: (1) indications/associations, (2) diagnosis, (3) treatment, (4) prevention/gastric cancer and (5) H. pylori and the gut microbiota. The results of the individual working groups were presented for a final consensus voting that included all participants. Recommendations are provided on the basis of the best available evidence and relevance to the management of H. pylori infection in various clinical fields.

Impact of insufficient doses of medications on Helicobacter pylori eradication: a retrospective observational study

BACKGROUND AND AIMS

The doses of medications may influence the success of Helicobacter pylori (H. pylori) eradication. This real-world observational study aimed to explore the impact of insufficient doses of medications prescribed for the bismuth-containing quadruple therapy (BQT) regimen on successful H. pylori eradication.

METHODS

We retrospectively screened the patients who were diagnosed with H. pylori infection and received BQT regimens for H. pylori eradication at our department between January 2017 and July 2020. The rate of successful H. pylori eradication was compared according to the doses of medications prescribed. Standard doses were defined according to the clinical guidelines.

RESULTS

Overall, 1054 patients were included. The rate of successful H. pylori eradication was 78.2% (824/1054). Among them, proton pump inhibitors (PPIs) and antibiotics were prescribed at insufficient doses in 37.0% (390/1054) and 6.7% (71/1054) of patients, respectively. Furthermore, pantoprazole (98.7% [385/390]) was the most common type of PPIs prescribed at insufficient doses, and nitroimidazoles (85.9% [61/71]) were the most common type of antibiotics prescribed at insufficient doses. Among the patients receiving colloidal bismuth pectin (CBP) (200mg tid) and standard-dose antibiotics, the rate of successful H. pylori eradication was lower in insufficient-dose PPIs group than standard-dose PPIs group (78.1% [271/347] versus 82.6% [438/530], P=0.095). Among the patients receiving CBP (200mg tid) and standard-dose PPIs, the rate of successful H. pylori eradication was significantly lower in insufficient-dose antibiotics group than standard-dose antibiotics group (37.8% [14/37] versus 82.6% [438/530], P<0.0001). Among the patients receiving CBP 200mg tid, the rate of successful H. pylori eradication was significantly lower in patients receiving both PPIs and antibiotics at insufficient doses than those at standard doses (46.4% [13/28] versus 82.6% [438/530], P<0.0001).

CONCLUSION

Among the BQT regimens, PPIs and/or antibiotics, especially pantoprazole and metronidazole, are often prescribed at insufficient doses, compromising the success of H. pylori eradication.

Randomised clinical trial: comparison of efficacy and adverse effects of a standard triple clarithromycin-containing regimen with high-dose amoxicillin and bismuth therapy in Helicobacter pylori eradication

BACKGROUND

The clarithromycin-based triple therapy is the most prescribed Helicobacter pylori eradication regimen in Europe; it causes adverse effects in a significant proportion of subjects, leading to discontinuation. Alternative therapies are required because of increasing clarithromycin resistance or to decrease the adverse effects.

AIMS

We compared the efficacy and spectrum of adverse effects of clarithromycin-based triple therapy with the high-dose amoxicillin/bismuth regimen.

METHODS

A randomised clinical trial enrolled healthy individuals aged 40-64 years. H. pylori was assessed with a 13C-urea breath test. In total 579 H. pylori-positive subjects were randomly allocated in two groups: group 1: clarithromycin 500 mg, amoxicillin 1000 mg, esomeprazole 40 mg, all twice daily; group 2: bismuth subcitrate 240 mg twice daily, amoxicillin 1000 mg three times daily, esomeprazole 40 mg twice daily. Regimens were administered for 14 days.Information on treatment completion and adverse effects were collected via a telephone interview at 21-28 days after medication delivery. The efficacy was assessed by UBT 6 months after the treatment.

RESULTS

We analysed 483 subjects for adverse effects (248 vs. 235 respectively). Furthermore, 316 subjects were analysed for efficacy. In per-protocol analysis, a higher efficacy was seen in group 1 (88.4 vs. 77.0%; P < 0.001); no difference was observed in compliance (90.3 and 91.2%). Therapy-related adverse effects were more common in group 1 (56.9 vs. 40.0%; P < 0.01). In intention-to-treat analysis no statistical difference in efficacy was revealed.

CONCLUSIONS

Bismuth-based high-dose amoxicillin therapy showed a lower efficacy but was less frequently associated with adverse effects. Further research is required to examine the high-dose amoxicillin and bismuth-containing regimens in various populations to maximise eradication efficacy.

Epithelial protective therapy in comorbid diseases. Practical Guidelines for Physicians

In 2021 the first multidisciplinary National Consensus on the pathophysiological and clinical aspects of Increased Epithelial Permeability Syndrome was published. The proposed guidelines are developed on the basis of this Consensus, by the same team of experts. Twenty-eight Practical Guidelines for Physicians statements were adopted by the Expert Council using the "delphic" method. Such main groups of epithelial protective drugs as proton pump inhibitors, bismuth drugs and probiotics are discussed in these Guidelines from the positions of evidence-based medicine. The clinical and pharmacological characteristics of such a universal epithelial protector as rebamipide, acting at the preepithelial, epithelial and subepithelial levels, throughout gastrointestinal tract, are presented in detail.

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.

Orally administered bismuth drug together with N-acetyl cysteine as a broad-spectrum anti-coronavirus cocktail therapy

A cocktail therapy comprising bismuth drugs and N-acetyl-l-cysteine is reported to suppress the replication of SARS-CoV-2 via the oral route. The broad-spectrum inhibitory activities of the combination upon key viral cysteine enzymes are verified.

The efficacy and safety of different bismuth agents in Helicobacter pylori first-line eradication: A multicenter, randomized, controlled clinical trial

BACKGROUND

The aim of this study was to evaluate the efficacy and safety of bismuth pectin capsules and bismuth pectin granules in the first-line quadruple treatment of Helicobacter pylori (H. pylori).

METHODS

This study was a multicenter, randomized, open-labelled controlled clinical trial. Patients with a H. pylori infection were randomized into 4 groups (1:1:1:1) and treated with a 14-day bismuth-containing quadruple therapy. The 4 groups received either bismuth potassium citrate capsules (220 mg), colloidal bismuth pectin capsules (200 mg), bismuth pectin granules (150 mg), or bismuth pectin granules (300 mg). The primary outcome was the eradication rate of H. pylori. The secondary outcomes included symptom improvement, patient compliance, and incidence of adverse events. This study was registered at ClinicalTrials.gov (NCT04209933).

