Clinical trial NCT05522673
Conditions: Depression
Keywords: PET Imaging Inflammation Ketamine Depression
Sponsor: National Institute of Mental Health (NIMH)
Start date: 2023-02-08; Completion date: 2024-01-30
Enrollment: 1 participants; Allocation: NA; Intervention model: SINGLE_GROUP

Brief summary:
Background:

Major depressive disorder (MDD) may have many underlying causes. One theory is that brain cells with low levels of a molecule called cyclic AMP (cAMP) may cause depression. A drug called ketamine may increase the levels of cAMP in a person's brain cells.

Objective:

To find out if administering ketamine to people with depression affects cAMP levels in their brains.

Eligibility:

People aged 18 to 70 with MDD who are enrolled in another NIH study that uses ketamine.

Design:

Participants will visit the NIH clinic 5 times in up to 6 weeks. Some of the visits may be spread out over more than 1 day.

Participants will be screened. They will have a physical exam with blood and urine tests. They will have a test of their heart function. They will have a psychiatric evaluation. They will answer questions about their family history and mental health.

Participants will have a positron emission tomography (PET) scan. A small amount of a radioactive drug will be injected into a vein in their arm. Participants will lie on a bed that slides in and out of a doughnut-shaped machine that records images of their brains. They will have their heads in a holder to prevent movement. Each scan will last up to 2 hours.

After their first PET scan, participants will receive ketamine in a different study they are enrolled in. Then they will come back for another PET scan with the radioactive drug.

Participants will also have another scan called an MRI. They will lie on a table that slides into a metal tube. They will lie still for up to an hour....

Detailed description:
Study Description:

This study will test the effects of ketamine infusion on the cAMP system in human brain to determine if ketamine mediates its antidepressant effects at least in part due to modulation of cAMP signaling.

Objectives:

Primary Objective: To determine if ketamine infusions in depression causes increases in cAMP signaling as measured by \[11C\](R)-rolipram binding.

Secondary Objectives: To determine if increases in \[11C\](R)-rolipram correlate with symptomatic improvement in major depressive symptoms.

Endpoints:

Primary Endpoint: measurement of PDE4 density (volume of distribution VT) in brains of individuals with major depressive disorder (MDD) before and after administration of ketamine.

Secondary Endpoints: Clinical rating scales of depression, including MADRS, HAM-D.

Arms: arm 1: Participants with major depressive disorder received 20 mCi of \[11C\](R)-rolipram intravenously for two PET scans, prior to and after ketamine infusion as well as brain MRI
Interventions: intervention 1: 11(R)-rolipram
Intervention descriptions: intervention 1: Injected IV followed by PET scanning

Protocol documents:
Prot_SAP_000.pdf: 
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Abbreviated Title: cAMP Signaling Affected by Ketamine 
NIH IRB #: 000824  
Version Date: 09/11/2023 
Title: [11C]-(R)-Rolipram to Measure cAMP Signaling Before and After Ketamine 
 
 
 
 
NIH Principal Investigator: Robert Innis, M.D., Ph.D. 
Molecular Imaging Branch 
National Institute of Mental Health 
Building 10, Rm B1D43 
9000 Rockville Pike 
Bethesda, MD 20892 
Phone : 301.594.1368 
E-mail: robert.innis@nih.gov 
 
 
Investigational Agents  
Drug Name: 
[11C](R)-rolipram 
IND Number: 
73149 
Sponsor: 
NIMH IRP 
Manufacturer: 
NIMH IRP 
 
 
 


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TABLE OF CONTENTS _Toc96953748 
STATEMENT OF COMPLIANCE ............................................................................................ 4 
1 
PROTOCOL SUMMARY ................................................................................................... 5 
1.1 
Synopsis .................................................................................................................... 5 
1.2 
Schema ...................................................................................................................... 6 
1.3 
Schedule of Activities (SOA) ................................................................................... 7 
2 
INTRODUCTION.............................................................................................................. 8 
2.1 
Study Rationale ......................................................................................................... 8 
2.2 
Background ............................................................................................................... 9 
2.3 
Risk/Benefit Assessment ........................................................................................ 14 
3 
OBJECTIVES AND ENDPOINTS ................................................................................... 16 
4 
STUDY DESIGN............................................................................................................... 16 
4.1 
Overall Design ........................................................................................................ 16 
4.2 
Scientific Rationale for Study Design..................................................................... 17 
4.3 
Justification for Dose .............................................................................................. 17 
5 
STUDY POPULATION .................................................................................................... 17 
5.1 
Inclusion Criteria .................................................................................................... 17 
5.2 
Exclusion Criteria ................................................................................................... 18 
5.3 
Inclusion of Vulnerable Participants ....................................................................... 19 
5.4 
Lifestyle Considerations ......................................................................................... 19 
5.5 
Screen Failures ........................................................................................................ 20 
5.6 
Strategies for Recruitment and Retention ............................................................... 20 
6 
STUDY INTERVENTION ................................................................................................ 21 
6.1 
Study Interventions(s) Administration .................................................................... 21 
6.2 
Preparation/Handling/Storage/Accountability ........................................................ 22 
6.3 
Measures to Minimize Bias: Randomization and Blinding .................................... 23 
6.4 
Study Intervention Compliance .............................................................................. 23 
6.5 
Concomitant Therapy.............................................................................................. 23 
7 
STUDY INTERVENTION DISCONTINUATION AND PARTICIPANT 
DISCONTINUATION/WITHDRAWAL................................................................................. 23 
7.1 
Discontinuation of Study Intervention .................................................................... 23 
7.2 
Participant Discontinuation/Withdrawal from the Study ........................................ 24 


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7.3 
Lost to Follow-up .................................................................................................... 24 
8 
STUDY ASSESSMENTS AND PROCEDURES ............................................................. 24 
8.1 
Screening Procedures .............................................................................................. 24 
8.2 
Study Evaluations & Procedures ............................................................................ 25 
8.3 
Safety and Other Assessments ................................................................................ 27 
8.4 
Adverse Events and Serious Adverse Events ......................................................... 28 
8.5 
Unanticipated Problems .......................................................................................... 31 
9 
STATISTICAL CONSIDERATIONS............................................................................... 32 
9.1 
Statistical Hypothesis .............................................................................................. 32 
9.2 
Sample Size Determination..................................................................................... 32 
9.3 
Populations for Analyses ........................................................................................ 32 
9.4 
Statistical Analyses ................................................................................................. 32 
10 
REGULATORY AND OPERATIONAL CONSIDERATIONS .................................. 33 
10.1 
Informed Consent Process ...................................................................................... 33 
10.2 
Study Discontinuation and Closure ........................................................................ 34 
10.3 
Confidentiality and Privacy .................................................................................... 35 
10.4 
Future use of Stored Specimens and Data .............................................................. 35 
10.5 
Safety Oversight...................................................................................................... 36 
10.6 
Clinical Monitoring ................................................................................................. 36 
10.7 
Quality Assurance and Quality Control .................................................................. 36 
10.8 
Data Handling and Record Keeping ....................................................................... 37 
10.9 
Protocol Deviations and Non-Compliance ............................................................. 37 
10.10 
Publication and Data Sharing Policy ...................................................................... 38 
10.11 
Conflict of Interest Policy ....................................................................................... 38 
11 
ABBREVIATIONS ........................................................................................................ 39 
12 
REFERENCES ............................................................................................................... 41 
 
 
 


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STATEMENT OF COMPLIANCE 
The trial will be carried out in accordance with International Conference on Harmonisation Good 
Clinical Practice (ICH GCP) and the following:  
• United States (US) Code of Federal Regulations (CFR) applicable to clinical studies (45 
CFR Part 46, 21 CFR Part 50, 21 CFR Part 56, 21 CFR Part 312, and/or 21 CFR Part 812)  
National Institutes of Health (NIH)-funded investigators and clinical trial site staff who are 
responsible for the conduct, management, or oversight of NIH-funded clinical trials have 
completed Human Subjects Protection and ICH GCP Training. 
The protocol, informed consent form(s), recruitment materials, and all participant materials will 
be submitted to the Institutional Review Board (IRB) for review and approval.  Approval of both 
the protocol and the consent form must be obtained before any participant is enrolled.  Any 
amendment to the protocol will require review and approval by the IRB before the changes are 
implemented to the study.  In addition, all changes to the consent form will be IRB-approved; an 
IRB determination will be made regarding whether a new consent needs to be obtained from 
participants who provided consent, using a previously approved consent form. 
 
 


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1 
PROTOCOL SUMMARY 
1.1 
Synopsis 
Title: 
[11C]-(R)-Rolipram to Measure cAMP Signaling Before and After 
Ketamine 
Study Description: 
This study will test the effects of ketamine infusion on the cAMP 
system in human brain to determine if ketamine mediates its 
antidepressant effects at least in part due to modulation of cAMP 
signaling. 
Objectives: 
 
Primary Objective: To determine if ketamine infusions in depression 
causes increases in cAMP signaling as measured by [11C](R)-
rolipram binding.  
Secondary Objectives: To determine if increases in [11C](R)-rolipram 
correlate with symptomatic improvement in major depressive 
symptoms. 
Endpoints: 
Primary Endpoint: measurement of PDE4 density (volume of 
distribution VT) in brains of individuals with major depressive 
disorder (MDD) before and after administration of ketamine. 
Secondary Endpoints: Clinical rating scales of depression, including 
MADRS, HAM-D. 
Study Population: 
35 inpatient participants with major depressive disorder eligible for 
ketamine administration and enrolled in protocols 19-M-0107 
“Ketamine and AMPA”, 17-M-0060 “Neuropharmacology of 
Ketamine” or 15-M-0188 “Neurobiology of Suicide.”. Participants 
may be male or female. They must be between 18 and 70 years old. 
MDD participants must be in good medical health and provide 
informed consent. 
Phase: 
N/A 
 
 
Description of 
Sites/Facilities 
Enrolling 
Participants: 
Screening, PET imaging and ketamine infusion will be performed at 
the NIH Clinical Center.  
Description of Study 
Intervention: 
Participants will be intravenously injected with about 20 mCi of 
[11C](R)-rolipram for 2 PET scans, prior to and after ketamine 
infusion. All participants will have radial artery catheters inserted for 
each scan to measure radioligand concentration, as well as a brain 
MRI to provide anatomical orientation for PET studies. 
Study Duration: 
36 months 
Participant 
Duration: 
Approximately six weeks depending on participant’s availability and 
investigators’ overall access to MRI and PET cameras.  
 
 


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1.2 
Schema 
 
 
Prior to  
Enrollment 
 
 
 
 
 
 
 
 
 
 
 
 
 
Visit 1 
Time Point  
 
  
 
 
Visit 2 
 
 
 
 
Visit 3 
 
 
 
 
 
Visit 4 
 
 
 
 
 
 
Visit 2-5 
 
 
* One brain MRI will be performed per participant and will be scheduled either on any visit that 
is logistically appropriate or on the 5th visit if it’s the last thing needed.  
 
