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RecruitingNCT06560255FREYAUpdated Sep 30, 2025

Fish Oil in pREgnancY for Personalized Prevention of Early Childhood Asthma

A Phase 3 interventional study of n-3 fatty acid and Rape seed oil in Asthma, Respiratory Tract Infections and Gastrointestinal Infection, sponsored by Professor Klaus Bønnelykke. Recruiting at 1 site in Denmark. Open to female participants aged 18 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-09-30.

Sponsored by Professor Klaus Bønnelykke · Phase 3, Interventional, and Prevention

From the registry’s dates

  • Started Dec 2024; still recruiting 1 year 10 months later.
Phase
Phase 3
Study type
Interventional
Enrollment
2,000
Allocation
Randomized
Ages
18 Years to 45 Years
Sex
Female
01

Study summary

The overall aim of the study is to develop a nutritional preventive fish oil supplementation strategy in pregnancy for early childhood asthma/persistent wheeze during the first three years of life as we hypothesize that both supplementations in higher doses than recommended could reduce the risk of disease development.

Read the detailed description

Randomization of 2000 pregnant women to fish oil of 2.4 g/day (55% EPA and 37% DHA) in triacylglycerol form vs placebo. Supplementation begins in gestational week 24 (22-26) until 1 week after delivery. Allocation to the trial will be determined based on the pre-interventional maternal blood levels of EPA+DHA with a dried blood screening test. Women with low levels (below 4.7% of total fatty acids) will be assigned to the fish oil RCT. Maternal blood will be used for genetic, metabolomic and proteomic profiling. A 3-year follow-up of the children with longitudinal registration of parent reported symptoms, diagnoses, medication use, and hospitalizations will be performed. The primary outcome is persistent wheeze or asthma until age 3 years, with predefined analyses of effect modification by maternal genotypes. Secondary outcomes are lower respiratory tract infections, gastrointestinal infections, croup, troublesome lung symptoms, eczema, allergy, bone fractures, developmental milestones, mental health, cognition, and growth until age 3 years. A follow-up on both primary and secondary outcomes is planned after unblinding, from age 3 to 6 years.

02

Conditions studied

  • Asthma
  • Respiratory Tract Infections
  • Gastrointestinal Infection
  • Croup
  • Eczema
  • Allergy
  • Wheezing
  • Fractures, Bone
  • Development, Child
  • Cognition Disorders in Children
  • Psychiatric Diagnosis

Keywords

  • Childhood
  • Asthma
  • Infections
  • Eczema
  • Allergy
  • Development
  • Psychiatry
  • Bone development
  • Cognition
  • Growth
03

In context

Asthma

4,841 studies on the registry are indexed under Asthma; 600 are open to participants now.

This study's planned enrollment of 2,000 is above the median of 78 across 3,341 interventional studies indexed under Asthma.

Browse Asthma studies →

Lead sponsor

Professor Klaus Bønnelykke is the lead sponsor of 2 studies on the registry; 2 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 45 Years
Sexes eligible
Female
Accepts healthy volunteers
Yes

Eligibility criteria

  • Pregnant Danish women before week 26 with blood levels of EPA+DHA below 4.7% of total fatty acids
  • No planned use of fish oil supplementations
  • No endocrine-, heart-, kidney- or auto-immune disorders
  • No disorders requiring treatment with blood thinning medication
05

Study design

Phase
Phase 3
Primary purpose
Prevention
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment
2,000 participants (estimated)

Study arms

  • Experimental
    n-3 fatty acid of 2.4 g per day

    Oral intake of 4 capsules daily from week 22-26 of gestation until 1 week after delivery

    Dietary Supplement: n-3 fatty acid

  • Placebo comparator
    Rape seed oil

    Oral intake of 4 capsules daily from week 22-26 of gestation until 1 week after delivery

    Other: Rape seed oil

Interventions

  • Dietary supplementn-3 fatty acid

    Oral intake of 4 capsules per day from week 22-26 in pregnancy to 1 week after delivery

    Also known as: GoldenOmega, PharmaNord, DK

  • OtherRape seed oil

    Oral intake of 4 capsules per day from week 22-26 in pregnancy to 1 week after delivery

    Also known as: Placebo capsules, PharmaNord, DK

06

What researchers measure

Primary outcomes

  1. Early childhood asthma/persistent wheeze age 0-3 years

    Defined as either a) parental report of a minimum of 2 wheeze episodes with at least 1 after the child's second birthday and redemption of at least 2 prescriptions of asthma controller medication with at least 1 being after the child's second birthday or b) a minimum of 2 ED visits or hospitalizations due to asthmatic symptoms, and at least 1 of these being after the child's second birthday or c) parental report of physician-diagnosed asthma age 0-3 years Outcome analysis: risk (survival analysis) of persistent wheeze or asthma at age 0-3 years.

