Brain Imaging of Nicotinic Acetylcholine Receptors in Tobacco Users and Nonusers
Phase: PHASE1
Conditions: Tobacco Use Disorder, Tobacco Smoking
Sponsor: Johns Hopkins University

Brain Imaging in Tobacco Smokers During a Quit Attempt
NCT04055467
12/4/2021

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Date: ___12/04/2021_________________ 
Principal Investigator: Elise M. Weerts 
Application Number: IRB00173536 
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1.
Abstract
a.
Provide no more than a one page research abstract briefly stating the problem, the research
hypothesis, and the importance of the research.
The primary goals of this project are to examine the role of the α7-nicotinic acetylcholine receptors 
(nAChRs) in tobacco use disorder. Tobacco smoking represents the leading cause of preventable 
illness and death in the United States (US)(1)with ~22% of adult men and 16% of adult women in 
the US being current smokers. Only 6% of smokers who attempt to quit are successful long-term(1), 
and relapse occurs most often during the first 8 days of quitting(2). One of the greatest barriers to 
smoking cessation is the nicotine withdrawal syndrome that emerges within 12 hours of abstinence 
(3, 4), and include intense craving/urges to smoke that are strongly associated with relapse (5). 
Nicotine is the main psychoactive component of tobacco, and produces its effects are via nicotinic 
acetylcholine receptors (nAChRs) which are comprised of arrangements of alpha (α2-α10) and/or 
beta subunits (β2-β4). The most common types of nAChRs are those containing β2* subunits 
(*denotes assembly with other subunits) and homomeric versions which contain only α7 subunits. 
Preclinical and clinical studies have demonstrated that β2* nAChR are important for the 
reinforcing effects of nicotine, but appear to play a lesser role in expression of nicotine withdrawal. 
However, preclinical evidence suggests α7 nAChR may modulate the rewarding aspects of 
smoking and nicotine craving,(6)and thus α7 nAChR may provide an important novel target for 
pharmacotherapeutic interventions for smoking cessation. Surprisingly, the extent to which chronic 
tobacco use affects α7 nAChR in humans has yet to be explored.  
The proposed outpatient study will quantify α7 nAChR availability in 18 tobacco cigarette smokers 
with tobacco use disorder (TUD) using human Positron Emission Tomography (PET) with a α7 
nAChR selective radiotracer (18F-ASEM) and explore the potential relationship of α7 nAChR 
availability to clinically relevant measures of tobacco abstinence (e.g., withdrawal and craving, 
cognitive impairment). Participants’ α7 nAChR availability will be compared to α7 nAChR 
availability of historical controls (healthy volunteers who were nonsmokers). Study participants 
and historical controls will be matched by race, sex, and age. Smokers will also complete an 8-day 
quit attempt during which they can receive an incentive (money), contingent upon target exhaled 
carbon monoxide (CO) in early abstinence, and target urinary cotinine levels at later abstinence 
stages. These data are critical towards our understanding of the effects of cigarette smoking on α7 
nAChR, a potential pharmacotherapeutic target to promote smoking cessation. 

 
 
 
 
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2. 
Objectives (include all primary and secondary objectives) 
 
The proposed studies will help fill gaps in existing research by determining if in α7 nAChR 
availability in nicotine-dependent cigarette smokers is higher when compared to nonsmoker 
historical controls using PET imaging and the α7 nAChR selective radiotracer 18F-ASEM. The 
study will also explore whether distribution volume (VT), a measure of α7 nAChR availability in 
tobacco users influences clinically relevant measures of tobacco abstinence (e.g., withdrawal and 
craving, cognitive impairment), tobacco/nicotine use, and number of days abstinent during an 8-
day quit attempt during which smokers can receive escalating payments contingent upon providing 
objective evidence (breath CO and urinary cotinine) of smoking abstinence. 
 
Primary Objective 1: To examine α7-nAChR availability in tobacco smokers versus healthy 
nonsmoker controls.  
Hypothesis 1: α7-nAChR availability (VT ) will be higher in heavy smokers with TUD than 
nonsmoker historical controls.  
 
Primary Objective 2: To examine the relationship between α7-nAChR availability and 
clinically relevant measures of tobacco abstinence.  
Hypothesis 2: α7-nAChR availability (VT ) in smokers will be positively associated with severity 
of nicotine dependence.  
 
Hypothesis 3: Greater α7-nAChR availability (VT ) in smokers will be associated with higher 
craving/urges to smoke and greater cognitive/memory impairment during abstinence when 
compared to their baseline levels (smoking as usual).  
 
Hypothesis 4: Higher α7-nAChR availability (VT ) will be correlated with fewer abstinence days 
during the 8-day practice quit attempt. 
 
3. 
Background (briefly describe pre-clinical and clinical data, current experience with procedures, 
drug or device, and any other relevant information to justify the research) 
Public Health Significance. The World Health Organization (WHO) has estimated smoking-
related costs across the globe to be about $500 billion USD a year. There is extensive evidence that 
nicotine, the primary component in tobacco, produces it effects via nAChR(7). Tobacco smoking (or 
administration of nicotine) produces mild euphoria, and improvements in mood, attention and 
cognitive function, as well as physiological effects such as increased heart rate, sweating, dizziness, 
and nausea. Smoking abstinence is associated with a nicotine withdrawal syndrome, which includes 
negative affective symptoms such as increased anxiety, depression, irritability, as well as intense 
craving/urges to smoke, and impairments in attention and working memory. Symptoms of nicotine 
withdrawal emerge within 12 hours of smoking abstinence, lasting 2-4 weeks, and are influenced by 
nicotine dependence severity(4). During quit attempts, smokers are most vulnerable to relapse during 
early abstinence. Although  FDA-approved treatments (nicotine replacement therapy, bupropion, 
and varenicline) improve quit success rates, especially short-term, the fact that 80-85% of smokers 
still ultimately relapse highlights the need for better understanding of the neurobiological 
mechanisms involved in smoking maintenance, nicotine withdrawal, and relapse(8). 
nAChR. α4β2 nAChRs have a high affinity for nicotine and are distributed throughout the CNS, 
including the mesocorticolimbic dopamine system. While the predominant receptor nAChR subtype 
consisting of β-subunits are more ubiquitous, the pentameric homomeric α7 nAChR has been 
implicated as a potential target for therapeutic intervention due to its high calcium permeability and 
second messenger system involvement (9). α7 nAChRs have lower nicotine affinity than α4β2 
nAChRs, and are predominantly located in the hippocampus, cortex, and subcortical limbic regions. 

