Title of Project OCD in Children and Youth: Celecoxib versus Placebo as an Adjunct to Treatment-as-usual
Objective This study will investigate whether the addition of celecoxib will impact OCD severity in participants’ OCD severity.
Eligibility Criteria 1. Age 7-18 years

2. Resident of British Columbia

3. Diagnosis of moderate to severe OCD

4. Able to take medication twice daily in capsule form (in whole form or sprinkled contents)

5. Negative pregnancy test (either serum or urine) in participants with child-bearing potential

6. Use of highly effective and/or double barrier contraception, or abstinence, in participants with child-bearing potential

You are not eligible to apply if you meet the non-eligibility criteria below*

Potential Risks NSAIDs are well-tolerated in children at doses and durations exceeding those delivered in this trial, with the most common treatment-related adverse events including mild gastrointestinal symptoms that are mitigated by taking the medication with food. These include abdominal pain, nausea, diarrhea, and stomach upset.

Serious adverse events are very rare in children (<0.01%); these include gastrointestinal bleeding, ulcer, or perforation; kidney disease; and allergic reactions.

End date September 30, 2023
Study Involvement The initial survey will take about 30 to 40 minutes, and subsequent surveys can take between 15 to 20 mins.
Contact Interested participants can contact us at [email protected] and our research team will then arrange a phone call with you to provide more information about the study.


ACE-OCD is a clinical trial being run by Drs. Evelyn Stewart, a child and adolescent psychiatrist and professor at UBC, and Clara Westwell-Roper, a UBC Psychiatry Research Track Resident, at the Provincial OCD Program at BC Children’s Hospital Research Institute. Together they are investigating whether celecoxib, a non-steroidal anti-inflammatory drug often used for pain relief such as Advil, can help children and youth with Obsessive-Compulsive Disorder (OCD).

OCD is a condition that is characterised by unwanted upsetting thoughts or feelings (obsessions) that cause distress and anxiety and force individuals to perform actions or rituals they do not want to do (compulsions) to reduce the stress and anxiety caused by obsessions. OCD can interfere with daily activities, such as socializing, self-care, and school functioning. The usual treatments include cognitive behavioural therapy and medications called serotonin reuptake inhibitors, but almost half of children continue to experience symptoms despite these treatments.

Both genetic and environmental factors contribute to the development of OCD, but not all of these factors are understood. Research studies have suggested that proteins and cells related to inflammation may be affected in children and adults with OCD. Celecoxib belongs to a medication class called non-steroidal anti-inflammatory drugs (NSAIDS). A common NSAID that many children have taken previously is ibuprofen (Advil/Motrin), but it requires multiple doses per day to effectively reduce inflammation, whereas celecoxib is taken twice daily. NSAIDs such as celecoxib may limit inflammation and improve the function of neurons in parts of the brain involved in OCD symptoms.

This study will assess the effect of celecoxib on OCD symptom severity. Symptoms in participants receiving celecoxib (added to their usual treatment) will be compared to those receiving placebo, an inactive substance that looks identical to the test drug but contains no therapeutic or experimental ingredients. We expect that a total of 80 participants with OCD will be enrolled in this study, which is a single-site trial based at BCCH.

Health Canada, the regulatory body that oversees the use of natural health products/drugs/devices in Canada, has not approved the sale or use of celecoxib for OCD in either children or adults. Health Canada has allowed celecoxib to be used in this study.

The goal of this study is to determine whether 12 weeks of treatment with celecoxib added on to usual treatment results in improvement in OCD symptoms compared to placebo. This study is a randomized placebo-controlled trial, which means that half of participants will receive celecoxib and half will receive placebo, an identical capsule that does not contain the active drug. Participants may be assigned to either treatment. They will also continue their regular treatment (medication and/or psychotherapy) under the care of their regular doctor(s).

This is a Phase II study, which is undertaken after preliminary safety testing on a drug or treatment. Celecoxib has already been tested in previous studies for safety in children. Phase II studies are usually conducted on a small number of individuals. In this case, it will allow researchers to begin to find out what effect celecoxib has on OCD and to further evaluate its safety.


*Children and young adults are not eligible to participate in this study if any of the following apply:

  • They have been previously diagnosed with or develop conditions that would increase their risk of harm with NSAID use, including kidney or liver disease, gastrointestinal bleeding or peptic ulcer disease, inflammatory bowel disease, bleeding disorders, severe asthma, or NSAID allergy.
  • They have a current major depressive episode, psychosis, suicidality, or active substance use.
  • They have an active infection or are taking antibiotics.
  • They have used any NSAID at any dose more than 3 times per week in the 2 months prior to participation.
  • They currently take steroids (IV, oral, or inhaled) or drugs that may interact with celecoxib (detailed list included in Appendix A).
  • There is an abnormality identified on baseline blood work including liver enzymes, kidney function, and blood cell counts, or they have a form of an enzyme that metabolizes celecoxib that will significantly increase their levels.
  • Changes have been made to CBT or other psychotherapy in the 4 weeks prior to participation
  • They have started a new medication started in the 10 weeks prior to participation.
  • There are planned changes to their usual treatment during the study period.
  • They or their parents are unable to provide informed consent or assent, or to participate in study procedures or assessments in English.
  • They do not have a doctor (family physician or specialist) or other primary care provider (e.g. nurse practitioner) providing regular medical care.
  • Because there are risks associated with NSAID use in pregnancy, you should avoid becoming pregnant during this study. She should be aware of the risks to an unborn baby/fetus, and will be advised by study staff to work with her study doctor to find the best solution to make sure she does not get pregnant, if she wishes to be in the study.
  • They are unable to have blood pressure measured within 2 months prior to enrollment (either on-site at BCCH or by a primary care provider).
  • They have an intention of pregnancy.