Therapy for Helicobacter pylori infection can be improved: sequential therapy and beyond

Geographic map and evolution of primary Helicobacter pylori resistance to antibacterial agents

Antibiotic resistance in Helicobacter pylori is the major cause of eradication failure. Primary H. pylori susceptibility patterns, however, are becoming less predictable. Currently, high (> or =20%) clarithromycin resistance rates have been observed in the USA and in developed countries in Europe and Asia, while the highest (> or =80%) metronidazole-resistance rates have been reported in Africa, Asia and South America. Primary quinolone-resistance rates of 10% or more have already been reported in developed countries in Europe and Asia. Primary amoxicillin resistance has been low (0 to <2%) in Europe but higher (6-59%) in Africa, Asia and South America. Similarly, tetracycline resistance has been absent or low (<5%) in most countries and higher (9-27%) in Asia and South America. The increasing clarithromycin and quinolone resistance, and multidrug resistance detected in 0 to less than 5% in Europe and more often (14.2%) in Brazil are worrying. Growing resistance often parallels national antibiotic consumption and may vary within patient groups according to the geographic region, patient's age and sex, type of disease, birthplace, other infections and other factors. The geographic map and evolution of primary H. pylori resistance are clinically important, should be considered when choosing eradication regimens, and should be monitored constantly at national and global levels in an attempt to reach the recently recommended goal of eradication of more than 95%.

High efficacy of 14-day triple therapy-based, bismuth-containing quadruple therapy for initial Helicobacter pylori eradication

BACKGROUND

The success rate of currently recommended 7-day triple therapy with a PPI plus amoxicillin and clarithromycin has fallen into the unacceptable range. It is urgent to look for a new strategy to treat the infection of Helicobacter pylori.

AIMS

To observe the efficacy of triple therapy-based, bismuth-containing quadruple therapy for H. pylori treatment.

METHODS

A total of 160 patients with functional dyspepsia who were Hp+ were randomly assigned into two groups. Regimen: Omeprazole 20 mg, Amoxicillin 1.0 g, Clarithromycin 500 mg and Bismuth Potassium Citrate 220 mg, twice a day. Eighty patients received 7-day quadruple therapy and 80 patients received the same therapy for 14 days. Six weeks after treatment, H. pylori eradication was assessed by (13)C-urea breath test. Minimal inhibitory concentrations of metronidazole, clarithromycin and amoxicillin of clinical isolates were determined by the twofold agar dilution method.

RESULTS

Fourteen-day therapy led to a significant increase of H. pylori eradication success when compared to 7-day therapy in the intention-to-treat analysis (93.7 vs 80.0%; p = .01), and the per-protocol analysis (97.4 vs 82.0%; p = .0016). The H. pylori resistance rates to metronidazole, clarithromycin and amoxicillin were 42.1, 18.0 and 0%. Fourteen-day therapy was significantly more effective in patients with clarithromycin-resistant strains. Incidences of adverse events were comparable.

CONCLUSIONS

Addition bismuth and prolonging treatment duration can overcome H. pylori resistance to clarithromycin and decrease the bacterial load. Fourteen-day triple therapy-based, bismuth-containing quadruple therapy achieved ITT success rate 93% and could be recommended as the first line eradication regimen.

Sequential therapy for Helicobacter pylori eradication: a critical review

BACKGROUND

Alternative treatment regimens for standard triple therapy are urgently needed.

AIM

To critically review the evidence on the role of "sequential" regimen for the treatment of Helicobacter pylori infection.

METHODS

Bibliographical searches were performed in MEDLINE and international congresses.

RESULTS

Several pooled-data analyses and meta-analyses have demonstrated that sequential regimen is more effective than standard triple therapy. Sequential therapy is not affected by bacterial (CagA status, infection density) and host factors (underlying disease, smoking). Clarithromycin resistance seems to be the only factor reducing their efficacy. However, even in these patients, an acceptable >75% eradication rate can be achieved. Unfortunately, almost all the studies have been performed in Italy. Whether it is necessary to provide the drugs sequentially or if the 4 components of sequential therapy can be given concurrently is unclear. Nonbismuth quadruple therapy seems to be an effective and safe alternative to triple therapy and is less complex than sequential therapy.

