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The Role of Irritable Bowel Syndrome in Lactose Intolerance (LION)

The Role of Irritable Bowel Syndrome in Lactose Intolerance (LION Trial): Protocol of a Multicentre Randomized Controlled Clinical Trial

Status
Not yet recruiting
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05100719
Acronym
LION
Enrollment
200
Registered
2021-10-29
Start date
2022-09-30
Completion date
2026-12-31
Last updated
2021-10-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Irritable Bowel Syndrome, Lactose Intolerance, Lactose Malabsorption

Keywords

irritable bowel syndrome, lactose intolerance, lactose malabsorption, lactase, simethicone, alverine-citrate, placebo

Brief summary

Irritable bowel syndrome (IBS) is a functional gastrointestinal disease. There is no well-defined pharmacological treatment. This clinical trial is a prospective, double-blind, two-armed randomized controlled, single-center trial. It is created to examine the role of IBS in patients with lactose intolerance. IBS patients undergo lactose H2 breath test (LHBT) and lactose tolerance test (LTT). Those with positive LTT and LHBT will be randomized into two groups: alverine-citrate + simethicone and lactase group (1) or alverin-citrate + simethicone with the placebo group (2). The goal of this study is to compare the lactase enzyme with placebo in IBS patients with lactose intolerance.

Detailed description

Irritable bowel syndrome (IBS) is one of the most frequently diagnosed gastroenterological disorders and can lead to significant deterioration of quality of life and an increase in health care and societal costs. Patients with lactose intolerance are unable to fully digest lactose caused by lactose malabsorption. The undigested lactose moves into the large intestine, fermented by bacteria, and causes bloating, gas, and diarrhea symptoms. The two, most frequently used diagnostic methods are the lactose H2 breath test (LHBT) and the lactose tolerance test (LTT). The restriction of lactose input or the replacement of the lactase enzyme can lead to the relief of the symptoms. Lactose intolerance is a common disorder among patients with IBS, it is more frequent than in the general population. There are no studies that assess the link between lactose intolerance and IBS. Our primary objective is the examination of the relationship between lactose intolerance and IBS with or without the replacement of lactase enzyme. Our secondary objectives are to compare the lactase/beta-galactosidase enzyme replacement with placebo with the evaluation of a TSS (Total symptom score), VAS (Visual Analog Scale), QoL (Quality of life) questionnaires. The other secondary outcomes are to compare the severity of baseline symptoms during and after lactose administration. Patients diagnosed with IBS according to the Rome IV criteria will test with LTT and LHBT. Who has positive LTT and LHBT will randomize into two groups: (1) alverine-citrate + simethicone and lactase; (2) alverin-citrate + simethicone with placebo.

Interventions

DRUGalverine-citrate + simethicone and lactase

Patients who randomized in the first arm are treated with alverine-citrate + simethicone and lactase.

DRUGalverin-citrate + simethicone with placebo

Patients in the second arm receive alverin-citrate + simethicone with placebo without lactase.

Sponsors

University of Pecs
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Intervention model description

LION is a two-armed, randomized, double-blind, placebo-controlled, two-phase clinical trial. In the first phase, we will enroll 100 patients, the allocation ratio will be 1:1 (50 patinets in each arm). Then, an interim analysis will be performed to determine the appropriate sample size. During the interim analysis, if there is already significant difference (p\<0.0294) between the arms, the recruitment will be considered completed; otherwise, recruitment will continue until the desired sample size is reached. If there is no hope for ascertaining significance, the study will be stopped.

Eligibility

Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
No

Inclusion criteria

* age 18-80 years * patients diagnosed with irritable bowel syndrome based on the ROME IV. criteria * positive LHBT (lactose H2 breath test) and LTT (lactose tolerance test) results * negative abdominal ultrasound/CAT scan/MRI results within one year * signed the informed consent

Exclusion criteria

* organic gastroenterological disorders which can explain symptoms (e.g. positive serological screening: anti-gliadin IgG / IgA, anti-tissue transglutaminase IgG / IgA, high level of fecal calprotectin tested by endoscopy or positive colonoscopy for IBD, currently active diverticulitis * Alarm symptoms: fever (\> 38 Co), anaemia (Hgb \< 120 g/l), unintended weight loss (\> 4.5 kg / 3 months), gastrointestinal bleeding (hematemesis, hematochesia, melena) * cardiac failure (NYHA III-IV) * liver cirrhosis (Child-Pugh C) * active malignancy * major abdominal surgery in the history * pregnant or breastfeeding women * any circumstances which can lead to false results of LHBT and LTT: cigarette smoking or physical exercise within 2 hours before the test, ingestion of dietary fibers on the evening before the test, recent use of antibiotics, lung disease, baseline H2 concentration in the exhaled air is higher than 20 ppm, not properly treated diabetes mellitus, following lactose restricted or another special diet within 1 week prior to study enrolment (ingestion of less than 12 g lactose - less than 250 ml milk - per day) * small intestinal bacterial overgrowth (SIBO): if there is a rapid increase of H2 level in the exhaled air (≥20 ppm above baseline within 90 minutes), SIBO is suspected and antibiotic therapy will be started (peroral rifaximin for 5 days) after negative Helicobacter pylori serology. After this procedure, lactulose H2 breath test will be performed to exclude SIBO (≥20 ppm H2 rise only after 90 min). In case of negative lactulose H2 breath test, another LHBT will be carried out * slow oro-cecal transit: clinical signs and typical findings on the tests (the LHBT is normal, but the increase of blood glucose level is less than 1.1 mmol/l and/or no H2 rise during lactulose H2 breath test) * milk allergy (positive IgE test)

Design outcomes

Primary

MeasureTime frameDescription
change of the symptoms measured by TSS (total symptom score)The one- and two-week total symptom score (TSS) change compared to baseline value.The primary outcome is the number of enrolled patients with significant improvement in each treatment arm. Significant improvement is considered if there is \>50% reduction in the TSS, compared to the baseline symptoms.

Secondary

MeasureTime frameDescription
the absence of a bowel movementThe three time points at which the measurement is assessed are the time of enrollment, after 1 and 2 weeks.The absence of a bowel movement is accompanied by an improvement of ≥30 mm in the VAS (visual analogue scale) for the worst abdominal pain.
relief of IBS-related bloatingThe three time points at which the measurement is assessed are the time of enrollment, after 1 and 2 weeks.The number of patients with acceptable relief of IBS-related bloating determined by a questionnaire, from the response (yes or no) compare to the baseline IBS-related bloating.
improvement in stool consistencyThe two time points at which the measurement is assessed are the time of enrollment and after 2 weeks.stool consistency score of \<5, according to the Bristol stool chart
incidence of Small intestinal bacterial overgrowth (SIBO)At the time of patient enrollment and after two weeks of treatments this test will be carried out again.Early (within 90 minutes), significant (≥20 ppm) H2 rise during LHBT or lactulose breath test compared to the baseline value.
results of LHBT and LTTAt the time of patient enrollment and after two weeks of treatments LHBT and LTT will be carried out again.Results of LHBT (lactose H2 breath test) and LTT (lactose tolerance test).
Onset and duration of relief of bloatingThe three time points at which the measurement is assessed are the time of enrollment, after 1 and 2 weeks.Onset and duration of relief of bloating is measured by a questionnaire.

Countries

Hungary

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026