    Time frame: 3 years

Secondary outcomes

  1. Atopic/non-atopic wheeze or asthma age 0-3 years

    Parental reports of physician diagnosed asthma in combination with eczema and/or allergic rhinitis. Outcome analyses: asthma/persistent wheeze with/without eczema and/or allergic rhinitis (yes/no) by age 3 years. Each subtype is compared with children without asthma.

    Time frame: 3 years

  2. Troublesome lung symptoms age 0-3 years

    Defined as cough, wheeze or dyspnea severely affecting the well-being of the child for at least 3 consecutive days based on parental reports. Outcome analyses: total no. of episodes with symptoms age 0-3 years.

    Time frame: 3 years

  3. Wheeze episodes age 0-3 years

    Parental reports of wheezing. Outcome analyses: total no. of episodes with wheeze age 0-3 years.

    Time frame: 3 years

  4. Inhaled bronchodilator use from parental reports age 0-3 years

    Outcome analyses: total no. of days with bronchodilator use age 0-3.

    Time frame: 3 years

  5. Inhaled bronchodilator prescriptions from medical record checks age 0-3 years

    Outcome analyses: total no. of prescriptions age 0-3.

    Time frame: 3 years

  6. Asthma controller medication use from parental reports age 0-3 years

    Outcome analyses: total no. of days with use of asthma controller medication age 0-3.

    Time frame: 3 years

  7. Asthma controller medication prescriptions from medical record checks age 0-3 years

    Outcome analyses: total no. of prescriptions age 0-3.

    Time frame: 3 years

  8. Asthma hospitalizations or emergency department visits age 0-3 years

    Outcome analyses: total no. of episodes age 0-3 years.

    Time frame: 3 years

  9. Eczema age 0-3 years

    Parental reports of physician-diagnosed eczema and prescribed topical antiinflammatory medication on medical record checks. Outcome analyses: risk (survival analysis) of any eczema age 0-3 years and current eczema (yes/no) by age 3 years.

    Time frame: 3 years

  10. Allergic rhinitis age 0-3 years

    Based on parental reports of physician-diagnosed allergic rhinitis. Outcome analyses: allergic rhinitis (yes/no) by age 3 years.

    Time frame: 3 years

  11. Food allergy 0-3 years

    Parental reports of physician-diagnosed food allergy. Outcome analyses: any food allergy (yes/no) by age 3 years.

    Time frame: 3 years

  12. Lower respiratory tract infections age 0-3 years

    Parental reports of physician-diagnosed bronchiolitis or pneumonia. Outcome analysis: risk (survival analysis) of first lower respiratory tract infection and total no. of lower respiratory tract infections age 0-3 years.

    Time frame: 3 years

  13. Gastrointestinal infections age 0-3 years

    Parental reports. Outcome analyses: risk (survival analysis) of any gastroenteritis episode and total no. of gastroenteritis episodes age 0-3 years.

    Time frame: 3 years

  14. Croup age 0-3 years

    Parental reports of physician diagnosed croup. Outcome analysis: risk (survival analysis) of any croup episode and total no. of croup episodes age 0-3 years.

    Time frame: 3 years

  15. Fever episodes age 0-3 years

    Based on parental reports. Outcome analyses: total no. of episodes with symptoms age 0-3 years.

    Time frame: 3 years

  16. Absences from daycare age 0-3 years

    Due to illnesses based on parental reports. Outcome analyses: total no. of absence days age 0-3 years.

    Time frame: 3 years

  17. Bone fractures age 0-3 years

    Assessed by medical record checks including all radiologically verified fractures of larger long bones (i.e. clavicle, radius, ulna, tibia, fibula, femur and humerus). Outcome analyses: total no. of fractures age 0-3 years.

