Omega-3 Fatty Acids as Adjunct Treatment for Major Depressive Disorder
Evaluation of Omega-3 Fatty Acids as a Treatment-adjunct in Adolescent Patients With Major Depressive Disorder Exhibiting Partial Response to SSRI Medications: An Open-label Neuroimaging Trial
  • Phase

    Phase 2/Phase 3
  • Study Type

  • Intervention/Treatment

    fish oil ...
  • Study Participants

The primary objective of the study was to determine the effects of 10-week adjunctive supplementation with 2 doses of LCn-3 fatty acids (fish oil) on cortical functional activity and biochemistry in adolescents with MDD.

The primary prediction was that LCn-3 fatty acid supplementation would dose-dependently increase prefrontal cortical functional activation during sustained attention and increase regional biochemical indices of cortical metabolism and integrity concentrations in association with reductions in depressive symptoms.
This study is a 10-week open-label EPA+DHA treatment trial in adolescent (aged 12-18 years) patients with major depressive disorder exhibiting partial response to SSRI medications. After a screening visit, patients were randomized (stratified by gender) to open-label fish oil supplements at a fixed dose of either 2.4 g/day or 15 g/day (2 tablespoons/day) for 10 weeks.

A physical examination, a complete blood count (CBC), and thyroid stimulating hormone (TSH) levels were determined at baseline and Week 10, and vital signs (pulse, blood pressure, weight, height, body mass index, temperature) were obtained at each visit. At each visit, safety and tolerability were assessed using a structured side effect interview, the Side Effects Form for Children and Adolescents.

At baseline and all weekly visits, depression symptom severity was determined with the Children's Depression Rating Scale-Revised (CDRS-R), a 17-item observer-rated questionnaire, and remission was defined as a CDRS-R score of ≥28. If a patient's depressive symptoms worsened over the course of the trial (defined as 30% worsening relative to baseline on two consecutive visits using CDRS-R scores), they were withdrawn from the study. In view of the potential risk for developing hypomanic symptoms following LCn-3 fatty acid supplementation, manic symptom severity was monitored over the course of the trial with the Young Mania Rating Scale (YMRS), an 11-item observer-rated questionnaire.

fMRI scans were performed at baseline and at 10 weeks.
Study Started
Aug 31
Primary Completion
Mar 31
Study Completion
Mar 31
Results Posted
Dec 04
Last Update
May 27

Drug Low Dose Fish Oil

Omega-3 Fatty Acids 2.4g/day in capsule form (4 capsules per day)

  • Other names: OmegaRx - Zone Laboratories

Drug High Dose Fish Oil

Liquid omega-3 fatty acid 15 g/day (2 tablespoons/day)

  • Other names: OmegaRx - Zone Laboratories

Low Dose Fish Oil Experimental

Capsule omega-3 fatty acids 2.4g/day (4 capsules/day)

High Dose Fish Oil Experimental

Liquid omega-3 fatty acid 15 g/day (2 tablespoons/day)


Inclusion Criterion:

Between the ages of 12-18 years.
Diagnosis of MDD and not exhibited symptom remission CDRS-R (> 28 but < 40) despite being administered a standard therapeutic dose of an SSRI continuously for a minimum of 6 weeks.
Ability and willingness to provide assent and informed, written consent from at least one biological parent.
Present with biological parent or legal guardian.
Willingness to maintain current dietary habits.
Permission from treating physician
Able to perform fMRI/MRS.

Exclusion Criterion:

Inability or unwillingness to provide consent.
Antecedent or concurrent serious medical illness.
Clinically unstable medical disease, including cardiovascular, hepatic insufficiency, severe renal impairment, gastrointestinal, pulmonary, metabolic, endocrine, obesity or other systemic disease.
History of seizures, excluding febrile seizures in childhood.
Patients requiring treatment with any drug which might obscure the action of the study treatment.
Female patients who are either pregnant or lactating.
Clinically significant laboratory abnormalities in the last year on CBC or TSH tests.
Judged clinically to be at suicidal risk (defined as having active suicidal ideation, intent or plan, or a serious suicide attempt within the past 6 months, or a baseline CDRS-R suicide score of >3).
Hospitalized within the last 3 months
Greater than 1 year outside appropriate age/grade level
Cerebral aneurysm clip
Cochlear implant
Metal fragments lodged within the eye or braces
Necessity of sedation (no sedation will be given).
History of loss of consciousness > 10 minutes in duration
Allergy to seafood.


High Dose Fish Oil

Low Dose Fish Oil

All Events

Event Type Organ System Event Term High Dose Fish Oil Low Dose Fish Oil

Mood Symptoms Ratings

Depression symptom severity was determined with the Children's Depression Rating Scale-Revised (CDRS-R), which is a brief rating scale based on a semi-structured interview with the child. It is a 17-item observer-rated questionnaire where the 17 symptom areas are rated on a 6- or 7-point scale. Total score ranges from a low (not depressed) of 17 to a maximum (very depressed) of 108. Remission was defined as a CDRS-R score of <28. (The total score is the sum of the ratings on each of the 17 items.)

Baseline CDRS-R: High Dose Fish Oil

CDRS-R score (Mean)
Standard Deviation: 1.5

Baseline CDRS-R: Low Dose Fish Oil

CDRS-R score (Mean)
Standard Deviation: 1.7





Age, Continuous

years (Mean)
Standard Deviation: 3.05

Depression Score

CDRS-R Score (Mean)
Standard Deviation: 4.8

Age, Categorical

Region of Enrollment

Sex: Female, Male

Overall Study

High Dose Fish Oil

Low Dose Fish Oil

Drop/Withdrawal Reasons

High Dose Fish Oil

Low Dose Fish Oil