RESULTS

A total of 240 patients were included in this study, and 211 patients completed the follow-up. An intention-to-treat analysis showed that the H. pylori eradication rates of the 4 groups were 73.3%, 76.7%, 75.0%, and 71.7%, respectively. The per-protocol analysis showed that the H. pylori eradication rates of the 4 groups were 86.3%, 82.1%, 83.3%, and 86.0%. There was no significant difference among the 4 groups in the H. pylori eradication rate (P > .05). There were also no significant differences in the symptom improvement rate, overall adverse reaction rate, or patient compliance among the 4 groups.

CONCLUSIONS

Bismuth pectin capsules and bismuth pectin granules had similar efficacy and safety for H. pylori eradication compared to bismuth potassium citrate. These data suggest that bismuth pectin can be an alternative to bismuth potassium citrate to eradicate H. pylori when using bismuth-containing quadruple therapy.

In vitro evaluation of the antibacterial effect of colloidal bismuth subcitrate on Porphyromonas gingivalis and its biofilm

OBJECTIVE

To investigate the antibacterial and anti-biofilm effects of colloidal bismuth subcitrate (CBS) on Porphyromonas gingivalis (P. gingivalis) in its planktonic and biofilm forms and also compare it with that of 0.2% chlorhexidine (CHX).

DESIGN

The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of CBS were determined by the microdilution method; the bacteriostatic rate of CBS was determined by the MTT assay; the effect of CBS on the membrane integrity of P. gingivalis was investigated by the flow cytometric methods. The effects of CBS on the biomass and bacterial activity of biofilm were investigated. Confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) were used to investigate the activity and structure of biofilms.

RESULTS

The MIC and MBC values were 18.75 µg/mL and 37.5 µg/mL. CBS could damage the cell membrane of P. gingivalis. CBS effectively inhibited biofilm formation and promoted dissociation at higher concentrations of 37.5 µg/mL and 75 µg/mL, respectively. The results also indicated an altered biofilm structure and reduced biofilm thickness and bacterial aggregation.

CONCLUSIONS

CBS affected the metabolic and physiological processes of P. gingivalis, inhibited the formation of biofilm, and disrupted the mature biofilm.

Efficacy and safety of bismuth-based quadruple therapy for Helicobacter pylori eradication in children

OBJECTIVES

To evaluate the efficacy and safety of a 10-day quadruple therapy containing colloidal bismuth sub-citrate (CBS), esomeprazole (ESO), amoxicillin (AMO), and metronidazole (MET) for Helicobacter pylori (H. pylori) eradication in children.

METHODS

Monocentric, open-label, prospective, single-arm clinical trial in children aged 6-17 years with H. pylori infection. The study was carried out on consecutive patients with upper gastrointestinal symptoms and H. pylori infection confirmed by histology and culture of gastric biopsies. The outcome was evaluated using a ¹³ C-urea breath test 8-10 weeks post-therapy. Adverse events and compliance were evaluated by daily journal and pill counting.

RESULTS

A total of 36 children fulfilling the inclusion criteria were enrolled. Eight (22.2%) of them had a prior H. pylori eradication treatment. Thirteen (36.1%) patients were infected by a strain resistant to MET and 8 (22.2%) by a strain resistant to both MET and Clarithromycin (CLA). In the intention-to-treat population (ITT), eradication was achieved in 35/36 patients (95%CI: 85%-99%). Twenty-three children reported at least one adverse event (63.8%), mostly mild (nausea, vomiting, abdominal pain, diarrhea, dark stool, metallic taste, headache, and rash). The compliance rate was high, with 30 (83.3%) patients taking >90% of the treatment.

CONCLUSION

10-day quadruple therapy containing CBS, ESO, AMO, and MET for H. pylori eradication in children is a safe and very effective solution, especially for previously treated patients and those infected with double resistant strains.

Second-Line Bismuth-Containing Quadruple Therapy for Helicobacterpylori Infection: A 12-Year Study of Annual Eradication Rates

Background: Bismuth-containing quadruple therapy (BQT) consisting of a proton-pump inhibitor (PPI), bismuth, metronidazole and tetracycline is recommended as a second-line treatment for Helicobacter pylori (H. pylori) infection when PPI-based standard triple therapy (STT) consisting of a PPI, amoxicillin and clarithromycin is unsuccessful. The purpose of this study was to analyze the long-term results of BQT as a second-line therapy to determine its effectiveness. Methods: This study included 643 subjects who failed first-line STT and received 7 or 10–14 days of BQT as a second-line therapy. We retrospectively analyzed the annual H. pylori eradication rates, demographic factors and adverse events. Results: The overall eradication rates by intention-to-treat (ITT) and per-protocol (PP) analyses were 80.7% (519/643) and 93.3% (519/556), respectively. By PP analysis, the eradication rates for 2008–2011, 2012–2015, and 2016–2019 were 93.3%, 91.0%, and 96.4%, respectively (p = 0.145). There were no significant differences between the 7-day group and the 10–14-day group in both the ITT (79.7% vs. 86.0%, p = 0.148) and the PP analyses (92.7% vs. 96.6%, p = 0.187). A multivariate analysis showed that current smoking was associated with eradication failure. Eighty-nine subjects (16.0%) suffered adverse events, mainly gastrointestinal symptoms, but only six cases were severe. Conclusions: BQT as a second-line therapy is an effective treatment for H. pylori. Treatment for 10–14 days showed a higher eradication rate compared with a 7-day regimen, but not significantly.

Evaluation of safety and pharmacokinetics of bismuth-containing quadruple therapy with either vonoprazan or lansoprazole for Helicobacter pylori eradication

Aims

Helicobacter pylori (Hp) eradication plays a key role in the treatment and prevention of peptic ulcer diseases. Increasing clarithromycin resistance in Hp necessitates more effective treatments for eradication, such as bismuth‐containing quadruple therapy. We aimed to compare the safety and pharmacokinetics (PK) of bismuth between vonoprazan‐ and lansoprazole‐containing quadruple therapy in Hp‐positive subjects.

Methods

In this randomised, double‐blind, parallel‐group study, Hp‐positive subjects were randomised to receive vonoprazan‐ or lansoprazole‐containing quadruple therapy. Each subject received vonoprazan 20 mg or lansoprazole 30 mg combined with bismuth 220 mg, clarithromycin 500 mg and amoxicillin 1000 mg twice daily for 14 days. Blood sampling and urine collection for bismuth PK were conducted predose and up to 12 hours postdose at steady‐state. The PK parameters of bismuth were derived using a noncompartmental method and compared between treatments. An exploratory breath test for Hp was conducted at screening and at the follow‐up visit on day 42. Safety was assessed by adverse event monitoring, physical examinations, vital signs, 12‐lead electrocardiograms and clinical laboratory tests.

Results

A total of 30 subjects were randomised and 26 subjects completed the study (12 in the vonoprazan group and 14 in the lansoprazole group). The systemic exposure of bismuth in the 2 treatments was comparable (~5% difference). All subjects turned negative for Hp at the follow‐up visit. No significant difference in safety profiles was noted between the 2 treatments.

Conclusion

The systemic exposure of bismuth was similar between vonoprazan‐ and lansoprazole‐containing quadruple therapy. Vonoprazan‐containing quadruple therapy was safe and well tolerated.

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.

Comparative study of allicin-containing quadruple therapy vs. bismuth-containing quadruple therapy for the treatment of Helicobacter pylori infection: a prospective randomized study

BACKGROUND

Bismuth has antimicrobial activity and can improve the efficacy of triple Helicobacter pylori (H. pylori) therapy. Allicin added to conventional therapy for H. pylori infection also improves H. pylori eradication rates. Thus, this study aims to evaluate and compare the efficacy, safety and tolerability of allicin-containing quadruple therapy and bismuth-containing quadruple therapy and to investigate the factors that affect the eradication rates.

METHODS

Two hundred twenty H. pylori-infected patients were included and randomly (1:1) assigned to 14-day quadruple therapy: ilaprazole (5 mg bid), doxycycline (100 mg bid), and furazolidone (100 mg bid) with an allicin soft capsule (40 mg of DATS tid) (IDFA) or colloidal bismuth tartrate (220 mg of elemental bismuth bid) (IDFB). Eradication was confirmed by urea breath tests. Symptom improvement, adverse events, and adherence were assessed by a questionnaire.

RESULTS

In the intention-to-treat and per-protocol analysis, the eradication rates for IDFA and IDFB groups were 87.5% (70/80) vs. 86.3% (69/80, P = 0.815) and 91.9% (68/74) vs. 91.8% (67/73, P = 0.980) as first-line therapies; 83.3% (25/30) vs. 83.3% (25/30, P = 1) and 89.3% (25/28) vs. 88.9% (24/27, P = 1) as second-line therapies. Symptom improvement rates were 96.1% and 97.0% for IDFA and IDFB (P = 1). The adverse event rates were 10.9% in IDFA and 14.5% in IDFB groups (P = 0.418). Nausea occurred frequently in IDFB than IDFA (1.8% vs. 8.2%, P = 0.030). Smoking and sharing utensils significantly affected the efficacy.

CONCLUSION

Allicin-containing quadruple therapy might be regarded as a promising alternative to bismuth-containing quadruple therapy in H. pylori eradication.

European Registry on Helicobacter pylori management (Hp-EuReg): patterns and trends in first-line empirical eradication prescription and outcomes of 5 years and 21 533 patients

OBJECTIVE

The best approach for Helicobacter pylori management remains unclear. An audit process is essential to ensure clinical practice is aligned with best standards of care.

DESIGN

International multicentre prospective non-interventional registry starting in 2013 aimed to evaluate the decisions and outcomes in H. pylori management by European gastroenterologists. Patients were registered in an e-CRF by AEG-REDCap. Variables included demographics, previous eradication attempts, prescribed treatment, adverse events and outcomes. Data monitoring was performed to ensure data quality. Time-trend and geographical analyses were performed.

RESULTS

30 394 patients from 27 European countries were evaluated and 21 533 (78%) first-line empirical H. pylori treatments were included for analysis. Pretreatment resistance rates were 23% to clarithromycin, 32% to metronidazole and 13% to both. Triple therapy with amoxicillin and clarithromycin was most commonly prescribed (39%), achieving 81.5% modified intention-to-treat eradication rate. Over 90% eradication was obtained only with 10-day bismuth quadruple or 14-day concomitant treatments. Longer treatment duration, higher acid inhibition and compliance were associated with higher eradication rates. Time-trend analysis showed a region-dependent shift in prescriptions including abandoning triple therapies, using higher acid-inhibition and longer treatments, which was associated with an overall effectiveness increase (84%-90%).

CONCLUSION

Management of H. pylori infection by European gastroenterologists is heterogeneous, suboptimal and discrepant with current recommendations. Only quadruple therapies lasting at least 10 days are able to achieve over 90% eradication rates. European recommendations are being slowly and heterogeneously incorporated into routine clinical practice, which was associated with a corresponding increase in effectiveness.

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.

Bismuth chelate as a contrast agent for X-ray computed tomography

Backgrounds

Due to the unexpected side effects of the iodinated contrast agents, novel contrast agents for X-ray computed tomography (CT) imaging are urgently needed. Nanoparticles made by heavy metal elements are often employed, such as gold and bismuth. These nanoparticles have the advantages of long in vivo circulation time and tumor targeted ability. However, due to the long residence time in vivo, these nanoparticles may bring unexpected toxicity and, the preparation methods of these nanoparticles are complicated and time—consuming.

Methods

In this investigation, a small molecular bismuth chelate using diethylenetriaminepentaacetic acid (DPTA) as the chelating agent was proposed to be an ideal CT contrast agent.

Results

The preparation method is easy and cost—effective. Moreover, the bismuth agent show better CT imaging for kidney than iohexol in the aspect of improved CT values. Up to 500 µM, the bismuth agent show negligible toxicity to L02 cells and negligible hemolysis. And, the bismuth agent did not induce detectable morphology changes to the main organs of the mice after intravenously repeated administration at a high dose of 250 mg/kg. The pharmacokinetics of the bismuth agent follows the first—order elimination kinetics and, it has a short half—life time of 0.602 h. The rapid clearance from the body promised its excellent biocompatibility.

Conclusions

This bismuth agent may serve as a potential candidate for developing novel contrast agent for CT imaging in clinical applications.

Annual eradication rate of bismuth-containing quadruple therapy as second-line treatment for Helicobacter pylori infection: A 15-year prospective study at a tertiary hospital in Korea

BACKGROUND

Bismuth-containing quadruple therapy is widely used as second-line treatment for Helicobacter pylori infection. This prospective study investigated the changes in the annual H. pylori eradication rates of quadruple therapy.

