A Phase 1b Dose-escalating Study With RBT-1 in Healthy Volunteers and Subjects With Stage 3/4 Chronic Kidney Disease
Phase: PHASE1
Conditions: Healthy Volunteers, Chronic Kidney Disease
Sponsor: Renibus Therapeutics, Inc.

 
 
Clinical Protocol REN-001A 
 
A Phase 1b dose-escalating study with RBT-1, in healthy 
volunteers and subjects with Stage 3-4 Chronic Kidney Disease 
IND 138109 
SPONSOR 
Renibus Therapeutics, Inc. 
950 E State Highway 114, Suite 160 
Southlake, TX 76092 
 
 
Original Protocol: 26 July 2019 
Revision 03: 15 January 2020 
 
 
 
 
 
 
 
 
CONFIDENTIALITY STATEMENT 
Part or all of the information in this protocol may be unpublished material. Accordingly, 
this protocol is to be treated as confidential and restricted to its intended use. This 
material is the property of Renibus Therapeutics, Inc. and must not be disclosed or used 
except as authorized in writing by Renibus Therapeutics, Inc. 

Protocol Number: REN-001A (Revision 3) 
Date: 15 January 2020 
CONFIDENTIAL 
 
 
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Table of Contents 
Table of Contents ...................................................................................................................................... 2 
1 
STUDY TITLE ..................................................................................................................................... 5 
2 
SPONSOR INFORMATION ................................................................................................................ 5 
2.1 
Sponsor: .................................................................................................................................... 5 
3 
LIST OF ABBREVIATIONS ............................................................................................................... 6 
5 
EVENT SCHEDULE.......................................................................................................................... 15 
5.1 
Event Schedule – Cohorts 1-7 ................................................................................................ 15 
5.2 
Event Schedule – Cohorts 8 -10 ............................................................................................. 16 
6 
INTRODUCTION .............................................................................................................................. 17 
6.1 
Background Information ........................................................................................................ 17 
6.2 
Study Drug ............................................................................................................................. 18 
6.3 
Preclinical Experience ............................................................................................................ 18 
6.4 
Clinical Experience ................................................................................................................ 18 
7 
STUDY OBJECTIVES ....................................................................................................................... 20 
7.1 
Primary Objectives ................................................................................................................. 20 
8 
INFORMED CONSENT .................................................................................................................... 20 
9 
STUDY POPULATION ..................................................................................................................... 21 
9.1 
Healthy Volunteer (HV) ......................................................................................................... 21 
9.1.2 
HV Exclusion Criteria ............................................................................................................ 21 
9.2 
CKD Subjects ......................................................................................................................... 22 
9.2.2 
CKD Exclusion Criteria ......................................................................................................... 22 
9.3 
Study Design .......................................................................................................................... 23 
9.3.1 
Stopping Rules ....................................................................................................................... 24 
9.4 
Recordkeeping and Monitoring .............................................................................................. 24 
9.5 
Investigational Supplies ......................................................................................................... 24 
9.5.1 
Study Drug Description .......................................................................................................... 24 
9.5.2 
Packaging ............................................................................................................................... 24 
9.5.3 
Investigational Product Dispensing ........................................................................................ 25 
9.5.4 
Dosage Preparation and Administration ................................................................................. 25 
9.5.5 
Storage Requirements ............................................................................................................. 25 
9.5.6 
Investigational Product Accountability .................................................................................. 25 
9.5.7 
Retrieval and Destruction ....................................................................................................... 25 
9.6 
Study Visits ............................................................................................................................ 25 
9.6.2 
Screening (Within 14 Days Prior to Check-in Day) ............................................................... 26 
9.6.3 
Study Day -1, a day prior to dosing ........................................................................................ 26 
9.6.4 
Study Day 1 ............................................................................................................................ 26 
9.6.5 
Study Day 2 ............................................................................................................................ 28 

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9.6.6 
Study Days 3,4,5,8 (Day 8  1 day) ....................................................................................... 28 
9.6.7 
Study Day 14 (Cohorts 1-7) ................................................................................................... 28 
9.6.8 
Study Day 28/End of Study Visit (28  1 days following the RBT-1 dose) .......................... 28 
9.7 
Clinical Laboratory Evaluations ............................................................................................. 29 
9.7.1 
Blood Chemistry, Hematology, Pharmacokinetic and Response biomarker Samples ........... 29 
9.7.2 
Urine Samples ........................................................................................................................ 29 
9.8 
Clinical Procedures and Observations .................................................................................... 29 
9.8.1 
ECG ........................................................................................................................................ 29 
9.8.2 
Concomitant Medications ....................................................................................................... 29 
9.8.3 
Physical Examination ............................................................................................................. 29 
9.8.4 
Vital Signs .............................................................................................................................. 30 
9.8.5 
Meals and Dose Administration ............................................................................................. 30 
9.8.6 
Prohibited Medications........................................................................................................... 30 
10 
ADVERSE EVENT REPORTING ..................................................................................................... 30 
10.1 
Investigator Reporting Requirements ..................................................................................... 30 
10.2 
Definitions .............................................................................................................................. 31 
10.3 
Breaking the Blind.................................................................................................................. 32 
11 
STATISTICAL CONSIDERATIONS ................................................................................................ 32 
11.1 
Study Populations ................................................................................................................... 32 
11.2 
Demographic and Baseline Characteristics ............................................................................ 33 
11.3 
Analysis of Efficacy Endpoints .............................................................................................. 33 
11.4 
Analysis of Pharmacodynamic/Safety Endpoints .................................................................. 33 
11.5 
Analysis of Pharmacokinetic (PK) Data ................................................................................. 34 
11.6 
Sample Size Calculations ....................................................................................................... 34 
11.7 
Interim Analysis ..................................................................................................................... 34 
12 
WITHDRAWAL FROM STUDY ...................................................................................................... 34 
13 
DATA MANAGEMENT .................................................................................................................... 35 
13.1 
Database Lock ........................................................................................................................ 35 
14 
ETHICAL CONSIDERATIONS ........................................................................................................ 35 
14.1 
Ethical Conduct of the Study .................................................................................................. 35 
14.2 
Regulatory Considerations ..................................................................................................... 36 
14.3 
Protocol Amendments and Study Termination ...................................................................... 36 
14.4 
Safety Monitoring................................................................................................................... 36 
14.5 
Quality Control and Quality Assurance ................................................................................. 36 
15 
GENERAL CONSIDERATIONS ...................................................................................................... 37 
15.1 
Discontinuation of the Study .................................................................................................. 37 
16 
AGREEMENT WITH PROTOCOL .................................................................................................. 38 
Principal Investigator:.............................................................................................................................. 38 

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Protocol REN-001A ................................................................................................................................ 38 
17 
REFERENCES ................................................................................................................................... 39 
Appendix 1Safety Clinical Chemistry, Hematology, and Urinalysis Tests Performed by the Laboratory at Screening, 
During the Study, and at Follow-up (EOS) ............................................................................................. 41 
 

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1 STUDY TITLE 
A Phase 1b dose-escalating study with RBT-1, in healthy volunteers and subjects with Stage 3-4 
Chronic Kidney Disease 
 
2 SPONSOR INFORMATION 
2.1 
Sponsor: 
 
Name: 
Renibus Therapeutics, Inc. 
Address: 
950 E State Highway 114, Suite 160 
Southlake, TX 76092 
2.2 
Sponsor Representative: 
 
Name: 
Bhupinder Singh, MD, FASN, FNKF, FCRS 
Title 
Chief Scientific Officer and Medical Monitor 
Affiliation: 
Renibus Therapeutics, Inc. 
Address: 
950 E State Highway 114, Suite 160 
Southlake, TX 76092 
Mobile: 
(480) 220-7084 
E-mail: 
medicalmonitor@renibus.com 
 
 
 
 
Bhupinder Singh, MD, FASN, FNKF, FCRS 
Date 
Chief Scientific Officer and Medical Monitor 
Renibus Therapeutics, Inc. 

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3 LIST OF ABBREVIATIONS 
 
 
Abbreviation 
Definition 
AE 
Adverse event 
AKI 
acute kidney injury 
ALT 
alanine aminotransferase 
ARB 
angiotensin-receptor blockers 
AST 
aspartate aminotransferase 
AUC(0-t) 
area under the concentration-time curve from time 0 to t 
AUC(0-inf) 
area under the concentration-time curve from time 0 to infinity 
BUN 
blood urea nitrogen 
CFR 
Code of Federal Regulations 
CIOMS 
Council for International Organizations of Medical Sciences 
CKD 
chronic kidney disease 
CL 
clearance 
Cmax 
maximum serum or plasma concentration 
Cr 
creatinine 
CRO 
contract research organization 
ECG 
electrocardiogram 
eCRF 
electronic case report form 
EDC 
electronic data capture 
FDA 
Food and Drug Administration 
FeS 
Iron sucrose 
GCP 
Good Clinical Practice 
GFR 
glomerular filtration rate 
GLP 
Good Laboratory Practice 
HO-1 
Heme oxygenase 
ICF 
informed consent form 
ICH 
International Conference on Harmonisation 
ICSR 
Individual Case Safety Report 
IEC 
Independent Ethics Committee 
IRB 
Institutional Review Board 
IV 
intravenous 
Ll-6 
Interleukin 6 
IL-10 
Interleukin 10 
IND 
investigational new drug 
IRB 
Institutional Review Board 
ITT 
Intent-to-Treat 
KDIGO 
KIM-1 
Kidney Disease: Improving Global Outcomes 
Kidney Injury Molecule-1 

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Abbreviation 
Definition 
λz 
elimination rate constant 
MedDRA 
Medical Dictionary for Regulatory Activities 
MITT 
NAG 
NGAL 
Modified Intent-to-Treat 
N acetyl-beta-D-glucosaminidase 
Neutrophil Gelatinase-Associated Lipocalin 
NOAEL 
no-observed-adverse-effect level 
PK 
Pharmacokinetic(s) 
POC 
Proof of Concept 
PP 
Per Protocol 
SnPP 
Stannous Protoporphyrin 
TEAE 
treatment emergent adverse event 
T1/2 
elimination half-life 
Tmax 
time to maximum serum concentration 
Vz 
volume of distribution 

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4 STUDY SYNOPSIS 
 
 
Renibus Therapeutics, Inc. 
Protocol No. REN-001A 
Name of Drug: RBT-1 
Phase of Development: 1b 
Name of Active Ingredient: 
Iron Sucrose (FeS) and Stannous protoporphyrin (SnPP) 
Date of Study Synopsis 
15 January 2020 
Protocol Title: 
A Phase 1b dose-escalating study with RBT-1, in healthy volunteers and subjects with Stage 3-4 
Chronic Kidney Disease 
Investigational Sites: 
One contract research organization in the US. 
Study Objectives: 
The primary objectives of the study are to evaluate: 
1. The safety and tolerability of RBT-1 in healthy volunteers and in subjects with stage 3-4 
Chronic Kidney Disease (CKD). 
2. The effect of RBT-1 on biomarkers which are potential surrogates for cytoprotective 
activity in healthy volunteers and in subjects with Stage 3-4 CKD. 
3. To establish the optimal dose that could potentially be used for testing in subjects at risk 
for developing Acute Kidney Injury (AKI). 
4. To study the Pharmacokinetics of SnPP 
Number Subjects to be Enrolled: 
Up to 60 subjects consisting of healthy volunteers and subjects with CKD will receive single 
doses of RBT-1. The initial 18 healthy volunteer subjects will be enrolled in one of three dose 
levels starting at the lowest dose of 9 mg SnPP and 240 mg of FeS. The initial 24 subjects 
with stage 3-4 CKD will be enrolled in one of two dose levels starting at the lowest dose of 
27 mg SnPP and 240 mg of FeS. After a safety and biomarker response evaluation, 6 CKD 
subjects will be dosed at 63 mg SnPP and 240 mg of FeS and an additional 6 CKD subjects 
may be dosed at 45 mg SnPP and 240 mg of FeS.  An additional cohort of 6 subjects 
consisting of healthy volunteers and CKD patients may be dosed at 90 mg SnPP and 240 mg 
of FeS. 