Consent, Psychiatric Evaluation, History, Physical Exam, Screening Labs, EKG, 
Inclusion/Exclusion Criteria 
Ketamine infusions will be performed under protocols #19-M-0107 “Ketamine and 
AMPA”, 17-M-0060 “Neuropharmacology of Ketamine” or 
15-M-0188 “Neurobiology of Suicide” 
IV-placement, , Arterial Line,  
PET scan with [11C](R)-rolipram, prior to ketamine infusion, clinical rating scales, 
follow-up phone call 
IV-placement, Arterial Line,  
PET scan with [11C](R)-rolipram, after ketamine infusion, clinical rating scales,  follow-up 
phone call 
Brain MRI* 
Phone screening, assessment of medical records and screened under protocol #01M0254 
“The Evaluation of Patients with Mood and Anxiety Disorders and Healthy Participants” 
Subjects will be screened through one of the three ketamine studies (#19-M-0107 
“Ketamine and AMPA”, 17-M-0060 “Neuropharmacology of Ketamine” or 15-M-0188 
“Neurobiology of Suicide”). 
Experimental Therapeutics and Pathophysiology Branch (ETPB) AIs will refer potential 
participants to this protocol for review of eligibility. Subjects who qualify are contacted and 
offered enrollment into this study. 


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1.3 
 
Schedule of Activities (SOA) 
The study will require one to five visits: 1) Initial evaluation, 2) Pre-ketamine PET scan, 3) 
ketamine infusions, 4) post-ketamine PET scan, and 5) brain MRI.  
The screening evaluations during the initial visit will take 4-6 hours and will typically be 
performed in one day. However, these screening evaluations may be performed on different days 
depending on the preference of the participant and staff availability. Study procedures may take 
up to 6 weeks, depending on availability of PET scans and schedule of events of other protocols 
they may be included on.  During the first visit, the participant will give informed consent and 
complete the screening, which includes a history and physical exam, as well as a psychiatric 
evaluation.  The screening evaluation will include screening labs, EKG, clinical brain MRI 
(approx. one hour) and will typically be done on the same day. The baseline PET scan will occur 
prior to the initial inpatient ketamine infusion. The two PET scans will occur within an interval 
<6 weeks, with the post-ketamine infusion scan to occur within 1 week of ketamine infusion. 
  
 
1st  
Visit 
2nd 
 Visit 
3rd  
Visit 
4th  
Visit 
5th  
Visit 
Informed consent and 
Psychiatric evaluation 
 
X 
 
 
 
 
History and physical exam 
X 
 
 
 
 
Screening labs* 
X 
X 
 
 
 
Clinical rating scales 
X 
 
X 
 
Research blood draw 
X 
 
 
 
 
EKG 
X 
 
Ketamine Infusion(s)** 
 
 
X 
 
 
PET Scan 
 
X 
 
X 
 
Brain MRI 
On one of visits 2-5  
*The screening labs are described in Section 5.2, exclusion criterion #1.  
**Ketamine infusion will be performed under protocol #19-M-0107, 17-M-0060 or 15-M-0188. 
 


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2 
INTRODUCTIONStudy Rationale 
Major depressive disorder (MDD) 
(MDD) is a prevalent psychiatric disorder with a lifetime prevalence of 20.6% in the 
United States [4]. It is a major cause of disability worldwide, with suicide being the 10th leading 
cause of death in the United States, the second leading cause of death between the ages of 10 and 
34, and the fourth leading cause of death between the ages of 35 and 44, according to CDC data 
in 2019. Despite decades of rigorous study, no consensus on etiology or molecular 
pathophysiology of MDD exists. Current treatment modalities for MDD include pharmacological 
treatment with antidepressant medications, most of which act to target monoamine levels in the 
synaptic cleft. This increase in monoamines has been shown to occur within hours to days; 
however, symptomatic relief, if any is noted, does not usually manifest until days to weeks after 
compliant medication use. Given the relatively low rates of response and remission of 
monoamine-targeted therapies, as well as discordance between molecular effects and 
symptomatic improvement, alternative frameworks for the physiological underpinnings of MDD 
are needed. One such framework is called the “cAMP theory of depression”, which posits that 
low cAMP signaling predisposes to MDD, and hypothesizes that at least a subgroup of patients 
with MDD present with symptoms due to low cAMP signaling. Targeting the increase of cAMP 
is a major direction in the development of new antidepressants, among which ketamine and its 
metabolites have emerged as effective, rapid-onset treatments for MDD.  
In addition to their effects on monoamine levels, chronic (but not acute) antidepressant 
use has been shown to increase cAMP production ([5, 6], Figure 1). In contrast to the delayed 
effectiveness of other antidepressant drugs, Ketamine produces rapid and robust antidepressant 
effects in depressed patients within hours of administration. Classically known as a 
noncompetitive N-methyl-D-aspartate receptor (NMDAR) antagonist, ketamine and its 
metabolites have been shown to increase cAMP signaling rapidly in glial cell culture models 
([1]), concordant with the observed time-frame of its antidepressant action. We have previously 
shown a global decrease in cAMP signaling in MDD as measured by [11C](R)-rolipram ([7]), and 
further that two-month treatment with antidepressants increased [11C](R)-rolipram binding 
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at least in part via increases in cAMP signaling, and propose to test this hypothesis via [11C](R)-
rolipram binding before and after ketamine treatment.  
2.2 
Background  
Imaging of cAMP: Studies with rolipram 
PDE4 metabolizes and thereby terminates the actions of the second messenger cAMP. 
(Figure 1). Rolipram is a reversible PDE4 inhibitor, and we believe that binding of [11C](R)-
rolipram is positively correlated with cAMP signaling. Please note that this interpretation is 
opposite to what most would initially think, which is that increased PDE4 activity would 
metabolize cAMP and therefore be associated with decreased cAMP signaling. A series of rat 
studies (reviewed below) confirmed a negative feedback system mediated by protein kinase A 
(PKA). Within this system, cAMP stimulates PKA, which phosphorylates PDE4, which 
increases enzyme activity about 10-fold and increases the affinity of rolipram for PDE4 by about 
10-fold. Therefore, the in vivo binding of [11C](R)-rolipram largely reflects the activated 
(phosphorylated) form of PDE4, which is mediated by cAMP and PKA (Figure 2).  
Figure 1. Chronic (but not acute) antidepressant treatments upregulated the cAMP 
cascade. Although serotonin (5HT) and norepinephrine (NE) are immediately increased by 
AD treatment (black arrows), the therapeutic response takes weeks or months. However, 
portions of the cAMP signaling, marked with the red arrows, are upregulated over weeks or 
months, as well, and may mediate the therapeutic response. In turn, cAMP upregulates both 
Phosphodiesterase 4 & PKA – increasing production of both 5'-AMP & CREB. Within the 
nucleus, CREB, a responsive transcription factor, upregulates BDNF gene expression which 
then promotes neuronal plasticity & cell survival, and is thought to mediate antidepressant 
effects. (Modified from [3]) 


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We found that [11C](R)-rolipram 
binding was globally decreased in 
unmedicated MDD subjects experiencing a 
major depressive episode compared to 
controls [7]}. This result is consistent with the 
‘cAMP theory of depression’, which posits 
that low cAMP signaling causes at least some 
symptoms of depression. As a follow-up, we 
found that, in MDD subjects, two months of 
treatment with an SSRI increased (i.e., 
normalized) [11C](R)-rolipram binding 
compared to pretreatment values [6]. This 
result is consistent with the ‘cAMP theory of 
the mechanism of antidepressant action’—
namely, that chronic, but not acute, treatment 
with conventional antidepressants increases 
the cAMP signaling cascade, including PDE4. 
PDE4 is an excellent target in this regard, as 
the cAMP theory of depression suggests that 
inhibiting this enzyme should have antidepressant effects. In fact, Pfizer tested rolipram as an 
antidepressant in the early 1990s. The results were inconclusive, but some evidence of rapid 
antidepressant effects was noted. However, development of this agent was stopped early because 
of nausea and vomiting, possibly associated with PDE4D inhibition. Interestingly, ketamine has 
also been associated with nausea, although it is generally well-tolerated. 
 
In Vivo Density, Affinity, and Phosphorylation Status of PDE4. Our initial experiments 
sought to measure both the in vivo and in vitro binding site density and radioligand affinity of 
[11C](R)-rolipram in rat brain [8]. We found that in vivo affinity was five-fold greater than in 
vitro affinity, although density was similar in both conditions. The finding was consistent with 
the rapid dephosphorylation of PDE4 after anoxia and death. Thus, our results implied that if we 
wished to measure PDE4 in its activated/phosphorylated form, we could not use postmortem 
tissue—such studies had to be performed in living subjects. 
Our next study [9]} examined the effects of PKA modulators in conscious rats on 
[11C](R)-rolipram binding compared to the much less active enantiomer [11C](S)-rolipram. Two 
drugs were studied. In the first study, the cAMP analogue db-cAMP was used to activate PDE4, 
thus increasing activity of the cAMP-dependent PKA. PKA then phosphorylated the PDE4 
enzyme and increased PDE4 activity. We also studied Rp-cAMP, a PKA inhibitor that directly 
inhibited PKA function, thereby decreasing PDE4 activity. Unilateral injection of the PKA 
activator (db-cAMP) and the PKA inhibitor (Rp-cAMP) into the striatum significantly increased 
and decreased [11C](R)-rolipram binding, respectively. These effects were not caused by changes 
in blood flow or delivery of radioligand to brain because these agents did not affect [11C](S)-
rolipram binding. The results demonstrated that [11C](R)-rolipram binding reflected the activated 
phosphorylated form of PDE4 and, more generally, supported the interpretation that increased 
[11C](R)-rolipram binding was associated with increased cAMP signaling. 
Figure 2. cAMP activates protein kinase A 
(PKA), which phosphorylates and activates 
the enzyme phosphodiesterase4 (PDE4) and 
increases affinity of radioligand binding of 
[11C](R)-rolipram by about 10-fold. This 
process confirms a negative feedback loop 
between cAMP and PDE4. 


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PDE4 Binding in MDD. Based on these preclinical findings, we hypothesized that 
[11C](R)-rolipram PET in humans would provide a unique in vivo measure of PDE4 density and 
affinity not observable in postmortem tissue. Expanding our work, we sought to quantify the 
binding of [11C](R)-rolipram as an indirect measure of this enzyme’s activity in the brain of 
individuals with MDD compared with healthy controls [7]. This work was particularly important 
because animal studies had suggested that upregulation of the cAMP cascade, including PDE4, 
was a mechanism of action common to several antidepressant treatments (reviewed in [10]). To 
avoid the misleading results that can be obtained from small sample sizes, we scanned a total of 
44 unmedicated, moderately depressed patients with MDD and 35 age- and gender-matched 
healthy controls, which is about twice the size of most PET studies in psychiatry. Notably, about 
half the patients were treatment-naïve. [11C](R)-rolipram binding in brain was measured using 
arterial [11C](R)-rolipram levels to correct for the influence of cerebral blood flow. MDD 
subjects showed a widespread, 18% reduction in [11C](R)-rolipram binding (P=0.0001) that was 
not caused by different gray matter volumes. Decreased [11C](R)-rolipram binding of a similar 
magnitude was observed in most brain areas. These results were the first to demonstrate that 
brain levels of PDE4, a critical enzyme that regulates cAMP, are decreased in unmedicated 
individuals with MDD in vivo. Furthermore, the results are in line with human postmortem and 
rodent studies demonstrating downregulation of the cAMP cascade in MDD, and support the 
hypothesis that PDE4 inhibitors—which increase cAMP cascade activity—may have 
antidepressant effects, as demonstrated in animal experiments.  
Effect of Chronic Antidepressants on PDE4 Binding. Building on this work, and in 
collaboration with Dr. Carlos Zarate (NIMH), we sought to determine whether antidepressant 
treatment upregulates PDE4 
in humans as it does in 
animals. Of the 44 
unmedicated MDD patients 
described above, 23 had a 
follow-up [11C](R)-rolipram 
scan after approximately 
eight weeks of treatment 
with an SSRI [6], which 
significantly increased 
[11C](R)-rolipram binding 
(12%, p<0.001), with 
significantly greater 
increases observed in older 
patients (p<0.0001), 
although rolipram binding 
did not correlate with 
severity of baseline 
symptoms, and increased 
[11C](R)-rolipram binding 
during treatment did not 
correlate with symptom 
improvement. Taken 
Fig. 3. [11C](R)-rolipram signal coincides [18F]NaF in 
McCune Albright Syndrome, demonstrating ability of 
rolipram to measure cAMP signaling. Maximum intensity 
projected images of [11C](R)-rolipram of a healthy control and 
of a patient with MAS, and [18F]NaF bone scan from the same 
patient. The MAS patient shows increased [11C](R)-rolipram 
binding compared to the healthy control, which coincides with 
areas of fibrous dysplasia as shown on the [18F]NaF bone scan. 
[2] 


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together, these results elucidate two important and related points. First, the cAMP cascade—as 
indirectly measured with PDE4 binding—was downregulated in unmedicated patients with 
MDD. Second, antidepressant treatment normalized this [11C](R)-rolipram downregulation. The 
lack of correlation between PDE4 binding and depressive symptoms could reflect the 
heterogeneity of the disease and/or the heterogeneity of the target, given that PDE4 has four 
subtypes. Nevertheless, these results suggest that PDE4 inhibition, perhaps via subtype-selective 
agents, might again be assessed for efficacy in MDD; the results also broadly support the cAMP 
theory of depression and of antidepressant action. Our goal in this project is to build on this work 
to determine if ketamine also targets cAMP signaling similar to SSRI treatment, and if these 
results correlate to clinical improvements.  
Imaging PDE4 with [11C](R)-rolipram in McCune Albright Syndrome Patients. Given the 
less-well-known connection between MDD and cAMP signaling, we decided to confirm our 
method of testing of [11C](R)-rolipram to image PDE4 in McCune Albright Syndrome (MAS), a 
syndrome characterized by mosaicism arising from mutations in the GNAS gene, which activates 
adenylyl cyclase, and directly generating cAMP and causing fibrous dysplasia which can be 
measured by [18F]NaF [2]. Building on our previous work that developed and tested the ability of 
[11C](R)-rolipram to image PDE4, we used [11C](R)-rolipram to measure PDE4 binding in 
patients with MAS and performed both brain and whole-body scans in patients with MAS and 
healthy controls. The whole-body scans compared uptake between areas of fibrous dysplasia and 
unaffected bones. [11C](R)-rolipram uptake in peripheral organs was also compared between 
subjects with MAS and healthy controls. The latter comparison was important because, in MAS, 
some tissues may contain GNAS mutations even in the absence of obvious structural changes. 
 Brain scans with [11C](R)-rolipram and full arterial sampling were performed on 7 
healthy controls and 3 individuals with MAS. [11C](R)-rolipram binding was increased in 
dysplastic bone but not in other peripheral organs, as shown by whole-body scans in individuals 
with MAS compared to healthy controls (Fig. 1) Areas of skeletal uptake seen on the PDE4 
whole-body images coincided with areas of uptake seen in images from [18F]NaF PET/CT scans. 
In addition, [11C](R)-rolipram binding was not increased in the brains of individuals with MAS 
compared with healthy controls, and mosaicism (i.e., small areas of increased binding) was not 
apparent on visible inspection of the images. These results are the first confirmation in humans 
that increased PDE4 binding is associated with increased cAMP signaling, consistent with our 
interpretation of animal studies of [11C](R)-rolipram. In addition, this study supported the utility 
of such PET scans to indirectly measure altered cAMP signaling in other human diseases, 
including major depressive disorder, if the abnormality extends to adequately sized regions of the 
target organ. 
Evidence that ketamine mediates its antidepressant effects in part via the cAMP system 
 
As stated previously, ketamine has been demonstrated to have rapid antidepressant 
effects that contrast with monoamine-associated therapies such as SSRIs. While classically 
ketamine is considered an NMDAR-antagonist, and has some known associations with 
glutamatergic signaling, there is also evidence that ketamine’s antidepressant effect may be 
independent of NMDAR ([1],[11]). First, other NMDAR antagonists, such as memantine, have 
failed to consistently demonstrate the rapid and robust antidepressant effect of ketamine, despite 
ostensibly having a similar mechanism of action ([12]). Further, while generally ketamine 
treatments include a racemic mixture of both (R)- and (S)-ketamine (arketamine and esketamine 


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hereafter), there is a significant difference between affinities of these enantiomers for the 
NMDAR, with arketamine demonstrating a Ki of 1.4 uM, compared to esketamine at Ki of 0.3 
uM. While esketamine is now Food and Drug Administration (FDA) approved for the treatment 
of depression, arketamine has been demonstrated to have a greater potency for antidepressant 
effects in rodent models compared to esketamine (reviewed in [11]).  
 
Ketamine has been demonstrated to increase proliferation in neuronal progenitor cells in 
an NMDA-independent manner, while also increasing cAMP signaling within 15 minutes ([13]). 
Wray et al [1] also demonstrated that treatment of C6 glioma cells with ketamine led to increased 
cAMP accumulation, as well as subsequent pCREB and BDNF (Figure 4). Phosphorylated 
CREB (pCREB) translocates to the nucleus where it acts as a transcription factor for genes 
involved in growth and survival, neuroprotection, and synaptic plasticity, perhaps in part due to 
downstream effects of BDNF transcription [14],[15]. CREB is both upregulated and 
phosphorylated at Ser-133 after chronic antidepressant treatment in animals and cultured cells 
[15]. This effect was noted to be mediated by a ketamine-induced association between Gαs with 
adenylyl cyclase, a mechanism shared by prolonged antidepressant treatment[16]. 
  
 
Given a proposed mechanism demonstrated in cell culture models, as well as the 
clinically relevant use of ketamine in treatment-resistant patients with MDD, our proposed study 
will correlate changes in the cAMP signaling system in human patients treated with ketamine to 
determine 1) if decreased [11C](R)-rolipram binding is corrected acutely by ketamine treatment, 
and 2) if any such correction will be correlated to clinical response.  
 
 
 
 
Figure 4. Ketamine treatment increases BDNF in a CREB- and cAMP-dependent 
manner. C9 cells treated with ketamine demonstrate increase levels of active CREB (P-
CREB) in response to acute ketamine infusion, which results in downstream increases in 
BDNF production, an effect that is disrupted by Rp-CAMPS, an inhibitor protein kinases 
downstream of cAMP signaling [1]. 


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2.3 
Risk/Benefit Assessment 
2.3.1 Known Potential Risks 
Risks include those associated with: a) clinical rating scales and psychiatric assessment; 
b) MRI; c) EKG, d) placement of venous and arterial lines; e) arterial blood sampling; f) 
radiation exposure from the radioligand and from the transmission scan; g) PET scanning. 
2.3.1.1 Risks of Clinical Rating Scales and Psychiatric Assessment 
No discomfort is expected to occur during clinical interviews or psychological 
assessments, other than the potential emotional stress caused by discussing difficult psychiatric 
topics. 
2.3.1.2 MRI 
People are at risk for injury from the MRI magnet if they have pacemakers or other 
implanted electrical devices, brain stimulators, some types of dental implants, aneurysm clips 
(metal clips on the wall of a large artery), metallic prostheses (including metal pins and rods, 
heart valves, and cochlear implants), permanent eyeliner, an implanted delivery pump, or 
shrapnel fragments. Welders and metal workers are also at risk for injury because of possible 
small metal fragments in the eye of which they may be unaware. Participants will be screened 
again for these conditions before having any scan and will not receive an MRI scan if they have 
any contraindications.  
It is not known whether MRI is completely safe for a developing fetus. Therefore, all 
women of childbearing potential will have a urine pregnancy test performed no more than 24 
hours before each MRI scan. The scan will not be done if the pregnancy test is positive.  
People with fear of confined spaces may become anxious during an MRI. Those with 
back problems may have back pain or discomfort from lying in the scanner. The noise from the 
scanner is loud enough to damage hearing, especially in people who already have hearing loss. 
Everyone having a research MRI scan will be fitted with hearing protection. Participants will be 
asked to complete an MRI screening form for each MRI scan they have. There are no known 
long-term risks associated with MRI scans. 
2.3.1.3 EKG 
The patient may feel uncomfortable while the electrodes are attached to the chest. The 
conductive gel sometimes causes some mild irritation. 
2.3.1.4 Placement of Venous and/or Arterial Line 
Venous catheter insertion can be associated with discomfort, bruising, infection, or clot 
formation. Using proper placement techniques will minimize these risks. In case of tracer 
extravasation, we will stop the study, remove the venous line from the arm, and apply cold to the 
site. Arterial catheterization is a generally safe and reliable method of obtaining arterial blood 
samples [28, 29]. Placement of a radial arterial catheter may cause bruising or infection. There is 
also a risk of occlusion and microemboli. Over 3,000 arterial catheters have been placed to date 
in the PET Department. Of these, only two complications requiring physician’s care arose. In the 
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repaired surgically. In the second case, a radial artery thrombosis developed 28 days later, which 
was also successfully repaired surgically. 
2.3.1.5 Blood Sampling 
Participants may have arterial or venous blood sampling. The total amount of blood drawn 
shall not exceed 10.5 mL/kg or 550 mL, whichever is smaller, over any eight-week period. 
Blood sampling may lead to the formation of small subcutaneous hematomas caused by blood 
leaking from a punctured blood vessel. Such hematomas cause only minor discomfort. They are 
not dangerous and require no treatment other than reassuring the participant. There is also a 
small risk of infection at the site of the needle puncture, which can be readily treated with 
antibiotic therapy. We will ask participants not to donate blood within eight weeks before the 
study and for eight weeks following the study.   
2.3.1.6 Radiation Exposure Risks 
Radiation exposure in this protocol will be from [11C](R)-rolipram and the associated 
transmission scans.  
The radiation exposure (rem) from two injections of [11C](R)-rolipram, 20 mCi each, 
which is a typical dose for brain imaging, is: effective dose (0.8). Gallbladder (1.6), lungs (2.2), 
and liver (1.9) are the three organs with the highest levels [30]. 
With regard to exposure from the transmission scan, the PET Department recently 
implemented Dr. Innis’s suggestion to decrease the current (amperage) and, thus, overall 
radiation from the CT scan. We do not need a high resolution (high current) image for 
attenuation correction; a low-resolution scan, like that obtained from a line source, is perfectly 
adequate to correct attenuation in the PET emission scan. With the lowered current, the exposure 
to the lens of the eye is now 0.26 rem, about one-third of the previous value.  
We routinely include the dose from two transmission scans for each PET scan in the 
event that it must be repeated in any given participant. Therefore, four CT scans might be 
necessary. The effective dose for four head transmission scans from a PET/CT is ~ 0.08 rem. 
Thus, the maximum total effective dose in each [11C](R)-rolipram PET scan is 0.44 rem, and for 
the whole study it would be 0.88 rem. These estimated annual effective doses are well below the 
limit of 5 rem per year established by the NIH’s Radiation Safety Committee. All participants 
will be asked about any prior research participation involving radiation exposure so that the total 
exposure, in combination with the present study, will not exceed an effective dose of 5 rem per 
year. 
2.3.1.7 PET Scan 
PET scans, which detect injected radioactivity within the body, are not associated with 
any known physical hazards to the participant lying on the table. We routinely use a series of 
procedures to minimize the risk of discomfort during scanning sessions. The procedures are 
conducted in the presence of trained health professionals to whom participants will have ready 
access should they experience any problems. Participants can communicate with the trained 
health professionals while in the scanner and can be removed from the scanner and withdraw 
from the study at any time if they wish to do so. Participants can also request that the operator 
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2.3.2 Known Potential Benefits 
This study offers no direct benefits to the participants related to the PET scans but will 
likely provide fundamental knowledge regarding the mechanism of action of ketamine in the 
treatment of depression.  
2.3.3 Assessment of Potential Risks and Benefits 
If the results are positive, PET imaging with [11C](R)-rolipram may be used to explore 
the pathophysiological role of cAMP in depression as well as shed light on the mechanism of 
action of ketamine. This valuable information may then help guide future trials with anti-
depressant drugs, a benefit to future patients that justifies the risks to the current participants. 
With regard to how the study design sought to minimize risks, please see each risk listed 
above (Section 2.3). 
3 
OBJECTIVES AND ENDPOINTS 
4 
STUDY DESIGN 
4.1 
Overall Design 
• Site:  This single-site study will be conducted at the NIH Clinical Center. 
• Hypothesis: We hypothesize that PDE4 levels as quantified by [11C](R)-rolipram in 
the brains of subjects suffering from a major depressive episode will be increased 
with ketamine administration, and that these levels will correlate with clinical rating 
scales. 
• Type of Design: MDD participants will be studied with [11C](R)-rolipram prior to 
and after ketamine infusion. 
Objectives 
Endpoints 
Justification for Endpoints 
Primary 
 
