Conditions: Urea Cycle Disorder
Keywords: CPSI deficiency OTC Deficiency AS Deficiency AL Deficiency
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 4
Healthy volunteers: yes

Brief summary:
The objective is to determine if acetohydroxamic acid (AHA) can prevent hydrolysis of urea by inhibiting the bacterial urease of gut flora of both healthy control adults as well as adults with urea cycle disorders

Detailed description:
This project will study the efficacy and safety of the pharmacologic blockade of urease in the nitrogen salvage pathway of intestinal microbes in subjects with partial urea cycle disorders. Additional trapping of ammonia as excretable urea may result in improved nitrogen excretion and reduced ammonia levels.

Urea cycle disorders (UCDs) are a group of disorders resulting from a complete or partial deficiency of one of the 6 enzymes or 2 transporters that comprise the urea cycle, the essential biochemical pathway which converts toxic ammonia into urea. These disorders have as a common feature, a reduced or complete inability to convert ammonia into urea, thereby resulting in high ammonia levels, or hyperammonemia. If untreated, hyperammonemia may result acutely in lethargy and coma, and chronically in intellectual disability. Current treatment for hyperammonemia is suboptimal, thus the search for new treatments is critical.

The urease inhibitor, acetohydroxamic acid (AHA, Lithostat®, Mission Pharmacal), is an FDA-approved product for another indication- the treatment of struvite nephrolithiasis in chronic urinary tract infections in both adults and children.

It is known that many urea-splitting bacteria also exist in the gut, and that in healthy individuals, approximately 15-30% of blood urea is degraded via gut bacteria into ammonia3, which returns to the liver via the portal vein, only to be recycled into urea. This percentage of degraded urea may even be greater in patients with urea cycle disorders, who are on a low protein-diet4 and whose gastrointestinal contents thus likely have lower nitrogen content, promoting bacterial recycling of nitrogen from available urea. Additionally, urea hydrolysis has been shown to be greatest in infants5, precisely the age at which hyperammonemic episodes are the most frequent in UCD patients.

We intend to study if AHA can inhibit gut bacteria degradation of urea, thereby reducing the quantity of ammonia returning to the liver. We intend to investigate this by studying subjects on two occasions at least 3 days apart:

On the first occasion, subjects will receive an intravenous dose of 13C-urea. Following the intravenous bolus of 13C-urea, over the subsequent 4 hours, we will collect several sequential measurements of blood and urine biomarkers from an IV catheter placed in the other arm. The intent is to obtain baseline 13CO2 kinetics in the subject.

On the second occasion, subjects will first receive an oral dose of AHA approximately 1 hour prior to the intravenous 13C-urea dose. Similar sequential measurements of blood and urine biomarkers will be performed. The intent is to observe a reduction in 13CO2 when AHA is administered.

We intend to initially study a cohort of unaffected adult subjects. If successful, we will study adults with partial urea cycle disorders.

This study will be conducted in the Clinical Research Center (CRC) of the Clinical and Translational Research Institute (CTSI) of Children's National Medical Center (CNMC).

Arms:
arm 1: Participants receive a single oral dose of 60 mg/kg acetohydroxamic acid (rounded to the nearest 250 mg) in the fasted state on the morning of the study. After completion of the 4-h study, participants then enter a wash-out period of 3 days. Participants then completed an identical 4-h study in the fasted state without acetohydroxamic acid. arm 2: Participants completed a 4-h study in the fasted state without acetohydroxamic acid. 3 days later, participants then completed an identical 4-h study in the fasted state, after having received a single oral dose of 60 mg/kg acetohydroxamic acid (rounded to the nearest 250 mg).

Interventions: intervention 1: Acetohydroxamic Acid Oral Tablet intervention 2: No treatment
Intervention descriptions: intervention 1: A single oral dose of 60 mg/kg acetohydroxamic acid rounded to the nearest 250 mg tablet. intervention 2: No treatment

Protocol document:
Prot_SAP_ICF_001.pdf: 
 
 
 
 
 
Rare Diseases Clinical Research Network 
Urea Cycle Disorders Consortium 
 
Manipulating the Gut Microbiome in Urea Cycle 
Disorders 
 
 
 
Nicholas Ah Mew 
Children’s National Medical Center 
202-476-5863 
nahmew@childrensnational.org 
 
 
 
 
 
 
 
This protocol is for research purposes only, and should not be 
copied, redistributed or used for any other purpose.  The 
procedures in this protocol are intended only for use by 
Consortium investigators in carefully controlled settings.  The Chair 
of this study should be consulted before using or attempting any 
procedure in this protocol.


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Participating Institutions/Investigators Table  
Principal Investigator: Nicholas Ah Mew, MD
Contact: 
Lillian Assatourian 
Institution:
Children’s National Medical Center 
Address:
111 Michigan Avenue, NW 
Washington, DC 
20010 
Phone:
202-476-6137 (Lillian) 
202-476-5863 (Dr. Ah Mew) 
Fax:
202-476-2390 
Email:
lassatouri@childrensnational.org (Lillian) 
nahmew@childrensnational.org (Dr. Ah Mew) 
 
 
 
Co-Principal Investigator: Marshall Summar, MD
 
Institution:
Children’s National Medical Center 
Address:
111 Michigan Avenue, NW 
Washington, DC 
20010 
Phone:
202-476-5291 
Fax:
202-476-5566 
Email:
msummar@childrensnational.org 
 
 
 
Data Management and Coordinating Center Principal Investigator: Jeffery Krischer, Ph.D.
Contact: 
Amy Holbert 
Institution/ 
Department:
Data Management and Coordinating Center (DMCC); Pediatrics Epidemiology 
Center; University of South Florida 
Address:
3650 Spectrum Blvd; Suite 100; Tampa, FL 33612 
Phone:
(813) 396-9567 
Fax:
(813) 910-5967 
Email:
amy.holbert@epi.usf.edu 
 
 
 
 
 
 
 
 
 
 
 
 
 


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Table of Contents 
1. PROTOCOL SYNOPSIS................................................................................................................. 5 
1.1 Overview ................................................................................................................... 7 
2. SPECIFIC AIMS (HYPOTHESIS AND OBJECTIVES) ......................................................... 8 
3. BACKGROUND ................................................................................................................................. 8 
4. STUDY DESIGN AND METHODS .............................................................................................. 9 
4.1 Inclusion Criteria...................................................................................................... 10 
4.2 Exclusion Criteria .................................................................................................... 10 
4.3 Recruitment of Participants ..................................................................................... 11 
4.4 Retention strategies ................................................................................................ 11 
4.5 Data Elements ......................................................................................................... 11 
4.6 Schedule of Events ................................................................................................. 11 
5. SAFETY MONITORING ................................................................................................................ 12 
5.0 Data and Safety Monitoring Plan ............................................................................. 12 
5.1 Study Oversight ....................................................................................................... 13 
5.2 Definitions and Standards ....................................................................................... 13 
5.3 Expected/Known Risks/Discomforts/Adverse Events .............................................. 14 
5.4 Reporting Timeline .................................................................................................. 15 
5.5 RDCRN Adverse Event Data Management System (AEDAMS) ............................. 16 
5.6 Study Discontinuation .............................................................................................. 16 
5.7 Subject Discontinuation ........................................................................................... 16 
5.8 Data Quality and Monitoring Measures ................................................................... 17 
6. STATISTICAL CONSIDERATIONS .......................................................................................... 17 
7. DATA MANAGEMENT .................................................................................................................. 18 
7.1 Registration ............................................................................................................. 18 
7.2 Data Entry ............................................................................................................... 18 
7.3 Data Quality Control ................................................................................................ 19 
7.4 Laboratory data flow ................................................................................................ 19 
7.5 Study Records Retention ........................................................................................ 19 
7.6 Protocol Deviations ................................................................................................. 19 
8. HUMAN SUBJECTS ...................................................................................................................... 20 
8.1 GCP Statement ....................................................................................................... 20 
8.2 Benefits ................................................................................................................... 20 
8.2.1 Potential Benefits of the Proposed Research to Subjects and Others .............. 20 
8.2.2 Importance of the Knowledge to Be Gained ..................................................... 20 


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8.3 Recruitment ............................................................................................................. 20 
8.4 Written Informed Consent ....................................................................................... 21 
8.5 Process of Consent ................................................................................................. 21 
8.6 Certificate of Confidentiality ..................................................................................... 22 
9. REFERENCES ................................................................................................................................. 22 
10. APPENDICES AND RDCRN INFORMED CONSENT TEMPLATES .......................... 23 
10.1 Appendix ............................................................................................................... 23 
10.2 Informed Consent for Healthy Volunteers ............................................................. 25 
10.3 Informed Consent for Urea Cycle Disorder Participants .......................................... 40 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 


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1. Protocol Synopsis 
Interventional Synopsis 
Protocol Number:
5115 
Protocol Title:
Manipulating the Gut Microbiome in Urea Cycle Disorders 
Study Chair:
Nicholas Ah Mew, MD 
Study Co-Chair:
Marshall Summar, MD 
Statistician:
Robert McCarter, ScD 
Consortium:
Urea Cycle Disorders Consortium 
Participating Sites:
Children’s National Medical Center 
Activation Date:
Pending 
Current Status:
Pre-enrollment 
Sample Size:
Group 1: 8 healthy adult subjects 
Group 2: 8 adult subjects with urea cycle disorders 
Target Enrollment Period:
Group 1: 1 year 
Group 2: 2 years 
Study Phase
I/II 
Study Design:
Open-label, cross-over 
Primary Study Objective:
The objective is to determine if acetohydroxamic acid (AHA) can 
prevent hydrolysis of urea by inhibiting the bacterial urease of gut flora 
of both healthy control adults as well as adults with urea cycle 
disorders 
Secondary Study 
Objective(s):
Determine if the proposed dose of acetohydroxamic acid is safe 
Study Population and Main 
Eligibility/ Exclusion 
Criteria:
A subject may be included in the study if all of the following criteria are 
met: 
 
For Group 1 (healthy adults): 
- 
Ages 18-60 years 
- 
Compliant with receiving medications orally and intravenously 
- 
Compliant with providing blood and urine samples 
 
For Group 2 (adult UCD patients): 
- 
Ages 18-60 years 
- 
Compliant with receiving medications orally and intravenously 
- 
Compliant with providing blood and urine samples 
- 
Established diagnosis of CPSD, OTCD, ASSD or ASLD as 
follows: 
o 
Diagnosis of CPS I deficiency, defined as decreased 
(less than 20 % of control) CPS I enzyme activity in 
liver or an identified pathogenic mutation  
o 
Diagnosis of OTC deficiency, defined as the 
identification of a pathogenic mutation, linkage 
analysis in an affected family, less than 20% of control 
of OTC activity in the liver, or elevated urinary orotate 
(greater than 20 uM/mM) in a random sample or 
following allopurinol loading with absence of 
argininosuccinic acid  
o 
Diagnosis of AS deficiency (Citrullinemia), defined as 
a greater than or equal to 10-fold elevation of citrulline 
in plasma, decreased AS enzyme activity in cultured 
skin fibroblasts or other appropriate tissue, or 
identification of a pathogenic mutation in the AS gene  
o 
Diagnosis of AL deficiency (Argininosuccinic Aciduria, 


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ASA), defined as the presence of argininosuccinic 
acid in the blood or urine, decreased AL enzyme 
activity in cultured skin fibroblasts or other appropriate 
tissue, or identification of a pathogenic mutation in the 
AL gene 
 
A subject may not be included in the study if any one of the following 
criteria is met: 
 
For both Group 1 and Group 2: 
- 
Current or prior Helicobacter pylori infection  
- 
Chronic gastrointestinal illness (e.g., inflammatory bowel 
disease) 
- 
Chronic renal failure 
- 
Taking probiotic medications within a week of study start date 
- 
Currently pregnant or lactating. Documentation of a negative 
pregnancy test within a week prior to testing is required, 
unless pre-menarchal or menopausal, experiencing menses 
that week, or other circumstances which preclude pregnancy 
(e.g. hysterectomy).  
- 
Presence of acute infection at the time of inclusion 
- 
Participation in any other clinical interventional trial or received 
experimental medication within the last 30 days 
- 
Any clinical or laboratory abnormality or medical condition 
that, at the discretion of the investigator, may put the subject 
at an additional risk by participating in this study 
Treatment  
Agent-
Acetohydroxamic Acid (AHA, Lithostat) 
Dosage, schedule, route of 
administration-
Single dose, 60 mg/kg PO 
Safety Issues-
Bone marrow depression (leukopenia, anemia, and thrombocytopenia) 
has occurred in experimental animals receiving large doses of AHA. 
However, only a single dose will be administered in this study, and is 
not likely to result in this adverse effect. 
 
Primary Outcome 
Measures:
Difference in the  time-averaged level of blood 13CO2 after a single 
bolus of intravenous [13C]-Urea, measured on two occasions: once at 
baseline, and once 2-hr after an oral bolus of AHA 
Secondary Outcome 
Measures:
Differences in blood [13C]-Urea, Urea, Ammonia, Glutamine 
Safety Variables
Hemoglobin, White blood count, platelets, AST, ALT, Bilirubin, 
Creatinine 
Statistical Considerations 
(sample size and analysis 
plan):
Longitudinal linear regression models will assess and compare time 
averaged mean changes in blood 13CO2, and blood levels of  [13C]-
urea, ammonia and glutamine. 
A sample size of 8 crossover participants provides 90% power to 
detect a 20% relative difference in the time-averaged level of 13CO2 in 
treatment with AHA versus non-AHA under a 2-tailed type I error of 
0.05. 
Sponsors (federal, state, 
foundation and industry 
support):
Rare Disorders Clinical Research Network, National Institutes of 
Health, National Institute of Child and Human Development  
Mission Pharmacal 


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1.1 Overview 
 
This project will study the efficacy and safety of the pharmacologic blockade of urease 
in the nitrogen salvage pathway of intestinal microbes in subjects with partial urea cycle 
disorders. Additional trapping of ammonia as excretable urea may result in improved 
nitrogen excretion and reduced ammonia levels.  
 
