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

Optimal therapy for Helicobacter pylori infections

Although Helicobacter pylori infection is both a common and a serious bacterial infection, antimicrobial therapies have rarely been optimized, are prescribed empirically, and provide inferior results compared with antimicrobial therapies for other common infectious diseases. The effectiveness of many of the frequently recommended H. pylori infection treatment regimens has been increasingly compromised by antimicrobial resistance. Regional data on the susceptibility of strains of H. pylori to available antimicrobials are sorely needed. Noninvasive molecular methods are possible to assess clarithromycin susceptibility in isolates obtained from stool specimens. As a general rule, clinicians should prescribe therapeutic regimens that have a ≥90% or, preferably, ≥95% eradication rate locally. If no available regimen can achieve a ≥90% eradication rate, clinicians should use the most effective regimen(s) available locally. Eradication of infection should always be confirmed after treatment in order to provide feedback regarding local effectiveness and an early warning of increasing resistance. In most regions of the world, four-drug treatment regimens, including a PPI plus three antimicrobials (clarithromycin, metronidazole/tinidazole and amoxicillin), or a PPI plus a bismuth plus tetracycline and metronidazole provide the best results. Standard triple therapy (a PPI, amoxicillin and clarithromycin) should now be avoided owing to increasing resistance to this treatment.

Helicobacter pylori infection and current clinical areas of contention

PURPOSE OF REVIEW

The indication for Helicobacter pylori (H. pylori) eradication has been extended to few extragastroduodenal diseases. Scientific rigor needs to be applied as the list of clinical manifestations potentially related to H. pylori has disproportionally grown to its scientific evidence. Some potential beneficial aspects of H. pylori in allergic diseases and in the context of obesity are critically addressed in this review. The main challenge, however, continues to be the prevention of gastric cancer by H. pylori eradication. Strategies for identification of individuals and populations at risk are reported as well. A final aspect is dedicated to novel treatment regimens for overcoming the increasing treatment failures with proton pump inhibitor-based triple standards.

RECENT FINDINGS

H. pylori infection is associated with some extragastric diseases such as idiopathic thrombocytic purpura and iron deficiency anemia that benefit from eradication therapy. The inverse relation of H. pylori prevalence and the increase in allergies and obesity, as reported from epidemiological studies, has prompted research for elucidating potential underlying pathophysiological mechanisms. Strategies for gastric cancer prevention include serological screening, which allow adopting eradication therapy in individuals at high risk. New treatments for H. pylori include sequential, bismuth-based quadruple and nonbismuth-based quadruple therapies.

SUMMARY

The main clinical challenge remains prevention of H. pylori-related diseases by effective treatment and screening procedures.

Pharmacologic aspects of eradication therapy for Helicobacter pylori Infection

The commonly used regimens for the eradication of Helicobacter pylori infection consist of administration of proton pump inhibitors (PPIs) and 1 to 3 antimicrobial agents, such as amoxicillin, clarithromycin, metronidazole, fluoroquinolone, or tetracycline. Each agent has its own pharmacologic characteristics. PPIs are metabolized by cytochrome P450 2C19 (CYP2C19), which is polymorphic. CYP2C19 genotypic differences in the pharmacokinetics and pharmacodynamics of PPIs influence the eradication rates of H pylori infection by PPI-containing regimens. Amoxicillin is a time-dependent antibiotic, whereas clarithromycin, metronidazole, tetracycline, and fluoroquinolone are not. The plasma half-life of antimicrobial agents also differs among these antibiotics. To achieve consistently high eradication rates, the eradication regimens must be designed based on a good understanding of the resistance patterns of the bacteria and the pharmacologic characteristics of the agents used for H pylori eradication therapy.

