'Rescue' therapy with rifabutin after multiple Helicobacter pylori treatment failures

Efficacy and safety of rabeprazole, amoxicillin, and gatifloxacin after treatment failure of initial Helicobacter pylori eradication

OBJECTIVES

To evaluate the efficacy of a 7-day regimen of gatifloxacin (400 mg daily), amoxicillin (1 g twice a day), and rabeprazole (20 mg twice a day) in the secondary eradication of Helicobacter pylori infection.

METHODS

Eligible patients with persistent infection following one or more conventional clarithromycin-containing triple therapies were enrolled in this open-label trial. Eradication of infection was documented by (14)C-urea breath test a minimum of 4 weeks after therapy and 2 weeks off any acid suppressive therapy. Culture of H. pylori and in vitro susceptibility testing to amoxicillin, clarithromycin, and gatifloxacin was done in cases of failed eradication.

RESULTS

A total of 45 patients (22 females:23 males; mean age 44.5 +/- 13 years) were enrolled. Eradication occurred in 38 patients [both per-protocol (PP) and intention-to-treat analysis: 84.4%; 95% CI: 74-95%]. No significant adverse effects were reported. In vitro susceptibility testing showed no secondary resistance to gatifloxacin or amoxicillin in any of the seven nonresponders. Smoking, age, and sex were not predictors of potential eradication failure.

CONCLUSIONS

A 7-day regimen of gatifloxacin, rabeprazole, and amoxicillin is effective after failed eradication therapy for H. pylori and does not appear to result in secondary resistance. This combination is simple, well tolerated, and may lead to higher compliance and lower costs.

Randomized trial of rifabutin-based triple therapy and high-dose dual therapy for rescue treatment of Helicobacter pylori resistant to both metronidazole and clarithromycin

BACKGROUND

The clinical management of Helicobacter pylori infected patients who failed standard eradication therapies remains a challenge.

AIM

To investigate the efficacy of rifabutin-based triple therapy and high-dose dual therapy for rescue treatment of H. pylori, and the correlation between cytochrome P450 2C19 (CYP2C19) polymorphisms and treatment outcome.

METHODS

Patients infected with H. pylori resistant to both metronidazole and clarithromycin (n = 145) were randomized to either esomeprazole 20 mg, rifabutin 150 mg and amoxicillin 1 g, each given b.d. for 7 days (ERA), or to omeprazole 40 mg and amoxicillin 1000 mg, each given t.d.s. for 14 days (OA). Crossover therapy was offered in cases of persistent infection. CYP2C19 polymorphisms were determined by polymerase chain reaction restriction fragment length polymorphism.

RESULTS

Intention-to-treat and per-protocol eradication rates were: ERA 74% (62.4-83.6) and 78% (66.7-87.3); high-dose OA 70% (57.5-79.7) and 75% (62.5-84.5). Crossover therapy was successful in seven of 10 patients with ERA and in eight of 10 patients with OA. Premature discontinuation of treatment occurred in 2% and 5% of patients, respectively. There was only a non-significant trend to lower eradication rates in homozygous extensive metabolizers.

CONCLUSIONS

Triple therapy with esomeprazole, rifabutin and amoxicillin and high-dose omeprazole/amoxicillin are comparable and effective and safe for rescue therapy of H. pylori regardless of the patient's CYP2C19 genotype.

Third-line rescue therapy for Helicobacter pylori infection

H pylori gastric infection is one of the most prevalent infectious diseases worldwide. The discovery that most upper gastrointestinal diseases are related to H pylori infection and therefore can be treated with antibiotics is an important medical advance. Currently, a first-line triple therapy based on proton pump inhibitor (PPI) or ranitidine bismuth citrate (RBC) plus two antibiotics (clarithromycin and amo-xicillin or nitroimidazole) is recommended by all consensus conferences and guidelines. Even with the correct use of this drug combination, infection can not be eradicated in up to 23% of patients. Therefore, several second line therapies have been recommended. A 7 d quadruple therapy based on PPI, bismuth, tetracycline and metronidazole is the more frequently accepted. However, with second-line therapy, bacterial eradication may fail in up to 40% of cases. When H pylori eradication is strictly indicated the choice of further treatment is controversial. Currently, a standard third-line therapy is lacking and various protocols have been proposed. Even after two consecutive failures, the most recent literature data have demonstrated that H pylori eradication can be achieved in almost all patients, even when antibiotic susceptibility is not tested. Different possibilities of empirical treatment exist and the available third-line strategies are herein reviewed.

[Helicobacter pylori resistance: who needs what treatment?]

