The sequential therapy regimen forHelicobacter pylorieradication

Recognition of Helicobacter pylori by protein-targeting aptamers

BACKGROUND

Helicobacter pylori (H pylori) is a disease-causing pathogen capable of surviving under acidic conditions of the human stomach. Almost half of the world's population is infected with H pylori, with gastric cancer being the most unsatisfactory prognosis. Although H pylori has been discovered 30 years ago, the effective treatment and elimination of H pylori continue to be problematic.

MATERIALS AND METHODS

In our study, we screened nucleic acid aptamers using H pylori surface recombinant antigens as targets. Trypsin was used for separating aptamers that were bound to proteins. Following nine rounds of screening, we performed sequence similarity analyses to assess whether the aptamers can recognize the target protein. Two sequences with desirable recognition ability were selected for affinity detection. Aptamer Hp4 with the strongest binding ability to the H pylori surface recombinant antigen was chosen. After optimization of the binding conditions, we conducted specificity tests for Hp4 using Escherichia coli, Staphylococcus aureus, Vibrioanguillarum, and H pylori.

RESULTS

The data indicated that the aptamer Hp4 had an equilibrium dissociation constant (K_d ) of 26.48 ± 5.72 nmol/L to the target protein. This aptamer was capable of exclusively detecting H pylori cells, without displaying any specificity for other bacteria.

CONCLUSIONS

We obtained a high-affinity aptamer for H pylori, which is expected to serve as a new molecular probe for detection of H pylori.

Hybrid Therapy Regimen for Helicobacter Pylori Eradication

Objective:

Helicobacter pylori (H. pylori) eradication remains a challenge with increasing antibiotic resistance. Hybrid therapy has attracted widespread attention because of initial report with good efficacy and safety. However, many issues on hybrid therapy are still unclear such as the eradication efficacy, safety, compliance, influencing factors, correlation with antibiotic resistance, and comparison with other regimens. Therefore, a comprehensive review on the evidence of hybrid therapy for H. pylori infection was conducted.

Data Sources:

The data used in this review were mainly from PubMed articles published in English up to September 30, 2015, searching by the terms of “Helicobacter pylori” or “H. pylori”, and “hybrid”.

Study Selection:

Clinical research articles were selected mainly according to their level of relevance to this topic.

Results:

Totally, 1871 patients of 12 studies received hybrid therapy. The eradication rates were 77.6–97.4% in intention-to-treat and 82.6–99.1% in per-protocol analyses. Compliance was 93.3–100.0%, overall adverse effects rate was 14.5–67.5%, and discontinued medication rate due to adverse effects was 0–6.7%. H. pylori culture and sensitivity test were performed only in 13.3% patients. Pooled analysis showed that the eradication rates with dual clarithromycin and metronidazole susceptible, isolated metronidazole or clarithromycin resistance, and dual clarithromycin and metronidazole resistance were 98.5%, 97.6%, 92.9%, and 80.0%, respectively. Overall, the efficacy, compliance, and safety of hybrid therapy were similar with sequential or concomitant therapy. However, hybrid therapy might be superior to sequential therapy in Asians.

Conclusions:

Hybrid therapy showed wide differences in the efficacy but consistently good compliance and safety across different regions. Dual clarithromycin and metronidazole resistance were the key factor to efficacy. Hybrid therapy was similar to sequential or concomitant therapy in the efficacy, safety, and compliance.

Sequential Therapy vs Quadruple Therapy for Helicobacter pylori Eradication in South West of Iran

Aim

To compare the efficacy of quadruple and sequential therapy in eradication of Helicobocter pylori (H. pylori) in a randomized study.

Method

Three hundred H. pylori positive patients were enrolled into the study. These patients were randomly divided into two groups: group I (n = 150) received quadruple therapy (20 mg omeprazole bid, 240 mg bismuth subcitrate bid, 1,000 mg tetracycline bid and 500 mg metronidazole bid) for 14 days, group II (n = 150) received sequential therapy (20 mg omeprazole bid, 1,000 mg amoxicillin bid for 5 days, followed by 20 mg omeprazole bid, 500 mg metronidazole bid, 500 mg clarithromycin for the other 5 days). H. pylori status was assessed by histology and rapid urease test at baseline. Follow-up breath test by 14C urea breath test (UBT) was performed 4 weeks after completion of treatment. Eradication was defined as negative results on UBT.

Results

Successful eradication was achieved in 245 patients. In each group, five patients did not tolerate the regimen and were excluded from analysis. About 29 (20%) patients who received sequential therapy and 21 (14.5%) of the quadruple group tolerated mild side effects (p = 0.21).

Per-protocol analysis demonstrated eradication rates of 86.9% for sequential therapy and 82.7% for quadruple therapy (p = 0.26). Results according to the intention to treat analysis were 84 and 79.5% in the sequential and quadruple group respectively. Eradication rate differences were not significant.

Conclusion

The success rate of sequential therapy is comparable with quadruple therapy. Sequential therapy due to the short duration and lesser drug usage is a good alternative for eradication of H. pylori in the country.

How to cite this article: Masjedizadeh AR, Hajiani E, Hashemi SJ, Alavinejad P, Dalvand H. Sequential Therapy vi Quadruple Therapy for Helicobocter pylori Eradication in South West of Iran. Euroasian J Hepato-Gastroenterol 2014;4(2):63-66.

Therapy of Helicobacter pylori: present medley and future prospective

The increasing prevalence of antimicrobial resistance has warned clinicians to adopt new strategies for dealing with the H. pylori infection. The success of various therapeutic regimens has recently declined to unacceptable levels. To date, first line therapies (including concomitant therapy and hybrid therapy), second line therapies (including bismuth-containing quadruple therapy and levofloxacin-containing therapy), and third line therapy (culture-guided therapy) had been introduced. In the near future, treatment of H. pylori is entering into a completely new resistance era. In this setting, despite the recent progress, we may only be targeting the patients with problematic H. pylori. Local preference for antibiotic selection should be an inevitable article in each therapeutic regimen worldwide. Meanwhile, improving the patients' compliance protocols and observed side effects in suggested therapeutic regimens should be considered cautiously. The new strategies in treatment should be adopted based upon local resistance patterns, which requires physician's resistance about the recommended guidelines. Designing new therapeutic regimen, which contains most effective available antibiotics with less possible side effects and high patient compliance, represents a challenging task in treatment of H. pylori infections.

Current pharmacotherapy options for gastritis

INTRODUCTION

Gastritis is a broad term, which is used for different conditions by clinicians, endoscopists and pathologists. Classification strategies have led to more congruence between specialists. The histological evaluation of the gastric mucosa is mandatory for diagnosing and classifying gastritis. Main aetiologic factor is infection with Helicobacter pylori. The clinical importance of gastritis lays in the fact that it predisposes to more pronounced damage to the gastric mucosa, in particular peptic ulcer disease, and eventually atrophic gastritis, intestinal metaplasia and gastric malignancy, both adenocarcinoma and MALT lymphoma.

AREAS COVERED

This review covers the current pharmacotherapy options for different forms of gastritis. The main focus is on H. pylori-induced gastritis. Thereafter, other forms of gastritis like autoimmune gastritis and non-steroidal anti-inflammatory drug (NSAID)-related gastropathy are covered.

EXPERT OPINION

The emerging problem of antibiotic resistance requires an accurate knowledge of local eradication rates. Standard triple therapy should be abandoned in regions with high clarithromycin resistance. In these areas, sequential or quadruple therapy is best initial treatment. Further research should focus on non-invasive and effective techniques of susceptibility testing, making a tailored and cost-effective approach. Primary prevention of NSAID-related gastropathy can be enhanced by better education for clinicians and patients, so that both right prescription of gastroprotective agents as therapy adherence will improve.

Comparison of sequential and standard therapy for Helicobacter pylori eradication in children and investigation of clarithromycin resistance

AIMS

The aim of the present study was to compare the efficacy of sequential and standard triple-drug regimen for Helicobacter pylori (H pylori) eradication in children and to determine the primary resistance rate to clarithromycin.

METHODS

Children with H pylori infection randomized to receive either standard regimen (n = 28) consisting of lansoprazole for 30 days, amoxicillin and clarithromycin for 14 days or sequential regimen (n = 16) consisting of lansoprazole for 30 days, amoxicillin for 7 days, followed by clarithromycin and metronidazole for the next 7 days. Clarithromycin susceptibility of H pylori was assessed with fluorescence in-situ hybridization technique. Eradication was controlled by C urea breath test or monoclonal stool antigen test 4 weeks after the end of the therapy.