Urea cycle disorders (UCDs) are a group of disorders resulting from a complete or 
partial deficiency of one of the 6 enzymes or 2 transporters that comprise the urea 
cycle, the essential biochemical pathway which converts toxic ammonia into urea. 
These disorders have as a common feature, a reduced or complete inability to convert 
ammonia into urea, thereby resulting in high ammonia levels, or hyperammonemia. If 
untreated, hyperammonemia may result acutely in lethargy and coma, and chronically in 
intellectual disability. Current treatment for hyperammonemia is suboptimal, thus the 
search for new treatments is critical. 
 
The urease inhibitor, acetohydroxamic acid (AHA, Lithostat®, Mission Pharmacal), is an 
FDA-approved product for another indication- the treatment of struvite nephrolithiasis in 
chronic urinary tract infections in both adults and children1,2. 
 
It is known that many urea-splitting bacteria also exist in the gut, and that in healthy 
individuals, approximately 15-30% of blood urea is degraded via gut bacteria into 
ammonia3, which returns to the liver via the portal vein, only to be recycled into urea. 
This percentage of degraded urea may even be greater in patients with urea cycle 
disorders, who are on a low protein-diet4 and whose gastrointestinal contents thus likely 
have lower nitrogen content, promoting bacterial recycling of nitrogen from available 
urea. Additionally, urea hydrolysis has been shown to be greatest in infants5, precisely 
the age at which hyperammonemic episodes are the most frequent in UCD patients. 
 
We intend to study if AHA can inhibit gut bacteria degradation of urea, thereby reducing 
the quantity of ammonia returning to the liver. We intend to investigate this by studying 
subjects on two occasions at least 3 days apart: 
 
On the first occasion, subjects will receive an intravenous dose of 13C-urea. Following 
the intravenous bolus of 13C-urea, over the subsequent 4 hours, we will collect several 
sequential measurements of blood and urine biomarkers from an IV catheter placed in 
the other arm. The intent is to obtain baseline 13CO2 kinetics in the subject.  
 
On the second occasion, subjects will first receive an oral dose of AHA approximately 1 
hour prior to the intravenous 13C-urea dose. Similar sequential measurements of blood 
and urine biomarkers will be performed. The intent is to observe a reduction in 13CO2 
when AHA is administered. 
 
We intend to initially study a cohort of unaffected adult subjects. If successful, we will 
study adults with partial urea cycle disorders.  
 


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This study will be conducted in the Clinical Research Center (CRC) of the Clinical and 
Translational Research Institute (CTSI) of Children’s National Medical Center (CNMC). 
2. Specific Aims (Hypothesis and Objectives) 
 
The specific aim is to investigate whether a single oral dose of AHA can inhibit intestinal 
bacterial urease in healthy subjects as well as in patients with partial UCDs, and 
whether it is safe. We propose a study with two components: the first without AHA, and 
the second after a single dose of AHA, 60mg/kg/d. We will evaluate whether AHA will 
inhibit bacterial urease, by measuring 13C-labeled urea in blood and urine samples, 
following an intravenous load of 13C-urea. Blood and urine 13C-urea, plasma ammonia, 
plasma glutamine and blood urea will also be measured. 
3. Background 
 
It is well known that gut commensal bacteria modulate nutrient absorption, mucosal 
barrier fortification, xenobiotic metabolism, angiogenesis, and intestinal maturation. The 
gut microbiome also interacts strongly with the host in determining metabolic 
phenotypes. Microbial metabolism and co-metabolism has been described for various 
nutrients and metabolic products including vitamins, lipids, fatty acids, organic acids and 
amino acids. Gut microbial metabolism also affects urea cycle function more directly by 
contributing to portal ammonia via exogenous and endogenous pathways that include: 
1) microbial breakdown of dietary protein and 2) the enzymatic hydrolysis of urea by 
urease to produce ammonia and carbonic acid. A number of gut dwelling bacteria 
produce urease including: Proteus species, Helicobacter pylori, and Klebsiella. Urea is 
transported from the blood to the intestinal lumen where it is hydrolyzed to ammonia by 
microbial urease. Studies in healthy human subjects indicate that up to 30% of liver-
synthesized urea may enter the intestine where it can be hydrolyzed by microbial 
urease to produce ammonia. It is estimated that 15-30% of the nitrogen derived from 
microbial urea hydrolysis is incorporated back into urea by the liver. This process of 
recycling of urea is known as urea nitrogen salvage (UNS). UNS may be dependent on 
protein intake as well as microbial populations. For example, subjects, such as UCD 
patients, on a low protein diet showed greater UNS compared to controls. Secondary 
effects of gut bacteria are evident in urea cycle enzyme activity. Germ-free mice have 
significantly lower Ornithine Transcarbamylase (OTC) activity, and decreased urea 
cycle intermediates ornithine and arginine. In addition, liver slices from germ-free mice 
synthesize less urea compared to their conventional controls. Overall gut microbes 
contribute up to 50% or more of the portal blood ammonia pool.  
 
Currently, the only approved clinical use of the drug for blockade of urease in 
bladder/renal proteus infections associated with renal struvite calculi (Lithostat, Mission 
Pharmacal, San Antonio, TX). The prescribing information indicates a recommended 
AHA dosing of 10-15 mg/kg/d (and 10 mg/kg/d in children), administered at 6-8 hour 
intervals when the stomach is empty. Children have tolerated a dose of 10 mg/kg/ 
satisfactorily for periods up to one year.  


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Enteral AHA has previously been administered to patients with hyperammonemia due to 
hepatic encephalopathy in two published reports6,7 A single dose of oral 750 mg in adult 
patients was insufficient to result in any change in ammonia after 90 minutes in cirrhotic 
subjects free of H. Pylori7. However, in encephalopathy cirrhotic subjects administered 
AHA 20-60 mg/kg via naso-gastric tube, a statistically significant decreased in blood 
ammonia was observed6, with the effect most striking in subjects receiving a dose of 40-
60 mg/kg/d. 
 
This proposal would introduce a novel therapeutic approach for patients with UCD using 
a low-toxicity compound that may be particularly effective in patients with partial UCDs. 
There are two potential ways this approach may lower blood ammonia or excess 
nitrogen. The first is through blockage of new ammonia formation from urease. The 
second path may be increased consumption of residual dietary nitrogen by the gut flora 
in the absence of available nitrogen released through urease. Both effects may 
decrease the amount of nitrogen entering the portal vein. This new therapy will not 
interfere with other therapies, but would be complementary to them and may potentiate 
the nitrogen trapping effects of arginine and citrulline by preventing the degradation of 
the urea produced by their administration. 
 
4. Study Design and Methods 
 
This pilot crossover study will first evaluate the impact of AHA versus non-AHA primarily 
on 13CO2 and secondarily on other biomarkers in healthy adults before applying the 
same crossover design to UCD subjects. A randomization table will determine if AHA or 
non-AHA will be performed first.  
The figure below illustrates our study design:  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Subjects will be required to fast for a minimum of 4 hours prior to beginning the study. 
Food consumption will not be permitted during the study; however subjects will be 
allowed to drink water or pedialyte throughout the study. Subjects will be observed and 


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various biomarkers will be collected throughout the 4-6 hours that they are studied. 5 
mL of blood will be collected at each of the 7 time points shown above.  Administration 
of [13C]-urea will be completed through an intravenous catheter. Blood draws will be 
done through the placement of a Heplock intravenous catheter on the opposite arm 
from where [13C]-urea was first administered. If there is not adequate vascular access, 
subjects will have a PICC (peripherally inserted central catheter) line placed instead. 
 
Recruitment and enrollment: See Section 4.3, 8.4-5 
Follow-up: Subjects will be followed throughout the duration of their participation.  
Data collection: See Sections 5.9, 6, 7 
4.1 Inclusion Criteria 
 
For healthy adults: 
- 
Ages 18-60 years 
- 
Compliant with receiving medications orally and intravenously  
- 
Compliant with providing blood and urine samples 
For UCD subjects: 
- 
Ages 18-60 years  
- 
Compliant with receiving medications orally and intravenously  
- 
Compliant with providing blood and urine samples 
- 
Participants should be diagnosed with one of the following 4 urea cycle 
disorders: 
o Carbamylphosphate synthetase I deficiency - decreased (less than 20 % 
of control) CPS I enzyme activity in liver or an identified pathogenic 
mutation 
o Ornithine Transcarbamylase deficiency- identification of a pathogenic 
mutation, linkage analysis in an affected family, less than 20% of control of 
OTC activity in the liver, or elevated urinary orotate (greater than 20 
µM/mM) following allopurinol loading with absence of argininosuccinic acid  
o Argininosuccinic acid synthetase deficiency (Citrullinemia) - greater than 
or equal to 10-fold elevation of citrulline in plasma, decreased AS enzyme 
activity in cultured skin fibroblasts or other appropriate tissue, or 
identification of a pathogenic mutation in the AS gene 
o Argininosuccinic acid lyase deficiency - presence of argininosuccinic acid 
in the blood or urine, decreased AL enzyme activity in cultured skin 
fibroblasts or other appropriate tissue, or identification of a pathogenic 
mutation in the AL gene 
 
4.2 Exclusion Criteria 
 
For healthy and UCD Patients: 
- 
Current or prior Helicobacter Pylori infection 
- 
Chronic gastrointestinal illness (e.g., inflammatory bowel disease) 
- 
Chronic renal failure 
- 
Taking probiotic medications within the week prior to the study 


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- 
Pregnant or lactating. Documentation of a negative pregnancy test within a 
week prior to testing is required, unless pre-menarchal or menopausal, 
experiencing menses that week, or other circumstances which preclude 
pregnancy (e.g. hysterectomy). 
- 
Presence of acute infection at the time of inclusion 
- 
Participation in any other clinical interventional trial or received experimental 
medication within the last 30 days 
- 
Any clinical or laboratory abnormality or medical condition that, at the 
discretion of the investigator, may put the subject at an additional risk by 
participating in this study 
4.3 Recruitment of Participants 
 
The institution conducting this study, Children's National Medical Center (CNMC), is a 
nation-wide referral center for patients with urea cycle disorders and other inborn errors 
of metabolism. Additionally, CNMC is the lead site of the Urea Cycle Disorders 
Consortium (UCDC), part of the Rare Diseases Clinical Research Network (RDCRN).  
UCDC members will refer potential participants to this trial.  In addition, the RDCRN-
UCDC has established a contact registry that informs registrants of clinical trials. We 
are in close contact with the National Urea Cycle Disorders Foundation (NUCDF), a lay 
organization dedicated to the promotion of treatment and research to improve the health 
of patients with urea cycle disorders. This organization helps with patient recruitment for 
these studies. Our professional relationship with each of these families is very strong 
and trusting. We have enrolled some of these patients previously in research studies. 
We anticipate no problem in accommodating the stipulated patient cohort (maximum of 
8 individuals total for the current project.  Thus, we hope to be able to recruit a sufficient 
number of participants (see power calculation and statistical considerations) for this trial 
both locally and nationally. 
 
The Washington DC area is comprised of a large diverse metropolitan population. We 
do not anticipate difficulty with recruitment of 8 healthy adult control subjects. 
4.4 Retention strategies 
 
As the study involves only 2 days of participation, we anticipate retention to be near 
100%. 
4.5 Data Elements 
 
In addition to the elements described in Table 1, the collected data elements will include 
age, sex, race, and ethnicity, as required by the NIH, as well as UCD diagnosis and 
method of diagnosis, if relevant. 
4.6 Schedule of Events 
 


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Subjects will be studied twice: once without and once with a single dose of 
acetohydroxamic acid, with the two study days at least 3-days apart. 
 
Table 1.  Laboratory investigations (each study day) 
 
Time point (min) 
 
Baseline
0
30
60
90
120
180
240
Blood [13C]-urea 
 
X 
X 
X 
X 
X 
X 
X 
Blood urea 
 
X 
X 
X 
X 
X 
X 
X 
Plasma glutamine 
 
X 
X 
X 
X 
X 
X 
X 
Ammonia 
 
X 
X 
X 
X 
X 
X 
X 
Blood 13CO2 
 
X 
X 
X 
X 
X 
X 
X 
 
 
 
 
 
 
 
 
 
Urine [13C]-urea 
 
X 
 
 
 
 
 
X 
Urine urea 
 
X 
 
 
 
 
 
X 
 
 
 
 
 
 
 
 
 
Safety labs: 
 
 
 
 
 
 
 
 
Hemoglobin 
X 
 
 
 
 
 
 
X 
White blood count 
X 
 
 
 
 
 
 
X 
Platelets 
X 
 
 
 
 
 
 
X 
 
 
 
 
 
 
 
 
 
AST 
X 
 
 
 
 
 
 
X 
ALT 
X 
 
 
 
 
 
 
X 
Bilirubin 
X 
 
 
 
 
 
 
X 
Creatinine 
X 
 
 
 
 
 
 
X 
‘Baseline’ indicates at a time 0 on days when AHA is not administered or at a time prior 
to AHA administration on the days where AHA is administered. In addition, some of the 
blood and urine samples will be saved at the Clinical and Translational Science Institute 
at CNMC for up to 3 years after the conclusion of the study to test for the metabolism of 
AHA, after which the samples will be discarded. 
 
5. Safety Monitoring 
 
5.0 Data and Safety Monitoring Plan 
 
The study protocol will be reviewed and approved by the National Institutes of Health 
(NIH) before submission to individual center IRBs for approval.  Participant enrollment 
may only begin with IRB approved consent forms. 
 
Adverse events are to be collected and reported to the Study Chair following each 
completed study, or in the case of a laboratory abnormality, when the abnormal 
laboratory result is identified. The Study Chair will also review the study adverse event 
data after completed enrollment of the 8 healthy subjects and 8 subjects with UCD.  
 


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The study protocol will be reviewed and approved by the Data Safety and Monitoring 
Board (DSMB) of the Rare Disorders Clinical Research Consortium of the National 
Institutes of Health (NIH) before submission to individual center IRB’s for approval.  
Participant enrollment may only begin with IRB approved consent forms.  
 
