Effect of Glycine in Cystic Fibrosis

This study has been terminated.
(Some of the researchers finished their participation in the study.)
Sponsor:
Collaborators:
Hospital Infantil de Mexico Federico Gomez
Instituto Mexicano del Seguro Social
Information provided by (Responsible Party):
Mario H. Vargas, Instituto Nacional de Enfermedades Respiratorias
ClinicalTrials.gov Identifier:
NCT01417481
First received: August 15, 2011
Last updated: October 21, 2014
Last verified: October 2014

August 15, 2011
October 21, 2014
March 2012
September 2013   (final data collection date for primary outcome measure)
  • Serum Concentration of Inflammatory Biomarkers (Other Than TNF-alpha) [ Time Frame: 8 weeks ] [ Designated as safety issue: No ]
    To correct for the baseline variability, all measurements were expressed as percentage of baseline (value at week 8 with respect to baseline value [beginning of the glycine or placebo period, respectively]). Then, percentages were log-transformed to adjust to a normal distribution.
  • Sputum Concentration of Inflammatory Biomarkers (Other Than IL-6 and G-CSF) [ Time Frame: 8 weeks ] [ Designated as safety issue: No ]
    To correct for the baseline variability, all measurements were expressed as percentage of baseline (value at week 8 with respect to baseline value [beginning of the glycine or placebo period, respectively]). Then, percentage change was log-transformed to adjust to a normal distribution.
  • Serum Concentration of Inflammatory Biomarkers (TNF-alpha) [ Time Frame: 8 weeks ] [ Designated as safety issue: No ]
    To correct for the baseline variability, all measurements were expressed as percentage of baseline (value at week 8 with respect to baseline value [beginning of the glycine or placebo period, respectively]). Then, percentages were log-transformed to adjust to a normal distribution.
  • Sputum Concentration of Inflammatory Biomarkers (IL-6) [ Time Frame: 8 weeks ] [ Designated as safety issue: No ]
    To correct for the baseline variability, all measurements were expressed as percentage of baseline (value at week 8 with respect to baseline value [beginning of the glycine or placebo period, respectively]). Then, percentage change was log-transformed to adjust to a normal distribution.
  • Sputum Concentration of Inflammatory Biomarkers (G-CSF) [ Time Frame: 8 weeks ] [ Designated as safety issue: No ]
Decrease of serum and sputum concentrations of inflammatory biomarkers in children with cystic fibrosis. [ Time Frame: 8 weeks ] [ Designated as safety issue: Yes ]
To determine whether a daily oral supplement of 0.5 g/kg glycine during 8 weeks significantly diminish the serum and sputum concentrations of inflammatory biomarkers in children with cystic fibrosis, including IL-1β, IL-6, IL-8, TNF-α, myeloperoxidase.
Complete list of historical versions of study NCT01417481 on ClinicalTrials.gov Archive Site
  • Clinical Data (Other Than Sputum Production, Dyspnea and Global Symptoms) [ Time Frame: 8 weeks ] [ Designated as safety issue: Yes ]

    To correct for the baseline variability, all measurements were expressed as percentage of baseline (value at week 8 with respect to baseline value [beginning of the glycine or placebo period, respectively]).

    Each respiratory symptom (Cough severity, Sputum features, Appetite, Dyspnea, and Energy perception) was evaluated in a 5-options Likert scale, ranging from 1 (better) to 5 (worse). The total score was computed by the simple sum of the five symptoms.

  • Improvement of Score for Sputum Production, Dyspnea and Global Symptoms [ Time Frame: 8 weeks ] [ Designated as safety issue: Yes ]

    To correct for the baseline variability, all measurements were expressed as percentage of baseline (value at week 8 with respect to baseline value [beginning of the glycine or placebo period, respectively]).

    In the symptoms questionnaire, each respiratory symptom (Cough severity, Sputum features, Appetite, Dyspnea, and Energy perception) was evaluated in a 5-options Likert scale, ranging from 1 (better) to 5 (worse). The total score was computed by the simple sum of the five symptoms.

  • Improvement in Pulse Oximetry, FEV1/FVC, and FEF50. [ Time Frame: 8 weeks ] [ Designated as safety issue: Yes ]
    To correct for the baseline variability, all measurements were expressed as percentage of baseline (value at week 8 with respect to baseline value [beginning of the glycine or placebo period, respectively]).
  • Improvement in FEV1, FEF25, and FEFmax [ Time Frame: 8 weeks ] [ Designated as safety issue: Yes ]
    To correct for the baseline variability, all measurements were expressed as percentage of baseline (value at week 8 with respect to baseline value [beginning of the glycine or placebo period, respectively]).
  • Other Spirometric Variables [ Time Frame: 8 weeks ] [ Designated as safety issue: Yes ]
    To correct for the baseline variability, all measurements were expressed as percentage of baseline (value at week 8 with respect to baseline value [beginning of the glycine or placebo period, respectively]).
Improvement of respiratory symptoms, sputum production, and spirometric variables [ Time Frame: 8 weeks ] [ Designated as safety issue: Yes ]
To determine whether a daily oral supplement of 0.5 g/kg glycine during 8 weeks improve respiratory symptoms, sputum production, and spirometric variables.
Not Provided
Not Provided
 
Effect of Glycine in Cystic Fibrosis
Evaluation of the Capability of a Glycine Oral Supplement for Diminishing Bronchial Inflammation in Children With Cystic Fibrosis

The aim of this study is to evaluate if glycine, orally administered in a daily dose of 0.5 g/kg during 8 weeks, can ameliorate the airway inflammation in children with cystic fibrosis, as compared with placebo. During all of the study children will receive their usual treatment for cystic fibrosis.