The standard treatment recommended for eradication of Helicobacter pylori is a combination of three drugs for seven days: one proton pump inhibitor at a double dose and two antibiotics. The high risk of failure - on the order of 30% - justifies routine testing to verify eradication after this first treatment. Verification is most often conducted with a urea breath test, more rarely by endoscopy when endoscopy or gastric histology is otherwise necessary. When eradication fails, longer multidrug treatment with different antibiotics is proposed. The failure rate after second-line treatment is 9-10%. If a third treatment is necessary, bacterial culture is recommended to select antibiotics on the basis of the antibiotic susceptibility testing.

Efficacy and safety of rifabutin-containing 'rescue therapy' for resistant Helicobacter pylori infection

BACKGROUND

Current 'rescue' therapies provide inadequate Helicobacter pylori eradication rates because of antibiotic resistance.

AIM

To test the efficacy of a modified triple regimen combining rifabutin, pantoprazole and amoxicillin as rescue therapy for patients in whom eradication of H. pylori had failed standard clarithromycin-based triple therapy.

METHODS

One hundred and thirty patients (mean age 51.7 +/- 14.8 years) who had failed one or more eradication attempts with omeprazole, clarithromycin and amoxicillin were treated for 12 days with rifabutin 150 mg daily, amoxicillin 1 g or 1.5 g t.d.s, and pantoprazole 80 mg t.d.s.

RESULTS

The intention-to-treat and per-protocol eradication rates were 90.8/90.8%. Metronidazole or/and clarithromycin resistance had no significant impact on H. pylori eradication rates. A higher overall eradication rate of 96.6% (95% CI: 92.1-101%) was obtained in patients treated with a regimen containing 1.5 g amoxicillin t.d.s compared with 90.7% (95% CI: 82-98.6%) using a regimen with 1 g amoxicillin t.d.s but the difference was not significant. Side-effects reported in 40% of patients were mild.

CONCLUSION

A 12-day course of low dose of rifabutin with an increased dose of amoxicillin and pantoprazole is well-tolerated and highly effective against dual-resistant H. pylori infection after failure of triple therapy.

Third-line rescue therapy with levofloxacin after two H. pylori treatment failures

AIM

Eradication therapy with proton pump inhibitor, clarithromycin and amoxicillin fails in a considerable number of cases. A rescue therapy still fails in more than 20% of the cases. Our aim was to evaluate the efficacy and tolerability of a third-line levofloxacin-based regimen in patients with two consecutive Helicobacter pylori eradication failures.

DESIGN

Prospective multicenter study.

PATIENTS

In whom a first treatment with omeprazole-clarithromycin-amoxicillin and a second with omeprazole-bismuth-tetracycline-metronidazole (or ranitidine bismuth citrate with these antibiotics) had failed.

INTERVENTION

A third eradication regimen with levofloxacin (500 mg b.i.d.), amoxicillin (1 g b.i.d.), and omeprazole (20 mg b.i.d.) was prescribed for 10 days.

OUTCOME

Eradication was confirmed with 13C-urea breath test 4-8 wk after therapy.

RESULTS

One-hundred patients were initially included, and nine were lost for follow-up. All patients but five took all the medications correctly. Per-protocol and intention-to-treat eradication rates were 66% (95% CI = 56-75%) and 60% (50-70%). Adverse effects were reported in 25% of the patients, mainly including metallic taste (8%), nausea (8%), myalgia/arthralgia (5%), and diarrhea (4%); none of them were severe.

CONCLUSION

Levofloxacin-based rescue therapy constitutes an encouraging empirical third-line strategy after multiple previous H. pylori eradication failures with key antibiotics such as amoxicillin, clarithromycin, metronidazole, and tetracycline.

Helicobacter pylori first-line treatment and rescue options in patients allergic to penicillin

BACKGROUND

Helicobacter pylori eradication is a challenge in patients allergic to penicillin, especially those who have failed a first-eradication trial.

AIM

To assess the efficacy and tolerability of H. pylori first-line treatment and rescue options in patients allergic to penicillin.

METHODS

Prospective single centre study including 40 consecutive treatments administered to patients allergic to penicillin. Therapy regimens: First-line (12 patients) omeprazole, clarithromycin and metronidazole for 7 days; second-line (17 patients) ranitidine bismuth citrate, tetracycline and metronidazole for 7 days; third-line (nine patients) rifabutin, clarithromycin and omeprazole for 10 days; and fourth-line (two patients) levofloxacin, clarithromycin and omeprazole for 10 days.

OUTCOME VARIABLE

a negative (13)C-urea breath test 8 weeks after completion of treatment.

RESULTS

Per-protocol/intention-to-treat eradication rates were: first-line (64/58%); second-line (ranitidine bismuth citrate; 53/47%); third-line (rifabutin; 17/11%) and fourth-line regimen (levofloxacin; 100/100%). Compliance with treatment was generally good, except with the rifabutin-based regimen, which presented adverse effects in 89% of the patients, including four cases of myelotoxicity.