CONCLUSIONS

Sequential therapy is a novel promising treatment approach that deserves consideration as a treatment strategy for H. pylori infection. However, further robust assessment across a much broader range of patients is required before sequential therapy could supplant existing treatment regimens and be generally recommended in clinical practice.

Comparison of the efficacy of the two tetracycline-containing sequential therapy regimens for the eradication of Helicobacter pylori: 5 days versus 14 days amoxicillin

AIM

To compare the efficacy of 14-day and 5-day amoxicillin treatment on the eradication rate during tetracycline containing sequential H. pylori therapy, and also to compare the eradication rate of this regimen with those used in similar studies performed in Turkey.

METHOD

This study included 112 patients infected with H. pylori that were randomized into 2 groups. In group A, patients (n = 56) received pantoprazole (40 mg BID) and amoxicillin (1 g BID) for 5 days, followed by pantoprazole (40 mg BID), tetracycline (500 mg QID), and metronidazole (500 mg TID) for the remaining 9 days. In group B, patients (n = 56) received pantoprazole (40 mg BID) and amoxicillin (1 g BID) for 5 days, followed by pantoprazole (40 mg BID), tetracycline (500 mg QID), metronidazole (500 mg TID), and amoxicillin (1 g BID) for the remaining 9 days. Eradication rates were calculated using both intention-to-treat (ITT) and per-protocol (PP) analyses.

RESULTS

In all, 112 patients were subjected to ITT analysis and 109 patients completed the study. In group A, H. pylori eradication was achieved in 46 (82.1%) of the 56 patients included in the ITT analysis and in 46 (83.6%) of the 55 patients included in the PP analysis. In group B, H. pylori eradication was achieved in 44 (78.57%) of the 56 patients included in the ITT analysis and in 44 (81.48%) of the 54 patients included in the PP analysis (Table 2). The eradication rates were not statistically significant between the 2 groups (p > .005).

CONCLUSION

Extended duration of amoxicillin treatment during the entire tetracycline containing sequential therapy period did not improve the H. pylori eradication rate. As a consequence, sequential therapy using 5-day amoxicillin is an acceptable first-line therapy option for the eradication of H. pylori in Turkey.

The sequential therapy regimen for Helicobacter pylori eradication

IMPORTANCE OF THE FIELD

Standard triple therapy (STT) is the most used treatment for Helicobater pylori infection. The prevalence of antibiotic resistance has increased substantially in recent years and there has been a corresponding decrease in efficacy.

AREAS COVERED IN THIS REVIEW

Bibliographical searches were performed in MEDLINE and international congresses up to 2009 for 'Helicobacter pylori' AND 'sequential regimen/therapy'.

WHAT THE READER WILL GAIN

Several meta-analyses have demonstrated that sequential therapy (SQT) is more effective than STT. SQT is not affected by bacterial and host factors that have, until now, predicted the outcome of STT. Primary clarithromycin resistance is the only factor reducing the efficacy of SQT; however, even in these patients an acceptable > 75% eradication can be achieved. So far, almost all the studies have been performed in Italy. The advantages of SQT over STT should be confirmed in different countries. Whether it is necessary to provide the drugs sequentially or if the four components of SQT can be given concurrently is unclear.

TAKE HOME MESSAGE

SQT is a promising new treatment approach that deserves consideration as a treatment strategy for H. pylori infection. However, further robust assessment across a much broader range of patients is required before SQT could supplant existing treatment regimens and be generally recommended in clinical practice.

Clinical practice: diagnosis and evaluation of dyspepsia

The main issue regarding the approach to the patient with uninvestigated dyspepsia is whether the symptoms are the result of an important clinical illness, which then determines the appropriate management strategy for the treatment of the symptoms. An initial trial of empiric antisecretory drugs is recommended for those without Helicobacter pylori infection and no alarm symptoms, whereas H. pylori eradication is recommended for those with an active H. pylori infection. Treatment expectations for H. pylori infections should theoretically be similar to other common infectious diseases. In most regions, clarithromycin resistance has undermined traditional triple therapy so that it is no longer a suitable choice as an empiric therapy. Four drug therapies, such as sequential, concomitant, and bismuth-quadruple therapy are generally still acceptable choices as empiric therapies. Posteradication testing is highly recommended to provide early identification of otherwise unrecognized increasing antimicrobial resistance. However, despite the ability to successfully cure H. pylori infections, a symptomatic response can be expected in only a minority of those with dyspepsia not associated with ulcers (so called nonulcer dyspepsia). Overall, from the patients stand point, symptomatic relief is often difficult to achieve and physicians must rely on reassurance along with empiric and individualized care.

