Clinical trial NCT03168295
Conditions: Diabetes Mellitus, Type 2
Sponsor: The University of Texas Health Science Center at San Antonio
Start date: 2016-10-01; Completion date: 2019-05-15
Enrollment: 34 participants; Allocation: RANDOMIZED; Intervention model: CROSSOVER

Brief summary:
Purpose/Objectives: Examining the effect of SGLT2 inhibition on EGP and plasma glucose concentration in diabetic and non-diabetic subjects after kidney transplantation (i.e. renal denervation) or in subjects after renal sympathectomy (63) can add insight about the possible role of a neural arc which mediates the changes in plasma glucagon and/or insulin concentration in response to glucosuria.

Detailed description:
Purpose/Objectives: Examining the effect of SGLT2 inhibition on EGP and plasma glucose concentration in diabetic and non-diabetic subjects after kidney transplantation (i.e. renal denervation) or in subjects after renal sympathectomy (63) can add insight about the possible role of a neural arc which mediates the changes in plasma glucagon and/or insulin concentration in response to glucosuria.

Research Design/Plan: After screening, eligible subjects will receive 2 measurements of endogenous glucose production with a prime-continuous infusion of 3-3H-glucose. Each measurement will be performed on a separate day in random order after a 10-12 hour overnight fast and will last 8 hours (from 6 AM to 2 PM). After a 3-hour tracer equilibration period, each subject will receive one of the following medications in random order: (i) placebo and (ii) dapagliflozin 10 mg. Following the test medication at 9 AM, blood samples will be drawn every 20 minutes for an additional 5 hours and plasma glucose, insulin, C-peptide, glucagon, catecholamine concentrations and tritiated glucose sp act will be measured.

Methods: Visit 1: Screening Visit 2: Endogenous Glucose Production Measurement (EGP) Visit 3: After completing the first EGP measurement, subjects will return to the Diabetes Research Unit for the second study.

Arms: arm 1: Renal transplant subjects with intact native kidneys with Type 2 Diabetes Mellitus receive dapagliflozin then placebo arm 2: Renal transplant subjects with intact native kidneys who are non-diabetic receive placebo then dapagliflozin arm 3: Subjects who are type 2 diabetes mellitus who have not undergone renal transplant.
Interventions: intervention 1: Dapagliflozin 10mg then Placebo Oral Tablet intervention 2: Placebo Oral Tablet then Dapagliflozin 10mg
Intervention descriptions: intervention 1: SGLT2 inhibitor - Dapagliflozin then Placebo intervention 2: Placebo then SGLT2 inhibitor - Dapagliflozin

Protocol documents:
Prot_SAP_000.pdf: 
 
16-042H, DeFronzo, Form BC, RS, 01-05-17, AMD 
vSept3-2014 
1 
 
 
 
COVER PAGE FOR PROTOCOL AND STATISTICAL ALNALYSIS 
 
Official Study Title: SGLT2 INHIBITION AND STIMULATION OF ENDOGENOUS                       
GLUCOSE PRODUCTION Significance - Protocol 3: Role of the Renal Nerves in the 
Increase in EGP in Response to Glucosuria 
 
NCT number: NCT03168295 
 
IRB Approval Date: 01/05/2017 
 
Unique Protocol ID: HSC20160042 
 
 


 
16-042H, DeFronzo, Form BC, RS, 01-05-17, AMD 
vSept3-2014 
2 
Protocol Template Form 
 
Item 1 UTHSCSA 
Tracking Number 
HSC20160042 
 
Item 2 Abstract / Project Summary 
Provide a succinct and accurate description of the proposed 
research. State the purpose/aims. Describe concisely the research 
design and methods for achieving the stated goals. This section 
should be understandable to all members of the IRB, scientific and 
non-scientific.   
DO NOT EXCEED THE SPACE PROVIDED. 
Purpose/Objectives: Examining the effect of SGLT2 inhibition on EGP and plasma glucose concentration in diabetic subjects after 
kidney transplantation (i.e. renal denervation) or in subjects after renal sympathectomy (63) can add insight about the possible role of 
a neural arc which mediates the changes in plasma glucagon and/or insulin concentration in response to glucosuria. 
 
Research Design/Plan: After screening, eligible subjects will receive 2 measurements of endogenous glucose production with a 
prime-continuous infusion of 3-3H-glucose. Each measurement will be performed on a separate day in random order after a 10-12 
hour overnight fast and will last 8 hours (from 6 AM to 2 PM). After a 3-hour tracer equilibration period, each subject will receive 
one of the following medications in random order: (i) placebo and (ii) dapagliflozin 10 mg.  Following the test medication at 9 AM, 
blood samples will be drawn every 20 minutes for an additional 5 hours and plasma glucose, insulin, C-peptide, glucagon, 
catecholamine concentrations and tritiated glucose sp act will be measured. 
 
