Helicobacter Pylori Infection

53

Review clinical trials related to Helicobacter Pylori Infection. Use filters to narrow results by trial status, phase, treatment, biological sex and sponsor.

Condition / disease
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Status: Not yet recruiting

Vonoprazan-Amoxicillin Dual Therapy for Helicobacter Pylori Infection in United States Adolescents

Helicobacter pylori (H. pylori) is a common bacterial infection of the stomach that can cause chronic stomach inflammation, ulcers, and other digestive problems. The infection is more common among some racial and ethnic minority groups and people from lower-income households, contributing to ongoing health disparities. Current treatment for H. pylori usually requires multiple medications, including antibiotics and acid-suppressing drugs. However, increasing antibiotic resistance has made some standard treatments less effective and can lead to treatment failure. There is a need for simpler, effective treatment options that use fewer antibiotics while maintaining high cure rates. This study will evaluate a treatment consisting of two medications: vonoprazan, an acid-suppressing medication, and amoxicillin, an antibiotic. Vonoprazan provides strong and consistent acid suppression, which may improve the effectiveness of amoxicillin in eliminating H. pylori. Studies in adults and limited studies in children have shown promising results, but this treatment has not been well studied as an initial treatment for adolescents in the United States. The purpose of this study is to determine whether vonoprazan plus amoxicillin is a safe, effective, and practical first-line treatment for adolescents with H. pylori infection. Participants will receive the study treatment and undergo follow-up testing to determine whether the infection has been eradicated. The results may help inform future treatment recommendations and provide additional treatment options for children and adolescents with H. pylori infection.

Participants needed: 55
Trial details
Phase: Phase 2Age: 10-18Biological sex: AllType: InterventionalSponsor: Boston Children's HospitalUpdated: Oct 6, 2026
Eligibility criteria

Weight ≥35 kg. [+4]

Known allergy or hypersensitivity to penicillin or amoxicillin. [+3]

Status: Not yet recruiting

Factors Affecting Helicobacter Pylori Infection: Diet and Lifestyle Patterns

This cross-sectional observational study aims to determine the prevalence of Helicobacter pylori (H. pylori) infection among Information Technology (IT) professionals working in Hyderabad, India, and to identify dietary, lifestyle, occupational, and clinical factors associated with infection. H. pylori is a common bacterial infection of the stomach and is an important cause of chronic gastritis, peptic ulcer disease, and gastric cancer. Approximately 1,000 eligible IT professionals will be enrolled from participating IT companies using stratified random sampling. Participants will complete a structured questionnaire covering demographic characteristics, dietary habits, occupational factors, gastrointestinal symptoms, lifestyle factors, medical history, and recent medication use. Active H. pylori infection will be determined using the carbon-14 (C14) urea breath test performed at the workplace under standardized conditions. The study will estimate the prevalence of H. pylori infection in this occupational group and evaluate whether factors such as outside food consumption, office-delivered meals, restaurant dining, street food intake, work schedules, and lifestyle habits are associated with infection. The findings may help identify modifiable risk factors and contribute to the development of workplace health promotion and preventive strategies for IT professionals.

Participants needed: 1,000
Trial details
Age: 21-55Biological sex: AllType: ObservationalSponsor: Asian Institute of Gastroenterology, IndiaUpdated: Sep 23, 2026
Eligibility criteria

Age ≥21 years. [+5]

Previous Helicobacter pylori eradication treatment. [+9]

Status: Not yet recruiting

Bacillus Probiotics With Bismuth Quadruple Therapy for Helicobacter Pylori Infection