This is an interventional pilot study that meets the federal definition of more than 
minimal risk. 
 
5.1 Study Oversight 
 
The Study Chair has primary oversight responsibility of this clinical trial. The NIH 
appointed Data Safety Monitoring Board (DSMB) has oversight responsibility of the 
Data Safety Monitoring Plan (DSMP) for this clinical trial. The DSMB will review accrual, 
patterns and frequencies of all adverse events, protocol compliance every 6 months. 
The DSMB makes recommendations to the NIH regarding the continuation status of the 
protocol. 
 
Each site’s Primary Investigator and their research team (co-Investigators, research 
nurses, clinical trial coordinators, and data managers) are responsible for identifying 
adverse events. Aggregate report- detailed by severity, attribution (expected or 
unexpected), and relationship to the study drug/study procedures – will be available 
from the DMCC for site review.  Adverse events will be reviewed by the research team 
at the end of the study.   A separate report detailing protocol compliance will also be 
available from the DMCC for site review on a monthly basis. The research team will 
then evaluate whether the protocol or informed consent document requires revision 
based on the reports. 
 
5.2 Definitions and Standards 
 
The Rare Diseases Clinical Research Network defines an adverse event as:  “…an 
unfavorable and unintended sign, symptom or disease associated with a participant’s 
participation in a Rare Diseases Clinical Research Network study.” 
 
Serious adverse events include those events that:  “result in death; are life-threatening; 
require inpatient hospitalization or prolongation of existing hospitalization; create 
persistent or significant disability/incapacity, or a congenital anomaly/birth defects.”  
 
An unexpected adverse event is defined as any adverse experience…the specificity or 
severity of which is not consistent with the risks of information described in the protocol. 
Expected adverse events are those that are identified in the research protocol as having 
been previously associated with or having the potential to arise as a consequence of 
participation in the study 
 


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All reported adverse events will be classified using the Common Terminology Criteria 
for Adverse Events (CTCAE), developed and maintained by CTEP at National Cancer 
Institute. 
 
5.3 Expected/Known Risks/Discomforts/Adverse Events  
 
A definition of expected adverse events associated with study intervention and 
procedures are outlined below. 
 
Study Drug/Intervention: 
AHA: 
Acetohydroxamic acid has been an FDA approved medication for the treatment of 
struvite nephrolithiasis for over 25 years. According to the prescribing information, about 
150 patients, including children, have been treated, most for periods of more than 1 
year.  
 
Well controlled, long-term animal studies that identify the carcinogenic potential of AHA 
treatment have not been conducted. Acetamide, a metabolite of AHA, has been shown 
to cause hepatocellular carcinoma in rats at oral doses 1,500 times the human dose. 
AHA is cytotoxic and was positive for mutagenicity in the Ames test.  
 
The pharmacokinetics of AHA in man are well known: 36-65% of the oral dose of AHA 
is excreted unchanged in the urine. The plasma half-life of AHA is approximately 5-10 
hours in subjects with normal renal function. 
 
According to the AHA (Lithostat) prescribing information, adverse reactions have 
occurred in up to thirty percent (30%) of the patients receiving AHA. In some instances, 
the reactions were symptomatic: in others, only changes in laboratory parameters were 
noted. Adverse reactions seem to be more prevalent in patients with pre-existing 
thrombophlebitis and/or in patients with advanced degrees of renal insufficiency.  
 
The following reactions have been reported: 
- 
30% - Mild headaches during the first 48 hours of treatment, responsive to 
standard therapy 
- 
Tremulousness and nervousness 
- 
20%  - Gastrointestinal symptoms (nausea, vomiting, anorexia) 
- 
15% - laboratory findings characteristic of a hemolytic anemia 
- 
Non-pruritic, macular rash on the upper extremities and face, usually 
concomitantly with alcoholic beverages, with spontaneous resolution 
- 
Superficial phlebitis 
 
Acute toxicity has not occurred. Milder overdosages resulting in hemolysis have 
occurred in an occasional patient with reduced renal function after several weeks or 
months of continuous treatment. 
 


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There is a small risk that the blood ammonia level will rise during the study. This unlikely 
possibility, would mostly likely result from toxicity of the AHA to the liver.  
 
13C Urea: 
Urea, and by extension, its stable isotope [13C]-urea, is a substance regarded by the 
FDA to be generally regarded as safe (GRAS). Administration of a small amount of 
stable isotopic urea should not pose a risk to subjects with urea cycle disorders, as the 
amount of ammonia generated by its hemolysis would represent only a small fraction of 
the total body ammonia. 
 
There is a potential risk of contamination of the drug or isotope used in the study. 
However, a sterile and pyrogen-free preparation of the isotope is used, and the drug is 
manufactured via Current Good Manufacturing Practices (CGMP). 
 
Study Procedures:  
Venipuncture:  The placement of the two Heplock intravenous catheters for blood 
sampling and [13C]-urea administration could result in a bruise or infection at the site of 
insertion. The vein in which the needle has been inserted to draw blood may become 
sore and red.  A temporary “black and blue mark” may develop, and rarely fainting may 
occur. If a PICC line is inserted in the arm (by an interventional radiologist) intravenous 
sedation is given and involves risks of apnea or aspiration. There is also risk of vessel 
perforation and infection of the central line catheter.  
 
There is a risk of loss of confidentiality, which could affect insurability and result in 
stigmatization.  
 
5.4 Reporting Timeline 
 
 Within 24 hours (of learning of the event), investigators must report any reportable 
Serious Adverse Event (SAE) that: 
o 
Is considered life-threatening/disabling or results in death of subject 
-OR- 
o 
Is Unexpected/Unanticipated  
 Investigators must report all other reportable SAEs within 5 working days (of learning 
of the event). 
 All other (suspected) reportable AEs must be reported to the RDCRN within 20 
working days of the notification of the event or of the site becoming aware of the 
event. 
 
Local institutional reporting requirements to IRBs, any GCRC oversight committee and 
the FDA, if appropriate, remain the responsibility of the treating physician and the Study 
Chair. 
 


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5.5 RDCRN Adverse Event Data Management System (AEDAMS) 
 
Upon entry of a serious adverse event, the DMCC created Adverse Event Data 
Management System (AEDAMS) will immediately notify the Study Chair, site PIs, the 
Medical Review Officer, and any additional agencies of any reported adverse events via 
email.  
 
Serious adverse events: The NIH appointed Medical Review Officer (MRO) determines 
causality (definitely not related, probably not related, possibly related, probably related, 
definitely related) of the adverse event. The MRO may request further information if 
necessary and possibly request changes to the protocol or consent form as a 
consequence of the adverse event. A back-up notification system is in place so that any 
delays in review by the MRO beyond a specified period of time are forwarded to a 
secondary reviewer. The Adverse Event Data Management System (AEDAMS) 
maintains audit trails and stores data (and data updated) and communication related to 
any adverse event in the study.  
 
Non-serious expected adverse events: Except those listed above as immediately 
reportable, non-serious expected adverse events  that are reported to or observed by 
the investigator or a member of his research team will be submitted to the DMCC in a 
timely fashion (within 20 working days). The events will be presented in tabular form 
and given to the MRO and RDCRN DSMB on a bi-annual basis. Local site investigators 
are also required to fulfill all reporting requirements of their local institutions. 
 
The DMCC will post aggregate reports of all adverse events (serious/not serious and 
expected, unexpected) for site investigators and IRBs. 
 
5.6 Study Discontinuation  
 
The NIH, RDCRN DSMB and local IRB's (at their local site) have the authority to stop or 
suspend this trial at any time. This study may be suspended or closed if: 
 Accrual has been met 
 The study objectives have been met 
 The Study Chair / Study Investigators believe it is not safe for the study to 
continue 
 The RDCRN DSMB suspends or closes the trial 
 The NIH suspends or closes the trial 
 The FDA suspends or closes the trial 
 
5.7 Subject Discontinuation 
 
An intent-to-treat approach will be used. All data acquired prior to termination for the 
reasons outlined below will be included in the primary analysis unless patient withdraws 


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consent. Every effort will be made to conduct a final study visit with the participant and 
participants will be followed clinically until, if applicable, all adverse events resolve.  
 
 Withdrawal by the participant 
 Withdrawal by the investigator 
 Intercurrent illness or event that precludes further visits to the study site or ability 
to evaluate disease (e.g.-mental status change, large pleural effusion).  
 
5.8 Data Quality and Monitoring Measures 
 
As much as possible data quality is assessed at the data entry point using intelligent on-
line data entry via visual basic designed screen forms. Data element constraints, 
whether independent range and/or format limitations or ‘relative’ referential integrity 
limitations, can be enforced by all methods employed for data input. QA reports assess 
data quality post-data entry. As we note, data quality begins with the design of the data 
collection forms and procedures and incorporates reasonable checks to minimize 
transcription and omission errors.  Of the more important quality assurance measures 
are the internal validity checks for reasonableness and consistency.  
 
 Data Monitoring: The RDCRN DMCC identifies missing or unclear data and 
generates a data query to the consortium administrator contact.  
 Data Delinquency Tracking: The Data Management and Coordinating Center will 
monitor data delinquency on an ongoing basis.   
 
6. Statistical Considerations 
 
Linear longitudinal regression models will be developed to estimate the change in the 
time-averaged levels of blood 13CO2 (primary endpoint), as well as blood levels of [13C]-
urea, ammonia and glutamine after AHA versus after non-AHA. When we evaluate the 
effect of AHA on each metabolite, the model will control for each metabolite’s 
pretreatment level and will adjust variance estimates to account for the correlation 
between measurements on the same person as well as to take account of the random 
effect on the intercept. We will consider a relative AHA versus non-AHA difference in 
the time-averaged level of 13CO2 of at least 20% as a signal that AHA can effectively 
reduce the impact of gut bacteria on urease activity. The presence of a clear 
effectiveness signal in healthy adults will be required before the crossover study can be 
implemented in adults with UCD.  
 
Pilot data indicates that the expected level 13CO2 in the absence of AHA treatment is 
0.041% with a conservative precision of +/- 0.0075%.  Therefore, using the sampsi 
procedure in Stata 12, a sample size of 8 crossover participants provides 90% power in 
2-tailed testing at an alpha of 0.05 to detect a 20% relative (0.041% versus 0.033%) 


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difference in the time-averaged level of 13CO2 on AHA versus non-AHA in either healthy 
or UCD affected adults.   
7. Data Management 
 
All study data will be collected via systems created in collaboration with the RDCRN 
Data Management and Coordinating Center and will comply with all applicable 
guidelines regarding patient confidentiality and data integrity. Data will be entered 
online, and submitted to the DMCC-managed UCDC RDCRN portal. 
 
Blood and urine samples are to be collected on each study day and sent to the 
Children’s Hospital of Philadelphia for stable-isotope analysis of 13CO2 and 13C-urea. As 
the number of enrollees is small, samples will be tracked via courier and email 
communication between CNMC and CHOP.  
 
Samples may be kept for up to 3 years after the completion of the study, after which 
they will be discarded.  
7.1 Registration 
 
Registration of participants on this protocol will employ an interactive data system in 
which the clinical site will attest to the participant’s eligibility as per protocol criteria and 
obtain appropriate informed consent. IRB approval for the protocol must be on file at the 
DMCC before accrual can occur from the clinical site. 
 
The DMCC will use a system of coded identifiers to protect participant confidentiality 
and safety.  Each participant enrolled will be assigned a local identifier by the enrollment 
site.  This number can be a combination of the site identifier (location code) and a serial 
accession number.  Only the registering site will have access to the linkage between 
this number and the personal identifier of the subject.  When the participant is registered 
to participate in the study, using the DMCC provided web-based registration system, the 
system will assign a participant ID number.  Thus each participant will have two codes: 
the local one that can be used by the registering site to obtain personal identifiers and a 
second code assigned by the DMCC.  For all data transfers to the DMCC both numbers 
will be required to uniquely identify the subject.  In this fashion, it is possible to protect 
against data keying errors, digit transposition or other mistakes when identifying a 
participant for data entry since the numbers should match to properly identify the 
participant.  In this fashion, no personal identifiers would be accessible to the DMCC.  
 
7.2 Data Entry 
 
Data collection for this study will be accomplished with online electronic case report 
forms.  Using encrypted communication links, on-line forms will be developed that 
contain the requisite data fields.   


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7.3 Data Quality Control 
 
As much as possible data quality is assessed at the data entry point. Data element 
constraints, whether independent range and/or format limitations or 'relative' referential 
integrity limitations, can be enforced by all methods employed for data input. QA reports 
assess data quality post-data entry. As we note, data quality begins with the design of 
the data collection forms and procedures and incorporates reasonable checks to 
minimize transcription and omission errors.  Of the more important quality assurance 
measures are the internal validity checks for reasonableness and consistency.  In 
addition to those described above, we propose to build these checks into the initial 
tables and cross tabulations that should reveal any remaining data quality issues. 
 
7.4 Laboratory data flow 
 
This study intends to collect a small number of samples on a small number of subjects.  
Some samples will be shipped via courier to Children’s Hospital of Philadelphia. Given 
the trivial number of samples exchanged, online courier tracking and email exchange 
will be sufficient to ensure sending and receipt of samples.  
 
7.5 Study Records Retention 
 
Study records will be maintained for at least three years from the date that the grant 
federal financial report (FFR) is submitted to the NIH. 
 
7.6 Protocol Deviations 
 
A protocol deviation is any noncompliance with the clinical study protocol, Good Clinical 
Practice, or Manual of Procedures requirements.  The noncompliance may be on the 
part of the subject, the investigator, or study staff.  As a result of deviations, corrective 
actions are to be developed by the study staff and implemented promptly. 
 
All deviations from the protocol must be addressed in study subject source documents 
and promptly reported to the DMCC, Study Chair, and the local IRB, according to their 
requirements.   


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8. Human Subjects 
8.1 GCP Statement 
 
This clinical trial will be conducted in accordance with the ethical principles that have 
their origin in the Declaration of Helsinki, and that are consistent with Good Clinical 
Practice and all applicable regulatory requirements. 
 