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Study Design: 
This is a Phase 1b, single-center, dose-escalating study to evaluate the safety, tolerability, PK and 
pharmacodynamic effect of RBT-1 in healthy volunteers and in subjects with stage 3-4 CKD. The 
following biomarkers will be used as surrogate measures of cytoprotective activity: Haptoglobin, 
Ferritin, transferrin saturation, Bilirubin, Hemopexin, IL-10, and Heme Oxygenase-1. 
Additionally, the p21 biomarker will be monitored at various points of the study as well as urine 
biomarker response to RBT-1. 
Screening data will be reviewed to determine subject eligibility. Subjects who meet all inclusion 
criteria and none of the exclusion criteria are eligible to be enrolled into the study. 
The study is designed as follows: 
• 
A screening period with baseline evaluations for study eligibility. 
• 
Baseline for various biomarkers will be established by three different measurements in 
blood and urine prior to dosing at Screening, Day –1 and on the day of dose 
administration prior to dosing. 
• 
If subjects meet eligibility criteria, they will receive a single dose of RBT-1 by slow 
intravenous injection over a 120-minutes on study day (SD) 1. 
• 
Subjects will stay in the clinic for the initial 24 hours after administration of RBT-1 and 
will be discharged on SD 2 if no safety issues appear. 
• 
The study will initially be dose-escalating in 3 groups of 6 healthy volunteers each, for a 
total of 18 healthy volunteers, evaluating escalating single dose of RBT-1 starting with a 
dose of 9 mg SnPP and 240 mg of FeS, followed by 27 mg SnPP and 240 mg of FeS, and 
90 mg SnPP with 240 mg of FeS. Dose-escalation from one dose level to the next will 
only be allowed after a careful review of the safety, tolerability and PK data from the prior 
dose group as determined by the Data and Safety Monitoring Board (DSMB). 
• 
Additional patients may be enrolled in one of three dose levels starting at the dose of 63 
mg SnPP and 240 mg of FeS for CKD patients.  After a safety and biomarker response 
evaluation, CKD patients may be dosed at 45 mg SnPP and 240 mg of FeS.  Healthy and 
CKD patients may be dosed at 90 mg SnPP and 240 mg of FeS.  
• 
Subjects will be followed for 28 1 days after the dose of RBT-1. Subjects with persistent 
treatment related adverse events at Day 28 or new onset treatment related adverse events 
after Day 28 will be followed for 60 days. If after 60 days of study drug administration, an 
investigator becomes aware of an SAE that he or she suspects is related to study drug, the 
investigator should report it to the Sponsor. 
• 
Response biomarkers will be assessed at baseline (SD 1 prior to dose administration) and 
2, 4, 8, 12, 18, 24, 48, 72, 96 and 168 hours after study drug administration. Safety will be 
assessed for up to 28 1 days after study drug administration. 
• 
Blood samples for SnPP pharmacokinetic analysis will be assessed at baseline (SD 1 prior 
to dose administration) and 1, 2, 3, 4, 6, 8, 12, 18, and 24 hours after study drug 
administration. Urine samples will be collected and centrifuged and analyzed for subject 
responsiveness to RBT-1 therapy. 
• 
Urinary Clearance of SnPP will be assessed by the measurement of urinary tin over the 24-
hour post dose period. 
• 
Total study duration will be 60 1 days for each subject, in addition to a screening period 
of up to 14 days. 
• 
 

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Endpoints: 
 
Pharmacodynamic/Safety Assessment: 
 
The safety and tolerability of RBT-1 will be assessed by determining the incidence, relationship 
to study drug, and severity of treatment-emergent adverse events (TEAEs), withdrawals due to 
adverse events (AEs), and changes in vital signs, laboratory tests, changes in concomitant 
medication use due to AEs, and other standard safety parameters 
 
Biomarker Monitoring 
The following biomarkers will be evaluated: Haptoglobin (Hp), Ferritin, Transferrin Saturation, 
Bilirubin, Hemopexin, InterLeukin-10, Heme Oxygenase 1 (HO-1) and p21, as well as urine 
biomarker response to RBT-1. Biomarkers will be measured at baseline and 2, 4, 8, 12, 18, 24, 
48, 72, 96 and 168 hours after administration of RBT-1. 

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Healthy Volunteer Subjects 
 
Inclusion Criteria: 
1. Male and female subjects age 18 to 80 years (inclusive, at time of consent). 
2. Body weight <125 kg. 
3. Able and willing to comply with all study procedures. 
4. Female subjects must be either post-menopausal for at least 1 year or surgically sterile 
(tubal ligation, hysterectomy or bilateral oophorectomy) for at least 3 months, or if of 
childbearing potential, have a negative pregnancy test and agree to use dual methods of 
contraception, or abstain from sexual activity from Screening until 281 days after study 
drug administration. 
Male subjects with female partners of childbearing potential must agree to use a highly 
effective method of contraception from screening until 281 days after study drug 
administration. All fertile men with female partners of childbearing potential should be 
instructed to contact the Investigator immediately if they suspect their partner might be 
pregnant (e.g., missed or late menstrual period) at any time during study participation. 
Exclusion Criteria: 
1. History of malignancy except carcinoma in situ in the cervix, early stage prostate cancer 
or non-melanoma skin cancers. Cancer free for less than five years. 
2. Use of investigational drugs or participation in another clinical trial within 30 days or <5 
half-lives prior to screening, whichever is longer. 
3. Serum ferritin > 500 ng/ml or who have received IV iron within 28 days of screening. 
4. Women who are pregnant, breastfeeding, or planning to become pregnant while 
participating in the study. 
5. Any significant acute or chronic diseases. 
6. Subjects with abnormal baseline liver tests or hepatitis serologies that suggest active 
infection. 
7. Regular use of drugs of abuse and/or positive findings on urinary drug screening. 
8. Current tobacco use and/or positive findings on urinary cotinine screening. 
9. Subjects who are severely physically or mentally incapacitated and who, in the opinion of 
investigator, are unable to perform the subjects’ tasks associated with the protocol. 
10. Presence of any condition which, in the opinion of the investigator, places the subject at 
undue risk or potentially jeopardizes the quality of the data to be generated. 
11. Subjects with history of photosensitivity or active skin disease, which in the opinion of 
the investigator could increase the risk of photosensitivity. 
12. Known hypersensitivity or previous anaphylaxis to FeS, SnPP or tin based products. 
 
 
 
 

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CKD Subjects 
 
Inclusion Criteria: 
1. Male and female subjects age 18 to 80 years (inclusive, at time of consent). 
2. Body weight <125 kg. 
3. Able and willing to comply with all study procedures. 
4. Female subjects must be either post-menopausal for at least 1 year or surgically sterile 
(tubal ligation, hysterectomy or bilateral oophorectomy) for at least 3 months, or if of 
childbearing potential, have a negative pregnancy test and agree to use dual methods of 
contraception, or abstain from sexual activity from Screening until 281 days after study 
drug administration. 
Male subjects with female partners of childbearing potential must agree to use a highly 
effective method of contraception from screening until 281 days after study drug 
administration. All fertile men with female partners of childbearing potential should be 
instructed to contact the Investigator immediately if they suspect their partner might be 
pregnant (e.g., missed or late menstrual period) at any time during study participation. 
5. CKD stage 3 as determined by a GFR between 30-59 ml/min as estimated using the 
CKD-EPI equation. 
6. CKD stage 4 as determined by a GFR between 15-29 ml/min as estimated using the 
CKD-EPI equation. 
Exclusion Criteria: 
1. History of malignancy except carcinoma in situ in the cervix, early stage prostate cancer 
or non-melanoma skin cancers. Cancer free for less than 5 years. 
2. Use of investigational drugs or participation in another clinical trial within 30 days or 5 
half-lives prior to screening, whichever is longer. 
3. Serum ferritin >500 ng/ml or who have received IV iron within 28 days of screening, or 
currently being treated with oral iron. 
4. Women who are pregnant, breastfeeding, or planning to become pregnant while 
participating in the study. 
5. Regular use of drugs of abuse and/or positive findings on urinary drug screening. 
6. Current tobacco use and/or positive findings on urinary cotinine screening. 
7. Subjects who are severely physically or mentally incapacitated and who, in the opinion of 
investigator, are unable to perform the subjects’ tasks associated with the protocol. 
8. Presence of any condition which, in the opinion of the investigator, places the subject at 
undue risk or potentially jeopardizes the quality of the data to be generated. 
9. Subjects with history of photosensitivity or active skin disease, which, in the opinion of 
the investigator could increase the risk of photosensitivity. 
10. Subjects with abnormal baseline liver tests or hepatitis serologies that suggest active 
infection. 
11. Subjects with CKD and not at their baseline of renal function and have significant acute 
or chronic illnesses. 
12. Known hypersensitivity or previous anaphylaxis to FeS, SnPP or to components thereof. 
 
 
 

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Drug, Dose and Mode of Administration: 
RBT-1 is supplied as a sterile liquid (in separate vials of FeS and SnPP) for intravenous (IV) 
injection and intended for single use. Glass vials are plugged with Teflon-coated rubber stoppers 
and sealed with aluminum seals. Vials of 5 mL will be used for each cohort. 
RBT-1 at a dose of either 9 mg SnPP and 240 mg of FeS, 27 mg SnPP and 240 mg of FeS, 45 mg 
SnPP and 240 mg of FeS, 63 mg SnPP and 240 mg of FeS, or 90 mg SnPP and 240 mg of FeS 
will be administered on Study Day 1. Subjects will receive FeS by IV infusion and SnPP by direct 
“push” infusion over a 120-minute period. The infusions will be given using a syringe pump over 
a 120-minute period. 
Rationale for the Dose and Schedule Selection: 
The proposed RBT-1 doses and administration schedules are based on previous human studies 
with SnPP and FeS and preclinical pharmacology and toxicology data. The proposed starting dose 
of 9 mg SnPP is 1/10th the NOAEL in rats and 1/36 the NOAEL in dogs based on body surface 
scaling in accordance with the conversion factors in Appendix 1 of the Guidance for Industry 
Estimating the Maximum Safe Starting Dose in Initial Clinical Trials for Therapeutics in Adult 
Healthy Volunteers (2005) and a human body weight of 60 kg, and has previously been 
administered safely to human subjects. 
Study Duration: 
Study duration is for 281 days per subject. 
Criteria for Evaluation: 
Biomarkers 
• 
Key parameters: Blood levels of Haptoglobin, Ferritin, Transferrin Saturation, 
Hemopexin, IL-10, Heme Oxygenase 1 (HO-1) and Bilirubin. Urine samples will also be 
analyzed for subject responsiveness to RBT-1 therapy. 
• 
Additional secondary parameters: p21 
Pharmacodynamic/Safety parameters 
• 
Blood Urea Nitrogen (BUN), Creatinine, Cystatin-C, Kidney Injury Molecule-1 (KIM-1), 
Neutrophil Gelatinase-Associated Lipocalin (NGAL), Albuminuria, N acetyl-beta-D- 
glucosaminidase (NAG), Liver Enzymes and Troponin I  
• 
Adverse events, serious adverse events, suspected adverse reactions, and serious 
unexpected suspected adverse reactions 
• 
Laboratory safety data, vital signs, and temperature at regular intervals 
Pharmacokinetics 
• 
SnPP 
Study Hypothesis: 
It is hypothesized that RBT-1 is safe and well tolerated up to the top dose of 90 mg SnPP along 
with 240 mg of FeS. It is also hypothesized that RBT-1 will modulate biomarker levels in a dose- 
related fashion. 
Statistical Considerations 
Sample Size: No formal sample size calculation has been performed for this phase 1b study. 
However, it is believed that six subjects per dose group in the healthy volunteer cohorts (3) and 
the CKD stages 3 & 4 cohorts (2 each) will be adequate to establish POC based on biomarker 
response and identify an optimal dose for further testing, recognizing that a battery of different 
surrogate biomarkers will be evaluated 

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Analysis Populations and General Methodology: All subjects who receive study medication 
will be included in the Safety population for safety analysis. Subjects who receive study 
medication and have a post-baseline efficacy assessment will be included in the Modified Intent- 
to-Treat (MITT) population for efficacy analysis. All subject data will be listed. When 
appropriate, summary statistics will be provided (number of non-missing values, mean, median, 
standard deviation, minimum, and maximum for continuous variables and number and percentage 
of subjects for categorical variables) by treatment group for all measures, including demographic 
and baseline assessments, safety, and efficacy endpoints. Baseline for all safety and efficacy 
endpoints is defined as the last observations before administration of the first IV infusion of study 
drug. No imputation will be used for missing data. 
Safety Analysis: Safety measures including AEs, infusion-related reactions, clinical laboratory 
tests, vital signs, physical exams, and concomitant medication usage will be summarized 
descriptively by treatment group and study visit, where appropriate. 
Biomarker Analysis: Biomarker response will be summarized by treatment group and study 
visit, comparing change from baseline at 2, 4, 8, 12, 18, 24, 48, 72, 96 and 168 hours after start of 
infusion. 
Percent change from baseline will be analyzed using the mixed model for repeated measures 
(MMRM). The between-group comparison will be performed using the simple contrast at 2, 4, 8, 
12, 18, 24, 48, 72, 96 and 168 hours post-dosing 
In addition to absolute and percent changes from baseline, a responder analysis will also be 
considered. The responder definition and its appropriate analysis methodology will be detailed in 
the statistical analysis plan (SAP) for the study. Exploratory analysis using Cochran-Mantel- 
Haenszel test stratified by baseline or primary diagnosis will be carried out. 
Pharmacokinetic Analysis: Pharmacokinetic parameters of each treatment group will be 
estimated using a non-compartmental analysis following completion of each dose and prior to 
dose escalation. The maximum serum concentration (Cmax) and time to maximum serum 
concentration (Tmax) will be obtained directly from the data. The elimination rate constant (λz), 
elimination half-life (t1/2), area under the concentration-time curve from time 0 to time t (AUC[0- 
t]) and area under the concentration-time curve from time 0 to infinity (AUC[0-inf]), clearance 
(CL), and volume of distribution (Vz) will be calculated for each subject and summarized by 
treatment group. The renal excretion and renal clearance (CL) of tin will also be calculated. 
A compartmental model may be fit to the data if appropriate and used to predict plasma 
concentration-time profiles for other doses and regimens 

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5 EVENT SCHEDULE 
5.1 
Event Schedule – Cohorts 1-7 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1 
Day 8 visit will occur ( 1) days and End of Study (EOS) visit will occur 28 ( 1) days after administration of SnPP. 
2 
Baseline parameters performed prior to dosing on Study Day 1. 
3 
Two ECG’s will be performed on Study Day 1: the first at Baseline (prior to infusion) and the second within 10 minutes of infusion completion. 
4 
Blood samples for SnPP pharmacokinetic analysis will be assessed prior to infusion and 1, 2, 3, 4, 6, 8, 12, 18, and 24, hours (±15 minutes) after start of infusion. 
Additional biomarker samples will also be collected at 2, 4, 8, 12, 18 hours (±15 minutes) after start of RBT-1. Urinary tin excretion will be measured on a 24-hour urine 
sample. 
5 
Subjects will be confined in the clinical testing unit a minimum of 24 hours from the morning of Study Day 1 until after collection of the 24-hour post-dose sample on 
Study Day 2. 
6 
RBT-1 will be administered by infusion over 120-minutes after Baseline ECG, vital signs and blood and urine samples are collected. 
7 
Discharge from unit following evaluations and sample collection required on Study Day 2 
8 
Measured fasting (nothing by mouth except water, coffee or tea, with or without milk and/or sugar, and essential medications only for a minimum of 8 hours prior to sample 
collection at the clinic). 
9 
Parameters to be measured are detailed in Appendix 1. 
10 For women of childbearing potential using kits supplied by the laboratory 
11 Haptoglobin, Ferritin, transferrin saturation, Bilirubin, Hemopexin, IL-10, P21 and HO-1. 
12 Cystatin-C, IL-6, SnPP, Total Porphyrin, Tin, Troponin I, Albuminuria, Kidney Injury Molecule-1 (KIM-1), Neutrophil Gelatinase-Associated Lipocalin (NGAL), N 
acetyl-beta-D-glucosaminidase (NAG), (in addition to BUN and Creatinine which are part of the Serum Chemistry panel) 
13 Three measurements (screening, Day-1, and SD1 prior to dosing) will be taken for the urinary safety biomarkers (Albuminuria, Kidney Injury Molecule-1 (KIM-1), Neutrophil 
Gelatinase-Associated Lipocalin (NGAL),and N acetyl-beta- D-glucosaminidase (NAG)), eGFR, and response biomarkers prior to dosing. 
14 Measurement will be taken for the urinary safety biomarkers (albuminuria, Kidney Injury Molecule-1 (KIM-1), Neutrophil Gelatinase-Associated Lipocalin (NGAL) and N 
acetyl-beta-D-glucosaminidase (NAG)). 
** Day 14 safety evaluation will be conducted at the request of the DSMB after each cohort safety review 
*** Day 60 follow-up on any treatment related adverse event that persisted at Day 29 (i.e., photosensitivity, etc.) or new onset treatment related adverse events. 
Study Day 
Screening 
-1 
1 
2,3,4,5,81 
14** 
28( ±1) 
End of   
Study1 
60(±1) 
TRAE 
Follow-up*** 
Parameter 
Within 14 days 
prior to first dose 
 
 
Written informed consent 
X 
 
 
Eligibility criteria 
X 
 
 
Demographics 
X 
 
 
Medical history 
X 
 
 
Physical examination and weight 
X 
X2 
X 
 
Electrocardiogram 
X 
X2,3 
X 
 
Vital signs 
X 
X2 
X 
X 
 
Serum chemistry8,9 
X 
X2 
X 
X 
 
Hematology8,9 
X 
X2 
X 
X 
 
Baseline determination13 
X 
X 
X 
 
 
Response biomarkers8,11 
X 
X2,4 
X 
 
 
Safety biomarkers8,12 
X 
X2 
X 
X 
X 
 
SnPP PK4,11 
X 
 
 
Urinalysis including sediment9 
X 
X14 
X2 
X 
X 
 
Urine pregnancy test10 
X 
X 
X at Day 8 
X 
 
Urine drug/cotinine screen, 
alcohol (breath) 
X 
 
 
Confinement in clinical testing 
unit5 
X5 
 
 
RBT-1 infusion 
X6 
 
 
Discharge from clinical testing 
unit 
X7 
 
 
Prior/Concomitant medications 
X 
X 
X 
X 
 
Adverse events 
X 
X 
X 
X 
Investigational product 
reconciliation 
X 
 

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5.2 
Event Schedule – Cohorts 8 -10 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1 
Day 8 visit will occur ( 1) days and End of Study (EOS) visit will occur 28 ( 1) days after administration of SnPP. 
2 
Baseline parameters performed prior to dosing on Study Day 1. 
3 
Two ECG’s will be performed on Study Day 1: the first at Baseline (prior to infusion) and the second within 10 minutes of infusion 
completion. 
4 
Blood samples for SnPP pharmacokinetic analysis will be assessed prior to infusion and 1, 2, 3, 4, 6, 8, 12, 18, and 24, hours (±15 minutes) 
after start of infusion. Additional biomarker samples will also be collected at 2, 4, 8, 12, 18 hours (±15 minutes) after start of RBT-1. 
Urinary tin excretion will be measured on a 24-hour urine sample. 
5 
Subjects will be confined in the clinical testing unit a minimum of 24 hours from the morning of Study Day 1 until after collection of 
the 24-hour post-dose sample on Study Day 2. 
6 
RBT-1 will be administered by infusion over 120-minutes after Baseline ECG, vital signs and blood and urine samples are collected. 
7 
Discharge from unit following evaluations and sample collection required on Study Day 2 
8 
Measured fasting (nothing by mouth except water, coffee or tea, with or without milk and/or sugar, and essential medications only for a 
minimum of 8 hours prior to sample collection at the clinic). 
9 
Parameters to be measured are detailed in Appendix 1. 
10 For women of childbearing potential using kits supplied by the laboratory 
11 Haptoglobin, Ferritin, transferrin saturation, Bilirubin, Hemopexin, IL-10, P21 and HO-1. 
12 IL-6, Tin, Troponin I, Albuminuria, (in addition to BUN and Creatinine which are part of the Serum Chemistry panel) 
13 Three measurements (screening, Day-1, and SD1 prior to dosing) will be taken for the urinary safety biomarkers (Albuminuria, eGFR, and 
response biomarkers prior to dosing. 
14 Measurement will be taken for the urinary safety biomarkers (albuminuria,). 
*** Day 60 follow-up on any treatment related adverse event that persisted at Day 29 (i.e., photosensitivity, etc.) or new onset treatment related adverse events. 
Study Day 
Screening 
-1 
1 
2,3,4,5,81 
28( ±1) 
End of   
Study1 
60(±1) 
TRAE 
Follow-up*** 
Parameter 
Within 14 days 
prior to first dose 
 
 
Written informed consent 
X 
 
 
Eligibility criteria 
X 
 
 
Demographics 
X 
 
 
Medical history 
X 
 
 
Physical examination and weight 
X 
X2 
X 
 
Electrocardiogram 
X 
X2,3 
X 
 
Vital signs 
X 
X2 
X 
X 
 
Serum chemistry8,9 
X 
X2 
X 
X 
 
Hematology8,9 
X 
X2 
X 
X 
 
Baseline determination13 
X 
X 
X 
 
 
Response biomarkers8,11 
X 
X2,4 
X 
 
 
Safety biomarkers8,12 
X 
X2 
X 
X 
 
SnPP PK4,11 
X 
 
 
Urinalysis including sediment9 
X 
X14 
X2 
X 
X 
 
Urine pregnancy test10 
X 
X 
X at Day 8 
X 
 
Urine drug/cotinine screen, 
alcohol (breath) 
X 
 
 
Confinement in clinical testing 
unit5 
X5 
 
 
RBT-1 infusion 
X6 
 
 
Discharge from clinical testing 
unit 
X7 
 
 
Prior/Concomitant medications 
X 
X 
X 
X 
 
Adverse events 
X 
X 
X 
X 
Investigational product 
reconciliation 
X 
 

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6 INTRODUCTION 
6.1 
Background Information 
Acute kidney injury (AKI) is an abrupt loss of kidney function in which the body accumulates 
waste products and is unable to maintain electrolyte, acid-base, and water balance [Tögel 2014]. 
It is a major risk factor for morbidity, mortality, and the development of chronic kidney disease 
(CKD) [Goldberg 2009, Ishani 2009, Liangos 2006, Wald 2009, Xue 2006]. A meta-analysis of 
154 studies conducted worldwide in over 3.5 million subjects reported pooled incidence and 
mortality rates of AKI in hospitalized adult subjects of 21.6% and 23.9%, respectively 
[Susantitaphong 2013]. In cardiac surgery subjects, the incidence of postoperative AKI is 
approximately 30% and significantly increases the risk of death after cardiac surgery [Rosner 
2006]. Progression to advanced-stage CKD within 24 months occurs in approximately 15 to 20% 
of subjects who survive AKI [Chawla 2012]. 
 
