Clinical trial NCT02911324
Conditions: Obsessive-Compulsive Disorder
Sponsor: New York State Psychiatric Institute
Start date: 2016-09-01; Completion date: 2019-01-01
Enrollment: 16 participants; Allocation: RANDOMIZED; Intervention model: PARALLEL

Brief summary:
The purpose of this pilot research study is to test the effects of a medication called nabilone (Cesamet) in adults with obsessive-compulsive disorder (OCD). Participants will receive either nabilone on its own, or nabilone in combination with a form of cognitive-behavioral therapy (CBT) called exposure and response prevention (EX/RP). Nabilone is a synthetic cannabinoid and acts on the brain's "endocannabinoid system," which has been hypothesized to play a role in OCD. Nabilone is approved by the FDA for the treatment of chemotherapy-induced nausea and vomiting. It is not FDA-approved for treating OCD.

Detailed description:
The two first-line treatments for OCD are a class of medications called serotonin reuptake inhibitors (SRIs) and a type of cognitive behavioral therapy called exposure and response prevention (EX/RP). But more than a third of patients with OCD do not respond to these treatments, and less then half become well. Thus, new treatment approaches are needed.

EX/RP is thought to involve fear extinction learning. Recent research suggests that modulators of the endocannabinoid system such as nabilone (a synthetic cannabinoid and agonist of the cannabinoid 1 receptor, CB1R) may enhance fear extinction learning and therefor could enhance EX/RP. However, nabilone could also work via modulating activity in cortico-striatal circuits, which contain high concentrations of CB1R, and thereby might reduce repetitive behaviors like compulsions seen in OCD.

To test both ideas, we will conduct a small pilot randomized trial to explore the effects of nabilone on its own for 4 weeks, vs. combined with EX/RP, in adult patients with OCD. This proof-of-concept study will investigate whether nabilone administration is feasible and well-tolerated in adult patients with OCD. The intent is to collect pilot data to support future grant applications.

Arms: arm 1: Will receive nabilone at 1 mg daily (BID) over 4 weeks. arm 2: Will receive nabilone at 1 mg daily (BID) plus therapist-guided Exposure and Response Prevention Therapy during 4 weeks.
Interventions: intervention 1: Nabilone intervention 2: Exposure and Response Prevention Therapy
Intervention descriptions: intervention 1: Nabilone is a synthetic cannabinoid that is thought to be a Cannabinoid receptor type 1 (CB 1) agonist. It acts on the brain's "endocannabinoid system," which has been hypothesized to play a role in OCD. intervention 2: Exposure and Response Prevention Therapy (EX/RP) is a type of Cognitive-Behavioral Therapy for OCD that involves intentionally confronting situations that trigger obsessional distress while refraining from doing compulsions.

Protocol documents:
Prot_ICF_000.pdf: 
 
Cannabinoid Medication for Adults with OCD 
NCT02911324 
1/7/2020 
 


























IRB#7239 (4/09/18) 
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CONSENT FORM- COVER SHEET 
CANNABINOID MEDICATION FOR ADULTS WITH OCD 
Overview 
Below is a summary of the study that you are asked to participate in. This outline is meant to be a guide for you to use 
while considering the study and reading the consent form. It is not meant to replace the consent form, which you will have 
to sign if you decide to participate in the study. The consent form contains detailed information about the study and about 
the risks which you will need to consider before making your decision. Read the consent form carefully and discuss it 
with others before deciding to take part. And remember that, even if you do agree to participate, you can change your 
mind at any time.  
Participation is Voluntary
As with all research, this is a voluntary study, and you do not have to participate if you do not want to. Also, you may stop 
participating at any time.  
Alternatives 
Serotonin reuptake inhibitors (SRIs) are the standard medications for OCD. CBT consisting of EX/RP is the standard non-
medication treatment. Adding EX/RP or antipsychotic medications like risperidone (Risperdal) to SRI medication are 
standard methods for attempting to improve upon (i.e., augment) SRI response in OCD. 
Procedures
-Initial Screening: you have already met with clinic staff to review medical and psychiatric history, and you received a 
physical exam and blood and urine tests  
-Randomization: you will be randomly assigned to receive either the medication nabilone in combination with EX/RP 
(“medication and EX/RP”) or the medication nabilone alone (“medication only”) for four weeks 
-Nabilone: you will meet weekly with your study doctor to receive the medication nabilone for four weeks 
-EX/RP: if you are randomized to the “medication and EX/RP” group, you will also receive 9 sessions of Exposure and 
Response Prevention (EX/RP) from a study therapist while taking nabilone. If you are randomized to the medication only 
group, you will be offered 9 sessions of EX/RP at no cost after completing the study. 
-Independent Assessments: your symptoms will be evaluated by an independent evaluator during the study and one month 
after the end of the study by phone 
-Cognitive Testing: you will be asked to complete computerized learning/memory tasks before the intervention. 
Risks 
This study includes some risks and discomforts (please refer to the consent form for further details and explanations of 
these risks). These include possible side effects from nabilone such as drowsiness, dizziness/vertigo, dry mouth, and 
euphoria (feeing “high”).    
Benefits:
This research study is not meant to benefit you directly  
You may contact the study doctor, Dr. Helen Blair Simpson at 646-774-8110 with any questions.  