 
Measurement of cAMP 
signaling via [11C](R)-
rolipram density 
(distribution volume VT) 
in the brains of 
individuals with MDD 
before and after 
ketamine infusion 
Distribution volume VT of 
[11C](R)-rolipram pre- and post-
ketamine scan 
Change in VT of [11C](R)-
rolipram is a surrogate marker 
for cAMP signaling, a proposed 
mechanism for ketamine’s 
mechanism of action 
Secondary/Exploratory  
 
1) The relationship 
between clinical rating 
scales and PDE4B 
binding 
1) Distribution volume VT    
 
 
 
2) Clinical rating scales  
 Correlation between VT and 
clinical ratings  


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• Study Groups: Individuals with MDD 
• Study intervention: Two PET scans with [11C](R)-rolipram and MRI of brain. 
• Interim Analysis:  None. 
• Stratifications:  None. 
4.2 
Scientific Rationale for Study Design 
This study is exploratory and seeks to gather information that would be useful for 
designing a larger follow-up study. 
4.3 
Justification for Dose 
Previous studies with [11C](R)-rolipram used a dose of 20 mCi, which is enough to measure 
both radioactivity in brain with PET and the concentration of parent radioligand in arterial 
plasma.  
5 
STUDY POPULATION 
5.1 
Inclusion Criteria 
Patients: In order to be eligible for this study, MDD participants must meet all of the 
following criteria: 
1. Aged 18 to 70 years old. 
2. Female participants of childbearing potential must be using a medically acceptable means 
of contraception. 
3. Participants must be in good general health as evidenced by medical history and physical 
examination. 
4. Each participant must have a level of understanding sufficient to agree to all required 
tests and examinations and sign an informed consent document. 
5. All participants must have undergone a screening assessment under protocol 01-M-0254, 
“The Evaluation of Patients with Mood and Anxiety Disorders and Healthy Participants”. 
6. Participants must be enrolled in the ketamine arms of protocols 19-M-0107 “Ketamine 
and AMPA”, 17-M-0060 “Neuropharmacology of Ketamine”, or 15-M-0188 
“Neurobiology of Suicide”. 
7. Participants must fulfill DSM-5 criteria for major depression (MDD) without psychotic 
features, as based on clinical assessment and structured diagnostic interview (SCID-P). 
8. Participants must have an initial score on the MADRS ≥ 18 or HAM-D ≥ 15 within two 
weeks of study entry. 
9. Participants with stable medical conditions as assessed by their primary care provider 
(PCP) and/or in-house clinician are permitted to join the study. 
10. Patients must qualify for ketamine administration, usually defined as lack of response to 
two adequate lifetime antidepressant trials, with [at least] one in the current major 
depressive episode, operationally defined using the Antidepressant Treatment History 
Form (ATHF); a failed adequate trial of ECT [or TMS] would count as an adequate 
antidepressant trial. 
11. Participants must have their radial artery pulse checked for the presence of adequate ulnar 
collateral flow and the absence of any metal or foreign objects in both wrists. 
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5.2 
Exclusion Criteria 
Participants with MDD who meet any of the following criteria will be excluded from 
participation in this study: 
1. Clinically significant abnormalities on EKG or laboratory testing. This includes CBC, 
acute care panel (Na, K, Cl, CO2, creatinine, glucose, urea nitrogen); prothrombin and 
partial prothrombin tests, the PT/PTT is optional for those without history of coagulation 
disorders or those not on anticoagulation. 
2. Current psychotic features, a diagnosis of schizophrenia or any other psychotic disorder 
as defined in the DSM-5. 
3. Participants with a history of DSM-5 substance use disorder (except for caffeine or 
nicotine dependence) within the preceding three months. In addition, participants must 
not have substance use disorder or alcohol use disorder. However, alcohol or cannabis 
use by themselves are not exclusion criteria, unless that use affects the function of daily 
life.  
4. Participants who, in the investigator’s judgment, pose a current serious suicidal or 
homicidal risk.  
5. Participants who have a history of aggressive behavior towards others.  
6. Participants who have an unstable medical condition that, in the opinion of the 
investigators, makes participation unsafe (e.g., an active infection or untreated 
malignancy). 
7. Are unable to travel to the NIH. 
8. Have recent exposure to radiation related to research (e.g., PET from other research) that, 
when combined with this study, would be above the allowable limits. 
9. Have an inability to lie flat and/or lie still on the camera bed for at least two hours, 
including claustrophobia, overweight greater than the maximum for the scanner, and 
uncontrollable behavioral symptoms, which will be screened by an interview with the 
participant during the screening visit.  
10. Are unable to have an MRI scan (e.g., because of pacemakers or other implanted 
electrical devices, brain stimulators, dental implants, aneurysm clips (metal clips on the 
wall of a large artery), metallic prostheses (including metal pins and rods, heart valves, 
and cochlear implants), permanent eyeliner, implanted delivery pumps, shrapnel 
fragments, or metal fragments in the eye. 
11. Be NIMH staff or an NIH employee who is a subordinate/relative/co-worker of the 
investigators. 
12. Pregnancy 
13. HIV infection 
5.2.1 Exclusion of Children 
Because this protocol has more than minimal risk from radiation exposure without 
possibility of direct benefit, inclusion of children is not appropriate. 
 
 


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5.2.2 Exclusion of Pregnant or Breastfeeding Women 
Pregnant women will be excluded because this protocol involves exposure to ionizing 
radiation. Lactating women will be excluded because radioisotopes may be excreted in milk. 
 
5.2.3 Exclusion of Participants who are HIV Positive 
Persons with HIV infection are excluded because HIV infection itself may change cAMP 
signaling. 
5.3 
Inclusion of Vulnerable Participants 
5.3.1 Safeguards for Vulnerable Populations and Sensitive Procedures 
5.3.1.1 Role of the HSPU 
The Human Subjects Protection Unit will monitor the consent process for all MDD participants.  
5.3.2 Participation of NIH Staff or family members of study team members 
NIH staff may be enrolled in this study as the population meets the study entry criteria 
and NIH Policy 404 will be followed.  There will be no direct solicitation of NIH employees, nor 
will they be directly recruited by or through their supervisors or co-workers to participate in this 
study.  Neither participation nor refusal to participate as a subject in the research will have an 
effect, either beneficial or adverse, on the participant’s employment or position at NIH. NIH 
employees must have permission from their supervisor and/or take leave in order to receive 
compensation if participation is during work hours.  Prior to enrollment, the NIH employee will 
be requested to review the Annual Leave Policy for NIH Employees.  Participant confidentiality 
and privacy will strictly be held in trust by the participating investigators, their staff, and the 
sponsor(s).  
Per NIMH Policy, NIMH employees, staff and their immediate family members will be 
excluded from the study due to ethical concerns about confidentiality and conflict of interest.  A 
copy of the NIH Frequently Asked Questions (FAQs) for Staff Who are Considering 
Participation in NIH Research ) will be made available for NIH employees who wish to 
participate in this study.  
This study collects sensitive medical information. Every effort will be made to protect 
participant information, but such information may be available in medical records and may be 
available to authorized users outside of the study team in both an identifiable an unidentifiable 
manner. The PI will train study staff regarding obtaining and handling potentially sensitive and 
private information about co-workers through staff discussions. 
5.4 
Lifestyle Considerations 
During this study, participants will be asked to abstain from strenuous exercise and from 
lifting more than 10 pounds using the affected arm for 48 hours after removal of the arterial line. 
Patients will be asked not to donate blood for 8 weeks before or 8 weeks after PET scans.  
 