Many different types of exposure may cause AKI; however, the chance of developing AKI after 
exposure depends on a number of susceptibility factors that vary widely among individual 
subjects [Kellum 2013]. Sepsis, critical illness, circulatory shock, burns, trauma, cardiac surgery 
(particularly with cardiopulmonary bypass), major non-cardiac surgery, nephrotoxic drugs, 
radiocontrast agents, and poisonous plants and animals are all recognized as causes of 
AKI. Susceptibility factors that increase a subject’s risk of developing AKI include dehydration 
or volume depletion, advanced age, female gender, Black race, chronic kidney disease, chronic 
disease (heart, lung, liver), diabetes mellitus, cancer, and anemia. AKI can lead to a number of 
complications, including metabolic acidosis, hyperkalemia, uremia, changes in body fluid 
balance, and effects on other organ systems, including need for dialysis and possibly death. 
People who have experienced AKI have an increased risk of developing chronic kidney disease 
possibly requiring dialysis in the future. The annual cost to the US health care system is 
estimated at approximately $15B [Silver 2017]. 
 
The diagnosis of AKI is based on the following criteria introduced by the Kidney Disease: 
Improving Global Outcomes (KDIGO) AKI Work Group in 2012 [KDIGO 2012]: increase in 
serum creatinine ≥ 0.3 mg/dL within 48 hours; or increase in serum creatinine ≥ 1.5 times 
baseline, which is known or presumed to have occurred within the prior 7 days; or urine volume 
< 0.5 mL/kg/hour for 6 hours. The management of AKI is purely symptomatic, with the aim of 
limiting damage and preventing further loss of function. No pharmacologic therapy is approved 
for the treatment or prevention of AKI. 
 
It has long been recognized that after an initial ischemic or toxic injury, the kidney develops 
marked resistance to subsequent damage [Honda 1987, Zager 1984, Zager 1995a, Zager 1995b, 
Zager 1995c]. This phenomenon, which is mediated in part by an upregulation of renal 
cytoprotective and anti-inflammatory stress proteins (e.g., heme oxygenase 1 [HO-1], ferritin, 
haptoglobin, hemopexin, alpha 1 antitrypsin, interleukin 10 [IL-10]), has been referred to as 
“ischemic preconditioning” or “acquired cytoresistance.” This phenomenon could be used in a 
clinical setting to preemptively protect organs, especially when a known insult is approaching. 

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6.2 
Study Drug 
A pharmacological intervention with the ability to stimulate the kidney’s natural protective 
pathways to prevent AKI would represent a significant medical advance. RBT-1 is under 
development as a prophylactic agent to induce cytoresistance in organs when a known insult is 
imminent. The initial target for development is the kidneys and prevention of AKI. However, 
the phenomenon of acquired cytoresistance is also relevant to other bodily organs such as the 
heart and liver, and will be the focus of extended development of RBT-1 
 
RBT-1 is comprised of 2 different compounds, iron sucrose and stannous protoporphyrin (SnPP). 
Iron sucrose is an intravenous iron replacement product that has been in use for more than 65 
years and is currently registered in more than 90 countries worldwide. In the United States, iron 
sucrose is approved for the treatment of iron deficiency anemia in pediatric and adult CKD 
subjects [Venofer 2015], with expanded indications (i.e., need for rapid iron supply, subjects 
unable to tolerate or comply with oral iron therapy, subjects with inflammatory bowel disease in 
whom oral iron therapy is ineffective) approved for use outside the United States [Venofer 
2016]. Tin protoporphyrin, a potent competitive inhibitor of heme oxygenase activity, is not 
commercially available, but has been safely administered to healthy volunteers [Anderson 1986, 
Berglund 1988, Emtestam 1993], term newborns with hyperbilirubinemia [Kappas 1988], and 
adult subjects with hepatic dysfunction affecting heme metabolism or bilirubin conjugation 
[Anderson 1986, Berglund 1990] or porphyria [Dover 1993, Galbraith 1989]. 
 
 
 
6.3 
Preclinical Experience 
RBT-1 has been shown to induce profound renal preconditioning and the emergence of a 
cytoprotective state in animal models that resulted in marked protection against diverse forms of 
AKI [Zager 2016]. In contrast to ischemic preconditioning, which induces local or remote 
ischemia, the acquired cytoresistance induced by RBT-1 was achieved without resultant damage 
to the kidney, liver, or heart. Thus, these data suggest that RBT-1 may provide a clinical 
prophylactic strategy for protecting against both renal and extrarenal injuries prior to an insult, 
such as exposure to surgery, balloon angioplasty, or administration of a radiocontrast agent. 
 
Initial non-clinical pharmacology and toxicology studies have been conducted and are detailed in 
the Investigator’s Brochure. Single-dose acute toxicity studies of intravenous RBT-1 
demonstrated no-adverse-effect-levels of 25 mg/kg iron sucrose/10 mg/kg SnPP in the rat and 
7.5 mg/kg iron sucrose/3 mg/kg SnPP in the dog. Single-extended acute dose toxicity studies of 
intravenous SnPP demonstrated no-adverse-effect-levels of 10 mg/kg SnPP in the rat (human 
equivalent does of 96 mg) and the dog (human equivalent dose of 324 mg). 
 
6.4 
Clinical Experience 
The current protocol represents the first in human study with RBT-1 and serves as an important 
dose-finding study in both healthy volunteers and subjects with Stage 3-4 CKD.  This study will 
be conducted in compliance with the protocol, good clinical practice (GCP), and the applicable 

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regulatory requirements (including International Conference on Harmonisation [ICH] 
guidelines). 
Safety data in humans are available for the individual components of RBT-1. The most common 
adverse reactions (≥ 2%) following the administration of iron sucrose are diarrhea, nausea, 
vomiting, headache, dizziness, hypotension, pruritus, pain in extremity, arthralgia, back pain, 
muscle cramp, injection site reactions, chest pain, and peripheral edema [Venofer 2015]. Safety 
data from intravenous SnPP administration at doses up to 3 mg/kg has shown photosensitivity in 
subjects when exposed to sunlight or UV-A light following dosing [Anderson 1986, Berglund 
1990, Dover 1993, Galbraith 1989, Kappas 1988]. No other adverse effects of SnPP 
administration have been consistently reported in the literature. 
Safety data from intravenous SnPP administration at doses up to 3 mg/kg has shown 
photosensitivity in subjects when exposed to sunlight or UV-A light following dosing [Anderson 
1986, Berglund 1990, Dover 1993, Galbraith 1989, Kappas 1988]. No other adverse effects of 
SnPP administration have been consistently reported in the literature. 
Some subjects who have been given SnPP have become nauseous and sensitive to sunlight and 
ultraviolet light. This is known as photosensitivity and can last up to a few days or weeks. 
For the entire length of the study, including the End Of Study (EOS) visit through Day 60 
follow-up, patients are advised to: 
• 
Wear a broad-spectrum sunscreen that is at least SPF 30, even on cloudy or cool days and 
to reapply sunscreen every 2 hours. 
• 
It should be applied one-half hour before going outside, giving the skin time to absorb it. 
Because sunscreen tends to be broken down over time by the sun and rubbed or washed 
off with sweating and water exposure, it should be reapplied at least every two hours 
outdoors, and immediately after swimming or heavy sweating. At least one ounce (two 
tablespoons) is needed to cover the entire body surface 
• 
Avoid direct sunlight between 10am and 3pm. Instead, sit in the shade. 
• 
Do not use tanning beds. 
• 
Wear long sleeves, pants, or long skirts when you are in the sun. 
• 
Wear a hat with a wide brim all the way around to shade your face, ears, and neck. 
• 
Wear sunglasses. 

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7 STUDY OBJECTIVES 
7.1 
Primary Objectives 
The primary objectives of the study are to evaluate: 
1. The safety and tolerability of RBT-1 in healthy volunteers and in subjects with stage 3-4 
CKD. 
2. The effect of RBT-1 on biomarkers which are potential surrogates for cytoprotective 
activity in healthy volunteers and in subjects with stage 3-4 CKD. 
3. To establish the optimal dose for testing in subjects at risk for developing AKI. 
4. To study the Pharmacokinetics of SnPP when combined with FeS 
 
8 INFORMED CONSENT 
The investigator or designee will be responsible for obtaining a signed, written informed consent 
form (ICF) and providing a copy to each subject, legally authorized guardian, or a person with 
legal responsibility for the subject’s health care decisions prior to the performance of any clinical 
activities or procedures pursuant to this protocol. Subjects who are vision impaired may have the 
ICF read to them and their witnessed consent documented. Only the consent form approved by 
the Institutional Review Board (IRB)/Independent Ethics Committee (IEC) will be used. If 
English is NOT the subject’s primary language, the subject will be consented using an IRB- 
approved ICF in the requisite language. This consent will be conducted by a member of the 
research team who is fluent in the language and thus able to answer any scientific or procedural 
questions raised by a non-English speaking subject. 
Subject identity should be confirmed by the presentation of a photo identification to ensure the 
correct individual is consented, screened, and enrolled (if eligible). 
 
Only the PID, subject initials, and demographics will be recorded in the eCRF. If the subject 
name appears on any source document collected (e.g., hospital discharge summary), it must be 
removed from the document if the document will be viewed by the Sponsor or a sponsor- 
contracted study vendor not permitted access to subject identifying information. All study 
findings will be stored in electronic databases. The subjects will give explicit written permission 
for representatives of the Sponsor, regulatory authorities, and the IRB to inspect their medical 
records to verify the information collected. Subjects will be informed that all personal 
information made available for inspection will be kept confidential to the extent permitted by all 
applicable state, local, and federal data protection/privacy laws and/or regulations and will not be 
made publicly available. If the results of the trial are published, the subject’s identity will remain 
confidential. 
 
At study check-in to the study site, subjects will be advised not to share their study information 
with other subjects. 