Helicobacter pylori (H. pylori) is a very common gastrointestinal disease that colonises the human gastric mucosa and is a primary risk factor for chronic gastritis, peptic ulcer disease, and gastric cancer. The standard first-line treatment for H. pylori eradication is bismuth-containing quadruple therapy. While effective, this aggressive, multi-antibiotic regimen frequently induces significant gastrointestinal adverse effects and severe disruption of the normal gut microbiota (dysbiosis). These side effects often lead to poor patient compliance, which in turn contributes to treatment failure and the increasing global challenge of antibiotic resistance. Emerging clinical evidence strongly supports the use of probiotics as an adjuvant therapy to alleviate antibiotic-associated side effects and significantly aid in restoring intestinal balance. Spore-forming Bacillus species, specifically Bacillus clausii, Bacillus subtilis, and Bacillus coagulans, are particularly advantageous due to their natural resistance to acidic gastric conditions and concurrent antibiotic administration, allowing them to remain viable and active during the intensive eradication therapy. This clinical trial is designed as a randomised, double-blind, placebo-controlled study to evaluate the clinical efficacy, adverse effects, and treatment adherence of a standard four-drug bismuth-containing regimen for the treatment of H. pylori infection when combined with single-strain and multi-strain Bacillus probiotics. The trial is conducted in the Gastroenterology Department of Tam Anh Hospital. 336 participants diagnosed with H. pylori infection and prescribed the standard 14-day bismuth-containing quadruple therapy are randomly divided and allocated to receive either a single-strain probiotic (LiveSpo Clausy), a multi-strain probiotic (LiveSpo DIA 30), or an identical placebo. Over 8 weeks of follow-up, participants will be assessed at predefined time points for antibiotic-associated adverse events, gastrointestinal symptoms, stool form, treatment adherence, and Helicobacter pylori eradication status. Stool samples will be collected before and after treatment to evaluate faecal IgA levels, the presence of Bacillus strains, and changes in gut microbiota using real-time PCR, ELISA, and 16S rRNA sequencing.

Participants needed: 336
Trial details
Age: 18-65Biological sex: AllType: InterventionalSponsor: Anabio R&DUpdated: Sep 22, 2026Locations: 1
Eligibility criteria

Patients aged 18 to 65 years; [+3]

Active bleeding gastric or duodenal ulcer. [+4]

Status: Recruiting

A Study of the Safety of Vonoprazan Exposure in Pregnant Women and Their Offspring

The main objective of the study is to compare the maternal, fetal, and infant outcomes of pregnant women who are exposed to vonoprazan during pregnancy with outcomes of an internal comparison cohort of pregnant women who are unexposed to vonoprazan during pregnancy but who may be exposed to other products for the treatment of conditions for which vonoprazan may be prescribed.

Participants needed: 728
Trial details
Age: 15-50Biological sex: FemaleType: ObservationalSponsor: Phathom Pharmaceuticals, Inc.Updated: Sep 18, 2026Locations: 1Duration: 12 Months
Eligibility criteria

Women 15 to 50 years of age. [+5]

Occurrence of pregnancy outcome prior to first contact with the virtual research... [+2]

Status: Not yet recruiting

NLR and PLR in H. Pylori-Associated Gastritis

This cross-sectional study aims to evaluate the role of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) as inflammatory markers in patients with Helicobacter pylori-associated gastritis at Assiut University Hospitals.

Participants needed: 90
Trial details
Age: 18+Biological sex: AllType: ObservationalSponsor: Assiut UniversityUpdated: Sep 9, 2026Duration: 1 Day
Eligibility criteria

- Age 18 years or older [+3]

- Hematological diseases [+5]