CONCLUSIONS

H. pylori-infected patients who are allergic to penicillin may be treated with a first-line treatment combining a proton-pump inhibitor, clarithromycin and metronidazole. Rescue options may include a regimen with ranitidine bismuth citrate, tetracycline and metronidazole. A levofloxacin-based rescue regimen (with proton-pump inhibitor and clarithromycin) may also represent an alternative, even when two or more consecutive eradication treatments have previously failed. However, rifabutin + clarithromycin + proton-pump inhibitor regimen is ineffective and poorly tolerated.

Helicobacter pylori "rescue" therapy after failure of two eradication treatments

Nowadays, apart from having to know well first-line eradication regimens, we must also be prepared to face Helicobacter pylori treatment failures. Therefore, in designing a treatment strategy we should not focus on the results of primary therapy alone, but also on the final--overall--eradication rate. After failure of a combination of proton pump inhibitor (PPI), amoxicillin, and clarithromycin, the use of empirical quadruple therapy (PPI-bismuth-tetracycline-metronidazole), has been generally used as the optimal second-line therapy. Even after two consecutive failures, several studies have demonstrated that H. pylori eradication can finally be achieved in almost all patients if several "rescue" therapies are consecutively given. It seems that performing culture even after a second eradication failure may not be necessary, as it is possible to construct an overall strategy to maximize H. pylori eradication, based on the different possibilities of empirical treatment (when antibiotic susceptibilities are unknown). Thus, if one does not want to perform culture before the administration of the third treatment after failure of the first two, different empirical treatments exist, including regimens based on: 1, amoxicillin (amoxicillin-PPI at high doses); 2, amoxicillin plus tetracycline (PPI-bismuth-tetracycline-amoxicillin, or ranitidine-bismuth-citrate-tetracyline-amoxicillin); 3, rifabutin (rifabutin-amoxicillin-PPI); 4, levofloxacin (levofloxacin-amoxicillin-PPI); and 5, furazolidone (furazolidone-bismuth-tetracycline-PPI).

Seven versus ten days of rabeprazole triple therapy for Helicobacter pylori eradication: a multicenter randomized trial

BACKGROUND

Ten-day triple therapy is somewhat more effective than 7-day treatment for curing Helicobacter pylori infection. Recent studies have suggested that rabeprazole-a proton pump inhibitor with fast onset of acid inhibition-could raise the efficacy of 7-day therapies to the levels obtained with 10-day treatment.

OBJECTIVE

To compare the efficacy of 7- and 10-day rabeprazole-based triple therapy for H. pylori eradication.

PATIENTS AND METHODS

Four hundred and fifty-eight patients were randomized to 7 or 10 days of triple therapy, including rabeprazole 20 mg, clarithromycin 500 mg, and amoxicillin 1 g, all twice a day. Cure rates were evaluated by urea breath test.

RESULTS

Two hundred and thirty-seven patients received 7-day and 221 received 10-day therapy. Groups were comparable in terms of demographic variables. Intention to treat cure rates were 73.8% (95% CI: 67-79%) for 7-day and 79.6% (95%: CI:74-85%) for 10-day therapy (p= 0.09). Per-protocol cure rates were 81.8% (95% CI:76-86%) and 89.3% (95% CI: 84-93%), p= 0.02, respectively. Cure rates were similar in peptic ulcer patients but in subjects without ulcer they were clearly lower for 7-day therapy: 66%versus 77% by intention to treat (p= 0.08) and 73%versus 91% in the per-protocol analysis (p= 0.004). Side effects and compliance in the two groups were comparable.

CONCLUSIONS

Seven- and 10-day triple therapies seem equally efficient in peptic ulcer patients. In contrast, 7-day therapy is significantly less effective in nonulcer dyspepsia patients. Ten-day therapy, therefore, seems preferable when treating nonulcer patients.

Eradication of Helicobacter pylori: recent advances in treatment

Helicobacter pylori plays a key role in dyspepsia, peptic ulcer disease, and gastric neoplasia and eradication of the infection has become an important treatment goal in clinical practice. Seven-day proton-pump inhibitor-amoxicillin-clarithromycin triple therapy is the current first-line therapy for H. pylori but eradication rates are compromised by poor compliance and antibiotic resistance. Ten-day sequential treatment may emerge as an alternative first-line therapy. Bismuth-based quadruple therapy is the second-line regimen of choice. Antimicrobial sensitivity testing is not recommended in the routine management of H. pylori infection. Novel triple-therapy regimens containing rifabutin, levofloxacin, or furazolidone may be useful alternatives as second- or third-line therapy.