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9 STUDY POPULATION 
9.1 
Healthy Volunteer (HV) 
9.1.1 HV Inclusion Criteria 
• Male and female subjects age 18 to 80 years (inclusive, at time of signing the informed 
consent form. 
• Body weight <125 kg. 
• Able and willing to comply with all study procedures. 
• Female subjects must be either post-menopausal for at least 1 year or surgically sterile 
(tubal ligation, hysterectomy or bilateral oophorectomy) for at least 3 months, or if of 
childbearing potential, have a negative pregnancy test and agree to use dual methods of 
contraception, or abstain from sexual activity from Screening until 29( ±1) days after 
study drug administration. 
Male subjects with female partners of childbearing potential must agree to use a highly 
effective method of contraception from screening until 28(±1) days after study drug 
administration. All fertile men with female partners of childbearing potential should be 
instructed to contact the Investigator immediately if they suspect their partner might be 
pregnant (e.g., missed or late menstrual period) at any time during study participation. 
9.1.2 HV Exclusion Criteria 
• History of malignancy except carcinoma in situ in the cervix, early stage prostate cancer 
or non-melanoma skin cancers. Cancer free for less than 5 years 
• Use of investigational drugs or participation in another clinical trial within 30 days or 5 
half-lives prior to screening, whichever is longer. 
• Serum ferritin > 500 ng/ml or who have received IV iron within 28 days of screening. 
• Women who are pregnant, breastfeeding, or planning to become pregnant while 
participating in the study. 
• Any significant acute or chronic diseases. 
• Subjects with abnormal baseline liver tests or hepatitis serologies that suggest active 
infection. 
• Regular use of drugs of abuse and/or positive findings on urinary drug screening. 
• Current tobacco use and/or positive findings on urinary cotinine screening. 
• Subjects who are severely physically or mentally incapacitated and who, in the opinion of 
investigator, are unable to perform the subjects’ tasks associated with the protocol. 
• Presence of any condition which, in the opinion of the investigator, places the subject at 
undue risk or potentially jeopardizes the quality of the data to be generated. 
• Subjects with history of photosensitivity or active skin disease 
• Known hypersensitivity or previous anaphylaxis to Fes, SnPP or tin based products. 

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9.2 
CKD Subjects 
9.2.1 CKD Inclusion Criteria 
1. Male and female subjects age 18 to 80 years (inclusive, at time of ICF). 
2. Body weight <125 kg. 
3. Able and willing to comply with all study procedures. 
4. Female subjects must be either post-menopausal for at least 1 year or surgically sterile 
(tubal ligation, hysterectomy or bilateral oophorectomy) for at least 3 months, or if of 
childbearing potential, have a negative pregnancy test and agree to use dual methods of 
contraception, or abstain from sexual activity from Screening until 28 days after study 
drug administration. 
Male subjects with female partners of childbearing potential must agree to use a highly 
effective method of contraception from screening until 28 days after study drug 
administration. All fertile men with female partners of childbearing potential should be 
instructed to contact the Investigator immediately if they suspect their partner might be 
pregnant (e.g., missed or late menstrual period) at any time during study participation. 
5. CKD stage 3 as determined by a eGFR between 30-59 ml/min as estimated using the 
CKD-EPI equation. 
6. CKD stage 4 as determined by a eGFR between 15-29 ml/min as estimated using the 
CKD-EPI equation. 
9.2.2 CKD Exclusion Criteria 
• History of malignancy except carcinoma in situ in the cervix, early stage prostate cancer 
or non-melanoma skin cancers. Cancer free for less than 5 years. 
• Use of investigational drugs or participation in another clinical trial within 30 days or 5 
half-lives prior to screening, whichever is longer. 
• Serum ferritin > 500 ng/ml or who have received IV iron within 28 days of screening. 
• Women who are pregnant, breastfeeding, or planning to become pregnant while 
participating in the study. 
• Regular use of drugs of abuse and/or positive findings on urinary drug screening. 
• Current tobacco use and/or positive findings on urinary cotinine screening. 
• Subjects who are severely physically or mentally incapacitated and who, in the opinion of 
investigator, are unable to perform the subjects’ tasks associated with the protocol 
• Presence of any condition which, in the opinion of the investigator, places the subject at 
undue risk or potentially jeopardizes the quality of the data to be generated. 
• Subjects with abnormal baseline liver tests or hepatitis serologies that suggest active 
infection. 
• 
Subjects with CKD and not at their baseline of renal function and have significant acute 
or chronic illnesses. 
• Subjects with history of photosensitivity or active skin disease 

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• Known hypersensitivity or previous anaphylaxis to FeS, SnPP or tin based products. 
9.3 
Study Design 
This is a Phase 1b, single-center, dose-escalating study to evaluate the safety, tolerability, PK and 
pharmacodynamic effect of RBT-1 in healthy volunteers and in subjects with stage 3-4 CKD. The 
following biomarkers will be used as surrogate measures of protective activity: Haptoglobin, Ferritin, 
Transferrin Saturation, Bilirubin, Hemopexin, IL-10, p21 and HO-1. 
Screening data will be reviewed to determine subject eligibility. Subjects who meet all inclusion 
criteria and none of the exclusion criteria are eligible to be enrolled into the study. A baseline for 
safety and response biomarkers will be established by taking three measurements between screening 
and prior to dosing. 
The study is designed as follows: 
• A screening period with baseline evaluations for study eligibility. 
• If subjects meet eligibility criteria, they will receive FeS by IV infusion and SnPP by direct 
“push” infusion over a 120-minute period on SD 1. 
• Subjects will stay in the clinic for the initial 24 hours after administration of RBT-1 and will be 
discharged on SD 2 if no safety issues appear. 
• Study will initially be dose-escalating in 3 groups of 6 healthy volunteers each, for a total of 18 
healthy volunteers, evaluating escalating single doses of SnPP administered with FeS starting 
with a dose of 9 mg SnPP and 240 mg of FeS, followed by 27 mg SnPP and 240 mg of FeS, 
and 90 mg SnPP and 240 mg of FeS. Dose-escalation from one dose level to the next will only 
be allowed after a careful review of the safety, tolerability and PK data from the prior dose 
group as determined by the Data and Safety Monitoring Board. 
• After a careful review of the safety, tolerability and PK data from all dose groups from the 
healthy volunteer cohorts, the Data and Safety Monitoring Board (DSMB) will determine 
whether to proceed to the CKD cohorts. If the determination by the DSMB allows to proceed 
to the CKD cohorts, subjects with stage 3 CKD will be in 2 groups of 6 each, for a total of 12 
subjects, evaluating escalating single dose of RBT-1 starting with a dose of 27 mg SnPP and 
240 mg of FeS followed by 90 mg SnPP and 240 mg of FeS. Dose-escalation from one dose 
level to the next will only be allowed after a careful review of the safety, tolerability and PK 
data from the prior dose group as determined by the Data & Safety Monitoring Board. 
• After a careful review of the safety, tolerability and PK data from all dose groups from the 
stage 3 CKD cohorts, the Data and Safety Monitoring Board (DSMB) will determine whether 
to proceed to the stage 4 CKD cohorts. If the determination by the DSMB allows to proceed to 
the stage 4 CKD cohorts, subjects with stage 4 CKD will be in 2 groups of 6 each, for a total of 
12 subjects, evaluating escalating single dose of SnPP starting with a dose of 27 mg SnPP and 
240 mg of FeS followed by 90 mg SnPP and 240 mg of FeS. Dose-escalation from one dose 
level to the next will only be allowed after a careful review of the safety, tolerability and PK 
data from the prior dose group as determined by the Data and Safety Monitoring Board. 
• Once the first 7 cohorts have been enrolled, the study may enroll additional patients in one of 
three dose levels starting at the dose of 63 mg SnPP and 240 mg of FeS for CKD patients.  
After a safety and biomarker response evaluation, CKD patients may be dosed at 45 mg SnPP 
and 240 mg of FeS.  Healthy and CKD patients may be dosed at 90 mg SnPP and 240 mg of 
FeS.  

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• The infusions will be given over a 120-minute period using an infusion pump and a syringe 
pump. 
• Subjects will be followed for 281 days after the dose of RBT-1. Response and Safety 
biomarkers will be assessed at baseline and (2, 4, 8, 12, 18, response biomarkers only) 24, 48, 
72, 96 and 168 hours after study drug administration. Safety biomarkers will be assessed for up 
to 281 days after study drug administration. Urine samples will be collected and centrifuged 
and analyzed for subject responsiveness to RBT-1 therapy. 
• Blood samples for pharmacokinetic analysis will be collected prior to infusion and 1, 2, 3, 4, 6, 
8, 12, 18 and 24 h post start of infusion. 
• Urinary excretion of SnPP will be assessed over 24-hour urine sample by measuring tin in 
urine 
• Total study duration will be up to 601 days per subject. 
9.3.1 Stopping Rules 
There are no pre-established stopping rules for the study. 
9.4 
Recordkeeping and Monitoring 
All subject data will be reported in the electronic data capture (EDC) system with the exception of the 
laboratory reports, which will be uploaded by electronic transfer by the laboratory. All original source 
documents should be available for periodic monitoring and/or retrieval by a Sponsor representative 
designee. The investigator is responsible for the accuracy of all data entered in the electronic case 
report forms (eCRFs) and for the timely completion of the electronic case report forms. The 
supporting documentation will be maintained at the site for a minimum of two (2) years following 
notification by Renibus Therapeutics, Inc. to the FDA of the termination of the entire investigation. 
The Sponsor must be contacted and give written authorization prior to any study records being 
destroyed at investigative sites. 
This study will be conducted in compliance with Good Clinical Practice (GCP), which includes the 
Sponsor and Institutional Review Board (IRB) -approved protocol and ICF and the FDA and 
International Conference on Harmonisation (ICH) regulatory guidelines and requirements. No changes 
will be made without prior approval unless it is imperative for subject safety. Any such departures 
from the protocol will be reported immediately to the Sponsor and relevant IRB. 
All subjects’ medical records and study-related documents will be made available to the Sponsor for 
regular monitoring and audits as well as to the IRB and FDA or other governmental agency with 
oversight or compliance responsibilities for assuring subject rights and welfare. 
9.5 
Investigational Supplies 
Subjects will be dosed with open-label RBT-1. 
9.5.1 Study Drug Description 
The investigational product is a combination of Stannous protoporphyrin IX dichloride (SnPP) in a 
solution of sodium hydroxide and an iron sucrose solution buffered with sodium bicarbonate (FeS). 
The term investigational product refers to RBT-1. 
9.5.2 Packaging 
The two components of the investigational product (FeS and SnPP) will be packaged and labeled in 

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separately filled vials of 5 ml at Patheon, Inc. Iron sucrose will be packaged in a clear vial, SnPP will 
be packaged in a clear vial protected from light 
Following receipt of Form FDA 1572 and IRB approval for a given site, investigational product will 
be sent to the study site. 
9.5.3 Investigational Product Dispensing 
All investigational product will be dispensed by designated and trained site pharmacy staff. 
9.5.4 Dosage Preparation and Administration 
The vials of RBT-1(FeS and SnPP) components will be administered via IV infusion. The FeS 
component will be administered with up to 250mL of saline via infusion pump and the SnPP 
component by direct “push” co-infusion over a 120-minute period 
Total infusion time will be 120 (± 5) minutes as detailed in the Pharmacy Manual. 
Subjects will be observed for signs and symptoms of hypersensitivity during and after administration 
for at least 30 minutes and until clinically stable following completion of each administration. RBT-1 
will only be administered when personnel and therapies are immediately available for the treatment of 
serious hypersensitivity reactions. 
9.5.5 Storage Requirements 
The investigational product should be stored at controlled room temperature conditions (defined as 20 
- 25C/68 - 77F with excursions of less than 24 consecutive hours permitted between 15 - 30C/59 - 
86F) and protected from light. 
9.5.6 Investigational Product Accountability 
The investigator or designee is responsible for maintaining accurate records accounting for the receipt, 
dispensing, and final disposition of all investigational products using the appropriate investigational 
product logs provided by Renibus Therapeutics, Inc. 
9.5.7 Retrieval and Destruction 
Periodically throughout the study, sites will perform investigational product reconciliation on a per-
subject basis. The Renibus site monitor will review the log and once any discrepancies have been 
resolved, authorize destruction/disposition of the supplies associated with a given subject by signing 
the reconciliation log and will witness the destruction/disposition. 
9.6 
Study Visits 
9.6.1 General Information 
• All recorded clock times should utilize a 24-hour clock. 
• In accordance with the clinical site’s standard operating procedures, an intravenous catheter or 
a butterfly needle (of a sufficient gauge to avoid sample hemolysis) may be inserted for the 
purpose of collection of blood samples. Alternatively, the site preference may be to use direct 
venipuncture for the purpose of collection of blood samples. Either method is acceptable. 
• There are no dietary restrictions in this study. Subjects should continue to eat their normal diet. 
• Subjects will not be able to drink alcohol (for example, no liquor, beer or wine) from 24 hours 
prior to dosing until the final blood collection on Day 2. After the final blood collection on 
Day 2, alcohol will be limited to 2 units (1 unit of alcohol is equivalent to 12 ounces of beer, 4 
ounces of wine, or 1 ounce of 50-proof hard liquor) per day until the End of Study or Day 29. 

