Montelukast treatment for children with sickle cell disease

Study of Montelukast In ChiLdrEn With Sickle Cell Disease (SMILES)

Phase2; Phase3 Interventional Great Ormond Street Hospital for Children NHS Foundation Trust · NCT04351698

This study is testing if the asthma medication Montelukast can help young children with sickle cell disease and sleep problems think better and improve their brain function.

Quick facts

PhasePhase2; Phase3
Study typeInterventional
Enrollment200 (estimated)
Ages3 Years to 8 Years
SexAll
SponsorGreat Ormond Street Hospital for Children NHS Foundation Trust Academic / other
Locations1 site (London)
Trial IDNCT04351698 on ClinicalTrials.gov

What this trial studies

This trial investigates the effects of Montelukast, a medication commonly used for asthma, on young children with sickle cell disease who also experience sleep-disordered breathing. The study aims to determine if Montelukast can improve cognitive processing speed and overall brain function in these patients. A total of 200 participants aged 3 to 8 years will be recruited from various hospitals and will be randomly assigned to receive either Montelukast or a placebo for three months. Assessments will include brain speed tests and optional MRI scans before and after the treatment period.

Who should consider this trial

Good fit: Ideal candidates are children aged 3 to 8 years with sickle cell disease and a history of sleep-disordered breathing.

Not a fit: Patients with other neurodevelopmental disorders or those who have previously experienced adverse reactions to Montelukast may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could enhance cognitive function and quality of life for children with sickle cell disease.

How similar studies have performed: Previous studies have shown that Montelukast can improve symptoms of sleep-disordered breathing in other populations, suggesting potential for success in this novel application.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Aged between 3 and \<8 years
* Informed consent with assent in accordance with institutional policies and European guidelines; ICF (informed consent form) must be signed by patients/guardian
* HbSS 9homozygous SS disease) or HbSβ0 thalassaemia diagnosed by standard techniques (HPLC, IEF (Isoelectric focusing), MS (Mass spectrometry) or AlkE)
* History of Sleep-Disordered Breathing, (i.e. parent-reported any degree of snoring (CHSQ questionnaire) and/or any abnormality on overnight oximetry compared with published data in children of the same age (e.g. nadir SO2 (oxygen saturation) \<93%; mean SO2\<96%))
* Able to speak and understand English

Exclusion Criteria:

* Other neurodevelopmental disorders
* Patient already on Montelukast
* Patient has had side effects on or an adverse reaction to Montelukast in the past

Where this trial is running

London

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Anemia, Sickle CellSleep-Disordered Breathing
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.