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L-Citrulline for Asthma (SEALS Trial)

Phase 2
Recruiting
Led By Fernando Holguin, MD, MPH
Research Sponsored by University of Colorado, Denver
Eligibility Criteria Checklist
Specific guidelines that determine who can or cannot participate in a clinical trial
Must have
Suboptimal asthma control at baseline (ACQ ≥ 0.5 or ACT<19)
Smoking tobacco history ≤15 pack years and no smoking in the last 3 months
Must not have
Chronic renal failure (creatinine > 2.0) at Visit 0 (Associated with higher ADMA levels)
Concomitant use of PDE5 drugs or oral mononitrates
Timeline
Screening 3 weeks
Treatment Varies
Follow Up through study completion, up to 22 weeks

Summary

This trial aims to help service members with asthma that doesn't respond to usual treatments by using L-citrulline. L-citrulline can boost substances in the body that help keep airways open, potentially improving breathing and asthma symptoms. The goal is to find a safe and affordable treatment to enhance the quality of life for these patients.

Who is the study for?
This trial is for military personnel aged 18-70 who developed asthma after deployment post-9/11. Participants must have a history of smoking less than or equal to 15 pack years, no recent smoking, and show signs of suboptimal asthma control. Pregnant individuals, those on recent corticosteroids or with significant illnesses like heart disease or uncontrolled diabetes are excluded.
What is being tested?
The study tests if L-citrulline supplementation can improve lung function in patients with deployment-related asthma by increasing airway nitric oxide levels. It's compared against a placebo in a controlled setting to see if it offers an effective add-on therapy for better asthma management.
What are the potential side effects?
Potential side effects may include intolerance reactions similar to allergies due to L-citrulline or digestive issues since it's an amino acid supplement. However, the exact side effects will be monitored as part of the study.

Eligibility Criteria

Inclusion Criteria

You may be eligible if you check “Yes” for the criteria below
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My asthma is not well-controlled.
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I have smoked 15 or fewer pack-years and haven't smoked in the last 3 months.
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I am between 18 and 70 years old.
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I have asthma symptoms that started after military service in Southwest Asia post-9/11.

Exclusion Criteria

You may be eligible for the trial if you check “No” for criteria below:
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My kidney function is impaired with high creatinine levels.
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I am currently taking medication for erectile dysfunction or heart conditions.

Timeline

Screening ~ 3 weeks
Treatment ~ Varies
Follow Up ~through study completion, up to 22 weeks
This trial's timeline: 3 weeks for screening, Varies for treatment, and through study completion, up to 22 weeks for reporting.

Treatment Details

Study Objectives

Study objectives can provide a clearer picture of what you can expect from a treatment.
Primary study objectives
Change in Asthma Control Questionnaire
Apo-Feno-Micro

Side effects data

From 2019 Phase 3 trial • 189 Patients • NCT02891837
18%
Pyrexia
14%
Pain
13%
Hypertension
12%
Tachycardia
12%
Hypokalaemia
11%
Constipation
11%
Restlessness
8%
Haemoglobin decreased
8%
Pleural effusion
7%
Hypocalcaemia
7%
Tachypnoea
5%
Vomiting
5%
Electrolyte imbalance
5%
Cough
5%
Pulmonary congestion
5%
Hypotension
4%
Metabolic acidosis
4%
Hypomagnesaemia
4%
Stridor
4%
Oligurea
4%
Atelectasis
4%
Leukocytosis
3%
Anaemia
3%
Sinus bradycardia
3%
Diarrhoea
3%
Post procedural haemorrhage
3%
Blood pressure decreased
3%
Coagulation time prolonged
3%
Pulmonary oedema
3%
Haematocrit decreased
1%
Ventricular tachycardia
1%
Arrhythmia
1%
Staphylococcal infection
1%
Cardiac tamponade
1%
Ventricular fibrillation
1%
Leukopenia
1%
Thrombocytopenia
1%
Aortic valve incompetence
1%
Atrioventricular block complete
1%
Nausea
1%
Peripheral swelling
1%
Blood lactic acid increased
1%
C-reactive protein increased
1%
Chylothorax
100%
80%
60%
40%
20%
0%
Study treatment Arm
L-citrulline - All Patients on Mechanical Ventilation for ≤48 Hours
L-citrulline - All Patients
L-citrulline - US Patients on Mechanical Ventilation for >48 Hours
Placebo - All Patients
L-citrulline - US Patients on Mechanical Ventilation for ≤48 Hours
L-citrulline - All Patients on Mechanical Ventilation for >48 Hours
Placebo - All Patients on Mechanical Ventilation for ≤48 Hours
Placebo - US Patients on Mechanical Ventilation for ≤48 Hours
Placebo - All Patients on Mechanical Ventilation for >48 Hours
Placebo - US Patients on Mechanical Ventilation for >48 Hours

Trial Design

2Treatment groups
Experimental Treatment
Placebo Group
Group I: L-citrullineExperimental Treatment1 Intervention
L-citrulline with a dose of 15 g/day will be administered in powder form that is mixed with water and taken orally, continuously and daily for at least 7 weeks. Dispensed at Visits 0a/1. Washout period of 4 to 6 weeks and then enter crossover phase of an additional 7 weeks. Drug will be dispensed at Visit 4.
Group II: Matching PlaceboPlacebo Group1 Intervention
Administered in powder form that is mixed with water and taken orally, continuously, and daily for at least 7 weeks. Dispensed at Visits 0a/. Washout period of 4 to 6 weeks and then enter crossover phase of an additional 7 weeks. Drug will be dispensed at Visit 4.
Treatment
First Studied
Drug Approval Stage
How many patients have taken this drug
L-citrulline
2010
Completed Phase 3
~530

Research Highlights

Information in this section is not a recommendation. We encourage patients to speak with their healthcare team when evaluating any treatment decision.
Mechanism Of Action
Side Effect Profile
Prior Approvals
Other Research
Common treatments for asthma include bronchodilators, corticosteroids, and leukotriene modifiers. Bronchodilators, such as beta-agonists, work by relaxing the muscles around the airways, making it easier to breathe. Corticosteroids reduce inflammation in the airways, preventing asthma attacks. Leukotriene modifiers block chemicals that cause inflammation and bronchoconstriction. L-citrulline, an emerging treatment, increases levels of L-arginine and FeNO, which helps to keep airways open and reduce oxidative stress. These mechanisms are crucial for asthma patients as they improve lung function, reduce symptoms, and prevent exacerbations, thereby enhancing overall quality of life.
Managing Asthma in Pregnancy (MAP) trial: FENO levels and childhood asthma.

Find a Location

Who is running the clinical trial?

National Jewish HealthOTHER
143 Previous Clinical Trials
317,125 Total Patients Enrolled
24 Trials studying Asthma
18,784 Patients Enrolled for Asthma
University of Colorado, DenverLead Sponsor
1,802 Previous Clinical Trials
2,822,037 Total Patients Enrolled
20 Trials studying Asthma
2,910 Patients Enrolled for Asthma
United States Department of DefenseFED
908 Previous Clinical Trials
333,605 Total Patients Enrolled

Media Library

L-citrulline Clinical Trial Eligibility Overview. Trial Name: NCT05259904 — Phase 2
Asthma Research Study Groups: L-citrulline, Matching Placebo
Asthma Clinical Trial 2023: L-citrulline Highlights & Side Effects. Trial Name: NCT05259904 — Phase 2
L-citrulline 2023 Treatment Timeline for Medical Study. Trial Name: NCT05259904 — Phase 2
~50 spots leftby Oct 2028