8.2 Benefits  
 
8.2.1 Potential Benefits of the Proposed Research to Subjects and Others   
 
Subjects will be compensated for their participation in the study, and will receive $500 
for completion of the study ($250 per day).  
 
Additionally, if the proposed studies show that the use of AHA is effective in reducing 
hyperammonemia and increasing urea excretion in patients with urea cycle disorders, 
these patients can be treated for their deficiency long-term with the use of this new 
specific therapeutic agent pending regulatory approval. Thus, there can be an important 
direct benefit for these participants. If the proposed study and the underlying hypothesis 
are correct this study could improve the medical condition of some or all of the patients 
also prevent life-threatening events in those who respond. At this stage, the patients will 
have the option to be treated under a different specific IND obtained by their local 
physician or enroll in a long-term study if one is available.  Thus, this significant 
potential benefit balances the relatively low risks of the study. 
 
8.2.2 Importance of the Knowledge to Be Gained 
 
The study will provide the first reliable information of whether AHA could potentially 
reduce the hyperammonemia associated with urea cycle disorders.  Such knowledge 
could provide an additional treatment for hyperammonemia in these conditions. In 
addition, the information gained could also be relevant to better understanding the 
regulation of the urea cycle which may impact also treatment of hyperammonemia due to 
liver disease. 
8.3 Recruitment  
 
 
Children’s National is a nation-wide referral center for patients with urea cycle disorders, 
and the lead site for the Urea Cycle Disorders Consortium. In addition, to recruiting 
patients with urea cycle disorders, our recently funded RDCRC-UCD has a centralized 
registry, where patients are invited to enroll in clinical trials. We are in close contact with 
the National Urea Cycle Disorders Foundation, a lay organization dedicated to the 
promotion of treatment and research to improve the health of patients with urea cycle 
disorders. The NUCDF will help with patient recruitment for these studies. 
 


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Inclusion of women and minorities 
The urea cycle disorders studied in this trial involve both genders equally and all ethnic 
groups are affected to the best of our knowledge.  Thus, there will not be exclusion of 
either gender or any ethnic group.  The investigators of this study plan to make a 
special effort to enroll subjects from various ethnic groups in proportions consistent with 
their proportion in the general populations.  The Washington D.C. metropolitan areas 
have large minority groups reflected also by their proportions in the patients seen at 
Children’s National.  We believe that the study will have adequate representation by 
women and minority groups. 
 
The cohort of unaffected control subjects will be adults only, as participation in this trial 
will not confer any direct benefit to unaffected children. 
 
8.4 Written Informed Consent 
 
Written informed consent will be obtained from each participant before any study-
specific procedures or assessments are done and after the aims, methods, anticipated 
benefits, and potential hazards are explained.  The participant’s willingness to 
participate in the study will be documented in writing in a consent form, which will be 
signed by the participant with the date of that signature indicated.  The investigator will 
keep the original consent forms and signed copies will be given to the participants.  It 
will also be explained to the participants that they are free to refuse entry into the study 
and free to withdraw from the study at any time without prejudice to future treatment.  
Written and/or oral information about the study in a language understandable by the 
participant will be given to all participants. 
 
8.5 Process of Consent 
 
Healthy adult control subjects will be recruited from the Washington DC metropolitan 
area. The study may be advertised on the campus of some local universities.  
 
Participants with UCDC will be recruited from the metabolism clinics of Children’s 
National, or through the Urea Cycle Disorders Consortium. Alternatively, patients will be 
notified of the study by a collaborating lay organization, the National Urea Cycle 
Disorders Foundation.  
 
Informed consent will be obtained by one of the investigators of the study before the 
study can begin. The participants will receive a copy of the consent before the formal 
informed consent process takes place at the clinic or at the CRC. Consent forms will be 
signed by all participants (and legal guardian when appropriate) and the consent 
process will be documented in the patient's chart. The Research Subject Advocates of 
the CRCs will be present during some administrations of informed consent in this trial 
participating sites in order to assure that the informed consent process is conducted 
according to the highest ethical standards. 


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8.6 Certificate of Confidentiality 
 
To help protect participant privacy, a Letter of Confidentiality has been obtained from 
the National Institutes of Health (NIH).  With this Certificate, the researchers cannot be 
forced to disclose information that may identify a study participant, even by a court 
subpoena, in any federal, state, or local civil, criminal, administrative, legislative, or 
other proceedings.  The researchers will use the Certificate to resist any demands for 
information that would identify a participant, except as explained below. 
 
The Certificate cannot be used to resist a demand for information from personnel of the 
United States Government that is used for auditing or evaluation of federally funded 
projects or for information that must be disclosed in order to meet the requirements of 
the federal Food and Drug Administration (FDA). 
 
Even with the Certificate of Confidentiality, the investigators continue to have ethical 
and legal obligations to report child abuse or neglect and to prevent an individual from 
carrying out any threats to do serious harm to themselves or others.  If keeping 
information private would immediately put the study participant or someone else in 
danger, the investigators would release information to protect the participant or another 
person. 
 
Department of Health and Human Services (DHHS) personnel may request identifying 
information for purposes of performing audits, carrying out investigations of DHHS grant 
recipients, or evaluating DHHS funded research projects. 
 
9. References 
 
1. 
Feldman S, Putcha L, Griffith DP. Pharmacokinetics of acetohydroxamic acid. 
Preliminary investigations. Investigative urology 1978;15:498-501. 
2. 
Putcha L, Griffith DP, Feldman S. Pharmacokinetics of acetohydroxamic acid in 
patients with staghorn renal calculi. European journal of clinical pharmacology 
1985;28:439-45. 
3. 
Jackson AA, Danielsen MS, Boyes S. A noninvasive method for measuring urea 
kinetics with a single dose of [15N15N]urea in free-living humans. The Journal of 
nutrition 1993;123:2129-36. 
4. 
Danielsen M, Jackson AA. Limits of adaptation to a diet low in protein in normal 
man: urea kinetics. Clin Sci (Lond) 1992;83:103-8. 
5. 
Steinbrecher HA, Griffiths DM, Jackson AA. Urea production in normal breast-fed 
infants measured with primed/intermittent oral doses of [15N, 15N]urea. Acta Paediatr 
1996;85:656-62. 


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6. 
Summerskill WH, Thorsell F, Feinberg JH, Aldrete JS. Effects of urease inhibition 
in hyperammonemia: clinical and experimental studies with acetohydroxamic acid. 
Gastroenterology 1968;54:20-6. 
7. 
Zullo A, Rinaldi V, Hassan C, et al. Helicobacter pylori and plasma ammonia 
levels in cirrhotics: role of urease inhibition by acetohydroxamic acid. Italian journal of 
gastroenterology and hepatology 1998;30:405-9. 
 
10. Appendices and RDCRN Informed Consent Templates 
10.1 Appendix 
 
Drug Information: 
 
Acetohydroxamic acid (Lithostat) 
 
Pharmacology and Pharmaceutical Information:  
 
Acetohydroxamic acid (AHA) is a stable, synthetic compound derived from 
hydroxylamine and ethyl acetate.  It is a urease inhibitor that reversibly inhibits bacterial 
enzyme urease, thereby inhibiting the hydrolysis of urea and production of ammonia in 
urine infected with urea-splitting organisms.  AHA is available for oral administration as 
250 mg white, round tablets and manufactured by Mission Pharmacal. The intact drug is 
stored at controlled room temperature (2025oC) 
 
Treatment Information: 
 
All subjects (healthy adults and UCD patients) will receive a single oral dose of 60 
mg/kg acetohydroxamic acid during one of the treatment periods, based on the 
randomization assignment determining whether treatment occurs in the first or the 
second treatment cycle; doses will be rounded “up” or “down” to the nearest 250 mg to 
coincide with the available dosage form since the tablets cannot be scored.  Patients 
will be instructed to fast for 4 hours prior to the study; subsequently, the 13C-Urea tracer 
will be administered 60 minutes after the ingestion of the acetohydroxamic acid dose. 
 
13C-Urea 
13C-Urea is a stable isotope produced by Cambridge Isotope Laboratories, Inc., 
Tewksbury, MA.  The GMP grade pharmaceutical product is provided to Children’s’ 
National Medical Center as a sterile bulk powder. 
 
Treatment Information: 
All subjects (healthy adults and UCD patients) will receive a single IV infusion of 13C-
Urea administered over 10-15 minutes, during both treatment cycles.  The infusion will 
be prepared at a dose of 6 mg/kg and infused via a peripheral IV.  
 
Preparation of 13C-Urea for Intravenous Use 


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Per USP 797 guidelines, the preparation of a compounded sterile product (CSP) 
prepared from a powder and intended for intravenous use, represents a high-risk level 
condition/preparation. USP 797 regulations require a filtration sterilization process 
utilizing a 0.22 micron negatively charged filter for such high-risk procedures; the use of 
the specific sterilizing filter ensures sterility by minimizing bacterial particulates and 
endotoxins that may be associated with the use of compounding products that are not 
intended for sterile routes of administration. Additionally, the USP 797 regulations state 
that for a sterilized high-risk level preparation, in the absence of a sterility test, the 
storage period cannot exceed 24 hours when stored at controlled room temperature.  
Therefore, subject-specific infusions are prepared on the day of treatment. Per USP 797 
regulations, preparations compounded as single dose/single use and not prepared in 
groups of more than 25 identical individual single-dose packages are exempt from 
additional bacterial endotoxin testing. 
 
Procedure for preparing IV  13C-Urea Infusion 
 
All compounding of a CSP will be performed in USP 797 compliant hood following 
aseptic procedures 
1.  Weigh out appropriate amount of C-13 Urease from bulk container 
2.  Mix measured powder with 100 mL of 0.9% sodium chloride 
3.  Swirl to ensure powder is completely in solution 
4.  Draw up solution into syringe 
5.  Attach 0.2 micron disk filter* to syringe 
6.  Attach fluid dispensing connector to other end of filter 
7.  Attach new receiving syringe on other end of fluid dispensing connector  
8.  Pass solution through sterilizing disk filter into receiving syringe 
9.  Remove syringe containing sterilized solution and visually examine solution for the 
presence of particulate matter 
10.  All CSPs prepared in this manner will have a beyond-use date (BUD) of 24 hours 
when stored at room temperature 
 
*Mustang E Membrane Acrodisc Capsule disposable single use 0.2 micron filter is used 
to remove bacteria and particulates, as well as, endotoxins. The manufacturer (Pall 
Corporation) confirmed that this is the most appropriate filter to fulfill this sterilization 
process. 
 
Storage 
Both the acetohydroxamic acid tablets and 13C-urea powder is stored in the 
investigational Drug Service (IDS) pharmacy. The IDS pharmacy is a temperature 
controlled, limited access area restricted to pharmacy personnel only.  Both products 
are stored at controlled room temperature (2025°C). 
 
Accountability 


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A drug accountability record will be maintained for both the acetohydroxamic acid 
tablets and 13C-urea powder to reflect the day of treatment, the subject/patient’s initials 
and study ID number, the dose dispensed, and the lot number of the product dispensed. 
 
10.2 Informed Consent for Healthy Volunteers 
 
 
 
CHILDREN'S NATIONAL MEDICAL CENTER 
Center for Genetics 
111 Michigan Avenue, NW 
Washington, DC 20010 
(202) 476-5000 
 
Consent/Parental Permission to Participate in a Clinical Research Study and 
Authorization to Use Protected Health Information 
 
TITLE OF STUDY:  
 
 
Manipulating the Gut Microbiome 
PRINCIPAL INVESTIGATOR: 
 
Nicholas Ah Mew, MD, Genetic Medicine 
 
 
 
 
 
 
Marshall Summar, MD, Genetic Medicine 
 
Throughout this document, “You” always refers to the person who takes part in the 
study. 
 
Introduction 
 
We are inviting you to be part of a research study at Children’s National Medical Center 
(Children’s National).  Before you decide if you would like to participate, we want you to 
know why we are doing the study.  We also want you to know about any risks (anything 
unexpected that might happen) and what you will be expected to do in the study.  
 
This form gives you information about the study.  Your study doctor or a member of the 
research team will talk to you about the study and answer all of your questions.  We 
encourage you to discuss this study with your family and anyone else you trust before 
making your decision.  You must sign this form if you agree to take part in the study.  We 
will give you a signed copy of this form to keep.  
 
Your participation in this research is voluntary. 
  
You should only take part in this study if you want to volunteer.  You should not feel that 
there is any pressure to take part in the study to please the study doctor or the research 
staff.  You are free to participate in this research or withdraw at any time.  If you 
withdraw, your information will remain confidential. You will not have to complete the 
study and we will follow up with you as needed.  
 


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The Principal Investigator may remove you from the study if you cannot complete the 
study procedures. 
You will be told of any findings that are discovered while you are doing the research 
study.   
 
There will be no penalty or loss of benefits to which you are otherwise entitled if you 
decide not to be in the study or withdraw from the study later.   
 
This means that: 
You do not have to join the study. 
You may change your mind and stop being in the study at any time. 
We will tell you if we make any important changes to the study or if there are any 
important new findings so that you can decide if you still want to be in the study. 
   
If you are an employee or a medical or graduate student in training at Children’s National, 
your decision to participate or not participate will not affect your employment or academic 
standing.    
 
Why is this research study being done? 
 
Purpose of the study 
 
You are being asked to take part in a research study. The purpose of this study is to 
evaluate the drug, Lithostat (AHA or acetohydroxamic acid). We want to see if this drug 
is safe and effective for patients with a rare disease called urea cycle disorder (UCD). 
You are being asked to participate in this study because it will help find better 
treatments for patients with UCDs. Individuals with UCD cannot remove ammonia, a 
waste product, from the blood. We hope that this drug will decrease the production of 
ammonia to help patients with UCDs. About 16 people will take part in this study. 
 
You are being asked to be in the study because you met the proper criteria for eligibility 
and ineligibility after being asked a questionnaire.  
 