Sequential and concomitant therapy with four drugs is equally effective for eradication of H pylori infection

BACKGROUND & AIMS

Sequential therapy with a proton pump inhibitor (PPI) and amoxicillin followed by a PPI, clarithromycin, and an imidazole agent reportedly have a better rate of curing Helicobacter pylori infection than PPI, amoxicillin, and clarithromycin triple therapy. The concomitant administration of these 4 drugs (concomitant therapy) is also an effective treatment strategy. We compared the efficacies of sequential and concomitant therapy and analyzed the effects of antibiotic resistance in patients with H pylori infection.

METHODS

In a randomized trial of 232 H pylori-infected patients from 3 hospitals in Kaohsiung, Taiwan, patients were given 10 days of sequential (n = 115) or concomitant (n = 117) therapy. H pylori status was confirmed by endoscopy or urea breath test.

RESULTS

Intention-to-treat analysis demonstrated similar eradication rates for sequential (92.3%; 95% confidence interval [CI], 87.5%-97.1%) and concomitant therapy (93.0%; 95% CI, 88.3%-97.7%)(P = .83). Per-protocol eradication results were similar for sequential (93.1%; 95% CI, 90.7%-95.5%) and concomitant therapy (93.0%; 95% CI, 88.3%-97.7%) (P = .99). Univariate analysis showed that compliance and resistance to clarithromycin were independent determinants of eradication. Dual resistance did not influence the level of eradication in the concomitant group, but significantly affected that of the sequential therapy group. Clarithromycin resistance was less frequent than expected.

CONCLUSIONS

Sequential or concomitant therapy with a PPI, amoxicillin, clarithromycin, and an imidazole agent are equally effective and safe for eradication of H pylori infection. Resistance to clarithromycin, compliance, and adverse events reduced the level of eradication. Concomitant therapy may be more suitable for patients with dual resistance to antibiotics.

Influence of inflammatory cytokine polymorphisms on eradication rates of Helicobacter pylori

Pro-inflammatory cytokines and anti-inflammatory cytokines are produced in gastric mucosa from inflammatory cells activated by Helicobacter pylori (H. pylori) infection. Of the inflammatory cytokines, interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha have a potent inhibitive effect on gastric acid production. Polymorphisms in these genes are associated with individual differences in cytokine messenger RNA levels, which result in different gastric mucosal inflammation, different acid inhibition and different gastroduodenal disease risks in response to H. pylori infection. The sustained higher intragastric pH during an eradication therapy is known to be one of the therapeutic determinants of the H. pylori eradication as well as antibiotics resistance and poor compliance. The IL-1B-511 polymorphism is related to eradication rate, and, in combined analysis of previous reports, the eradication rate in patients with the IL-1B-511 C/C genotype (77.4%, 209/270), low IL-1beta producer genotype, is lower than that of the IL-1B-511 C/T and T/T genotypes (87.2%, 631/724) (Odds ratio for eradication failure: 1.98, 95% confidence interval: 1.38-2.84, P = 0.0002). Moreover, the odds ratio of combined CYP2C19 rapid metabolizer-IL-1B-511 C/C type for eradication failure is 11.15 (5.23-23.78) times that of the CYP2C19 poor metabolizer-IL-1B-511 non-C/C type. However, there is no positive data indicating the role of other inflammatory cytokine polymorphisms (e.g. IL-1RN, TNF-A or IL-10) in eradication therapy. Nevertheless, the studies show that inflammatory cytokine polymorphisms, especially the IL-1B-511 T/T genotype, are the determinants of eradication by affecting gastric acid secretion and mucosal inflammation. Therefore, the tailored eradication therapy, considering inflammatory cytokine polymorphisms, may be effective for the higher eradication rates.