METHODS

This study included an intention-to-treat (ITT) population of 452 subjects who failed first-line eradication therapy for H. pylori between 2003 and 2018. All subjects received a 14-day course of bismuth-containing quadruple therapy consisting of esomeprazole (40 mg twice daily), metronidazole (500 mg thrice daily), bismuth subcitrate (120 mg four times daily), and tetracycline (500 mg four times daily). Per-protocol (PP) analysis of data was performed in subjects who followed up with strict treatment adherence. Eradication was confirmed based on the results of the ¹³ C-urea breath test, rapid urease test (CLOtest^® ), and histopathologic evaluation. Compliance and adverse effects were also investigated. A minimal inhibitory concentration test was performed on tissue samples obtained from 103 subjects.

RESULTS

The overall eradication rates following ITT and PP analyses were 78.8% (356/452) and 89.5% (314/351), respectively. The annual eradication success rate did not show significant changes (P = .062 [ITT], P = .857 [PP]) over the 15-year study period. Adverse events were reported in 57.3% of the ITT population. The rates of resistance to metronidazole and tetracycline were 44.7% and 18.4%, respectively.

CONCLUSIONS

Despite high antibiotic resistance rates, no significant reduction in annual eradication rates was observed during the study period.

Efficacy and safety of twice a day, bismuth-containing quadruple therapy using high-dose tetracycline and metronidazole for second-line Helicobacter pylori eradication

BACKGROUND/AIMS

Conventional second-line, bismuth-containing quadruple therapy is administered four times a day. We aimed to evaluate the efficacy and safety of twice a day administration compared to the four times a day therapy.

METHODS

Medical records of consecutive patients with positive ¹³ C-urea breath tests (UBTs) after first-line eradication were reviewed. From December 2018 to June 2019, 100 consecutive ¹³ C-UBT-positive patients received tetracycline 1 g, metronidazole 750 mg, bismuth subcitrate 300 mg, and pantoprazole 20 mg twice a day for one week. The same number of consecutive¹³ C-UBT-positive patients before December 2018 was included as controls. The control group received tetracycline 500 mg and bismuth subcitrate 300 mg four times a day, metronidazole 500 mg three times a day, and pantoprazole 20 mg twice a day for one week. Eradication was confirmed based on a ¹³ C-UBT performed in the 5th week after taking quadruple therapy.

RESULTS

Ninety-eight patients from the twice a day group and 99 patients from the four times a day group were analyzed. The eradication rate did not differ between the twice a day group (92/98, 93.9%) and the four times a day group (92/99, 92.9%). Adverse drug effects were found in 36 patients from the twice a day group and 50 patients from the four times a day group (P = .051). Abdominal pain, discomfort, and distention were more common with four times a day intake (13.1%) than with twice a day intake (4.1%; P = .024).

CONCLUSIONS

We determined for the first time that twice a day intake of bismuth-containing quadruple therapy using 2 g/d of tetracycline, 1.5 g/d of metronidazole, and 600 mg/d of bismuth subcitrate for one week is effective and safe as the conventional four times a day therapy. Twice a day intake decreased abdominal pain, discomfort, and distention.

Comparison of four different regimens against Helicobacter pylori as a first-line treatment: A prospective, cross-sectional, comparative, open trial in Chinese children

BACKGROUNDS

Due to the decreasing eradication rate of Helicobacter pylori, some novel alternatives have been developed, such as bismuth-containing quadruple therapy and non-bismuth-containing quadruple therapy (sequential and concomitant treatment). Little is known about whether a success rate above 90% can be achieved with these regimens in Chinese children.

METHODS

In this prospective, open, comparative cross-sectional study, we recruited treatment-naïve children (aged between 6 and 18 years) with H pylori infection. The patients were assigned either standard triple therapy, sequential therapy, bismuth-based quadruple therapy, or concomitant therapy at the discretion of the prescribing physician. H pylori infection was evaluated at least 4 weeks after the completion of the treatment. A negative urea breath test (UBT) indicated successful eradication. The primary endpoint was the eradication frequency of H pylori in the full analysis set (FAS), which included all children who received at least one dose of the treatment and with available follow-up data.

RESULTS

Between September 2017 and December 2018, 228 patients were finally included in the FAS analyses. The eradication rates were 74.1% for standard triple therapy (43/58, [95% CI: 62.8%-85.5%]), 69.5% for sequential therapy (41/59, [95% CI: 57.8%-81.2%]), 89.8% for bismuth-based quadruple therapy (53/59, [95% CI: 82.1%-97.5%]), and 84.6% for concomitant therapy (44/52, [95% CI: 74.8%-94.4%]). Bismuth-based therapy was superior to triple therapy, while sequential therapy and concomitant therapy were not superior to triple therapy. The frequency of adverse events was 12.1% (7/58) in standard triple therapy, 6.8% (4/59) in sequential therapy, 15.3% (9/59) in bismuth-based therapy, and 15.4% (8/52) in concomitant therapy. The rate of adverse events was similar among the four groups.

CONCLUSION

Bismuth quadruple therapy can achieve an eradication rate of 89.8% as first-line treatment and is safe and well tolerated. Bismuth could be a promising alternative as a first-line regimen in Chinese children.

Oral immunization of mice with a multivalent therapeutic subunit vaccine protects against Helicobacter pylori infection

Helicobacter pylori is a human class I carcinogen and no effective prophylactic or therapeutic H. pylori vaccine has yet been marketed. H. pylori can escape the host immune response, but the precise immune protection mechanisms in humans remain unknown. In this study, we developed a multivalent, subunit H. pylori vaccine candidate by formulating three commonly used H. pylori antigens, neutrophil-activating protein (NAP), urease subunit A (UreA) and subunit B (UreB) with the mucosal adjuvant, a double-mutant heat-labile toxin (dmLT) from Escherichia coli, and evaluated its immunogenicity and therapeutic efficacy in a mouse model of H. pylori infection. We found that oral immunization of H. pylori-infected mice significantly reduced gastric bacterial colonization at both 2 and 8 weeks after immunization. The reduction in bacterial burdens was accompanied with significantly increased serum antigen-specific IgG responses and mucosal IgA responses. Moreover, oral immunization also induced Th1/Th17 immune responses, which may play a synergistic role with the specific antibodies in the elimination of H. pylori. Thus, our vaccine candidate appears able to overcome the immune evasion mechanism of H. pylori, restore the suppression of Th2 immune responses with the induction of a strong humoral immune response. These results lay the foundation for the development of an optimized oral therapeutic H. pylori vaccine with increased immunogenicity of UreA and UreB, as well as providing long-term immunity.