Lithostat is approved by the Food and Drug Administration for kidney stones. We now 
use other medications to help treat UCDs, but think that Lithostat will also be able to 
help patients with UCDs. Lithostat is an Investigational New Drug by the Food and Drug 
Administration (experimental drug).  It has been tested in adults and children in the past 
to help with kidney stones and was successful. We want to see if using Lithostat can be 
a useful addition to current treatments for urea cycle disorders in adults and children. 
 
The study will involve up to about 16 participants at 1 site nationally. All 16 participants will 
be recruited at Children’s National. 
 
Dr. Nicholas Ah Mew is the person responsible for this research study at Children’s 
National. He is called the Principal Investigator. 
 


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The NIH is paying for this research to be done. A drug company, Mission Pharmacal, is 
providing the Lithostat free of charge. 
 
What will happen in this research study? 
 
Phone screening and consent: 
If you decide to be part of this study, we will look at your medical records and collect 
your medical history. We will ask you several questions about your health, current 
medical conditions and medications to see if you are eligible to participate in this study. 
You will be informed if you are not eligible to participate in this study based off of the 
questions asked. Females: you will be asked to take a pregnancy test to make sure that 
you are not pregnant prior to starting the study. There are no direct benefits to 
participating in this study; however, your participation could help create new therapies 
for patients with urea cycle disorders. Consent will be confirmed in person the day of or 
up to a week before the start of the study. There are two study days. The study days 
must be at least 3 days apart and will take about 4-6 hours on each day. You will not 
know which day you are receiving the drug.  
 
Study day (without drug): 
We will have you fast for 4 hours prior to your appointment. When you come in that 
morning, we will take a blood sample (one venipuncture and then the IV catheter remains 
in place for the next 4 hours) and a urine sample. Safety labs are included at the start of 
the study. The blood test will take 5 mL/1 tsp. .  
 
You will then be given a single dose of 13C-urea through a different IV which will be 
inserted into  the opposite arm and removed after administration of the 13C-urea. 13C-
urea is a tracer that we can see throughout your body in your blood and urine for the tests 
that we will do. The tracer is for research purposes. There is no known risk of using this 
tracer as it exists in nature and in the human body. Urea is considered by the FDA to be 
generally recognized as safe (GRAS) in multiple food products.  
 
We will observe you for 4 hours after you get the tracer. During this time, the original IV 
catheter will remain in place so that we can take 6 more blood samples (each will be 5 
mL/1 tsp.). Another urine sample will be needed at the end of the 4 hours. We will also 
measure 13C urea levels in your blood and urine and 13CO2 levels in your blood. Safety 
labs are included at the end of the 4 hours. You will not be able to eat during the study, 
but can drink water and/or pedialyte if necessary. This will conclude the study day 
without the drug. 
 
Study day (with drug):  
The next appointment will have to be at least 3 days after the first one. Again, you will 
need to fast for 4 hours prior to your appointment. You will receive the experimental drug 
on this day. Safety labs will be collected prior to you receiving the Lithostat (experimental 
drug). We will give you one dose of the experimental drug, Lithostat. Lithostat has been 
approved by the FDA and used in patients with kidney stones for over 25 years. 1 hour 
after you take the Lithostat, we will take a blood sample (one venipuncture and then the 


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IV catheter remains in place for the next 4 hours) and a urine sample. The blood test will 
take 5 mL/1 tsp.. 
 
You will then be given a single dose of 13C-urea through a different IV which will be 
inserted into the opposite arm and removed after administration of the 13C-urea. We will 
observe you for 4 hours after you get the tracer. During this time, the IV catheter will 
remain in place so that we can take 6 more blood samples (each will be 5 mL/1 tsp). 
Another urine sample will be needed at the end of the 4 hours. We will alsomeasure13C 
urea levels in your blood and urine and 13CO2 levels in your blood. Safety labs are 
included at the end of the 4 hours. You will not be able to eat during the study, but can 
drink water and/or pedialyte if necessary. This will conclude the study day with the drug. 
 
 
The studies will be conducted at the Clinical Research Center at Children's National 
Medical Center in Washington, DC. Below is a timeline of what was just explained 
above: 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Below is a table that gives you more information about what we will be measuring in your 
blood and urine during the study: 
Time point (min)
 
Baseli
ne
0 
30 
60 
90 
120 
180 
240 
Blood [13C]-urea
X
X
X
X
X
X
X
Blood urea
X
X
X
X
X
X
X
Plasma glutamine
X
X
X
X
X
X
X
Ammonia
X
X
X
X
X
X
X
Blood 13CO2
X
X
X
X
X
X
X
Urine [13C]-urea
X
X


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Time point (min)
 
Baseli
ne
0 
30 
60 
90 
120 
180 
240 
Urine urea
X
X
Safety labs:
Hemoglobin
X
X
White blood count
X
X
Platelets
X
X
AST
X
X
ALT
X
X
Bilirubin
X
X
Creatinine
X
X
‘Baseline’ indicates at a time 0 on days when Lithostat is not administered or at a time 
prior to Lithostat administration on the days where it is administered. 
 
Is it O.K. to take other medications, dietary supplements, or alternative medicines while I 
am in this research study? 
 
There are many drugs (prescription and over-the-counter) and dietary supplements 
(including what are sometimes called “complementary” or “alternative” remedies) that 
might interact with the experimental study drug(s). Tell the study doctor about all of the 
medications and supplements you are currently taking. The study doctor will review all of 
these with you and decide if you can participate in the study. Also, you should not take 
any new medications or dietary supplements without discussing it with the study doctor 
first. 
 
How long will my participation in the research study last? 
 
You will have one appointment to determine if you are eligible to participate in the study. 
There will be two study days if you are eligible, which must be at least 3 days apart. You 
should tell us if you decide to drop out of the study. 
 
-There are any unexpected side effects 
 
-Your study doctor and/or the Sponsor of the study think it is in your best interest 
 
What are the risks and possible discomforts from being in this research study? 
 
Lithostat (acetohydroxamic acid/AHA) 
According to the Lithostat prescribing information, adverse reactions have occurred in 
up to 30/100 of the patients receiving Lithostat. In some cases, the reactions produced 
symptoms: in others, only changes in laboratory measurements were noted. Adverse 
reactions seem to be more common in patients with pre-existing thrombophlebitis 
and/or in patients with advanced kidney problems.  


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Lithostat has been an FDA approved medication for the treatment of kidney stones for 
over 25 years. According to the prescribing information, about 150 patients, including 
children, have been treated, most for periods of more than 1 year.  
 
The following reactions have been reported: 
~30/100 - Mild headaches during the first 48 hours of treatment, responsive to usual 
therapy 
Tremulousness and nervousness 
~20/100 - Gastrointestinal symptoms (nausea, vomiting, anorexia) 
~15/100 - laboratory findings characteristic of a hemolytic anemia (low iron from 
breaking down blood cells) 
Non-itchy, macular (red and bumpy) rash on the upper body and face, usually 
associated with alcoholic beverages, improved on its own 
Superficial phlebitis (inflamed vein) 
 
Acute toxicity has not occurred. Milder overdosages resulting in hemolysis (destruction 
of red blood cells) have occurred in an occasional patient with reduced kidney function 
after several weeks or months of continuous treatment. This is very unlikely to occur 
since you will only receive a single dose of the medication. 
We do not know any information about the carcinogenic (cancer causing) potential of 
Lithostat since many people haven’t studied it. Acetamide is a chemical produced when 
Lithostat is broken down. Acetamide has been shown to cause hepatocellular 
carcinoma (liver cancer) in rats at oral doses 1,500 times the human dose. Lithostat is 
cytotoxic (toxic to living cells) and can produce mutations in DNA. 
 
There is a small risk that the blood ammonia level will rise during the study. This unlikely 
possibility, would mostly likely result from toxicity of Lithostat to the liver. We will monitor 
this throughout the study. 
 
[13C]-urea is a substance regarded by the FDA to be generally regarded as safe 
(GRAS). Taking a small amount of this drug should not pose a risk to subjects with urea 
cycle disorders. The amount of ammonia generated by it would be very small compared 
to the ammonia already in the body. There is no known risk of using stable isotopes (the 
13C-urea) as they exist in nature and in the human body. Urea is considered by the FDA 
to be generally recognized as safe (GRAS) in multiple food products. 
There is a potential risk of contamination of the drug or isotope used in the study. 
However, a very careful sterile and pyrogen-free preparation of the isotope is used, and 
the drug is manufactured via Current Good Manufacturing Practices (CGMP). 
 
Study Procedures:  
Venipuncture:  The vein in which the needle has been inserted to draw blood may 
become sore and red.  A temporary “black and blue mark” may develop, and rarely 
fainting may occur. The placement of the Heplock intravenous (IV) catheter for blood 
sampling could result in a bruise or infection at the site of insertion and might cause 
discomfort.  
 


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There is a risk of loss of confidentiality, which could affect insurability and result in 
stigmatization. We will do our best to keep this information safe and private for your 
protection. 
 
We do not know if you will have all, some, or none of the possible risks, side effects, or 
discomforts. You should tell the study doctor, Dr. Nicholas Ah Mew, about any illness, 
side effect or discomfort that you have right away, even if it is not one of the things 
listed, or even if you think it is not related to the study. 
We will look for side effects when we examine you. The study doctor may have to lower 
the amount or stop giving the drugs if the side effects are serious. 
There may be risks we don’t know about. 
 
For female participants: Are there additional risks if I get pregnant or breastfeed my baby?  
 
The Lithostat used in this research study may have an effect on an unborn baby. You 
should not become pregnant or breast feed your baby while you are participating on this 
study.  If you are sexually active and are at risk of getting pregnant, you and your male 
partner(s) must use an effective method to avoid pregnancy or you must not have sex.   
 
The study doctor will talk to you about acceptable methods to avoid pregnancy while 
you are taking part in this study.  You will have to use the chosen method to avoid 
pregnancy or abstain (not have sexual intercourse) during your participation.  
 
Natural family planning methods (such as the rhythm method) will not be a permissible 
means of avoiding pregnancy during study participation.  If you have questions about 
this or want to change your method to avoid pregnancy, please ask the study doctor.  If 
you become pregnant during the research study, please tell the study doctor 
immediately. 
 
If you are breastfeeding a baby, the drugs used in this research could pass into the 
breast milk. You should not breastfeed your baby while you are participating in this 
study. You may need to continue to avoid breastfeeding even after your participation in 
the study is over.  Talk to the study doctor about the length of time you need to avoid 
breastfeeding. 
 
For male participants: Are there additional risks if I father a baby?  
 
The Lithostat used in this research study can damage sperm. You should not father a 
child while you are participating on this study because the Lithostat may indirectly affect 
an unborn child.  If you are sexually active and are at risk of causing a pregnancy, you 
and your female partner(s) must use an effective method to avoid pregnancy or you 
must not have sex.  The study doctor will talk to you about acceptable methods to avoid 
pregnancy while you are taking part in this study. You will have to use the chosen 
method to avoid pregnancy or abstain (not have sexual intercourse) during your 
participation.  
 


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Natural family planning methods (such as the rhythm method) will not be a permissible 
means of avoiding pregnancy while you are taking part in this study. If you have 
questions about this or want to change your method to avoid pregnancy, please ask the 
study doctor.  If your partner becomes pregnant during the research study, please tell 
the study doctor immediately. 
 
What are the possible benefits from being in this research study? 
 
You will not benefit directly from participating in this research study. The things we learn 
from you taking part might help other people with urea cycle disorders in the future by 
providing them with more treatment options. 
 
Alternatives: What other choices do I have if I don’t want to take part in the study? 
 
If you do not want to participate in the study, there are no other choices except not to 
take part. 
 
Will it cost me anything to take part in the study? 
 
There are no costs to you or your insurance company to participate in this study. 
Children’s National Medical Center will give you the medicine used in this study at no 
cost to you. You will not be charged for anything else we do that is part of the study. 
 
Compensation: Will I be paid for taking part in this study? 
 
You may receive up to a total of $500 after finishing this research study. The payment 
will be made in installments: [$250 for visit one, $250 for visit two]. You will be given a 
voucher to exchange for cash at the Children’s National cashier office each time you 
complete these visits.  We will also pay for your transportation to and parking at 
Children’s National when you are here to take part in the study. 
 
The Internal Revenue Service requires that any monetary payments totaling $600 or 
more in a calendar year must be reported for tax purposes. 
 
ClinicalTrials.gov 
 
A description of this clinical trial will be available on http://www.ClinicalTrials.gov, as 
required by U.S. law.  This Web site will not include information that can identify you.  At 
most, the Web site will include a summary of the results.  You can search this Web site at 
any time. 
 
How will you protect my privacy if I take part in this study? 
Who will see the information that I give you? 
 


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We will keep your study records confidential.  However, certain people may need to see 
your study records.  By law, anyone who looks at your records must keep them 
completely confidential.   
If you decide to take part in this study, only the people working on the study will know 
your name.  They will keep this information [e.g., so that we can contact you to schedule 
future appointments; in case we have to find you later to let you know of any new 
information that may affect your health].  Your personal information will not be given to 
anyone unless we get your permission in writing or if the law requires it.  This 
information will also only be given for regular hospital care, payment, and hospital 
management activities.  We will make every effort to keep your information private, but 
no one’s privacy can be totally guaranteed. 
Your medical record is confidential but, just like any medical record, there are some 
exceptions under state and federal law. 
There are some government agencies or other groups that may check records that 
identify you without your permission. They might review the records of this study and 
your medical records to make sure we are following the law and protecting the 
participants in the study.  The agencies or groups who might see these records are:  the 
research team, the Office for Human Research Protections, Department of Health and 
Human Services (DHHS), Food and Drug Administration, the sponsor (NIH Rare 
Diseases Clinical Research Network, Mission Pharmacal), Data Management and 
Coordinating Center (Tampa, FL), National Institute of Child Health and Human 
Development (NICHD) Data Safety and Monitoring Board (DSMB), and the Institutional 
Review Board of Children's National Medical Center (the ethics board and their staff that 
reviewed and approved this research study). 
The results of this research may be presented at meetings or in publications. You will not 
be personally identified. 
 