Methods: Visit 1: Screening  
Visit 2: Endogenous Glucose Production Measurement (EGP) 
Visit 3: After completing the first EGP measurement, subjects will return to the Diabetes Research Unit for the second study.  
 
 
Item 3 
Background 
 
Describe past experimental 
and/or clinical findings 
leading to the formulation 
of your study.   
For research involving 
unapproved drugs, 
describe animal and 
human studies.   
For research that involves 
approved drugs or devices, 
describe the FDA approved 
uses of this drug/device in 
relation to your protocol. 
The rise in EGP following SGLT2 inhibition is associated with an increase in plasma glucagon 
concentration and progressive decline in plasma insulin concentration (10,11). Although SGLT2 
transporters have been demonstrated on alpha cells (55), there are no SGLT2 transporters on beta 
cells (55).  Moreover, the rise in plasma glucagon does not precede, but occurs simultaneously with or 
slightly after the rise in EGP.  These observations suggest that glucosuria initiates a neural arc in which 
activation of the renal sympathetic nerves sends a signal to the brain which in turn leads to:  (i) 
inhibition of insulin secretion; (ii) stimulation of glucagon secretion; (iii) inhibition of hepatic glucose 
production; or (iv) some combination of the three.   
Item 4 
Purpose and rationale 
Insert purpose, objectives 
and research 
questions/hypotheses 
here. 
 If you cut and paste from 
another document, make 
sure the excerpted 
material answers the 
question 
Insert purpose: Examining the effect of SGLT2 inhibition on EGP and plasma glucose concentration in 
diabetic subjects after kidney transplantation (i.e. renal denervation) or in subjects after renal 
sympathectomy (63) can add insight about the possible role of a neural arc which mediates the 
changes in plasma glucagon and/or insulin concentration in response to glucosuria. 


 
16-042H, DeFronzo, Form BC, RS, 01-05-17, AMD 
vSept3-2014 
3 
 
 
Item 5 
Study Population(s) Being 
Recruited 
 
In your recruitment plan, how 
many different populations of 
prospective subjects do you plan to 
target? Provide number:        
 
 
 
Identify the criteria for inclusion: 
 
 
Identify the criteria for exclusion: 
e.g., a population can be individuals 
with type 2 diabetes controlled with 
diet and/or a population of healthy 
controls.  Or a population can be 
individuals attending an education 
program, etc. 
 
List each different population on a 
separate row and provide a short 
descriptive label:   
(e.g., normal-healthy, diabetics, 
parents, children, etc.) 
 
To add rows use copy & paste 
20 post-renal transplant T2DM 
subjects 
• 
age = 18-70 years 
• 
BMI = 18.5-40 kg/m2 
• 
HbA1c  ≥ 7.0% and ≤10.0%. 
• 
males or females 
• 
Must be at least 3 months post 
renal transplantation and be on a 
stable dose of prednisone (≤5 
mg/day), tacrolimus, and 
mycophenolate mofetil   
• 
Not taking any antidiabetic 
medications or who are treated 
with metformin, sulfonylurea, 
DPP4 inhibitor, thiazolidinedione or 
some combination  
• 
Must be in good general health as 
determined by physical exam, 
medical history, blood chemistries, 
CBC, TSH, T4, EKG and urinanalysis 
 
• 
Subjects who are taking insulin or 
SGLT2 inhibitor are excluded 
• 
Only subjects whose body weight 
has not been stable (± 3 lbs) over 
the preceding three months and/or 
who participate in an excessively 
heavy exercise program will be 
excluded. 
• 
Individuals with evidence of 
proliferative diabetic retinopathy, 
plasma creatinine >1.4 females or 
>1.5 males (and eGFR 
<45ml/min.1.73m2), or 24-hour 
urine albumin excretion > 300 mg 
will be excluded.   
20 T2DM subjects without renal 
transplant (CONTROL) 
• 
age = 18-70 years 
• 
BMI = 18.5-40 kg/m2 
• 
 HbA1c  ≥ 7.0% and≤ 10.0%. 
• 
males or females 
• 
On stable dose (more than 3 
months) of monotherapy or 
combination therapy with 
metformin and/or a sulfonylurea  
• 
Must be in good general health as 
determined by physical exam, 
medical history, blood chemistries, 
CBC, TSH, T4, EKG and urinanalysis 
• 
Subjects taking drugs known to 
affect glucose metabolism (other 
than metformin and sulfonylurea)  
• 
Only subjects whose body weight 
has not been stable (± 3 lbs) over 
the preceding three months and/or 
who participate in an excessively 
heavy exercise program will be 
excluded. 
• 
Individuals with evidence of 
proliferative diabetic retinopathy, 
plasma creatinine >1.4 females or 


 
16-042H, DeFronzo, Form BC, RS, 01-05-17, AMD 
vSept3-2014 
4 
• 
 
>1.5 males (and eGFR <45 
ml/min.1.73m2), or 24-hour urine 
albumin excretion > 300 mg will be 
excluded.   
 