 
 
 
 
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Importantly, α7 nAChRs are localized within the ventral tegmental area (VTA) and nucleus 
accumbens (NA) terminating to dopamine cell bodies, which suggests a likely influence on the 
dopamine reward system and contribution to aspects of smoking and relapse(6). Studies in rodents 
and humans have shown exposure to chronic nicotine produces an upregulation of nAChRs 
containing β2* subunits and such upregulation is associated with nicotine dependence. Activation of 
β2∗ nAChRs facilitates nicotine self-administration. In contrast, α7 nAChRs negatively modulate 
both nicotine reinforcement and β2∗ nAChR function in the mesolimbic dopamine system. 
Selective stimulation of α7 nAChRs reduces nicotine reward and motivation to self-administer 
nicotine, and augments the aversive effects of nicotine (10). This is consistent with growing evidence 
that there are compensatory interactions affecting the balance between β2* vs. α7 nAChRs. This 
suggests a working hypothesis that brain α7 nAChR may play a role in negative craving and 
withdrawal severity. With high nicotine exposure, α7 nAChRs desensitize more rapidly, and at 
higher nicotine concentrations than α4β2 nAChRs (11-14). Such desensitization processes are thought 
to be a critical step in the development of nicotine tolerance and dependence. Indeed, the most 
effective FDA-approved medication for smoking cessation (varenicline) acts as a full α7nAChR 
agonist and a α4β2 nAChR partial agonist consistent with current theories of a role α7 subtype in 
long-term continuance of smoking cessation(15).  
PET Imaging of nAChR. Human in vivo imaging study of *β2 nAChRs is well established in the 
literature with multiple studies demonstrating partial occupancy of *β2 nAChRs after exposure to 
second hand tobacco smoke (19%)(16), or just a few puffs of a tobacco cigarette (50%)(17) . Other 
studies have demonstrated an upregulation of *β2 nAChRs in tobacco smokers in first few days of 
quitting smoking, when compared to non–smokers, and levels normalize by 6 to 12 weeks (18-21). In 
contrast, the lack of a suitable radioligand for α7 nAChR hampered this area of research in human 
subjects. Previous published attempts yielded over 20 radioligands insufficient for clinical use (22-32). 
In 2013 our team developed 18F-ASEM, a high α7 affinity (Ki = 0.3 nM) and selective radioligand 
with excellent specific binding in rodents(32) and baboons(33), and completed the first successful in-
human PET experiments(34). To date, there has been no demonstration of the effects of tobacco use 
on α7 nAchR in vivo in the human brain. α7 nAChRs regulate a variety of behaviors including 
cognitive process of attention, learning and memory, as well as emotion, and reward; the same 
processes are involved in the maintenance of smoking behaviors, craving and withdrawal. It is 
unclear why tobacco users often smoke so many cigarettes each day, given that relatively low 
amounts of tobacco use saturates the α4β2 nAChRs. Moreover, upregulation of *β2 nAChRs was 
not correlated with clinical measures of abstinence (severity of nicotine dependence, withdrawal or 
craving/urges to smoke) in prior studies(20, 35). Thus, the α7 nAChR receptor is a likely mechanism 
for modulating the degree to which tobacco users smoke each day. Our study will utilize 18F-ASEM 
to examine if a7-nAChR availability is higher in heavy tobacco smokers when compared to 
nonsmoking historical controls. We will also explore the possible role of the a7-nAChR in 
craving/urges to smoke, severity of nicotine dependence, severity of withdrawal and cognitive 
impairment during nicotine/tobacco abstinence, and propensity to relapse. 
 
4. 
Study Procedures 
a. Study design, including the sequence and timing of study procedures   
(distinguish research procedures from those that are part of routine care). 
 
Protocol Overview 
 
 
The proposed proof-of-concept pilot research study will be conducted at the Johns Hopkins 
Behavioral Pharmacology Research Unit (BPRU) and the Johns Hopkins Hospital (JHH) PET 
Imaging Center. All participants will be healthy volunteers and all procedures will be for 
research purposes.  Tobacco smokers (n=18) will be invited to complete a smoking as usual visit 

 
 
 
 
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with an MRI, followed by an 8-day quit attempt with 2 study visits during the 8-day period. 
Participants who successfully maintain 1 day of abstinence will complete a PET scan with the α-
7 nAChR radiotracer 18F-ASEM. At all visits, exhaled CO and urinary cotinine levels will be 
determined. For Visits 2 and 3, participants will receive incentive payments contingent on 
biomarkers of smoking abstinence (CO and cotinine) to promote smoking abstinence. Measures 
that are clinically relevant for smoking cessation (e.g., symptoms of nicotine withdrawal and 
craving; impaired cognitive performance; changes in resting heart rate), number of cigarettes 
smoked per day, and number of days abstinent until return to smoking (lapse) will be examined 
in relation to α-7 nAChR availability. In addition, we will access PET imaging data from 
healthy non-smoking controls who completed 18F-ASEM PET studies under IRB approved 
protocols NA_00091295 and IRB00185590 (PI: Dean F. Wong) who match participants from 
the present study on characteristics such as age, sex, and BMI.  
 
Human Subjects Involvement, Characteristics, and Design  
 
 
Subjects aged 21-50 will be recruited via include newspaper, radio and other advertisements 
in the greater Baltimore-Washington D.C. area. Subjects will be recruited to yield a broadly 
representative sample of the community. Based on census data, the greater Baltimore area 
population is mostly Caucasian (62%) or African American (29%); the remaining 9% is mostly 
Asian (6%) and persons reporting more than two or more races (2%). About 8% of the 
population report Hispanic or Latino origin. We anticipate a similar distribution for the current 
study sample. 
 
All potential subjects will be screened by telephone using a standardized initial 
questionnaire, which includes demography, alcohol and drug use patterns and associated 
problems, and a brief personal medical and mental health status. This telephone screening 
addresses the major inclusion/exclusion criteria for the study and quickly rules out respondents 
who disqualify. We anticipate a highly adequate recruitment flow of subjects. In earlier studies, 
we completed a total of approximately 600 phone call inquiries and telephone screens annually. 
Based on our recent experience, we estimate we will consent and assess about 4 persons for 
each subject who completes study all procedures (i.e., approximately 72 participants will be 
consented in order to obtain 18 study completers). This is necessary to have a sufficient pool of 
subjects who meet inclusion/exclusion criteria and who can be matched to historical controls by 
sex, race/ethnicity, and age.  
 
Subjects who appear eligible based on the telephone interview are informed of the general 
nature of the study, including study duration and commitment, introductory information about 
the medication, the nature of the measurement procedures, and compensation amount and 
arrangements. Interested volunteers are then invited for an in-person interview at the BPRU 
facilities on the Bayview Campus.  
 
Screening. 
 
 
Subjects who appear eligible and provide written informed consent will complete an in-
person screening visit that includes a standard battery of instruments, a medical history, physical 
examination, vital signs, and standard blood chemistry and hematology laboratory tests. Prior to 
any research participation, subjects provide written informed consent using the Institutional 
Review Board (IRB) approved form; consent is obtained by IRB-approved members of the 
research team. Upon enrollment, subjects are assigned a unique study identifier (ID). Only 
subject IDs will be used to code all data forms. 
 
Multiple assessment instruments will be done to determine who should be included and who 
excluded, and to provide measures that may be included as covariates in analyses. The Mini-
International Neuropsychiatric Interview (MINI, v.7)(36) for DSM-5 will be used to assess TUD, 

 
 
 
 
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other SUD, and psychological disorders. Tobacco, alcohol, and illicit drug use will be 
characterized using the 90-day Time Line Follow Back (TLFB)(37). The presence of tobacco use 
disorder and severity of nicotine dependence will also be assessed using standard questionnaires 
such as the Fagerstrom test for nicotine dependence. The Shipley Institute of Living Scale (38) 
will be used to ensure adequate reading comprehension for completion of study assessment 
instruments; a score of 18 or higher is required for study enrollment. Exhaled breath carbon 
monoxide (CO) and urinary cotinine will also be assessed at screening to determine smoking 
status. Volunteers who appear eligible for study participation at the end of the screening visit 
will complete a screening ECG (see below).  
 
ECG Screening. 
 
