D-cycloserine Augmented Treatment for Youth With Tic Disorders

D-cycloserine Augmented Treatment: Enhancing Extinction Learning in Youth With Tic Disorders

This pilot study aims evaluate the feasibility and initial efficacy of behavior therapy augmented by d-cycloserine (DCS) compared to behavior therapy augmented by placebo. After an initial assessment to determine eligibility, youth with TD will be randomly assigned to receive four sessions of behavior therapy augmented by either DCS or placebo. D-cycloserine is an FDA-approved antibiotic medication that has been shown to enhance extinction learning in several studies. The investigators' proof-of-concept work has found that a single session of DCS-augmented behavior therapy reduced the severity of tics targeted in treatment on the Hopkins Motor/Vocal Tic Scale (HM/VTS) compared to placebo-augmented behavior therapy. This highlights the exciting potential of combining DCS with behavior therapy to improve reductions in tic severity. However, prior to a large-scale clinical trial, it is essential to determine the feasibility and efficacy of augmenting behavior therapy with DCS over multiple treatment sessions.

Tourette's Disorder and Persistent Tic Disorders (collectively referred to as TD) are characterized by the presence of motor and/or vocal tics. For many youth with TD, the severity of tics results in considerable functional impairment and a poor quality of life. While historically managed with psychotropic medications, behavior therapy has demonstrated efficacy for reducing the severity of tics. However, only 50% of youth with TD exhibit a positive treatment response to behavior therapy, and many treatment responders continue to experience bothersome tics. Thus, there is a need to investigate strategies to improve therapeutic outcomes from behavior therapy for youth with TD.

This pilot study aims evaluate the feasibility and initial efficacy of behavior therapy augmented by d-cycloserine (DCS) compared to behavior therapy augmented by placebo. After an initial assessment to determine eligibility, youth with TD will be randomly assigned to receive four sessions of behavior therapy augmented by either DCS or placebo. D-cycloserine is an FDA-approved antibiotic medication that has been shown to enhance extinction learning in several studies. The investigators' proof-of-concept work has found that a single session of DCS-augmented behavior therapy reduced the severity of tics targeted in treatment on the Hopkins Motor/Vocal Tic Scale (HM/VTS) compared to placebo-augmented behavior therapy. This highlights the exciting potential of combining DCS with behavior therapy to improve reductions in tic severity. However, prior to a large-scale clinical trial, it is essential to determine the feasibility and efficacy of augmenting behavior therapy with DCS over multiple treatment sessions.

Inclusion Criteria:

• 8-17 years
• Meet Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 criteria for Tourette's Disorder, Persistent Motor Tic Disorder, or Persistent Vocal Tic Disorder
• Have moderate tic severity or greater as evidenced by a Yale Global Tic Severity Scale (YGTSS) total score greater than 13 (>9 for children with motor or vocal tics only)
• Be fluent in English

Exclusion Criteria:

• Current diagnosis of substance abuse/dependence
• Lifetime diagnosis of autism spectrum disorder, mania or psychosis
• History of a seizure disorder, kidney disease, or liver disease
• Four or more previous sessions of behavior therapy