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• Subjects will be encouraged to remain well hydrated during the study to promote sample 
collection. 
• Blood samples for chemistry, hematology, biomarkers and pharmacokinetic analysis will be 
collected into the appropriate collection tubes and processed in accordance with the 
instructions specified in the laboratory manual. 
• The ICF must be signed before any of the Screening or Study procedures are performed. 
• Subjects will be encouraged to continue to use sun screen products and protect themselves 
from the sun for 60 days after dosing. 
9.6.2 Screening (Within 14 Days Prior to Check-in Day) 
• Subjects will arrive at the clinical testing unit in the morning after fasting (defined as nothing 
by mouth except water) for at least 8 hours prior to the collection of any blood samples. 
• Eligibility will be confirmed. 
• Demographic characteristics and medical history will be obtained. 
• Physical examination (including height and weight), vital signs (after sitting ≥ 5 minutes), and 
12-lead ECG (after sitting ≥ 5 minutes) will be performed. 
• Blood and urine will be collected for clinical laboratory tests, biomarkers and drug/cotinine 
screen (Appendix 1). Alcohol will be breath tested. 
• For women of childbearing potential, urine pregnancy test will be performed. 
• Eligible subjects will return to the clinical testing unit within 14 days for confinement and 
dosing. 
9.6.3 Study Day -1, a day prior to dosing 
• 
Patients will arrive at the clinic at 8:00am (60 minutes) after fasting for at least 8 hours. All 
eligibility criteria will be assessed. 
For CKD subjects, subjects whose GFR value does not meet the inclusion criteria may be re-
screened 2 more times during the trial. If the ICF has been signed within 30 days and there are 
no new revisions, a new ICF is not necessary. If a subject is re-screened, the subject will be 
given a new screening number in the eCRF system and source documents. 
• 
If all eligibility criteria are met, the following Day -1 samples will be collected (Appendix 1): 
• 
Blood samples for measurement of response biomarkers (Haptoglobin, Ferritin, 
Bilirubin, Hemopexin, IL-10, p21 and HO-1). 
• 
Blood samples for measurement of Safety biomarkers (Tin, Total Porphyrins*, IL-6, 
Troponin I and Cystatin-C*). 
• 
Urine for measurement of safety biomarkers (Albuminuria, Cystatin-C*, Kidney Injury 
Molecule-1 (KIM-1)*, Neutrophil Gelatinase-Associated Lipocalin (NGAL)*, and 
NAG*) and for response biomarkers (Hemopexin, Ferritin, p21 and HO-1). 
* Total Porphyrins, Cystatin-C, KIM-1, NGAL and NAG will only be assessed in Cohorts 1 through 7 
9.6.4 Study Day 1 
If all eligibility criteria are met, the following Baseline samples will be collected after fasting for at 
least 8 hours (Appendix 1): 

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• 
Blood samples for standard assessment of hematology and serum chemistry. 
• 
Blood samples for measurement of response biomarkers (Haptoglobin, Ferritin, 
transferrin saturation, Bilirubin, Hemopexin, IL-10, p21 and HO-1). 
• 
Blood samples for measurement of Safety biomarkers (Tin, Total Porphyrins, IL-6, 
Troponin I and Cystatin-C). 
• 
Blood samples for measurement of SnPP. 
• 
Urine for standard assessment of urinalysis parameters and safety biomarkers 
Albuminuria, Cystatin-C, Kidney Injury Molecule-1 (KIM-1), Neutrophil Gelatinase-
Associated Lipocalin (NGAL), and NAG). 
• 
Urine samples for measurement of response biomarkers (Hemopexin, Ferritin, p21 and 
HO-1), and for urinary clearance of SnPP. Urine samples will be collected and centrifuged 
and analyzed for subject responsiveness to RBT-1 therapy. 
* Total Porphyrins, Cystatin-C, KIM-1, NGAL and NAG will only be assessed in Cohorts 1 through 7 
1. A Baseline ECG will be performed (Section 9.8.1). 
2. A full physical examination including height, weight, and vital signs will be performed 
(Sections 9.8.3 and 9.8.4). 
3. Medical history and prior/concomitant medication information will be collected. (Section 
9.8.2) 
4. Subjects who meet all inclusion/exclusion criteria will be enrolled into the Study and the 
following procedures will take place: 
• The dose of RBT-1 will be administered in the clinic as an IV infusion for FeS and a 
“push,” direct infusion for SnPP, over a 120 ± 5-minute period. Food may be given after 
the infusion. 
 
Observe for signs and symptoms of hypersensitivity during and after administration for 
at least 30 minutes and until clinically stable following completion of each administration. 
Only administer when personnel and therapies are immediately available for the 
treatment of serious hypersensitivity reactions. 
Should a subject experience nausea during or after infusion, the investigator may order 
Ondansetron (Zofran®) per its label instructions. Zofran may also be given 
prophylactically if at lower doses nausea is observed in subjects. 
Patients will be advised on other interventions necessary to mitigate the risk of 
phototoxicity such as wearing a hat, sunglasses, long sleeve shirts and sunscreen with an 
SPF 30 when appropriate. 
• A post-infusion ECG will be performed 10 minutes (± 15 minutes) after the end of the 
infusion. 
• The clinic staff will solicit any adverse events. 
• Response biomarker samples (Haptoglobin, Ferritin, transferrin saturation, Bilirubin, 
Hemopexin, IL-10, p21 and HO-1) will be collected at 2, 4, 8, 12, and 18 hours (± 15 
minutes) after the start of the infusion. 
• Blood samples for pharmacokinetic analysis will be collected at 1, 2, 3, 4, 6, 8, 12, 18 and 
24 hours (± 15 minutes) after the start of the infusion. 
• Lunch and dinner will be provided by the clinic. 

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9.6.5 Study Day 2 
The following procedures will be done at 24 hours (± 15 minutes) after dosing: 
• Blood samples for standard assessment of clinical chemistry, hematology, and safety and 
response biomarkers will be collected (Appendix 1). 
• Blood samples for SnPP pharmacokinetic analysis will be collected. 
• Urine samples for standard assessment of urinalysis parameters and response and safety 
biomarkers will be collected (Appendix 1). 
• The clinic staff will solicit any adverse events and note any changes in concomitant 
medications. 
• The subject will be discharged from the clinic per site discharge procedures. 
9.6.6 Study Days 3,4,5,8 (Day 8  1 day) 
• Subjects will arrive at the clinic at 8:00am (± 60 minutes) after fasting for at least 8 hours. 
• Blood samples for standard assessment of clinical chemistry, hematology, and safety and 
response biomarkers will be collected (Appendix 1). 
• Urine samples for standard assessment of urinalysis parameters and response and safety 
biomarkers will be collected (Appendix 1). 
• A urine pregnancy test will be performed if the subject is a woman of childbearing 
potential at Day 8. 
• The clinic staff will solicit any adverse events and note any changes in concomitant 
medications since the last visit. 
9.6.7 Study Day 14 (Cohorts 1-7) 
• Study Day 14 safety review will be conducted at the request of the DSMB after the data 
assessment from each cohort for Cohorts 1 through 7. 
• The clinic staff will solicit any adverse events and note any changes in concomitant 
medications. 
9.6.8 Study Day 28/End of Study Visit (28  1 days following the RBT-1 dose) 
• Subjects will arrive at the clinic at 8:00am (± 60 minutes) after fasting for at least 8 
hours. 
• Blood samples for standard assessment of clinical chemistry, hematology, and 
safety biomarkers will be collected (Appendix 1). 
• Urine samples for standard assessment of urinalysis parameters and safety 
biomarkers will be collected (Appendix 1). 
• A full physical examination including weight and vital signs will be performed 
(Sections 9.8.3 and 9.8.4). 
• The clinic staff will solicit any adverse events and note any changes in concomitant 
medications since the last visit. 
• A urine pregnancy test will be performed if the subject is a woman of childbearing 
potential. 

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9.6.9 Study Day 60 Adverse Event Follow-up (telephone or visit) 
• 
Subjects with persistent treatment related adverse events at Day 28 or new onset 
treatment related adverse events after Day 28 will be collected up to 60 days. If 
after 60 days of study drug administration, an investigator becomes aware of an 
SAE that he or she suspects is related to study drug, the investigator should report it 
to the Sponsor. 
9.7 
Clinical Laboratory Evaluations 
All samples for clinical laboratory evaluations will be collected under fasting conditions, 
defined as nothing by mouth except water, and essential medications only (for CKD patients 
only) for a minimum of 8 hours prior to collection of the samples. 
9.7.1 Blood Chemistry, Hematology, Pharmacokinetic and Response biomarker Samples 
The chemistry, hematology and response and safety biomarker parameters to be evaluated during 
the study are presented in Appendix 1. Detailed instructions regarding sample collection and 
processing are provided in the laboratory manual. Collection times are summarized in the Events 
Schedules (Section 5 and Section 9.6). 
9.7.2 Urine Samples 
The urine parameters, including SnPP urinary excretion, and response and safety biomarkers to 
be evaluated during the Study are presented in Appendix 1. Detailed instructions regarding 
sample collection and processing are provided in the laboratory manual. Collection times are 
found in the Events Schedules (Section 5 and Section 9.6). All urine samples will be analyzed by 
the laboratory, except for urine pregnancy tests for women of childbearing potential. 
All women of childbearing potential (defined as not surgically sterile nor postmenopausal for at 
least 2 years) will have a urine pregnancy test performed at the clinic as part of the screening 
procedure prior to any investigational product administration and at an End of Study using the 
pregnancy kit supplied by the laboratory. 
9.8 
Clinical Procedures and Observations 
The research clinic will follow its own standard operating procedures for the daily ongoing 
monitoring of subjects while subjects are in the clinic (e.g. pulse, O2 saturation, etc.). Subjects 
will be monitored for any adverse events occurring at any time throughout the study. 
9.8.1 
ECG 
ECGs will utilize a 12-lead recording. Collection times are summarized in the Events Schedules 
(Section 5 and Section 9.6). ECG results will be assessed by the investigator/sub-investigator. 
9.8.2 
Concomitant Medications 
All concomitant medications taken by the subject from 30 days prior to Study Day 1 through the 
end of study (28 [ 1] days after the dose of investigational product) will be recorded. 
9.8.3 
Physical Examination 
A full physical examination, including height (Study Day 1 only) and weight (weighed on the 
same scale in the same state of dress), will be conducted at Day 1 and at end of the study. 
Collection times are summarized in the Events Schedules (Section 5 and Section 9.6). 
All physical examinations are to be performed by the investigator/sub-investigator or designee 
whose license permits the performing of physical examinations. 