Effectiveness of antiinfectives

BACKGROUND

Helicobacter pylori is one of the most common infections of mankind, with persistent colonization causing significant morbidity and mortality.

TREATMENT

First-line therapy, consisting of 7-day treatment with a proton pump inhibitor or ranitidine bismuth citrate, amoxicillin and clarithromycin, with second-line therapy, consisting of a proton pump inhibitor, bismuth, metronidazole, and tetracycline, in the case of failure, is chosen as the most cost-effective method of H. pylori eradication.

CONCLUSION

The effectiveness of these antiinfectives is limited by lack of compliance with treatment regimens, and increasing antibiotic resistance.

Rifaximin, a poorly absorbed antibiotic: pharmacology and clinical potential

Rifaximin (4-deoxy-4'-methylpyrido[1',2'-1,2]imidazo- [5,4-c]-rifamycin SV) is a synthetic antibiotic designed to modify the parent compound, rifamycin, in order to achieve low gastrointestinal (GI) absorption while retaining good antibacterial activity. Both experimental and clinical pharmacology clearly show that this compound is a nonsystemic antibiotic with a broad spectrum of antibacterial action covering Gram-positive and Gram-negative organisms, both aerobes and anaerobes. Being virtually nonabsorbed, its bioavailability within the GI tract is rather high with intraluminal and fecal drug concentrations that largely exceed the minimal inhibitory concentration values observed in vitro against a wide range of pathogenic organisms. The GI tract represents, therefore, the primary therapeutic target and GI infections the main indication. The appreciation of the pathogenic role of gut bacteria in several organic and functional GI diseases has increasingly broadened its clinical use, which is now extended to hepatic encephalopathy, small intestine bacterial overgrowth, inflammatory bowel disease and colonic diverticular disease. Potential indications include the irritable bowel syndrome and chronic constipation, Clostridium difficile infection and bowel preparation before colorectal surgery. Because of its antibacterial activity against the microorganism and the lack of strains with primary resistance, some preliminary studies have explored the rifaximin potential for Helicobacter pylori eradication. Oral administration of this drug, by getting rid of enteric bacteria, could also be employed to achieve selective bowel decontamination in acute pancreatitis, liver cirrhosis (thus preventing spontaneous bacterial peritonitis) and nonsteroidal anti-inflammatory drug (NSAID) use (lessening in that way NSAID enteropathy). This antibiotic has, therefore, little value outside the enteric area and this will minimize both antimicrobial resistance and systemic adverse events. Indeed, the drug proved to be safe in all patient populations, including young children. Although rifaximin has stood the test of time, it still attracts the attention of both basic scientists and clinicians. As a matter of fact, with the advancement of the knowledge on microbial-gut interactions in health and disease novel indications and new drug regimens are being explored. Besides widening the clinical use, the research on rifaximin is also focused on the synthesis of new derivatives and on the development of original formulations designed to expand the spectrum of its clinical use.

Efficacy and tolerability of rifampicin-based rescue therapy for Helicobacter pylori eradication failure in peptic ulcer disease

In vitro activity of rifampicin has been shown against H. pylori. It has also been reported that the prevalence of H. pylori is low in patients with tuberculosis treated with rifampicin. Clinical trials are required to establish the efficacy of rifampicin as a salvage therapy for eradication of H. pylori. We aimed to evaluate the efficacy of rifampicin-based salvage therapy for eradication of H. pylori in patients with peptic ulcer disease. Twenty-eight patients with peptic ulcer disease who either had failed eradication of H. pylori or had a recurrence of H. pylori following successful eradication were included in the prospective study. The inclusion criteria included one or more failed attempts at eradication and presence of H. pylori infection as evidenced by positivity of at least two of three tests: rapid urease test (RUT), 14C urea breath test (UBT), and histology. The subjects were treated with a 10-day regimen consisting of rifampicin, 450 mg od, tetracycline, 1 g bd, and esomeprazole, 40 mg bd. Four weeks after completion of therapy, H. pylori status was assessed by RUT, 14C, UBT, and histology. Liver function tests were done before and at the end of therapy. The study subjects included 25 males and 3 females with a mean age of 33.7+/-8.92 years (range: 22-65 years). The median duration of symptoms was 42 months, with a range of 1-180 months. The median number of eradication attempts was two, with one prior attempt in 6 (21.4%), two attempts in 19 (67.9%), and three attempts in 3 (10.7%) patients. Successful H. pylori eradication as defined by concomitant negativity of RUT, UBT, and histology with special stains was achieved in 32.1% (9/28) of patients by intention-to-treat and 33.3% (9/27) of patients by per-protocol analysis. This pilot study suggests that rifampicin-based regimes have no role as salvage eradication therapy in refractory cases of H. pylori infection with peptic ulcer disease.