 


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5.5 
Screen Failures 
Screen failures are defined as participants who consent/assent to participate in the clinical 
trial but are not subsequently assigned to the study intervention or entered in the study. A 
minimal set of screen failure information is required to ensure transparent reporting of screen 
failure participants, to meet the Consolidated Standards of Reporting Trials (CONSORT) 
publishing requirements, and to respond to queries from regulatory authorities. Minimal 
information includes demographic characteristics, screen failure details, eligibility criteria, and 
any serious adverse event (SAE). 
Individuals who do not meet the criteria for participation in this trial (screen failure) 
because of an exclusion criterion that may resolve by the time of treatment may be rescreened. 
Rescreened participants should be assigned the same participant number as for the initial 
screening. 
5.6 
Strategies for Recruitment and Retention 
Participants will be recruited from protocol #’s 19-M-0107 “Ketamine and AMPA”, 17-M-
0060 “Neuropharmacology of Ketamine” or 15-M-0188 “Neurobiology of Suicide.”   
The protocol and contact information to obtain further details will be listed on 
www.clinicaltrials.gov. 
5.6.1 Costs 
We expect participants to incur no costs for participating in this study. 
5.6.2 Compensation 
Participants will be compensated for time- and research-related inconveniences. 
Reimbursement is based on NIH standards for time devoted to the research project. Participants 
will be paid for each portion of the study they complete whether or not they opt for early 
withdrawal from participation. Without any delay of study procedures or unanticipated 
inconvenience, the total possible compensation for procedures is $730. Participants will also 
receive compensation for time spent at each visit following the structure of $20 for the first hour 
and $10 for each subsequent hour.  If the investigators need to delay study procedures or if 
additional time is need for completion, participants may receive additional compensation in 
accordance with NIH guidelines.   
Participants may receive support for travel, meals, and lodging according to NIH travel 
policy guidelines. Lodging may be provided directly or reimbursed according to NIH guidelines. 
For NIH employees, guidelines per Policy 404 will be followed.  Employees and staff who 
participate during work hours must have permission from their supervisor. NIH employees must 
either participate outside of work hours or take leave in order to receive compensation. 
 
Visit 1 to NIH 
 
Screening 
$50 
Pregnancy test 
$10 
Psychiatric evaluation 
$50 
Visit 2to NIH 
 


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PET scanning 
$150 
Arterial catheter 
$60 
Antecubital venous catheters 
$30 
Pregnancy test 
$10 
Movement restriction 
$10 
Visit to NIH 3 * 
 
N/A 
Visit 4 to NIH 
 
PET scanning 
$150 
Arterial catheter 
$60 
Antecubital venous catheters 
$30 
Pregnancy test 
$10 
Movement restriction 
$10 
Visit 5 to NIH 
 
MRI 
$100 
Total 
$730 
 
*Ketamine infusions will be performed under protocols #19-M-0107 “Ketamine and AMPA”, 17-M-0060 
“Neuropharmacology of Ketamine” or 15-M-0188 “Neurobiology of Suicide 
 
6 
STUDY INTERVENTION 
6.1 
Study Interventions(s) Administration 
6.1.1 Study Intervention Description 
Each participant will receive two injections of [11C](R)-rolipram, prior to and after 
ketamine infusion, and will also receive an MRI. 
6.1.2 Dosing and Administration 
Each participant will be intravenously injected with about 20 mCi of [11C](R)-rolipram 
for each PET scan. The yield of the radioligand synthesis varies such that the available dose may 
be more or less than 20 mCi. By prior agreement with NIH’s Radiation Safety Committee, the 
clinician covering the scan can approve a dose as low as half of the prescribed dose. We expect 
that a dose of about 20 mCi will likely be adequate for all participants per scan. The maximal 
dose will provide the best accuracy to measure radioactivity in brain with PET and the parent 
radioligand in plasma with radioHPLC.  
6.1.2.1 Dose Escalation 
None. 
6.1.2.2 Dose Limiting Toxicity 
Toxicity from this radiolabeled drug comes from radioactive emissions and the mass dose of the 
nonradioactive carrier. Both the injected radioactivity and mass dose are many-fold lower than 
that required to cause toxicity. 
 
 


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6.1.2.3 Dose Modifications 
The dose will not be modified by toxicity. Instead, the dose may be less than that 
prescribed, based on the PI’s judgment of the magnitude of noise that will be acceptable in the 
brain and blood measurements. 
6.1.2.4 Drug Administration 
 
The radioligand will be injected intravenously.  
 
6.2 
Preparation/Handling/Storage/Accountability  
The radioligands are prepared by the NIMH radiochemistry laboratory and handled by 
the PET Department radiopharmacy according to the associated INDs and SOPs. The 
radioligands have minimal storage because they must be injected within one hour of their 
preparation. 
6.2.1 Acquisition and Accountability 
The radioligand will be delivered by the NIMH radiochemistry laboratory to the PET 
Department’s radiopharmacy. Acquisition and accountability are the responsibility of the NIMH 
radiochemistry laboratory. 
6.2.2 Formulation, Appearance, Packaging, and Labeling 
Each product will be formulated in sterile, apyrogenic saline containing 10% dehydrated 
alcohol in a single-use vial and labeled according to requirements for PET drug products 
described in USP Chapter <823>.  The following label will be affixed directly to the vials prior 
to filling: 
 
 
 
Two additional labels are placed on the outer lead shielding used to transport the vial to 
the radiopharmacy: 
 
 


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6.2.3 Product Storage and Stability 
Products are stable at controlled room temperature for the one-hour expiration period and 
have no additional storage requirements. Product vials are expected to be single-use, but if the 
seal is broken and additional product must later be withdrawn, the same storage conditions and 
original expiration time would apply. 
6.2.4 Preparation 
Products are provided as sterile, directly injectable solution in a multi-dose vial. The PET 
radiopharmacist will aseptically remove from the multi-dose vial only the volume required for a 
participant dose. If necessary, this volume will be diluted with 0.9% normal saline, USP to 12 
mL 
6.3 
Measures to Minimize Bias: Randomization and Blinding 
This study is neither randomized nor blinded. 
6.4 
Study Intervention Compliance 
This study is neither randomized nor blinded. 
6.5 
Concomitant Therapy 
Not applicable. 
7 
STUDY INTERVENTION DISCONTINUATION AND PARTICIPANT 
DISCONTINUATION/WITHDRAWAL  
7.1 
Discontinuation of Study Intervention 
Discontinuation instituted by the investigator has been rare in our PET studies, but would 
likely occur during one of the two or three scans (i.e., MRI, one or two PETs). Examples include 
a participant experiencing such anxiety that the investigator recommends study discontinuation, 
even though the participant is willing to proceed. More specifically, the PI may discontinue or 
withdraw a participant from the study for the following reasons: 
• 
Disease progression that requires discontinuation of the study intervention, which is 
unlikely for this relatively short study. 
• 
If any clinically adverse event (AE)or other medical condition or situation occurs 
such that continued participation in the study would not be in the best interest of the 
participant. 
• 
Investigator discretion – e.g., excessive anxiety of the participant 
• 
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Any new clinically relevant finding will be reported as an AE, and the cause of 
discontinuation will be recorded in CRIS. In addition to discontinuation instituted by the PI, the 
participant may discontinue (i.e., withdraw) from the study at any point for any reason. 
7.2 
Participant Discontinuation/Withdrawal from the Study 
Prior to removal from study, effort must be made to have all subjects complete a safety 
visit approximately 2 days following the last dose of study therapy. 
Participants are free to withdraw from participation in the study at any time upon request.  
An investigator may discontinue or withdraw a participant from the study for the following 
reasons: 
• If the participant meets an exclusion criterion (either newly developed or not previously 
recognized) that precludes further study participation 
• Subject has completed the study follow-up period 
• Death 
• Screen Failure 
The reason for participant discontinuation or withdrawal from the study will be recorded on 
the Case Report Form (CRF).  
7.3 
Lost to Follow-up 
A participant will be considered lost to follow-up if s/he fails to return for a scheduled visit 
and is unable to be contacted by the study site staff. The following actions must be taken if a 
participant fails to return to the clinic for a required study visit: 
• The site will attempt to contact the participant and reschedule the missed visit as soon as 
practicable and counsel the participant on the importance of maintaining the assigned visit 
schedule. Concomitantly, we will ascertain whether the participant wishes to and/or should 
continue in the study. 
• Before a participant is deemed lost to follow-up, the PI or their designee will make every 
effort to regain contact with the participant (where possible, three telephone calls and, if 
necessary, a certified letter to the participant’s last known mailing address or local 
equivalent methods). These contact attempts will be documented in the participant’s 
medical record or study file.  
• Should the participant continue to be unreachable, he or she will be considered to have 
withdrawn from the study with a primary reason of lost to follow-up. 
8 
STUDY ASSESSMENTS AND PROCEDURES 
8.1 
Screening Procedures 
Screening activities performed prior to obtaining informed consent: 
Minimal risk activities that may be performed before the subject has signed a consent 
include the following:  
• Email, written, in person or telephone communications with prospective subjects.  
• Review of existing medical records to include H&P, laboratory studies, etc.   


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• Review of existing MRI, x-ray, or CT images. 
• Review of existing photographs or videos. 
• Review of existing pathology specimens/reports from a specimen obtained for diagnostic 
purposes. 
Screening activities performed after a consent has been signed: 
Prior to consenting to this study, participants will have undergone initial screening under 
protocol 01M0254, which allow for the sharing of collected data.  With the first visit under this 
protocol we will require that all participants have an updated physical examination, psychiatric 
evaluation and specific laboratory tests as outlined in the Schedule of Events.  Results of these 
tests will identify participants who should be excluded because of active medical problems or 
make participation in the protocol unsafe.   
The lab tests are described in Section 5.2 (Exclusion Criteria #1). MDD participants will 
be evaluated for their ability and willingness to tolerate study procedures such as arterial line and 
lying still in the PET scanner. 
8.2 
Study Evaluations & Procedures 
In addition to the screening procedures described in Section 8.1, all participants will 
undergo: 
• Brain MRI. A brain MRI will be obtained for anatomic localization and will be 
performed on a 3 Tesla scanner located at the NIH Clinical Center (Bethesda, 
Maryland). The MRI will take about one hour. Participants will undergo safety 
screening prior to the MRI to rule out contraindications such as cardiac pacemaker. If 
the participant has had a recent brain MRI suitable for PET imaging quantification, 
this test need not be repeated. 
• Pregnancy Tests. For women of childbearing potential, urine pregnancy testing will 
be done within the 24 hours prior to any MRI or PET scan. If the pregnancy test is 
positive, PET and MRI will not be done, and the participant will be removed from the 
protocol. 
8.2.1 PET Procedures 
• Radioligand. [11C](R)-rolipram will be prepared according to the IND and 
administered via an indwelling intravenous catheter over approximately one to three 
minutes. 
• Insertion of the intravenous line. An intravenous line will be placed in the arm. The 
venous line will be used to inject the radioligand and will be removed at the end of 
the day. The IV line may be replaced if it fails to remain patent. 
• Arterial line placement. After the presence of adequate ulnar collateral flow has been 
confirmed, a radial artery catheter will be inserted by the Anesthesiology Department 
or the Vascular Access Department. Before catheter insertion, the skin at the puncture 
site will be locally anesthetized.  
• PET scans. Brain PET imaging will be performed using a PET/CT scanner. 
Participants will be placed on the scanner bed. The participant’s head may be secured 
with a head holder or a thermoplastic mask to prevent excessive motion, but the mask 
can be removed if the participant finds it uncomfortable. A CT transmission scan will 