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9.8.4 
Vital Signs 
Blood pressure (systolic and diastolic), pulse, and body temperature will be measured before 
investigational product is administered and after the subject has been in a sitting position for ≥ 5 
minutes. Collection times are summarized in the Events Schedules (Section 5 and Section 9.6). 
9.8.5 
Meals and Dose Administration 
There are no dietary restrictions in this study. Subjects should continue to eat their normal diet. 
Breakfast may be eaten before or after the infusion of RBT-1 on Study Day 1. 
9.8.6 Prohibited Medications 
Medications which can cause photosensitivity are prohibited for subjects in the Study. 
Oral iron medication may be taken prior to screening but must be discontinued upon enrollment. 
 
10 ADVERSE EVENT REPORTING 
All adverse events will be recorded on the designated study eCRF for each subject beginning 
with the first administration of investigational product and ending 60 days after the date of study 
drug administration. Any unresolved serious adverse events will be followed by the investigator 
until event resolution, the subject is lost to follow-up, the adverse event is otherwise explained or 
not considered clinically significant by the investigator. 
10.1 
Investigator Reporting Requirements 
The investigator must immediately report (within 24 hours by telephone and followed by a 
written report sent by fax or e-mail) all serious adverse events to Renibus Therapeutics, Inc. 
regardless of whether the investigator believes that they are drug related, including those events 
listed in the protocol as anticipated to occur in the study population independent of drug 
exposure (see Section 10.2). 
These serious adverse events must be reported to: 
Bhupinder Singh, MD, FASN, FNKF 
Medical Monitor 
Renibus Therapeutics, Inc 
950 E State Highway 114, Suite 160 
Southlake, TX 76092 
Cell: 
(480) 220-7084 
Fax 
(817) 549-1254 
E-mail: 
medicalmonitor@renibus.com 
Because the investigator is knowledgeable about the human subject (e.g., medical history, 
concomitant medications), administers the investigational drug, monitors the subject’s response 
to the drug, is aware of the subject’s clinical state and thus may be sensitive to distinctions 
between events due to an underlying disease process versus events that may be drug-related, and 
may have observed the event, the investigator must include an assessment of causality (i.e., 
whether there is a reasonable possibility that the drug caused the event) in the report to Renibus 
Therapeutics, Inc. Copies of each report to Renibus Therapeutics, Inc. will be kept in the 
investigator’s study file. 
The investigator is responsible for complying with their IRB’s requirements for reporting serious 

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adverse events. Any expedited safety report (i.e., serious unexpected suspected adverse reaction) 
received from Renibus Therapeutics, Inc. should be submitted to the IRB. Copies of each report 
and documentation of IRB notification will be kept in the investigator’s study file. 
The investigator must record non-serious adverse events in the eCRF and report them to Sponsor 
according to the timetable for reporting (e.g., end of study). The investigator’s assessment of 
causality is not required for non-serious adverse events. 
10.2 
Definitions 
Adverse Event: Adverse event means any untoward medical occurrence associated with the use 
of a drug in humans, whether or not considered drug related. An adverse event can be any 
unfavorable and unintended sign (e.g., an abnormal laboratory finding), symptom, or disease 
temporally associated with the use of a drug, without any judgment about causality. 
Adverse Reaction: Adverse reaction means any adverse event definitely caused by the drug. 
Suspected Adverse Reaction: Suspected adverse reaction means any adverse event for which 
there is a “reasonable possibility” (i.e., evidence indefinite but suggests a causal relationship 
between the drug and the adverse event) that the drug caused the adverse event. By definition, a 
suspected adverse reaction is identical to the definition of adverse drug reaction per ICH E2A. 
Examples that would suggest a causal relationship: 
• A single occurrence of an event that is uncommon and known to be strongly associated 
with drug exposure (e.g., angioedema, hepatic injury, Stevens-Johnson Syndrome) 
• One or more occurrences of an event that is not commonly associated with drug exposure, 
but is otherwise uncommon in the population exposed to the drug (e.g., tendon rupture) 
• An aggregate analysis of specific events observed in a clinical trial (e.g., known 
consequences of the underlying disease or condition under investigation or other events 
that commonly occur in the study population independent of drug therapy) that 
indicates those events occur more frequently in the drug treatment group than in a 
concurrent or historical control group. 
Unexpected Adverse Event or Unexpected Adverse Reaction: An adverse event or adverse 
reaction is considered “unexpected” if it is not listed in the investigator brochure or is not listed 
at the specificity or severity that has been observed. 
Adverse events or adverse reactions that are mentioned as occurring with a class of drugs or as 
anticipated from the pharmacological properties of the drug will be considered “unexpected” if 
they are not specifically mentioned as occurring with the particular drug under investigation. 
Until the investigator brochure is updated to include a new serious suspected adverse reaction, 
subsequent occurrences of similar serious suspected adverse reactions must be submitted 
expeditiously to FDA in IND Safety Reports and to other appropriate regulatory authorities in 
countries other than the US in an Individual Case Safety Report (ICSR) or using a Council for 
International Organizations of Medical Sciences (CIOMS) I form, as appropriate. 
Serious Adverse Event or Serious Adverse Reaction: An adverse event or adverse reaction is 
considered “serious” if, in the view of either the investigator or Sponsor, it results in any of the 
following outcomes: 
• Death 
• A life-threatening adverse event 

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• In subject hospitalization or prolongation of existing hospitalization 
• A persistent or significant incapacity or substantial disruption of the ability to conduct 
normal life functions 
• A congenital anomaly/birth defect. 
Important medical events that may not result in death, be life-threatening, or require 
hospitalization may be considered serious when, based upon appropriate medical judgment, they 
may jeopardize the subject and may require medical or surgical intervention to prevent one of the 
outcomes listed in this definition. 
If either the investigator or Sponsor believes that the event is serious, it must be evaluated by the 
Sponsor for expedited reporting to regulatory authorities. 
Life-Threatening Adverse Event or Life-Threatening Adverse Reaction: An adverse event or 
suspected adverse reaction is considered “life-threatening” if, in the view of either the 
investigator or Renibus, its occurrence places the subject at immediate risk of death. 
Serious Unexpected Suspected Adverse Reaction: An adverse event for which there is a 
reasonable possibility that the drug caused the adverse event, and it is not listed in the 
investigator brochure or is not listed at the specificity or severity that has been observed, and it 
results in any of the serious outcomes listed above. This criterion is consistent with the concepts 
of FDA 21 Code of Federal Regulation (CFR) 312 and the ICH E2A Guideline for expedited 
safety reports. 
The Sponsor must notify the appropriate regulatory authority(ies) and all participating 
investigators in an expedited safety report (e.g., IND Safety Report or ICRS) of potentially 
serious risks from clinical trials or any other source (i.e., a serious unexpected suspected 
adverse reaction), as soon as possible, but no later than 15 calendar days after Renibus 
Therapeutics, Inc. receives the safety information and determines that the information 
qualifies for reporting. 
During the course of drug development, the Sponsor may become aware of new safety 
information from a variety of sources and will decide if an individual case of a serious and 
unexpected adverse event meets the criteria for reporting to regulatory authorities. 
If the adverse event does not meet all criteria (i.e., reasonable possibility of causality, serious and 
unexpected), it should not be submitted as an expedited safety report. 
Any unexpected fatal or life-threatening suspected adverse reaction must be reported to 
regulatory authorities no later than 7 calendar days after Renibus Therapeutics, Inc. receives the 
safety information. 
10.3 
Breaking the Blind 
Not applicable as this is an open label study. 
 
11 
STATISTICAL CONSIDERATIONS 
This section outlines the nature and rationale for the statistical methods to be used for the 
analysis of the data from the study. A separate Statistical Analysis Plan (SAP) will describe data 
handling and statistical techniques in full detail. 
11.1 
Study Populations 

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All subjects who receive study medication will be included in the safety and PD analyses. All 
subjects who receive study medication and provided sufficient and valid serum SnPP 
concentration data to allow the determination of PK parameters will be considered as potential 
PK evaluable subjects. No imputation will be used for missing data. 
11.2 
Demographic and Baseline Characteristics 
Demographic and baseline variables that will be summarized by dose group include: 
• 
Demographics 
• 
Medical history 
• 
Complete PE 
• 
Efficacy and Safety variables including vital signs and laboratory tests, including 
chemistry, hematology, and urinalysis obtained at Screening. 
11.3 
Analysis of Efficacy Endpoints 
Descriptive statistics will be used to summarize Safety and Response biomarker results at 
baseline (Mean of 3 values from Screening, SD-1 and SD1 prior to dosing), each visit, and 
the change from baseline for each visit. 
Percent change from baseline will be analyzed using the mixed model for repeated measures 
(MMRM). In this analysis, percent change from baseline at each post treatment time point will 
be the response variable; treatment, visit, and treatment-by-visit interaction as fixed factors, 
patient as repeated measure unit over visits, and baseline as covariate. The between-group 
comparison will be performed using the simple contrast at 2, 4, 8, 12, 18, 24, 48, 72, 96 and 168 
hours post-dosing. 
 