Treatment of Helicobacter pylori infection 2010

It is accepted that the success of Helicobacter pylori eradication treatment using standard triple therapy is declining. Resistance, particularly to clarithromycin, has been shown in numerous countries to be rising to a level where the use of standard triple therapy in its current form may no longer be justified. The two major factors influencing resistance are prior exposure to the antibiotic and compliance with therapy. Regimes based on bismuth and levofloxacin, which had previously been mainly second-line options, are now emerging as superior first-line options. Trials of sequential and concomitant therapies are also showing the usefulness of these treatments in different populations. Options for third and subsequent line therapies include furazolidone and rifabutin-based regimes. Susceptibility testing should be performed to maintain accurate data on resistance levels, and has also clinical utility in difficult to eradicate cases. None of these, however, will be successful unless compliance is improved upon. If compliance is assured and eradication confirmation pursued, it has been repeatedly illustrated that near full eradication is achievable.

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.

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.

Ten-day sequential therapy as first-line treatment for Helicobacter pylori infection in Korea: a retrospective study

BACKGROUND AND AIMS

The eradication rate of proton-pump inhibitor-based triple therapy for Helicobacter pylori infection is low due to increasing antibiotics resistance, especially clarithromycin. Recently, it was reported in Europe that a 10-day sequential strategy produced good outcomes. The aim of this study was to assess the efficacy of sequential therapy as first-line treatment for eradication of H. pylori in clinical practice in Korea.

MATERIALS AND METHODS

A total of 98 patients (mean age 55.2 years and male 47, female 51) with proven H. pylori infection received 10-day sequential therapy (20 mg of rabeprazole, and 1 g of amoxicillin, twice daily for the first 5 days, followed by 20 mg of rabeprazole, 500 mg of clarithromycin, and 500 mg of metronidazole, twice daily for the remaining 5 days). Eradication was evaluated 4 weeks later, after completion of treatment by 13(C)-urea breath testing. Eradication rates were calculated by intention-to-treat (ITT) and by per protocol (PP). Compliance and adverse events were also assessed in study group.

RESULTS

The eradication rate of sequential therapy was 91.8% (90/98) by ITT and same result was reported by PP analysis (89/97). The study group consisted of 66 H. pylori associated gastritis, 7 gastric ulcer, and 25 duodenal ulcer patients (67.3%, 7.1%, 25.5%, respectively). Mild adverse events happened frequently (21.4%) but the treatment was well tolerable. The most common adverse event was a bitter taste (9.2%) followed by nausea and diarrhea (4.1%).

CONCLUSIONS

Ten-day sequential therapy is found to effectively eradicate H. pylori infection as first-line treatment in Korea.

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.

Guidelines for the management of Helicobacter pylori infection in Japan: 2009 revised edition

BACKGROUND

Over the past few years, the profile of Helicobacter pylori infection has changed in Japan. In particular, the relationship between H. pylori and gastric cancer has been demonstrated more clearly. Accordingly, the committee of the Japanese Society for Helicobacter Research has revised the guidelines for diagnosis and treatment of H. pylori infection in Japan.

MATERIALS AND METHODS

Four meetings of guidelines preparation committee were held from July 2007 to December 2008. In the new guidelines, recommendations for treatment have been classified into five grades according to the Minds Recommendation Grades, while the level of evidence has been classified into six grades. The Japanese national health insurance system was not taken into consideration when preparing these guidelines.

RESULTS

Helicobacter pylori eradication therapy achieved a Grade A recommendation, being useful for the treatment of gastric or duodenal ulcer, for the treatment and prevention of H. pylori-associated diseases such as gastric cancer, and for inhibiting the spread of H. pylori infection. Levels of evidence were determined for each disease associated with H. pylori infection. For the diagnosis of H. pylori infection, measurement of H. pylori antigen in the feces was added to the tests not requiring biopsy. One week of proton-pump inhibitor-based triple therapy (including amoxicillin and metronidazole) was recommended as second-line therapy after failure of first-line eradication therapy.

CONCLUSION

The revised Japanese guidelines for H. pylori are based on scientific evidence and avoid the administrative restraints that applied to earlier versions.

High level of antimicrobial resistance in French Helicobacter pylori isolates

BACKGROUND

Helicobacter pylori is a human pathogen responsible for serious diseases including peptic ulcer disease and gastric cancer. The recommended triple therapy included clarithromycin but increasing resistance has undermined its effectiveness. It is therefore important to be aware of the local prevalence of antimicrobial resistance to adjust treatment strategy.