Transfer of Data to DMCC and Federal data repository 
 
The clinical information collected for this study will be stored in a computer database at 
the Data Management and Coordinating Center at the University of South Florida in 
Tampa, FL and also sent to a Federal data repository. A data repository provides a way 
for researchers to store the information collected during the research study for future 
research studies. The data management center uses several layers of protection for the 
clinical data stored in its computer database. It meets all of the local and federal security 
requirements for research datacenters. Your information is stored only using a study ID. 
 
Certificate of Confidentiality  
 
Sometimes people tell us some very personal information about themselves when they 
participate in a study and it becomes part of their research record.  To help us protect your 
privacy, the investigators have obtained a Certificate of Confidentiality from the U.S. 
Department of Health and Human Services (DHHS).  
 
With this Certificate, the investigators cannot be forced (for example, by a court order or 
subpoena) to give information that may identify you in any federal, state or local civil or 


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criminal court, or in any administrative, legislative, or other proceedings.  At sometime, 
however, DHHS might request this information as part of a review of the study records and 
medical records to make sure we are following the law and protecting the people in the 
study, and to make sure our results are correct.  If this happens, we are required to give 
DHHS all of the information they request for their review.  
 
It is important that you know that a Certificate of Confidentiality does not stop you or a 
member of your family from voluntarily giving information to others about yourself or your 
taking part in this research.  You should also know that if an insurer or employer learns 
about your participation and you give them permission to receive research information 
about you, we cannot use the Certificate of Confidentiality to keep your information private 
from them.  This means that you must also actively protect your own privacy.  
 
Finally, it is important that you know that we are not prevented from taking steps to 
prevent serious harm to you or to others.  For example, if you or anyone else might be in 
danger, we will have to report this to the authorities and get emergency help if it is 
needed.    
 
 
The Certificate cannot be used to resist a demand for information from personnel of the 
United States Government that is used for auditing or evaluation of Federally funded 
projects or for information that must be disclosed in order to meet the requirements of 
the federal National Institutes of Health (NIH) 
 
 
Genetic Information Nondiscrimination Act (GINA) 
 
A Federal law, called the Genetic Information Nondiscrimination Act (GINA), generally 
makes it illegal for health insurance companies, group health plans, and most 
employers to discriminate against you based on your genetic information. This law 
generally will protect you in the following ways:  
Health insurance companies may not request your genetic information that we get from 
this research  
Health insurance companies may not use your genetic information when deciding 
whether to insure you or the amount of money they will charge you.  
Employers may not use your genetic information that we get from this research when 
deciding to hire, promote, or fire you.  
This Federal law does not protect you against genetic discrimination by companies that 
sell life insurance, disability insurance, or long-term care insurance. 
 
What happens if I get hurt or sick because of taking part in this research study? 
 
Children's National Medical Center cannot promise that the risks we have told you about 
or other unknown problems will not happen.  If you think that you are hurt, sick, or 
otherwise harmed because of something to do with the study, please call the Principal 
Investigator, Dr. Nicholas Ah Mew, at (202)476-5863.  


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In case of a medical emergency, call 911 or go directly to the hospital. Be sure to tell the 
Emergency Room personnel and your doctor that you are on this study. 
If you have any non-emergency side effects or bad reactions, call the Principal 
Investigator, Dr. Nicholas Ah Mew, at (202)476-5863 right away. 
 
We will give you any urgent medical care needed because of your participation in this 
research study if reported in a timely manner.  Children's National will seek payment from 
your health insurance company or other third-party payor for any medical care or services 
you receive.  Children's National has no program to provide you with any additional 
payments for any injuries. 
 
  
HEALTH INSURANCE PORTABILITY AND ACCOUNTABILITY 
 
In 1996 the government passed a law known as The Health Insurance Portability and 
Accountability Act (HIPAA).  This privacy law protects your individually identifiable 
health information (Protected Health Information or PHI).  The privacy law requires you 
to sign an agreement so researchers can use or share your PHI for research purposes.  
This describes to you how information about you may be used or shared if you are in a 
research study.  It is important that you read this carefully and ask a member of the 
research team to explain anything you do not understand.  
 
I authorize the Principal Investigator, Dr. Nicholas Ah Mew, and his research staff to 
create, access, use, and disclose my PHI for the purposes described below. 
 
Protected Health Information that may be used and shared includes:  
 
Information that identifies you such as name, address, telephone number, date of birth, 
Social Security number, and other details about you 
Information that relates to your health or medical condition from your medical records 
Information obtained from the study procedures outlined in this consent form, for example: 
things done to see if you can join the study such as physical exams, blood and urine tests, 
x-rays and other tests, and any other medical information we learn from you about your 
health history and family history 
Laboratory results obtained on specimens collected from you (blood, urine, tissue) 
Questionnaires or surveys you complete 
Interviews conducted with you by members of the research team 
Audio/ video recordings 
 
The Researchers may use and share my Protected Health Information with:  
 
The Principal Investigator, other Investigators, Study Coordinators, and all administrative 
staff in charge of doing work for the study; 


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Government agencies that have the right to see or review your PHI including, but not 
limited to, the Office of Human Research Protections and the Food and Drug 
Administration; 
Children's National Medical Center Institutional Review Board; 
Audit Committee of the Children's National Medical Center Institutional Review Board;  
Quality Improvement Program Coordinator and other staff in the Office for the Protection of 
Human Subjects at Children's National Medical Center. 
 
In addition to the above people and organizations, the Researchers may also use and 
share my Protected Health Information with:   
 
Laboratories and other people or organizations that look at your health information in 
connection with this study. The name of the laboratory being used in this study is 
Children’s Hospital of Philadelphia 
The Data Safety Monitoring Board (a group of people who examine the medical 
information during the study) 
The Patient Advocate or Research Ombudsman (person who watches out for your best 
interest) 
 
Also, your primary physician will be contacted if during the course of the study the 
researcher learns of a medical condition that needs immediate attention. 
 
Should your health information be disclosed to anyone outside of the study, your 
information may no longer be protected by HIPAA and this Authorization.  However, the 
use of your health information will still be regulated by applicable federal and state laws.  
 
Storage of PHI in a Database: 
 
We would like to store personal health information collected from you in this study in a      
database for future research. The database is maintained by the Division for Genetics and 
Metabolism at Children’s National. 
 
Please indicate your approval of any or all of the following by initialing next to the 
statement: 
 
My personal health information may be stored in the above named database for                
future analysis related to this study.  
 Yes         
 No Initials __________ 
 
My personal health information may be stored in the above named database for                
future analysis related to [insert name of specific study].  
 Yes         
 No  Initials __________ 
 
My personal health information may be stored in the above named database.                    
Researchers may contact me to request my authorization for future studies that                 
are not related to this study or the disease named above.   


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 Yes      
 No Initials __________ 
 
My personal health information may be stored without any of my identifying information for 
use in other studies of other diseases.    
 Yes   
 No Initials __________ 
 
If you agree to participate in this research study, the research team, the research sponsor 
(when applicable) and the sponsor's representatives may use Personally Unidentified 
Study Data. The Personally Unidentified Study Data does not include your name, address, 
telephone, or social security number. Instead, the researcher assigns a code to the 
Personally Unidentified Study Data. Personally Unidentified Study Data may include your 
date of birth, initials, and dates you received medical care. Personally Unidentified Study 
Data may also include the health information used, created, or collected in the research 
study. The research team or the research sponsor may share the Personally Unidentified 
Study Data with others to perform additional research, place it into research databases, 
share it with researchers in the U.S. or other countries, or use it to improve the design of 
future studies. They may also publish it in scientific journals, or share it with business 
partners of the sponsor and to file applications with U.S. or foreign government agencies 
to get approval for new drugs or health care products. 
 
You do not have to sign this Consent/Authorization.  If you decide not to sign the 
Authorization, you will not be allowed to participate in the research study.  
 
After signing the Consent/Authorization, you can change your mind and revoke this 
Authorization. 
 
If you revoke the Authorization, you will send a written letter to the Principal Investigator to 
inform him of your decision. 
Dr. Nicholas Ah Mew 
Children’s National Medical Center 
Division of Genetics and Metabolism  
111 Michigan Avenue, N.W.  
Washington, DC 20010-2970 
If you revoke this Authorization, researchers may only use and disclose the PHI that was 
collected for this research study before you revoked the Authorization. 
If you revoke this Authorization, your PHI may still be used and disclosed if you should 
have an adverse event (unexpected side effect). 
If you change your mind and withdraw the Authorization, you will not be allowed to 
participate in the study. 
 
You will be allowed to review the information collected for this research study. 
 
This Authorization does not expire.  
 
If you have not already received a Notice of Privacy Practices from Children's National 
Medical Center, you may request a copy and will be given one. If you have any questions 


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or concerns about your privacy rights, you may contact the Children's Hospital Privacy 
Officer at 301-572-6348. 
 
Whom can I call if I have questions about this research study? 
 
We want you to ask questions about any part of this research study at anytime,  
 
For questions about the study or the information in this informed consent/parental 
permission document, call the Principal Investigator, Dr. Nicholas Ah Mew, at 202-476-
5863. 
 
Whom can I call if I have questions or concerns about my rights as a research study 
participant? 
 
The Children’s National Office for the Protection of Human Subjects is available to talk 
with you about:  
Your rights as a research participant 
Your concerns about the research 
A complaint about the research 
 
This is the administration office for the Institutional Review Board, which is a group of 
doctors, nurses, and non-medical people who review research studies for safety and the 
protection of people who participate in research.  You can call the Office for the 
Protection of Human Subjects at 301-565-8452. 
 
Children’s National has a bilingual (English/Spanish) research participant and family 
advocate. The advocate, Dr. Tomas Silber, is here to answer your questions or concerns 
about taking part in this research.  Dr. Silber does not work for the doctors who are doing 
this research and they do not pay him.  He is here only to help and protect you during any 
research. 
 
You may contact Dr. Silber at any time.  This can be done before you decide to take part 
in the research, during the study, or even after you finish the study.  You can call Dr. 
Silber at 202-476-3066 or reach him by e-mail at tsilber@childrensnational.org.  
 
Questions, concerns, or complaints 
 
If you have any questions, concerns or complaints about this study, call Dr. Nicholas Ah 
Mew at (202)476-5863. 
 
If you have questions about your rights, general questions, complaints, or issues as a 
person taking part in this study, call the Children’s National Medical Center Institutional 
Review Board at (202)476-3472. 
 
CONSENT 
 


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I am the study participant or I am authorized to act on behalf of the participant.  
I have read this consent form or had it read to me. 
I have been invited to take part in a research study.  I was told why the research is being 
done and how long my participation in the study is expected to last.  I was told about 
what will happen in the study and if there are any procedures or drugs that are 
experimental. 
I was told that taking part in this research is voluntary. I also was told that I can decide 
not to take part or stop being in it at any time without any penalty to me or any change 
to the quality of care I receive at Children’s National.   
I was told about the risks and possible discomforts of taking part in this research study.  
I was also informed if there are any possible benefits to me if I am in this study. 
I have been given the chance to ask questions about the study, and my questions have 
been answered.  If I have questions later, I can ask one of the people listed in this form. 
I agree to take part in this research study. 
I will receive a copy of this Informed Consent/Parental Permission form to keep. 
 
 
Signature of adult participant (18 years of age and older) 
 
Printed Name of Participant:  
 
 
 
 
 
 
 
 
 
 
Signature of Participant:  
 
 
 
 
 
 
 
 
 
 
 
 
Date and Time: 
 a.m. / p.m. (circle one) 
 
 
Signature of language interpreter (if applicable) 
 
Printed Name of Interpreter: 
 
Interpreter’s Signature:   
 
Language:  
Date and Time: 
a.m. / p.m.(circle one) 
 
 
AFFIDAVIT OF PERSON OBTAINING CONSENT / PARENTAL PERMISSION:   
 
I certify that I have explained to the above individual(s) the nature and purpose of the 
study, potential benefits, and possible risks associated with participation in this study.   
I have answered any questions that have been raised.  
 
Printed Name of Person Obtaining Consent:  
 
Research Role:  
 
Signature:  
 


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Date and Time: 
 a.m. / p.m. (circle one) 
 
                                           
Signature of Witness (if applicable) 
Printed Name of Witness: 
 
Witness’s Signature:   
 
Date and Time: 
 a.m. / p.m. (circle one) 
10.3 Informed Consent for Urea Cycle Disorder Participants  
 
 
CHILDREN'S NATIONAL MEDICAL CENTER 
Center for Genetics 
111 Michigan Avenue, NW 
Washington, DC 20010 
(202) 476-5000 
 
Consent/Parental Permission to Participate in a Clinical Research Study and 
Authorization to Use Protected Health Information 
 
TITLE OF STUDY:  
 
 
Manipulating the Gut Microbiome 
PRINCIPAL INVESTIGATOR: 
 
Nicholas Ah Mew, MD, Genetic Medicine 
 
 
 
 
 
 
Marshall Summar, MD, Genetic Medicine 
 
Throughout this document, “You” always refers to the person (you or your child) who 
takes part in the study. 
 
Introduction 
 
We are inviting you to be part of a research study at Children’s National Medical Center 
(Children’s National).  Before you decide if you would like to participate, we want you to 
know why we are doing the study.  We also want you to know about any risks (anything 
unexpected that might happen) and what you will be expected to do in the study.  
 
This form gives you information about the study.  Your study doctor or a member of the 
research team will talk to you about the study and answer all of your questions.  We 
encourage you to discuss this study with your family and anyone else you trust before 
making your decision.  You must sign this form if you agree to take part in the study.  We 
will give you a signed copy of this form to keep.  
 
Your participation in this research is voluntary. 
  
You should only take part in this study if you want to volunteer.  You should not feel that 
there is any pressure to take part in the study to please the study doctor or the research 
staff.  You are free to participate in this research or withdraw at any time.  If you 


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withdraw, your information will remain confidential. You will not have to complete the 
study and we will follow up with you as needed.  
 
The Principal Investigator may remove you from the study if you cannot complete the 
study procedures. 
You will be told of any new findings about your disease that are discovered while you 
are doing the research study.   
 
There will be no penalty or loss of benefits to which you are otherwise entitled if you 
decide not to be in the study or withdraw from the study later.   
 