 
The study team physicians with JHBMC privileges will review all health information to 
determine initial study eligibility.  Any participants with a history of heart disease, or blood 
pressure that exceeds a systolic blood pressure of 150 mmHg or a diastolic blood pressure of 90 
mmHg will be excluded. Only healthy volunteers are eligible. A 12-lead ECG will be conducted 
in those that appear to meet all other study inclusion/exclusion criteria as an additional 
screening procedure. If the ECG shows any abnormalities, a credentialed cardiologist will 
determine if the abnormality may be clinically significant (incidental findings).  Participants that 
have clinically relevant ECG abnormalities will be excluded from further study participation. 
 
MRI Procedures.  
 
 
Eligible participants will have an MRI scan of the head to identify the anatomy of the brain 
for co-registration with the PET images. The MRI exam will take approximately 60 min. During 
this MRI, participants will also undergo echo-planar imaging scans during rest, and a diffusion-
weighted imaging scan. Resting-state and diffusion-weighted imaging scans will be used to 
determine resting-state functional brain connectivity. Prior to the MRI, each participant will be 
asked to complete a standard questionnaire to determine if the participant has any metal in the 
eyes or head. The purpose of this questionnaire is to ensure that the participants are safely able 
to enter the MRI area. After answering this questionnaire, a small number of participants may be 
required to undergo two anterior-posterior (AP) skull x-rays to further determine if it is safe for 
them to enter the MRI area. If the skull x-rays are necessary, the MRI staff will explain the x-
ray procedure to the participant. The results of the x-rays will then determine if it is safe for the 
participant to enter the MRI area. An extremely small number of participants are determined to 
be unsafe to enter the MRI area based on the questionnaire and/or x-rays. If this should happen, 
or if the participant chooses not to have the x-rays, the participant will be removed from the 
study. 
 
Practice Quit Attempt  
 
 
Following the screening procedures, eligible smokers will be asked to refrain from tobacco 
smoking for at least 1 day and try to remain abstinent for 8 days. We selected an a 8-day quit 
attempt in order to capture data during the period in which relapse occurs most often (i.e., the 
first 8 days of quitting)(2).   During this 8-day period, smokers will complete 2 study visits (e.g., 
day 1, and 8 of the quit attempt) during which breath CO and urine samples to determine levels 
of cotinine and clinically relevant measures for smoking cessation (e.g., withdrawal, craving, 
cognitive/memory performance, vital signs) will be assessed. Cigarettes smoked per day will 
also be assessed retrospectively.  
 

 
 
 
 
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To promote smoking abstinence, a validated incentive intervention (contingency 
management)(39-41) will be used. Specifically, at each visit, smokers will receive $40 payment 
for attendance, and additional incentive payments for providing breath and urine sample(s) at 
each visit that meet defined abstinence criteria for breath CO and urinary cotinine consistent 
with tobacco/nicotine abstinence (42, 43). CO provides a specific biomarker for recent smoking. A 
threshold of <6ppm will be used as this level reduces misclassification of individuals who 
engage in some smoking as "abstinent"(44). Urinary cotinine has a longer half-life (16 h) than 
breath CO. Cotinine progressively declines over consecutive days of abstinence, and a lack of 
such a decrease is a biomarker of nicotine use. Using criteria established previously39-41, 
abstinence on day 8 will be cotinine levels below the abstinence threshold (<100 ng/mL). To 
maximize the number of smokers available for imaging after 1 day of abstinence, a second 
reinforced quit attempt will be allowed on the following week, if they are unable to reach the 
abstinence criteria on their first attempt. Once the initial quit is verified, a reset scheme typically 
used in incentive interventions will be employed. Provision of a sample that exceeds the 
abstinence criterion will result in no incentive earnings for the day and a reset to the beginning 
of the schedule. When an incentive is not earned, the $40 payment for making the visit should 
be sufficient compensation to support continued study attendance, and re-try of the quit attempt. 
This strategy is based prior BPRU studies that employed the same incentive intervention and 
reset scheme. The combined use of both CO and cotinine as abstinence biomarkers provides the 
strong method to verify and reinforce early phase abstinence when residual cotinine is being 
eliminated, and longer abstinence when cotinine has high sensitivity42, 44. CM (using similar 
parameters and incentive earning schedules) is a well validated intervention. CM is used to 
promote smoking cessation in treatment-reticent populations including opioid-maintained 
smokers(48-50)  and smokers with schizophrenia as a stand-alone treatment or combined with 
smoking cessation medication(45, 51).  
  
PET Scan Procedures:   
 
 
Tobacco smokers (n=18) will complete a single 18F-ASEM PET scan on day 1 of the 8-day 
quit attempt, assuming they are able to remain abstinent from cigarettes prior to the scan 
(verified by exhaled breath CO).  
 
Prior to the PET scan participants will complete procedures i-iv. 
 
(i)Facemask Procedures:   
 
 
Each participant will have a facemask custom-fitted to facilitate maintaining the same 
position of the head for the PET scan. The facemask will be constructed on the day of the PET 
scan. To make the mask, a soft, warm piece of plastic will be laid across the participant’s face. 
The plastic touches the participant’s face from his/her forehead to the middle of his/her nose. 
The plastic molds to the shape of the participant’s face and hardens as it cools. The facemask 
will take approximately 10 minutes to construct. 
 
(ii)Pregnancy Testing for Females prior to all PET scans:  
 
 
All female participants will be required to provide a urine sample for pregnancy testing. The 
pregnancy test must be negative for the participant to continue with the study. 
 
(iii)Catheters and blood sampling:  
 

 
 
 
 
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All participants will have two catheters, a venous and arterial, placed prior to the start of the 
PET scan. The first venous catheter will be inserted into a vein of one arm for the injection of 
the radiotracer. The arterial catheter will be inserted into a radial artery of the other arm by an 
anesthesiologist for rapid withdrawal of blood specimens for analysis of radiotracer. The wrist 
of each participant will be infiltrated intradermally via a 30 gauge needle with 2 mL 1% (20 mg 
(0.3 mg/kg for most adults) lidocaine hydrochloride before the insertion of the arterial line to 
provide local anesthesia. If participants experience discomfort at the site of insertion of the 
arterial line, then they will be administered subcutaneous injections of 2 mL 1% (20 mg (0.3 
mg/kg for most adults) lidocaine hydrochloride. This dose corresponds to 10% of the maximal 
recommended dose and 5% of the dose associated with effects on the central nervous system. 
During the PET scan, up to forty blood samples (a total blood volume of approximately 150 
mL) will be collected for metabolite and radioactivity analysis of the radiotracer.   
 
(iv)Transmission and emission scan:   
 
 
After the catheters are placed the participant will be placed in the PET scanner and complete 
a 6 to 10 minute transmission (attenuation) scan performed before or after the PET scan.  The 
participant will then have the PET scan performed during which an intravenous injection of 15 
mCi of 18F-ASEM will be administered. Dynamic PET data will be acquired during scanning for 
approximately 90 minutes following tracer injection.  
 
Retrospective Healthy Control Data:   
 
We will use historical PET imaging data from prior studies that used the same 18F-ASEM 
radiotracer studies under IRB approved protocols NA_00091295 and IRB00185590 (PI: Dean 
F. Wong), to compare α-7 nAChR availability in the non-smokers in those studies to smokers in 
the current study. All participants for whom we access their historical data consented to the use 
of their data in future investigations.  
 
b. Study duration and number of study visits required of research participants. 
 
Participants will have up to 1 month to complete all study procedures, from the time the 
informed consent is signed up to the completion of all study procedures. The number and type 
of visits (4 total) for study participants is as follows: 
 
Baseline Visit 1: Baseline (smoking as usual) cognitive tests, self-report instruments,  
Vital signs, breath and urine sample collection, and MRI.  
 
Set quit date (should be the day before PET on Visit 2). 
 
Visit 2:  
Vital signs, breath and urine sample collection.  
 
 
PET scan (pending CO-verified tobacco/nicotine abstinence)  
Cognitive tests and self-report instruments  
 
Visit 3: Day 8 of the 8-day practice quit attempt  
 
 
Vital signs, breath and urine sample collection.  
Cognitive tests and self-report instruments  
 
 
 
 
 
 
 
 
c. Blinding, including justification for blinding or not blinding the trial, if applicable. 

 
 
 
 
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This is not applicable for this study, as experimental procedures will be the same for all 
study participants.  
 
d. Justification of why participants will not receive routine care or will have current therapy 
stopped. 
 
Participants in this study will be healthy volunteers who use tobacco products and are not 
seeking smoking cessation treatment. Routine care for any medical illness that may arise during 
participation will not be affected. Individuals currently attempting to quit smoking using a form 
of therapy such as nicotine replacement therapy (NRT) or behavioral counseling or who have 
used a tobacco cessation treatment in the past 3 months will not be eligible.  
 
e. Justification for inclusion of a placebo or non-treatment group. 
 
There is no placebo or non-treatment group in the present study.  
 
f. Definition of treatment failure or participant removal criteria. 
 
Participant participation is voluntary. Participants may withdraw at any time for any reason. 
Participants will also be withdrawn from the study if the participant experiences an event 
making it unsafe for the participant to continue to in the study. Participants may also be 
withdrawn the study if the principal investigator feels it is in the best interest of the participant, 
or participant is unreliable in attendance of study visits. 
 
g. Description of what happens to participants receiving therapy when study ends or if a 
participant’s participation in the study ends prematurely. 
 
Upon completion or premature exit from the study, all participants who are smokers will 
undergo our standard smoking cessation counseling session, guided by the NCI booklet 
“Clearing the Air: Quit Smoking Today” and will receive a referral card to a tobacco quit line. 
Individuals who have used a smoking cessation product in the past 3 months or are currently 
attempting to quit smoking using a form of treatment (e.g., behavioral counseling) will not be 
eligible. Thus, the practice quit attempt smokers will engage in for this study will not serve as a 
substitution for other treatments. For participants who do not meet full study inclusion/exclusion 
criteria participation ends after screening procedures. Participants who meet all 
inclusion/exclusion criteria may also be discontinued if they are unable to complete all inpatient 
procedures (e.g., are unable to schedule or complete procedures in a timely manner) or where 
continuation may increase risk as determined by study physicians. The study investigators may 
also discontinue study participants for other reasons not known at this time such as for failing to 
follow a particular protocol requirement. Participants with a positive toxicology or pregnancy 
test are excluded from participation. Participants may be discontinued if they are unable to meet 
the 1-day smoking abstinence criteria prior to the PET scan per the study protocol. Participants 
will be compensated for each of the procedures completed regardless of whether they continue 
in the study or not; earnings for uncompleted procedures or completion bonuses will be 
forfeited. Discontinuation of a study participant can result in the need to recruit additional 
research volunteers.  
 
 
5. 
Inclusion/Exclusion Criteria 
 

 
 
 
 
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Inclusion criteria: 
• Healthy volunteers who are regular tobacco smokers  
• Aged 21 - 50 years old 
• Willing to make themselves available for the duration of the study and are willing to follow 
study procedures and research unit policies. 
• Women of child bearing potential must agree to use a reliable method of birth control 
during the study and for 1 month after all study procedures have concluded  
• Self-report currently smoking 10 or more cigarettes per day 
• Self-report regular smoking for a period of 2 or more years 
• Provide an exhaled breath carbon monoxide (CO) exceeding 8 ppm 
• Provide a positive cotinine urine test 
• Provide a negative cannabis urine toxicology screen 
• Meet DSM-V criteria for moderate to severe tobacco use disorder (TUD).  
 
Controls (non-smokers): We will access a historical database of research participants that 
completed intake assessments and 18F-ASEM PET scans under our other comparable research 
studies (e.g., NA_00091295; IRB00185590; PI: Wong). Specifically, we will select males and 
females from our database of healthy nonsmokers who meet the following inclusion criteria: a) 
males and females aged 21-50 years, b) no current or past history of tobacco smoking, b) confirmed 
negative breath CO at intake and pre-PET (<4ppm). Exclusion criteria were the same as described 
below for smokers in the current protocol. We will select controls who are best matched for age, sex 
and race distributions to smokers in this study.  
 
Exclusion Criteria: 
• Meets DSM-V for AUD or SUD Disorder (excluding TUD for smokers) 
• Meets DSM-V Psychiatric Disorder; in or in need of treatment 
• Use of illicit drugs within last 90 days; positive urine toxicology screen  
• Clinically-significant abnormality on ECG 
• Unstable hypertension (BP > 150/90) 
• Serum creatinine and hepatic enzymes (AST, ALT) outside of normal limits 
• History of seizures, seizure disorder or closed head trauma 
• HIV positive 
• Weight > 350 lbs 
• < 5th grade reading level as determined via a Shipley score of less than 18 
• Use of smoking cessation products in last 3 months or undergoing current quit attempt using 
another treatment  
• If female: has a positive pregnancy test, is pregnant, lactating, or planning pregnancy  
• Significant anatomical abnormalities on MRI of the brain (e.g., enlarged ventricles, brain 
lesions)  
• Use of prescribed medications in last 3 months; over the counter drugs or herbal 
supplements which may be counter indicated as determined by study physician may also be 
excluded 
• Presence or history of drug allergy, or allergic disease diagnosed and treated by a physician. 
• Any serious medical condition in whom participation is contraindicated.  
• Any condition which would preclude MRI (e.g., implanted metal, severe claustrophobia). 
• Radiation exposure in the last year that when combined with the study protocol would 
exceed the annual limits. 
 
To determine eligibility, the medical records will be reviewed by study physicians, and 
psychological assessments and full inclusion/exclusion criteria will be reviewed by Dr. Weerts.  

 
 
 
 
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6. 
Drugs/ Substances/ Devices 
a. The rationale for choosing the drug and dose or for choosing the device to be used. 
b. Justification and safety information if FDA approved drugs will be administered for non-FDA 
approved indications or if doses or routes of administration or participant populations are 
changed. 
c. Justification and safety information if non-FDA approved drugs without an IND will be 
administered.  
 
PET radiotracer: 18F-ASEM 
 
18F-ASEM is a selective, high-affinity (Ki = 0.3 nM) antagonist for α7-nAChR that was 
developed for PET imaging. 18F-ASEM was developed, synthesized and first tested in humans 
at the JHU PET center(52-54), and will be used in the proposed studies under IND 118,496. Dr. 
Dean F. Wong (Co-I on this protocol) submitted documents to the FDA which transfers 
ownership of this IND to Dr. Martin Pomper (Packet date 2/27/2020). 18F-ASEM will be 
synthesized by our dedicated team of PET radiochemists and will meet all USP Chapter <823> 
acceptance testing criteria. Radiochemical purity at end of synthesis will be > 99% with high 
specific activity. A single dose of 15 mCi of 18F-ASEM will be administered to each participant 
during the PET scanning procedure by intravenous bolus administration. This dose represents an 
exposure that conforms to the "ALARA" (as low as reasonably achievable) principle for 
radiation exposure. Based on highly analogous studies in nonhuman primates, this dose should 
provide the minimum image quality necessary to quantify α7-nicotinic cholinergic receptor 
densities in the brain while exposing the human volunteers to an ED of radiation that should be 
less than 5 rem per year (the State of Maryland’s approved occupational limit, 21 CFR 361.1). 
Indeed, a single injection of 15mCi of 18F-ASEM will only expose participants to 0.95 rem, over 
5 times less than the recommendation annual radiation exposure limit. 18F-ASEM is the 
appropriate radiopharmaceutical for our studies. It has excellent test-retest reproducibility(55), 
and has been used successfully and safely in PET studies in healthy normal volunteers and 
schizophrenic patients(54).  
 
7. 
Study Statistics 
a. Primary outcome variable. 
b. Secondary outcome variables. 
c. Statistical plan including sample size justification and interim data analysis. 
d. Early stopping rules. 
 
Derivation of outcome variables. There is no appropriate, reliable reference region for 18F-ASEM 
due to the widespread distribution of α7 nAChR in the human brain. BPND (non-displaceable 
binding potential which requires a measure of absolute non-specific binding) is not appropriate for 
quantification of this radioligand. Volumes of Interest (VOI) will be generated by spatially 
normalizing(56) a standard VOI template(57) to individual subjects on Spoiled Grass (SPGR) 
sequenced MRI volumes. VOIs are: amygdala, ventral striatum, cingulate, hippocampus, and frontal 
cortex. α7 nAChR availability (VT) will be obtained for each VOI by plasma reference graphical 
analysis (PRGA); we have previously demonstrated that PRGA showed more robust estimates of 
VT than the two-compartment model, as measured with time dependency of estimates and the 
magnitude of inter-subject variability(54). VT is a standard outcome for many receptor binding 
radiopharmaceuticals.  
 
Sample size and Power Analysis: We propose a total sample size of 36, which includes 18 smokers 
accrued in the proposed study, plus an equal number (n=18) of healthy nonsmokers selected from a 

 
 
 
 
Page 11 of 24 
 
pooled sample of our historical database, matching for basic demographic variables (age, sex, and 
race) of our smokers.  
 
The primary outcome variable is VT determined via 18F-ASEM PET scans in 5 VOI (anterior 
cingulate, hippocampus, frontal cortex, amygdala, and ventral striatum). We completed a power 
analyses using R, and the package ‘pwr’ version 1.2-1, using pooled baseline data (total n=21) and 
our test-retest data (n=8) for 18F-ASEM VT. Across all regions, TRV averaged 6% (+/- 0.9%, range 
5.1% to 8.8% across regions), which is well below the standard accepted reproducibility level of 
10%. Assuming between group comparisons (18 Smokers vs. 18 controls), with an α of 0.05 (one 
tailed test), we examined our power to detect a 20% difference between groups (smokers vs. 
nonsmokers). Cohen's d for the VOIs, calculated as the average difference in mean VT for a 20% 
increase in smokers/pooled standard deviation (SD), ranged from 1.09 (amygdala) to 1.3 (frontal 
cortex). Our analysis indicated we will have 0.94 to >0.98 power to detect 20% change in our VOIs. 
If the change is more modest (e.g.,15%), calculated Cohen's d ranged from 0.82 (amygdala) to 0.98 
(frontal cortex), and we would still have >0.80 power to detect group differences of 15% in anterior 
cingulate, hippocampus, frontal cortex, and ventral striatum, but may be slightly underpowered for 
amygdala (0.77 power) for a 15% group difference.  
 
Statistical Analysis Plan: First, the baseline characteristics of the participants (age, race, sex, 
socioeconomic status etc.) will be summarized and compared by group (smokers vs. controls). The 
primary and secondary outcomes variables as defined in 4.3 Outcome variable, and summarized 
above, will be our dependent variables. Descriptive statistics will be generated; continuous variables 
will be reported as means (SD) and categorical variables as frequencies and percentages. The 
primary outcome variable (VT), and all secondary outcome variables will undergo data cleansing 
and CAPA (Corrective/Preventive Measures-based confirmation of accuracy and missing data). We 
will perform exploratory data analyses (stem-leaf displays, box plots, histograms, and Q-Q plots), 
and if necessary, appropriate data transformations will be performed. Our intention is to frequency 
match groups as closely as possible for age, race, and sex, and to match male and female smokers 
for nicotine dependence severity as appropriate, to reduce these potential confounds. To determine 
if smokers differ from controls in α7 nAChR availability (hypothesis 1a), we will use a general 
linear model. VT (or a transformation, if necessary) will be the dependent variable with group 
(smokers and controls) as the independent variable. All VOI-based statistical analyses will be done 
with SPSS (IBM Corp., 2013) or R (Foundation for Statistical Computing, 2011). After the initial 
VOI-based analyses, we will also use Statistical Parametric Mapping (SPM (56, 58) to identify and 
confirm differences in VT between groups without restrictions of VOIs. The same models used in 
VOI-based analyses will be applied to the voxel-based analyses. We plan to use a threshold level of 
p = 0.05, FDR-corrected, and the minimal cluster size at 50 voxels (~0.4 ml). To determine if VT 
will be associated with clinically relevant measures of tobacco withdrawal during abstinence in 
smokers, we will construct separate models with VT of hypothesized VOIs as the dependent 
variable, and change from baseline to abstinence (day 1) for: craving, withdrawal discomfort, 
negative affect, and cognitive/memory performance as independent variables. The Holm-Bonferroni 
method will be applied to correct for multiple comparisons.  
 
Resting-state functional brain connectivity analysis: Resting-state data will undergo standard 
preprocessing step, including slice timing correction, realignment/motion correction, co-registration 
across runs and to the SPM EPI template (59), with smoothing, motion sensoring or “scrubbing” (60), 
physiological artifact correction (61), and 36-parameter confound regression and spike regression (62). 
DTI and structural MRI data will undergo realignment, registration to an average template, and 
deterministic tractography will be conducted in order to determine laplacian harmonics for 
connectome harmonic analysis. Seed-based, region-of-interest-based (63), independent component-
based (59), graph-theory/network-analysis-based(64), and connectome-harmonic-based metrics (65) of 

 
 
 
 
Page 12 of 24 
 
connectivity within and among commonly identified resting-state networks (66, 67)), including the 
default mode, salience, executive control, and fronto-parietal attention networks will be determined 
using standard software. These metrics will be compared between groups (smokers and matched 
controls) using a two-sample T-test.  
 
8. 
Risks 
a. Medical risks, listing all procedures, their major and minor risks and expected frequency. 
 
This study involves several separate procedures, each of which entails some risk of discomfort 
or side effects. These risks are discussed by procedure. Participants will receive a thorough 
description of all potential risks in the consent document.  
 
Screening procedures: This study involves questions about dangerous or illegal behavior, 
psychiatric history, a medical history, and a physical exam. There is risk of a possible breach of 
confidentiality. There is also a small risk that participants will become upset during the 
screening interview. Participants’ names will be recorded only on the screening, informed 
consent, and necessary medical and payment forms. Anonymous participant identification 
numbers will be used on all other forms and labeling of biological fluids and test results.   
 