Refractory peptic ulcer disease

Refractory PUD is a diagnostic and therapeutic challenge. Optimal management of severe or refractory PUD requires a multidisciplinary team approach, using primary care providers, gastroenterologists, and general surgeons. Medical management has become the cornerstone of therapy. Identification and eradication of H pylori infection combined with acid reduction regimens can heal ulceration and also prevent recurrence. Severe, intractable or recurrent PUD and associated complications mandates a careful and methodical evaluation and management strategy to determine the potential etiologies and necessary treatment (medical or surgical) required.

Specific therapeutic schemes of omeprazole affect the orientation of Helicobacter pylori

Until now, it has been unclear how proton pump inhibitors (PPIs) support Helicobacter pylori therapy. We tested whether the PPI omeprazole acts on the spatial orientation of H. pylori in the gastric mucus of infected Mongolian gerbils. Following repetitive PPI administration once daily but not following single doses or administration every 8 h, the bacterial spatial distribution changed, indicating a loss of orientation. Therefore, the therapeutic scheme of PPI administration may affect efficiency of treatment.

Meta-analysis: four-drug, three-antibiotic, non-bismuth-containing "concomitant therapy" versus triple therapy for Helicobacter pylori eradication

BACKGROUND

Low success rates with triple therapy for Helicobacter pylori infections have prompted search for alternatives. In one, a proton-pump inhibitor (PPI) and amoxicillin was followed by the PPI plus clarithromycin and a nitroimidazole (sequential therapy); in another, these four drugs were given concomitantly (concomitant therapy).

AIM

To compare concomitant therapy with standard triple therapy for H. pylori infection.

METHODS

By searching PubMed, EMBASE, the Cochrane Central Register of Controlled Trials and abstracts of major gastrointestinal meeting, two independent reviewers systemically identified randomized controlled trials (RCT) comparing concomitant quadruple to standard triple therapies as well as studies reporting eradication rates of concomitant quadruple therapy in treatment of H. pylori. Pooled eradication rates and odds ratios (OR) with 95% confidence intervals (CI) were calculated, and univariable metaregression analysis for all extracted variables was conducted.

RESULTS

We identified nine studies (10 treatment arms) including five qualifying RCTs (576 subjects) comparing concomitant (293 subjects, duration 3 to 5 days) and triple therapy (283 subjects, duration 5 to 10 days) and four other studies evaluating concomitant therapy (478 subjects, duration 3 to 7 days). Pooled estimates of the five RCTs showed superiority of concomitant therapy over triple therapy; with intention-to-treat) pooled OR of 2.86 (95% CI: 1.73-4.73) and per-protocol (PP) pooled OR of 3.52 (95% CI: 1.95-6.38). Considering all 10 treatment arms, the ITT eradication rate was 89.7% (95% CI: 86.8-92.1%) and PP was 92.9% (95% CI: 90.2-94.8%).

CONCLUSION

Concomitant therapy appears to be an effective alternative to triple therapy and is less complex than sequential therapy.

Impact of quadruple regimen of clarithromycin added to metronidazole-containing triple therapy against Helicobacter pylori infection following clarithromycin-containing triple-therapy failure

BACKGROUND

The establishment of an optimal second-line regimen for Helicobacter pylori infection is required. Although quadruple therapy should overcome resistance to either clarithromycin or metronidazole, the effects of a quadruple regimen in second-line therapy are unknown. This study aims to evaluate the efficacy of triple therapy composed of proton pump inhibitor/amoxicillin plus metronidazole with the combined additive effects of clarithromycin as a second-line quadruple therapy against H. pylori infection.

MATERIALS AND METHODS

Participants were 104 patients in whom first-line therapy containing proton pump inhibitor-amoxicillin-clarithromycin failed. Before starting second-line therapy, patients underwent endoscopy to obtain H. pylori strain for antibiotic susceptibility tests. Patients were randomized to receive rabeprazole (10 mg), amoxicillin (750 mg), and metronidazole (250 mg), either with clarithromycin (200 mg; RAMC group) or without (RAM group); all treatments were administered twice daily for 7 days. H. pylori eradication was confirmed by (13)C-urea breath tests performed 2 to 3 months post-therapy.

RESULTS

As shown by intention-to-treat/per-protocol analyses, the cure rates for H. pylori infection were 88.5%/93.9% and 82.7%/84.3% for the RAMC and RAM groups. Although the study probably had an insufficient power to show a significant difference between the cure rates of the two regimens, the eradication rates showed a clear trend in favor of the RAMC group. There were no severe side-effects in any group.