Update on Therapeutic Options for Helicobacter pylori-related Diseases

Triple therapy including clarithromycin, amoxicillin, and a proton pump inhibitor (PPI) has been recommended as the treatment of choice for Helicobacter pylori eradication. This regimen is now challenged by an increasing level of clarithromycin resistance that jeopardizes the treatment success. When clarithromycin resistance has been detected, or when its rate is known to be high in the geographic area, this drug cannot be used. It can be replaced by metronidazole, the resistance of which has a limited clinical relevance. Another option is to prescribe tetracycline and metronidazole with a PPI or ranitidine bismuth citrate. New antibiotics such as levofloxacin or rifabutin can also be used in combination with amoxicillin and a PPI. Probiotics can be added to all of these regimens to improve compliance by decreasing adverse events. But some authors advocate a quadruple therapy as a first-line treatment. Solutions to improve the limitations of this last regimen are now being proposed. Clarification of the controversial treatment indications such as gastroesophageal reflux disease or prevention of nonsteroidal anti-inflammatory drug gastroduodenal symptoms has been made. The question of prevention of gastric carcinoma by H. pylori eradication remains unanswered.

New once-daily, highly effective rescue triple therapy after multiple Helicobacter pylori treatment failures: a pilot study

BACKGROUND

Helicobacter pylori treatment failure is a growing problem in daily practice.

AIM

To determine the efficacy of the combination of rabeprazole, levofloxacin and furazolidone as a rescue therapy.

METHODS

Duodenal ulcer patients previously submitted, without success, to at least two H. pylori treatment regimens were included. Gastroscopy (urease test, histological examination and culture) and (13)C-urea breath test were performed. All patients received a combination of rabeprazole 20 mg, levofloxacin 500 mg and furazolidone 200 mg (two tablets) administered in a single dose in the morning for 10 days. Clinical examination and a new (13)C-urea breath test were performed 90 days after therapy.

RESULTS

Twelve patients (eight females and four males), mean age 43 (30-58) years were included. Two patients failed to complete the treatment because of nausea and vomiting. Ten patients completed the study and took all the medications as advised. Culture was obtained in six patients: 100 and 83% of the samples were sensitive to furazolidone and levofloxacin, respectively. Per-protocol and intention-to-treat eradication rates were 100 and 83% (P = 0.019).

CONCLUSIONS

the combination of rabeprazole, levofloxacin and furazolidone in a single daily dose for 10 days constitutes a highly-effective and low-cost alternative as a third-line therapy in patients infected with H. pylori.

Comparison of two management strategies for Helicobacter pylori treatment: clinical study and cost-effectiveness analysis

BACKGROUND

First-line proton pump inhibitor-based triple and quadruple therapies for Helicobacter pylori eradication present similar levels of efficacy. Cross-over treatment (quadruple following triple failure, and triple following quadruple failure) seems the most sensible approach to treatment failures, but the two strategies -'quadruple first' versus 'triple first'- have not been previously compared. The aims of our study were to assess the usefulness and the cost-effectiveness of the two treatment strategies.

MATERIAL AND METHODS

Forty-nine out of 344 patients included in a previous study comparing triple therapy - 7 days of omeprazole, amoxicillin and clarithromycin twice a day - with quadruple therapy - 7 days of omeprazole twice a day, plus tetracycline, metronidazole and bismuth subcitrate three times a day - failed initial treatment and were assigned to cross-over therapy. Cure was determined by urea breath test. A decision analysis was performed to compare the two eradication strategies.

RESULTS

Intention to treat cure rates were 46% (10/22 patients; 95% CI 24-68%) for second-line triple therapy and 63% (17/27 patients; 95% CI 42-81%) for second-line quadruple therapy. Per protocol cure rates were 71% and 85%, respectively. Intention to treat cure rates were 87% (95% CI 81-92%) for the 'triple first' versus 86% (95% CI 80-91%) for the 'quadruple first' strategy (p = .87). The 'quadruple first' strategy was more cost-effective. The incremental cost of 'triple first' strategy per person was 19 in the low-cost area and 65 US dollars in the high-cost area.

CONCLUSIONS

The effectiveness of 'triple first' and 'quadruple first' strategies is similar, although the latter seems slightly more cost-effective.

Rifabutin based triple therapy for eradication of H. pylori primary and secondary resistant to tinidazole and clarithromycin

BACKGROUND

Rifabutin has been empirically used in Helicobacter pylori infections resistant to triple therapy. There are no data on primary and secondary resistance to rifabutin and its use in specific cases.

AIM

To analyse the susceptibility and resistance to rifabutin in H. pylori-positive patients with or without previous H. pylori therapy and to test the efficacy of rifabutin in H. pylori resistant to clarithromycin and tinidazole.