RESULTS

H pylori eradication rate was higher in the sequential therapy group (93.7%), compared with the standard therapy group (46.4%) (P = 0.002). There was no difference in adverse drug reactions and in compliance to the treatment between the groups. Primary clarithromycin resistance rate for H pylori was found as 25.7% (n = 9). All of the patients having clarithromycin resistance were coincidentally in the standard therapy group. After the exclusion of these 9 patients, sequential therapy was again found to be more effective than the standard therapy (P = 0.02).

CONCLUSIONS

Sequential therapy seems highly effective for eradicating H pylori in children; however, the difference between 2 groups in resistant strains was the limitation of the study. Our country needs to reassess the effectiveness of standard triple therapy regimen for H pylori eradication.

High-dose, ten-day esomeprazole, amoxicillin and metronidazole triple therapy achieves high Helicobacter pylori eradication rates

BACKGROUND

Strong acid inhibition using esomeprazole increases cure rates with triple therapy and 10-day treatments are more effective than 7-day ones. The combination of amoxicillin plus metronidazole at full doses, and using a physiologically-correct schedule three times a day, and has been shown to overcome metronidazole resistance and to achieve good eradication rates.

AIMS

To assess the eradication rate of a new first-line treatment regimen associating strong acid inhibition, amoxicillin and metronidazole and to evaluate tolerance.

METHODS

Patients from eight hospitals were included. Helicobacter pylori status was assessed by at least one of the following: histology, culture, rapid urease test or urea breath test (UBT). Ten-day treatment was prescribed comprising esomeprazole 40 mg twice a day plus amoxicillin 1 g and metronidazol 500 mg both three times a day. Helicobacter pylori cure was assessed by UBT.

RESULTS

A hundred and thirty-six patients were enrolled. Mean age was 52.6 ± 16 years and 59.6% of patients were men. Main indications for treatment were: uninvestigated dyspepsia (13.6%); functional dyspepsia (18.2%); gastric ulcer (21.8%); and duodenal ulcer (39.8%). Helicobacter pylori eradication was achieved in 112 of the 127 patients who returned for follow-up. Eradication rates were 82.4% (95% CI: 74.7-88.1) by intention-to-treat analysis and 88.2% (95% CI: 81.2-92.8) by per protocol. Treatment was well tolerated and no major side effects were reported. Nine patients complained of mild side effects.

CONCLUSIONS

Cure rates of the combination of esomeprazole, amoxicillin and metronidazole are high and the treatment was well tolerated. This pilot study warrants the comparison of this schedule with current standards.

Low efficacy of clarithromycin including sequential regimens for Helicobacter pylori infection

BACKGROUND

Sequential treatment for Helicobacter pylori (H. pylori) appears to achieve a better eradication rate than triple therapy. However, most of the data have been reported from the Italy, and studies from different population are needed before it is recommended in clinical practice. The present study aimed to assess and compare the efficacy of two separate clarithromycin including sequential regimens in Turkey which is well known with high clarithromycin and metronidazole resistance to H. pylori.

METHODS

Consecutive H. pylori -positive patients with non-ulcer dyspepsia were randomly allocated to one of the two sequential regimens; the first group was given lansoprazole 30 mg b.i.d. plus amoxicillin 1 g b.i.d. for the first week, followed by lansoprazole 30 mg b.i.d., clarithromycin 500 mg b.i.d., and metronidazole 500 mg t.i.d. for the second week (LA-CM). The second arm was given the same regimen but tetracycline500 g q.i.d. instead of metronidazole (LA-CT). H. pylori was detected with urea breath test (UBT) and histology before enrollment. UBT was repeated at 6th weeks after treatment.

RESULTS

A total of 200 patients were enrolled in groups and 179 of them completed their protocols. The cumulative per protocol ("PP") and intention-to-treat ("ITT") eradication rates were 74.3% and 66.5% in all patients, respectively. Both "PP" (78.2% vs 70.1%) and "ITT" (72% vs 61%) eradication rates were better in LA-CT group than LA-CM group, but the differences were not statistically significant (p > .05). Both regimens were well tolerated, and the incidence of adverse effects was comparable.