Status: Recruiting

VA Dual Sequential Therapy

Sequential therapy for Hp was first introduced by Zullo et al. in 2000 and consists of two phases: the first phase involves proton pump inhibitors with one antibiotic, and the second phase involves proton pump inhibitors with two antibiotics. Based on this, the investigators propose a modified sequential therapy, where the first phase uses vonoprazan combined with amoxicillin, and the second phase increases the amoxicillin dosage, forming a high-dose amoxicillin regimen. This new treatment strategy combines the staged nature of sequential therapy with the advantages of high-dose dual therapy, gradually increasing the drug dosage to help patients adapt and reduce side effects (such as nausea, vomiting, and diarrhea), thereby improving patient tolerance. The primary aim of this study is to compare the vonoprazan combined with high-dose amoxicillin sequential therapy with standard dual therapy (14-day regimen) in terms of Hp eradication rates, efficacy, side effect incidence, and patient compliance, to evaluate its improved effectiveness. Additionally, the study will explore the impact of a shortened treatment duration on the modified dual sequential therapy's efficacy for Hp infection. Eligible participants in this study will be randomly assigned to one of the following three treatment groups based on a pre-generated randomization sequence: Control Group: Vonoprazan combined with high-dose amoxicillin dual therapy for 14 days (VADT-14): Vonoprazan 20mg twice daily + Amoxicillin 1g three times daily. Experimental Group 1: Vonoprazan combined with amoxicillin dual sequential therapy for 14 days (VAST-14): Days 1 to 7: Vonoprazan 20mg twice daily + Amoxicillin 1g twice daily. Days 8 to 14: Vonoprazan 20mg twice daily + Amoxicillin 1g three times daily. Experimental Group 2: Vonoprazan combined with amoxicillin dual sequential therapy for 10 days (VAST-10): Days 1 to 5: Vonoprazan 20mg twice daily + Amoxicillin 1g twice daily. Days 6 to 10: Vonoprazan 20mg twice daily + Amoxicillin 1g three times daily.

Participants needed: 600
Trial details
Phase: Phase 4Age: 18-70Biological sex: AllType: InterventionalSponsor: The First Affiliated Hospital with Nanjing Medical UniversityUpdated: Sep 1, 2026Locations: 1
Eligibility criteria

Aged 18-70 years, gender unrestricted. [+3]

Allergy to any of the drugs used in this clinical trial. [+10]

Status: Not yet recruiting

Metronidazole- Versus Tinidazole-Based Bismuth Quadruple Therapy for Helicobacter Pylori Eradication

This randomized, open-label clinical trial will compare two bismuth-containing quadruple therapies for the first-line treatment of Helicobacter pylori infection. Adults aged 18 years or older with confirmed H. pylori infection who have not previously received eradication treatment will be randomly assigned in a 1:1 ratio to receive either a metronidazole-based regimen or a tinidazole-based regimen for 14 days. Both regimens will also include esomeprazole, tetracycline, and bismuth subcitrate. The main purpose of the study is to determine whether the tinidazole-based regimen is not inferior to the metronidazole-based regimen in achieving successful H. pylori eradication. Eradication will be assessed after treatment using a carbon-13 urea breath test or an endoscopic urease test. The study will also compare adverse effects and treatment tolerability between the two groups. The results may help clinicians select the more appropriate nitroimidazole for bismuth quadruple therapy in routine clinical practice.

Participants needed: 600
Trial details
Age: 18+Biological sex: AllType: InterventionalSponsor: University of Medicine and Pharmacy at Ho Chi Minh CityUpdated: Aug 5, 2026Locations: 1
Eligibility criteria

Adults aged 18 years or older. [+2]

Pregnancy or breastfeeding. [+7]

Status: Not yet recruiting

Pylori Duo for Adjunctive Treatment and Prevention of Recurrence of Helicobacter Pylori Infection

This randomized, double-blind, placebo-controlled, single-center clinical trial will evaluate the efficacy and safety of Pylori Duo as an adjunctive treatment in adult patients with confirmed Helicobacter pylori infection. Approximately 140 participants will be randomized to receive standard quadruple therapy (omeprazole plus Pylera®) combined with either placebo or Pylori Duo for 10 days, followed by placebo or Pylori Duo for 3 months. The primary objective is to assess the effect of Pylori Duo on gastrointestinal adverse effects associated with standard eradication therapy. Secondary objectives include assessment of H. pylori eradication, recurrence at 3 and 12 months, gastrointestinal symptoms, quality of life, and safety.

Participants needed: 140
Trial details
Age: 18-70Biological sex: AllType: InterventionalSponsor: Gala Servicios Clinicos S.L.Updated: Jul 27, 2026Locations: 1
Eligibility criteria

Adults aged 18 to 70 years. [+3]

Significant underlying conditions that, in the opinion of the treating physician... [+8]

Status: Recruiting

Study on the Effect of Fecal Microbiota Transplantation on Eradication of Refractory Helicobacter Pylori Infection

To determine whether regulating the gut microbiota can contribute to the eradication of refractory H. pylori infection.