    Time frame: 3 years

  18. Developmental milestones age 0-3 years

    Monitored every 6 months until age 3 years by the parents using a registration form based on The Denver Development Index and WHO milestones registration. Outcome analyses: combined assessment of age at achievement across milestones by principal component analysis.

    Time frame: 3 years

  19. Strength and difficulties at age 3 years

    From the Strengths and Difficulties Questionnaire (SDQ), which is a brief behavioral screening questionnaire. Outcome analyses: SDQ scores at age 3 years.

    Time frame: 3 years

  20. ADHD symptoms at age 3 years

    From the ADHD rating scale-IV preschool, a dimensional questionnaire for ADHD symptoms in preschool children. Outcome analyses: ADHD symptom scores at age 3 years.

    Time frame: 3 years

  21. Social behavior assessment at age 3 years

    From the Social Responsiveness Scale, Second Edition; a questionnaire for screening for autistic traits: Outcome analyses: Total problem scores at age 3 years.

    Time frame: 3 years

  22. Psychopathology screening at age 3 years

    From the Child Behavior Check List 1,5-5 years; a questionnaire for general screening of preschool psychopathology. Outcome analyses: Total syndrome scales at age 3 years.

    Time frame: 3 years

  23. Cognitive assessment age 0-3 years

    From Behavior Rating Inventory of Executive Function in preschool children; a measurement of executive functions. Outcome analyses: Index values at age 3 years.

    Time frame: 3 years

  24. BMI and waist circumference age 0-3 years

    From parental reports every 6 months. Outcome analyses: development of BMI and waist circumference age 0-3 years and current BMI and waist circumference at age 3.

    Time frame: 3 years

  25. Persistent wheeze or asthma age 0-6 years

    Defined similarly to the primary outcome Outcome analysis: risk (survival analysis) of persistent wheeze or asthma at age 0-6 years

    Time frame: 6 years

  26. Current asthma at age 6 years

    Defined similarly to the primary outcome and with symptoms and/or asthma medication use in the last 12 months at age 6. Outcome analyses: Current wheeze or asthma (yes/no) by age 6 years.

    Time frame: 6 years

  27. Asthma or wheeze yearly prevalence 0-6 years

    Defined as in the primary outcome and current disease defined from parental reports of wheeze and/or asthma medication use. Outcome analyses: Yearly prevalence of wheeze or asthma medication use (yes/no) 0-6 years.

    Time frame: 6 years

  28. Atopic/non-atopic asthma at age 6 years

    Parental reports of physician diagnosed asthma in combination with eczema and/or allergic rhinitis. Outcome analyses: Current asthma with/without eczema and/or allergic rhinitis (yes/no) by age 6 years. Each subtype is compared with children without asthma.

    Time frame: 6 years

  29. Asthma controller medication 0-6 years

    From redeemed medication prescriptions (inhaled corticosteroids and leukotriene modifiers) based on medical record checks: Outcome analyses: total no. of prescriptions age 0-6 years.

    Time frame: 6 years

  30. Inhaled bronchodilators age 0-6 years

    From redeemed inhaled bronchodilators based on medical record checks. Outcome analyses: total no. of prescriptions age 0-6 years.

    Time frame: 6 years

  31. Asthma hospitalizations or emergency department visits age 0-6 years

    Based on medical record checks. Outcome analyses: total no. of episodes age 0-6 years.

    Time frame: 6 years

  32. Eczema age 0-6 years

    Based on parental reports of physician diagnosed eczema. Outcome analyses: risk (survival analysis) of any eczema age 0-6 years and current eczema (yes/no) by age 6 years.

    Time frame: 6 years

  33. Allergic rhinitis age 0-6 years

    Based on parental reports of physician-diagnosed allergic rhinitis and on medical record checks. Outcome analyses: allergic rhinitis (yes/no) by age 6 years.

    Time frame: 6 years

  34. Food allergy age 0-6 years

    Based on parental reports of physician-diagnosed food allergy. Outcome analyses: any food allergy (yes/no) by age 6 years.