What Would the Screen-and-Treat Strategy for Helicobacter pylori Mean in Terms of Antibiotic Consumption?

Several guidelines recommend the screen-and-treat strategy, i.e. active search for the presence of Helicobacter pylori infection and its eradication to prevent the possibility of gastric cancer. It is thought that a relatively short duration antibiotic regimen given once in a lifetime would not significantly increase overall antibiotic consumption. However, this would mean offering antibiotic treatment to the majority of the population in countries with the biggest burden of gastric cancer who would, therefore, have the greatest benefit from such a strategy. So far, no country has implemented an eradication strategy. With an example based on the current situation in Latvia, we have estimated the increase in antibiotic consumption if the screen-and-treat strategy was applied. Depending on the scenario that might be chosen, clarithromycin consumption would increase up to sixfold, and amoxicillin consumption would double if the recommendations of the current guideline in the local circumstances was applied. It appears that an increase in commonly used antibiotic consumption cannot be justified from the viewpoint of antibiotic stewardship policies. Solutions to this problem could be the use of antibiotics that are not required for treating life-threatening diseases or more narrow selection of the target group, e.g. young people before family planning to avoid transmission to offspring. Additional costs related to the increase in resistome should be considered for future cost-effectiveness modelling of the screen-and-treat strategy.

Pylera® plus ranitidine vs Pylera® plus esomeprazole in first-line treatment of Helicobacter pylori infection: Two pilot studies

BACKGROUND

Several studies have shown that Pylera^® (three-in-one capsules containing 140 mg bismuth potassium subcitrate, 125 metronidazole, and tetracycline 125 mg) in association with omeprazole or esomeprazole is a good option in the treatment of Helicobacter pylori infection. In particular, the adjunction of a PPI to Pylera^® may be useful to overcome metronidazole resistance. However, omeprazole and its derivatives can promote greater bismuth absorption and enhance its toxicity. The H2 receptor antagonist (H2RA) ranitidine seems to induce less bismuth absorption and as a consequence less systemic toxicity.

AIM

To evaluate whether Pylera^® in combination with esomeprazole or with ranitidine is equally effective in the treatment of H. pylori infection.

MATERIAL AND METHODS

Two separate groups of patients were treated simultaneously. One group was treated with Pylera^® three capsules qid plus esomeprazole 40 mg bid for 10 days (group A), and the other group was treated with Pylera^® three capsules qid plus ranitidine 300 mg bid for 10 days (group B). H. pylori eradication was defined as a negative result in ¹³ C urea breath test performed at least 8 weeks after the end of treatment with a delta-over-baseline value less than 5.

RESULTS

Thirty-two patients were recruited for group A and thirty-three patients in group B. Eradication rates were 93.7% (30/32) and 90.9% (30/33), respectively, at intention-to-treat analysis, and 96.6% (29/30) and 93.3% (28/30), respectively, at per-protocol analysis. Adverse events occurred in 26 patients and led to the suspension of treatment in one patient in group A and in one patient in group B.

CONCLUSION

The results showed that Pylera® plus a PPI or ranitidine were equally effective in the population studied. The high cure rates of bismuth triple therapy (without an antisecretory drug) and the lack of susceptibility testing make it impossible to exclude the possibility that the results would have been similar if neither the PPI nor the ranitidine were given.

Review of current diagnostic methods and advances in Helicobacter pylori diagnostics in the era of next generation sequencing

Helicobacter pylori (H. pylori) infection is highly prevalent in the human population and may lead to severe gastrointestinal pathology including gastric and duodenal ulcers, mucosa associated tissue lymphoma and gastric adenocarcinoma. In recent years, an alarming increase in antimicrobial resistance and subsequently failing empiric H. pylori eradication therapies have been noted worldwide, also in many European countries. Therefore, rapid and accurate determination of H. pylori’s antibiotic susceptibility prior to the administration of eradication regimens becomes ever more important. Traditionally, detection of H. pylori and its antimicrobial resistance is done by culture and phenotypic drug susceptibility testing that are cumbersome with a long turn-around-time. Recent advances in diagnostics provide new tools, like real-time polymerase chain reaction (PCR) and line probe assays, to diagnose H. pylori infection and antimicrobial resistance to certain antibiotics, directly from clinical specimens. Moreover, high-throughput whole genome sequencing technologies allow the rapid analysis of the pathogen’s genome, thereby allowing identification of resistance mutations and associated antibiotic resistance. In the first part of this review, we will give an overview on currently available diagnostic methods for detection of H. pylori and its drug resistance and their implementation in H. pylori management. The second part of the review focusses on the use of next generation sequencing technology in H. pylori research. To this end, we conducted a literature search for original research articles in English using the terms “Helicobacter”, “transcriptomic”, “transcriptome”, “next generation sequencing” and “whole genome sequencing”. This review is aimed to bridge the gap between current diagnostic practice (histology, rapid urease test, H. pylori culture, PCR and line probe assays) and new sequencing technologies and their potential implementation in diagnostic laboratory settings in order to complement the currently recommended H. pylori management guidelines and subsequently improve public health.

Bismuth supplements as the first-line regimen for Helicobacter pylori eradication therapy: Systemic review and meta-analysis

BACKGROUND AND AIMS

An increase in the use of antibiotics leads to increased antibiotic resistance of Helicobacter pylori (H pylori). Consequently, it has been considered that the first-line standard regimen should be changed. The main purpose of this study was to evaluate the efficacy of nonantibiotic (bismuth) supplements as a first-line regimen for H pylori eradication.

METHODS

We searched PubMed, EMBASE, CINAHL, and the Cochrane Library databases for randomized controlled trials (RCTs) reported in English and undertaken up until August 2018. A meta-analysis of all randomized controlled trials comparing bismuth supplements with non-bismuth-containing regimens in H pylori eradication was performed. RCTs of classic bismuth-containing quadruple therapy as a first-line regimen were excluded.

RESULTS

We identified twenty-five randomized trials (3990 patients), and the total H pylori eradication rate, according to per protocol analyzed, was 85.8%. The odds ratio was 1.83 (95% confidence interval (CI). 1.57-2.13). Among these RCTs, there were 7 RCTs for bismuth add-on therapy, and the odds ratio was 2.81 (95% CI. 2.03-3.89). When the studies were performed in a high clarithromycin resistance area (≥15%) or included patients with clarithromycin resistance, bismuth-containing regimens were superior to non-bismuth regimens. Moreover, the incidence of total side effects was insignificant.

CONCLUSIONS

Bismuth supplements as a first-line regimen could be effective, with bismuth add-on regimens being the most effective. Particularly, bismuth supplements showed the potential efficacy for clarithromycin-resistant strains and would be the most viable alternative in clinical practice.

Treatment of Helicobacter pylori infection in atrophic gastritis

Helicobacter pylori (Hp) is a major human pathogen causing chronic, progressive gastric mucosal damage and is linked to gastric atrophy and cancer. Hp-positive individuals constitute the major reservoir for transmission of infection. There is no ideal treatment for Hp. Hp infection is not cured by a single antibiotic, and sometimes, a combined treatment with three or more antibiotics is ineffective. Atrophic gastritis (AG) is a chronic disease whose main features are atrophy and/or intestinal metaplasia of the gastric glands, which arise from long-standing Hp infection. AG is reportedly linked to an increased risk for gastric cancer, particularly when extensive intestinal metaplasia is present. Active or past Hp infection may be detected by conventional methods in about two-thirds of AG patients. By immunoblotting of sera against Hp whole-cell protein lysates, a previous exposure to Hp infection is detected in all AG patients. According to guidelines, AG patients with Hp positivity should receive eradication treatment. The goals of treatment are as follows: (1) Cure of infection, resolution of inflammation and normalization of gastric functions; (2) possible reversal of atrophic and metaplastic changes of the gastric mucosa; and (3) prevention of gastric cancer. An ideal antibiotic regimen for Hp should achieve eradication rates of approximately 90%, and complex multidrug regimens are required to reach this goal. Amongst the factors associated with treatment failure are high bacterial load, high gastric acidity, Hp strain, smoking, low compliance, overweight, and increasing antibiotic resistance. AG, when involving the corporal mucosa, is linked to reduced gastric acid secretion. At a non-acidic intra-gastric pH, the efficacy of the common treatment regimens combining proton pump inhibitors with one or more antibiotics may not be the same as that observed in patients with Hp gastritis in an acid-producing stomach. Although the efficacy of these therapeutic regimens has been thoroughly tested in subjects with Hp infection, there is a paucity of evidence in the subgroup of patients with AG. Bismuth-based therapy may be an attractive treatment in the specific setting of AG, and specific studies on the efficacy of bismuth-based therapies are needed in patients with AG.

Efficacy and Tolerability of Two Quadruple Regimens: Bismuth, Omeprazole, Metronidazole with Amoxicillin or Tetracycline as First-Line Treatment for Eradication of Helicobacter Pylori in Patients with Duodenal Ulcer: A Randomized Clinical Trial

AIM

To evaluate the efficacy and tolerability of tetracycline vs. high-dose amoxicillin in bismuth-based quadruple therapy for Helicobacter pylori(H. pylori) eradication.

METHODS

This randomized, open-label clinical trial included 228 patients with H.pylori infection and duodenal ulcer without a history of H.pylori treatment. Patients were randomly divided into two groups. The amoxicillin group received metronidazole 500mg, bismuth subcitrate 240mg, and amoxicillin 1000mg, all three times a day, plus omeprazole 20 mg twice a day, for 14 days. The tetracycline group received metronidazole 500mg three times a day; bismuth subcitrate240mg and tetracycline HCl 500mg, both four times a day; and omeprazole 20 mg twice a day, for 14 days. Evaluation for compliance and drug-relatedadverse effects were evaluated at the end of two weeks. Eight weeks after the end of treatment, the rate of H.pylori eradication was assessed by the C13urease breath test.

RESULTS

There were no significant demographic differences between the two groups. Eradication rate was higher with the amoxicillin-containing regimen than the tetracycline-containing regimen: 105/110 (95.51%; 95% confidence interval, 91.5%-99.3%) vs. 88/105 (83.8%; 95%CI, 76.7%-90.8%) by per-protocol analysis (p = 0.005) and 92.9% (95%CI, 88.1%-97.6%) vs. 76.5% (95%CI, 68.7%-84.2%) by intention-to-treat analysis (ITT, p = 0.001). Adverse effects were significant higher in the tetracycline groupthan in the amoxicillin group (65.2% vs. 43.4%; p = 0.001).

CONCLUSION

Bismuth-based quadruple therapy including high-dose amoxicillin and metronidazole achieved an acceptable rate of H.pylori infection eradication with good tolerance in patients with duodenal ulcer. This regimen can overcome treatment resistance in areas with high prevalence of metronidazole and clarithromycin resistance.

TRIAL REGISTRATION

The Thai Clinical Trial Registry (TCTR) 20170623004.

Fifth Chinese National Consensus Report on the management of Helicobacter pylori infection

BACKGROUND

Since the 'Fourth Chinese National Consensus Report on the management of H. pylori infection' was published in 2012, three important consensuses (Kyoto global consensus report on H. pylori gastritis, The Toronto Consensus for the Treatment of H. pylori Infection in Adults and Management of H. pylori infection-the Maastricht V/Florence Consensus Report) have been published regarding the management of H. pylori infection.

MATERIALS AND METHODS

A Delphi method was adopted to develop the consensus of relevant 'statements'. First, the established 'statements' were sent to experts via email. Second, after undergoing two rounds of consultation, the initial statements were discussed face to face and revised in the conference item by item on 16 December 2016. Finally, 21 core members of conferees participated in the final vote of statements. Voting for each statement was performed using an electronic system with levels of agreements shown on the screen in real time.

RESULTS

Consensus contents contained a total of 48 "statements" and related 6 parts, including indications for H. pylori eradication, diagnosis, treatment, H. pylori and gastric cancer, H. pylori infection in special populations, H. pylori and gastrointestinal microbiota.

CONCLUSIONS

Recommendations are provided on the basis of the best available evidence.

Efficacy of three-in-one capsule bismuth quadruple therapy for Helicobacter pylori eradication in clinical practice in a multinational patient population

BACKGROUND

Bismuth quadruple therapy (BQT) has been proven superior to standard triple therapy for Helicobacter pylori eradication in randomized clinical trials; however, little is known about the efficacy of BQT in daily routine practice.