This means that: 
You do not have to join the study. 
You may change your mind and stop being in the study at any time. 
We will tell you if we make any important changes to the study or if there are any 
important new findings so that you can decide if you still want to be in the study. 
If you are an employee or a medical or graduate student in training at Children’s National, 
your decision to participate or not participate will not affect your employment or academic 
standing.    
 
Why is this research study being done? 
 
Purpose of the study 
 
You are being asked to take part in a research study. The purpose of this study is to 
evaluate the drug, Lithostat (AHA or acetohydroxamic acid). We want to see if this drug 
is safe and effective for patients with a rare disease called urea cycle disorder (UCD). 
You are being asked to participate in this study because it will help find better 
treatments for patients with UCDs. Individuals with UCD cannot remove ammonia, a 
waste product, from the blood. We hope that this drug will decrease the production of 
ammonia to help patients with UCDs. About 16 people will take part in this study. 
 
You are being asked to be in the study because you met the proper criteria for eligibility 
and ineligibility after being asked a questionnaire.  
 
Lithostat is approved by the Food and Drug Administration for kidney stones. We now 
use other medications to help treat UCDs, but think that Lithostat will also be able to 
help patients with UCDs. Lithostat is an Investigational New Drug by the Food and Drug 
Administration (experimental drug).  It has been tested in adults and children in the past 
to help with kidney stones and was successful. We want to see if using Lithostat can be 
a useful addition to current treatments for urea cycle disorders in adults and children. 
 
The study will involve up to about 16 participants at 1 site nationally. All 16 participants will 
be recruited at Children’s National. 
 


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Dr. Nicholas Ah Mew is the person responsible for this research study at Children’s 
National. He is called the Principal Investigator. 
 
The NIH is paying for this research to be done. A drug company, Mission Pharmacal, is 
providing the Lithostat free of charge. 
 
What will happen in this research study? 
 
Phone screening and consent: 
If you decide to be part of this study, we will look at your medical records and collect 
your medical history. We will ask you several questions about your health, current 
medical conditions and medications to see if you are eligible to participate in this study. 
You will be informed if you are not eligible to participate in this study based off of the 
questions asked. Females: you will be asked to take a pregnancy test to make sure that 
you are not pregnant prior to starting the study. There are no direct benefits to 
participating in this study; however, your participation could help create new therapies 
for patients with urea cycle disorders. Consent will be confirmed in person the day of or 
up to a week before the start of the study. There are two study days. The study days 
must be at least 3 days apart and will take about 4-6 hours on each day. You will not 
know which day you are receiving the drug.  
 
Study day (without drug): 
We will have you fast for 4 hours prior to your appointment. When you come in that 
morning, we will take a blood sample (one venipuncture and then the IV catheter* 
remains in place for the next 4 hours) and a urine sample. Safety labs are included at the 
start of the study. The blood test will take 5 mL/1 tsp. 
 
You will then be given a single dose of 13C-urea through a different IV which will be 
inserted into the opposite arm and removed after administration of the 13C-urea. 13C-
urea is a tracer that we can see throughout your body in your blood and urine for the tests 
that we will do. The tracer is for research purposes. There is no known risk of using this 
tracer as it exists in nature and in the human body. Urea is considered by the FDA to be 
generally recognized as safe (GRAS) in multiple food products.  
 
We will observe you for 4 hours after you get the tracer. During this time, the original IV 
catheter will remain in place so that we can take 6 more blood samples (each will be 5 
mL/1 tsp.). Another urine sample will be needed at the end of the 4 hours. We will also 
measure 13C urea levels in your blood and urine and 13CO2 levels in your blood. Safety 
labs are included at the end of the 4 hours. You will not be able to eat during the study, 
but can drink water and/or pedialyte if necessary. This will conclude the study day 
without the drug. 
 
Study day (with drug):  
The next appointment will have to be at least 3 days after the first one. Again, you will 
need to fast for 4 hours prior to your appointment. You will receive the experimental drug 
on this day. Safety labs will be collected prior to you receiving the Lithostat (experimental 


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drug). We will give you one dose of the experimental drug, Lithostat. Lithostat has been 
approved by the FDA and used in patients with kidney stones for over 25 years. 1 hour 
after you take the Lithostat, we will take a blood sample (one venipuncture and then the 
IV catheter* remains in place for the next 4 hours) and a urine sample. The blood test will 
take 5 mL/1 tsp.. 
 
You will then be given a single dose of 13C-urea through a different IV which will be 
inserted into the opposite arm and removed after administration of the 13C-urea. We will 
observe you for 4 hours after you get the tracer. During this time, the original IV catheter 
will remain in place so that we can take 6 more blood samples (each will be 5 mL/1 tsp.). 
Another urine sample will be needed at the end of the 4 hours. We will alsomeasure13C 
urea levels in your blood and urine and 13CO2 levels in your blood. Safety labs are 
included at the end of the 4 hours. You will not be able to eat during the study, but can 
drink water or pedialyte if necessary. This will conclude the study day with the drug. 
 
* An intravenous catheter for blood sampling will be inserted in the arm or hand. If there is 
not adequate vascular access, a PICC (peripherally inserted central catheter) line will be 
inserted in the arm by an interventional radiologist using conscious sedation (Versed and 
Fentanyl) and will be maintained for the duration of the study by daily heparin flushes.   
Note: A PICC line is not required.  If the site IRB determines that a PICC line should not 
be used or should not be used in certain (i.e. young) subjects those restrictions will be 
described in the site’s informed consent forms.  The site PI may also decide that neither 
an intravenous catheter nor PICC line can be used, in which case the subject would not 
participate in the study until an intravenous catheter or PICC line can be used safely. 
 
The studies will be conducted at the Clinical Research Center at Children's National 
Medical Center in Washington, DC. Below is a timeline of what was just explained 
above: 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 


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Below is a table that gives you more information about what we will be measuring in your 
blood and urine during the study: 
Time point (min)
 
Baseli
ne
0 
30 
60 
90 
120 
180 
240 
Blood [13C]-urea
X
X
X
X
X
X
X
Blood urea
X
X
X
X
X
X
X
Plasma glutamine
X
X
X
X
X
X
X
Ammonia
X
X
X
X
X
X
X
Blood 13CO2
X
X
X
X
X
X
X
Urine [13C]-urea
X
X
Urine urea
X
X
Safety labs:
Hemoglobin
X
X
White blood count
X
X
Platelets
X
X
AST
X
X
ALT
X
X
Bilirubin
X
X
Creatinine
X
X
‘Baseline’ indicates at a time 0 on days when Lithostat is not administered or at a time 
prior to Lithostat administration on the days where it is administered. 
 
Is it O.K. to take other medications, dietary supplements, or alternative medicines while I 
am in this research study? 
 
There are many drugs (prescription and over-the-counter) and dietary supplements 
(including what are sometimes called “complementary” or “alternative” remedies) that 
might interact with the experimental study drug(s). Tell the study doctor about all of the 
medications and supplements you are currently taking. The study doctor will review all of 
these with you and decide if you can participate in the study. Also, you should not take 
any new medications or dietary supplements without discussing it with the study doctor 
first. 
 
How long will my participation in the research study last? 
 
You will have one appointment to determine if you are eligible to participate in the study. 
There will be two study days if you are eligible, which must be at least 3 days apart. You 
should tell us if you decide to drop out of the study. 
 
-There are any unexpected side effects 
 
-Your study doctor and/or the Sponsor of the study think it is in your best interest 
 


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What are the risks and possible discomforts from being in this research study? 
 
Lithostat (acetohydroxamic acid/AHA) 
According to the Lithostat prescribing information, adverse reactions have occurred in 
up to 30/100 of the patients receiving Lithostat. In some cases, the reactions produced 
symptoms: in others, only changes in laboratory measurements were noted. Adverse 
reactions seem to be more common in patients with pre-existing thrombophlebitis 
and/or in patients with advanced kidney problems.  
Lithostat has been an FDA approved medication for the treatment of kidney stones for 
over 25 years. According to the prescribing information, about 150 patients, including 
children, have been treated, most for periods of more than 1 year.  
 
The following reactions have been reported: 
~30/100 - Mild headaches during the first 48 hours of treatment, responsive to usual 
therapy 
Tremulousness and nervousness 
~20/100 - Gastrointestinal symptoms (nausea, vomiting, anorexia) 
~15/100 - laboratory findings characteristic of a hemolytic anemia (low iron from 
breaking down blood cells) 
Non-itchy, macular (red and bumpy) rash on the upper body and face, usually 
associated with alcoholic beverages, improved on its own 
Superficial phlebitis (inflamed vein) 
 
Acute toxicity has not occurred. Milder overdosages resulting in hemolysis (destruction 
of red blood cells) have occurred in an occasional patient with reduced kidney function 
after several weeks or months of continuous treatment. This is very unlikely to occur 
since you will only receive a single dose of the medication. 
We do not know any information about the carcinogenic (cancer causing) potential of 
Lithostat since many people haven’t studied it. Acetamide is a chemical produced when 
Lithostat is broken down. Acetamide has been shown to cause hepatocellular 
carcinoma (liver cancer) in rats at oral doses 1,500 times the human dose. Lithostat is 
cytotoxic (toxic to living cells) and can produce mutations in DNA. 
 
There is a small risk that the blood ammonia level will rise during the study. This unlikely 
possibility, would mostly likely result from toxicity of Lithostat to the liver. We will monitor 
this throughout the study. 
 
[13C]-urea is a substance regarded by the FDA to be generally regarded as safe 
(GRAS). Taking a small amount of this drug should not pose a risk to subjects with urea 
cycle disorders. The amount of ammonia generated by it would be very small compared 
to the ammonia already in the body. There is no known risk of using stable isotopes (the 
13C-urea) as they exist in nature and in the human body. Urea is considered by the FDA 
to be generally recognized as safe (GRAS) in multiple food products. 
There is a potential risk of contamination of the drug or isotope used in the study. 
However, a very careful sterile and pyrogen-free preparation of the isotope is used, and 
the drug is manufactured via Current Good Manufacturing Practices (CGMP). 


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Study Procedures:  
Venipuncture:  The vein in which the needle has been inserted to draw blood may 
become sore and red.  A temporary “black and blue mark” may develop, and rarely 
fainting may occur. The placement of the Heplock intravenous (IV) catheter for blood 
sampling could result in a bruise or infection at the site of insertion and might cause 
discomfort.  
 
If a PICC line is inserted in the arm (by an interventional radiologist) intravenous 
sedation is given and involves risks of apnea or aspiration. There is also risk of vessel 
perforation and infection of the central line catheter. 
 
There is a risk of loss of confidentiality, which could affect insurability and result in 
stigmatization. We will do our best to keep this information safe and private for your 
protection. 
 
We do not know if you will have all, some, or none of the possible risks, side effects, or 
discomforts. You should tell the study doctor, Dr. Nicholas Ah Mew, about any illness, 
side effect or discomfort that you have right away, even if it is not one of the things 
listed, or even if you think it is not related to the study. 
We will look for side effects when we examine you. The study doctor may have to lower 
the amount or stop giving the drugs if the side effects are serious. 
There may be risks we don’t know about. 
 
For female participants: Are there additional risks if I get pregnant or breastfeed my baby?  
 
The Lithostat used in this research study may have an effect on an unborn baby. You 
should not become pregnant or breast feed your baby while you are participating on this 
study.  If you are sexually active and are at risk of getting pregnant, you and your male 
partner(s) must use an effective method to avoid pregnancy or you must not have sex.   
 
The study doctor will talk to you about acceptable methods to avoid pregnancy while 
you are taking part in this study.  You will have to use the chosen method to avoid 
pregnancy or abstain (not have sexual intercourse) during your participation.  
 
Natural family planning methods (such as the rhythm method) will not be a permissible 
means of avoiding pregnancy during study participation.  If you have questions about 
this or want to change your method to avoid pregnancy, please ask the study doctor.  If 
you become pregnant during the research study, please tell the study doctor 
immediately. 
 
If you are breastfeeding a baby, the drugs used in this research could pass into the 
breast milk. You should not breastfeed your baby while you are participating in this 
study. You may need to continue to avoid breastfeeding even after your participation in 
the study is over.  Talk to the study doctor about the length of time you need to avoid 
breastfeeding. 


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For male participants: Are there additional risks if I father a baby?  
 
The Lithostat used in this research study can damage sperm. You should not father a 
child while you are participating on this study because the Lithostat may indirectly affect 
an unborn child.  If you are sexually active and are at risk of causing a pregnancy, you 
and your female partner(s) must use an effective method to avoid pregnancy or you 
must not have sex.  The study doctor will talk to you about acceptable methods to avoid 
pregnancy while you are taking part in this study. You will have to use the chosen 
method to avoid pregnancy or abstain (not have sexual intercourse) during your 
participation.  
 
Natural family planning methods (such as the rhythm method) will not be a permissible 
means of avoiding pregnancy while you are taking part in this study. If you have 
questions about this or want to change your method to avoid pregnancy, please ask the 
study doctor.  If your partner becomes pregnant during the research study, please tell 
the study doctor immediately. 
 
What are the possible benefits from being in this research study? 
 
You will not benefit directly from participating in this research study. The things we learn 
from you taking part might help other people with urea cycle disorders (including you) in 
the future by providing them with more treatment options. 
 
Alternatives: What other choices do I have if I don’t want to take part in the study? 
 
If you do not want to participate in the study, there are no other choices except not to 
take part. 
 
Will it cost me anything to take part in the study? 
 
There are no costs to you or your insurance company to participate in this study. 
Children’s National Medical Center will give you the medicine used in this study at no 
cost to you. You will not be charged for anything else we do that is part of the study. 
 
Compensation: Will I be paid for taking part in this study? 
 
You may receive up to a total of $500 after finishing this research study. The payment 
will be made in installments: [$250 for visit one, $250 for visit two]. You will be given a 
voucher to exchange for cash at the Children’s National cashier office each time you 
complete these visits.  We will also pay for your transportation to and parking at 
Children’s National when you are here to take part in the study. 
 