Background. Cystic fibrosis (CF) is a genetic disorder caused by a mutation in a gene that codifies for a chloride channel named "cystic fibrosis transmembrane regulator" (CFTR). In the lungs this results in thick and dehydrated mucus that tends to cause obstruction of the bronchial lumen. Neutrophils and proinflammatory substances have been detected in bronchoalveolar lavage fluid of children with CF who have no bacterial infection. This inflammation conditions a vicious circle in which airways are colonized by bacteria that further increase inflammation. Persistent inflammation leads to irreversible changes in airways, which become distorted. Therefore, a key step in CF treatment is reduction of airway inflammation, for which long-term use of corticosteroids, ibuprofen or macrolides may be indicated.

Glycine and its antiinflammatory effect. Glycine is the most simple aminoacid, but it is also an agonist of the glycine receptors (GlyR) that, when activated, cause that cells such as Kupffer cells, alveolar macrophages and neutrophils decrease their sensitivity to proinflammatory agents. Orally administered glycine has been used for some illnesses, and it has been noticed that it is well tolerated. Considering that children with CF have an intense inflammatory process in the airways, here we propose to use glycine as antiinflammatory agent.

Problem statement. Can a glycine oral supplement decrease the airway inflammation in children with CF?

Hypothesis. Compared with placebo, a daily supplement of glycine administered for 8 weeks to children with CF produce a statistically significant decrease of bronchial inflammation, measured by the concentration of neutrophils and inflammatory substances in sputum and peripheral blood, as well as by respiratory symptoms and spirometry.

Main objective: To determine whether a daily supplement of 0.5 g/kg glycine for 8 weeks significantly decrease the concentration, including neutrophils, interleukin(IL)-1β, IL-6, IL-8, tumor necrosis factor alpha (TNF-α), and myeloperoxidase, in sputum and peripheral blood of children with CF.

Secondary Objectives:

  1. To determine if glycine can improve respiratory symptoms, including decreased amount and better fluidity of sputum.
  2. To determine if glycine can improve spirometric variables.

Study design. This will be a randomized, placebo controlled, blinded, two-arms, cross-over clinical trial. Patients will receive glycine or placebo during the initial 8 weeks (initial phase), and after a 2 weeks washout period, they will receive the alternate treatment during another 8 weeks (second phase).

Material and methods: Children with CF fulfilling the selection criteria will be studied if their parents accept their participation. They will be randomly assigned to one of two groups. The experimental group will receive glycine and the control group will receive placebo (sugar glass), both at doses of 0.5 g/kg divided in 3 doses per os dissolved in any liquid. At study entry and at weeks 4, 8, 10, 14 and 18 we will collect a 2 ml blood sample and a sputum sample, and the children will be submitted to spirometry. A daily symptom questionnaire will be filled by the parents.

Statistical analysis: Each variable will be compared between experimental and control groups using Student's t test (or Mann Whitney U test if lacking normal distribution). Sample size: There are no previous studies that allow us to calculate a sample size. For convenience, it is estimated that 30 children can be included.

Time to complete: 24 months.

Interventional
Phase 2
Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Caregiver, Outcomes Assessor)
Primary Purpose: Treatment
Cystic Fibrosis
  • Dietary Supplement: Glycine
    Daily oral supplement of glycine at a dose of 0.5 g/kg divided in three doses during 8 weeks
    Other Name: aminoacetic acid
  • Dietary Supplement: Placebo
    Daily oral administration of placebo (sugar glass) at a dose of 0.5 g/kg divided in three doses during 8 weeks
    Other Name: sugar glass
  • Active Comparator: Glycine
    Patients will receive a daily oral supplement of 0.5 g/kg glycine dissolved in water.
    Intervention: Dietary Supplement: Glycine
  • Placebo Comparator: Placebo
    Patients will receive a daily supplement of 0.5 g/kg sugar glass dissolved in water.
    Intervention: Dietary Supplement: Placebo

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Terminated
13
September 2013
September 2013   (final data collection date for primary outcome measure)

Inclusion Criteria:

  • Children of either sex
  • Between 5 and 15 years of age
  • With CF diagnosed according to established criteria
  • Without changes in the CF treatment in the last 30 days
  • Without CF exacerbation in the last 30 days
  • Without acute respiratory infection (e.g., common cold) in the last 15 days
  • Informed consent letter signed by their parents or legal guardians

Exclusion Criteria:

  • Children with CF that had participated in a research protocol in the last 3 months
  • Presence of serious adverse effects attributable to glycine, in which case the result will be considered as therapeutic failure in the statistical analysis
  • Development of a CF exacerbation, in which case the available data so far collected will be included in the statistical analysis
Both
5 Years to 15 Years
No
Contact information is only displayed when the study is recruiting subjects
Mexico
 
NCT01417481
Glycine in CF
Yes
Mario H. Vargas, Instituto Nacional de Enfermedades Respiratorias
Instituto Nacional de Enfermedades Respiratorias
  • Hospital Infantil de Mexico Federico Gomez
  • Instituto Mexicano del Seguro Social
Principal Investigator: Mario H Vargas, MD, MSc Instituto Nacional de Enfermedades Respiratorias
Instituto Nacional de Enfermedades Respiratorias
October 2014

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP