A Study of Bitopertin (RO4917838) in Combination With Selective Serotonin Reuptake Inhibitors in Patients With Obsessive-Compulsive Disorder

Inclusion Criteria:

- Adult patients, 18 to 65 years of age

- Primary diagnosis of obsessive-compulsive disorder (OCD) as per Diagnostic and
Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR)

- On a stable dose of selective serotonin reuptake inhibitor (SSRI) for at least 8
weeks prior to screening an between screening and Day 1

- An insufficient response to current treatment with an SSRI given at an adequate dose
for at least 12 weeks prior to Day 1

- Females who are not postmenopausal or surgically sterile must agree to use two
adequate methods of contraception as defined by protocol from the start of screening
until 90 days after the last dose of study drug

Exclusion Criteria:

- Primary OCD symptom of hoarding

- More than two unsatisfactory trials within the last 2 years with different serotonin
reuptake inhibitors (not including the current treatment with an SSRI) given in an
adequate dose for at least 12 weeks

- Failure of more than one augmentation therapy or have had more than one augmentation
therapy used in conjunction with an SSRI

- Recently initiated (within the last 6 months) or current behavioral therapy
(cognitive behavioral therapy or exposure response prevention therapy)

- Any primary DSM-IV-TR Axis I disorder other than OCD

- Current or prior history of bipolar disorder, schizophrenia or other psychotic
disorders, schizoaffective disorder, autism or autistic spectrum disorders,
borderline personality disorder, or Gilles de la Tourette syndrome

- Any eating disorder within the last 6 months

- History od substance dependence and/or substance abuse in the last 6 months, with the
exception of nicotine

- Previous treatment with bitopertin or another GlyT-1 inhibitor

- Positive urine drug screening for cannabis, amphetamines (including MDMA/ecstasy),
cocaine, barbiturate, and/or opiates

- Prior or current general medical condition that may impair cognition or other
neuropsychiatric functioning

- Body mass index <18.5 kg/m2 or >40 kg/m2

- Pregnant or lactating women