METHODS

In a single-center cohort study, we analyzed consecutive H. pylori-positive patients in whom three-in-one capsule BQT (Pylera^® + omeprazole) has been prescribed. All patients were instructed in a standardized fashion, and a prospective follow-up was planned. PCR on gastric biospies for clarithromycin and levofloxacin resistance was performed before treatment in a subgroup of patients. Treatment outcome was assessed by 13C urea breath test or by histology not earlier than 4 weeks after end of treatment.

RESULTS

Three-in-one capsule BQT has been prescribed in 322 patients. Approximately 70.2% of patients had a migrational background. PCR results were available in 163 patients and identified resistance to clarithromycin and levofloxacin in 29 (17.8%) and 20 (12.3%) of cases, respectively. BQT was prescribed as first-line, second-line, and salvage treatments in 74%, 17%, and 9% of cases, respectively. Five patients discontinued treatment due to side effects (1.8%). By modified intention-to-treat and per-protocol analyzes, the overall H. pylori eradication rates were 95.0% (95% CI 94.92%-95.08%) and 96.7% (95% CI 94.6%-98.8%), respectively. The low number of treatment failures (n = 9) did not allow to identify risk factors for failure.

CONCLUSION

Three-in-one capsule bismuth quadruple therapy is effective and safe for treatment of H. pylori infection in routine practice, irrespective of the patient's migrational background or the number of previous treatment failures.

Optimization strategies aimed to increase the efficacy of H. pylori eradication therapies

BACKGROUND

As with any other infectious disease, we should aim for treatments offering ≥90% Helicobacter pylori eradication rates in clinical practice.

AIM

To summarize optimization strategies aimed to increase the efficacy of H. pylori eradication therapies.

METHODS

A systematic bibliographic search (in PubMed up to August 2016) was designed to identify studies investigating optimization strategies aimed to increase the efficacy of H. pylori eradication therapies.

RESULTS

The most direct way to optimize a treatment is using higher doses of drugs unless it has been shown that lower doses are equally effective. Similarly, prescriptions should use 14-day duration unless a shorter scheme has been shown locally to be equally effective. Double-dose proton-pump inhibitor therapy is recommended for triple therapy and may probably increase the efficacy of nonbismuth concomitant regimen as well. The efficacy of triple therapies in the presence of resistance can be significantly improved by the addition of bismuth salts, which offer an additive effect in combination with antibiotics. Overall, probiotics seem to reduce antibiotic side effects, but the increase in eradication rates is not so evident; therefore, they cannot be generally recommended for clinical practice yet.

CONCLUSIONS

Using potent acid inhibition and/or higher antibiotic doses-especially by increasing the number of daily intakes-and lengthening treatments up to 14 days improves efficacy in most regimens and should be generally recommended. Triple therapies can be efficiently improved by the addition of bismuth salts, turning them into quadruple therapies. Finally, some treatments will require a combination of optimization strategies to significantly improve results.

Novel and Effective Therapeutic Regimens for Helicobacter pylori in an Era of Increasing Antibiotic Resistance

Helicobacter pylori (H. pylori) is a common gastrointestinal bacterial strain closely associated with the incidence of chronic gastritis, peptic ulcers, gastric mucosa-associated lymphoid tissue lymphoma, and gastric cancer. A current research and clinical challenge is the increased rate of antibiotic resistance in H. pylori, which has led to a decreased H. pylori eradication rate. In this article, we review recent H. pylori infection and reinfection rates and H. pylori resistance to antibiotics, and we discuss the pertinent treatments. A PubMed literature search was performed using the following keywords: Helicobacter pylori, infection, reinfection, antibiotic resistance, bismuth, proton pump inhibitors, vonoprazan, susceptibility, quintuple therapy, dual therapy, and probiotic. The prevalence of H. pylori has remained high in some areas despite the decreasing trend of H. pylori prevalence observed over time. Additionally, the H. pylori reinfection rate has varied in different countries due to socioeconomic and hygienic conditions. Helicobacter pylori monoresistance to clarithromycin, metronidazole or levofloxacin was common in most countries. However, the prevalence of amoxicillin and tetracycline resistance has remained low. Because H. pylori infection and reinfection present serious challenges and because H. pylori resistance to clarithromycin, metronidazole or levofloxacin remains high in most countries, the selection of an efficient regimen to eradicate H. pylori is critical. Currently, bismuth-containing quadruple therapies still achieve high eradication rates. Moreover, susceptibility-based therapies are alternatives because they may avoid the use of unnecessary antibiotics. Novel regimens, e.g., vonoprazan-containing triple therapies, quintuple therapies, high-dose dual therapies, and standard triple therapies with probiotics, require further studies concerning their efficiency and safety for treating H. pylori.

Management of Helicobacter pylori infection-the Maastricht V/Florence Consensus Report

Important progress has been made in the management of Helicobacter pylori infection and in this fifth edition of the Maastricht Consensus Report, key aspects related to the clinical role of H. pylori were re-evaluated in 2015. In the Maastricht V/Florence Consensus Conference, 43 experts from 24 countries examined new data related to H. pylori in five subdivided workshops: (1) Indications/Associations, (2) Diagnosis, (3) Treatment, (4) Prevention/Public Health, (5) H. pylori and the Gastric Microbiota. The results of the individual workshops were presented to a final consensus voting that included all participants. Recommendations are provided on the basis of the best available evidence and relevance to the management of H. pylori infection in the various clinical scenarios.

Rifabutin Containing Triple Therapy and Rifabutin with Bismuth Containing Quadruple Therapy for Third-Line Treatment of Helicobacter pylori Infection: Two Pilot Studies

AIM

To evaluate the therapeutic gain of the addition of bismuth to a rifabutin containing triple therapy with amoxicillin and pantoprazole at standard dosages for the treatment of third-line Helicobacter pylori infection after a preliminary susceptibility test.

METHODS

Two separate groups of patients in two pilot studies which were carried out simultaneously. One group was treated with rifabutin 150 mg b.i.d., pantoprazole 20 mg b.i.d., and amoxicillin 1 g b.i.d. for 10 days and the other group with rifabutin 150 mg b.i.d., pantoprazole 20 mg b.i.d., amoxicillin 1 g b.i.d., and bismuth subcitrate 240 mg b.i.d. for 10 days. All patients underwent to culture and susceptibility testing prior to their inclusion in the study. A successful outcome was confirmed with an Urea Breath test performed 8 weeks after the end of treatment. A blood cell count was performed for all patients at the start and after 5 days of treatment since rifabutin has been shown to inhibit the growth of leucocytes.