CONCLUSIONS

In Japan, the RAMC regimen is thought to be a promising alternative strategy for second-line eradication of H. pylori infection.

Meta-analysis: four-drug, three-antibiotic, non-bismuth-containing "concomitant therapy" versus triple therapy for Helicobacter pylori eradication

BACKGROUND

Low success rates with triple therapy for Helicobacter pylori infections have prompted search for alternatives. In one, a proton-pump inhibitor (PPI) and amoxicillin was followed by the PPI plus clarithromycin and a nitroimidazole (sequential therapy); in another, these four drugs were given concomitantly (concomitant therapy).

AIM

To compare concomitant therapy with standard triple therapy for H. pylori infection.

METHODS

By searching PubMed, EMBASE, the Cochrane Central Register of Controlled Trials and abstracts of major gastrointestinal meeting, two independent reviewers systemically identified randomized controlled trials (RCT) comparing concomitant quadruple to standard triple therapies as well as studies reporting eradication rates of concomitant quadruple therapy in treatment of H. pylori. Pooled eradication rates and odds ratios (OR) with 95% confidence intervals (CI) were calculated, and univariable metaregression analysis for all extracted variables was conducted.

RESULTS

We identified nine studies (10 treatment arms) including five qualifying RCTs (576 subjects) comparing concomitant (293 subjects, duration 3 to 5 days) and triple therapy (283 subjects, duration 5 to 10 days) and four other studies evaluating concomitant therapy (478 subjects, duration 3 to 7 days). Pooled estimates of the five RCTs showed superiority of concomitant therapy over triple therapy; with intention-to-treat) pooled OR of 2.86 (95% CI: 1.73-4.73) and per-protocol (PP) pooled OR of 3.52 (95% CI: 1.95-6.38). Considering all 10 treatment arms, the ITT eradication rate was 89.7% (95% CI: 86.8-92.1%) and PP was 92.9% (95% CI: 90.2-94.8%).

CONCLUSION

Concomitant therapy appears to be an effective alternative to triple therapy and is less complex than sequential therapy.

Meta-analysis: four-drug, three-antibiotic, non-bismuth-containing "concomitant therapy" versus triple therapy for Helicobacter pylori eradication

BACKGROUND

Low success rates with triple therapy for Helicobacter pylori infections have prompted search for alternatives. In one, a proton-pump inhibitor (PPI) and amoxicillin was followed by the PPI plus clarithromycin and a nitroimidazole (sequential therapy); in another, these four drugs were given concomitantly (concomitant therapy).

AIM

To compare concomitant therapy with standard triple therapy for H. pylori infection.

METHODS

By searching PubMed, EMBASE, the Cochrane Central Register of Controlled Trials and abstracts of major gastrointestinal meeting, two independent reviewers systemically identified randomized controlled trials (RCT) comparing concomitant quadruple to standard triple therapies as well as studies reporting eradication rates of concomitant quadruple therapy in treatment of H. pylori. Pooled eradication rates and odds ratios (OR) with 95% confidence intervals (CI) were calculated, and univariable metaregression analysis for all extracted variables was conducted.

RESULTS

We identified nine studies (10 treatment arms) including five qualifying RCTs (576 subjects) comparing concomitant (293 subjects, duration 3 to 5 days) and triple therapy (283 subjects, duration 5 to 10 days) and four other studies evaluating concomitant therapy (478 subjects, duration 3 to 7 days). Pooled estimates of the five RCTs showed superiority of concomitant therapy over triple therapy; with intention-to-treat) pooled OR of 2.86 (95% CI: 1.73-4.73) and per-protocol (PP) pooled OR of 3.52 (95% CI: 1.95-6.38). Considering all 10 treatment arms, the ITT eradication rate was 89.7% (95% CI: 86.8-92.1%) and PP was 92.9% (95% CI: 90.2-94.8%).

CONCLUSION

Concomitant therapy appears to be an effective alternative to triple therapy and is less complex than sequential therapy.

