Pantoprazole based therapies in Helicobacter pylori eradication: a systematic review and meta-analysis

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.

Evidence-based assessment of proton-pump inhibitors in Helicobacter pylori eradication: A systematic review

Peptic ulcer disease continues to be issue especially due to its high prevalence in the developing world. Helicobacter pylori (H. pylori) infection associated duodenal ulcers should undergo eradication therapy. There are many regimens offered for H. pylori eradication which include triple, quadruple, or sequential therapy regimens. The central aim of this systematic review is to evaluate the evidence for H. pylori therapy from a meta-analytical outlook. The consequence of the dose, type of proton-pump inhibitor, and the length of the treatment will be debated. The most important risk factor for eradication failure is resistance to clarithromycin and metronidazole.

[Ideal treatment for Helicobacter pylori: a systematic review]

BACKGROUND

The success rates of therapies for treating Helicobacter pylori vary greatly worldwide and the ideal treatment has yet to be clearly established.

AIMS

A systematic review was carried out to evaluate the effectiveness of current first and second-line therapies in treating H.pylori infection.

METHODS

Two researchers independently carried out Internet search engine reviews (PUBMED, EMBASE, MEDLINE) of clinical trials on adults published between 1990 and 2012 in both English and Spanish.

RESULTS

Forty-three (n=8,123) clinical trials were evaluated that included first and second-line triple, quadruple, and sequential therapies. The eradication rates of the standard triple therapy are unacceptable (≤80%) in countries where H.pylori is highly resistant to clarithromycin and metronidazole. Administration of the standard triple therapy for more than 7 days does not improve its effectiveness. No statistically significant differences were observed between the eradication rates of the quadruple therapy with bismuth and the standard triple therapy. Even though the sequential and concomitant therapies are equally successful regimens, the triple therapy with levofloxacin offers the best results as first and second-line treatment, but quinolone resistance can diminish its effectiveness. The triple therapy with levofloxacin and the sequential and concomitant treatments were superior to the standard triple regimen as first-line therapy.

CONCLUSIONS

Currently there is no ideal first or second-line treatment for achieving 100% eradication. The therapeutic order should be carried out according to the initial treatment and local antimicrobial resistance studies.

Randomised clinical trial: simvastatin as adjuvant therapy improves significantly the Helicobacter pylori eradication rate--a placebo-controlled study

BACKGROUND

The eradication rate of Helicobacter pylori with standard treatments are decreasing worldwide.

AIM

To determine whether adding simvastatin as adjuvant to triple regimen in patients with H. pylori infection will improve the eradication rate.

METHODS

We conducted a double-blind, placebo-controlled, randomised clinical trial comparing a 7-day, triple eradication regimen consisting of two antibiotics (clarithromycin 500 mg and amoxicillin 1 g, all twice per day) plus a proton pump inhibitor (omeprazole 20 mg twice daily) supplemented with simvastatin 20 mg (CAO + S) or a comparable placebo (CAO + P). Both the simvastatin and the placebo were taken orally twice daily for 1 week in 113 patients with H. pylori infection. The presence of H. pylori was determined by positive rapid urease test and histology. Eradication was confirmed by ¹³C-urea breath test at least 1 month after treatment. Adverse effects were assessed by questionnaire.

RESULTS

A total of 113 patients underwent randomisation. Intention-to-treat analysis (ITT; n = 113) eradication rates were: CAO + S (86%; 95% CI: 78-92%), CAO + P (69%; 95% CI: 64-74%). Per protocol analysis (PP; n = 108) eradication rates were: CAO + S (91%; 95% CI: 84-94%), CAO + P (72%; 95% CI: 65-78%). Eradication rates were higher with CAO + S than CAO + P in PP and ITT (P = 0.03, P = 0.04 respectively). No differences were demonstrated between the two groups concerning compliance or adverse effects.

CONCLUSION

In this randomised clinical trial simvastatin as adjuvant to standard therapy improves significantly the H. pylori eradication rate.