The Internal Revenue Service requires that any monetary payments totaling $600 or 
more in a calendar year must be reported for tax purposes. 
 


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ClinicalTrials.gov 
 
A description of this clinical trial will be available on http://www.ClinicalTrials.gov, as 
required by U.S. law.  This Web site will not include information that can identify you.  At 
most, the Web site will include a summary of the results.  You can search this Web site at 
any time. 
 
How will you protect my privacy if I take part in this study? 
Who will see the information that I give you? 
 
We will keep your study records confidential.  However, certain people may need to see 
your study records.  By law, anyone who looks at your records must keep them 
completely confidential.   
If you decide to take part in this study, only the people working on the study will know 
your name.  They will keep this information [e.g., so that we can contact you to schedule 
future appointments; in case we have to find you later to let you know of any new 
information that may affect your health].  Your personal information will not be given to 
anyone unless we get your permission in writing or if the law requires it.  This 
information will also only be given for regular hospital care, payment, and hospital 
management activities.  We will make every effort to keep your information private, but 
no one’s privacy can be totally guaranteed. 
Your medical record is confidential but, just like any medical record, there are some 
exceptions under state and federal law. 
There are some government agencies or other groups that may check records that 
identify you without your permission. They might review the records of this study and 
your medical records to make sure we are following the law and protecting the 
participants in the study.  The agencies or groups who might see these records are:  the 
research team, the Office for Human Research Protections, Department of Health and 
Human Services (DHHS), Food and Drug Administration, the sponsor (NIH Rare 
Diseases Clinical Research Network, Mission Pharmacal), Data Management and 
Coordinating Center (Tampa, FL), National Institute of Child Health and Human 
Development (NICHD) Data Safety and Monitoring Board (DSMB), and the Institutional 
Review Board of Children's National Medical Center (the ethics board and their staff that 
reviewed and approved this research study). 
The results of this research may be presented at meetings or in publications. You will not 
be personally identified. 
 
Transfer of Data to DMCC and Federal data repository 
 
The clinical information collected for this study will be stored in a computer database at 
the Data Management and Coordinating Center at the University of South Florida in 
Tampa, FL and also sent to a Federal data repository. A data repository provides a way 
for researchers to store the information collected during the research study for future 
research studies. The data management center uses several layers of protection for the 
clinical data stored in its computer database. It meets all of the local and federal security 
requirements for research datacenters. Your information is stored only using a study ID. 


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Certificate of Confidentiality  
 
Sometimes people tell us some very personal information about themselves when they 
participate in a study and it becomes part of their research record.  To help us protect your 
privacy, the investigators have obtained a Certificate of Confidentiality from the U.S. 
Department of Health and Human Services (DHHS).  
With this Certificate, the investigators cannot be forced (for example, by a court order or 
subpoena) to give information that may identify you in any federal, state or local civil or 
criminal court, or in any administrative, legislative, or other proceedings.  At sometime, 
however, DHHS might request this information as part of a review of the study records and 
medical records to make sure we are following the law and protecting the people in the 
study, and to make sure our results are correct.  If this happens, we are required to give 
DHHS all of the information they request for their review.  
 
It is important that you know that a Certificate of Confidentiality does not stop you or a 
member of your family from voluntarily giving information to others about yourself or your 
taking part in this research.  You should also know that if an insurer or employer learns 
about your participation and you give them permission to receive research information 
about you, we cannot use the Certificate of Confidentiality to keep your information private 
from them.  This means that you must also actively protect your own privacy.  
 
Finally, it is important that you know that we are not prevented from taking steps to 
prevent serious harm to you or to others.  For example, if you or anyone else might be in 
danger, we will have to report this to the authorities and get emergency help if it is 
needed.    
 
 
The Certificate cannot be used to resist a demand for information from personnel of the 
United States Government that is used for auditing or evaluation of Federally funded 
projects or for information that must be disclosed in order to meet the requirements of 
the federal National Institutes of Health (NIH) 
 
  
 
Genetic Information Nondiscrimination Act (GINA) 
 
A Federal law, called the Genetic Information Nondiscrimination Act (GINA), generally 
makes it illegal for health insurance companies, group health plans, and most 
employers to discriminate against you based on your genetic information. This law 
generally will protect you in the following ways:  
Health insurance companies may not request your genetic information that we get from 
this research  
Health insurance companies may not use your genetic information when deciding 
whether to insure you or the amount of money they will charge you.  


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Employers may not use your genetic information that we get from this research when 
deciding to hire, promote, or fire you.  
This Federal law does not protect you against genetic discrimination by companies that 
sell life insurance, disability insurance, or long-term care insurance. 
 
What happens if I get hurt or sick because of taking part in this research study? 
 
Children's National Medical Center cannot promise that the risks we have told you about 
or other unknown problems will not happen.  If you think that you are hurt, sick, or 
otherwise harmed because of something to do with the study, please call the Principal 
Investigator, Dr. Nicholas Ah Mew, at (202)476-5863.  
 
In case of a medical emergency, call 911 or go directly to the hospital. Be sure to tell the 
Emergency Room personnel and your doctor that you are on this study. 
If you have any non-emergency side effects or bad reactions, call the Principal 
Investigator, Dr. Nicholas Ah Mew, at (202)476-5863 right away. 
 
We will give you any urgent medical care needed because of your participation in this 
research study if reported in a timely manner.  Children's National will seek payment from 
your health insurance company or other third-party payor for any medical care or services 
you receive.  Children's National has no program to provide you with any additional 
payments for any injuries. 
 
  
HEALTH INSURANCE PORTABILITY AND ACCOUNTABILITY 
 
In 1996 the government passed a law known as The Health Insurance Portability and 
Accountability Act (HIPAA).  This privacy law protects your individually identifiable 
health information (Protected Health Information or PHI).  The privacy law requires you 
to sign an agreement so researchers can use or share your PHI for research purposes.  
This describes to you how information about you may be used or shared if you are in a 
research study.  It is important that you read this carefully and ask a member of the 
research team to explain anything you do not understand.  
 
I authorize the Principal Investigator, Dr. Nicholas Ah Mew, and his research staff to 
create, access, use, and disclose my PHI for the purposes described below. 
 
Protected Health Information that may be used and shared includes:  
 
Information that identifies you such as name, address, telephone number, date of birth, 
Social Security number, and other details about you 
Information that relates to your health or medical condition from your medical records 
Information obtained from the study procedures outlined in this consent form, for example: 
things done to see if you can join the study such as physical exams, blood and urine tests, 
x-rays and other tests, and any other medical information we learn from you about your 
health history and family history 


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Laboratory results obtained on specimens collected from you (blood, urine, tissue) 
Questionnaires or surveys you complete 
Interviews conducted with you by members of the research team 
Audio/ video recordings 
 
The Researchers may use and share my Protected Health Information with:  
 
The Principal Investigator, other Investigators, Study Coordinators, and all administrative 
staff in charge of doing work for the study; 
Government agencies that have the right to see or review your PHI including, but not 
limited to, the Office of Human Research Protections and the Food and Drug 
Administration; 
Children's National Medical Center Institutional Review Board; 
Audit Committee of the Children's National Medical Center Institutional Review Board;  
Quality Improvement Program Coordinator and other staff in the Office for the Protection of 
Human Subjects at Children's National Medical Center. 
 
In addition to the above people and organizations, the Researchers may also use and 
share my Protected Health Information with:   
 
Laboratories and other people or organizations that look at your health information in 
connection with this study. The name of the laboratory being used in this study is 
Children’s Hospital of Philadelphia 
The Data Safety Monitoring Board (a group of people who examine the medical 
information during the study) 
The Patient Advocate or Research Ombudsman (person who watches out for your best 
interest) 
 
Also, your primary physician will be contacted if during the course of the study the 
researcher learns of a medical condition that needs immediate attention. 
 
Should your health information be disclosed to anyone outside of the study, your 
information may no longer be protected by HIPAA and this Authorization.  However, the 
use of your health information will still be regulated by applicable federal and state laws.  
 
Storage of PHI in a Database: 
 
We would like to store personal health information collected from you in this study in a      
database for future research. The database is maintained by the Division for Genetics and 
Metabolism at Children’s National. 
 
Please indicate your approval of any or all of the following by initialing next to the 
statement: 
 
My personal health information may be stored in the above named database for                
future analysis related to this study.  


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 Yes         
 No Initials __________ 
 
My personal health information may be stored in the above named database for                
future analysis related to [insert name of specific study].  
 Yes         
 No  Initials __________ 
 
My personal health information may be stored in the above named database.                    
Researchers may contact me to request my authorization for future studies that                 
are not related to this study or the disease named above.   
 Yes      
 No Initials __________ 
 
My personal health information may be stored without any of my identifying information for 
use in other studies of other diseases.    
 Yes   
 No Initials __________ 
 
If you agree to participate in this research study, the research team, the research sponsor 
(when applicable) and the sponsor's representatives may use Personally Unidentified 
Study Data. The Personally Unidentified Study Data does not include your name, address, 
telephone, or social security number. Instead, the researcher assigns a code to the 
Personally Unidentified Study Data. Personally Unidentified Study Data may include your 
date of birth, initials, and dates you received medical care. Personally Unidentified Study 
Data may also include the health information used, created, or collected in the research 
study. The research team or the research sponsor may share the Personally Unidentified 
Study Data with others to perform additional research, place it into research databases, 
share it with researchers in the U.S. or other countries, or use it to improve the design of 
future studies. They may also publish it in scientific journals, or share it with business 
partners of the sponsor and to file applications with U.S. or foreign government agencies 
to get approval for new drugs or health care products. 
 
You do not have to sign this Consent/Authorization.  If you decide not to sign the 
Authorization, you will not be allowed to participate in the research study.  
 
After signing the Consent/Authorization, you can change your mind and revoke this 
Authorization. 
 
If you revoke the Authorization, you will send a written letter to the Principal Investigator to 
inform him of your decision. 
Dr. Nicholas Ah Mew 
Children’s National Medical Center 
Division of Genetics and Metabolism  
111 Michigan Avenue, N.W.  
Washington, DC 20010-2970 
If you revoke this Authorization, researchers may only use and disclose the PHI that was 
collected for this research study before you revoked the Authorization. 
If you revoke this Authorization, your PHI may still be used and disclosed if you should 
have an adverse event (unexpected side effect). 


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If you change your mind and withdraw the Authorization, you will not be allowed to 
participate in the study. 
 
You will be allowed to review the information collected for this research study. 
 
This Authorization does not expire.  
 
If you have not already received a Notice of Privacy Practices from Children's National 
Medical Center, you may request a copy and will be given one. If you have any questions 
or concerns about your privacy rights, you may contact the Children's Hospital Privacy 
Officer at 301-572-6348. 
 
Whom can I call if I have questions about this research study? 
 
We want you to ask questions about any part of this research study at anytime,  
 
For questions about the study or the information in this informed consent/parental 
permission document, call the Principal Investigator, Dr. Nicholas Ah Mew, at 202-476-
5863. 
 
Whom can I call if I have questions or concerns about my rights as a research study 
participant? 
 
The Children’s National Office for the Protection of Human Subjects is available to talk 
with you about:  
Your rights as a research participant 
Your concerns about the research 
A complaint about the research 
 
This is the administration office for the Institutional Review Board, which is a group of 
doctors, nurses, and non-medical people who review research studies for safety and the 
protection of people who participate in research.  You can call the Office for the 
Protection of Human Subjects at 301-565-8452. 
 
Children’s National has a bilingual (English/Spanish) research participant and family 
advocate. The advocate, Dr. Tomas Silber, is here to answer your questions or concerns 
about taking part in this research.  Dr. Silber does not work for the doctors who are doing 
this research and they do not pay him.  He is here only to help and protect you during any 
research. 
 
You may contact Dr. Silber at any time.  This can be done before you decide to take part 
in the research, during the study, or even after you finish the study.  You can call Dr. 
Silber at 202-476-3066 or reach him by e-mail at tsilber@childrensnational.org.  
 
Questions, concerns, or complaints 
 


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If you have any questions, concerns or complaints about this study, call Dr. Nicholas Ah 
Mew at (202)476-5863. 
 
If you have questions about your rights, general questions, complaints, or issues as a 
person taking part in this study, call the Children’s National Medical Center Institutional 
Review Board at (202)476-3472. 
 
CONSENT/PARENTAL PERMISSION: 
 
I am the study participant or I am authorized to act on behalf of the participant.  
I have read this consent form or had it read to me. 
I have been invited to take part in a research study.  I was told why the research is being 
done and how long my participation in the study is expected to last.  I was told about 
what will happen in the study and if there are any procedures or drugs that are 
experimental. 
I was told that taking part in this research is voluntary. I also was told that I can decide 
not to take part or stop being in it at any time without any penalty to me or any change 
to the quality of care I receive at Children’s National.   
I was told about the risks and possible discomforts of taking part in this research study.  
I was also informed if there are any possible benefits to me if I am in this study. 
I have been given the chance to ask questions about the study, and my questions have 
been answered.  If I have questions later, I can ask one of the people listed in this form. 
I agree to take part in this research study. 
I will receive a copy of this Informed Consent/Parental Permission form to keep. 
 
Signature of adult participant (18 years of age and older) 
 
Printed Name of Participant:  
 
 
 
 
 
 
 
 
 
 
Signature of Participant:  
 
 
 
 
 
 
 
 
 
 
 
 
Date and Time: 
 a.m. / p.m. (circle one) 
 
 
Signature of language interpreter (if applicable) 
 
Printed Name of Interpreter: 
 
Interpreter’s Signature:   
 
Language:  
Date and Time: 
a.m. / p.m.(circle one) 
 
 
AFFIDAVIT OF PERSON OBTAINING CONSENT / PARENTAL PERMISSION:   
 
I certify that I have explained to the above individual(s) the nature and purpose of the 
study, potential benefits, and possible risks associated with participation in this study.   


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I have answered any questions that have been raised.  
 
Printed Name of Person Obtaining Consent:  
 
Research Role:  
 
Signature:  
 
Date and Time: 
 a.m. / p.m. (circle one)