METHODS

Four hundred and twenty H. pylori-positive patients without previous exposure to triple therapy and 104 patients who had already received one course of triple therapy underwent upper endoscopy for dyspeptic symptoms and H. pylori susceptibility test. Amoxicillin, clarithromycin, tinidazole and rifabutin were evaluated for resistance and susceptibility. Forty patients with primary resistance to both clarithromycin and tinidazole and with susceptibility to amoxicillin and rifabutin, and 65 patients with secondary resistance and susceptibility to the same antibiotics were identified. All these patients received a 10-day triple therapy with pantoprazole amoxicillin and rifabutin. Treatment success was evaluated by the 13C-Urea Breath test.

RESULTS

In naive patients 23% of strains were resistant to clarythromycin, 35% to tinidazole, 9% to both antibiotics, and none was resistant to rifabutin In patients already treated the percentages of resistant strains were 76, 64.4, 62.5 and 1%, respectively. With rifabutin based triple therapy eradication rates were (Per Protocol and Intention-to-Treat analysis) 100 and 87.5% in primary resistance to clarithromycin and tinidazole and 82.2 and 78.5% in secondary resistance.

CONCLUSION

H. pylori primary and secondary resistances to clarithromycin and tinidazole are high in our geographic area, while resistance to rifabutin is rare. Rifabutin-based triple therapy, can be successfully used in primary and secondary resistance to clarithromycin and tinidazole according to the in vitro susceptibility test.

Rifabutin- and furazolidone-based Helicobacter pylori eradication therapies after failure of standard first- and second-line eradication attempts in dyspepsia patients

BACKGROUND

Optimal management approach is not well defined for subjects who fail initial first- and second-line Helicobacter pylori eradication attempts and are dealt on a case-by-case basis by the specialists.

AIM

To evaluate the efficacy and safety of standard and 'rescue' eradication therapies at primary and secondary care levels.

METHODS

H. pylori infected dyspepsia patients referred to our C13 urea breath testing laboratory between January 1999 to February 2002 were included. Eradication failure at secondary care level was treated using strategies including antibiotic sensitivity testing and the use of rifabutin- and furazolidone-based therapies.

RESULTS

3280 patients received standard first-line eradication therapy, which was successful in 2530 (77%) patients. Second-line therapy (bismuth-based 'quadruple') or triple therapy (altering constituent antibiotics) was successful in 56% of 270 treated patients. Subsequent eradication attempts using rifabutin-based (n = 34) and furazolidone-based (n = 10) regimens were successful in 38% and 60% patients respectively. H. pylori eradication rates were significantly different for guidelines compliant (94.8%) and non-compliant (82%) groups (P = 0.0001). H. pylori eradication rates for non-ulcer dyspepsia (40%) and peptic ulcer disease (36%) were not significantly different.

CONCLUSIONS

Available H. pylori eradication therapies remain very effective and compliance to guidelines achieves high success rates. Furazolidone-based 'rescue' regimen achieved high eradication rates after failure of the standard first-line, second-line and rifabutin-based therapies.

Basis for the management of drug-resistant Helicobacter pylori infection

The discovery that most stomach diseases are a consequence of an Helicobacter pylori infection has completely changed the management of stomach diseases. Antibacterials are the treatment of choice in addition to proton pump inhibitors (PPIs) or ranitidine bismuth. We are now faced with the problem of antimicrobial resistance, which is the main cause of treatment failure. H. pylori acquires resistance essentially via point mutations, and today this phenomenon is found with most antibacterials. The most important resistance to consider is that to clarithromycin, since it is the first-choice antibacterial and clarithromycin resistance is highly clinically significant. Quadruple therapy or triple therapies with amoxicillin-metronidazole or tetracycline-metronidazole and a PPI or ranitidine bismuth can then be used despite a possible resistance to metronidazole if the strain is resistant to clarithromycin. Resistance to both clarithromycin and metronidazole may lead to the use of other combinations, i.e. amoxicillin-rifabutin, amoxicillin-levofloxacin or amoxicillin-furazolidone. Resistance to any of these drugs means their use must be avoided. In some instances, it may also be advisable to prescribe amoxicillin as the sole antibacterial, or to use a quadruple therapy with furazolidone instead of metronidazole. Although it is theoretically possible to cure a drug-resistant H. pylori infection, a practical limitation is the availability of the drugs in certain countries. Furthermore, the progressive increase in drug resistance warrants the need for new antibacterials in the near future.

[Evaluation of Helicobacter pylori susceptibility to rifaximin]

INTRODUCTION

Helicobacter pylori infection affects more than half the world's population. It is a major cause of chronic gastritis and there is a strong association with peptic ulceration and gastric adenocarcinoma. Rifaximin is a new nonabsorbable broad-spectrum antimicrobial agent that reaches high concentrations in the gastrointestinal tract.