High-dose versus standard-dose PPI in triple therapy for Helicobacter pylori eradication

Empiric clarithromycin-containing triple therapies for eradication of Helicobacter pylori do not reliably produce a >/=80% success rate on an intention-to-treat basis. This lack of adequate treatment response is primarily because of clarithromycin resistance. This commentary discusses the findings of a meta-analysis by Villoria et al. that investigated whether a triple therapy containing a high-dose PPI and clarithromycin plus either amoxicillin or tinidazole improves the success rate of H. pylori eradication compared with a triple therapy that contains a standard-dose PPI. The mean intention-to-treat cure rates were greater in patients who used the high-dose PPI regimen compared with the standard-dose regimen (82% vs 74%, respectively). However, the actual cure rates of these studies were poor and the improvements were unlikely to be clinically significant. The prevalence of clarithromycin resistance in most of the world is such that clarithromycin-containing triple therapy should not be used empirically. Alternatives include sequential or concomitant therapy and bismuth-containing quadruple therapies.

Efficient identification and evaluation of effective Helicobacter pylori therapies

Annually hundreds if not thousands of patients fail empiric H. pylori eradication therapy. Failure occurs in part because routine post treatment testing, which provides an early warning of increasing antibiotic resistance, is not universally done and physicians are generally unaware that cure rates with legacy triple therapy (a proton-pump inhibitor, amoxicillin, and clarithromycin) in most places has fallen below 80%. We propose first, institution of routine post eradication testing and second, abandonment of the "better than another therapy" approach to separating acceptable from unacceptable therapies. Instead, we propose using results-based outcomes (ie, >95% cure rates). H. pylori should be evaluated as other infectious diseases (ie, few would compare a new antibiotic for pneumonia with the previous best choice whose effectiveness was now impaired because of resistance). Randomized comparisons should be restricted to studies designed to improve (eg, simplify or reduce costs) high cure rate therapies while maintaining efficacy. We also discuss potential ethical issues such as those including known or suspected low cure rate therapies. Legacy therapies cannot be identified as "approved" or "recommended" even if both statements were true. Instead patients and ethics boards must receive "full disclosures" both before and during studies that include all that might affect a patient's decision to enter or to continue. Finally, we provides advice regarding trial design using "best shot" pilot studies to efficiently identify tentative effective regimens which are then confirmed in randomized trials all the while minimizing patient risks and drug exposure.

Virulence factor genotypes of Helicobacter pylori affect cure rates of eradication therapy

The cure rates of Helicobacter pylori infection by using a combination of a proton pump inhibitor (PPI) and antimicrobial agents are mainly influenced by bacterial susceptibility to antimicrobial agents and the magnitude of acid inhibition during the treatment. Currently used empirical triple therapies do not reliably produce a > or =80% cure rate on an intention-to-treat basis. Therefore, tailored regimens based on relevant microbiological findings and pharmacogenomics are recommended for attaining an acceptable > or =95% cure rate. Recently, virulence factors of H. pylori, such as cagA and vacA, are reported to be major factors determining the cure rates. Individuals infected with strains with cagA-negative and vacA s2 genotypes have significantly increased risk of eradication failure of H. pylori infection. These virulence factors enhance gastric mucosal inflammation and are associated with the development of peptic ulcer and gastric cancer. H. pylori virulence factors induce proinflammatory cytokines, such as interleukin (IL)-1, IL-8, and tumor necrosis factor (TNF)- which influence mucosal inflammation and/or gastric acid secretion. When physicians select an H. pylori eradication regimen with an acceptable cure rate, they might need to consider H. pylori virulence factors, especially cagA and vacA.

[The new aspects of the eradication of Helicobacter pylori and the importance of bacterial resistance]

The first line treatment of Helicobacter pylori infection is a 7-day PPI-based (PPI+clarithromycin+amoxycillin or metronidazole) combined therapy. Success of first eradication attempts in the literature is around 80-90%, while in Hungary 75%. Repeated eradication is needed in 10-25% of cases. The second and third line treatments are successful only in 36% and 20% of cases. Treatment failure is increasing worldwide with the higher rates of bacterial, especially clarithromycin resistance. Patients' noncompliance, pharmacogenetic and pharmacokinetic properties of the applied drugs are important as well. The eradication success rates are unacceptable in populations with higher metronidazole and clarithromycin resistance, that is why there is a need for newer combinations. A possible solution is the application of sequential therapy, or using newer antibiotics (levofloxacin). The importance of new natural substances (lactoferrin, probiotics, plant drugs) must be further investigated.