In addition to the percent changes from baseline, absolute change from baseline will also be 
analyzed using MMRM. Moreover, a responder analysis will also be considered. The 
responder definition and its appropriate analysis methodology will be detailed in the statistical 
analysis plan (SAP) for the study. Exploratory analysis using Cochran-Mantel-Haenszel test 
stratified by baseline or primary diagnosis will be carried out. 
11.4 
Analysis of Pharmacodynamic/Safety Endpoints 
The evaluation of safety will include adverse events, clinical laboratory parameters, safety 
biomarkers, vital signs, physical examinations, and ECGs. 
The principle of treatment emergence will be employed for the analysis of adverse event data. A 
Treatment emergent adverse event (TEAE) is defined to be any event that occurs during the 
observation period of the study and was not present at baseline, or exacerbation of a condition 
present at baseline. 
TEAEs will be classified by the Medical Dictionary for Regulatory Activities (MedDRA). The 
type, incidence, timing (onset, duration), relationship, and severity of adverse events will be 
reported for treatment-emergent and serious adverse events. Reasons for withdrawal due to 
adverse events will also be reported. 
Descriptive statistics, including mean, mean change from baseline, standard deviation, minimum, 
maximum, and median, will be presented for laboratory parameters, vital signs, and ECG 
parameters. The numbers and percentages of subjects with treatment-emergent laboratory, vital 
sign, and ECG values that meet Sponsor-defined potentially clinically significant criteria will be 

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summarized. Categorical (low, normal, and high relative to the normal range) shifts from 
baseline will be summarized with the number and percentage of subjects for laboratory 
parameters. 
All safety data will be displayed in listings. 
11.5 
Analysis of Pharmacokinetic (PK) Data 
Pharmacokinetic (PK) parameters will be calculated for each subject and summarized by 
treatment group. PK profiles in which the pre-dose concentration is equal to or greater than the 
lower limit of quantification (LLOQ) and ≥5% of the corresponding Cmax will be excluded from 
all descriptive statistics and statistical analyses. 
Actual blood sampling times will be used in all PK analyses. Protocol-specified times will be 
used to calculate mean plasma or serum concentrations for tabular and graphical displays. All PK 
calculations and generation of individual subject plasma or serum concentration versus time 
graphs will be performed using SAS®Version 9.4 or higher. 
PK parameters will be calculated for each subject using non-compartmental analysis. The 
parameters will include, where possible, the maximum serum concentration (Cmax) and time to 
maximum serum concentration (Tmax), taken directly from the data, the elimination rate 
constant (λz), elimination half-life (t½), area under the concentration-time curve from time 0 to 
the last time with a concentration ≥ LLOQ (AUC[0-t]) and area under the concentration-time 
curve from time 0 to infinity (AUC[0-inf]), clearance (CL), and volume of distribution (Vz). 
Only plasma samples with concentrations ≥ LLOQ will be used in the PK analysis. Plasma 
concentrations < LLOQ will be taken as 0 for the calculation of the descriptive statistics at each 
sampling time. For the PK analysis, plasma concentrations < LLOQ that occur from pre-dose to 
the first concentration ≥ LLOQ will be taken as 0 and those that occur thereafter will be taken as 
missing. 
Plasma concentrations and PK parameters will be summarized by treatment group using 
descriptive statistics — number of values, arithmetic mean, standard deviation, and coefficient of 
variation, geometric mean and coefficient of variation, minimum, median, and maximum. 
11.6 
Sample Size Calculations 
No formal sample size calculation has been performed for the study. However, it is believed that 
6 subjects per dose group will be adequate to establish POC based on biomarker response and 
identify an optimal dose for further testing, recognizing that a battery of different surrogate 
biomarkers will be evaluated. 
11.7 
Interim Analysis 
No interim analysis is planned. 
 
12 WITHDRAWAL FROM STUDY 
Every reasonable effort should be made to maintain protocol compliance and participation in the 
study. Should a subject withdraw or be prematurely terminated from the study for any reason, the 
reason for early study withdrawal will be recorded. If withdrawal is the result of a serious 
adverse reaction, the subject will be followed until the condition has resolved, as determined by 
the investigator. 
The investigator or Sponsor may withdraw any subject at any time for medical reasons or for 

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administrative reasons (i.e., subjects unable or unwilling to comply with the protocol). If so, the 
subject will be censored at time of withdrawal and, if possible, a final evaluation (End of Study 
procedures) will be made. All treated subjects (those who have received at least 1 dose of 
investigational product) will be included in the ITT and safety analyses. 
In the unlikely event the Sponsor or FDA should determine it is appropriate to terminate the 
study early, every effort will be made for transitioning subjects with minimal disruption to the 
subject and investigator. The IRB will be notified of termination, and reason(s) and procedures 
for follow-up of research subjects will be developed by the study physician in consultation with 
the Sponsor and IRB. 
 
13 
DATA MANAGEMENT 
The standard procedures for handling and processing records will be followed as per GCP and 
the data management standard operating procedures of the contract research organization (CRO). 
A comprehensive Data Management Plan will be developed and approved by a representative of 
the Data Management CRO and the Sponsor. 
13.1 
Database Lock 
The database will be locked in order to protect write access after the following preconditions are 
fulfilled: 
• All data are entered in the database 
• All data queries have been resolved to the satisfaction of the Lead Biostatistician 
• All decisions have been made regarding all protocol violators and ITT population 
exclusions 
• The eCRF will be signed off/approved by the Site Investigator 
• Written authorizations to lock the database are obtained from Renibus Clinical Data 
Management and the Chief Scientific Officer. 
 
14 ETHICAL CONSIDERATIONS 
14.1 
Ethical Conduct of the Study 
The study will be conducted in accordance with United States Title 21 CFR and the ICH E6 (R1) 
Guidelines of Good Clinical Practice. The Declaration of Helsinki and its most recent updates 
(Seoul, 2008) will be observed. 
The investigator will provide the Sponsor/designee with documentation of IRB approval of the 
protocol and the sample informed consent document before the study may begin at the 
investigative site. The IRB will review the protocol as required. 
The investigator will supply the following to the IRB: 
• The current Investigator’s Brochure and updates 
• Study protocol and amendments 
• Informed consent and assent document and updates 

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• Relevant curricula vitae 
• Safety alerts 
• Serious adverse reaction reports 
The investigator must provide the following documentation to the Sponsor or designee: 
• The IRB original approval of the protocol and the informed consent, and re-approval of 
the study (annual or semi-annual, per IRB guidelines) 
• The IRB approvals of any revisions to the informed consent document or amendments to 
the protocol 
• All other documents that are required by local regulatory authorities 
14.2 
Regulatory Considerations 
After reading the protocol, each investigator/sub-investigator will sign a protocol signature page 
and return a copy of the signed page to the Sponsor/designee, while maintaining the original at 
the site. 
14.3 
Protocol Amendments and Study Termination 
The IRB must be informed and give approval for any amendments likely to affect the safety of 
the subjects or the conduct of the study. 
The IRB must be advised in writing of the study’s completion or early termination and a copy of 
the notification must be provided to the Sponsor. 
14.4 
Safety Monitoring 
The Sponsor’s Medical Monitor and will monitor safety data throughout the course of the study. 
Renibus Drug Safety, or their designee, will expedite to the regulatory authorities only the 
suspected adverse reactions that are product-related and unexpected in accordance with FDA 21 
CFR 312, FDA draft guidance (Sept 2010) on Safety Reporting Requirements for INDs, and the 
ICH E2A guideline. 
14.5 
Quality Control and Quality Assurance 
By signing this protocol, the Sponsor agrees to be responsible for implementing and maintaining 
quality control and quality assurance systems with written standard operating procedures to 
ensure that the study is conducted and data are generated, documented, and reported in 
compliance with the protocol, accepted standards of GCPs, and all applicable federal, state, and 
local laws, rules and regulations relating to the conduct of the clinical study. 
By signing this protocol, the investigator agrees to conduct the study in an efficient and diligent 
manner and in conformance with this protocol, generally accepted standards of GCP, and all 
applicable federal, state, and local laws, rules and regulations relating to the conduct of the 
clinical study. 
The investigator also agrees to allow monitoring, audits, IRB review and regulatory agency 
inspection of study-related documents and procedures and provide for direct access to all study- 
related source data and documents. Investigators will be given notice before a quality assurance 
audit occurs. 
The investigator shall prepare and maintain complete and accurate study documentation in 
compliance with GCP standards and applicable federal, state, and local laws, rules and 

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regulations, and promptly submit to the Sponsor all forms and reports required by this protocol 
following completion or termination of the clinical study or as otherwise required due to any 
agreement with the Sponsor. 
 
15 GENERAL CONSIDERATIONS 
15.1 
Discontinuation of the Study 
The Sponsor reserves the right to discontinue this study or investigator’s participation in this 
study for safety or administrative reasons at any time. 

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16 AGREEMENT WITH PROTOCOL 
I have read this protocol and agree to conduct this clinical study as outlined herein. I will ensure 
that all sub-investigators and other study staff members have read and understand all aspects of 
this protocol. I agree to cooperate fully with Renibus Therapeutics, Inc. and its appointed 
Contract Research Organizations (CROs) during the study. I will adhere to all Food and Drug 
Administration (FDA), International Conference on Harmonisation (ICH), revised Declaration of 
Helsinki (2008) and other applicable regulations and guidelines regarding clinical trials on a 
study drug during and after study completion. 
Principal Investigator: 
 
 
 
  
 
 
 
  
 
 
 
  
 
Protocol REN-001A 
A Phase 1b dose-escalating study with RBT-1, in healthy volunteers and subjects with Stage 3-4 
Chronic Kidney Disease. 
Original Protocol: 
26 July 2019 (Revision 1) 
Revision 03:  
15 January 2020 
Printed Name: 
Signature: 
Date: 

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17 REFERENCES 
 
Anderson KE, Simionatto CS, Drummond GS, Kappas A. Disposition of tin-protoporphyrin 
and suppression of hyperbilirubinemia in humans. Clin Pharmacol Ther. 1986;39(5):510-20. 
Berglund L, Angelin B, Blomstrand R, Drummond G, Kappas A. Sn-protoporphyrin lowers 
serum bilirubin levels, decreases biliary bilirubin output, enhances biliary heme excretion and 
potently inhibits hepatic heme oxygenase activity in normal human subjects. Hepatology. 
1988;8(3):625-31. 
Berglund L, Angelin B, Hultcrantz R, et al. Studies with the heme oxygenase inhibitor 
Sn-protoporphyrin in subjects with primary biliary cirrhosis and idiopathic haemochromatosis. 
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Appendix 1 
Safety Clinical Chemistry, Hematology, and Urinalysis Tests Performed by 
the Laboratory at Screening, During the Study, and at Follow-up (EOS) 
 
Clinical Chemistry1 
Total protein 
Albumin 
Bicarbonate 
Blood urea nitrogen (BUN)6 
Creatinine5 
Total bilirubin 
Alkaline phosphatase 
Glucose 
Sodium 
Potassium 
Ferritin 
Transferrin saturation 
Inorganic phosphate 
Calcium (total and ionized) 
Magnesium 
Gamma-glutamyl transferase 
Alanine aminotransferase (ALT) 
Aspartate aminotransferase (AST) 
Cystatin-C 
Tin 
Tin Protoporphyrin 
IL-6 
Total Porphyrins7 
Hematology2 
Hemoglobin 
Hematocrit 
Erythrocyte count (red blood cells) 
Differential leukocytes 
Total leukocytes (white blood cells) 
Platelets 
Urinalysis3 
pH 
Specific gravity 
Glucose 
Ketones 
Bilirubin 
Urobilinogen 
Blood 
P21 
HO-1 
Hemopexin 
Ferritin 
Urine sediment 
Urine samples to test for RBT-1 response 
SnPP Urinary excretion4 
N acetyl-beta-D-glucosaminidase (NAG)7 
Kidney Injury Molecule-1 (KIM-1)7 
Neutrophil Gelatinase-Associated Lipocalin 
(NGAL)7 
Cystatin-C7 
Albuminuria 
Urine pregnancy test5 
Response Biomarkers6 
Haptoglobin 
Ferritin 
Hemopexin 
IL-10 
p21 
HO-1 
Bilirubin 
 
 
1 
Collect into serum separator tubes. 
2 
Collect into K2 EDTA tubes. 
3 
Approximately 10 mL of urine required for urinalysis including sediment. 
4 
Urinary excretion to be tested in a 24-hour volume sample 
5 
Urine dipstick: all women of childbearing potential prior to the first dose of RBT-1 on Study Day 1 and 
End of Study. Perform in the clinic using the pregnancy kit supplied by the laboratory. 
6 
Biomarkers run with standard Chemistry samples 
7 
Total Porphyrins, Cystatin-C, KIM-1, NGAL and NAG will only be assessed in Cohorts 1 through 7