AIM

To evaluate the in vitro activity of rifaximin against H. pylori isolates.

METHODS

Thirty-one H. pylori strains were analyzed by the agar dilution method. Clarithromycin was used as the control antibiotic. Staphylococcus aureus and Streptococcus pneumoniae were used as quality control strains. Plates were read at days 4 and 7 of incubation. The MIC50 and MIC90 of each antibiotic were calculated. Strains with a clarithromycin MIC of > 1 microg/ml were considered resistant.

RESULTS

The MIC50 of clarithromycin at days 4 and 7 was 0.125 microg/ml and the MIC90 at days 4 and 7 ranged from 8 to 16 microg/ml, respectively. The MIC50 of rifaximin at days 4 and 7 ranged from 1 to 2 microg/ml, respectively, and the MIC90 was 4 microg/ml at both days 4 and 7. Twenty percent of H. pylori strains were resistant to clarithromycin. All clarithromycin-resistant strains were inhibited at a maximal rifaximin concentration of 4 microg/ml.

CONCLUSION

These results indicate that this new antibiotic may be useful for eradication of H. pylori infection. Because rifaximin is active against H. pylori strains resistant to clarithromycin, it could be useful in combination with this drug or in the treatment of therapeutic failure.

Therapy of Helicobacter pylori

This represents an overview of the main data published over the last year on the therapy of Helicobacter pylori. The problem of increasing failure of H. pylori eradication has been the main focus, with increasing resistance and poor patient compliance being the main culprits. Simple regimens are necessary to improve patient compliance. New antibiotics and novel agents are appraised with mixed results.

[Eradication and chronic acid suppression. Advances and pseudo-advances]

Guidelines for Helicobacter pylori therapy were proposed at the Maastricht 2/2000 conference. Since then no further major developments have been made. An evidenced based choice of treatment is thereby nearly impossible as large randomized trials have not been performed. Minor progress could be achieved in the areas of second-line and rescue treatment options after failure of the standard therapy. At present proton pump inhibitors are the most powerful drugs for the treatment of gastro-oesophageal reflux disease. No additional progress has been achieved concerning therapy of reflux disease in the last years. Reasonable anxiety about the safety of long-term acid suppression with proton pump inhibitors diminished over years as no significant increase in cancer development could be detected.

High efficacy of 1-week doxycycline- and amoxicillin-based quadruple regimen in a culture-guided, third-line treatment approach for Helicobacter pylori infection

BACKGROUND

Helicobacter pylori infection may persist after both first- and second-line current treatments.

AIM

To assess the efficacy of a third-line, culture-guided treatment approach for the eradication of H. pylori.

METHODS

Patterns of resistance were analysed in H. pylori isolates from 94 consecutive patients in whom H. pylori infection had persisted after two eradication attempts. Using the epsilometer test, susceptibility analysis was performed for amoxicillin, clarithromycin, metronidazole, tetracycline and levofloxacin. Patients were then treated with a culture-guided, third-line regimen: 89 patients with a 1-week quadruple regimen including omeprazole, bismuth, doxycycline and amoxicillin, and five patients with a 1-week triple regimen containing omeprazole, amoxicillin and levofloxacin or clarithromycin.

RESULTS

Ninety-four subjects (100%) were resistant to metronidazole, 89 (95%) to clarithromycin, 29 (31%) to levofloxacin and five (5%) to tetracycline. No resistance to amoxicillin was found in any patient. Overall, H. pylori eradication was obtained in 90% of subjects. The quadruple regimen was effective in 81 patients (92% by per protocol and 91% by intention-to-treat analysis). Four patients (80%, both per protocol and intention-to-treat analysis) were H. pylori-negative after the triple regimen.

CONCLUSIONS

A culture-guided, third-line therapeutic approach is effective for the eradication of H. pylori. Furthermore, the 1-week doxycycline- and amoxicillin-based quadruple regimen is a good third-line 'rescue' treatment option.

Randomized study of different 'second-line' therapies for Helicobacter pylori infection after failure of the standard 'Maastricht triple therapy'

BACKGROUND

Triple therapy with proton pump inhibitor, clarithromycin and amoxicillin and, in the event of eradication failure, quadruple therapy with proton pump inhibitor, bismuth, tetracycline and metronidazole have been proposed in Maastricht as the optimal sequential treatment of Helicobacter pylori infection.

AIM

To compare two second-line regimens with quadruple therapy.