Ilaprazole, a new proton pump inhibitor, is primarily metabolized to ilaprazole sulfone by CYP3A4 and 3A5

Ilaprazole is a new proton pump inhibitor, designed for treatment of gastric ulcers, and developed by Il-Yang Pharmaceutical Co (Seoul, Korea). It is extensively metabolised to the major metabolite ilaprazole sulfone. In the present study, several in vitro approaches were used to identify the cytochrome P450 (CYP) enzymes responsible for ilaprazole sulfone formation. Concentrations of ilaprazole sulfone were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Incubation of ilaprazole with cDNA-expressed recombinant CYPs indicated that CYP3A was the major enzyme that catalyses ilaprozole to ilaprazole sulfone. This reaction was inhibited significantly by ketoconazole, a CYP3A inhibitor, and azamulin, a mechanism-based inhibitor of CYP3A, while no substantial effect was observed using selective inhibitors for eight other P450s (CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, and CYP2E1). In addition, the formation of ilaprazole sulfone correlated well with CYP3A-catalysed testosterone 6β-hydroxylation and midazolam 1'-hydroxylation in 20 different human liver microsome panels. The intrinsic clearance of the formation of ilaprazole sulfone by CYP3A4 was 16-fold higher than that by CYP3A5. Collectively, these results indicate that the formation of the major metabolite of ilaprazole, ilaprazole sulfone, is predominantly catalysed by CYP3A4/5.

[Evidence and uncertainties on the clinical use of proton pump inhibitors]

Proton pump inhibitors (PPI) are the most potent and effective drugs for the control of gastric acid secretion and constitute one of the most widely prescribed pharmacological groups worldwide. The safety and efficacy of PPI have been demonstrated in clinical practice and these drugs are currently the treatment of choice in peptic ulcer diseases, Helicobacter pylori infection, gastroesophageal reflux disease, nonsteroidal antiinflammatory drug gastropathy and functional dyspepsia. However, despite the excellent pharmacological profile of current PPI, their rapidity of action may be insufficient in some diseases, 24-hour acid inhibition is not always achieved and - to a greater or lesser extent depending on the distinct molecules of the PPI - there is interindividual variability in gastric antisecretory efficacy, depending on genetic polymorphism of CYP2C19, which could affect individual metabolism of the distinct PPI. New generations of these drugs will probably eliminate these deficiencies.

First-line eradication of Helicobacter pylori: Are the standard triple therapies obsolete? A different perspective

Studies concerning the eradication of Helicobacter pylori have resulted in a proliferation of meta-analyses. To date, there are 303 meta-analyses cited in PubMed, 113 dealing with the therapy of the infection. A chronological analysis of the results of meta-analyses performed between 1998 and 2010 shows that first-line standard triple therapies achieved eradication rates on an intention-to-treat basis of around 80%; prolonging treatment to 14, but not 10 d should improve the results. The proton pump inhibitors have a similar efficiency, and giving a double dose is more efficient than the standard doses of these drugs. Triple and quadruple therapies proved to be equivalent. Based on meta-analytical data, the decrease in efficiency over time cannot be substantiated: eradication rates < 80% followed from the introduction of triple therapies. As alternatives, ranitidine bismuth citrate-, levofloxacin- or furazolidone-based therapies were shown to obtain the same eradication rates as standard triple regimens. Sequential therapies and quadruple non-bismuth-based therapies were superior to standard triple therapies but their use is limited to certain countries. In the author’s opinion, and from a meta-analytical viewpoint, standard triple therapies cannot yet be considered obsolete. Furthermore, non-inferiority trials are proposed for the future, including assessment of local contemporary antimicrobial resistance profiles and the CagA and CYP2C19 status of the enrolled patients.

Proton pump inhibitors: an update of their clinical use and pharmacokinetics

BACKGROUND

Proton pump inhibitors (PPIs) represent drugs of first choice for treating peptic ulcer, Helicobacter pylori infection, gastrooesophageal reflux disease, nonsteroidal anti-inflammatory drug (NSAID)-induced gastrointestinal lesions (complications), and Zollinger-Ellison syndrome.

RESULTS

The available agents (omeprazole/esomeprazole, lansoprazole, pantoprazole, and rabeprazole) differ somewhat in their pharmacokinetic properties (e.g., time-/dose-dependent bioavailability, metabolic pattern, interaction potential, genetic variability). For all PPIs, there is a clear relationship between drug exposure (area under the plasma concentration/time curve) and the pharmacodynamic response (inhibition of acid secretion). Furthermore, clinical outcome (e.g., healing and eradication rates) depends on maintaining intragastric pH values above certain threshold levels. Thus, any changes in drug disposition will subsequently be translated directly into clinical efficiency so that extensive metabolizers of CYP2C19 will demonstrate a higher rate of therapeutic nonresponse.

CONCLUSIONS

This update of pharmacokinetic, pharmacodynamic, and clinical data will provide the necessary guide by which to select between the various PPIs that differ-based on pharmacodynamic assessments-in their relative potencies (e.g., higher doses are needed for pantoprazole and lansoprazole compared with rabeprazole). Despite their well-documented clinical efficacy and safety, there is still a certain number of patients who are refractory to treatment with PPIs (nonresponder), which will leave sufficient space for future drug development and clinical research.