 
Item 6 
Research Plan / Description of the Research Methods a.  Provide a comprehensive narrative describing the research methods.   
Provide the plan for data analysis (include as applicable the sample size calculation). 
 
Step-by-Step Methods:  
Visit 1: Screening. Medical history will be obtained and physical exam performed. Blood will be drawn for FPG, routine 
blood chemistries, CBC lipid profile, HbA1c, and thyroid function. Urinanalysis, EKG, albumin/creatinine ratio and 
pregnancy test will be performed.  
Visits 2 & 3: Endogenous Glucose Production Measurement: The rate of EGP will be measured with 3-3H-glucose 
infusion. [3-3H]-glucose infusion will be started at 6 AM and continued until 2 PM (5 hours after drug administration). 
After 3 hours of tracer equilibration, baseline blood samples will be drawn and subjects will receive placebo or 
dapagliflozin and arterialized blood samples will be obtained every 10-20 minutes from 9 AM to 2 PM. Plasma glucose, 
insulin, C-peptide, glucagon, catecholamine concentrations and [3-3H]-glucose specific activity will be measured. Blood 
will also be drawn to monitor kidney function. Urine will be collected from 6 to 9 AM and from 9 AM to 2 PM. Urinary 
volume and glucose concentration will be measured and urinary glucose excretion rate calculated. The study will end at 
2 PM.  After completing the first study, subjects will return to the unit for the second study that will be performed in 
random order with a 5-14 day interval between each study. 
 
Data Analysis Plan: The primary endpoint is the difference in EGP during the last hour of EGP measurement in diabetic 
patients versus diabetic patients without renal transplantation.  In our previous study (10) the mean difference in EGP 
between diabetic subjects who received dapagliflozin versus placebo was 0.70±0.34 (mean ±SD).  If renal denervation 
(i.e., renal transplant diabetic patients) reduces the dapagliflozin-induced rise in EGP, as we hypothesize, by  50% 
compared to dapagliflozin-treated non-renal-transplant diabetic subjects, we computed that 40 subjects (20 per group) 
are required to demonstrate statistical significance with 90% power and alpha = 0.05.   
In a secondary analysis we will compare renal transplant diabetic patients treated with dapagliflozin versus placebo. If, 
as we hypothesize, the renal nerves contribute in part (50%) to the excessive rise in EGP following dapagliflozin 
(0.70±0.34), the difference in EGP between the two groups during the last hour of EGP measurement should be 
reduced by more than 50%.  To detect a difference of less than 50% dapagliflozin-treated versus placebo-treated 
diabetic renal transplant patients with 90% power and alpha=0.05, we computed that 20 subjects are required (10 
dapagliflozin and 10 placebo). 
 


 
16-042H, DeFronzo, Form BC, RS, 01-05-17, AMD 
vSept3-2014 
5 
Item 7 Risks Section: 
Complete the following table to describe the risks of all research procedures listed in Step 2, Institutional Form (items 28-34).  Do not list risks of Routine care 
procedures here.  
 ☒ N/A, Risks are described in the informed consent document – do not complete this table. 
Research procedures 
 
example: 
• 
History and physical 
• 
Questionnaire 
• 
Laboratory tests 
 
Add or delete rows as needed 
Risks 
 
List the reasonably expected risks 
under the following categories as appropriate: 
Insert procedure here 
Serious and likely; 
o Insert risk here or enter "none" 
Serious and less likely; 
o Insert risk here or enter "none" 
Serious and rare; 
o Insert risk here or enter "none" 
Not serious and likely; 
o Insert risk here or enter "none" 
Not serious and less likely 
o Insert risk here or enter "none" 
Insert procedure here 
Serious and likely; 
o Insert risk here or enter "none" 
Serious and less likely; 
o Insert risk here or enter "none" 
Serious and rare; 
o Insert risk here or enter "none" 
Not serious and likely; 
o Insert risk here or enter "none" 
Not serious and less likely 
o Insert risk here or enter "none" 
Insert procedure here 
Serious and likely; 
o Insert risk here or enter "none" 
Serious and less likely; 
o Insert risk here or enter "none" 
Serious and rare; 
o Insert risk here or enter "none" 
Not serious and likely; 
o Insert risk here or enter "none" 
Not serious and less likely 
o Insert risk here or enter "none"