METHODS

One hundred and eighty patients with a previous failed course of standard therapy were randomly given one of the following 7-day treatments: ranitidine bismuth citrate 400 mg b.d. plus amoxicillin 1 g b.d. and tinidazole 500 mg b.d. (RBCAT), pantoprazole 40 mg b.d. plus amoxicillin 1 g b.d. and levofloxacin 500 mg/day (PAL) and pantoprazole 40 mg b.d., bismuth citrate 240 mg b.d., tetracycline 500 mg q.d.s. and metronidazole 500 mg b.d. (PBTM). The eradication rate was assessed by 13C-urea breath test. Side-effects and compliance were evaluated by a standardized questionnaire and by counting returned medication.

RESULTS

The RBCAT, PAL and PBTM groups achieved mean intention-to-treat eradication rates of 85%, 63% and 83%, respectively (P<0.05 for PAL vs. either RBCAT or PBTM). Compliance was optimal in all patients, although side-effects were more commonly observed in the PBTM group than in the other two patient groups (P<0.0001).

CONCLUSIONS

Both RBCAT and PBTM can be used as second-line therapies. Conversely, PAL did not achieve satisfactory eradication rates.

Treatment of Helicobacter pylori infection

Review of the recently published data on Helicobacter pylori management highlights various interesting aspects. Current H. pylori eradication guidelines generally suggest a noninvasive 'test and treat' strategy for all dyspeptic patients with certain age limits depending on the local gastric neoplasia risk. According to the 'Maastricht 2-2000 Consensus Report' treatment should be thought of as a 'package' considering first- and second-line eradication therapies together. Various centres have published their results using novel antimicrobial formulations and 'rescue' and 'sequential' therapies. Review suggests that care at the specialist level remains a challenge and guidelines are deficient particularly as regards the selection and duration of eradication therapies. Results indicate that differences for CYP2C19 genotype and the selection of proton pump inhibitors have no significant role in determining eradication rates whereas antibiotic resistance and socio-economic factors play a variable role according to different geographical areas. Compliance remains an important factor in determining clinical outcome at the primary and secondary levels worldwide.

Quadruple therapy containing amoxicillin and tetracycline is an effective regimen to rescue failed triple therapy by overcoming the antimicrobial resistance of Helicobacter pylori

AIM

To identify optimal antibiotics for second-line quadruple therapy of Helicobacter pylori after failed 1-week triple therapy.

METHODS

One hundred patients were enrolled in this study after the failure of 1-week triple therapy. They were randomized to receive 1-week quadruple therapy consisting of amoxicillin, omeprazole and bismuth salts, plus either metronidazole or tetracycline. Before quadruple therapy, the H. pylori culture of each patient was tested for metronidazole resistance or clarithromycin resistance by E-test. Six weeks later, an endoscopy or 13C-urea breath test was used to define the success of H. pylori eradication.

RESULTS

The H. pylori eradication rates by intention-to-treat and per protocol analysis were higher in the tetracycline group than in the metronidazole group (intention-to-treat: 78% vs. 58%, P < 0.05; per protocol: 89% vs. 67%, P < 0.05). In the metronidazole group, but not in the tetracycline group, the per protocol eradication rate of quadruple therapy was lower for the infected isolates with metronidazole resistance than for those without metronidazole resistance (77% vs. 33%, P < 0.05).

CONCLUSION

Quadruple therapy, including tetracycline and amoxicillin, improves the H. pylori eradication rate after failed triple therapy.

Triple vs. quadruple therapy for treating Helicobacter pylori infection: a meta-analysis

BACKGROUND

Triple therapy (proton pump inhibitor, clarithromycin and amoxicillin or an imidazole) is the first-line treatment for Helicobacter pylori infection. However, the effectiveness of triple therapy is decreasing due to the increase in antibiotic resistance. Quadruple therapy (proton pump inhibitor, tetracycline, metronidazole and a bismuth salt) is a very effective regimen even in areas of high prevalence of antibiotic resistance, and may be an alternative first-line treatment.

AIM

To compare triple vs. quadruple therapy for the first-line treatment of H. pylori infection.

METHODS

An extensive literature search was performed to identify randomized trials comparing triple vs. quadruple therapy. Selected trials were included in a meta-analysis using Review Manager 4.1.

RESULTS

Four studies met the inclusion criteria. Eradication rates with quadruple therapy were slightly higher in both the intention-to-treat (81% vs. 78%; odds ratio, 0.83; 95% confidence interval, 0.61-1.14) and per protocol (88% vs. 85%; odds ratio, 0.81; 95% confidence interval, 0.55-1.20) analysis, although the differences were not statistically significant. Nor were there significant differences in compliance or adverse effects between the therapies.

CONCLUSION

Triple and quadruple therapies seem to be roughly equivalent in terms of effectiveness, compliance and side-effects profile when administered as first-line treatment for H. pylori infection.