IRB#7239 (4/09/18) 
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CANNABINOID MEDICATION FOR ADULTS WITH OCD 
Informed Consent for Participation in Research 
PURPOSE and OVERVIEW: The purpose of this pilot research study is to test whether a medication called nabilone 
(Cesamet) on its own or in combination with a form of cognitive-behavioral therapy (CBT) called exposure and response 
prevention (EX/RP) does not cause unpleasant side effects in participants with obsessive-compulsive disorder (OCD), 
and to see if participants with OCD find it easy to take the medication repeatedly to help them feel better. Nabilone is a 
synthetic cannabinoid; it acts on the brain’s “endocannabinoid system,” which has been hypothesized to play a role in 
OCD. Nabilone is approved by the Food and Drug Administration (FDA) for the treatment of chemotherapy-induced 
nausea and vomiting. It is not FDA-approved for treating OCD. You are being asked to participate in this study because 
you have OCD. This consent form describes the study so that you can decide if you want to participate.   
VOLUNTARY: Participation in this research study is voluntary. If you decide not to participate, or if you later decide to 
stop participating, you will not lose any benefits to which you are otherwise entitled. A decision not to participate or 
withdraw your participation will not affect your current or future treatment at the New York State Psychiatric Institute or 
Columbia University. You will be notified of any significant new findings that may affect your willingness to continue to 
participate.  
ALTERNATIVE TREATMENTS/ALTERNATIVES TO PARTICIPATION: Serotonin reuptake inhibitors (SRIs) are 
the standard medications for OCD. These include clomipramine (Anafranil), fluoxetine (Prozac), fluvoxamine (Luvox), 
paroxetine (Paxil), sertraline (Zoloft), citalopram (Celexa), and escitalopram (Lexapro). CBT consisting of EX/RP is the 
standard non-medication treatment. Adding EX/RP or antipsychotic medications like risperidone (Risperdal) to SRI 
medication are standard methods for attempting to improve upon (i.e., augment) SRI response in OCD. 
PROCEDURES: All study procedures will take place at the New York State Psychiatric Institute (NYSPI) in New York, 
NY. Twenty OCD participants will participate. The study consists of several steps: 
1.
Screening: As part of the screening done in the Anxiety Disorders Clinic (IRB#7094R), you have already met with 
clinic staff to review your medical and psychiatric history, received a physical exam and tests of your blood and urine 
(including a urine toxicology and a blood pregnancy test if female), and filled out questionnaires about your symptoms. 
(Time commitment: approximately 2 hours) 
2.
Randomization: If you are eligible and sign this consent, you will then be randomly assigned to receive either the 
medication nabilone in combination with EX/RP (“medication and EX/RP”) or the medication nabilone alone 
(“medication only”) for four weeks. This “random assignment” means that you will be placed into one of the two 
groups by chance (like the flip of a coin). Neither you nor your study doctor can choose in which group you will be 
placed.
3.
Nabilone: All study participants will receive Nabilone for four weeks. You will meet weekly with your study 
doctor to receive the medication nabilone for four weeks and to review any side effects. You will take nabilone twice 
per day at a fixed dose for four weeks. 
4.
EX/RP: If you are randomized to the “medication and EX/RP” group, you will also receive 9 sessions of Exposure 
and Response Prevention (EX/RP) from a study therapist while you are taking nabilone. EX/RP is a form of 
cognitive-behavioral therapy that involves confronting the things that make you anxious (exposures) while also 
reducing your compulsive behaviors (response prevention). Therapy sessions will include therapist-supervised 
exposure, self-guided exposure as homework, and coaching in how to stop rituals. (Time Commitment: 9 EX/RP 
sessions over 4 weeks).
 
Note: If you are in the “medication only” group, you will be offered 9 sessions of Exposure and Response 
 
 
Prevention (EX/RP) therapy at our clinic at no cost once you have completed taking nabilone for four 
 
 
weeks) 
5.
Independent assessments: Your OCD and related symptoms will be evaluated by an independent evaluator who will             
not know whether you are receiving nabilone alone or in combination with EX/RP. These evaluations will occur 
during the study (Weeks 0,1,2,3,4) and one month after the end of the study (Week 8, by phone or in person). (Time 
Commitment: up to 1 hour per evaluation, 6 evaluations in total). 


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6.
Cognitive testing: You will be asked to complete computerized memory/learning tasks before the intervention (at 
Week 0). These tasks assess processes that are partly controlled by the cannabinoid system, and may provide clues 
about factors that influence treatment outcome.  This testing session can take up to 3 hours. 
RISKS AND INCONVENIENCES: 
Possible side effects from nabilone: Nabilone is a synthetic cannabinoid that is FDA-approved for the treatment of 
chemotherapy-induced nausea and vomiting and has also been used as an adjunct therapy for chronic pain management. It 
acts on the brain’s endocannabinoid system and is similar to tetrahydrocannabinol (THC), the primary psychoactive 
compound found naturally in Cannabis (or marijuana). Thus, nabilone is a controlled substance, and it may produce 
subjective effects in some that are similar to a marijuana-like “high.” Thus, anyone with a prior adverse experience with 
marihuana or any other cannabinoid (such as anxiety, panic, paranoia, perceptual distortions) should not participate in this 
study. Nor should any woman who is pregnant or nursing (since nabilone’s effects are unknown).  
 
In controlled clinical trials of nabilone, the most commonly encountered adverse effects (in > 20% of participants) 
include: drowsiness, dizziness/vertigo, dry mouth, and euphoria (feeling “high”).  Other adverse effects included: ataxia, 
sleep disturbance, dysphoria/depression, visual disturbance, trouble concentrating, hypotension, headache, nausea, 
disorientation, or depersonalization. Side effects may persist up to a few days after stopping nabilone, until the drug is 
fully gone from your body. This study will use a low dose of nabilone to minimize any potential adverse effects. 
 
Before taking any other medication, including over-the-counter medications (e.g., cough, cold, and allergy 
remedies), you must first discuss these medications with your study doctor because of the potential for drug-drug 
interactions that may change how nabilone, your regular medications, or your supplements work. If you require 
medications that are not safe to take with nabilone, you will not be able to participate in this study. You will not be asked 
to stop medications you are currently taking to participate in the study. 
 
When taking any new drug, you should exercise caution and not drive, operate machinery, or engage in other 
activities requiring mental alertness until you know how the drug will affect you. Because nabilone affects the brain, you 
must avoid other drugs that affect the brain, including alcohol, sedatives or hypnotics (e.g., benzodiazepines), and 
stimulants (e.g., amphetamine) since the brain effects are potentially additive. Use of illegal drugs (including marijuana or 
cannabis) during this study is forbidden. 
 
As with any drug, there may be associated risks and side effects, which cannot be predicted. If your symptoms 
become worse, if side effects are severe, or if your study doctor feels that taking nabilone is no longer in your best 
interest, administration of the drug will be stopped. Your study doctor will discuss any further treatment with you. Call 
your study doctor if you experience any side effects or if anything concerns you, whether or not you think these problems 
are related to the study drug. You may also call your regular doctor who may be informed (with your permission) by the 
study staff that you are participating in this study.  
EX/RP: EX/RP involves exposure to feared situations; exposures are intended to produce anxiety for therapeutic benefit. 
Some participants have not been able to complete EX/RP because of this. 
Delay in Treatment Initiation: If you are randomized to the “medication only” group, this will delay treatment with 
EX/RP for 4 weeks. If you have significant worsening of your psychiatric symptoms, we will stop your study participation 
and refer you to appropriate care. 
Questionnaires: Questionnaires take time and ask you about personal things, such as your thoughts and feelings. These 
interviews may make you tired or upset. If at any time the questions make you uncomfortable or tired, you can choose not 
to answer specific questions or ask to take a break or stop at any time. 
BENEFITS: Your OCD symptoms may improve with EX/RP but may not improve with nabilone. What we learn from 
your experience may help us understand more about the treatment of OCD, and it is possible that others might benefit in 
the future from your contribution. 
CONFIDENTIALITY: All records will be kept confidential to the extent permitted by law. Paper records will be stored 
in locked files; electronic data will be saved on computers protected by passwords, secure logon, and data 
communications security procedures. Your name and other personal identifying information will be stored in an 
electronically secure database at New York State Psychiatric Institute. Records will be available to research staff, and to 
Federal, State, and Institutional regulatory personnel (who may review the records as part of routine audits). A description 
of this clinical trial will be available on http://www.ClinicalTrials.gov, as required by U.S. Law. This Web site will not 
include information that can identify you. At most, the Web site will include a summary of the results. You can search this 
Web site at any time. 


IRB#7239 (4/09/18) 
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STUDY COMPENSATION: You will not be charged for any part of the study, including the interviews, medication, 
and EX/RP. You will be compensated $100 for participating in the independent assessment and the cognitive testing (paid 
in cash during your visit at Week4).  Additionally, you will earn between $24 and $60 in two of the cognitive tasks (paid 
in cash at the end of the cognitive testing session at Week0).
IN CASE OF INJURY: Federal regulations require that we inform participants about our institution's policy with regard 
to compensation and payment for treatment of research-related injuries. In case of injury, New York State Psychiatric 
Institute will provide short term emergency medical treatment, which has been determined to be necessary by New York 
State Psychiatric Institute’s doctors, and which is within the capability of New York State Psychiatric Institute to provide. 
In addition, we will provide assistance in arranging follow-up care in such instances. New York State Psychiatric Institute 
and Research Foundation for Mental Hygiene do not provide compensation or payment for treatment of research related 
injuries. However, you do not give up your legal right to seek such compensation through the court by participating in this 
research.  
QUESTIONS: Please ask questions about any part of this form or this study that you don’t understand. Take as long as 
you need to decide whether to participate in the study. You can also contact the Principal Investigator, Dr. Simpson, with 
questions at (646) 774-8110. You will be notified of significant new findings that may relate to your willingness to 
continue to participate. If you have any questions about your rights as a research participant, want to provide feedback, or 
have a complaint, you may call the New York State Psychiatric Institute Institutional Review Board (IRB) to speak with 
the IRB Main Office at (646) 774-7155 during regular office hours. An IRB is a committee that protects the rights of 
human subjects in research studies. You will be given a copy of this consent form to keep. 
DOCUMENTATION OF CONSENT 
I voluntarily agree to participate in this research study and have been given a copy of this consent form. I understand that I 
should not drink alcoholic beverages or use other drugs that affect my brain while I am in this study. If female, I agree to 
take measures to prevent becoming pregnant while taking nabilone.  
NAME__________________________________________ (print) 
Participant’s Name 
Signature________________________________________           Date___________ 
Participant’s Signature 
I have discussed the proposed research with this participant including the risks, benefits, and alternatives to participation 
(including the alternative of not participating in the research). The participant has had an opportunity to ask questions and 
in my opinion is capable of freely consenting to participate in this research. I have discussed how to prevent pregnancy 
with female participants. 
NAME_______________________________ (print) 
Consenting Investigator’s Name 
Signature______________________________ Date____________ 
Consenting Investigator’s Signature 


Form #PP2: HIPAA Authorization for Research ϰ.ϭϰ.1ϰ 
New York State Psychiatric Institute (NYSPI) 
Authorization to Use or Disclose Health Information during a Research Study 
Protocol Number: 
Principal Investigator: 
Name of Study: 
Before researchers can use or share any identifiable health information (“Health Information”) about you as part of the 
above study (the “Research”), the New York State Psychiatric Institute (NYSPI) is required to obtain your authorization. You agree 
to allow the following individuals and entities to use and disclose Health Information about youas described below: 
x
New York State Psychiatric Institute (NYSPI), your doctors and other health care providers, if any, and
x
The Principal Investigator and his/her staff (together “Researchers”).   Researchers may include staff of NYSPI, the New York
State Office of Mental Health (OMH), Research Foundation for Mental Hygiene, Inc. (RFMH), and Columbia University (CU),
provided such staff is a part of the study, and
x
WƌŽǀŝĚĞƌƐŽĨƐĞƌǀŝĐĞƐĨŽƌƚŚĞZĞƐĞĂƌĐŚĂƚh͕Ez^W/ĂŶĚͬŽƌZ&D,͕ƐƵĐŚĂƐDZ/ŽƌWd͕ŽƌCentral Reference Laboratories 
;EKI), iĨ indicated in the consent form.
1.
The Health Information that may be used andͬŽƌ disclosed for this Research includes:
All information collected during the Research as told to you in the Informed Consent Form.  
Health Information in your clinical research record which includes the results of physical exams, medical and 
psychiatric history, laboratory or diagnostic tests, or Health Information relating to a particular condition that is related  to 
the Research.
Additional information may include: 
2.
The Health Information listed above may be disclosed to:
Researchers and their staff at the following organizations involved with this Research: 
The Sponsor of the Research, 
and its agents and contractors (together, “Sponsor”); and  
Representatives of regulatory and government agencies, institutional review boards, representatives of the Researchers 
and their institutions to the level needed to carry out their responsibilities related to the conduct of the research.   
Private laboratories and other persons and organizations that analyze your health information in connection with 
this study 
Other (family members or significant others, study buddies, outside agencies etc.) Specify: 
3.
By giving permission to release your Health Information as described above, you understand that your Health
Information may be disclosed to individuals or entities which are not required to comply with the federal and state privacy laws
which govern the use and disclosure of personal Health Information by NYSPI.   This means that once your Health
7239
H. Blair Simpson
Endocannabinoid medication for adults with OCD
✔
✔
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NYSPI
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Form #PP2: HIPAA Authorization for Research ϰ.ϭ.1ϰ 
Information has been disclosed to a third party which does not have to follow these laws (e.g., a drug company or the Sponsor 
of the Research), it may no longer be protected under the HIPAA or NYS Mental Hygiene Law requirements but is subject to the 
terms of the consent form and may be subject to other state or federal privacy laws or regulations.  
4.
Please note that:
x
You do not have to sign this Authorization form, but if you do not, youŵĂǇ not be able to participate in the study or
receive study related care.  You may change your mind at any time and for any reason. If you do so, you may no
longer be allowed to participate in the study.  If you withdraw this Authorization the research staff and the Sponsor, if this
is sponsored research, may still use or disclose Health Information containing identifying information they already have
collected about you as needed to maintain the reliability of the research.  Any request to withdraw this Authorization
must be made in writing to (enter name and contact information below):
x
While the Research is going on, you may not be allowed to review the Health Information in your clinical research
record that has been created or collected by NYSPI.   When this research has been completed you may be allowed to see
this information.  If it is needed for your care, your Health Information will be given to you or your Doctor.
5.
This Authorization does not have an end date.
6.
You will be given a copy of this form after you have signed it.
I agree to the use and disclosure of Health Information about me as described above: 
__________________________________________                _____________________ 
Signature of ParƚŝĐŝƉĂŶƚ/ Legal Representative    
Date 
______________________________________ 
Printed Name of ParƚŝĐŝƉĂŶƚ 
______________________________________ 
ZĞůĂƚŝŽŶƐŚŝƉŽĨ>ĞŐĂůZĞƉƌĞƐĞŶƚĂƚŝǀĞƚŽWĂƌƚŝĐŝƉĂŶƚ;ŝĨĂƉƉůŝĐĂďůĞͿ 
We also ask you or your legal representative to initial the statements below: 
I have received a copy of the NYSPI/OMH Notice of Privacy Practices. 
H. Blair Simpson, MD/PhD, 1051 Riverside Drive Unit 69, New York, NY 10032

SAP_001.pdf: 
Cannabinoid Medication for Adults with OCD 
NCT02911324 
5/23/2016 
 


Study Summary: The purpose of this pilot research study is to test whether a medication called nabilone (Cesamet) on its 
own or in combination with a form of cognitive-behavioral therapy (CBT) called exposure and response prevention 
(EX/RP) does not cause unpleasant side effects in participants with obsessive-compulsive disorder (OCD), and to see if 
participants with OCD find it easy to take the medication repeatedly to help them feel better. Nabilone is a synthetic 
cannabinoid; it acts on the brain's "endocannabinoid system," which has been hypothesized to play a role in OCD. 
Nabilone is approved by the FDA for the treatment of chemotherapy-induced nausea and vomiting. It is not FDA-
approved for treating OCD. 
Study Design 
Conditions or Focus of Study: Obsessive-Compulsive Disorder  
Study Type: Interventional 
Primary Purpose: Treatment  
Study Phase: Phase 1/2 (for trials that are a combination of phases 1 and 2)   
Intervention Model: Parallel (participants assigned to one of two or more groups in parallel for the duration of the study) 
Number of Arms: 2 (number of intervention groups) 
Masking: Open Label (no masking is used; all involved know the identity of the intervention assignment)  
Allocation: Randomized 
Enrollment: Number of Subjects: 25 Type: Anticipated 
Arm Label: Nabilone  
Arm Type: Experimental  
Arm Description: Will receive nabilone at 1 mg BID over 4 weeks 
Arm Label: Nabilone and EX/RP 
Arm Type: Experimental 
Arm Description: Will receive nabilone at 1 mg BID plus therapist-guided Exposure and Response Prevention 
Therapy over 4 weeks. 
Inclusion/Exclusion 
Gender: Both 
Age Limits: 18-60 
Accepts Healthy Volunteers?: No 
Inclusion Criteria: 
- Age 18-60 
- Physically healthy, not pregnant 
- Primary OCD 
- Patient off all psychotropic medication (except selective serotonin reuptake inhibitors) and any other medication 
likely to interact with nabilone 
- Ability to provide informed consent 
- Ability to tolerate a treatment free-period  
Exclusion Criteria: 
- History of violence 
- Lifetime history of psychosis or bipolar disorder 
- Lifetime history of intellectual disability 
- Severe depression or suicide risk 
- Females who are pregnant or nursing 
- Patients planning to begin EX/RP or currently in EX/RP  
- Current substance use disorder or positive urine toxicology at screening, or any adverse reaction to a 
cannabinoid 
- History of any significant medical condition that may increase the risk of participation 
 


 
Interventions 
Intervention Name (use generic name if established): Nabilone 
Intervention Type: Drug 
Intervention Description (do not repeat information already included in arm/group descriptions): Nabilone is a 
synthetic form of THC and cannabinoid 1 receptor agonist. It acts on the brain's "endocannabinoid system," which 
has been hypothesized to play a role in OCD. 
Intervention Name: Exposure and Response Prevention Therapy 
Intervention Type: Behavioral  
Intervention Description: Exposure and Response Prevention Therapy (EX/RP) is a type of Cognitive-
Behavioral Therapy for OCD that involves intentionally confronting situations that trigger obsessional distress 
while refraining from doing compulsions.  
Outcome Measures 
Primary Outcome Measure 1: Feasibility of recruitment of patients with OCD into a study of nabilone 
Time Frame: Total participants who consent to participate for the duration of the study 
Safety Issue (Is this outcome measure assessing a safety issue?): No  
Primary Outcome Measure 2: Tolerability of nabilone (e.g. adverse events reported) 
Time Frame: Baseline (Week 0), Week 1, Week 2, Week 3, Week 4 
Safety Issue (Is this outcome measure assessing a safety issue?): Yes  
Primary Outcome Measure 3: Yale-Brown Obsessive-Compulsive Scale (YBOCS) 
Time Frame: Weeks 0 and 4 
Safety Issue (Is this outcome measure assessing a safety issue?): No  
Secondary Outcome Measures: Hamilton Depression Rating Scale, 17-Item (HDRS-17) 
Time Frame: Weeks 0 and 4 
Safety Issue?: No 
Statistical Analysis Plan 
For both the YBOCS and HDRS-17 measures, we will calculate change scores for the nabilone and nabilone+EX/RP 
groups based on the difference between Baseline (Week 0) and Week 4. This preliminary study is not designed to assess 
for statistical differences between groups, and thus only the overall magnitude of change between groups will be 
compared. We will assess feasibility of recruitment based on the total number of participants enrolled over the duration of 
the study. Finally, we will assess nabilone’s tolerability in OCD based on weekly self-reporting of side effects using a 
checklist drawn from the nabilone package insert, and any other adverse events that occur over the course of the study.