ECG Screening. A 12-lead ECG will be conducted in those that appear to meet all other study 
inclusion/exclusion criteria as an additional screening procedure. These screening ECG results 
may identify a potentially clinically significant cardiac abnormality (i.e., incidental finding).  
The screening ECG only identifies an “incidental finding” and is not a full diagnostic ECG. One 
of the study physicians will contact the participant and discuss the nature of the ECG findings, 
and if results are clinically significant, the physician will recommend that the participant see 
his/her physician for diagnostic evaluations, or if needed, refer the participant to an appropriate 
physician. We will provide a copy of the ECG report. Participants that have clinically relevant 
ECG abnormalities will be excluded from further study participation. Disclosure of these 
incidental findings to the participant may be distressing to the participant. 
 
MRI. The MRI does not involve any radiation exposure, but does involve exposure to magnetic 
fields. Although scientists do not know a great deal about the possible long-term effects of 
exposure to magnetic fields, the risks of the MRI scanning procedure are presumed to be 
minimal. Because the MRI instrument contains a powerful magnet, it could be painful if 
subjects have any metal objects in or on their body; Subjects who report metal in their body are 
excluded from participation. At-risk subjects (e.g., metalworkers) who may have metal in their 
eye will also complete a skull x-ray to determine presence of metal prior to the MRI exam (see 
below). Some people find the MRI unpleasant or claustrophobic.  
 
MRIs will be reviewed by a faculty neuroradiologist, who may identify brain abnormalities 
(incidental findings), some of which may be clinically significant. These MRI results only 
identify “incidental findings” as the research MRI is not a full diagnostic MRI. One of the study 
Physicians will contact the participant and discuss the nature of the findings (e.g. benign, 
congenital abnormalities etc.) if it is not exclusionary, and if results are clinically significant, 
will recommend that the participant see his/her physician and if needed refer the participant to a 
physician. Disclosure of these incidental findings to the participant may be distressing to the 
participant.  
 
Skull x-ray. As indicated in the MRI procedures, participants may be asked to undergo two skull 
x-rays to determine the participant has no metal in their skull.  This is a standard safety 
procedure employed by the Johns Hopkins MRI staff to verify it is safe for the participant to 

 
 
 
 
Page 13 of 24 
 
enter the MRI area. If participants undergo the skull x-ray there will be an additional 0.01 rem 
of radiation exposure to the participant. 
 
PET and Radiologic Procedures. Studies that employ PET are approved by the Johns Hopkins 
University IRB and the Federal Drug Administration (FDA). Subjects will undergo one PET 
imaging session using the α7-nAChR radiotracer 18F-ASEM. Use of 18F-ASEM in the current 
protocol will be under IND# 118,496 (approved 1/2/2014), recently transferred from Co-I Dr. 
Wong to Co-I Dr. Martin Pomper. Potential risks are detailed below. 
 
1. Catheters: All participants will have two catheters, one venous and one arterial, placed 
prior to the start of each PET scan. The venous catheter will be inserted into a vein of 
one arm for the injection of the radiotracer. The arterial catheter will be inserted into a 
radial artery of the other arm by an anesthesiologist for rapid withdrawal of blood 
specimens; up to 40 blood samples (a total blood volume of approximately 150 mL) will 
be collected for metabolite and radioactivity analysis of the radiotracer.  
2. Lidocaine. Lidocaine, a local anesthetic, is administered prior to arterial catheter 
placement. There is the possibility of an allergic reaction following the topical placement 
or the injection of the lidocaine. Lidocaine will not be administered to participants with 
known allergy to lidocaine. Lidocaine may cause drowsiness, tremors, and decreased 
respirations for a few hours after administration. The maximal amount of lidocaine the 
participant will receive in this study is 10% of the maximal recommended dose and 5% 
of the dose at which any side effects (such as drowsiness or tremors) would be expected. 
Therefore, side effects from lidocaine are unlikely. 
3. Radiotracer. Only high specific activity 18F-ASEM is being administered in this study. 
Each participant will receive approximately 15 mCi of 18F-ASEM during the PET 
scanning procedure as a bolus injection. This is a tracer dose of drug; therefore, no 
behavioral or adverse effects of the radiotracer are anticipated. There is a low risk of an 
allergic reaction following the injection of the radiotracer. Dr. Wong has extensive 
experience with 18F-ASEM under IRB approved protocol (NA_00091295). 18F-ASEM 
will be used at very small doses, well below levels with any known pharmacologic 
activity. No adverse events are expected. Subjects are carefully monitored for any side 
effects after receiving the radiotracer. There is currently no information on the effects 
18F-ASEM on an embryo or fetus; however, it is known that higher levels of radiation 
can cause damage to an embryo or fetus. 
4. Radiation exposure. 18FASEM is an imaging agent that includes radioactivity. A single 
dose of 15 mCi of 18F-ASEM will be administered to each participant during the PET 
scanning procedure intravenously bolus administration, exposing participants to 0.95 
rem. From the PET transmission scan, participants will receive an additional 0.0026 rem 
of external radiation exposure. If participants are required to have the skull x-rays 
performed to verify it is safe for the participant to enter the MRI area, the radiation 
exposure will increase by 0.01 rem. Thus, the total possible maximum amount of 
radiation exposure from the combined internal and external sources of radiation in this 
study will be about 0.9626 rem, which is below the allowable annual radiation exposure 
limit of 5 rem per calendar year set by JHU. The amount of radiation exposure is also 
within the limits of allowable occupational exposure in the state of Maryland 
(21CFR361.1). Overall, the radiation exposure in this study conforms to the "ALARA" 
(as low as reasonably achievable) principle for radiation exposure. 
5. Women for child bearing potential: To avoid unknown risks for the fetus, women of 
child bearing potential must use an effective form of birth control and will have urine 
pregnancy tests at screening and prior to all procedures; only women with a negative 
pregnancy test may participate. 

 
 
 
 
Page 14 of 24 
 
6. Other risks. Several additional risks occur throughout the course of the PET study. PET 
risks include a risk of pain, bleeding or infection from the catheters used for PET scan 
procedures. In rare cases, fainting or infection could occur. 
 
Nicotine/tobacco withdrawal: Abstinence after chronic daily use of tobacco cigarettes is 
associated with nicotine/tobacco withdrawal discomfort that may include increases in symptoms 
such as anxiety, irritability, craving, sweating, and difficulty concentrating(68-71). These 
symptoms are time limited, not associated with severe health consequences, not medically 
dangerous, and typically resolve on their own within 2 weeks. 
 
Treatment Diversion: Individuals who are attempting to quit smoking using another treatment 
method (e.g., NRT) or who made a quit attempt in the last 3 months, using smoking cessation 
medications are also are not eligible to participate. Some tobacco users could delay seeking 
other treatment in order to participate.  
 
Blood collection: Blood collected during the PET scan will be less than the amount taken for 
routine blood donation. Blood draw procedures involve minimal risks, such as a slight risk of 
discomfort at the intravenous site. A small amount of bleeding under the skin will produce a 
bruise in about 5% of cases. The risk of temporary clotting of the vein is about 1%. The risk of 
infection or significant blood loss is less than 1 in 1000. In rare cases, fainting could occur. To 
minimize risks associated with venipuncture, experienced medical personal using sterile 
equipment, will perform the blood draws.  
 
 
b. Steps taken to minimize the risks. 
 