MATERIALS AND METHODS

Overall, 530 biopsies were collected between 2004 and 2007. The antimicrobial susceptibility of H. pylori was determined by E-test and molecular methods.

RESULTS

Among these, 138/530 (26%) strains were resistant to clarithromycin, 324/530 (61%) to metronidazole and 70/530 (13.2%) to ciprofloxacin. Whereas no resistance against amoxicillin and tetracycline was observed, only one strain was resistant to rifampicin. Compared to the patients never treated for H. pylori infection, the prevalence of resistance was significantly higher in patients previously treated (19.1% vs 68% for clarithromycin; 13.2% vs 53.3% for both clarithromycin and metronidazole). The trend analysis revealed an increase of primary resistance to ciprofloxacin between 2004 and 2005 (7.3%) vs 2006-2007 (14.1%) (p = .04) and the secondary resistance reached 22.7% in 2007. Interestingly, 27 biopsies (19.6%) contained a double population of clarithromycin-susceptible and -resistant strains.

CONCLUSIONS

The reported high prevalence of clarithromycin and multiple resistances of H. pylori suggest that the empiric therapy with clarithromycin should be abandoned as no longer pretreatment susceptibility testing has assessed the susceptibility of the strain. As culture and antibiogram are not routinely performable in most clinical laboratories, the use of molecular test should be developed to allow a wide availability of pretreatment susceptibility testing.

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.

Annual change of primary resistance to clarithromycin among Helicobacter pylori isolates from 1996 through 2008 in Japan

BACKGROUND

Recent studies have shown that the combination of proton pump inhibitor, amoxicillin and clarithromycin is one of the best choices for Helicobacter pylori eradication therapy. However, increasing number of cases of H. pylori infection showing resistance to clarithromycin therapy has been reported and this is currently the main cause of eradication failure. We investigated the annual changes of the antimicrobial susceptibility to clarithromycin, amoxicillin and minocycline during a period of 12 years in Japan.

METHODS

This study comprised 3521 patients (mean age (SD), 55.4 (13.7) years-old, 2467 males and 1054 females) positive for H. pylori as assessed by microaerobic bacterial culture from 1996 through 2008. All patients were previously untreated for H. pylori and were enrolled in the study to assess primary resistance to the three antibiotics.

RESULTS

The overall primary resistance to clarithromycin, amoxicillin and minocycline were 16.4%, (577/3521), 0.03% (1/3521) and 0.06% (2/3521), respectively. From 1996 through 2004, the resistance rate to clarithromycin increased gradually to approximately 30% and then it remained without marked fluctuation since 2004. Analysis by gender showed a significant increase (p < .0001) in resistance rate to clarithromycin among females (217/1057, 20.6%) compared to males (360/2467, 14.6%). Analysis by age, disclosed significantly (p < .0001) higher resistance rate to clarithromycin in patients of more than 65-years-old compared to the younger population.

CONCLUSIONS

The resistance rate of H. pylori infection to clarithromycin in Japan has increased gradually to approximately 30% from 1996 through 2004, and remained unchanged since 2004. Elderly and females were at high risk of having resistance to clarithromycin. Our results suggested that the level of clarithromycin resistance in Japan has now risen to the point where it should no longer be used as empiric therapy.

Treatment of Helicobacter pylori infection

This article aims to examine current best practice in the field reference to first-line, second-line, rescue and emerging treatment regimens for Helicobacter pylori eradication. The recommended first-line treatment in published guidelines in Europe and North American is proton pump inhibitor combined with amoxicillin and clarithromycin being the favoured regimen. Rates of eradication with this regimen however are falling alarmingly due to a combination of antibiotic resistance and poor compliance with therapy. Bismuth based quadruple therapies and levofloxacin based regimes have been shown to be effective second line regimens. Third-line options include regimes based on rifabutin or furazolidone, but susceptibility testing is the most rational option here, but is currently not used widely enough. Sequential therapy is promising but needs further study and validation outside of Italy. Although the success of first line treatments is falling, if compliance is good and a clear treatment paradigm adhered to, almost universal eradication rates can still be achieved. If compliance is not achievable, the problem of antibiotic resistance will continue to beset any combination of drugs used for H. pylori eradication.