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be performed to measure and correct for attenuation. Tracer infusions will be 
performed when the participant is already on the scanner bed. After an intravenous 
bolus of each radioligand, we will collect about 25 arterial samples. More blood 
samples may be necessary for longer scans. Arterial sampling will initially be 
performed continuously at early time points and discretely at later time points, but 
this plan can be modified if required to improve the quality of the data. The total 
amount of blood withdrawal is described in Section 8.2.3. PET images will be 
acquired for up to four hours. The scans generally will last approximately 90 minutes 
each, with the initial scan prior to ketamine infusion, and the subsequent scan to be 
performed up to 1 week after ketamine infusion. When the scan is completed, the 
arterial and/or venous lines will be removed, and the participant will be instructed to 
void frequently to minimize radiation exposure.  
8.2.2 Clinical Rating Scales 
The following rating scales may be administered to MDD participants at baseline (within six 
weeks of entry into the protocol). Clinical rating scales also will be performed after ketamine 
infusion, and will be performed by MIB clinical staff, unless these scales are to be performed 
post-ketamine by ETPB staff under their protocols, in which case the scales will not be repeated. 
Beck Depression Inventory, Second Edition (BDI-II) 
The BDI-II is a 21-question, multiple-choice, self-report inventory [32]. The BDI-II is used to 
assess the existence and severity of symptoms of depression. In addition, responses indicate 
changes in sleep, appetite, agitation, concentration, and energy. When completing the BDI-II, 
individuals are asked to consider each statement as it relates to the way they have felt for the past 
two weeks. The estimated time to administer this scale is 10-15 minutes. 
Hamilton Psychiatric Rating Scale for Anxiety (HAM-A) 
The HAM-A [33] is a widely used observational rating measure of anxiety severity. The scale 
consists of 14 items. Each item is rated on a scale of 0 to 4. This scale will be administered to 
assess the severity of anxiety and its improvement during the course of therapy. The HAM-A 
total score is the sum of the 14 items and the score ranges from 0 to 56. The estimated time to 
administer this scale is 20 minutes. 
Hamilton Depression Rating Scale (HAM-D) 
The HAM-D [34] is a widely used observational rating measure of depression severity. The 
HAM-D will be administered to assess the severity of depressive symptoms. It assesses both the 
presence and severity of individual signs and symptoms characterizing depression without 
psychotic features. The estimated time to administer this scale is 30 minutes. 
Montgomery-Asberg Depression Rating Scale (MADRS) 
The MADRS [35] is a 10-item instrument used to evaluate depressive symptoms in adults and to 
assess any changes to those symptoms. Inter-rater reliability of the scale is high, and scores 
correlate significantly with those of the HAM-D. Each of the 10 items is rated on a scale of 0 to 
6, with differing descriptors for each item. These individual item scores are added together to 
form a total score, which can range between 0 and 60 points. The estimated time to administer 
this scale is 20 minutes. 


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Massachusetts General Hospital Cognitive and Physical Functioning Questionnaire (MGH-
CPFQ) 
The MGH-CPFQ [36] is a brief (7-item) self-report inventory used to assess rates of significant 
cognitive symptoms, sleepiness, and fatigue. The estimated time to administer this scale is five 
minutes. 
Snaith-Hamilton Pleasure Scale (SHAPS) 
The SHAPS [37] is a 14-item self-report instrument developed to assess hedonic capacity and 
has been validated in participants with MDD. The estimated time to administer this scale is five 
minutes. 
Clinician-Administered Dissociative States Scale (CADSS) 
The CADSS is a clinician-administered measure of perceptual, behavioral and attentional 
changes occurring during dissociative experiences that has been tested in healthy subjects and 
post-traumatic stress disorder (PTSD). This scale involves 19 self-reported questions and eight 
observer ratings scored from 0 (not at all) to 4 (extremely). To characterize dissociative 
responses to ketamine, the CADSS will be sorted into five subscores with apparent face validity 
based on published scales that also assess dissociative states: body perception, environmental 
perception, feelings of unreality, memory impairment and time perception. 
 
These rating scales include questions regarding depression and suicidality. If during the 
course of these evaluations, suicidality is noted, a clinical risk assessment will be performed by a 
licensed clinician, and the NIMH psychiatric consultation team will be consulted as needed for 
acute safety concerns. Otherwise, participants will be referred to their mental health provider as 
appropriate.  
8.2.3 Biospecimen Evaluations 
After injection of the radioligand, arterial sampling will be performed continuously at 
early time points and discretely at later time points, but this plan can be modified if required to 
improve quality of data. Participants may have arterial or venous blood sampling. The total 
amount of blood drawn shall not exceed 10.5 mL/kg or 550 mL, whichever is smaller, over any 
eight-week period. 
8.2.4 Correlative Studies for Research/Pharmacokinetic Studies 
The concentration of parent radioligand in arterial plasma is used in conjunction with 
PET measurements to calculate the density of PDE4 in brain. 
8.2.5 Samples for Genetic/Genomic Analysis 
No samples will be collected for genetic or genomic analyses. 
8.3 
Safety and Other Assessments 
a. Samples for safety bloods will not be collected on the day of the PET scan. . 
b. Pregnancy Tests.  For women of childbearing potential, urine pregnancy testing will 
be done within the 24 hours prior to any MRI or PET scan. If the pregnancy test is 
positive, PET and MRI will not be done, and the participant will be removed from the 
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c. Follow-up Procedures. Participants will be contacted one to three business days after 
each PET scan to determine whether they have had any untoward sequelae. 
d. Participants will continue to see their mental health care providers throughout their 
participation and monitoring for worsening depressive symptoms and suicidality. 
e. Study Team will communicate with the subject’s PCP mental health team to ensure 
that they are aware that the participant is participating in the study. 
 
8.4 
Adverse Events and Serious Adverse Events 
8.4.1 Definition of Adverse Event 
AEs are defined as any untoward medical occurrence associated with the use of an 
intervention in humans, whether or not the AE is considered intervention-related (21 CFR 312.32 
(a)). 
8.4.2 Definition of Serious Adverse Events (SAE) 
An AE or suspected adverse reaction is considered "serious" if, in the view of either the 
investigator or sponsor, it results in any of the following outcomes: death; a life-threatening AE; 
inpatient hospitalization or prolongation of existing hospitalization; a persistent or significant 
incapacity or substantial disruption of the ability to conduct normal life functions; or a congenital 
anomaly/birth defect. Important medical events that do not result in death, are not life-
threatening, or do not require hospitalization may be considered serious when, based upon 
appropriate medical judgment, they may jeopardize the participant and may require medical or 
surgical intervention to prevent one of the outcomes listed in this definition. Examples of such 
medical events include allergic bronchospasm requiring intensive treatment in an emergency 
room or at home, blood dyscrasias or convulsions that do not result in inpatient hospitalization, 
or the development of drug dependency or drug abuse. 
8.4.3 Classification of an Adverse Event 
8.4.3.1 Severity of Event 
The following guidelines will be used to describe severity.  
• Mild – Events require minimal or no treatment and do not interfere with the 
participant’s daily activities.  
• Moderate – Events result in a low level of inconvenience or concern with the 
therapeutic measures. Moderate events may cause some interference with functioning. 
• Severe – Events interrupt a participant’s usual daily activity and may require 
systemic drug therapy or other treatment. Severe events are usually potentially life-
threatening or incapacitating. Notably, the term “severe” does not necessarily equate to 
“serious”. 
8.4.3.2 Relationship to Study Intervention 
All adverse events (AEs) must have their relationship to study intervention assessed by the 
investigator who examines and evaluates the participant based on temporal relationship and 
his/her clinical judgment. The degree of certainty about causality will be graded using the 
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• Definitely Related – There is clear evidence to suggest a causal relationship, and other 
possible contributing factors can be ruled out. The clinical event, including an abnormal 
laboratory test result, occurs in a plausible time relationship to study intervention 
administration and cannot be explained by concurrent disease or other drugs or 
chemicals. The response to withdrawal of the study intervention (dechallenge) should be 
clinically plausible. The event must be pharmacologically or phenomenologically 
definitive, with use of a satisfactory rechallenge procedure if necessary. 
• Probably Related – There is evidence to suggest a causal relationship, and the influence 
of other factors is unlikely. The clinical event, including an abnormal laboratory test 
result, occurs within a reasonable time after administration of the study intervention, is 
unlikely to be attributed to concurrent disease or other drugs or chemicals, and follows a 
clinically reasonable response on withdrawal (dechallenge). Rechallenge information is 
not required to fulfill this definition. 
• Potentially Related – There is some evidence to suggest a causal relationship (e.g., the 
event occurred within a reasonable time after administration of the trial medication). 
However, other factors may have contributed to the event (e.g., the participant’s clinical 
condition, other concomitant events). Although an AE may rate only as “possibly related” 
soon after discovery, it can be flagged as requiring more information and later be 
upgraded to “probably related” or “definitely related”, as appropriate. 
• Unlikely to be related – A clinical event, including an abnormal laboratory test result, 
whose temporal relationship to study intervention administration makes a causal 
relationship improbable (e.g., the event did not occur within a reasonable time after 
administration of the study intervention) and in which other drugs or chemicals or 
underlying disease provides plausible explanations (e.g., the participant’s clinical 
condition, other concomitant treatments). 
• Not Related – The AE is completely independent of study intervention administration, 
and/or evidence exists that the event is definitely related to another etiology. There must 
be an alternative, definitive etiology documented by the clinician.] 
8.4.3.3 Expectedness  
The PI will be responsible for determining whether an AE is expected or unexpected. An 
AE will be considered unexpected if the nature, severity, or frequency of the event is not 
consistent with the risk information previously described for the study intervention. 
8.4.4 Time Period and Frequency for Event Assessment and Follow-Up 
The occurrence of an AE or SAE may come to the attention of study personnel during 
study visits and interviews of a study participant presenting for medical care, or upon review by 
a study monitor. 
All AEs including local and systemic reactions not meeting the criteria for SAEs will be 
captured on the appropriate case report form (CRF). Information to be collected includes event 
description, time of onset, clinician’s assessment of severity, relationship to study product 
(assessed only by those with the training and authority to make a diagnosis), and time of 