Quadruple rescue therapy for Helicobacter pylori infection after two treatment failures

BACKGROUND

A standard third-line therapy for Helicobacter pylori infection is lacking, and antimicrobial sensitivity data for patients who failed eradication therapy are often unavailable in clinical practice. We therefore designed the prospective study to assess the efficacy of levofloxacin, amoxicillin, bismuth and rabeprazole quadruple therapy as a third-line treatment for H. pylori infection.

PATIENTS AND METHODS

From September 2005 to August 2007, 37 consecutive H. pylori-infected patients who had failed standard first-line and second-line treatments underwent a 10-day quadruple therapy comprising rabeprazole (20 mg b.i.d.), bismuth subcitrate (300 mg q.d.s.), amoxicillin (500 mg q.d.s.) and levofloxacin (500 mg o.d.). Follow-up endoscopy with rapid urease test, histological examination and culture was performed at 6 weeks after the end of treatment to evaluate the response to therapy.

RESULTS

Helicobacter pylori was successfully eradicated in 31 out of 37 patients (84% by both intention-to-treat analysis and per-protocol analysis). All patients complied with the eradication therapies, and only seven patients (19%) complained of mild-to-moderate adverse events. Amoxicillin- and levofloxacin-resistant strains were observed in 17% and 22% of the patients, respectively. There were no significant differences between H. pylori eradication rates and antibiotic resistances.

CONCLUSIONS

The 10-day levofloxacin- and amoxicillin-based quadruple therapy is well tolerated and achieves a high eradication rate as a third-line empirical treatment for H. pylori infection.

Treatment strategy to eradicate Helicobacter pylori infection: impact of pharmacogenomics-based acid inhibition regimen and alternative antibiotics

The eradication rates of Helicobacter pylori by the triple therapy consisting of a proton pump inhibitor (PPI) and two antimicrobial agents are mainly influenced by bacterial susceptibility to antimicrobial agents and magnitude of acid inhibition during the treatment with a PPI. Acid inhibition during the treatment is affected by the dosing schemes of acid inhibitory drugs (i.e., PPI), genotypes of drug-metabolizing enzymes (i.e., CYP450 2C19), drug transporters (i.e., multi-drug resistant transporter-1) and inflammatory cytokines (i.e., IL-1 beta). Modification of dosing schedules of a PPI, such as frequent PPI dosing and concomitant dosing with a histamine 2-receptor antagonist, could overcome these genetics-related differences in therapeutic effectiveness. For attaining higher eradication rates, the tailored regimen based on the relevant pharmacogenomics is preferable.

Evolution of Helicobacter pylori therapy from a meta-analytical perspective

Even before the discovery of Helicobacter pylori as their cause, chronic gastritis and peptic ulcer disease were empirically treated with anti-infectious agents. However, it was not until that finding that an antibiotic approach began to be used systematically. The main aim of this article is to review the evolution of H. pylori therapy from a meta-analytical perspective. Initially, antibiotic monotherapy had a minor efficacy on H. pylori. Dual therapy including either bismuth compounds or proton-pump inhibitors (PPI) and one antibiotic also resulted in insufficient cure rates. Bismuth-based triple therapy (the first used) and PPI-based triple therapies (combined with two antibiotics, including amoxicillin, nitroimidazole, or clarithromycin) have been the most widely recommended. PPI-based regimens are superior to H2-antagonist-based ones. The influence of the type of PPI, the dose and the duration of the treatment will be discussed. Among the factors influencing the efficacy of therapy, resistance to clarithromycin and metronidazole are the most important risk factors for eradication failure. Several rescue therapies can be used. Bismuth-based quadruple therapy is effective, but the complexity of the regimen and the associated adverse effects limit the compliance. PPI-based triple therapy with amoxicillin and levofloxacin is at least equally effective and better tolerated.

Comparison of 1- and 2-week pantoprazole-based triple therapies in clarithromycin-sensitive and resistant cases

BACKGROUND

The objectives of this prospective study were: (i) to compare the efficacy of 1-week with 2-week pantoprazole-based triple therapy and (ii) to evaluate the impact of clarithromycin resistance on Helicobacter pylori (H. pylori) eradication rates.

METHODS

Eighty dyspeptic patients were randomly allocated to two groups. The first group (PAC-1, n=40) received pantoprazole 40 mg, amoxicillin 1000 mg, and clarithromycin 500 mg twice a day for one week, and the second group (PAC-2, n=40) received the same regimen for two weeks. Endoscopy was repeated one month after the end of the treatment.