Participants needed: 10
Trial details
Phase: Phase 4Age: 18-80Biological sex: AllType: InterventionalSponsor: Sichuan Provincial People's HospitalUpdated: Jul 15, 2026Locations: 1
Eligibility criteria

1. Ages 18-70 [+2]

1. Antibiotics and bismuth were taken within 4 weeks before this treatment; Or h... [+8]

Status: Recruiting

Application of Artificial Intelligence on the Diagnosis of Helicobacter Pylori Infection and Premalignant Gastric Lesion

The aim of this study is to evaluate the impact of artificial intelligence (AI) assistance during routine upper endoscopy on gastric cancer-specific mortality. We hypothesize that AI-assisted endoscopic interpretation can further reduce gastric cancer-related mortality through two mechanisms: (1) improved detection of H. pylori infection, facilitating timely eradication therapy and subsequent prevention of gastric carcinogenesis; and (2) earlier identification of premalignant gastric conditions, enabling appropriate surveillance endoscopy and earlier detection of gastric cancer. The primary endpoint is gastric cancer-specific mortality.

Participants needed: 6,000
Trial details
Age: 20-80Biological sex: AllType: ObservationalSponsor: National Taiwan University HospitalUpdated: Jun 24, 2026Locations: 1
Eligibility criteria

Age 20-80 [+1]

Status: Not yet recruiting

Vonoprazan High-Dose Dual VS Levofloxacin Concomitant

This is a randomized controlled trial comparing the efficacy and safety of two vonoprazan-based regimens: high-dose dual therapy (vonoprazan plus a single antibiotic) versus triple therapy (vonoprazan plus two antibiotics) for the treatment of H. pylori infection). Participants will be randomly assigned to receive either regimen for 14 days. The primary outcome is eradication rate , and secondary outcomes include adverse events and treatment adherence.

Participants needed: 150
Trial details
Phase: Phase 4Age: 18-80Biological sex: AllType: InterventionalSponsor: Damascus HospitalUpdated: Jun 3, 2026Locations: 1
Eligibility criteria

Age ≥ 18 years and ≤ 80 years (adjust upper limit as needed) [+5]

History of allergy or hypersensitivity to vonoprazan, amoxicillin, clarithromyci... [+8]

Status: Recruiting

Simplified Dual Regimen Guided by Fecal Clarithromycin Resistance Gene Detection for First-line H. Pylori Eradication

To investigate the efficacy, safety, and compliance of a simplified strategy using vonoprazan plus clarithromycin for first-line treatment in patients with Helicobacter pylori infection, among those infected with strains without clarithromycin resistance gene mutations based on fecal clarithromycin resistance gene detection.

Participants needed: 70
Trial details
Age: 18-70Biological sex: AllType: InterventionalSponsor: Peking University First HospitalUpdated: Apr 30, 2026Locations: 1
Eligibility criteria

Aged 18-70 years; [+2]

Pregnant or lactating women [+4]

Status: Recruiting

Tegoprazan-containing Sequential for H. Pylori

As H. pylori eradication, the investigators prepared a randomized controlled clinical trial whether tegoprazan-containing 10-day sequential treatment was effective compared to conventional PPI-containing 10-day sequential eradication therapy

Participants needed: 400
Trial details
Age: 18+Biological sex: AllType: InterventionalSponsor: Seoul National University Bundang HospitalUpdated: Apr 28, 2026Locations: 1
Eligibility criteria

congestive heart failure, NYHA III or IV [+4]

Status: Recruiting

Vonoprazan-based Versus Esomeprazole-based Triple Therapy for Helicobacter Pylori Eradication