Recruitment and Informed Consent:  Participants will be identified through the media using 
IRB-approved advertisements displayed on forums such as social media, newspaper/magazine, 
and radio. At the initial contact, the research coordinator will discuss the study purpose and 
requirements with the participants. Prior to the start of the screening, subjects provide written 
informed consent using a document approved by the Johns Hopkins IRB. The Project 
Coordinator will read and, as necessary, explain the consent form to the volunteers before they 
are asked to sign it. Volunteers will receive a copy of the signed consent form to keep. The 
consent form describes the experimental procedures and their associated risks. It provides an 
assurance that volunteers may ask and will receive answers to questions, assures volunteers that 
their participation is voluntary and may be terminated by them at any point if they wish. The 
consent form also gives the conditions for investigator termination of research participation, and 
provides names and numbers to contact in the event of questions or concerns. Prior to 
completing any assessment materials, subjects are breathalyzed and must provide a 0mg% 
reading to participate in the interview. Subjects also must provide a urine sample and test 
negative for illicit drug use and for pregnancy. Subjects with any contraindications are excluded 
from participation. Subjects are permitted to discontinue their participation at any time. Subjects 
are carefully and continually monitored throughout their participation. In case of an adverse 
event, a physician or nurse practitioner is on call for assistance.  
 
Insuring protocol comprehension: We exclude potential subjects with literacy below the 5th 
grade reading level as determined using the Shipley-2 because of concerns about their ability to 
adequately participate in the study procedures. Many of our behavioral/subjective measures are 
self-administered and require basic literacy and language skills. If subjects are not at a 5th grade 
level, they have difficulty responding accurately to the study questionnaires.  
 

 
 
 
 
Page 15 of 24 
 
Psychosocial assessments: The risk of distress or personal discomfort elicited during testing is 
minimized by the use of standardized assessment procedures widely used in research settings. In 
addition, all study staff are trained in nonjudgmental interview techniques and crisis intervention 
procedures.  
 
ECG Screening. A 12-lead ECG will be conducted in those that appear to meet all other study 
inclusion/exclusion criteria as an additional screening procedure. There is a small risk of some 
skin irritation from the pads used to do the ECG.  Any irritation is usually mild and will resolve 
on its own. Sometimes a small amount of your body hair where the ECG pads will be placed 
must be shaved to help pads stick to the skin. Only a small amount of hair would be shaved, but 
may cause some temporary skin irritation. There is a risk the screening ECG results may 
identify a potentially clinically significant cardiac abnormality (i.e., incidental finding).  The 
screening ECG only identifies an “incidental finding” and is not a full diagnostic ECG. One of 
the study physicians will contact the participant and discuss the nature of the ECG findings, and 
if results are clinically significant, the physician will recommend that the participant see his/her 
physician for diagnostic evaluations, or if needed, refer the participant to an appropriate 
physician. Disclosure of these incidental findings to the participant may be distressing to the 
participant. We will provide a copy of the ECG report. Participants that have clinically relevant 
ECG abnormalities will be excluded from further study participation.  
 
MRI: The risk of pain associated with metal in the body will be reduced by taking the following 
steps: 1) Subjects will be instructed to inform the investigator if they have metal objects on or in 
their body that cannot be removed (e.g., bone pin, skull plate, braces). 2) Subjects will only be 
allowed to receive an MRI scan if the implant or device is made of non-magnetic materials. 3) 
Skull x-rays will be used to determine if at risk subjects (e.g., metalworkers) have metal in their 
eye prior to the MRI exam. If they are found to have metal in their eye, they will not be allowed 
to continue in the study. Subjects are also informed that the MRI scanner produces banging 
sounds, and that some people find these conditions unpleasant or claustrophobic. In addition, if 
the MRI scan identifies a significant brain abnormality (e.g., enlarged ventricles, brain lesions) 
subjects will be terminated from the protocol (exclusion criteria). One of the study Physicians 
will contact the participant and discuss the nature of the findings (e.g. benign, congenital 
abnormalities etc.) if it is not exclusionary, and if clinically significant, will recommend that the 
participant see his/her physician. Participant notification of incidental findings from the MRI are 
required by the JHU IRB. We will provide a copy of the radiology report of the abnormality. If 
the participant does not have a physician, contact information for one will be provided.  
 
PET and Radiologic Procedures: We have safely studied research subjects with a wide variety 
of psychiatric, drug use and medical disorders under similar protocols. A physician is present 
throughout the PET procedure and monitors the subject to insure the comfort and well-being, 
and respond appropriately to remedy and adverse effects. Vital signs will be taken prior to the 
tracer injection, every 5 minutes for the first 20 minutes after the injection, then every 15 
minutes for the next 30 minutes, then every 30 minutes until the end of the PET scan, and once 
just after the scan is completed. During the PET scan, continuous ECG monitoring will be 
conducted. ECG monitoring of subjects during the scan is utilized as a safety precaution. If any 
clinically relevant abnormalities are detected, a printout is obtained and appropriate intervention 
in consultation with the staff cardiologist will be done. 
 
IV and arterial catheters. Participants will receive lidocaine hydrochloride intradermally (2 mL 
1%; 20 mg or 0.3 mg/kg for most adults) before the insertion of the arterial line to provide local 
anesthesia. If participants experience discomfort at the site of insertion of the arterial line, then 
they will be administered subcutaneous injections of 2 mL 1% lidocaine hydrochloride. This 

 
 
 
 
Page 16 of 24 
 
dose corresponds to 10% of the maximal recommended dose and 5% of the dose associated with 
effects on the central nervous system. The arterial line will be monitored by a physician and 
nuclear medicine technologist staff throughout the entire procedure. The arterial line will be 
removed by a study physician who will ensure there is no residual bleeding and will advise the 
subjects on the monitoring and precautions for the next 24 hours following its removal. An 
arterial line is necessary for analysis of PET imaging data; if one cannot be placed, then the PET 
scan will be cancelled. 
 
Radiation: Participants that have had research related exposure to ionizing radiation that in 
combination with the study’s estimated radiation exposure would result in a cumulative 
exposure that exceeds recommended exposure limits of 5 rem per year would be excluded from 
participation. The amount of radiation exposure in the current protocol is within the limits set 
forth by 21CFR361.1. 
 
Women of child bearing potential and risk to the fetus: Females who are pregnant, planning to 
become pregnant or nursing will be excluded from study participation. All females must have a 
negative pregnancy test at screening and prior to PET procedures. A positive pregnancy test at 
any point during the study results in study termination. Women of child bearing potential must 
also use a medically acceptable method of contraception for the duration of the study.  
 
Nicotine/Tobacco withdrawal: Symptoms of nicotine/tobacco withdrawal are time limited and 
typically resolve without clinically-significant problems. In case of an emerging or adverse 
event, a study physician is available via pager for assistance. 
 
Treatment Diversion: The informed consent process will clearly indicate that this research is not 
a substitute for other treatments. As previously described, participants will be instructed that 
should they withdraw from the study at any point to pursue treatment elsewhere; they will still 
be compensated for their participation up until that point in the study. At the end of the last 
study visit, smokers will be offered a standard smoking cessation counseling session, guided by 
the NCI booklet “Clearing the Air: Quit Smoking Today” and will receive a referral card to a 
tobacco quit line(72). Participants can decline this session. 
 
Blood collection: To minimize risks associated with venipuncture, experienced medical 
personnel, using sterile equipment, will perform the blood draws. The total volume of blood 
drawn in the protocol is under the Johns Hopkins IRB ceiling of 500 ml and is not expected to 
lead to discomfort or health concerns.  
 