CONCLUSION

Two weeks clarithromycin including sequential regimens with metronidazole or tetracycline were not achieved acceptable eradication rates in Turkey.

New effective treatment regimen for children infected with a double-resistant Helicobacter pylori strain

BACKGROUND

The increasing number of pediatric patients infected with multiresistant Helicobacter pylori strains calls for evaluation of treatment regimens. Second-line antibiotics such as tetracycline or quinolones are not licensed for children. Because in vivo resistance to metronidazole may be overcome in vivo by a high dose and prolonged intake, we evaluated the eradication rate and side effects of a high-dose triple therapy in pediatric patients with culture-proven double resistance.

PATIENTS AND METHODS

In this open multicentre trial, 62 children (<18 years, body weight >15 kg) infected with an H pylori strain resistant to metronidazole and clarithromycin were treated according to body weight classes with amoxicillin (∼ 75 mg/kg/day), metronidazole (∼ 25 mg/kg/day) and esomeprazole (∼ 1.5 mg/kg/day) for 2 weeks. Adherence and adverse events were assessed by a 2-week diary and telephone interviews at days 7 and 14 of treatment. Primary outcome was a negative C-urea breath test after 6 weeks.

RESULTS

Of 62 patients, 5 were lost to follow-up, 12 were nonadherent, and 45 treated per protocol. Eradication rates were 66% (41/62) [confidence interval 54-78] (intention to treat) and 73% (33/45) [confidence interval 60-86] (per protocol). Success of treatment was not related to dose per kilogram body weight. Mild to moderate adverse events were reported by 21 patients, including nausea (10.8%), diarrhoea (8.9%), vomiting (7.1%), abdominal pain (5.4%), and headache (3.6%), and led to discontinuation in 1 child.

CONCLUSION

High-dose amoxicillin, metronidazole, and esomeprazole for 2 weeks is a good treatment option in children infected with a double resistant H pylori strain.

Double-blind randomized trial of quadruple sequential Helicobacter pylori eradication therapy in asymptomatic infected children in El Paso, Texas

OBJECTIVES

We assessed the efficacy of a novel quadruple sequential 10-day eradication therapy, its compliance, and reported adverse events in a sample of asymptomatically Helicobacter pylori-infected children in El Paso, Texas, as part of a study aiming to assess the influence of this infection on the levels of markers of iron stores.

PATIENTS AND METHODS

Using a double-blind randomized trial design, 110 asymptomatic children ages 3 to 11 with H pylori infection were randomly assigned to receive either a 10-day course of sequential eradication therapy plus 6 weeks of iron supplementation, eradication therapy plus placebo, iron supplementation plus placebo, or placebo only. H pylori infection status was assessed ≥45 days after treatment using the urea breath test. Analyses compared the proportion of subjects cured according to assignment to and completion of the sequential eradication therapy.

RESULTS

Intent-to-treat and per-protocol analyses indicated that 44.3% and 52.9%, respectively, of the children receiving the novel quadruple sequential therapy had their infection eradicated compared with 12.2% and 15.4% in the arms receiving iron or placebo only, respectively (P < 0.001 in both analyses). Study medications were taken with no or only mild adverse events in most children.

CONCLUSIONS

A quadruple sequential regimen eradicated H pylori in only half the asymptomatic children receiving this treatment. There was no difference in the cure rates of those receiving iron supplementation and those receiving placebo.

Identification of 3',4',5'-trimethoxychalcone analogues as potent inhibitors of Helicobacter pylori-induced inflammation in human gastric epithelial cells

Efforts to identify potent small molecule inhibitors of Helicobacter pylori led to the evaluation of 23 3',4',5'-trimethoxychalcone analogues. Some of the compounds displayed potent antibacterial activity against H. pylori. Three most active and selective compounds 1, 7, and 13 also showed the bactericide activity against the reference as well as multidrug-resistant strains of H. pylori. Additionally, the aforementioned three compounds potentially inhibited the H. pylori adhesion and invasion to human gastric epithelial (AGS) cells. Furthermore, these selective compounds inhibited the H. pylori-induced gastric inflammation by reduced inflammatory mediator's nuclear factor kappa B activation, and the secretion of interleukin-8.