The goal of this clinical trial is to compare the efficacy and safety of vonoprazan-based levofloxacin-containing triple therapy with esomeprazole-based levofloxacin-containing triple therapy for eradication of Helicobacter pylori infection in adults with dyspepsia. The main questions it aims to answer are whether vonoprazan-based triple therapy achieves a higher eradication rate of H. pylori, whether it provides greater improvement in dyspeptic symptoms, and what adverse effects are associated with each regimen. Researchers will compare the two treatment regimens to determine which is more effective for H. pylori eradication. Participants with confirmed H. pylori infection will be randomly assigned to receive either vonoprazan-based or esomeprazole-based triple therapy for 14 days. Four weeks after completion of therapy, participants will undergo repeat stool antigen testing to assess eradication. Drug compliance, adverse effects, and dyspeptic symptom scores will be recorded during follow-up. Participants with endoscopic mucosal lesions at baseline will undergo follow-up endoscopy for reassessment.

Participants needed: 80
Trial details
Phase: Phase 4Age: 18+Biological sex: AllType: InterventionalSponsor: Bangabandhu Sheikh Mujib Medical University, Dhaka, BangladeshUpdated: Apr 22, 2026Locations: 2
Eligibility criteria

Age ≥ 18 years [+2]

Treatment with a proton pump inhibitor, H2-receptor antagonist within the last 2... [+12]

Status: Recruiting

Efficacies of Susceptibility-guided vs Empiric Therapy for Rescue Treatment of Helicobacter Pylori Infection

The prevalence of H. pylori antibiotic resistance has reached an alarming level worldwide. Antibiotic stewardship programs should be urgently developed and implemented. However, H. pylori antimicrobial susceptibility testing (AST) is rarely offered, making local resistance patterns not easily available. Guideline-recommended empiric therapies (GR-ET) may no longer reliably achieve high cure rate in the era of increasing antibiotic resistance. susceptibility-guided tailored therapy (SG-TT) may be a good choice to solve this problem. The aims of this study are: 1. to compare the efficacy of SG-TT with GR-ET as rescue regimens for H. pylori eradication; 2. to compare the patient adherence and adverse effects of these treatment regimens; 3. to investigate factors that may influence H. pylori eradication by these treatment regimens.

Participants needed: 450
Trial details
Phase: Phase 4Age: 20+Biological sex: AllType: InterventionalSponsor: National Taiwan University HospitalUpdated: Apr 15, 2026Locations: 1
Eligibility criteria

pregnant or nursing woman; [+5]

Status: Not yet recruiting

Predicting Peptic Complications Using H. Pylori Serology and Gastric Ultrasound

This observational study aims to evaluate whether combining a simple blood test (H. pylori serology) with a non-invasive abdominal ultrasound can accurately predict severe complications in patients with peptic ulcer disease (PUD). Peptic ulcer complications, such as stomach bleeding or perforation, are serious and typically require an invasive procedure called an upper endoscopy for diagnosis and treatment. Researchers want to find out if these two non-invasive tests can be used together to create a reliable risk-scoring system. This system would help doctors quickly identify which patients are at a high risk for complications and need an urgent endoscopy, compared to those who are at a lower risk and can be safely monitored without the invasive procedure. The study will include adult patients presenting with stomach symptoms (like pain, nausea, or heartburn), as well as those with suspected or confirmed peptic ulcer disease. Participants will provide a blood sample to check for H. pylori antibodies and undergo a standard, painless abdominal ultrasound to examine the thickness of their stomach wall. An upper gastrointestinal endoscopy will be performed if it is clinically necessary as part of the patient's standard medical care.

