Evaluation of LacTEST for the Diagnosis of Hypolactasia in Adults and Elderly Patients Presenting With Clinical Symptoms of Lactose Intolerance

Study Overview
=================
Brief Summary
-----------------
The purpose of this study is to evaluate both the impact of LacTEST on diagnostic thinking and on patient management, and its reproducibility (Test-Retest), for the diagnosis of hypolactasia in adults and elderly patients presenting with clinical symptoms of lactose intolerance.

Official Title
-----------------
Evaluation of the Impact of LacTEST on Diagnostic Thinking and on Patient Management, and of the Reproducibility (Test-Retest), for the Diagnosis of Hypolactasia in Adults and Elderly Patients Presenting With Clinical Symptoms of Lactose Intolerance

Conditions
-----------------
Lactose Intolerance

Intervention / Treatment
-----------------
* Drug: gaxilose
* Dietary Supplement: lactose


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Adults of either sex, between 18 and 70 years old. Capacity for understanding and giving the informed consent to participate in this study. Patients with clinical suggestive of lactose intolerance, primary or secondary, who have not been diagnosed and that fulfil the requirements allowed by the gaxilose summary of product characteristics (SmPC). Exclusion Criteria: Pregnant women or breast-feeding women. Unable or reticent to give the informed consent or to comply with the study requirements. Patients with glomerular filtration rate (GFR) less than 90 ml/min/1.73m2. Portal hypertension: ascites, cirrhosis. Medical records of total gastrectomy and/or vagotomy. Patients diagnosed with myxedema. Patients with Diabetes Mellitus. Patients who are participating or have participated in any clinical trial within the 3 months previous to their inclusion in the study. Patients who are drug abuse consumers. Patients under treatment with antibiotics, sulphamides and antiparasitics, who cannot suspend the treatments 7 days prior to the performance of the hydrogen breath test. Patients with any recognized and already existing disorder that might interfere with the any of the lactose intolerance diagnosis tests. Patients who have taken aspirin of indomethacin in the 48h preceding the performance of the Gaxilose test.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: LacTEST<br>0,45 g of gaxilose po, once, per diagnostic test performed. | Drug: gaxilose<br>* After gaxilose administration, urine collection, cuantification (firstly from 0 to 4 hours, and total urine from 0 to 5 hours), and xilose cuantification afterwards.<br>* Other names: LacTEST;|
| Active Comparator: Hydrogen Breath Test<br>25 to 50 g of lactose po, once, per diagnostic test performed. | Dietary Supplement: lactose<br>* After lactose administration, expired hydrogen measurement at pre-specified intervals.<br>* Other names: Hydrogen Breath Test (HBT);|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual Analogical Scale | The primary objective is to demonstrate non-inferiority of gaxilose test, compared with Hydrogen Breath Test (HBT) using a validated method (VAS results pre and post-test), on the impact on diagnostic thinking for the diagnosis of hypolactasia. | Through study completion, up to 10 months. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Physician's Questionnaire | To demonstrate non-inferiority of gaxilose test, compared with Hydrogen Breath Test (HBT), on the impact on patient management for the diagnosis of hypolactasia, through a Physician's Qestionnaire. | Through study completion, up to 10 months. | 
| Intraclass Correlation Coefficient | To demonstrate gaxilose test reproducibility [ICC (2,1)] with urine accumulated from 0-4h after gaxilose administration, and with urine accumulated from 0-5h after gaxilose administration. | Through study completion, up to 10 months. | 
| Number of participants with treatment-related adverse events as assessed by the most recent version of MedDRA thesaurus. | To assess the safety profile of both tests performed, by assessing the frecuency of treatment-related AEs. | Through study completion, up to 10 months. |