Obsessive-compulsive disorder (OCD) is a common psychiatric illness that affects up to 2-3% of the population. People with OCD experience anxiety-provoking, intrusive thoughts, known as obsessions, and feel compelled to perform repetitive behaviors, or compulsions. The only medications proven effective for OCD are serotonin reuptake inhibitors (SRIs), but even with SRI treatment, most patients continue to experience significant OCD symptoms, impaired functioning, and diminished quality of life. Recent evidence suggest that a different neurotransmitter, glutamate, may contribute to the symptoms in OCD. Medications that target glutamate hold promise for ameliorating symptoms for those patients continuing to suffer from OCD. In this study we are recruiting patients to receive the drug NPL-2003, which is thought to modulate the neurotransmitter glutamate, added to whatever other OCD medications they are taking in a 12-week open label study.

Inclusion Criteria:

• Primary DSM-IV Diagnosis of OCD
• Currently on a stable and adequate dose of SRI (or history of prior SRI or CBT treatment meeting criteria for adequate trial)
• Patients not currently receiving an SRI or CBT will be included if they have undergone a prior SRI or CBT trial and they report no interest in pursuing another DRI or CBT trial at this time. Patients who have been on SRIs in the past must be free of SRIs for at least 6 weeks prior to participation
• Y-BOCS score of greater or equal to 16
• Physically health and females must be using effective contraception
• Sufficient severity of symptoms to warrant additional augmentation treatment
• Able to provide consent

Exclusion Criteria:

• Ongoing treatment with other antibiotics and/or Accutane. Patients with lupus erythematosus
• Patients planning to start CBT during the study period or those who have begun CBT within the past 8 weeks
• Presence of psychotic symptoms or lifetime history of schizophrenia, bipolar disorder or other psychotic disorder
• Current major depressive disorder (patients must be free of the disorder for 3 months prior to enrollment). HAM-D must be <18.
• Judged clinically to be at risk of suicide (suicidal ideation, severe depression or other factors
• Current eating disorder
• Severe renal insufficiency
• Documented history of hypersensitivity or intolerance to tetracycline antibiotics
• Concomitant use of anti-coagulant drugs, antacids, iron, calcium, magnesium, aluminum, zinc sales. Note:Concomitant psychotropic medications such as antipsychotics and benzodiazepines will be permitted as long as they have been stable for at least 4 weeks and remain stable during the course of the study.
• Current ETOH/drug abuse or dependence disorder of dependency in the past 3 months
• Female patients who are either pregnant or nursing

12 weeks