RESULTS

DNA extraction for clarithromycin resistance could not be performed in seven cases. Five cases were lost to follow-up. Clarithromycin resistance was found to be 44.1% (15/34) in the PAC-1 group and 58.8% (20/34) in the PAC-2 group (p>0.05). Eradication was achieved in 16 (PP: 47.1%, ITT: 44.4%) and 25 (PP:73.5%, ITT: 67.6%) patients in the PAC-1 and PAC-2 groups, respectively (p>0.05). H. pylori was eradicated in 4 of 15 (PP: 26.7%, ITT: 26.7%) clarithromycin-resistant patients in the PAC-1 group and in 12 of 20 (PP: 60%, ITT: 60%) clarithromycin-resistant patients in the PAC-2 group (p>0.05). Among the clarithromycin-sensitive ones, eradication was achieved in 12 of 19 (PP: 63.2%, ITT: 57.1%) patients in the PAC-1 group and in 13 of 14 (PP: 92.8%, ITT: 76.5%) patients in the PAC-2 group (p>0.05).

CONCLUSION

Although the 2-week regimen of pantoprazole-based triple therapy was effective for H. pylori eradication in clarithromycin-sensitive cases, highly effective H. pylori eradication protocols are needed for clarithromycin-resistant ones.

Randomized comparison of two rescue therapies for Helicobacter pylori infection

BACKGROUND

Bismuth salts are not available worldwide. It remains unknown whether clarithromycin can replace bismuth salts as an adjuvant agent in the rescue regimens for Helicobacter pylori infection. We therefore designed the prospective study to compare the efficacies of two rescue therapies for H. pylori infection after standard triple therapies.

PATIENTS AND METHODS

Ninety-three patients who failed H. pylori eradication using proton pump inhibitor plus clarithromycin and amoxicillin were randomly assigned to undergo rescue therapy with esomeprazole, clarithromycin, tetracycline and metronidazole (ECTM group, n = 46) or esomeprazole, bismuth subcitrate, tetracycline and metronidazole (EBTM group, n = 47). Follow-up endoscopy was performed at 8 weeks after the end of treatment to assess the treatment response.

RESULTS

Intention-to-treat analysis demonstrated both groups had similar eradication rates (ECTM 74% vs. EBTM 77%; P = 0.76) and drug compliance (ECTM 94% vs. EBTM 96%; P = 0.68). However, the frequency of adverse events in the ECTM group was higher than that in EBTM group (ECTM 57% vs. EBTM 36%, P = 0.05). In the EBTM group, eradication rate of metronidazole-resistant strains was lower than that of metronidazole-susceptible strains (67%[8/12] vs. 100%[9/9], P = 0.05). However, eradication rates were similar between metronidazole-susceptible and metronidazole-resistant strains in ECTM group (69%[9/13] vs. 70%[7/10], P = 1.00).

CONCLUSIONS

The new ECTM second-line therapy can achieve similar eradication rate as standard EBTM therapy. It may be very useful in countries where bismuth salts are not available.

First-line eradication of H pylori infection in Europe: a meta-analysis based on congress abstracts, 1997-2004

AIM

To meta-analyse the European abstracts presented between 1997-2004 at the European H pylori Study Group, United European Gastroenterology Week meetings and World Congresses of Gastroenterology.

METHODS

The abstracts of randomized/controlled prospective studies were classified into groups based on first-line eradication schedules. The quality of the abstracts was checked by a validated score system. The pooled eradication rates (PER) and combined odds ratios (OR) were calculated and compared with the published meta-analyses.

RESULTS

The PER of proton pump inhibitor-based (PPI) one week triple therapies was 81.4% (confidence interval, 95% CI: 78.5-84.5). Ranitidine bismuth citrate-based (RBC) triple regimens have an efficiency rate of 78.5% (95% CI: 70.5%-84.3%) (P = 0.28 vs PPI). The OR for PPI effect vs RBC regimens was 1.1 (95% CI: 0.92-1.30). H(2) receptor antagonist-based triple therapies achieved 64.1% (95% CI: 52.6-75.6) (P = 0.02 < 0.05 vs PPI), the OR vs PPI regimens was 1.55 (95% CI: 0.72-3.78). PPI-based double combinations were less efficient than triple regimens (PER: 55.0%, OR: 4.90, 95% CI: 2.36-9.70). Quadruple regimens were successful in 82.6% (95% CI: 76.0-89.7), the OR vs triple therapies was 0.80 (0.62-1.03). Clarithromycin + amoxicillin or nitroimidazole combinations were efficient in 80.5% (95% CI: 77.2-84.2) and 83.8% (95% CI: 81.7-85.9), respectively. Amoxicillin + nitromidazole therapies eradicated the infection in 73.5% (66.6-78.5) (P = 0.01 < 0.05 vs clarithromycin-based regimens).