Participants needed: 230
Trial details
Age: 18+Biological sex: AllType: ObservationalSponsor: Assiut UniversityUpdated: Mar 9, 2026
Eligibility criteria

Adult patients (age ≥18 years) presenting with dyspeptic symptoms (epigastric pa... [+4]

Previous gastric surgery (gastrectomy, vagotomy). [+8]

Status: Recruiting

H. Pylori Eradication With Argon Plasma During Endoscopy

The objective of the study is to investigate the efficacy and safety of an argon plasma-based therapy - HEAPE - in treating H. pylori infections during endoscopic procedures. By filling the stomach with sodium chloride solution that is treated with APC (PAL), the Investigators hypothesize a significant reduction in H. pylori. The use of PAL instead of direct application of APC allows for a broader and more homogeneous application throughout the stomach and a faster procedure time, as the fluid bypasses the thermal effects typically associated with higher electrical power settings and focuses on the bactericidal action of PAL. It is a procedure that does not involve thermal ablation of the stomach lining. Thus, side effects should be expected to be as low as possible. Two different PAL generation modalities will be compared in this study: 1. HEAPE direct: This modality is the direct generation of PAL in the stomach. The stomach is filled with sodium chloride solution which is then treated with APC. With HEAPE direct a potential decrease of reactive species is avoided, as the treatment happens directly at the intended location in the H. pylori infected stomach. 2. Pre-HEAPE: This modality features the treatment of sodium chloride with APC outside of the patient in a sterile container. After the APC treatment, the generated PAL is administered into the stomach with a syringe through the working channel of the endoscope. Pre-HEAPE allows an easier handling of the APC probe as the treatment of the sodium chloride solution can be done without an endoscope. To evaluate the immediate effect of this novel treatment approach the metabolic activity of H. pylori will be assessed using a urea breath test (UBT) before and after treatment. A reduction in H. pylori levels can be detected by a reduction in urease activity in the breath test. After the HEAPE procedure, patients are treated with antibiotics (best practice) as they would be under normal circumstances. Four weeks after treatment, another UBT is performed to determine if H. pylori has been eradicated or if additional antibiotic treatment is indicated. This two-arm, randomized, pilot, single-center, prospective clinical study is designed to evaluate the safety, tolerability and proof of concept that PAL has the ability to eradicate or reduce the bacterial load of H. pylori in humans.

Participants needed: 20
Trial details
Age: 18+Biological sex: AllType: InterventionalSponsor: Christopher C. Thompson, MD, MScUpdated: Mar 2, 2026Locations: 1
Eligibility criteria

Subjects must be 18 years or older [+4]

Patients actively undergoing H.pylori eradication therapy treatment with antibio... [+6]

Status: Not yet recruiting

Fecal Molecular Susceptibility-guided Hp Rescue Therapy

The goal of this clinical trial is to evaluate the eradication efficacy and health economic benefits of individualized regimens guided by fecal molecular susceptibility testing with 7-day and 14-day courses in the rescue treatment of Helicobacter pylori infection. The main questions it aims to answer are: 1. What is the H. pylori eradication rate of the 7-day versus 14-day individualized regimens? 2. What are the safety, adherence, and cost-effectiveness of the 7-day versus 14-day individualized regimens? Researchers will compare the 7-day course group and the 14-day course group to see if the 7-day course is non-inferior to the 14-day course in terms of eradication rate. Participants will: 1. Undergo fecal H. pylori drug resistance gene testing 2. Receive randomized assignment to either 7-day or 14-day individualized treatment based on drug susceptibility results 3. Complete follow-up visits at 1 week and 4-8 weeks after stopping treatment for adverse event monitoring and 13C-urea breath test

Participants needed: 290
Trial details
Phase: Phase 4Age: 18-75Biological sex: AllType: InterventionalSponsor: Shanghai Zhongshan HospitalUpdated: Feb 12, 2026Locations: 4
Eligibility criteria

Voluntarily participate in this clinical study; fully understand, be informed ab... [+3]

Individuals with a known allergy to the medication. [+6]

Status: Recruiting

Efficacies of Bismuth-amoxicillin-vonoprazan Triple Therapy and Bismuth Quadruple Therapy

(1) To compare the efficacy and safety of a 14-day bismuth-amoxicillin-vonoprazan triple therapy versus a 14-day bismuth-based quadruple therapy as first-line treatments for H. pylori infection, and (2) To investigate the influence of H. pylori antibiotic resistance, along with host CYP3A4, CYP2C19, and IL-1B -511 genotypes, on the eradication efficacy of H. pylori therapies.

Participants needed: 552
Trial details
Age: 18+Biological sex: AllType: InterventionalSponsor: Kaohsiung Medical UniversityUpdated: Jan 22, 2026Locations: 1
Eligibility criteria

Subjects with Helicobacter pylori infection

Subjects with known hypersensitivity to the study drug. [+5]

Status: Recruiting

P-CABs-based Bismuth Quadruple Therapy for Helicobacter Pylori Eradication

Bismuth-containing quadruple therapy was recommended as a first-line treatment for Helicobacter pylori infection. This study aimed to compare real-world outcomes of various potassium-competitive acid blockers (P-CABs) -based bismuth quadruple regimens and identify factors influencing treatment failure. A multicenter cohort study was conducted and study outcomes included eradication rates and incidence of adverse events.

Participants needed: 1,730
Trial details
Age: 18-70Biological sex: AllType: ObservationalSponsor: Yueyue LiUpdated: Dec 23, 2025Locations: 1Duration: 8 Weeks
Eligibility criteria

patients aged 18-70 years, regardless of gender; [+2]

patients with incomplete medical records, including missing treatment details, a... [+1]

Status: Recruiting

A "Screen and Treat" Helicobacter Pylori Eradication Trial in Adolescents in Three Regions of Chile

Gastric cancer remains a global health problem, and Chile has one of the highest GC mortality rates in the region. Helicobacter pylori (H. pylori) infection is ubiquitous in Chilean adults, and it constitutes the main cause of GC worldwide. A long-term process occurs from premalignant lesions to carcinoma. H. pylori eradication during early stages of disease significantly impacts outcomes, favoring survival, disease reversal and molecular changes, which supports a "screen and treat" strategy in asymptomatic populations in areas with intermediate-to-high GC prevalence. The Investigators' previous research has shown that H. pylori infection is acquired in early childhood with low rates of spontaneous eradication. A pilot treatment study in a subset of school-aged asymptomatic children showed a high rate of successful eradication (\>95%), good tolerance, and was associated with a decrease in serum biomarkers of gastric damage (pepsinogen I and II). Based on the results of these studies, the Investigators propose to advance towards the next stage of this research process: a "screen and treat" strategy. The current trial starts with a Screening phase testing up to 1000 asymptomatic adolescents 14-18 years of age from 3 cities of Chile (Colina, Temuco and Coyhaique), to find a total of 210 persistently-infected participants. Persistently-infected adolescents will be included in a Second phase of this trial: A randomized, case-control, non-blinded study to either receive antimicrobial treatment targeting H. pylori eradication (cases) or no treatment (controls). A subset of 60 non-infected adolescents will be followed-up in matched times. This aims to provide evidence on the effect of treatment on clinical outcomes and serum biomarkers related to gastric damage, as well as composition and antimicrobial resistance of gut microbiota. The Investigators expect that eradication therapy will be successful in \>90% of persistently infected adolescents, with reinfection rates not surpassing 15% in a 2-3 year period, and to be associated with a decrease in clinical findings indicative of gastric disease, and a decrease in serum biomarker indicative of "gastric damage".

Participants needed: 500
Trial details
Age: 14-18Biological sex: AllType: InterventionalSponsor: Miguel O'Ryan GallardoUpdated: Dec 17, 2025Locations: 3
Eligibility criteria

Healthy teenagers 14-18 years of age from Colina, Temuco or Coyhaique [+2]

Teenagers not consenting to treatment will be invited to continue as non-treated... [+7]