RESULTS

Twenty-nine patients were recruited in the pantoprazole, amoxicillin, rifabutin group and 30 in the pantoprazole, amoxicillin, rifabutin, and bismuth subcitrate group. All patients had a positive H. pylori culture and the susceptibility test used showed H. pylori sensitivity to rifabutin and amoxicillin. H. pylori eradication during follow-up was 18/27 (66.7%, 95% CI: 47.7-85.7%) in the pantoprazole, amoxicillin, rifabutin group and 28/29 (96.6%, 95% CI: 89.5-100.0%) in the pantoprazole, amoxicillin, rifabutin, and bismuth subcitrate group. Both treatments were well-tolerated with no reported side effects. Blood cell count remained normal in all patients.

CONCLUSION

The addition of bismuth subcitrate to a triple therapy that includes proton pump inhibitors, amoxicillin, and rifabutin in patients who are treated for the third time for H. pylori infection resulted in a 30% therapeutic gain.

Pharmacological regimens for eradication of Helicobacter pylori: an overview of systematic reviews and network meta-analysis

BACKGROUND

Approximately half of the world's population is infected with Helicobacter pylori (H.pylori), a bacterium shown to be linked with a series of gastrointestinal diseases. A growing number of systematic reviews (SRs) have been published comparing the effectiveness of different treatments for H.pylori infection but have not reached a consistent conclusion. The objective of this study is to provide an overview of SRs of pharmacological therapies for the eradication of H.pylori.

METHODS

Major electronic databases were searched to identify relevant SRs published between 2002 and February 2016. Studies were considered eligible if they included RCTs comparing different pharmacological regimens for treating patients diagnosed as H.pylori infected and pooled the eradication rates in a meta-analysis. A modified version of the 'A Measurement Tool to Assess Systematic Reviews' (AMSTAR) was used to assess the methodological quality. A Bayesian random effects network meta-analysis (NMA) was conducted to compare the different proton pump inhibitors (PPI) within triple therapy.

RESULTS

30 SRs with pairwise meta-analysis were included. In triple therapy, the NMA ranked the esomeprazole to be the most effective PPI, followed by rabeprazole, while no difference was observed among the three old generations of PPI for the eradication of H.pylori. When comparing triple and bismuth-based therapy, the relative effectiveness appeared to be dependent on the choice of antibiotics within the triple therapy; moxifloxacin or levofloxacin-based triple therapy were both associated with greater effectiveness than bismuth-based therapy as a second-line treatment, while bismuth-based therapy achieved similar or greater eradication rate compared to clarithromycin-based therapy. Inconsistent findings were reported regarding the use of levofloxacin/moxifloxacin in the first-line treatment; this could be due to the varied resistant rate to different antibiotics across regions and populations. Critical appraisal showed a low-moderate level of overall methodological quality of included studies.

CONCLUSIONS

Our analysis suggests that the new generation of PPIs and use of moxifloxacin or levofloxacin within triple therapy as second-line treatment were associated with greater effectiveness. Given the varied antibiotic resistant rate across regions, the appropriateness of pooling results together in meta-analysis should be carefully considered and the recommendation of the choice of antibiotics should be localized.

Failed Eradication for Helicobacter pylori. What Should Be Done?

Failed eradication of Helicobacter pylori occurs when the antibiotic concentration at the site where H. pylori is located is lower than the minimal inhibitory concentration of the antibiotic for this bacterium. The main reason for this is the acquisition of resistance; and in the context of the most common treatment, the main reason is the acquisition of resistance to clarithromycin. Several options can then be followed. The most rational option is to use a tailored therapy, that is, to look for clarithromycin resistance either by culture plus antibiogram or by a molecular method. The standard triple therapy is used only in the case of clarithromycin susceptibility. In case of resistance or if an empiric treatment must be given, a good option is to use a bismuth-based quadruple therapy. If unavailable, clarithromycin-based quadruple therapies can be used either as sequential or 'concomitant' or hybrid. The limit, especially for concomitant therapy, is the use of clarithromycin, which will be inactive in about 2/3 of the cases, adding to cost and adverse events. Recently, the dual therapy proton pump inhibitor-amoxicillin has been revisited especially in the Far East, and increasing the dose and the frequency of administration gives excellent results.

Levofloxacin, bismuth, amoxicillin and esomeprazole as second-line Helicobacter pylori therapy after failure of non-bismuth quadruple therapy

BACKGROUND

The best rescue therapy for Helicobacter pylori (H. pylori) infection following failure of non-bismuth quadruple therapy (NBQT) remains unanswered.

AIMS

To determine the efficacy, safety and compliance of levofloxacin, bismuth, amoxicillin and esomeprazole (LBAE) regimen following failure of NBQT.

METHODS

132 patients with H. pylori infection refractory to first-line NBQT received LBAE regimen (levofloxacin 500mg once/day, bismuth potassium citrate 220mg twice/day, amoxicillin 1000mg twice/day and esomeprazole 20mg twice/day for 14 days). Gastric mucosal biopsy was obtained for H. pylori culture, antimicrobial sensitivity test and cytochrome P450 isoenzyme 2C19 polymorphism analysis.

RESULTS

LBAE therapy achieved eradication rates of 73.5% [95% confidence intervals (CI) 65.9-81.1%] in intention-to-treat and 78.5% (71.1-85.9%) in per-protocol analyses in patients with high antibiotic resistance (amoxicillin 8.3%, clarithromycin 55.6%, metronidazole 73.6% and levofloxacin 36.1%). Adverse effects were found in 19.2% and compliance in 96.1% of the treated patients. Multivariate analyses identified levofloxacin resistance [odds ratio (OR) 7.183, 95% CI 1.616-31.914, P=0.010] and history of quinolone intake (4.844, 1.174-19.983, P=0.029) as independent predictors of treatment failure. The eradication rate of patients with dual amoxicillin and levofloxacin resistance was significantly decreased (33.3%, P=0.006).

CONCLUSIONS

In populations with high levofloxacin resistance, 14-day second-line LBAE regimen resulted in an unsatisfactory efficacy in patients resistant to NBQT despite good safety and compliance.