Conditions: Obsessive-compulsive Disorder
Keywords: Obsessive-compulsive disorder
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 30
Healthy volunteers: yes

Brief summary:
Cognitive-behavioral therapy (CBT) has proven efficacy for treatment of pediatric obsessive-compulsive disorder (OCD). Yet, CBT does not help all children and those who benefit often remain symptomatic upon treatment completion. Recent clinical trials in adults with other anxiety disorders (acrophobia and social phobia) provided support for using a medication called D-Cycloserine (DCS) to enahnce the outcome of exposure-based psychotherapy. Given this, DCS may augment CBT in youth with OCD, an anxiety disorder that is conceptually similar to acrophobia. With this in mind, the investigators are conducting a randomized, double-blind placebo controlled pilot study of DCS to determine whether it had any short-term clinical benefits on CBT in youth with OCD. Forty children and adolescents (ages 8-17) with a primary diagnosis of OCD will be screened and, should they meet relevant criteria, randomly assigned to one of two treatment conditions: (1) CBT plus DCS, or (2) CBT plus placebo. All patients will receive 10 sessions of CBT A rater will assess participants at 3 separate time points.

Detailed description:
Cognitive-behavioral therapy (CBT) has proven efficacy for treatment of pediatric obsessive-compulsive disorder (OCD). Yet, CBT does not help all children and those who benefit often remain symptomatic upon treatment completion. The behavioral theory that underlies CBT is based on two components, namely fear conditioning and extinction. On a neural level, CBT incorporates similar mechanisms to those involved in fear conditioning. Antagonists at the N-methyl-D-aspartate (NMDA) glutamatergic receptor, which is involved in learning and memory, block both fear learning and extinction. Evidence suggests that D-Cycloserine (DCS), a partial agonist at the NMDA glutamate receptor, augments associative learning and extinction as a form of learning in animals and humans. Recent clinical trials in adults with other anxiety disorders (acrophobia and social phobia) provided support for DCS dosing as facilitating associative learning that occurs during exposure-based psychotherapy. Given that CBT is based on the principles of extinction, DCS may augment CBT in youth with OCD, an anxiety disorder that is conceptually similar to acrophobia. With this in mind, I propose to undertake a randomized, double-blind placebo controlled pilot study of DCS to determine whether it had any short-term clinical benefits on CBT in youth with OCD. Forty children and adolescents (ages 8-17) with a primary diagnosis of OCD will be screened and, should they meet relevant criteria, randomly assigned to one of two treatment conditions: (1) CBT plus DCS (25 or 50mg depending on weight), or (2) CBT plus placebo. All patients will receive 10 sessions of CBT based on the protocol used in POTS (2004). Participants will take DCS or placebo 1 hour prior to each therapy session. A blinded, independent evaluator will assess participants at 3 separate time points. Two of the assessments (Baseline, Post-treatment) will be comprehensive in nature (e.g., diagnostic interview, self-reports, CY-BOCS, laboratory tests), whereas one midpoint assessment will involve administration of CY-BOCS, CGI, CGI-S, and Adverse Symptom Checklist only. Results from this study may have powerful clinical implications by providing preliminary support for pharmalogical agents that enhance the effectiveness of standard E/RP. Such agents may have utility in improving outcome, reducing premature therapy termination, and targeting patients who have been treatment refractory.

Arms:
arm 1: Involves receiving cognitive-behavioral treatment of OCD symptoms for 10 sessions. One hour prior to sessions 4-10, the child will take either 1 or 2 pills containing 25mg of placebo. The number of pills depends on the child's weight (e.g., about 46kgs takes 2 capsules). arm 2: Involves receiving cognitive-behavioral treatment of OCD symptoms for 10 sessions. One hour prior to sessions 4-10, the child will take either 1 or 2 pills containing 25mg of D-cycloserine. The number of pills depends on the child's weight (e.g., about 46kgs takes 2 capsules).

Interventions: intervention 1: Cognitive-behavioral therapy intervention 2: D-cycloserine intervention 3: Placebo pill
Intervention descriptions: intervention 1: All patients will receive 10 sessions of therapy over 8 weeks that is based on the protocol used in POTS (2004). Sessions 1-4 will be held twice weekly; thereafter sessions will be held on a weekly basis. This evidence-based E/RP intervention (POTS, 2004) includes psychoeducation, cognitive training, and exposure and response prevention. By design, this manual provides sufficient flexibility to accommodate the child's developmental needs and address maladaptive parent-child interactions (e.g., accommodation). intervention 2: D-cycloserine (Seromycin, 250 mg; Eli Lilly and Co, Indianapolis, Indiana) will be capsulated into 25mg with identical placebo capsules. Children weighing between 25-45kg will be given a dosage of 25mg (approximately 0.56-1.0 mg/kg/day). Children weighing between 46-80kg will be given a dosage of 50mg (approximately 0.63-1.08mg/kg/day). DCS or placebo will be given by parents 1 hour prior to psychotherapy sessions (before sessions 4-10 only) based on past success in patients with acrophobia (Ressler et al., 2004) and DCS absorption rates. intervention 3: This intervention involves taking a placebo pill(s) that matches the d-cycloserine capsules in size, shape, weight, and taste. Placebo contains an no active medication.

Protocol document: