A Double-Blind, Placebo-Controlled Study of Memantine in Body Focused Repetitive Behaviors
Phase: PHASE2
Conditions: Trichotillomania (Hair-Pulling Disorder), Dermatillomania
Sponsor: University of Chicago

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A Double-Blind, Placebo-Controlled Study of Memantine in Body focused Repetitive 
Behaviors 
 
IRB20-1992 
Version: 05 
 
 
Jon E. Grant, J.D., M.D., M.P.H. 
University of Chicago 
Chicago, IL 
 
June 8, 2021 
 
NCT04792645 
 
 

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A Double-Blind, Placebo-Controlled Study of Memantine in Body Focused Repetitive 
Behavior Disorders 
 
This clinical trial will be conducted in the spirit of Good Clinical Practice and in 
accordance with this IRB approved protocol.  No deviation from the protocol will be 
implemented without the prior review and approval of the IRB except where it may be necessary 
to eliminate an immediate hazard to a research subject.  In such a case, the deviation will be 
reported to the IRB as soon as possible. 
 
Investigational Agent and Dosing 
 
 
Memantine 10mg to 20mg po qday 
 
Population 
 
 
The population to be studied for this trial is 100 men and women ages ≥18 years who 
have a current DSM-5 diagnosis of trichotillomania or skin picking disorder (i.e. a body focused 
repetitive behavior (BFRB)). 
 
Project Goals 
 
 
The goal of the proposed study is to evaluate the efficacy and safety of memantine in 100 
subjects with DSM-5 trichotillomania or skin picking disorder.  Subjects will receive 8 weeks of 
double-blind memantine or placebo. The hypothesis to be tested is that memantine will be 
effective and well tolerated in patients with BFRBs compared to placebo. The proposed study 
will provide needed data on the treatment of disabling disorders that currently lack a clearly 
effective treatment. 
 
Background  
 
Hair pulling disorder (i.e. trichotillomania) and skin picking disorder are often 
categorized under the umbrella term of body focused repetitive behaviors (BFRB) disorders. 
These repetitive, intentionally performed behaviors often cause noticeable cosmetic issues and 
may result in clinically significant distress or functional impairment (1-3). Although discussed in 
the medical literature for over one hundred years, and affecting all strata of society, there are no 
clear treatment approaches for people with these disorders (4). Behavioral therapy is generally 
regarded as the first-line treatment but trained therapists are difficult to find. In addition, there is 
no medication currently approved by the Food and Drug Administration for these disorders.  
It appears that trichotillomania and skin picking disorder may in fact share a common 
neurobiology which involves an excess of activation in the mesocorticolimbic area and a lack of 
top-down cortical control governing response suppression. The potential effectiveness of 
memantine in BFRBs may be via its antagonism of the NMDA receptors in the striatum (5-6) 
and its potential to improve aspects of cognition by modulating glutamatergic neurotransmission 
in the cortex.  

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Recent studies using diffusion tensor imaging demonstrated that both trichotillomania 
and skin picking subjects exhibited significantly reduced fractional anisotropy in anterior 
cingulate, pre-supplementary motor area, and temporal cortices (7-8). These data suggest that the 
disorganization of white matter tracts in motor habit generation and suppression may underlie the 
pathophysiology of these disorders (7-8). Neurochemically, motor habits may rely partially on 
the glutamate systems. Glutamatergic dysfunction has been implicated in the pathophysiology of 
these disorders (9-10). Pharmacotherapies, such as memantine, that target excessive 
glutamatergic drive may, therefore, be expected to correct the underlying pathophysiology and 
symptoms of BFRBs.  
Given the serious personal consequences associated with trichotillomania and skin 
picking disorder, and the likelihood of success of memantine in treating both disorders, the aim 
of the present study was to examine the efficacy and safety of memantine vs placebo in adults 
with trichotillomania or skin picking disorder using a double-blind, placebo-controlled design. 
 
We hypothesize that memantine will be more effective than placebo in reducing the 
frequency of hair pulling and skin picking and in improving overall psychosocial functioning 
after 8 weeks of treatment when compared to baseline. 
 
Primary Aim/Objective 
 
The aim of the present study is to examine the efficacy and safety of memantine vs 
placebo in adults with trichotillomania and skin picking disorder. 
 
Primary Endpoint(s):  
The primary efficacy measure will be the change in hair pulling or skin picking frequency 
and urges to pull hair or pick skin for the past week as indicated by change in total score on the 
NIMH Symptom Severity Scale (for TTM or Skin Picking)(11). The primary efficacy end points 
will be the change in these measures from baseline to week 8. 
 
Secondary Aim/Objective 
 
A secondary aim of the study is to examine the effects of memantine vs placebo on self-
report measures of hair pulling, skin picking, quality of life, and measures of mood and anxiety. 
 
Secondary Endpoint(s):  
Secondary efficacy measures include the change in number of days per week 
pulling/picking, the Clinical Global Impressions–Improvement Scale (CGI-I) rated global 
improvement of symptoms over time (results will be dichotomized as improved [CGI-I ratings of 
1 or 2 very much/much improved] or not improved [CGI-I ratings of 3-7]) (12), the self-report 
Massachusetts General Hospital Hairpulling Scale (13), the Skin Picking Symptom Assessment 
Scale (14), the Quality of Life Inventory (15), the Sheehan Disability Scale (16), the Hamilton 
Depression Rating Scale (17), the Hamilton Anxiety Rating Scale (18), the Tridimensional 
Personality Questionnaire (19), the Autism Spectrum Quotient (20), and the Barratt 
Impulsiveness Scale (21).  
 

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Methodology 
 
100 individuals with trichotillomania or skin picking disorder will be recruited for a 
double-blind, placebo-controlled pilot study in which memantine or placebo is administered in a 
1:1 fashion. All 100 subjects will have trichotillomania or skin picking disorder per DSM-5 
criteria. Following baseline measures, all subjects will be randomized to either memantine or 
placebo and seen every 2 weeks for the 8-week study period.  
 
Participants will be started at 10mg po qday for 2 weeks, then 20mg po qday for the 
remaining 6 weeks. Participants will only go up to the full dose if clinically needed. Efficacy and 
safety measures will be performed at each visit.   
 
The study will be conducted in accordance with the International Conference on 
Harmonization Guideline for Good Clinical Practice, all local ethical and legal requirements, and 
the World Medical Assembly (Declaration of Helsinki). The study protocol and procedures will 
be approved by the University of Chicago’s institutional review board prior to any recruitment. 
Written informed consent will be required for study participation. 
 
 
Randomization of drug will be conducted in blocks of eight, with 4 subjects in the 
memantine arm and 4 subjects in the placebo arm.  In event of an emergency, the blind will be 
assessable to the study subject by calling the pharmacy number listed on the medication bottle. In 
this event, the study subject will be discontinued from the medication, and a safety follow-up 
visit will be scheduled one week following discontinuation. The study subject will not know 
what arm of the study they are on otherwise. The investigational pharmacy will follow proper 
accountability procedures in regards to both randomization of the study drug and holding of the 
blind.  
  
Subjects:  
Inclusion criteria:  
1) men and women age ≥18 years;  
2) current DSM-5 trichotillomania or skin picking disorder; and  
3) Ability to understand and sign the consent form. 
. 
 
Exclusion criteria:  
1) Unstable medical illness based on history or clinically significant abnormalities on 
baseline physical examination  
2) Current pregnancy or lactation, or inadequate contraception in women of childbearing 
potential 
3) Subjects considered an immediate suicide risk based on the Columbia Suicide Severity 
rating Scale (C-SSRS) (www.cssrs.columbia.edu/docs)  
4) Past 12-month DSM-5 diagnosis of psychosis, bipolar disorder, mania, or a substance 
or alcohol use disorder 
5) Illegal substance use based on urine toxicology screening  
6) Stable dose of medications for at least the past 3 months 
7) Previous treatment with memantine 

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8) Cognitive impairment that interferes with the capacity to understand and self-
administer medication or provide written informed consent  
 
Baseline Assessments:  
Those subjects who appear appropriate for the study, based on telephone screening, will 
be invited for a baseline assessment. The duration of the baseline assessment will be 
approximately 90 minutes and will include the following: informed consent, demographic data, 
concomitant medications, and family history data. There will also be a physical examination 
(including weight, and vital signs, urine pregnancy test for women of childbearing years and 
urine drug screen). Finally, the subjects will undergo a psychiatric evaluation (using the MINI 
International Neuropsychiatric Interview). 
In addition, the following instruments will be completed at the screening visit: 1) NIMH 
Trichotillomania Symptom Severity Scale (or the same scale modified for skin picking); 2) 
Sheehan Disability Scale; 3) Massachusetts General Hospital Hairpulling Scale; 4) the 17-item 
Hamilton Rating Scale for Depression (HAM-D); 5) the 17-item Hamilton Rating Scale for 
Anxiety (HAM-A); 6) Clinical Global Impression (Improvement and Severity) scale; 7) 
Cambridge Caffeine Use Questionnaire; 8) The Dietary Fat and Free Sugar Questionnaire and 9) 
the Quality of Life Inventory; 10) Cambridge-Chicago Trait Scale (12); 11) the Skin Picking 
Symptom Assessment Scale (SP-SAS); 12) the Autism Spectrum Quotient (AQ-10); and the 
Barratt Impulsiveness Scale (BIS). In addition, subjects will undergo cognitive assessments at 
baseline and study endpoint.  
Cognitive Assessments: Assessments of cognitive control will be comprised of several valid 
paradigms (See below). These tasks are designed to probe dissociable neural circuitry and 
cognitive processes likely to be implicated in the pathophysiology of addictions. Task order was 
chosen arbitrarily and will be applied consistently across subjects, to minimize possible 
confounding factors of differences in task order across participants. 
 
The following tasks will be administered at baseline and final visits: 
 
 
-Stop Signal Task of Inhibitory Control (SST) 
 
 
-Intra-dimensional/Extra-dimensional Set Shift Task (ID/ED task) 
 
 
-One Touch Stockings Task (OTS) 
 
 
-Rapid Visual Processing Task (RVP) 
 
 
-Spatial Working Memory Task (SWM) 
 
 
-Cambridge Gambling Task (CGT) 
 
Following-Up Visit Assessments 
All follow-up visits will include all psychiatric measures (except the MINI which will be 
done at baseline only) and safety measures (adverse events, vital signs, C-SSRS). There will be 
four follow up visits for a total of five visits. 
 
Subject Compensation 
Subjects will be compensated $20 per visit, for a total of $100. Compensation will be given in 
the form of a check at the end of the study, as per University of Chicago protocol. 
 
Safety Assessments 
Safety and tolerability will be assessed using spontaneously reported adverse events data, 
Columbia–Suicide Severity Rating Scale (C-SSRS), vital signs, and by evaluating premature 

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termination. Safety assessments (C-SSRS, sitting blood pressure, heart rate, adverse effects, and 
concomitant medications) will be documented at each visit. Subjects who are an immediate 
suicide risk will be removed from the study and appropriate clinical intervention (e.g. 
hospitalization) will be arranged. Urine pregnancy tests will be performed at the initial visit. 
Subjects who have a positive urine pregnancy test will be excluded from the study. Assessment 
of side effects will be done at each visit. AEs will be coded by system organ class (SOC) and 
preferred term (PT) using the Medical Dictionary for Regulatory Activities (Med- DRA) 
Version11.1. The incidences of all AEs will be summarized descriptively. In terms of vital signs, 
those subjects with abnormal blood pressures will be assessed for symptoms of hypo- or 
hypertension. Asymptomatic subjects will be evaluated each visit for changes in vital signs. In 
the case of hypertensive emergencies (BP greater than 210/120), appropriate referral to the 
emergency room will be made. In the case of hypotension (BP less than 90/60), participants will 
be evaluated for symptoms of hypotension and if symptomatic, appropriate interventions will be 
made. 
 
Subject Withdrawal 
If a subject withdraws from the study, all instruments administered at the screening visit 
will be completed at the final visit.  These will be conducted when the subject is able to come in 
for an early termination visit.  Withdrawn subjects will be given the phone number of the 
principal investigator as well as the phone numbers of local resources for trichotillomania and 
skin picking.   
 
Data and Safety Monitoring Plan 
1. Responsibility for Data and Safety Monitoring 
The PI will have overall responsibility for monitoring the integrity of study data and 
participant safety.  
2. Procedures for Monitoring Participant Safety 
The PI will implement the following procedures to ensure data integrity and the safety of 
participants during the study. 
• A number of elements of the research plan are intended to minimize the risks of 
study participation. If subjects become actively suicidal with intent and plan to 
kill themselves, the PI will evaluate them and refer them for immediate non-study 
treatment. Any participant endorsing suicidal thoughts with intent and plan will be 
immediately evaluated by the PI and referred to a higher level of care if clinically 
indicated.  
• The PI will evaluate patient safety and resolve any safety issues if necessary, as 
such issues arise. The PI will also be responsible for preparing written summary 
reports of adverse events and will prepare a written report summarizing any 
decisions that are made pertaining to participant disposition.  
• Data integrity and confidentiality will be safeguarded as discussed above in the 
Data Management and Statistical Analysis section under Research Methods.  
 
Monitoring Committee 
We will establish a monitoring committee and define in detail its role, its composition, and its 
operating procedures for reviewing patient safety and data from this study.  The monitoring 
committee, comprised of three individuals independent of personnel involved in the study, 

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including a psychiatrists and a statistician, will come together via conference call yearly. The 
committee will use a standardized approach employing contemporary bio statistical, 
psychiatric/psychological, and ethical principles to review study design and interim data every 
year. The committee will audit the records from the study and will ensure the data are being 
collected, managed and protected. The committee will have the ability to ask for more frequent 
reviews at any time if they deem it necessary. In addition, the PI will inform the committee of 
any serious adverse event.  
The PI will prepare a specific report for the committee in advance of each meeting. Attention 
will be given to data quality and timeliness, recruitment, risk versus benefit, adverse events and 
other factors that could affect study outcome.  
3. Reporting Adverse Events 
• Any serious adverse event will be reported to the Institutional Review Board 
(IRB) at the University of Chicago in a full written report within 10 working days 
of the event. For fatal/life-threatening serious adverse events, the PI will notify 
the IRB Chair by phone immediately. 
• Any moderate adverse event which appears definitely, probably, or possibly 
related to study participation will be reported to the University of Chicago IRB in 
writing within 20 working days. 
• Any mild adverse event will be summarized in the IRB annual progress reports. 
 
Statistical Analysis 
 
Design/Randomization 
The study is a double-blind, placebo-controlled study. Participants will be randomized (1:1) to 
receive memantine or placebo by the University of Chicago Investigational pharmacy in block 
sizes of eight, using computer-generated randomization with no clinical information.  
 
Due to the pandemic of COVID19, study participants can perform their baseline and follow-up 
visits online using encrypted Zoom instead of in person visits. All inventories will be assessed. 
Blood samples and urine toxicology, however, will be at the discretion of the study PI. In cases 
where they are considered medically necessary, the participant can have them drawn locally and 
submitted to the study team. 
 
Efficacy Analysis 
For statistical analysis, the full-analysis set will be defined as all participants who took at least 1 
dose of the study drug and had at least 1 post-randomization primary efficacy assessment. The 
safety-analysis set will be defined as all randomized participants who took at least 1 dose of the 
study drug and completed at least 1 post-randomization safety assessment.  Participants with 
trichotillomania and skin picking disorder will be grouped as one BFRB group. 
 
We will compare the baseline characteristics of both groups using Fisher’s exact test for 
categorical variables and the t test for continuous variables. We will calculate adherence to 
treatment, based on the number of pills returned at each visit, as the number of 
pills taken divided by the number of days in the study × 100%. 
 
Primary endpoint analysis 

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The primary outcome measure will be the change from first randomization visit to study 
endpoint in total composite score on the NIMH Trichotillomania/Skin Picking Symptom 
Severity Scale.  
 
The primary analysis of efficacy for continuous measures will be analysis of variance (ANOVA), 
with terms for treatment to assess differences between treatment groups in the change from first 
randomization visit to endpoint using the last observation carried forward. The primary analysis 
for global improvement and response categories will be the Cochran-Mantel-Haenszel test using 
the last observation carried forward. The primary analysis for ≥5% reduction in weight will be 
Fisher’s exact test using the last observation carried forward.  
 
Secondary endpoints analyses 
Secondary outcome measures will include the change from first randomization visit to study 
endpoint in CGI severity and improvement scales, self-reported hair pulling behavior using the 
MGH-HPS, self-reported skin picking behavior using the SP-SAS, the change in depressive and 
anxiety symptoms, change in quality of life, and impacts on personality markers. We will use a 
longitudinal analysis comparing the rate of change of the outcome during the treatment period 
between groups. The difference in rate of change will be estimated by random regression 
methods.  The model for the mean of the outcome will include terms for treatment, time, and 
treatment-by-time interaction. To account for the correlation of observations within participants, 
we will use SAS procedure MIXED with a first-order antedependence covariance structure. The 
longitudinal analyses will use all available observations from all time points from all participants 
who completed a randomization visit evaluation.  
 
Safety analyses 
We will evaluate differences between groups in the incidence of treatment-emergent adverse 
events using Fisher’s exact test. Descriptive statistics will be used to evaluate changes in 
laboratory values, blood pressure and heart rate.  
 
Sample Size 
The sample size was calculated for the primary endpoint of change from randomization. For 80% 
power to compare the change from randomization, assuming a true effect size of 0.5 between 
treatment group and the placebo group, 30 participants with a BFRB will be needed in each 
treatment group based on a 2-group t test at the .05 level of significance. Given the low rates of 
adverse events expected with memantine, we expect few drop-outs from the study.  
 
Data Management Plan 
Data collected will consist of demographic data, subjective (self-report questionnaires, interview 
responses, ratings), and physiological (weight, heart rate and blood pressure). Access to 
individually identifiable private information about human subjects will be limited to Dr. Grant 
and their staff and will be collected specifically for the proposed research project. All collected 
data will be stored utilizing a 4-digit subject identification code, linked to separately stored 
identifying information via a coded log only available to the PI.  
 
The gender ratio of trichotillomania and skin picking disorder have been estimated to be 
approximately 3:1 (female:male).  We will also make every effort to include a racially/ethnically 

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diverse study population. The year 2010 Chicago census is 2,695,598 (US Census Bureau, 2011). 
The year 2010 Chicago race distribution is as follows: white 47.1%, African/African-American 
33.9%, Asian/Asian-American 6.2%, Native American 1.0%, or other race/not identified 
(11.8%). A total of 28.9% of the population also identified as Hispanic/Latino allowing for a 
diverse population sample (year 2010, US Census Bureau, Chicago, IL). We will make every 
effort to ensure that members of both genders and diverse racial, ethnic, and socioeconomic 
groups are adequately represented in the proposed study. 
 
The PI will implement the following procedures to ensure data integrity and the safety of 
participants during the study: A number of elements of the research plan are intended to 
minimize the risks of study participation. For example, the study exclusion criteria exclude 
patients who are experiencing clinically significant suicidality or require a higher level of care 
than outpatient. If this is indicated, the PI will evaluate them and refer them for immediate non-
study treatment (for example, inpatient or additional pharmacologic treatment).  The PI will 
carefully monitor ratings on the Columbia Suicide Severity Rating Scale and the Hamilton 
Depression Rating Scale; any participant endorsing suicidal thoughts, will be immediately 
evaluated by the PI and referred to a higher level of care if clinically indicated. The PI will 
evaluate patient safety at each visit and resolve any safety issues more frequently if necessary, as 
such issues arise.  The PI will also be responsible for preparing written summary reports of 
adverse events and will prepare a written report summarizing any decisions that are made 
pertaining to participant disposition.  
 
 
Ethical Considerations 
This study will be conducted according to US and international standards of Good Clinical 
Practice (FDA regulations 21 CFR 312 for IND studies and FDA guidance E6) for all studies.  
Applicable government regulations and University of Chicago research policies and procedures 
will also be followed. 
 
This protocol and any amendments will be submitted to the University of Chicago Institutional 
Review Board (IRB) for formal approval to conduct the study.  The decision of the IRB 
concerning the conduct of the study will be made in writing to the investigator.   
 
All subjects for this study will be provided a consent form describing this study and providing 
sufficient information for subjects to make an informed decision about their participation in this 
study.  This consent form will be submitted with the protocol for review and approval by the 
IRB.  The formal consent of a subject, using the IRB-approved consent form, will be obtained 
before that subject is submitted to any study procedure.  This consent form must be signed by the 
subject and the investigator-designated research professional obtaining the consent.  
 

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