CONCLUSION

PPI/RBC-based triple therapies achieved comparable results with the meta-analyses. H(2)-receptor antagonists and PPI-based double combinations were less efficient. Triple and quadruple regimens were equally effective. Clarithromycin + either amoxicillin or nitroimidazole containing regimens were more effective than amoxicillin + nitroimidazole combinations. High quality congress abstracts constitutes a valuable pool of data which is suitable for meta-analytical workup.

A prospective randomized trial of esomeprazole- versus pantoprazole-based triple therapy for Helicobacter pylori eradication

OBJECTIVE

This prospective, randomized, controlled, head-to-head study was conducted to compare the efficacies of esomeprazole- and pantoprazole-based triple therapies for Helicobacter pylori eradication.

METHODS

From January 2002 to October 2003, 200 H. pylori-infected patients were randomly assigned to undergo twice daily treatment with esomeprazole 40 mg (n = 100) or pantoprazole 40 mg (n = 100) combined with clarithromycin 500 mg and amoxicillin 1 g for 1 wk (ECA and PCA groups, respectively). Follow-up endoscopy was performed at 8 wks after the end of treatment to assess the treatment response.

RESULTS

Intention-to-treat analysis demonstrated a significantly higher eradication rate for the ECA group than for the PCA group (94%vs 82%, respectively, p= 0.009). Per-protocol analysis also showed similar results (97%vs 84%, p= 0.003). Both groups had similar frequencies of adverse events (15%vs 24%) and drug compliance (97%vs 96%). Multivariate analysis disclosed that the use of esomeprazole (OR: 1.56, 95% CI, 1.11-2.19) and good compliance 7.39 (95% CI, 1.27-42.95) were independent predictors of treatment success. Alcohol drinking was an independent predictor of eradication failure (OR: 0.18; 95% CI, 0.06-0.54).

CONCLUSION

Esomeprazole-based triple therapy demonstrated a higher eradication rate than pantoprazole-based regimen. The differences in eradiation efficacies between the two study groups may be related to the more powerful acid inhibition effect and stronger anti-H. pylori activity of esomeprazole compared to pantoprazole.

Potent Gastric Acid Inhibition in Helicobacter pylori Eradication

At present, antisecretory drugs--foremost among them the proton pump inhibitors (PPIs)--represent a keystone in Helicobacter pylori eradication therapy. The present article shall first compare the role of PPIs as compared with histamine H2 receptor antagonists, both of them in the role of antibiotic-associated antisecretory therapy, and shall then address the contribution of each of the various PPIs that have been developed until the present time to the H. pylori eradication therapies. In summary, it may be concluded that PPIs are more effective overall than H2 receptor antagonists when the two groups of antisecretory drugs are given at the usual standard doses together with antibiotics with the intention of eradicating H. pylori infection. However, all PPIs (omeprazole, lansoprazole, pantoprazole, rabeprazole, and esomeprazole) are equivalent when given together with two antibiotics to cure the infection.

Epidemiology of non-Hodgkin's lymphoma (NHL): trends, geographic distribution, and etiology

While for most cancers incidence and mortality are decreasing, those of non-Hodgkin's lymphoma (NHL) are steadily increasing. Research to define reasons for this increase is extensive, but has not yet resolved them. We have conducted a literature analysis on trends regarding changes in the incidence, geographic distribution, and etiologic factors of NHL. From our own and previous analyses, an increasing NHL incidence at a rate of 3-4% per year was observed for the 1970s and 1980s. This stabilized in the 1990s, nevertheless still with an annual rise of 1-2%, resulting in almost a doubling of the NHL incidence. This rise has been noted worldwide, particularly in elderly persons >55 years. Concerning gender subgroups, a male predominance throughout all age groups is apparent. Although the NHL incidence has historically been higher in whites than blacks, disproportional increases have recently been observed in the latter group. Increases in high-grade NHL and extranodal disease are predominant. Differences in geographic distribution are striking for follicular lymphoma, which is more common in Western countries than elsewhere. Asians have higher rates of aggressive NHL, T-cell lymphomas, and extranodal disease. In the Middle East, high rates of intestinal extranodal disease are observed, whereas in Africa, endemic Burkitt's lymphoma accounts for a substantial proportion. Risks for developing NHL include immunosuppression and a causal link between infectious agents, and lymphomagenesis has also been determined, particularly for human T-cell leukemia/lymphoma virus type 1 (HTLV-1), Epstein-Barr virus (EBV), and Helicobacter pylori infections. Exposure to environmental agents and occupational risks have been studied; however, their significance is as yet uncertain.