Confidentiality: Our staff is well trained in the matters of confidentiality. Participants’ names 
will be recorded only on the screening, informed consent, and necessary medical and payment 
forms.  All medical information obtained will be handled in accordance with HIPAA 
regulations. Anonymous participant identification numbers will be used on all other forms and 
labeling of biological fluids and test results. Subject numbers will be used to code all data forms 
for computer entry and storage. All information gathered will be kept in locked research staff 
offices or file cabinets.  Only research staff will have access to participant research records.  
Study findings are reported using group data only. No information about subjects will be 
provided to anyone outside of the study including family members, third persons or 
organizations. Historical healthy control data we will access will also be entirely de-identified.  
Experimental sessions will take place in the BPRU, Johns Hopkins 550 Building and the Johns 
Hopkins Clinical Research Unit. The limits of confidentiality (e.g. suspected child abuse or 
neglect, or harm to self or others) will be discussed in detail with the participants during the 

 
 
 
 
Page 17 of 24 
 
informed consent process. To reduce the likelihood of patient records disclosure we have a 
Certificate of Confidentiality for this study. 
 
Images specific to the protocol will be shared with collaborator Dean Wong at Washington 
University in St. Louis. The JHU study team will use re-coded image IDs to label the images 
when in transit to Washington University in St. Louis.  Dr. Weerts will track the accession 
numbers or, for those images lacking accession numbers, MRN with scan date and time for 
requested images specific to each protocol. Dr. Weerts will use the Washington University in St. 
Louis Central Neuroimaging Data Archive (CNDA) XNAT Desktop Uploader to share images 
and recoded data with Washington University in St. Louis. The CNDA was established in 2004 
at Washington University, as the Neuro informatics Research Group flagship installation of 
XNAT (a database widely used and developed at Washington University in St. Louis). Dr. 
Wong (Washington University in St. Louis Joint PI) will ensure the CNDA will share a report of 
all the files uploaded with their upload date and file size along with the csv log files for the 
uploads with Johns Hopkins.  Only copies of the data will be transferred to the Washington 
University Institute of Radiology in Dr Wong’s account by secure electronic transfer . All 
original data will remain at JHM or JHU. A data dictionary of data that will be shared is 
provided in the eIRB protocol. 
 
 
c. Plan for reporting unanticipated problems or study deviations. 
 
All adverse events, protocol deviations, and other unanticipated problems are required to be 
reported to the PI, and other applicable study team members assisting with the protocol, as soon 
as possible.  The PI and study team members will review the information pertaining to the 
event.  For adverse events, the review will include a determination of severity, relationship to 
investigational drugs and/or protocol procedures, and reportability of the adverse event as 
outlined in our data safety and monitoring plan document.  For protocol deviations, the review 
will include a determination as to why it occurred, the significance of the deviation, and any 
corrective action to be taken (e.g., amending the protocol).  All other unanticipated problems 
that cannot be categorized as an adverse event or protocol deviation will be reviewed by the 
investigators and study MDs to determine the reportability of the problem. 
 
All events will be reported to the IRB, FDA, and other applicable reviewing committees per the 
policies, regulations, and/or guidelines of these entities.  If any of the events require revisions to 
the consent form(s) and/ or the protocol, amendments will be submitted to IRB prior to 
implementation, with the exception of the implementation of protocol procedures that are 
required to protect human participants.  In the latter case, these protocol revisions will be 
submitted to the IRB for review within 1 to 5 working days after their implementation. 
 
d. Legal risks such as the risks that would be associated with breach of confidentiality. 
 
This study involves questions about drug use and dangerous or illegal behavior, psychiatric 
history. If there is a breach of confidentiality, then there may be a legal risk of release of 
sensitive information. To reduce the likelihood of patient records disclosure we will obtain a 
Certificate of Confidentiality. 
 
e. Financial risks to the participants. 
This study includes healthy volunteers for research and the financial risks are minimal. 
 
 

 
 
 
 
Page 18 of 24 
 
9. 
Benefits 
a. 
Description of the probable benefits for the participant and for society. 
 
There is no direct benefit to the participants from being in this study.  If they participate, 
they may help others in the future. The primary benefit of the proposed research is in the 
knowledge gained regarding the relative biological, subjective and behavioral effects of 
chronic exposure to tobacco and the tobacco abstinence syndrome. Because we anticipate 
relatively minor risks to these tobacco-experienced study participants, we feel that the 
proposed research has a positive risk benefit ratio. 
 
10. 
Payment and Remuneration 
 
a. 
Detail compensation for participants including possible total compensation, proposed bonus, 
and any proposed reductions or penalties for not completing the protocol. 
 
All participants will be compensated $40 for completing the screening visit. Participants will 
be paid in cash for the initial screening procedures. Should participants need to complete an 
additional study visit, such as a second visit to complete additional screening 
procedures/assays, participants would receive $25 for this additional visit, although 
additional visits will likely be rare. 
 
Participant compensation is as detailed in Table 1 below. The balance of the payments for 
study procedures will be made after each study visit. Payments of $50 or greater will be via 
check. Compensation during the 8-day quit attempt is partially contingent on successfully 
providing exhaled breath CO and/or urine cotinine samples indicative of tobacco abstinence 
Participants failing to abstain for 24 hrs prior to the scheduled PET (quit day 1) based on 
targeted CO and cotinine thresholds for these outcomes will be given one additional chance 
to complete PET procedures (i.e., these individuals would be invited to re-start their quit 
attempt from day 1 during a subsequent week) and will also be compensated $25for a visit 
in which they provide a sample over the specified CO and urine cotinine thresholds. After 
the PET, study participants will continue in the study whether or not they maintain CO and 
cotinine criteria levels, and are eligible for the bonus ($50) for study completion.  
 
 
Procedures for cigarette smokers:   
 
 
 
 
 
 
 
 
 
 
STUDY VISITS 
Procedure 
Payment 
Incentive bonus  
(not smoking) 
Maximum visit 
payment 
Visit 1 Smoking as Usual  
Assessments 
$40  
not applicable  
$125  
  
MRI 
$85  
  
 
 
 
Visit 2 - Practice Quit Day 1 
Assessments 
$40  
$75  
$315  
  
PET scan  
$200  
  
 
 
 
Visit 3- Practice Quit Day 8 
Assessments 
$40  
$75  
$115  
  
 
 
 

 
 
 
 
Page 19 of 24 
 
Completion Bonus  
  
  
  
$50  
  
 
 
 
Subtotal 
  
  
 
$605  
  
 
 
 
Typical Total compensation with Screening visit 
  
$645  
Max Compensation with extra visit 
$25  
 
$670  
 
Participants who drop out or do not complete all procedures will be paid the money earned for 
completed procedures prior to drop out, but will forfeit future possible earnings. If study 
investigators decide that it is not safe for a participant to continue the study, or are excluded after 
the ECG or MRI incidental findings, participants will be paid the money earned for completed 
procedures. 
 
 
 
11. 
Costs 
a. 
Detail costs of study procedure(s) or drug (s) or substance(s) to participants and identify 
who will pay for them. 
 
Participants are not responsible for the cost of the study procedures or drugs. The only direct 
costs to the participants will be their transportation to and from our research facilities for 
study visits. That cost has been factored into the compensation for participating. 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
 
Page 20 of 24 
 
 
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Hughes JR. Effects of abstinence from tobacco: valid symptoms and time course. Nicotine & 
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