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resolution/stabilization of the event. All AEs occurring during the study must be documented 
appropriately regardless of relationship. All AEs will be followed to adequate resolution. 
Any medical condition that is present at the time that the participant is screened will be 
considered as baseline and not reported as an AE. However, if the study participant’s condition 
deteriorates at any time during the study, it will be recorded as an AE.  
Changes in the severity of an AE will be documented to allow an assessment of the 
duration of the event at each level of severity to be performed. AEs characterized as intermittent 
require documentation of onset and duration of each episode. 
Credentialed clinicians will record all reportable events with start dates occurring any time 
after informed consent is obtained until seven (for non-SAEs) or 30 days (for SAEs) after the last 
day of study participation. At each study visit, the investigator will inquire about the occurrence 
of AE/SAEs since the last visit. Events will be followed for outcome information until resolution 
or stabilization. 
8.4.5 Adverse Event Reporting  
Non-SAEs will be reported to the ISM (annually), to the IRB at the time of Continuing 
Review and to the Sponsor at regular intervals per request. 
8.4.6 Serious Adverse Event Reporting  
It is both the Principal Investigator’s (PI) and the Sponsor’s responsibility to ensure the 
safety of those on the clinical trial.  The PI is responsible for tracking adverse events during the 
study and providing adverse events lists to the Sponsor at regular intervals per request. These 
may be requested quarterly and will be requested no less than once a year at the time of IND 
annual report to the FDA. ALL AEs that are collected, as determined by the written protocol, 
should be tracked in the ORSC RSS’ template AE Tracker or similar document. If the sponsor 
determines that adverse events are occurring more frequently or more severely than the written 
protocol had expected and/or anticipated, this should be submitted in an IND Safety Report, as 
described below.  In addition, the PI is responsible for updating the Sponsor about known risks 
from the drug, as discovered from literature searches or other means. 
In accordance with the requirements of 21 CFR 312.32, the PI or designee will report all 
SAEs, whether or not these are considered related to the investigational drug or study 
intervention, that occur throughout the study to the Sponsor, including those events listed in the 
protocol or Investigator’s Brochure as anticipated to occur, as follows:  
Deaths:  within 24 hours of the investigator’s awareness 
All other SAEs:  within 48 hours of the investigator’s awareness 
All AEs will be sent to the Sponsor quarterly, unless requested more or less 
frequently, for submission to the FDA in the IND Annual Report. 
*“Investigator’s awareness” includes awareness by anyone on the study team. 
The PI will immediately report all deaths and SAEs to the Sponsor by disclosing all event-
related information in a completed MedWatch Form 3500A. This form should include the IND 
number, protocol number, PI name, and an assessment on the reasonable possibility of a 
relationship between the event and the study drug or intervention. MRNs should NOT be 


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included on this form. The completed MedWatch Form 3500A will be sent ENCRYPTED to 
the Clinical Director/CEO and/or designated medical monitor with a copy to the NIH Office of 
Research Support & Compliance (ORSC) Regulatory Support Section. 
The Clinical Director/CEO and/or designated medical monitor will be responsible for 
determining whether the event is reportable to the FDA as an IND Safety Report if it is a serious, 
unexpected, and suspected adverse reaction (SUSAR). If the sponsor determines the SAE meets 
the criteria of a SUSAR, the ORSC will submit an Initial IND Safety Report to the FDA no later 
than 15 calendar days after the PI’s notification of the event to the Sponsor. Deaths or life-
threatening events will be reported to the FDA no later than 7 calendar days after the PI’s 
notification of the event to the Sponsor. The Sponsor will submit any relevant additional 
information in a Follow-up IND Safety Report no later than 15 calendar days after receiving the 
information. All SAEs will be monitored until satisfactory resolution. All AEs and SAEs will be 
documented on appropriate study records. 
8.4.7 NIH Intramural IRB Reporting of IND Safety Reports 
Only IND Safety Reports that meet the definition of an unanticipated problem or is new 
information that might affect the willingness of subjects on the NIH study to enroll or remain in 
the study will need to be reported to the NIH Intramural IRB. 
8.4.8 Events of Special Interest  
None 
8.4.9 Reporting of Pregnancy  
Participants will be excluded if they are or may become pregnant. 
8.5 
Unanticipated Problems 
8.5.1 Definition of Unanticipated Problems (UP) 
Any incident, experience, or outcome that meets all of the following criteria: 
• Unexpected in terms of nature, severity, or frequency given (a) the research procedures 
that are described in the protocol-related documents, such as the Institutional Review 
Board (IRB)-approved research protocol and informed consent document; and (b) the 
characteristics of the participant population being studied; and 
• Related or possibly related to participation in the research (“possibly related” means there 
is a reasonable possibility that the incident, experience, or outcome may have been 
caused by the procedures involved in the research); and 
• Suggests that the research places participants or others (which many include research 
staff, family members or other individuals not directly participating in the research) at a 
greater risk of harm (including physical, psychological, economic, or social harm) than 
was previously known or expected. 
8.5.2  Unanticipated Problem Reporting  
The investigator will report unanticipated problems (UPs) to the NIH Institutional Review Board 
(IRB) as per Policy 801. 


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9 
STATISTICAL CONSIDERATIONS 
9.1 
Statistical Hypothesis 
• Primary Endpoint(s): VT of [11C](R)-rolipram prior to ketamine infusion compared to 
VT of [11C](R)-rolipram after ketamine infusion, within one week. We hypothesize 
that ketamine infusion will increase rolipram binding similar to that previously 
described for SSRI treatment. 
• Secondary Endpoint(s): We will explore correlations between changes in [11C](R)-
rolipram binding and clinical rating scales.  
9.2 
Sample Size Determination 
The only existing database of patients scanned for PDE4 at baseline and after treatment is 
the one described by Fujita et al. This work, whose patients were very similar to the ones 
targeted in this study, analyzed 23 MDD subjects with 11C-rolipram at baseline and after 8 weeks 
of antidepressant SSRI treatment. MDD subjects had a ~20% reduction in rolipram binding 
compared to controls, and the SSRI treatment significantly increased 11C-rolipram binding by 
12% (P<0.001). Consequently, we aim at studying a population of the same size as the one that 
revealed a significant change with pharmacological treatment. Considering dropouts, we wish to 
recruit up to 35 subjects, with the goal of scanning 23. Correlation/regression analyses will be 
performed by controlling for possible confounding factors such as age and sex. 
9.3 
Populations for Analyses 
Patients with major depressive disorder that qualify for ketamine treatment. 
9.3.1 Evaluable for toxicity  
No toxicity is expected from the radioligand. 
9.3.2 Evaluable for objective response  
Participants will be evaluated on the basis of completion of two PET scans as the primary 
endpoint. Ketamine infusion has been shown to exert an antidepressant effect, which will be 
evaluated based on changes in clinical rating scales from pre-ketamine baseline, which will then 
be correlated to change in PET scans.  
9.3.3 Evaluable Non-Target Disease Response 
Participants may exhibit changes in clinical rating scales, in [11C](R)-rolipram binding, 
neither, or both. Correlations will be made to determine if clinical improvement based on 
ketamine infusion is associated with [11C](R)-rolipram binding. 
9.4 
Statistical Analyses 
9.4.1 General Approach 
For the primary endpoint of change in [11C](R)-rolipram binding, we will compare the 
pre-ketamine scans within each subject with their post-ketamine scans using paired sample t-test. 
For the secondary endpoint “Is there a correlation between VT and clinical rating 
scales?”, we will use correlation analyses between the modeling results and the results of the 
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9.4.2 Analysis of the Primary Endpoints 
[11C](R)-rolipram binding assessed as VT will be compared within subjects with a paired 
sample t-test. VT will be calculated using pharmacokinetic modeling. 
 
 
9.4.3 Analysis of the Secondary Endpoint(s) 
The outcome measures for the correlative studies will be the VT and the results of the 
clinical rating scales.  
9.4.4 Safety Analyses 
None. 
9.4.5 Baseline Descriptive Statistics 
Demographic variables, such as age and weight, will be summarized as mean +/- SD. 
9.4.6 Sub-Group Analyses 
The sample will be analyzed by sex and age, but is too small to be analyzed by other 
demographic characteristics. 
9.4.7 Tabulation of individual Participant Data 
Individual participant data will be listed by measure and timepoint. 
9.4.8 Exploratory Analyses 
None. 
10 
REGULATORY AND OPERATIONAL CONSIDERATIONS 
10.1 
Informed Consent Process 
10.1.1 Consent/Assent Procedures and Documentation 
Only the study investigators designated to obtain consent will be allowed to do so. All 
study investigators obtaining informed consent must have completed the NIMH HSPU training 
“Elements of Successful Informed Consent”. When consent is conducted for subjects with MDD, 
HSPU must be present. 
The informed consent document will be provided as a physical or electronic document to 
the participant or consent designee as applicable for review prior to consenting. A designated 
study investigator will carefully explain the procedures and tests involved in this study, and the 
associated risks, discomfort and benefits. In order to minimize potential coercion, as much time 
as is needed to review the document will be given, including an opportunity to discuss it with 
friends, family members and/or other advisors, and to ask questions of any designated study 
investigator. A signed informed consent document will be obtained prior to any research 
activities taking place. 
The initial consent process as well as re-consent, when required, may take place in person 
or remotely (e.g., via telephone or other NIH approved remote platforms used in compliance 


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with policy, including HRPP Policy 303) per discretion of the designated study investigator and 
with the agreement of the participant/consent designee(s). Whether in person or remote, the 
privacy of the subject will be maintained. Consenting investigators (and participant when in 
person) will be located in a private area (e.g., clinic consult room). When consent is conducted 
remotely, the participant will be informed of the private nature of the discussion and will be 
encouraged to relocate to a more private setting if needed. If the consent process is occurring 
remotely, participants and investigators will view individual copies of the approved consent 
document on screens at their respective locations; the same screen may be used when both the 
investigator and the participant are co-located but this is not required. 
Note: When required, the witness signature will be obtained similarly as described for the 
investigator and participant below. 
When a hand signature on an electronic document is used for the documentation of 
consent, this study will use the following electronic platform to obtain the required signatures: 
• 
iMedConsent platform (which is 21 CFR Part 11 compliant) 
Both the investigator and the participant will sign the electronic document using a finger, 
stylus or mouse. Electronic signatures (i.e., the “signature” and a timestamp are digitally 
generated) will not be used. 
The consent process will be documented in CRIS. A copy of the consent form will be 
given to the participant and also uploaded in CRIS. 
10.1.2 Consent for minors when they reach the age of majority  
Minors will not be enrolled in the study. 
10.1.3 Considerations for Consent of NIH staff, or family members of study team members 
 