Status: Recruiting

The GAstric Precancerous Conditions Study

Gastric cancer afflicts 27,000 Americans annually and carries a dismal prognosis. One reason for poor outcomes is late diagnosis, as the majority of gastric cancers in the United States are diagnosed at a relatively advanced stage where curative resection is unlikely. Gastric precursors (such as atrophic gastritis and intestinal metaplasia) are precancerous changes to the stomach mucosa which increases risk for subsequent gastric cancer. The Gastric Precancerous Conditions Study (GAPS) is an observational study of patients at elevated risk for gastric cancer. Investigators seek to recruit patients from endoscopy unit of Stanford Health Care, a large academic network of hospitals and clinics serving Northern California. Investigators will recruit patients who are both symptomatic (e.g. dyspepsia) and asymptomatic (e.g. referred for screening), and individuals both with known precursor lesions (such as intestinal metaplasia) or at high risk for carrying precursor lesions. A component of the study is long-term follow-up of individuals with gastric precursors. This is to understand their risk factors for histologic progression and regression. During both index and subsequent endoscopies, the study team will collect biospecimens (e.g. blood, saliva, gastric tissue).

Participants needed: 600
Trial details
Age: 35-84Biological sex: AllType: ObservationalSponsor: Stanford UniversityUpdated: Dec 16, 2025Locations: 1
Eligibility criteria

Cannot give consent [+3]

Status: Not yet recruiting

Effect of H. Pylori Eradication on The Improvement of Gastrointestinal Symptoms

This study aims to evaluate the effect of Helicobacter pylori eradication on gastrointestinal symptoms in adult patients. H. pylori infection is a common cause of dyspepsia and other upper gastrointestinal complaints. The trial will assess whether successful eradication therapy leads to significant improvement in symptoms compared to baseline. Adult patients diagnosed with H. pylori infection will receive standard eradication treatment, and symptom changes will be monitored using validated questionnaires over a defined follow-up period.

Participants needed: 100
Trial details
Age: 18+Biological sex: AllType: ObservationalSponsor: Amany Usama Ahmed ArafaUpdated: Dec 16, 2025
Eligibility criteria

Adults aged 18 years and older. [+4]

Age less than 18 years. [+6]

Status: Recruiting

Saccharomyces Boulardii Combined With Bismuth Quadruple Therapy for Helicobacter Pylori Rescue Treatment

This study aims at evaluating efficacy and safety of Saccharomyces boulardii combined with bismuth-containing quadruple Therapy versus bismuth-containing quadruple Therapy(bismuth#esomeprazole#tetracycline and furazolidone) in H. pylori rescue therapy. It is hypothesized that Saccharomyces boulardii combined with bismuth-containing quadruple Therapy is superior to bismuth-containing quadruple Therapy. Patients with confirmed failure of H. pylori eradication will be randomized to one of the treatments described above. At week 6 follow-up visits, a urea breath test#rapid urease test or helicobacter pylori stool antigen test will be performed to confirm eradication.

Participants needed: 1,248
Trial details
Phase: Phase 4Age: 18-75Biological sex: AllType: InterventionalSponsor: Yongquan ShiUpdated: Dec 2, 2025Locations: 1
Eligibility criteria

Age between 18~75, both gender. [+2]

Patients who have previously used tetracycline and furazolidone antibiotics to e... [+13]

Status: Recruiting

Treatment Efficacy of Regimens With and Without Bismuth in Children With Helicobacter Pylori-Associated Peptic Ulcer Disease

The goal of this clinical trial is to learn if including bismuth in the treatment helps heal stomach and duodenal ulcers caused by Helicobacter pylori (H. pylori) in children. The main questions it aims to answer are: * Does a treatment plan with bismuth work better than a plan without bismuth to clear the infection? * Is the bismuth plan more cost-effective while still safe and effective? Researchers will compare two treatment groups to see which works better. Participants will: * Take one of the two assigned treatment plans (with or without bismuth) for the standard treatment duration * Visit the clinic for checkups and tests to confirm infection clearance and monitor side effects * Keep a diary of symptoms, medication use, and any side effects

Participants needed: 80
Trial details
Age: 5-15Biological sex: AllType: InterventionalSponsor: Can Tho University of Medicine and PharmacyUpdated: Dec 2, 2025Locations: 1
Eligibility criteria

Diagnosed with gastritis or peptic ulcer disease by upper gastrointestinal endos... [+2]

Allergic to any of the medications in the treatment regimen. [+2]