    Time frame: 6 years

  35. Lower respiratory tract infections age 0-6 years

    Based on parental reports of physician-diagnosed bronchiolitis or pneumonia. Outcome analysis: risk (survival analysis) of first lower respiratory tract infection and total no. of lower respiratory tract infections age 0-6 years.

    Time frame: 6 years

  36. Gastrointestinal infections age 0-6 years

    Based on parental reports. Outcome analyses: risk (survival analysis) of any gastroenteritis episode and total no. of gastroenteritis episodes age 0-6 years.

    Time frame: 6 years

  37. Croup age 0-6 years

    Based on parental reports of physician diagnosed croup. Outcome analysis: risk (survival analysis) of any croup episode and total no. of croup episodes age 0-6 years.

    Time frame: 6 years

  38. Bone fractures age 0-6 years

    Assessed by medical record checks including all radiologically verified fractures of larger long bones (i.e. clavicle, radius, ulna, tibia, fibula, femur and humerus). Outcome analyses: total no. of fractures age 0-6 years.

    Time frame: 6 years

  39. Strength and difficulties at age 6 years

    From the Strengths and Difficulties Questionnaire (SDQ), which is a brief behavioral screening questionnaire. Outcome analyses: SDQ scores at age 6 years.

    Time frame: 6 years

  40. ADHD symptoms at age 6 years

    From the ADHD rating scale-IV preschool, a dimensional questionnaire for ADHD symptoms in preschool children. Outcome analyses: ADHD symptom scores at age 6 years.

    Time frame: 6 years

  41. Social behavior assessment at age 6 years

    From the Social Responsiveness Scale, Second Edition; a questionnaire for screening for autistic traits. Outcome analyses: Total problem scores at age 6 years.

    Time frame: 6 years

  42. Psychopathology screening at age 6 years

    From the Child Behavior Check List; a questionnaire for general screening of preschool psychopathology. Outcome analyses: Total syndrome scales at age 6 years.

    Time frame: 6 years

  43. Cognitive assessment age 0-6 years

    From Behavior Rating Inventory of Executive Function in preschool children; a measurement of executive functions. Outcome analyses: Index values at age 6 years.

    Time frame: 6 years

  44. BMI and waist circumference age 0-6 years

    From parental reports every 6 months. Outcome analyses: development of BMI and waist circumference age 0-6 years and current BMI and waist circumference at age 6.

    Time frame: 6 years

07

Study locations

1 of 1 sites recruiting
  • Copenhagen University Hospital of Copenhagen
    Gentofte Municipality, DK-2820, Denmark
    Recruiting
    • Klaus Bønnelykke, PhD · Contactkb@copsac.com · +45 38677360
    • Ulrik Ralfkiaer, PhD · Contactulrik.ralfkiaer@dbac.dk · +45 38674164
    • Klaus Bønnelykke, PhD · Principal investigator
    • Bo Chawes, PhD · Principal investigator
08

References and documents

Publications

  • Brustad N, Vahman N, Ralfkiaer U, Mikkelsen M, Brandt S, Kyvsgaard JN, Vinding R, Stokholm J, Chawes B, Bonnelykke K. Fish oil and vitamin D in pregnancy for the prevention of early childhood asthma: study protocol for two double-blinded, randomised controlled trials. BMJ Open. 2024 Dec 31;14(12):e092902. doi: 10.1136/bmjopen-2024-092902. PubMed 39740942 ↗

Individual participant data

Plan to share: No

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Sep 30, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT06560255
Lead sponsor
Professor Klaus Bønnelykke
Responsible party
Professor Klaus Bønnelykke (Professor PhD, Head of COPSAC, Copenhagen Studies on Asthma in Childhood) — Sponsor-investigator
First posted
Aug 19, 2024
Start date
Dec 20, 2024
Primary completion
Oct 2026 (estimated)
Completion
Mar 2033 (estimated)
Last update
Sep 30, 2025

Study contacts

Klaus Bønnelykke, PhD
Contact
kb@copsac.com
+45 38677360
Ulrik Ralfkiaer, PhD
Contact
administration@dbac.dk
+45 38674164
Bo Chawes, PhD
principal investigator · Copenhagen Studies on Asthma in Childhood
Klaus Bønnelykke, PhD
principal investigator · Copenhagen Studies on Asthma in Childhood

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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