Consent for NIH employees will be obtained as described in Section 5.3. 2 
10.1.4 Consent of Subjects who are, or become, decisionally impaired 
Adults unable to give consent are excluded from enrolling in the protocol.  For those 
subjects that become incapacitated, they will be removed from the study.  
10.2 
Study Discontinuation and Closure 
This study may be temporarily suspended or prematurely terminated if there is sufficient 
reasonable cause. If the study is prematurely terminated or suspended, the PI will promptly 
inform study participants, the IRB, and the sponsor. Study participants will be contacted, as 
applicable, and be informed of changes to the study visit schedule. 
Circumstances that may warrant termination or suspension include, but are not limited to: 
• Determination of unexpected, significant, or unacceptable risk to participants. 
• Demonstration of efficacy that would warrant stopping. 
• Insufficient compliance with protocol requirements. 
• Data that are not sufficiently complete and/or evaluable. 
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The study may resume once concerns about safety, protocol compliance, and data quality are 
addressed, and satisfy the sponsor, the IRB, and/or the Food and Drug Administration (FDA). 
10.3 
Confidentiality and Privacy 
Participant confidentiality and privacy are strictly held in trust by the participating 
investigators, their staff, and the sponsor(s). This confidentiality is extended to cover testing of 
biological samples in addition to the clinical information relating to participants. Therefore, the 
study protocol, documentation, data, and all other information generated will be held in strict 
confidence. 
All research activities will be conducted in as private a setting as possible. 
The study monitor, other authorized representatives of the sponsor, representatives of the 
IRB, and/or regulatory agencies may inspect all documents and records required to be 
maintained by the investigator, including but not limited to medical records (office, clinic, or 
hospital) and pharmacy records for the participants in this study. The clinical study site will 
permit access to such records. 
The study participant’s contact information will be securely stored at the NIH for internal 
use during the study. At the end of the study, all records will continue to be kept in a secure 
location for as long a period as dictated by the reviewing IRB, institutional policies, or sponsor 
requirements. 
To further protect the privacy of study participants, a Certificate of Confidentiality 
(COC) has been issued by the NIH. This certificate protects identifiable research information 
from forced disclosure. It allows the investigator and others who have access to research records 
to refuse to disclose identifying information on research participation in any civil, criminal, 
administrative, legislative, or other proceeding, whether at the federal, state, or local level. By 
protecting researchers and institutions from being compelled to disclose information that would 
identify research participants, COCs help achieve the research objectives and promote 
participation in studies by helping ensure confidentiality and privacy to participants. 
See Section 10.4 for information regarding sharing of research data during or after 
completion of the study. 
10.4 
Future use of Stored Specimens and Data 
Genetic testing will not be performed in this protocol. No samples will be stored or 
shared.  
In the consent form, we ask permission of the participant (yes/no response) to share 
imaging and other research data during or after completion of the study with collaborating 
laboratories at the NIH or outside of the NIH and/or submitted to open-access repositories for 
secondary research that may or may not involve a collaboration with the NIMH. Such open 
access repositories (e.g., OpenNeuro, sponsored by the NIMH) allows anyone to access the data 
for any purpose. Data will be stripped of all identifiers, including name, address, contact 
information, and medical record number prior to sharing. In addition, the face will be removed 
from MRI images. The data may be coded, but the key to the code will not be provided to any 
collaborator or party external to the NIH. After the study is completed, the de-identified data and 


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the code may be indefinitely maintained at the NIH and used for secondary analyses. In contrast 
to data, no biological samples will be shared. 
10.5 
Safety Oversight 
Monitoring for this study will be performed by the independent safety monitor (ISM), 
Kenneth Towbin, MD, who is a board-certified psychiatrist with full clinical privileges at the 
NIH Clinical Center.   
The PI will prepare a report on data and safety parameters for the ISM approximately 
every 12 months. The ISM will provide a written monitoring report to be submitted to the IRB at 
the time of continuing review. 
10.6 
Clinical Monitoring 
Clinical site monitoring is conducted to ensure that the rights and well-being of trial 
participants are protected, that the reported trial data are accurate, complete, and verifiable, and 
that the conduct of the trial complies with the currently approved protocol/amendment(s), with 
International Conference on Harmonization Good Clinical Practice (ICH GCP), and with 
applicable regulatory requirement(s). 
As per ICH-GCP 5.18 and FDA 21 CFR 312.50 clinical protocols are required to be 
adequately monitored. Monitoring for the NIH site will be conducted according to the "NIMH 
Intramural Program Guidelines for Monitoring of Clinical Trials". Monitors under contract to the 
NIMH OCD ORO will visit the NIH site to monitor aspects of the study in accordance with the 
appropriate regulations and the approved protocol. The objectives of a monitoring visit will be: 
1) to verify the existence of signed informed consent documents and documentation of the ICF 
process for each monitored subject; 2) to verify the prompt and accurate recording of all 
monitored data points, and prompt reporting of all SAEs; 3) to compare abstracted information 
from clinical databases (e.g. CTDB) with individual subjects' records and source documents 
(subjects' charts, laboratory analyses and test results, physicians' progress notes, nurses' notes, 
and any other relevant original subject information); and 4) to help ensure investigators are in 
compliance with the protocol. The monitors also will inspect the clinical site regulatory files to 
ensure that regulatory requirements (Office for Human Research Protections-OHRP), FDA, and 
applicable guidelines (ICH-GCP) are being followed. During the monitoring visits, the 
investigator (and/or designee) and other study personnel will be available to discuss the study 
progress and monitoring visit. 
The investigator (and/or designee) will make study documents (e.g., consent forms, clinical 
database records and pertinent hospital/sources or clinical records readily available for inspection 
by the local IRB, FDA, the site monitors, and the NIMH staff for confirmation of the study data. 
A specific protocol monitoring plan will be discussed with the Principal Investigator and 
study staff. The plan will outline the frequency of monitoring visits based on such factors as 
study enrollment, data collection status and regulatory obligations.   
10.7 
Quality Assurance and Quality Control 
Each clinical site will perform internal quality management of study conduct, data and 
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Following written Standard Operating Procedures (SOPs), the monitors will verify that the 
clinical trial is conducted, and data are generated and biological specimens are collected, 
documented (recorded), and reported in compliance with the protocol, International Conference 
on Harmonization Good Clinical Practice (ICH GCP), and applicable regulatory requirements 
(e.g., Good Laboratory Practices (GLP), Good Manufacturing Practices (GMP)).  
The investigational site will provide direct access to all trial related sites, source 
data/documents, and reports for the purpose of monitoring and auditing by the sponsor, and 
inspection by local and regulatory authorities. 
10.8 
Data Handling and Record Keeping 
10.8.1 Data Collection and Management Responsibilities 
Data collection is the responsibility of the clinical trial staff at the site under the 
supervision of the PI. The PI is responsible for ensuring the accuracy, completeness, legibility, 
and timeliness of the data reported. 
All source documents will be completed in a neat, legible manner to ensure accurate 
interpretation of data. Hardcopies of the study visit worksheets will be provided for use as source 
document worksheets for recording data for each participant enrolled in the study. Data recorded 
in the electronic case report form (eCRF) derived from source documents will be consistent with 
the data recorded on the source documents.  
Clinical data (including AEs, eligibility, and primary outcome data) will be entered into 
the Clinical Trials Database (CTDB) at NIH. CTDB complies with the Federal Information 
Security Management Act of 2002 and 21 CFR Part 11. The data system includes audit trail, 
password protection, and control staff access level to the application and data. Edit checks 
implemented at the eCRF include: data type validation and numeric range checks. Clinical data 
will be entered directly from the source documents. 
10.8.2 Study Records Retention 
Study documents should be retained for a minimum of 2 years after the last approval of a 
marketing application in an International Conference on Harmonisation (ICH) region and until 
there are no pending or contemplated marketing applications in an ICH region or until at least 2 
years have elapsed since the formal discontinuation of clinical development of the study 
intervention, and as per the NIH Intramural Records Retention Schedule. No records will be 
destroyed without the written consent of the sponsor, if applicable. It is the responsibility of the 
sponsor to inform the investigator when these documents no longer need to be retained. 
10.9 
Protocol Deviations and Non-Compliance 
The PI will use continuous vigilance to identify and report deviations and/or non-
compliance to the NIH Institutional Review Board as per Policy 801. All deviations will be 
addressed in study source documents, reported to the NIMH Program Official and the IND 
sponsor; Dr. Maryland Pao, Clinical Director, holds both of these positions. The investigator will 
be responsible for knowing and adhering to the reviewing IRB requirements. 
 
 


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10.9.1 NIH Definition of Protocol Deviation 
A protocol deviation is any changed, divergence, or departure from the IRB-approved 
research protocol.  
• Major deviations: Deviations from the IRB approved protocol that have, or may have the 
potential to, negatively impact the rights, welfare or safety of the subject, or to 
substantially negatively impact the scientific integrity or validity of the study. 
• Minor deviations: Deviations that do not have the potential to negatively impact the 
rights, safety or welfare of subjects or others, or the scientific integrity or validity of the 
study. 
10.10   Publication and Data Sharing Policy 
10.10.1   Human Data Sharing Plan 
This study will be conducted in accordance with the following publication and data 
sharing policies and regulations: 
National Institutes of Health (NIH) Public Access Policy, which ensures that the public 
has access to the published results of NIH funded research. It requires scientists to submit final 
peer-reviewed journal manuscripts that arise from NIH funds to the digital archive PubMed 
Central upon acceptance for publication. 
This study will comply with the NIH Data Sharing Policy and Policy on the 
Dissemination of NIH-Funded Clinical Trial Information and the Clinical Trials Registration and 
Results Information Submission rule. As such, this trial will be registered at ClinicalTrials.gov, 
and results information from this trial will be submitted to ClinicalTrials.gov. In addition, every 
attempt will be made to publish results in peer-reviewed journals.   
10.10.2  Genomic Data Sharing Compliance 
No genomic data will be acquired during this study. 
10.11 Conflict of Interest Policy 
The independence of this study from any actual or perceived influence, such as by the 
pharmaceutical industry, is critical.  Therefore, any actual conflict of interest of persons who 
have a role in the design, conduct, analysis, publication, or any aspect of this trial will be 
disclosed and managed. Furthermore, persons who have a perceived conflict of interest will be 
required to have such conflicts managed in a way that is appropriate to their participation in the 
design and conduct of this trial.  The study leadership in conjunction with the NIMH has 
established policies and procedures for all study group members to disclose all conflicts of 
interest and will establish a mechanism for the management of all reported dualities of interest. 


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11 ABBREVIATIONS 
AE 
Adverse Event 
ANCOVA 
Analysis of Covariance 
CFR 
Code of Federal Regulations 
CLIA 
Clinical Laboratory Improvement Amendments 
CMP 
Clinical Monitoring Plan 
COC 
Certificate of Confidentiality 
CONSORT Consolidated Standards of Reporting Trials 
CRF 
Case Report Form 
DCC 
Data Coordinating Center 
DHHS 
Department of Health and Human Services 
DSMB 
Data Safety Monitoring Board 
DRE 
Disease-Related Event 
EC 
Ethics Committee 
eCRF 
Electronic Case Report Forms 
FDA 
Food and Drug Administration 
FDAAA 
Food and Drug Administration Amendments Act of 2007 
FFR 
Federal Financial Report 
GCP 
Good Clinical Practice 
GLP 
Good Laboratory Practices 
GMP 
Good Manufacturing Practices 
GWAS 
Genome-Wide Association Studies 
HIPAA 
Health Insurance Portability and Accountability Act  
HSPU 
Human Subjects Protection Unit 
IB 
Investigator’s Brochure 
ICH 
International Conference on Harmonisation  
ICMJE 
International Committee of Medical Journal Editors 
IDE 
Investigational Device Exemption 
IND 
Investigational New Drug Application 
IRB 
Institutional Review Board 
ISM 
Independent Safety Monitor 
ISO 
International Organization for Standardization 
ITT 
Intention-To-Treat 
LSMEANS Least-squares Means 
MedDRA 
Medical Dictionary for Regulatory Activities 
MOP 
Manual of Procedures 
MSDS 
Material Safety Data Sheet 
NCT 
National Clinical Trial 
NIH  
National Institutes of Health 
NIH IC 
NIH Institute or Center 
OHRP 
Office for Human Research Protections 
PI 
Principal Investigator 
QA 
Quality Assurance 


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QC 
Quality Control 
SAE 
Serious Adverse Event 
SAP 
Statistical Analysis Plan 
SMC 
Safety Monitoring Committee 
SOA 
Schedule of Activities 
SOC 
System Organ Class 
SOP 
Standard Operating Procedure 
UP 
Unanticipated Problem 
US 
United States 
 
 


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