A Randomized, Placebo-Controlled Study to Evaluate the Safety, Tolerability, and Physiological Effects on Liver Structure and Function of an Amino Acid Food Product, AXA1957, in Adolescent Subjects With Fatty Liver
Phase: NA
Conditions: NAFLD
Sponsor: Axcella Health, Inc

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Clinical Study Protocol 
Title 
A Randomized, Placebo-Controlled Study to Evaluate 
the Safety, Tolerability, and Physiological Effects on 
Liver Structure and Function of an Amino Acid Food 
Product, AXA1957, in Adolescent Subjects with Fatty 
Liver 
Protocol Number 
AXA1957-002 
Date (version) 
13-Dec-2019 – Version 3.0 
Sponsor Address 
Axcella Health Inc. 
840 Memorial Drive, 3rd Floor 
Cambridge, MA 02139 
 
 
 
 
 
 
 
CONFIDENTIAL 
This document contains confidential information.  Any use, distribution, or disclosure without the 
prior written consent of is strictly prohibited except to the extent required under applicable laws 
or regulations.  Persons to whom the information is disclosed must be informed that the 
information is confidential and may not be further disclosed by them. 
 
 

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INVESTIGATOR’S SIGNATURE OF AGREEMENT PAGE 
Protocol Title: A Randomized, Placebo-Controlled Study to Evaluate the Safety, Tolerability, and Physiological 
Effects on Liver Structure and Function of an Amino Acid Food Product, AXA1957, in Adolescent Subjects with 
Fatty Liver 
Protocol Number: AXA1957-002 
I, the undersigned, have reviewed this protocol, including appendices and I will conduct the study as described in 
compliance with this protocol, current Good Clinical Practice (GCP) guidelines and relevant International Conference 
on Harmonization (ICH) guidelines.  
Once the protocol has been approved by the Investigational Review Board (IRB)/Research Ethics Committee (REC), 
I will not modify this protocol without obtaining prior approval of Axcella Health (Sponsor) and of the IRB/REC. I 
will submit the protocol modifications and/or any informed consent form(s) (ICF) modifications to Axcella Health 
and the IRB/REC, and approval will be obtained before any modifications are implemented. except where necessary 
to eliminate an immediate hazard(s) to the study subjects. All personnel involved in the conduct of this study have 
completed Human Subjects Protection and ICH GCP Training. 
The protocol, ICF(s), recruitment materials, and all subject materials will be submitted to the IRB/REC for review and 
approval.  Approval of both the protocol and the consent form(s) must be obtained before any subject is enrolled.  Any 
amendment to the protocol will require review and approval by the IRB/REC before the changes are implemented to 
the study.  All changes to the consent form(s) will be IRB/REC approved; a determination will be made regarding 
whether a new consent needs to be obtained from subjects who provided consent, using a previously approved consent 
form(s). 
I understand that all information obtained during the conduct of the study regarding the subjects’ state of health will 
be regarded as confidential. No subjects’ names will be disclosed. All subjects will be identified by assigned numbers 
on all Case Report Forms (CFRs), laboratory samples or source documents forwarded to the Sponsor. Clinical 
information may be reviewed by the Sponsor or its agents or regulatory agencies. Agreement must be obtained from 
the subject before disclosure of subject information to a third party.  
Information developed in this clinical study may be disclosed by Axcella Health, to other clinical investigators, 
regulatory agencies, or other health authority or government agencies as required.  
Principal Investigator/Title (printed name):  
_________________________________________________________________________________________ 
 
Institution: ________________________________________________________________________________ 
 
Address: __________________________________________________________________________________ 
 
Telephone number: _________________________________________________________________________ 
 
Signature: _________________________________________________________________________________ 
Date: _____________________________________________________________________________________ 
 

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SPONSOR CONTACT INFORMATION 
Sponsor Responsible Person  
and Study Director: 
Margaret Koziel, MD 
840 Memorial Drive, 3rd floor,  
Cambridge, MA 02139 USA 
Telephone: +1 857 320 2238 
E-mail:mkoziel@axcellahealth.com 
 
 
 
Chief Investigator: 
Saul N. Faust, MBBS MRCPCH PhD FHEA 
Professor of Paediatric Immunology & Infectious 
Diseases, and Director NIHR Clinical Research Facility 
University of Southampton, 
C Level, West Wing, Mailpoint 218,  
University Hospital Southampton NHS Foundation 
Trust,  
Tremona Road, Southampton, SO16 6YD. 
  
Email: s.faust@soton.ac.uk 
 
 
 
 
 

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Table of Contents 
Study Synopsis ................................................................................................................................ 9 
Abbreviations ................................................................................................................................ 24 
1 
Introduction ....................................................................................................................... 26 
1.1 
Background and Rationale for the Proposed Study .......................................................... 26 
1.2 
Rationale for the Study Design and Amounts of Study Food Product Selected ............... 26 
2 
Objectives ......................................................................................................................... 36 
2.1 
Study Objective ................................................................................................................. 36 
2.2 
Study Assessments ............................................................................................................ 36 
3 
Investigational Plan ........................................................................................................... 37 
3.1 
Overall Study Design and Plan ......................................................................................... 37 
3.2 
Study Blinding .................................................................................................................. 38 
3.3 
Study Dietary and Physical Activity Requirements .......................................................... 38 
3.4 
Screening Period ............................................................................................................... 38 
3.4.1 Randomization .................................................................................................................. 39 
3.5 
Part 1: Mandatory Administration Period ......................................................................... 39 
3.5.1 Visit 1 / Day 1 and up to Week 1 ...................................................................................... 39 
3.5.2 Visit 2 (Week 1), Visit 3 (Week 3), Visit 4 (Week 7), Visit 5 (Week 10) & Visit 6 (Week 
13): 
39 
3.6 
Part 2: Optional Extension Period (12 weeks) .................................................................. 40 
3.6.1 Visit 6 (Week 13) Visit 7 (Week 15), Visit 8 (Week 19), Visit 9 (Week 22) & Visit 10 
(Week 25): .................................................................................................................................... 40 
3.7 
Follow-up Visit ................................................................................................................. 40 
3.8 
Early Discontinuation/Early Termination Visit ................................................................ 41 
4 
Selection of Study Population ........................................................................................... 41 
4.1 
Inclusion Criteria .............................................................................................................. 41 
4.2 
Exclusion Criteria ............................................................................................................. 43 
4.3 
Number of Subjects Planned ............................................................................................. 46 
4.4 
Removal of Subjects from the Study ................................................................................ 46 
5 
Study Food Product Information ...................................................................................... 47 
5.1 
AXA1957 Composition and Formulation Overview ........................................................ 47 

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5.2 
Placebo Composition and Formulation Overview ............................................................ 48 
5.3 
Study Food Product Preparation and Administration ....................................................... 48 
5.3.1 Modification of Study Food Product Administration Amount for Tolerability ............... 49 
5.3.2 Missed Study Food Product Administration ..................................................................... 49 
5.4 
Study Food Product Packaging, Labeling and Storage ..................................................... 49 
5.5 
Method of Assigning Study Food Product to Subjects ..................................................... 50 
5.6 
Accountability, Disposal, Return, or Retention of Unused Study Food Product ............. 50 
5.7 
Compliance with Study Food Product Administration ..................................................... 50 
6 
Concomitant Therapies and other restrictions .................................................................. 50 
6.1 
Concomitant Therapy........................................................................................................ 50 
6.1.1 Concomitant Use of the Following is Prohibited During the Study: ................................ 51 
7 
Study Assessments and Procedures .................................................................................. 52 
7.1 
Baseline and Disease Characteristics ................................................................................ 52 
7.2 
Physical Examination, Vital Signs and Body Weight ...................................................... 52 
7.3  
 12-Lead Electrocardiogram ............................................................................................. 52 
7.4 
Lifestyle Guidance ............................................................................................................ 53 
7.5 
Multiparametric MRI ........................................................................................................ 53 
7.6 
Fibroscan or Right Upper Quadrant Ultrasound Assessment ........................................... 53 
7.7 
Clinical Laboratory Assessments ...................................................................................... 53 
7.8 
Plasma Amino Acid Concentration Sampling .................................................................. 57 
7.9 
Food and Activity Diaries & Dietary Guidance ............................................................... 57 
7.9.1 Study Dietary and Exercise Guidance .............................................................................. 57 
7.9.2 Four Day Diet and Exercise Diary .................................................................................... 57 
7.9.3 National Institute for Health and Care Excellence Quality Standard Life Style Questions
 
57 
7.10 
Hunger and Satiety Visual Analog Scale (VAS) .............................................................. 58 
7.11 
Study Food Product Administration Diary ....................................................................... 58 
8 
Adverse Events and Safety Reporting .............................................................................. 59 
8.1 
Definitions......................................................................................................................... 59 
8.1.1 Adverse Events ................................................................................................................. 59 
8.1.2 Adverse Reaction and Suspected Adverse Reaction ........................................................ 59 

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8.1.3 Serious Adverse Event Definition .................................................................................... 59 
8.1.4 Causal Relationship Assessment....................................................................................... 60 
8.2 
Categorization of Adverse Events .................................................................................... 60 
8.3 
Recording and Reporting of All Non-Serious and Serious Adverse Events .................... 61 
8.4 
Serious Adverse Event Reporting Procedures .................................................................. 61 
8.4.1 Safety/SAE Reporting Contact Information ..................................................................... 62 
8.5 
Data and Safety Monitoring Committee ........................................................................... 62 
8.6 
Reporting to IRBs and Ethics Committees ....................................................................... 63 
8.7 
Contraception and Pregnancy ........................................................................................... 63 
9 
Statistical Analysis ............................................................................................................ 64 
9.1 
Sample Size ....................................................................................................................... 64 
9.2 
Analysis Sets ..................................................................................................................... 64 
9.2.1 Safety Analyses ................................................................................................................. 64 
9.3 
Interim Analysis ................................................................................................................ 65 
9.4 
Pharmacokinetics .............................................................................................................. 65 
10 
Ethics and Administrative Details .................................................................................... 66 
10.1 
Ethics................................................................................................................................. 66 
10.2 
Informed Consent/Patient Information Sheet ................................................................... 67 
10.3 
Administrative Details ...................................................................................................... 67 
10.3.1 Monitoring ........................................................................................................................ 67 
10.3.2 Recording, Access and Retention of Source Data ............................................................ 68 
10.3.3 Study Termination ............................................................................................................ 68 
10.3.4 Protocol Violations ........................................................................................................... 68 
10.3.5 Data Quality Assurance .................................................................................................... 69 
10.3.6 Case Report Form ............................................................................................................. 69 
10.3.7 Publication ........................................................................................................................ 69 
11 
References ......................................................................................................................... 70 
 
 
 
 

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TABLES 
Table 1. Schedule of Assessments Table ...................................................................................... 21 
Table 2. Amounts of AXA1957 Components Present in Diet ...................................................... 27 
Table 3. Summary of Studies Supporting the Administration of the Components within the 
AXA1957 Food Product ............................................................................................................... 29 
Table 4. Summary of Adverse Events in Study AXA1125-003 in the Safety Population (observed 
as of 15 October 2019; reported in 2 or more subjects) ................................................................ 34 
Table 5. Interim Analysis of the Effects of AXA1957 on Metabolism and Organ Structure and 
Function from Study 1125-003 (Week 16) ................................................................................... 35 
Table 6. Amino Acid Composition of AXA1957 per Stick Pack ................................................. 47 
Table 7. Excipient Composition of AXA1957 ............................................................................. 48 
Table 8. Laboratory Assessments ................................................................................................. 55 
 
FIGURES 
Figure 1. Study Schematic ............................................................................................................ 37 
Figure 2: Timing of Visual Analog Scale Completion ................................................................. 58 
 
APPENDICES 
Appendix 1 Guidance and Lifestyle Recommendations for Adolescents with NAFLD .............. 75 
 
 
 

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Study Synopsis 
Protocol Number 
AXA1957-002 
Protocol Title  
A Randomized, Placebo-Controlled Study to Evaluate the Safety, 
Tolerability, and Physiological Effects on Liver Structure and Function of 
an Amino Acid Food Product, AXA1957, in Adolescent Subjects with 
Fatty Liver. 
Study Objectives 
To assess the safety, tolerability, and parameters of liver health in 
adolescent subjects with fatty liver when administered AXA1957, an amino 
acid food product.  
Study Assessments  Safety and tolerability will be assessed by: 
x Reported clinical adverse events (AEs) 
x Physical examinations, including changes in body weight and 
body composition such as lean mass and fat mass 
x Vital sign assessments 
x Electrocardiograms (ECGs) 
x Clinical laboratory tests including changes in standard 
haematology, chemistry, and lipid panels  
Liver structure and function will be assessed by: 
x Multiparametric magnetic resonance imaging (MRI) assessments 
of liver structure (fat content and inflammation changes) 
x Blood tests of liver function, including markers of inflammation 
and fibrosis  
Number of Study 
Sites 
Up to 7 sites in the UK and US 
Study Population 
Male and female subjects between 12 and 17 years of age, inclusive.   
Number of 
Subjects 
Sufficient number of subjects will be screened to have approximately 30 
subjects complete the study. 
Note: Subjects withdrawing early in Part 1 may be replaced. Subjects will 
not be replaced in Part 2. 
 
 

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Summary of Study 
Design 
 
This is a randomized, placebo-controlled study conducted in 2 Parts: a 
mandatory 13-wk administration period (Part 1) and an optional extension 
period up to a maximum of 12 additional weeks (Part 2); see Figure 1 
below.   
Figure 1: Study Schematic 
 
The total duration of the study from Screening to the end of Part 2 follow-
up is anticipated to be approximately 31 weeks. It is anticipated that there 
may be a total of approximately up to 12 study visits during the entire study 
(Screening, Parts 1 and 2).  
In Part 1, following up to a 4-week screening period, eligible subjects will 
be randomized in a 2:1 ratio to receive either AXA1957 or placebo for a 
13-week administration period.  
Subjects will be centrally randomized with gender (male/female) as the 
stratification factor to AXA1957 or placebo groups. Randomization will 
occur via an interactive web response system (IWRS) after eligibility is 
confirmed and prior to the Day 1 Visit. Study food product amounts will be 
gradually escalated through the first week of study participation to assess 
tolerability issues to the food product during the initial week, and to enable 
subjects and their caregivers to get accustomed to the twice daily regimen. 
Safety and tolerability will be monitored throughout the study.  
All subjects will be provided diet and physical activity recommendations 
consistent with Guidance and Lifestyle Recommendations for Adolescents 
with NAFLD; see Appendix 1.  
Following the mandatory Part 1 period, all subjects including those 
randomized to the placebo-arm in Part 1, will have an option to continue in 
the study in Part 2 for up to an additional maximum of 12 weeks on the 
AXA1957 food product. All subjects who opt to enter Part 2 will be 
administered AXA1957 at the same amount and regimen as in Part 1 (i.e. 
up to 2 stick packs twice daily starting from Week 14) and will continue to 
be provided the standard lifestyle guidance.  Subjects who choose not to 
participate in Part 2, will undergo a safety follow up visit approximately 2-
weeks after Visit 6 per the procedures in Schedule of Assessments (SOA) 
Extension participants
AXA1957 ( 12 weeks)
Placebo (1+12 weeks)
MRI
PART 1 
Mandatory AXA1957 or 
Placebo Administration Period (13 weeks)
W1
R
W3
W10
W7     
MRI
AXA1957 (1+12 weeks)
PART 2 
Optional AXA1957 Extension 
Period (up to a maximum of 12 weeks)
MRI
W15
W13
W25
W27
Screening  Period
( 4 weeks)
Follow-up
(2 weeks)
Follow up
2 wks
Includes a 4-day period to 
collect  baseline 
diet/physical activity 
pattern, and screening MRI 
IA #2 
50%
n=20
n=10
MRI
IA #1 
50%
W19
W22
PK
PK
D1

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Table 1. There will be a 2-week follow up period after subjects complete 
Part 2.   
If subjects drop out at any time for any reason during either Part 1 or 2 of 
the study, including the follow up period, their last visit should capture all 
the assessments as the end-of-study assessments as shown in Table 1.   
Screening Period: Once written informed consent/assent is obtained, 
screening procedures will be completed per the SOA in Table 1. Screening 
period may be up to 4 weeks before starting Part 1. During this period, 
subjects will be asked to complete a diet and exercise diary over  4 days, 
which should include two weekdays and 2 weekend days. Subjects will 
record to the best of their ability all the typical foods/beverages they 
eat/drink on those days, and their usual physical activity routines to 
establish a baseline lifestyle pattern. During the entire screening period 
subjects should continue their normal habitual diet, physical activity 
patterns and routines (e.g., school, extracurricular activities, including their 
usual sports activities), and their prescribed standard of care therapies, if 
applicable.  
Subjects are also be required to undergo a screening multiparametric MRI 
scan within approximately 7 days before potential randomization. Subjects 
will be instructed to fast for at least 4-hours prior to their scheduled MRI; 
subjects will have to meet the screening MRI criteria to be eligible for 
randomization.    
Subjects who screen fail due to ALT may be re-screened one time. 
PART 1: MANDATORY ADMINISTRATION PERIOD (13 WEEKS)  
Visit 1 / Day 1 and up to Week 1:  
Eligible subjects will be randomized via the IWRS and will receive either 
placebo or AXA1957 with instructions (to both subjects and their 
caregivers) on how to prepare and consume the study food product, 
including timing of administration.  
On Day 1, subjects will arrive to the study site following an overnight fast 
of approximately 8 hours. Prior to study food product administration, 
subjects will undergo fasting blood draws and other assessments per the 
SOA in Table 1. The first administration of the study food product will be 
at the study site supervised by the study staff. After the study food product 
administration, subjects will have one additional blood draw for plasma 
amino acid concentration approximately 1-2 hours after the study food 
product administration and then discharged from the study site.   
During the Day 1 visit, all subjects will be provided Guidance and Lifestyle 
Recommendations for Adolescents with NAFLD (See Appendix 1).  
Qualified site staff will explain these recommendations and answer any 
questions the study participant and/or their family may have.   

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During the first week of study food product administration in both 
AXA1957 and placebo groups, subjects will follow the administration 
schedule below: 
- 
Days 1 to 3: 1 stick pack twice daily (total of 2 stick packs daily) 
- 
Days 4 through the remainder of the study: 2 stick packs twice daily 
(total of 4 stick packs daily) 
Twice daily regimen of the food product should occur within 30 minutes 
(i.e. 30 ±5 minutes) before meals (e.g., before breakfast and dinner or 
before lunch and dinner, if breakfast is not a usual part of their daily 
routine).  Any adjustments to this regimen or amount may be considered on 
a case-by-case basis (see additional details under Study Food Product 
Section below).   
Site staff will conduct a phone call on Day 3 to assess tolerability, and if 
tolerated, remind the subject to increase the food product to 2 stick packs 
twice a day (4 stick packs daily) for the remainder of the study 
administration period. 
 
Visit 2 (Week 1) to Visit 6 (Week 13): 
All procedures during Visits 2 through 6 will be performed per the SOA in 
Table 1. 
Subjects will be asked to bring all their study food product stick packs (full 
and empty) to each clinic visit for site staff to perform accountability. 
Subjects are also required to bring their study food product administration 
and lifestyle diaries for review at each clinic visit.  
During weeks where there are no clinic visits, qualified study staff will 
make approximately weekly phone calls to subjects to ensure compliance 
with the study food product administration/regimen, answer any questions, 
and check-in with subjects/caregivers. 
 
PART 2: Optional Extension Period (12 Weeks) For All Subjects 
Visit 6 (Week 13) to Visit 10 (Week 25):    
After the completion of the mandatory 13-week period (Visit 6), all 
subjects from Part 1 have the option to enter Part 2 where subjects 
(including those that received placebo in Part 1) will receive up to a 
maximum of 12 additional weeks of AXA1957 food product.   
The determination of whether to continue in the optional period is based 
upon the following:  
x The subject is willing and able to participate in the study for up to 
12 additional weeks, and  
x There are no negative signals as determined by the clinical 

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judgement of the study medical monitor, investigator, dietician, 
and/or Sponsor after carefully considering safety, tolerability, 
health status, body weight, body composition, MRI, and/or blood 
parameters. 
Subjects who do not participate in Part 2 will undergo an end-of-study 
follow up visit approximately 2-weeks after Visit 6 per procedures in the 
SOA in Table 1. 
Subjects who participate in Part 2 will be provided a supply of AXA1957 
study food product at Visit 6 and will be instructed to start consuming 2 
stick packs twice daily (4 stick packs daily). 
There will be at least 4 study visits in Part 2, and all procedures during those 
visits will be performed per the SOA in Table 1. Safety and tolerability of 
the study food product will continue to be assessed as was in Part 1.  
If subjects drop out at any time for any reason during the  study, their last 
visit should capture all the assessments as the end-of-study assessments as 
shown in Table 1.  Subjects will not be replaced in Part 2. 
Follow up Visit  
Subjects who participate in Part 1 only will return to the study site for a 
follow-up visit approximately 2 weeks after Visit 6 and will follow the SOA 
procedures per Table 1.  
Subjects who opt to participate in Part 2 will return to the study site for 
follow-up visit approximately 2 weeks after Visit 10 and will follow the 
SOA procedures per Table 1. 
Early Termination Visit 
Subjects who discontinue the study early for any reason are expected to 
complete the Early Termination Visit and will follow the SOA procedures 
per Table 1. 
Study Dietary and 
Physical Activity 
Requirements 
 
During each study visit, subjects will meet with a study dietician or other 
qualified study staff who will reinforce the lifestyle recommendations in 
Appendix 1 to subjects and their caregivers. In between the study visits, 
subjects may receive phone calls approximately once a week where 
qualified study staff may continue to reinforce these lifestyle 
recommendations.    
Study Food 
Products   
 
AXA1957 is composed of naturally occurring amino acids, which are 
normal ingredients of food or those readily available as dietary 
supplements.   
The placebo is a balanced food product formulated as a dry powder that 
will be reconstituted with ~6 oz (~180 mL) of water to form an orange 
flavored drink that is color, taste, and calorie matched to AXA1957.   

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Study food products are provided in dry powder form in stick packs, which 
are then mixed in ~6 oz (~180 mL) of water, and then consumed twice daily 
approximately 30 min (i.e., 30 ±5 minutes) before meals (e.g., before 
breakfast and dinner or before lunch and dinner, if breakfast is not a usual 
part of their daily routine) for the entire duration of the study.   
Note: While subjects are encouraged to consume the study food product at 
defined times as indicated above to establish a clear routine which improves 
adherence to study procedures, it is more important in this study to 
ensure that subjects consume their assigned products twice a day.  To 
that end, the following flexibility is allowed within the administration 
periods: 
x The twice daily (BID) administrations can occur at any time 
during the day if the two administrations are at least 4 hours apart, 
and the study food products are not consumed immediately before, 
with, or immediately after a main meal.   
x If subjects experience any clinically significant gastrointestinal 
(GI) discomfort while taking their study food product prior to 
meals, administrations may occur approximately 30-60 minutes 
after the meal, and only after consulting with the investigator, and 
Medical Monitor or Sponsor.  
x Every attempt should be made to encourage subjects to stay on 
their assigned amount and regimen for the full duration of the 
study. However, if the study investigator determines any 
tolerability issues of clinical significance, the amount of AXA1957 
or placebo may be reduced for an individual subject to an amount 
and/or regimen that was previously tolerated, but only after 
discussion with the Medical Monitor or Sponsor. For instance:  
o If the 2-stick pack  twice daily  amount is not tolerated, 
then the amount for that individual subject may be reduced 
to 1 stick pack  twice daily ; 
o Any subject who is not able to tolerate the study food 
product or placebo at any amount (e.g., even at 1 stick pack  
twice daily) should be discontinued from the study and 
undergo the End-of Study visit procedures.  
 
Compliance check-in and accountability review with both the study food 
product and lifestyle recommendations will be performed by study staff at 
every visit during both Parts 1 and 2. 
Inclusion Criteria  
Subjects must meet all the following criteria to be eligible to participate in 
the study: 
1. Male and female adolescent subjects between 12 and 17 years of 
age, inclusive.   
2. Female subjects must be at least 2-years post-menarche as 
determined by clinical history.  

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3. Willing and able to provide written informed consent from 
parent(s) or legal guardian, as required. 
4. Willing and able to provide written assent from subject, as 
required. 
5. Stated willingness and ability of parent/guardian and the subject to 
take the study food product twice a day and adhere with all study 
procedures and requirements.  
6. Body weight ≥ 60 kg at time of screening and subjects should be 
within ±5% of their body weight over the last 30 days prior to 
Screening. 
7. Subjects should be at risk for fatty liver, which may be assessed by 
any one (1) of the following: 
a.  Historical liver biopsy that was obtained up to 6 months prior 
to Screening (local pathology interpretation may be used) with 
Steatosis greater than Grade 1, if applicable as part of standard 
of care. 
Note: For the historical liver biopsy to satisfy the fatty liver 
requirement, the biopsy must have been obtained with no 
NAFLD or NASH treatment, medications that can cause 
steatosis 
or 
NASH, 
or 
other 
interventional 
agents/procedures for the treatment of NAFLD/NASH 
within 3 months prior to when the liver biopsy was obtained;  
OR                                                
b. Fasting ALT ≥ 50 U/L in boys, ≥45 U/L in girls, and ≤ 150 
U/L in both genders at the Screening visit labs; OR  
c. Fibroscan with Control Attenuation Parameter (CAP) ≥ 280 
dB/m within 90 days of Randomization; OR  
d. Any of the following right upper quadrant (RUQ) ultrasound 
sonographic features suggestive of hepatic steatosis within 90 
days of Randomization, for e.g.: liver uniformly 
heterogeneous; echogenic diffusely with bright hepatic echoes 
within the first 2-3 cm of depth with increased hepatorenal 
echogenicity (i.e., liver with areas of significantly increased 
echogenicity relative to the renal parenchyma); attenuation of 
image quickly within 4-5 cm of depth making deeper 
structures difficult to decipher; thick subcutaneous depth (> 2 
cm);  vascular blurring of portal or hepatic vein.   
  
8. MRI Proton Density Fat Fraction (PDFF) >10%  and corrected T1 
(cT1) > 820 msec using multiparametric MR imaging of the liver.    
Note: Screening MRI should occur approximately within 7 
days prior to randomization and must NOT occur until each 
of the above entry criteria #1 through #7 have been 
confirmed.   

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9. Subjects may have  either prediabetes or type 2 diabetes (T2DM). 
Prediabetes is established by one of the following: 
a. Fasting Blood Glucose is ≥100 mg/dL (5.5 mmol/L) but 
<126 mg/dL (7.0 mmol/L) or HbA1c ≥5.7% but <6.4% 
based on the Screening visit labs;  
OR 
b. Historical evidence (i.e. within 3 months of 
Randomization) of impaired fasting glucose/glucose 
intolerance per the standard of care guidelines and usual 
procedures of the study center;  
OR 
c. Subject is already on a stable regimen for approximately 60 
days prior to Randomization  for the treatment of 
prediabetes (e.g., diet/lifestyle, metformin, etc.).   
10. Subjects with Investigator-confirmed T2DM should have HbA1c 
≤9.5% at Screening and must be stable on their usual diabetic 
medications for approximately 60 days prior to Randomization 
and should not be anticipating clinically significant dose 
adjustments of the T2DM medications for the anticipated duration 
of the study. 
11. Subjects taking vitamins and/or other dietary/herbal supplements 
are permitted as long as ALL the following are met: 
a. Vitamin(s) or other supplement(s) are not on the list of 
prohibited medications (see Section 6.1.1), and  
b. Subject has been on stable doses and regimens for at least 2 
months prior to Randomization; however, if vitamin E is at 
doses ≥400 IU/day, it must be discontinued prior to 
Randomization if subject otherwise qualifies into study, and  
c. There are no anticipated dose adjustments or changes (i.e. 
stopping or adding) of vitamins/supplements for the duration 
of the entire study, including the optional extension period. 
12.  Heterosexually active female participants of childbearing 
potential (i.e. post-pubertal and /or post-menarchal, not surgically 
sterile [defined as tubal ligation, hysterectomy, or bilateral 
oophorectomy]) must agree to abstain from sexual intercourse for the 
entire duration of the study (i.e., from time ICF is signed to end-of-
study follow up) as any hormone-based contraception approaches are 
not allowed in the study (e.g., oral contraceptive pills are excluded 
medications for this study), and barrier approaches (e.g., condom with 
spermicide, diaphragm with spermicide) alone are not considered 
adequate to prevent pregnancy. Sexual activity will be ascertained at 
each study visit, and every female participant in the study must 
complete a required pregnancy test at each study visit.  
 
Exclusion Criteria 
Subjects are not eligible to participate in the study if any of the following 
criteria are met:  

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1. History of any acute or chronic liver disease, other than non-
alcoholic fatty liver disease, such as drug-induced, autoimmune, or 
any viral hepatitis, hemochromatosis, Wilson’s, primary sclerosing 
cholangitis.  Clinical / medical  history or appropriate laboratory 
/serological assessments, if necessary, may be relied upon to rule 
out these other causes of liver disease.   
2. Known positive for human immunodeficiency virus (HIV)  
3. Presence of Stage 4 fibrosis in the liver 
4. Non-compensated liver disease with any one of the following 
hematologic, biochemical, and serological criteria at Screening: 
a. Hemoglobin < 10 g/dL 
b. White blood cell < 3,500 cells/mm 
c. Neutrophil count < 1,500 cells/mm3 of blood 
d. Platelets < 130,000 cells/mm3 of blood 
e. Direct bilirubin > 1.0 mg/dL (>17.1 Pmol/L) 
f. Total bilirubin ≥ 3 mg/dL (≥51.3 Pmol/L, unless Gilbert’s 
Syndrome).  However, subjects with Gilbert’s syndrome 
with direct bilirubin above upper limits of normal (ULN) in 
addition to total bilirubin ≥ 3 mg/dL (≥51.3 Pmol/L), or 
with evidence of hemolysis contributing to elevated total 
bilirubin, should be excluded. 
g. Albumin < 3.2 g/dL (<48.1 Pmol/L)  
h. International normalized ratio (INR) > 1.4 
5. Any active/clinically unstable GI (e.g., motility disorders, celiac 
disease, malabsorption syndromes), cardiovascular (e.g., 
hypertension and hyperlipidemia requiring pharmacologic 
treatment), endocrine (e.g., Cushing’s syndrome congenital 
adrenal hyperplasia, polyglandular endocrinopathies, 
hypo/hyperthyroidism requiring pharmacologic treatment, 
genetic/secondary causes of obesity), flaring autoimmune diseases 
(juvenile idiopathic arthritis, adolescent lupus, juvenile 
dermatomyositis) or psychiatric conditions (clinically significant 
depression, ADHD, psychosis). 
Note 1: Subjects with asthma may be enrolled at the 
discretion of the Investigator if their condition is stable (i.e. 
no exacerbations within 4-6 weeks prior to Randomization 
and no clinically meaningful changes in their asthma 
management regimens are anticipated for the duration of the 
study). 
Note 2: Subjects who are on a stable dose of anti-depressant 
medication(s) or medication(s) for ADHD for at least 6 
months prior to Randomization and whose Investigator 
considers them to be psychiatrically stable may be enrolled.  
6. Known history of Inborn Errors of Metabolism and/or genetic 
deficiencies that impact amino acid metabolism or transport [e.g., 
urea cycle disorders, carnitine deficiency, carnitine palmitoyl 

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transferase (CPT) I or II deficiency, beta-oxidation defects, 
pyruvate carboxylase deficiency, porphyria, etc.] 
7. Current acute illness/health condition requiring ongoing medical 
treatment. Subjects with minor illness/injury that the investigator 
considers unlikely to significantly impact study participation or 
study assessments/endpoints should be discussed with the study 
Medical Monitor and/or Sponsor to determine whether the subject 
may be included, if all other eligibility criteria are met. 
8. Any form of diabetes other than T2DM (e.g., Type 1, MODY). 
9. Uncontrolled T2DM, which is defined as:  
a. HbA1c >9.5 % on their current T2DM regimen at 
Screening and must be stable on their usual diabetic 
medications for approximately 60 days prior to 
Randomization and should not be anticipating clinically 
significant dose adjustments of the T2DM medications for 
the anticipated duration of the study, and/or   
b. Requiring >10% insulin dose adjustments within 60 days 
prior to Randomization, and/or 
c. Requiring a complex medical regimen, e.g., needing 2 or 
more oral anti-diabetics (OAD)s, and/or with a history of 
severe hypoglycemia on their OAD regimens. 
10. Uncontrolled hypertension (i.e. systolic blood pressure >130 
mmHg and/or diastolic blood pressure >80 mmHg) at Screening. 
11. Uncontrolled hyperlipidemia (i.e., triglycerides >350 mg/dL 
and/or low-density lipoprotein (LDL) >160 mg/dL) at Screening. 
12. Impaired renal function (i.e., glomerular filtration rate ≤ 90 
mL/min/1.73 m2) at Screening.  
13. History of bariatric surgery or planning to undergo bariatric 
surgery during the study duration (including Part 2). However, 
prior laparoscopic-band, intra-gastric balloon, or other weight loss 
device which was removed >12 months prior to Screening is not 
exclusionary. 
14. Any contraindications to an MRI scan, including: 
a. Presence of non-removable ferromagnetic implants, 
pacemakers, aneurysm clips or other foreign bodies, or 
b. Unable to have or complete the MRI exam due to body 
weight exceeding scanner table limit or girth exceeding 
scanner bore diameter, or 
c. Clinically significant claustrophobia. Subjects experiencing 
mild anxiety due to transient claustrophobic symptoms 
may be treated with anxiolytics, if appropriate and per 
study site SOPs, for mitigation of those symptoms, if 
necessary. 
15. Known sensitivity and/or clinically significant food 
intolerance/allergies to proteins (such as whey, soy, casein, 
collagen, gelatin, amino acids, etc.), gluten, fats, carbohydrates 

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(e.g., lactose), nuts or any ingredient in the study food product 
formulations. 
16. History of total parenteral nutrition (TPN) 6 months prior to 
Screening. 
17. Current or planned use of any dietary supplement intended for 
general metabolic health, weight maintenance, weight loss, OR 
those containing proteins, amino acids, ketones, or fish oils, from 
the time the ICF is signed through the end of the study.   
Note: Common examples of excluded protein, amino acid, 
and other dietary supplements include, but are not limited 
to: ketones, protein powders, shakes, bars, gels containing 
whey, soy, casein, collagen, amino acids, and their 
derivatives/metabolites, N-acetylcysteine, L-carnitine, etc. 
A few examples of supplements used for weight loss include 
green tea, green coffee bean extracts, garcinia cambogia, 
any ketogenic products, etc.  
18. Currently on or planning to be on any extreme or unbalanced diet 
such as Ketogenic, Atkins, Paleo, etc.) from the time the ICF is 
signed through the end of the study. 
19. Use within 2 months prior to or during Screening, or during the 
study, of systemic glucocorticoids, any biologics (e.g., monoclonal 
antibodies),  hormones of any kind (e.g., estrogens, progesterone, 
testosterone), valproic acid, ursodeoxycholic acid, any anti-obesity 
compounds (e.g., orlistat, locaserin, Qsymia), GLP-1 agonists, 
TZDs, or any other medications known to cause hepatic steatosis, 
or steatohepatitis, or use of any other known or potential 
hepatotoxins.  
20. Use of any other excluded medications listed in Section 6.1.1 of 
the protocol not otherwise specified in the entry criteria.    
21. Use of any illicit substances, including alcohol, and nicotine 
products 
22. If female, ongoing pregnancy (defined as positive serum and/or 
urine pregnancy test), and/or planned pregnancy, breast-feeding. 
23. Male subjects with female partners of child-bearing potential who 
are unwilling or unable to adhere to contraception requirements. 
24. History of any malignancy, other than nonmelanoma skin cancer, 
within 4 years prior to Screening. 
25. Subjects who are currently enrolled in a clinical trial or who 
received an investigational study drug/medication, or any dietary 
supplement(s), food product(s), or participated in a lifestyle / 
nutritional interventional study/program within 60 days prior to 
Screening.  
26. Any other condition that, in the opinion of the investigator, renders 
or places the subject  at risk for inclusion in the study, or that 
would impede compliance, or hinder completion of the study.  

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Statistical Methods All analyses will be performed, and all tables, figures, and data listings will 
be prepared using SAS version 9.4 or higher.  Summary statistics for 
continuous variables will include the mean, standard deviation, median, 
minimum and maximum value; categorical variables will be presented as 
counts and percentages.  Some subgroup analyses (such as liver fat or ALT 
assessments) may be performed within each of the gender groups given the 
known and well-established gender differences in these parameters. 
  
Safety and tolerability will be evaluated using descriptive statistics and 
listings of AEs, physical examination, including body composition (lean 
and visceral fat mass) changes, clinical laboratory test values, including 
plasma amino acid levels, vital signs, weight, body temperature, ECGs and 
other safety parameters. Analyses of AEs will be performed for those events 
that are considered study food product-emergent, where study food 
product-emergent is defined as any AE with onset (or worsening of a pre-
existing condition) after the first administration of the study food product.  
 
Interim analyses in addition to the final analysis are planned for this study. 
Up to two interim analyses are planned in Part 1: one after approximately 
50% of subjects complete Visit 4 (Week 7), and another after approximately 
50% of subjects complete Visit 6 (Week 13).  
 
Subjects will be centrally randomized into AXA and Placebo with a block 
size of 3, stratified by gender through an IWRS system. 

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Table 1. Schedule of Assessments Table 
Study Period 
Screening 
Period 
  
PART 1 
Mandatory AXA1957 or Placebo Administration Period 
 (13 weeks) 
 
PART 217 
Optional AXA1957 Extension Period 
(up to a maximum of 12 weeks) 
Follow-
up Period  
(2 weeks) 
Early 
Term1 
  
Up to 
28 days 
prior to 
Day 1 
Visit 
1  
Day 1 
  
Visit 2  
Wk 1 
(+3 
days) 
Visit 3 
Wk 3 
(+/- 5 
days) 
Visit 4  
Wk 7 
(+/- 5 
days) 
Visit 5  
Wk 10 
(+/- 5 
days) 
Visit 6 
Wk 13 
(+/- 5 
days) 
Visit 714 
Wk 15 
(+/-5 
days) 
Visit 8 
Wk 19 
(+/- 5 
days) 
Visit 9  
Wk 22 
(+/-5 
days) 
Visit 10  
Wk 25 
(+/- 5 
days) 
Visit 11 
Wk 27 
(+/-3 
days) 
 
Informed consent/Assent 
X 
 
 
 
 
 
 
 
 
 
 
 
 
Confirm eligibility 
X 
X 
 
 
 
 
 
 
 
 
 
 
 
Randomization16 
 
X 
 
 
 
 
 
 
 
 
 
 
 
Demographics and 
Medical History 
X 
 
 
 
 
 
 
 
 
 
 
 
 
Con. Medications 
X 
X 
    X 
X 
X 
   X 
  X 
X 
X 
X 
X 
X 
X 
Physical examination2 
X 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Height, weight and waist 
circumference 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Vital signs3 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Pregnancy test4 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
ECG 
X 
 
 
 
 
 
X 
 
 
 
X 
 
X 
MRI Scan5 
X 
 
 
 
X 
 
X 
 
 
 
X 
 
 
Fibroscan or RUQ 
ultrasound 
X 
 
 
 
 
 
 
 
 
 
 
 
 
Serum chemistry11 
X 
X 
 
 
X 
 
X 
 
X 
 
X 
X 
X 
Haematology/coagulation 
X 
X 
 
 
X 
 
X 
 
X 
 
X 
X 
X 
HbA1c11 
X 
X 
 
 
X 
 
X 
 
 
 
X 
 
X 
Blood samples for 
metabolic, inflammation 
and fibrosis biomarkers 
7,11 
 
X 
 
 
X 
 
 
X 
 
X 
 
X 
 
X 
Fasting lipid profile11 
X 
X 
 
 
 
 
X 
 
 
 
X 
 
X 
OWL lipidomic profile11 
 
X 
 
 
 
 
X 
 
 
 
X 
 
X 
Blood sample for PBMC 
isolation6,11 
 
X 
 
 
 
 
X 
 
 
 
X 
 
 

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Study Period 
Screening 
Period 
  
PART 1 
Mandatory AXA1957 or Placebo Administration Period 
 (13 weeks) 
 
PART 217 
Optional AXA1957 Extension Period 
(up to a maximum of 12 weeks) 
Follow-
up Period  
(2 weeks) 
Early 
Term1 
  
Up to 
28 days 
prior to 
Day 1 
Visit 
1  
Day 1 
  
Visit 2  
Wk 1 
(+3 
days) 
Visit 3 
Wk 3 
(+/- 5 
days) 
Visit 4  
Wk 7 
(+/- 5 
days) 
Visit 5  
Wk 10 
(+/- 5 
days) 
Visit 6 
Wk 13 
(+/- 5 
days) 
Visit 7 
Wk 15 
(+/-5 
days) 
Visit 8 
Wk 19 
(+/- 5 
days) 
Visit 9  
Wk 22 
(+/-5 
days) 
Visit 10  
Wk 25 
(+/- 5 
days) 
Follow-
Up14 
 (+/-3 
days) 
 
Blood sample for amino 
acid concentrations12 
 
X 
 
 
 
 
X 
 
 
 
X 
 
X 
Urinalysis (quantitative) 
X 
X 
 
 
 
 
X 
 
 
 
X 
 
X 
Lifestyle guidance & 
monitoring 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
4-day baseline diet and 
exercise diary15 
X 
 
 
 
 
 
 
 
 
 
 
 
 
Diet/Exercise lifestyle 
Questionnaire10 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Study food product 
administration diary8 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
VAS9 
 
X 
 
 
X 
X 
X 
X 
X 
X 
X 
X 
 
 
Dispense Study Food 
Product13 
 
X 
 
X 
X 
X 
X13 
X 
X 
X 
 
 
 
Study food product 
accountability 
 
X 
 
X 
X 
X 
 
X 
 
X 
X 
X 
X 
X 
 
X 
Record adverse events  
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Assess eligibility and 
willingness of subject to 
participate in Part 2 
 
 
 
 
 
 
 
X 
 
 
 
 
 
 
Weekly Phone Calls8  
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
 
 

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Schedule of Assessment Footnotes 
1Subjects who discontinue early in Part 1 or Part 2 will be asked to complete all assessments as indicated.  Subjects who discontinue early and who have had the multiparametric MRI scan within 1 week 
of the date of discontinuation will not be required to repeat the early termination MRI. 
2PE will consist of an assessment of general appearance, skin, thorax/lungs, abdomen, lymph nodes, head, ears, eyes, nose, throat, neck, cardiovascular, musculoskeletal, and neurological systems.   
3Vital signs include sitting systolic and diastolic blood pressure, heart rate, respirations and temperature.  Blood pressure should be obtained after the subject has been sitting calmly for at least 5 minutes   
4Serum pregnancy test at Screening visit and urine pregnancy test on all other visits.  
5The screening MRI scan should occur approximately within 7 days prior to randomization and must NOT occur until each of the inclusion criteria #1 through #7 have been confirmed.    Subjects are 
required to be fasting for at least 4 hours prior to all MRI scans.  Scans should be scheduled based on scanner availability which may not correlate with the same day as the study clinic visit.  MRIs at 
Visit 7 and 13 are not required to occur the same day as the study clinic visit, but must occur within the +/- 5 day visit window. Every attempt should be made to schedule scans at roughly the same time 
of the day to reduce diurnal fluctuation in daily liver lipid levels. 
6PBMC isolation required on Day 1 and Day W13 and Week 25 (extension period). 
7See Table 8– Clinical Laboratory Evaluations for a list of biomarkers to be collected at the indicated time points. A retain sample of plasma will be collected at each biomarker timepoint for possible 
future non-genetic exploratory analysis.   
8The study dietician (or other qualified staff) will confirm that subjects are administering their assigned study food product accurately, and answer any questions on usual Lifestyle Recommendations for 
Adolescents with NAFLD (See Appendix 1).  
9Subjects will complete a hunger and satiety VAS at the indicated time points biweekly and must return completed VAS worksheets for review by study site qualified staff at each study visit.    
10Subjects are expected to follow the study Guidance and Lifestyle Recommendations for Adolescents with NAFLD (Appendix 1).  The Diet and Exercise questionnaire will be a tool for the study 
dietician (or other qualified staff) to help monitor adherence to the guidance throughout the study. The questionnaire is easy to use and requires a simple “yes/no” response. 
11 Subjects are required to fast approximately 8 hours. Prior to their clinic visits on days when blood draws are obtained. On those days, the morning administration of their assigned study food product 
should be held until blood draws are completed.  Subjects may consume their assigned study food product after the blood draw. Site staff should inspect the venipuncture site(s) prior to subject’s 
discharge. 
12 On Day 1, Week 13, and Week 25, subjects will arrive at the study site after having fasted approximately 8 hours.  They will have a fasted blood draw (T=0), will be administered their assigned study 
food product at the study site, and then approximately T=1-2 hours later, another blood sample will be collected for plasma amino acid concentrations. The exact clock times of the T=0 (pre-
administration) and T=1-2 hr (post-administration) samples should be recorded in the source documents.  
13 AXA1957 will be provided to all subjects entering Part 2, there is no placebo. 
14The Follow-Up Visit will occur 2 weeks after Visit 6 for subjects participating in Part 1 only.  The Follow-Up Visit will occur 2 weeks after Visit 10 for those participating in Part 2. 
15 Diary must be filled out over 4 days which should include 2 weekdays and 2 weekend days. Subjects will record to the best of their ability all the typical foods/beverages they eat/drink on those days, 
and their usual physical activity routines to establish a baseline lifestyle pattern.  
16 Randomization will occur only after eligibility is confirmed (including MRI criteria). 
17 A gap between Part 1 and Part 2 of up to 1 week is permitted. 
 

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Abbreviations 
AAP 
American Academy of Pediatrics 
Adipo-IR 
Adipose tissue Insulin Resistance 
AE 
Adverse Event 
ALT 
Alanine Aminotransferase 
Arg 
Arginine 
AST 
Aspartate Aminotransferase 
BCAA 
Branched-Chain Amino Acids 
BHB 
beta- hydroxybutyrate 
BID  
Twice Daily 
PBMC 
Peripheral blood mononuclear cell 
BMI 
Body Mass Index 
BW 
Body weight 
CAP 
Control Attenuation Parameter 
CBD 
Cannabidiol 
CRF 
Case Report Form 
cT1 
Corrected T1 
EC 
Ethics Committee 
ECG 
Electrocardiogram 
EDC 
Electronic Data Capture 
eGFR 
Estimated Glomerular Filtration Rate 
EOS 
End of Study 
GCP 
Good Clinical Practice 
GI 
Gastrointestinal 
GLP-1 
Glucagon Like Peptide 1 
Gln 
Glutamine 
HbA1c 
Hemoglobin A1c 
HDL 
High-Density Lipoprotein 
HIV 
Human Immunodeficiency Virus 
HOMA-IR 
Homeostatic Model Assessment Insulin Resistance 
Ile 
Isoleucine 
ICH 
International Council for Harmonization 
INR 
International Normalized Ratio 
IWRS 
Interactive Web Response System 

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IRB 
Institutional Review Board 
L-car 
L-carnitine 
LDL 
Low-Density Lipoprotein 
Leu 
Leucine 
MODY 
Maturity-Onset Diabetes of the Young 
MRI 
Magnetic Resonance Imaging 
OWL 
One Way Liver 
NAC 
N-acetylcysteine 
NAFLD 
Nonalcoholic Fatty Liver Disease 
NAS 
NAFLD Activity Score 
NASH 
Nonalcoholic Steatohepatitis 
NEFA 
Non-Esterified Fatty Acids 
OAD 
Oral Anti-Diabetic Drug  
PBC 
Primary biliary cholangitis 
PBMC 
Peripheral Blood Mononuclear Cells 
PDFF 
Protein Density Fat Fraction 
PE 
Physical Examination or Product Emergent 
PK 
Pharmacokinetic 
PSC 
Primary sclerosing cholangitis 
RUQ 
Right Upper Quadrant 
SAE 
Serious Adverse Event 
SAS 
Statistical Analysis System 
Ser 
Serine 
SOA 
Schedule of Assessments 
T2D 
Type 2 Diabetes  
TG 
Triglycerides 
TPN 
Total Parenteral Nutrition 
TZD 
Thiazolidinediones 
ULN 
Upper Limit of Normal 
VAS 
Visual Analog Scale 
 
 

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1 INTRODUCTION 
1.1 
Background and Rationale for the Proposed Study 
From 1988 to 2010, the prevalence of nonalcoholic fatty liver disease (NAFLD) increased among 
children and adolescents (Anderson et al., 2015), becoming the most common liver disease in 
children (Welsh et al., 2013), with an overall prevalence of 13%;  the highest rates were seen in 
obese children (38%) (Schwimmer et al., 2006). It is associated with increased risk of type 2 
diabetes, end-stage liver disease, liver cancer, and cardiovascular disease (Chalasani et al., 2012). 
Pediatric guidelines recommend “lifestyle modification to improve diet” (Vos et al., 2017), but do 
not support one specific diet over another because of the limited available evidence.  
The most important rational for doing this study in teenagers is that the metabolic changes that 
result from severe obesity start in childhood and teenage years, and it is this age group who 
potentially have most to benefit in the long term from reduction in liver damage that occurs on an 
ongoing basis. For individuals and society as a whole, this research is potentially more important 
in teenagers and young people than in the adult population. 
Extensive prior literature suggests amino acids can have important physiological and health-related 
effects.  There is evidence that liver health as well as metabolism may be impacted by specific 
combinations of amino acids.  For example, branched chain amino acids (BCAAs), cysteine, and 
arginine have been implicated in enhancing liver health [ (Tajiri & Shimizu, 2013), (Khoshbaten, 
et al., 2010), (Kakumitsu, Shijo, & Yokoyama, 1998)].  Investigations in subjects with type 2 
diabetes (T2DM) showed that the usually reduced insulin response after carbohydrate ingestion 
can almost be tripled by co-ingestion of a free amino acid/protein mixture that contains whey 
protein hydrolysate, free leucine, and phenylalanine (van Loon, et al., 2003). Thus, selective 
supplementation of certain amino acids may have the potential to restore optimal physiological 
processes in the liver.  
Axcella’s amino acid food product, AXA1957, consists of specific combinations of natural amino 
acids that are naturally produced by the body, all of which are normal food ingredients and/or 
readily available as dietary supplements.  The intention and objective of this study is to primarily 
understand the safety and tolerability profile of AXA1957 and its impact on normal liver structure 
and function for up to 25 weeks of administration in adolescent subjects with fatty liver. 
1.2 
Rationale for the Study Design and Amounts of Study Food Product Selected 
The amount of amino acids to be administered in this study are within the known, well tolerated 
ranges for individual or mixtures of amino acids administered to humans in several published 
studies, including repeated administrations in people with T2DM and/or metabolic syndrome 
(Table 2). These amounts are also similar to readily available over-the-counter amino 
acid/dietary supplement formulations including amounts present in food (Table 2). 

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Table 2. Amounts of AXA1957 Components Present in Diet 
Components within 
AXA1957 
Amount 
Present in 
AXA1957 
Maximum 
Daily 
Amount 
(g) 
Common OTC 
Dietary Supplement 
Formulations Daily 
Amount (g) 
Adult RDA 
(g, assuming 
70 kg) 
Mean in 
Diet (g) 
99th 
Percentile in 
Diet (g) 
Leucine (L) 
6 
5 
NutraBio BCAA 
5000 (GNC), BID 
suggested regimen 
2.94 a 
6.08 a,b 
12.70 a,b 
Isoleucine (I) 
3 
2.5 
NutraBio BCAA 
5000 (GNC), BID 
suggested regimen 
1.33 a 
3.55 a,b 
7.28 a,b 
Arginine (R) 
8 (given as 
9.67 g R-
HCl) 
5 
GNC L-Arginine 
5000MG, QD 
suggested regimen 
NA 
4.18 a,b 
9.10 a,b 
Glutamine (Q) 
4 
5  
Pro Performance L-
Glutamine (GNC), 
QD post-exercise 
suggested regimen 
NA 
6.85 c 
NA 
N-acetylcysteine 
(NAC) 
2.6 
up to 3.6 
NutraBio Amino 
Therapy NAC 
(GNC), upper 
suggested dose, BID 
suggested regimen 
NA 
NA 
NA 
L-carnitine (L-car) 
2 
2 
Beyond Raw 
Chemistry Labs L-
Carnitine (GNC) 
NA 
0.07 d 
NA 
Serine (S) 
15 
2 
Bulk Supplements 
L-Serine 
NA 
3.51 a,b 
7.15 a,b 
a Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino 
Acids (Macronutrients). (2005). pg 680, 988-1027.  https://doi.org/10.17226/10490 
b All Individuals except pregnant and lactating 
c Healthy women aged 30-55 (Lenders et al., 2009) 
d Adult omnivores assuming 70kg (Rebouche and Engel, 1984)  

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It is well documented that children have an increased rate of protein deposition due to growth and 
this rate decreases with age (“Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, 
Fatty Acids, Cholesterol, Protein, and Amino Acids (Macronutrients),” 2005).  The estimated 
average requirement (EAR) and recommended dietary allowance (RDA) for protein and individual 
essential amino acids are higher in younger populations than adults on a g/kg basis (“Dietary 
Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and 
Amino Acids (Macronutrients),” 2005).  For BCAAs, it has been reported that the EAR, as 
estimated by the indicator amino acid oxidation (IAAO) method, is increased in children compared 
with adults (Mager, Wykes, Ball, & Pencharz, 2003; Riazi, Wykes, Ball, & Pencharz, 2003) and 
is further increased in children with mild to moderate chronic cholestatic liver disease (Mager, 
Wykes, Roberts, Ball, & Pencharz, 2006) compared with healthy adolescents.  It is therefore likely 
that the proposed amounts of AXA1957 to be administered to adolescents will result in exposure 
that is comparable, if not lower than that achieved when given to adults.   
The amino acid components of AXA1957 have had safe upper limits of intake (UL) or no observed 
adverse event levels (NOAEL) suggested in literature based on studies in human adults. An UL 
for Leucine has been suggested at 35 and 30 g/day in healthy young men and healthy elderly men 
respectively based on the maximum rate of oxidation as determined by IAAO and assuming a 70 
kg body weight (Elango, Chapman, Rafii, Ball, & Pencharz, 2012; Rasmussen, Gilbert, Turki, 
Madden, & Elango, 2016). The Leu amount in AXA1957 is 9 g/day (see Table 3).  An observed 
safe level (OSL) for Arginine has been suggested at 30 g/day (McNeal, Meininger, Wilborn, 
Tekwe, & Wu, 2018) while an OSL at 20 g/day and a NOAEL at 30 g/day in healthy adults has 
also been suggested (Shao & Hathcock, 2008). Arg amount in AXA1957 is 8 g/day (see Table 3).   
An OSL and NOAEL for Glutamine has been suggested at 14 g/day and >45 g/day respectively 
(Shao & Hathcock, 2008). Glutamine amount in AXA1957 is 4 g/day (see Table 3).  An OSL of 2 
g/day has been suggested for Carnitine (Hathcock & Shao, 2006). L-Car amount in AXA1957 is 
up to 2 g/day (see Table 3).  OSL or NOAELs for the other components (such as Ser, Ile) are not 
currently available.  
As noted above and detailed further in Table 2, all these ULs are at or above the amounts of the 
individual AAs within AXA1957.  While comparable studies have not been performed to 
establish UL or NOAEL values in adolescent populations, the Sponsor is not aware of any 
evidence suggesting that adolescents would have a lower tolerance for amino acid exposure than 
adults.  In fact, the increased protein requirements and the increased rate of protein deposition in 
children and adolescents suggests that a lower plasma exposure would be achieved in the 
proposed adolescent population. 
 

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Table 3. Summary of Studies Supporting the Administration of the Components within 
the AXA1957 Food Product 
Components 
within 
AXA1957  
Daily amounts 
within 
AXA1957  
Amounts 
/duration/safety in 
relevant prior adult 
clinical studies 
Available data on 
amounts/duration/safety in 
pediatric patients 
Leucine 
(L), 
Isoleucine (I),  
9g/day of L & I 
at a 2:1 ratio  
12g/day of L/I/V at 2:1:1 
ratio → 6/3/3 g/day each 
of LIV in patients with 
liver cirrhosis over a 2-
year period (Muto et al., 
2005). Adverse events 
reported in 12% of 
BCAA cohort in Muto 
study primarily 
gastrointestinal problems 
such as abdominal 
distension, diarrhea and 
constipation (Muto et al., 
2005) 
BCAA dosed 0.33-0.39 
g/kg/day L/I/V at 1.7:1:1.5 
ratio as part of enteral nutrition 
formula delivered 
nasogastrically for 8 weeks in 
19 pediatric end-stage liver 
disease patients, 10 completed 
study aged 0.7-5.9 years, 
incidence of complications of 
liver disease was similar in 
both treatment arms - BCAA-
enriched and isonitrogenous 
enteral nutrition (Chin et al., 
1992; Ooi, Gilmour, Yap, & 
Mager, 2018) 
(i.e. 6g L & 3g I 
per day total); 
0g V  
30g/day of oral BCAA 
(13.5g L, 9g I) in patients 
with cirrhosis and prior 
hepatic encephalopathy 
over 56 weeks 
(NCT00955500). No 
safety/tolerability 
reported in 
NCT009555000 
BCAA being dosed up to 27 g 
BID L/I/V at 1:1:1 ratio for 21 
days in NCT01860404 (Status: 
Recruiting), safety information 
not yet available, in children 
and adults aged 11-34 years 
Arginine (R) 
8 g/day 
9g/day R given to 
patients with T2D for 3 
months to study 
microcirculation 
(NCT00902616). No 
safety/tolerability 
reported in 
NCT00902616 
0.1 g/kg TID oral or IV 
infusion Arg-HCl up to 30 
g/day max for 5 days in 
children and adults with sickle 
cell disease aged 3-21, no 
serious drug-related adverse 
events observed, 
although one AE and one SAE 
occurred that led to 
discontinuation of the study 
drug (Morris et al., 2013) 
(given as 9.67g 
R-HCl) 
9g/day R given to T2D 
patients for 1 month to 
improve peripheral and 
hepatic insulin 
sensitivity. No 

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Table 3. Summary of Studies Supporting the Administration of the Components within 
the AXA1957 Food Product 
Components 
within 
AXA1957  
Daily amounts 
within 
AXA1957  
Amounts 
/duration/safety in 
relevant prior adult 
clinical studies 
Available data on 
amounts/duration/safety in 
pediatric patients 
safety/tolerability 
reported (Piatti et al., 
2001). 
Glutamine (Q) 
4 g/day 
15g/day for 8 weeks used 
to treat patients with 
Irritable Bowel 
Syndrome (TID as 
5g/dose) 
(NCT01414244). No 
AEs reported in the study 
Approximately 0.3 g/kg/day up 
to 30 g/day max for 48 weeks 
in children and adults with 
sickle cell disease aged 5-58 
years (NCT01179217). The 
rate of adverse events was 
higher in the placebo group 
than in the l-glutamine group 
(100% vs. 98.0%), as was the 
rate of serious adverse events 
(87.1% vs. 78.2%), low-grade 
nausea, noncardiac chest pain, 
fatigue, and musculoskeletal 
pain occurred more frequently 
in the l-glutamine group than 
in the placebo group (Niihara 
et al., 2018) 
N-
acetylcysteine 
(NAC) 
2.6 g/day 
NAC improves liver 
function in patients with 
non-alcoholic 
steatohepatitis (NASH) at 
1.2 g/day for 3 months 
(Khoshbaten et al., 
2010). No AEs in 
patients with NASH 
Up to 2.7 g/day thrice daily for 
4 weeks at high dose (12 
weeks total) in children with 
autism aged 3-12 years. 
Minimal adverse effects were 
observed except for one 
subject in the active group who 
experienced worsening of 
baseline agitation and 
irritability requiring early 

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Table 3. Summary of Studies Supporting the Administration of the Components within 
the AXA1957 Food Product 
Components 
within 
AXA1957  
Daily amounts 
within 
AXA1957  
Amounts 
/duration/safety in 
relevant prior adult 
clinical studies 
Available data on 
amounts/duration/safety in 
pediatric patients 
3-4g/day for 14 days in 
mild traumatic brain 
injury (Hoffer, Balaban, 
Slade, Tsao, & Hoffer, 
2013).  NAC produced 
no side effects in subjects 
with blast-induced 
traumatic brain injury 
termination followed by 
symptom resolution.  This 
participant exhibited the same 
behavioral worsening 6 weeks 
after being terminated from the 
study, which led to a medical 
evaluation that revealed severe 
constipation.  Most adverse 
effects were gastrointestinal, 
consistent with previous 
reports, no statistical 
significance between NAC and 
placebo groups was detected 
from chi-square tests for 
individual side effects (p = 
0.198) or all gastrointestinal 
adverse effects combined (p = 
0.199) (Hardan et al., 2012) 
L-carnitine (L-
car) 
2 g/day 
2g/day supplement added 
to diet for 24 weeks 
improved liver function 
and histological 
manifestations of NASH 
(Malaguarnera et al., 
2010). Carnitine was well 
tolerated in all patients, 
with mild AEs reported 
in 5/36 subjects: 1 
nausea, 2 headaches, 2 
abdominal pain 
0.1 g/kg twice daily up to 4 
g/day max in boys aged 6-13 
years with ADHD. Two boys 
broke their arm due to their 
hyperactive behavior during 
the placebo period. One boy 
had a short unexplained period 
of fainting a few days after the 
onset of the placebo period 
following carnitine. One boy 
had an elevated plasma 
creatinine level during the last 
placebo period, but 2 weeks 
after the trial, a normal level 
was found. Physical 
examination of all boys by the 
pediatrician at the end of the 
three trial periods showed no 
abnormalities. One patient 
observed an unpleasant body 

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Table 3. Summary of Studies Supporting the Administration of the Components within 
the AXA1957 Food Product 
Components 
within 
AXA1957  
Daily amounts 
within 
AXA1957  
Amounts 
/duration/safety in 
relevant prior adult 
clinical studies 
Available data on 
amounts/duration/safety in 
pediatric patients 
odor during treatment with 
carnitine, a well-known side 
effect, likely due to the 
formation of trimethylamine 
(Oudheusden & Scholte, 2002) 
Serine (S) 
15 g/day 
20g/day Ser was 
administered for 14 days 
in NAFLD patients 
(Mardinoglu et al., 2017). 
No AEs reported, S was 
well tolerated 
400 mg/kg/day (28 g/day 
in 70 kg adult) well-
tolerated in adult subjects 
with HSAN1 (Fridman et 
al., 2019)a 
Case reports of serine in 
infants and juveniles with 3-
PGDH deficiency at doses 
ranging from 100-700 
mg/kg/day (7-49 g/day in 70 
kg). No safety/tolerability 
information reported 
(Tabatabaie et al., 2011) 
a Serine is a non-essential amino acid synthesized from glucose in the body It is readily interconverted with 
glycine and metabolized in the TCA cycle. A serine dose of 400 mg/kg/day in subjects with HSAN1 resulted in a 
non-significant relative increase in plasma levels relative to placebo, likely due to rapid metabolism in liver and 
muscle (Fridman et al., 2019). 

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Based on the proposed amounts in AXA1957 (i.e. all at or below established ULs), and an 
extensive prior published scientific and clinical literature that have demonstrated the safety and 
tolerability of each amino acid present within AXA1957 in both the adult and pediatric 
populations, it is anticipated that administration of AXA1957 in an adolescent population will also 
be safe and well tolerated.    
In addition, the proposed design incorporates a judicious escalating administration scheme (i.e. 
6.7g BID for 3 days, and only if well-tolerated, 13.5g BID for up to 24 weeks. Such a design 
ensures monitoring for any unanticipated tolerability issues, and to gradually attain sufficient 
exposure of the AAs to adequately evaluate the safety and tolerability of this food product in a 
fatty liver population.  At any time during the study, the design also allows for a down-titrating of 
the amounts that were previously shown to be well tolerated (e.g., from 13.5g BID to  6.7g BID).      
The safety and tolerability of AXA1957 is also being studied over a duration of 16 weeks in an 
adult population of NAFLD with or without diabetes (Study AXA1125-003). This study is 
currently ongoing. The primary goal of the study is examination of the safety and tolerability of 2 
different AXA compositions (AXA1125 and AXA1957), in addition to an exploration of the effect 
of AXA compositions on metabolism, especially amino acid and lipid metabolism, as well as liver 
structure and function. As it is a single blind study, safety and tolerability data are being  analyzed 
on an ongoing basis on all available adult subjects enrolled in the study. An interim analysis of all 
subjects in  the trial as of October 15, 2019 was performed and the data demonstrate that both 
amounts of AXA1957 are generally safe and well-tolerated.     
As of 15-October-2019, a total of 58 adult subjects have received at least one dose of  AXA1957 
at either 13.5 g BID or 20.3g BID, with 31 subjects who have completed at least 8 weeks of study 
product administration and 28 subjects who have completed 16 weeks of study product 
administration (Axcella, data on file as of October 15, 2019). These preliminary data show a total 
of 69 study product emergent AEs in 58 subjects assigned to AXA1957 at either 13.5 g BID or 
20.3g BID regimen have been reported to date (Table 4). All AEs to date during AXA1957 
administration have been mild or moderate. Of the 69 total AEs, 13 were considered to be possibly 
or probably related to study product.  Three subjects had dosing interruptions or discontinuations 
during study: one subject with transient diarrhea and abdominal bloating who subsequently was 
diagnosed with nephrolithiasis and discontinued administration (20.3g BID); one subject with 
transient moderate abdominal pain and diarrhea, who interrupted treatment due to moderate 
abdominal pain, diarrhea and nausea and subsequently withdrew from the study (20.3g BID), and 
another who had moderate nausea and discontinued study product (13.5g BID). There were no 
serious adverse events reported in subjects administered AXA1957.   

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There was no difference in this interim analysis between the AXA arms in terms of the number of 
AEs, study product-emergent AEs, reported severity or pattern of adverse events (Table 4). Of the 
product-emergent AEs, the majority of those considered to be possibly or probably related to 
AXA1957 were related to the gastrointestinal system (9/13), such as diarrhea, nausea, abdominal 
pain and distension. There was no vomiting thought to be related to study product. In terms of 
severity, all reported AEs in the AXA1957 arms were mild (17/33, 51.5%) or moderate (16/33, 
48.4%). The only adverse events of moderate severity reported in 2 or more subjects were nausea 
(N=2, both 13.5g BID) and abdominal pain (N=2, both 20.3g BID). There were no clinically 
significant changes in safety laboratory (chemistry and hematology) parameters, vital signs, EKGs, 
or physical exam findings. Taken together, AXA1957 at both amounts continues to be well 
tolerated in adults with NAFLD.  
In sum, there is no pattern in the evaluation of safety and tolerability to suggest that there is a dose 
response relationship in terms of the pattern or severity of AEs in subjects administered AXA1957. 
 Table 4. Summary of Adverse Events in Study AXA1125-003 in the Safety Population 
(observed as of 15 October 2019; reported in 2 or more subjects) 
Adverse Events 
Placebo (N=15) 
AXA 20.3g BID 
(N=29) 
AXA1957 13.5g BID 
(N=29) 
Total Number of Product 
Emergent (PE) AEs 
17 
33 
36 
Any product-emergent 
AE 
8 
15 
18 
Dosing Disc., Inter. or 
Reduc. due to a PE AE 
1 
2 
1 
 
 
 
 
Gastrointestinal 
Disorders 
2 (13.3) 
11 (37.9) 
9 (31.0) 
Diarrhea  
1(6.6) 
5 (17.2 
3 (10.3) 
Nausea 
1 (6.7) 
3 (10.3) 
3 (10.3) 
Abdominal Pain 
0 
3 (10.3) 
1 (3.4) 
Abdominal 
Distension 
1 (6.7) 
2 (6.9) 
0 
Metabolism and nutrition 
0 
2 (6.9) 
3 (10.3) 
Decreased 
appetite 
0 
1 (3.4) 
2 (6.9) 
Infections 
1 (6.7) 
4 (13.8) 
5 (17.2) 
Urinary Tract 
Infection 
0 
0 
2 (6.9) 
Nervous System 
Disorders 
2 (13.3) 
1 (3.4) 
4 (13.8) 
Headache 
1 (6.7) 
0 
3 (10.3) 
Musculoskeletal 
Disorders 
1 (6.7) 
2 (6.9) 
1 (3.4) 
Pain in Extremity 
0 
2 (6.9) 
1 (3.4) 

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In terms of biological effects, an interim analysis was done on subjects in the AXA1125-003 trial 
who had at least one post baseline MRI, had sufficient information on dosing to evaluate 
compliance as being greater than 80% and had no major protocol deviations (N= 7 for placebo, 15 
for AXA1957 20.3 g BID and 16 for AXA 1957 13.5g BID). Of these, 8,12, and 16 subjects had 
completed 16 weeks of product administration in the placebo, AXA1957 20.3g BID and AXA 
1957 13.5g BID arms, respectively as of October 15,  2019.  
Review of the interim data for AXA 20.3g BID and 13.5 g BID amounts suggested that there were 
clinically meaningful biological effects observed at both amounts.  On some measures (i.e. proton 
density fat fraction (PDFF) and corrected T1 (cT1), imaging assessments of the degree of hepatic 
steatosis and liver injury, respectively), the lower amount of AXA1957 appears to perform better 
than the higher amount (Table 5). On other laboratory-based assessments (e.g., ALT, CK18, 
proC3, markers of liver injury and fibrogenesis), the differences appear to be less apparent between 
the two AXA1957 amounts (Table 5).  This study is ongoing; nonetheless, review of the biological 
data on balance suggest that administration of the 13.5g BID amount is likely to have a 
qualitatively greater than or equivalent effect on metabolism and organ function as the 20.3g BID 
amount.   
Table 5. Interim Analysis of the Effects of AXA1957 on Metabolism and Organ Structure 
and Function from Study 1125-003 (Week 16) 
Measure 
Placebo       
(N=7) 
AXA 20.3g BID 
(N=15) 
AXA1957 13.5g 
BID (N=16) 
Relative change in PDFF (%) 
-0.15 
-5.37 
-23.59 
Absolute change in PDFF 
0.05 
-1.13 
-4.52 
cT1 (mSec change) 
30.3 
3.5 
-64 
CK-18 (% change) 
-12.7 
-11.14 
-11.99 
Pro-C3 (% change) 
-5.68 
-27.8 
-7.59 
 
Taken together, after review of all available safety, tolerability, and biological data to date with 
AXA1957 at both 8 and 16 weeks in adult subjects with NAFLD, the amount of AXA1957 in 
adolescents is proposed as 13.5g BID. Given the anticipated weights of the adolescents in this 
study, biologic effects as related to intake amount are expected to be similar.   Also, based on the 
accumulated data to date on these food products by the Sponsor, the anticipated additional ongoing 
study with AXA1957 in adult NAFLD subjects, and the  extensive published literature [(Børsheim 
et al., 2009; Coker et al., 2015; Dreyer et al., 2008; Hurt et al., 2014; Huynh & Tayek, 2002; 
Jabłecka et al., 2012; McClure et al., 2014; Scarnà et al., 2003; Scolapio, McGreevy, Tennyson, 
& Buett, 2001; Williams et al., 2004); see Table 3 above],  on specific amino acids as well as 
mixtures of amino acids across a variety of adult and pediatric populations and disease conditions, 
it is anticipated that safety and tolerability profile of AXA1957 in the proposed adolescent 
population of fatty liver would be similar to, or better, than that observed in prior studies.   
 
 

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2 OBJECTIVES 
2.1 
Study Objective  
To assess the safety, tolerability, and parameters of liver health in adolescent subjects with fatty 
liver when administered AXA1957, an amino acid food product. 
2.2 
Study Assessments 
Safety and tolerability will be assessed by: 
x Reported clinical adverse events (AEs) 
x Physical examinations, including changes in body weight and body composition such 
as lean mass and fat mass 
x Vital sign assessments 
x Electrocardiograms (ECGs) 
x Clinical laboratory tests including changes in standard haematology, chemistry, and 
lipid panels  
Liver structure and function will be assessed by: 
x Multiparametric magnetic resonance imaging (MRI) assessments of liver structure (fat 
content and inflammation changes) 
x Blood tests of liver function, including markers of inflammation and fibrosis 
 
 

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3 INVESTIGATIONAL PLAN 
3.1 
Overall Study Design and Plan 
This is a randomized, placebo-controlled study conducted in 2 Parts: a mandatory 13-wk 
administration period (Part 1) and an optional extension period up to a maximum of 12 additional 
weeks (Part 2); see Figure 1 below.   
 
Figure 1. Study Schematic 
 
 
 
 
 
 
 
 
 
Total duration of the study from Screening to the end of Part 2 follow-up is anticipated to be 
approximately 31 weeks. It is anticipated that there may be a total of approximately up to twelve 
(12) study visits during the entire study (Screening, Parts 1 and 2).  
In Part 1, following up to a 4-week screening period, eligible subjects will be randomized in a 2:1 
ratio to receive either AXA1957 or placebo for a 13-week administration period.  
Subjects will be centrally randomized with gender (male/female) as the stratification factor to 
AXA1957 or placebo groups.   Randomization will occur via an interactive web response system 
(IWRS) after eligibility is confirmed and prior to the Day 1 Visit. Study food product amounts will 
be gradually escalated through the first week of study participation to assess tolerability issues to 
the food product during the initial week, and to enable subjects and their caregivers to get 
accustomed to the twice daily regimen. Safety and tolerability will be monitored throughout the 
study.  
All subjects will be provided Guidance and Lifestyle Recommendations for Adolescents with 
NAFLD; see Appendix 1.  
Following the mandatory Part 1 period, all subjects including those randomized to the placebo-
arm in Part 1, will have an option to continue in the study in Part 2 for up to an additional maximum 
of 12 weeks on the AXA1957 food product.  All subjects who opt to enter Part 2 will be 
administered AXA1957 at the same amount and regimen as in Part 1 (i.e. up to 2 stick packs twice 
daily starting from Week 14) and will continue to be provided the standard lifestyle guidance.  
Subjects who choose not to participate in Part 2, will undergo a safety follow up visit 
approximately 2-weeks after Visit 6 per the procedures in Schedule of Assessments (SOA) Table 
1. There will be a 2-week follow up period after subjects complete Part 2.   
Extension subjects
AXA1957 (12 weeks) 
PBO (1+12 weeks)
MRI
Up to 28 days 
PART 1
Mandatory AXA1957 or
Placebo Administration Period (13 weeks)
W1
R
W3 
W10
W7 
MRI
AXA1957 (1+12 weeks)
PART 2
Optional AXA1957 Extension
Period (up to a maximum of 12 weeks)
MRI
W15
W13
W25
W27
Screening Period
( 28 days )
Follow-up
(2 wks)
2 wks
Includes a 4 - day period to 
collect baseline diet and 
physical activity pattern, 
and screening MRI 
IA #2
50%
n=20
n=10
MRI
IA #1
50%
W19
W22
PK 
PK
D1

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If subjects drop out at any time for any reason during either Part 1 or 2 of the study, including the 
follow up period, their last visit should capture all the assessments as the end-of-study assessments 
as shown in Table 1. 
3.2 
Study Blinding 
Part 1 is a single-blind design. Subjects will be blinded to study food product assignment 
(AXA1957 or placebo), but site personnel dispensing the product to subjects and the Sponsor will 
be unblinded.  Part 2 is open label. All subjects will receive AXA1957 for an additional 12 weeks. 
3.3 
Study Dietary and Physical Activity Requirements 
Diet and exercise regimens play an important role in subjects with NAFLD and can possibly 
impact study outcome measures.  In order to control for this variable, all enrolled subjects will be 
provided study Guidance and Lifestyle Recommendations for Adolescents with NAFLD (See 
Appendix 1).  All sites will provide the uniform guidance to ensure that subjects are receiving 
consistent diet and exercise instructions across different sites.  The Sponsor will provide 
instructions to study sites on how to provide the guidance to enrolled subjects.  Qualified site staff 
will provide the guidance and answer any questions subjects and/or their family have during all 
visits starting at Visit 1.  During weeks where there are no study visits, the qualified site staff will 
call subjects to reinforce the guidance and address questions.  Subjects will also be provided diaries 
to help track and monitor diet and exercise patterns throughout the study to the best of their ability. 
3.4 
Screening Period 
Once written informed consent/assent is obtained, screening procedures will be completed per the 
SOA in Table 1. Screening period may be up to 4 weeks before starting Part 1.  During this period, 
subjects will be asked to complete a diet and exercise diary over  4 days, which should include two 
weekdays and 2 weekend days.  Subjects will record to the best of their ability all the typical 
foods/beverages they eat/drink on those days, and their usual physical activity routines to establish 
a baseline lifestyle pattern. During the entire screening period subjects should continue their 
normal habitual diet, physical activity patterns and routines (e.g., school, extracurricular activities, 
including their usual sports activities), and their prescribed standard of care therapies, if applicable 
Subjects are also be required to undergo a screening multiparametric MRI scan within 
approximately 7 days before potential randomization. Subjects will be instructed to fast for at least 
4 hrs. prior to their scheduled MRI subjects will have to meet the screening MRI criteria to be 
eligible for randomization.      
Subjects who screen fail due to ALT may be re-screened one time.   
Subjects who meet the criteria for inclusion in Version 2.0 of the Protocol may be rescreened for 
Version 3.0 of the Protocol. If more than 30 days have lapsed since laboratory assessments have 
been completed as part of Screening, these assessments should be repeated.  If an ultrasound or 
Fibroscan was used to confirm the presence of NAFLD, these do not need to be repeated.  If the 
baseline MRI was performed, this does not need to be repeated providing the interval between the 
MRI and randomization is less than 14 days and there has been no significant weight change (e.g., 

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>5%). Other inclusion and exclusion criteria should be confirmed with the same time bounds as 
noted. 
3.4.1 
Randomization 
Following completion of all Screening procedures, eligible subjects will be randomized in a 2: 1 
ratio to receive either AXA1957 or Placebo and stratified by gender with a block of size of 3.  
3.5 
Part 1: Mandatory Administration Period 
3.5.1 
Visit 1 / Day 1 and up to Week 1 
Eligible subjects will be randomized via the IWRS and will receive either placebo or AXA1957 
with instructions (to both subjects and their caregivers) on how to prepare and consume the study 
food product, including timing of administration.  
On Day 1, subjects will arrive to the study site following an overnight fast of approximately 8 
hours.  Prior to study product administration, subjects will undergo fasting blood draws and other 
assessments per the SOA in Table 1. The first administration of the study food product will be at 
the study site supervised by the study staff. After the study food product administration, subjects 
will have one additional blood draw for plasma amino acid concentration approximately 1-2 hours 
after the study product administration and then discharged from the study site.   
During the Day 1 visit, all subjects will be provided Guidance and Lifestyle Recommendations for 
Adolescents with NAFLD (See Appendix 1). Qualified site staff will explain these 
recommendations and answer any questions the study participant and/or their family may have.   
During the first week of study product administration in both AXA1957 and placebo groups, 
subjects will follow the administration schedule below: 
- 
Days 1 to 3: 1 stick pack twice daily (total of 2 stick packs daily) 
- 
Days 4 through the remainder of the study: 2 stick packs twice daily (total of 4 stick packs 
daily) 
Twice daily regimen of the food product should occur within 30 minutes (i.e. 30 ±5 minutes) 
before meals (e.g., before breakfast and dinner or before lunch and dinner, if breakfast is not a 
usual part of their daily routine).  Any adjustments to this regimen or amount may be considered 
on a case-by-case basis (see additional details under Study Food Product Section below).   
Site staff will conduct a phone call on Day 3 to assess tolerability, and if tolerated, remind the 
subject to increase the food product to 2 stick packs twice a day (4 stick packs daily) for the 
remainder of the study administration period. 
3.5.2 
Visit 2 (Week 1), Visit 3 (Week 3), Visit 4 (Week 7), Visit 5 (Week 10) 
& Visit 6 (Week 13): 
All procedures during Visits 2 through 6 will be performed per the SOA in Table 1.  Subjects will 
be asked to bring all their study food product stick packs (full and empty) to each clinic visit for 
site staff to perform accountability. Subjects are also required to bring their study food product 
administration and lifestyle diaries for review at each clinic visit.  

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During weeks where there are no clinic visits, study staff will make approximately weekly phone 
calls to subjects to ensure compliance with the study food product administration/regimen, collect 
information regarding adverse events and concomitant medications, answer any questions, and 
check-in with subjects/caregivers. If the subject reports new medications, this should be carefully 
reviewed against the list of prohibited medications in Section 6.1. 
 
3.6 
Part 2: Optional Extension Period (12 weeks) 
3.6.1 
Visit 6 (Week 13) Visit 7 (Week 15), Visit 8 (Week 19), Visit 9 (Week 
22) & Visit 10 (Week 25):    
After the completion of the mandatory 13-week period (Visit 6), all subjects from Part 1 have the 
option to enter Part 2 where participating subjects (including those that received placebo in Part 
1) will receive up to a maximum of 12 additional weeks of AXA1957 food product.   
The determination of whether to continue in the optional period is based upon the following:  
x The subject is willing and able to participate in the study for up to 12 additional weeks, 
and  
x There are no negative signals as determined by the clinical judgement of the study 
medical monitor, investigator, dietician, and/or Sponsor after carefully considering 
safety, tolerability, health status, body weight, body composition, MRI, and/or blood 
parameters. 
Subjects do not participate in Part 2 will undergo an end-of-study follow up visit approximately 
2-weeks after Visit 6 per procedures in the SOA in Table 1.  
Subjects who participate in Part 2 will be provided a supply of AXA1957 study food product at 
Visit 6 and will be instructed to start consuming 2 stick packs twice daily. 
There will be at least 4 study visits in Part 2, and all procedures during those visits will be 
performed per the SOA in Table 1. Safety and tolerability of the study food product will continue 
to be assessed as was in Part 1.  
If subjects drop out at any time for any reason during the study, their last visit should capture all 
the assessments as the end-of-study assessments as shown in Table 1.  Subjects will not be replaced 
in Part 2. 
3.7 
Follow-up Visit  
Subjects who participate in Part 1 only will return to the study site for a follow-up visit 
approximately 2-weeks after Visit 6 and will follow the SOA procedures per Table 1.  
Subjects who opt to participate in Part 2 will return to the study site for a follow-up visit 
approximately 2-weeks after Visit 10 and will follow the SOA procedures per Table 1. 
 

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3.8 
Early Discontinuation/Early Termination Visit 
If subjects drop out at any time for any reason during either Part 1 or 2 of the study, including the 
follow up period, they are expected to complete an Early Termination Visit and will follow the 
SOA procedures per Table 1. 
Subjects who discontinue early in Part 1 may be replaced; subjects who discontinue in Part 2 will 
not be replaced. 
 
4 SELECTION OF STUDY POPULATION 
Subjects who meet inclusion criteria and do not meet any of the exclusion criteria will be eligible 
for enrollment into the study. 
4.1 
Inclusion Criteria 
Subjects must meet all the following criteria to be eligible to participate in the study: 
1. 
Male and female adolescent subjects between 12 and 17 years of age, inclusive.   
2. 
Female subjects must be at least 2-year post-menarche as determined by clinical 
history.  
3. 
Willing and able to provide written informed consent from parent(s) or legal 
guardian, as required. 
4. 
Willing and able to provide written assent from subject, as required. 
5. 
Stated willingness and ability of parent/guardian and the subject to take the study 
food product twice a day and adhere with all study procedures and requirements.  
6. 
Body weight ≥ 60 kg at time of screening and subjects should be within ±5% of 
their body weight over the last 30 days prior to Screening 
7. 
Subjects should be at risk for fatty liver, which can be assessed by any one (1) of 
the following:  
a. 
Historical liver biopsy that was obtained up to 6 months prior to Screening 
(local pathology interpretation may be used) with Steatosis greater than 
Grade 1, if applicable as part of standard of care. 
Note: For the historical liver biopsy to satisfy the fatty liver 
requirement, the biopsy must have been obtained with no NAFLD 
or NASH treatment, medications that can cause steatosis or NASH, 
or other interventional agents/procedures  for the treatment of 
NAFLD/NASH within 3 months prior to when the liver biopsy was 
obtained; OR                                                
b. 
Fasting ALT ≥ 50 U/L in boys, ≥45 U/L in girls, and ≤ 150 U/L in both 
genders in the Screening visit labs; OR 

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c. 
Fibroscan with Control Attenuation Parameter (CAP) ≥ 280 dB/m obtained 
within 90 days of Randomization; OR 
d. 
Any of the following right upper quadrant ultrasound sonographic features 
suggestive of hepatic steatosis obtained within 90 days of Randomization, for e.g.: 
liver uniformly heterogeneous; echogenic diffusely with bright hepatic echoes 
within the first 2-3 cm of depth with increased hepatorenal echogenicity (i.e., liver 
with areas of significantly increased echogenicity relative to the renal parenchyma); 
attenuation of image quickly within 4-5 cm of depth making deeper structures 
difficult to decipher; thick subcutaneous depth (> 2 cm);  vascular blurring of portal 
or hepatic vein.    
8. 
MRI Proton Density Fat Fraction (PDFF) > 10% and corrected T1 (cT1) > 820msec 
using multiparametric MR imaging of the liver.    
Note: Screening MRI should occur approximately within 7 days prior to 
randomization and must NOT occur until each of the above entry criteria #1 
through #7 have been confirmed.   
9. 
Subjects may have either prediabetes or type 2 diabetes (T2DM). Prediabetes is 
established by one of the following: 
a. 
Fasting Blood Glucose is ≥100 mg/dL (5.5 mmol/L) but <126 mg/dL (7.0 
mmol/L)  or HbA1c ≥5.7% but < 6.4% based on the Screening visit labs; 
OR 
b. 
Historical evidence (i.e. within 3 months of Randomization) of impaired 
fasting glucose/glucose intolerance per the standard of care guidelines and 
usual procedures of the study center; OR 
c. 
Subject is already on a stable regimen for approximately 60 days prior to 
Randomization for the treatment of prediabetes (e.g., diet/lifestyle, 
metformin, etc.).   
10. 
Subjects with Investigator-confirmed T2DM should have HbA1c <9.5% at 
Screening and must be stable on their usual diabetic medications for approximately 
60 days prior to Randomization and should not be anticipating clinically significant 
dose adjustments of the T2DM medications for the anticipated duration of the study. 
11. 
Subjects taking vitamin and/or other dietary/herbal supplements are permitted as 
long as ALL the following are met: 
a. 
Vitamin(s) or other supplement(s) are not on the list of prohibited 
medications (see Section 6.1.1), and 
b. 
Subject has been on stable doses and regimens for at least 2 months prior to 
Randomization; however, if vitamin E is at doses ≥400 IU/day it must be 
discontinued prior to Randomization if the subject otherwise qualifies into 
study, and  
c. 
There are no anticipated dose adjustments or changes (i.e. stopping or 
adding) of vitamins/supplements for the duration of the entire study, 
including the optional extension period. 

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12.  
Heterosexually active female participants of childbearing potential (i.e. post-
pubertal and /or post-menarchal, not surgically sterile [defined as tubal ligation, 
hysterectomy, or bilateral oophorectomy]) must agree to abstain from sexual 
intercourse for the entire duration of the study (i.e., from time ICF is signed to end-
of-study follow up) as any hormone-based contraception approaches are not 
allowed in the study (e.g., oral contraceptive pills are excluded medications for this 
study), and barrier approaches (e.g., condom with spermicide, diaphragm with 
spermicide) alone are not considered adequate to prevent pregnancy. Sexual activity 
will be ascertained at each study visit, and every female participant in the study 
must complete a required pregnancy test at each study visit.   
4.2 
Exclusion Criteria 
Subjects are not eligible to participate in the study if any of the following criteria are met:  
1. 
History of any acute or chronic liver disease, other than non-alcoholic fatty liver 
disease, 
such 
as 
drug-induced, 
autoimmune, 
or 
any 
viral 
hepatitis, 
hemochromatosis, Wilson’s, primary sclerosing cholangitis. Clinical/medical 
history or appropriate laboratory /serological assessments, if necessary, may be 
relied upon to rule out these other causes of liver disease.   
2. 
Known positive for human immunodeficiency virus (HIV)  
3. 
Presence of Stage 4 fibrosis in the liver 
4. 
Non-compensated liver disease with any one of the following hematologic, 
biochemical, and serological criteria at Screening: 
a. 
Hemoglobin < 10 g/dL 
b. 
White blood cell < 3,500 cells/mm 
c. 
Neutrophil count < 1,500 cells/mm3 of blood 
d. 
Platelets < 130,000 cells/mm3 of blood 
e. 
Direct bilirubin > 1.0 mg/dL (>17.1 Pmol/L) 
f. 
Total bilirubin ≥ 3 mg/dL (≥51.3 Pmol/L, unless Gilbert’s Syndrome).  
However, subjects with Gilbert’s syndrome with direct bilirubin above 
upper limits of normal (ULN) in addition to total bilirubin ≥ 3 mg/dL (≥51.3 
Pmol/L), or with evidence of hemolysis contributing to elevated total 
bilirubin, should be excluded. 
g. 
Albumin < 3.2 g/dL (<48.1 Pmol/L) 
h. 
International normalized ratio (INR) > 1.4 
5. 
Any active/clinically unstable GI (e.g., motility disorders, celiac disease, 
malabsorption syndromes), cardiovascular (e.g., hypertension and hyperlipidemia 
requiring pharmacologic treatment), endocrine (e.g., Cushing’s syndrome 
congenital 
adrenal 
hyperplasia, 
polyglandular 
endocrinopathies, 
hypo/hyperthyroidism requiring pharmacologic treatment, genetic/secondary 
causes of obesity), flaring autoimmune diseases (juvenile idiopathic arthritis, 

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adolescent lupus, juvenile dermatomyositis) or psychiatric conditions (clinically 
significant depression, ADHD, psychosis). 
Note 1: Subjects with asthma may be enrolled at the discretion of the 
Investigator if their condition is stable (i.e. no exacerbations within 4-6 
weeks prior to Randomization and no clinically meaningful changes in 
their asthma management regimens are anticipated for the duration of the 
study). 
Note 2: Subjects who are on a stable dose of anti-depressant medication(s) 
or medications(s) for ADHD for at least 6 months prior to Randomization 
and whose Investigator considers them to be psychiatrically stable may be 
enrolled.  
6. 
Known history of Inborn Errors of Metabolism and/or genetic deficiencies that 
impact amino acid metabolism or transport [e.g., urea cycle disorders, carnitine 
deficiency, carnitine palmitoyl transferase (CPT) I or II deficiency, beta-oxidation 
defects, pyruvate carboxylase deficiency, porphyria, etc.]. 
7. 
Current acute illness/health condition requiring ongoing medical treatment. 
Subjects with minor illness/injury that the investigator considers unlikely to 
significantly impact study participation or study endpoints should be discussed with 
the study Medical Monitor and/or Sponsor to determine whether the subject may 
be included, if all other eligibility criteria are met. 
8. 
Any form of diabetes other than T2DM (e.g., Type 1, MODY). 
9. 
Uncontrolled T2DM, which is defined as:   
a. 
HbA1c >9.5 % on their current T2DM regimen at Screening and must be 
stable on their usual diabetic medications for approximately 60 days prior 
to Randomization and should not be anticipating clinically significant dose 
adjustments of the T2DM medications for the anticipated duration of the 
study, and/or 
b.            Requiring >10% insulin dose adjustments within 60 days prior to Screening, 
and/or 
c. 
Requiring a complex medical regimen, e.g., needing 2 or more oral anti-
diabetics (OAD)s, and/or with a history of severe hypoglycemia on their 
OAD regimens. 
10. 
Uncontrolled hypertension (i.e. systolic blood pressure >130 mmHg and/or 
diastolic blood pressure >80 mmHg) at Screening. 
11. 
Uncontrolled hyperlipidemia (i.e. triglycerides >350 mg/dL and/or low-density 
lipoprotein (LDL) >160 mg/dL) at Screening. 
12. 
Impaired renal function (i.e. glomerular filtration rate ≤ 90 mL/min/1.73 m2) at 
Screening.  
13. 
History of bariatric surgery or planning to undergo bariatric surgery during the 
study duration (including Part 2). However, prior laparoscopic-band, intra-gastric 

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balloon, or other weight loss device which was removed >12 months prior to 
Screening is not exclusionary. 
14. 
Any contraindications to an MRI scan, including: 
a. 
Presence of non-removable ferromagnetic implants, pacemakers, aneurysm 
clips or other foreign bodies, or 
b. 
Unable to have or complete the MRI exam due to body weight exceeding 
scanner table limit or girth exceeding scanner bore diameter, or 
c. 
Clinically significant claustrophobia. Subjects experiencing mild anxiety 
due to transient claustrophobic symptoms may be treated with anxiolytics, 
if appropriate and per study site SOPs, for mitigation of those symptoms, if 
necessary. 
15. 
Known sensitivity and/or clinically significant food intolerance/allergies to proteins 
(such as whey, soy, casein, collagen, gelatin, amino acids, etc.), gluten, fats, 
carbohydrates (e.g. lactose), nuts or any ingredient in the study food product 
formulations. 
16. 
History of total parenteral nutrition (TPN) 6 months prior to Screening. 
17. 
Current or planned use of any dietary supplement intended for general metabolic 
health, weight maintenance, weight loss, OR those containing proteins, amino 
acids, ketones, or fish oils, from the time the ICF is signed through the end of the 
study.   
Note: Common examples of excluded protein, amino acid, and other dietary 
supplements include, but are not limited to: ketones, protein powders, 
shakes, bars, gels containing whey, soy, casein, collagen, amino acids, and 
their derivatives/metabolites, N-acetylcysteine, L-carnitine, etc. A few 
examples of supplements used for weight loss include green tea, green 
coffee bean extracts, garcinia cambogia, any ketogenic products, etc.  
 
18. 
Currently on or planning to be on any extreme or unbalanced diet such as 
Ketogenic, Atkins, Paleo , etc.) from the time the ICF is signed through the end of 
the study. 
19. 
Use within 2 months prior to or during Screening, or during  the study, of systemic 
glucocorticoids, any biologics (e.g., monoclonal antibodies), hormones of any kind 
(e.g., estrogens, progesterone, testosterone), valproic acid, ursodeoxycholic acid, 
any anti-obesity compounds (e.g., orlistat, locaserin, Qsymia), GLP-1 agonists, 
TZDs, or any other medications known to cause hepatic steatosis, or steatohepatitis, 
or use of any other known or potential hepatotoxins.    
20. 
Use of any other excluded medications listed in Section 6.1.1 of the protocol not 
otherwise specified in the entry criteria.    
21. 
Use of any illicit substances, including alcohol, and nicotine products 
22. 
If female, ongoing pregnancy (defined as positive serum and/or urine pregnancy 
test) and/or planned pregnancy, breast-feeding. 

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23. 
Male subjects with female partners of child-bearing potential who are unwilling or 
unable to adhere to contraception requirements. 
24. 
History of any malignancy, other than nonmelanoma skin cancer, within 4 years 
prior to Screening. 
25. 
Subjects who are currently enrolled in a clinical trial or who received an 
investigational study drug/medication, or any dietary supplement(s), food 
product(s), or participated in a lifestyle / nutritional interventional study/program 
within 60 days prior to Screening.  
26. 
Any other condition that, in the opinion of the investigator, renders or places the 
subject at risk for inclusion in the study, or that would impede compliance, or hinder 
completion of the study. 
 
4.3 
Number of Subjects Planned 
Enough subjects will be screened to have at least 30 subjects complete the study.  
Note: Subjects withdrawing early for any reason in Part 1 may be replaced. Subjects will 
not be replaced in Part 2. 
4.4 
Removal of Subjects from the Study 
A subject may be discontinued from the study at any time if the subject, the Investigator, or the 
Sponsor believes that it is not in the subject’s best interest to continue. The following is a list of 
potential reasons for discontinuation from the study: 
x Subject withdrawal of consent (or assent) 
x Subject is not compliant with study procedures 
x Subject experiences an AE that, in the opinion of the Investigator, would be in the best 
interest of the subject to discontinue  
x Treatment of a medical condition that requires use of a prohibited medication as listed in 
section 6.1. 
x Pregnancy 
x Protocol violation Lost to follow-up 
x Sponsor request for early termination of the study. 

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If a subject is withdrawn due to an AE, the subject will be followed and treated by the 
Investigator until the abnormal parameter or symptom is considered resolved, stabilized or 
unknown (e.g., lost to follow-up). 
Subjects who prematurely discontinue for any reason will be asked to return to the clinic for an 
Early Termination visit following the last active study day.  Week 13 and Week 25 study 
procedures  will be conducted at the Early Discontinuations. 
Subjects are free to withdraw from participation at any time, for any reason, specified or 
unspecified, and without prejudice. 
Reasonable attempts will be made by the Investigator to provide a reason for subject withdrawals.  
The reason for the subject’s withdrawal from the study will be specified in the subject’s source 
documents and eCRFs for early termination procedures. 
Subjects who withdraw from the study may be replaced and subjects will not be replaced in Part 
2. 
5 STUDY FOOD PRODUCT INFORMATION 
5.1 
AXA1957 Composition and Formulation Overview 
AXA1957 is a mixture of selected amino acids that are normally present in regular food and/or 
naturally produced by the body and/or readily available as dietary supplements and formulated as 
a dry powder that will be reconstituted with ~6 oz (~180 mL) of water to form an orange flavored 
drink. The composition of AXA1957 is presented in Table 6 and Table 7.  
Table 6. Amino Acid Composition of AXA1957 per Stick Pack 
Ingredients 
% 
Grams 
L-Leucine 
15% 
1.00g 
L-Isoleucine 
7% 
0.50g 
L-Arginine 
20% 
1.34g 
L-Glutamine 
10% 
0.67g 
L-Serine 
37% 
2.50g 
L-Carnitine 
5% 
0.33g 
N-Acetylcysteine 
6% 
0.43g 
Total AA  100% 6.77g 
Total BCAA  22% 
1.50g 
 
 
 
 
 

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Table 7. Excipient Composition of AXA1957  
Ingredients/Excipients 
Anhydrous Citric Acid 
Sucralose Micronized 
Xanthan Gum, Pre-Hydrated 
Artificial Vanilla Custard Flavor 
Natural Orange Flavor WONF 
FD&C Yellow No. 6 
 
5.2 
Placebo Composition and Formulation Overview 
The placebo is a well-balanced food product with a macronutrient composition of  ~53% 
carbohydrate (maltodextrin), ~22% fat (sunflower oil), and ~25% protein (collagen hydrolysate) 
that is formulated as a dry powder to be reconstituted with ~6 oz (~180 mL) of water to form an 
orange flavored drink that is color-, taste-, excipient-, and calorie-matched to AXA1957.   
5.3 
Study Food Product Preparation and Administration 
AXA1957 is composed of naturally occurring amino acids, which are normal ingredients of food 
or those readily available as dietary supplements.   
Subjects will be provided detailed Study Food Product Administration Instructions by the study 
site.  Subjects will also be provided with a 250mL Nalgene™ wide-mouth HDPE bottles with a 
screw-top lid (Thermo Scientific™ catalog #332189-0008), or similar container, that may be used 
for preparing and administering their assigned study food product.  
Study food products are provided in dry powder form in stick packs, which are then mixed in ~6 
oz (~180 mL) of water, and then consumed twice daily approximately 30 min (i.e. 30 ±5 minutes) 
before meals (e.g., before breakfast and dinner or before lunch and dinner, if breakfast is not a 
usual part of their daily routine) for the entire duration of the study.   
Note: While subjects are encouraged to consume the study food product at defined times as 
indicated above to establish a clear routine which improves adherence to study procedures, it is 
more important in this study to ensure that subjects consume their assigned products twice 
a day.  To that end, the following flexibility is allowed within the administration periods: 
x The twice daily (BID) administrations can occur at any time during the day if the two 
administrations are at least 4 hours apart, and the study food products are not consumed 
immediately before, with, or immediately after a main meal.   
x If subjects experience any clinically significant gastrointestinal (GI) discomfort while 
taking their study food product prior to meals, administrations may occur approximately 
30-60 minutes after the meal, and only after consulting with the investigator and  Medical 
Monitor or  Sponsor.  

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5.3.1 
Modification of Study Food Product Administration Amount for 
Tolerability  
Every attempt should be made to encourage subjects to stay on their assigned amount and 
regimen for the full duration of the study. However, if the study investigator determines 
any tolerability issues of clinical significance, the amount of AXA1957 or placebo may be 
reduced for an individual subject to an amount and/or regimen that was previously 
tolerated, but only after discussion with the Medical Monitor or Sponsor. For instance:  
o If the 2-stick pack twice daily amount is not tolerated, then the amount for that 
individual subject may be reduced to 1 stick pack twice daily; 
o Any subject who is not able to tolerate the study food product or placebo at any 
amount (e.g., even at 1 stick pack twice daily amount) should be discontinued from 
the study and undergo the End-of Study visit procedures.  
5.3.2 
Missed Study Food Product Administration 
If subjects miss their study food product administration before a meal then they should wait until 
the next meal to administer the product (e.g., if a subject forgets to take the study food product 
before breakfast, then wait and administer the product with lunch and dinner).   
If subjects cannot wait until the next meal (e.g., a subject forgets to administer the study food 
product before dinner and will not be eating another meal that day) they may consume the study 
food product after a meal, but must wait at least 30 minutes AFTER the meal prior to consumption 
of the food product 
5.4 
Study Food Product Packaging, Labeling and Storage 
AXA1957 and placebo will be supplied as pre-weighed powder in stick packs that will be 
reconstituted with water.  
The individual labelled stick pack units are packaged into a secondary carton, containing a total of 
42 stick packs per carton. The stick packs and exterior of the carton are labelled in accordance 
with local and national requirements, if applicable. The carton is sealed with tamper evident tape. 
The AXA1957 and placebo study food products should be stored at 15-25°C (59°F-77°F) ambient 
temperature. The products are shipped at ambient temperature. 

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5.5 
Method of Assigning Study Food Product to Subjects 
Subjects will be screened sequentially and assigned a 5-digit subject number (3-digit site #- 2-digit 
subject #), as noted in the example below: 
Site #100: 100-01, 100-02, 100-03 … 
Site #200: 200-01, 200-02, 200-03 … 
If a subject is re-screened they will need to be re-consented and a new subject number will be 
assigned the based on the numbering convention listed above. 
5.6 
Accountability, Disposal, Return, or Retention of Unused Study Food Product 
The site staff and/or pharmacist will document receipt of study food product from the Sponsor or 
its designee and preparation of the product for administration to subjects.  Product administration 
and returns will be documented on study food product accountability log(s). The site should 
maintain all unused product containers (cartons and stick packs) until final review of accountability 
is conducted by the study monitor, and instructions regarding return or disposal, as applicable, are 
provided. 
5.7 
Compliance with Study Food Product Administration 
Subjects will be asked to return the cartons and any remaining stick packs at each visit.  
Compliance will be assessed by reviewing the number of returned stick packs, if any, at each visit. 
Any apparent discrepancies between quantity of stick packs returned and the number anticipated 
based on the administration schedule will be discussed with the subject to ensure an understanding 
of the administration instructions. Subjects will also record the amount of the product consumed 
in a daily administration diary. Repeated non-compliance with administration instructions may 
necessitate discontinuation from the study, based on the Investigator’s and/or Sponsor’s judgment. 
6 CONCOMITANT THERAPIES AND OTHER RESTRICTIONS 
6.1 
Concomitant Therapy 
Any medication or vaccine (including over-the-counter or prescription medicines, vitamins, and/or 
herbal supplements) that the patient is receiving at the time of enrollment or receives during the 
study must be recorded along with: 
x Reason for use 
x Dates of administration including start and end dates 
x Dosage information including dose and frequency. 
If significant changes in antidiabetic medications are required during the study, the Investigator 
should discuss with study Medical Monitor and Sponsor whether the subjects should continue in 
the study or be withdrawn. 

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6.1.1 
Concomitant Use of the Following is Prohibited During the Study: 
x All prandial insulins (e.g. Lispro, Aspart, Glulisine, Regular, Humulin R, etc.) 
Note:  Use of insulin mixtures (e.g. 70/30), Humulin N, NPH insulin, or other basal 
insulins (e.g. detemir, glargine, concentrated insulins such as U500 etc.) are 
permitted only if they are at stable doses and regimen for approximately 60 days 
prior to Screening, and no clinically significant dose adjustments in these insulin 
regimens are anticipated during the study duration. Minor adjustments as per the 
standard of care are permitted. 
x Systemic glucocorticoids 
x Amiodarone (even if it was used ≥2 months prior to Screening)  
x Methotrexate 
x Tetracyclines 
x Tamoxifen 
x Hormone-based contraception products of any kind and in any form (such as 
progesterone and/or estrogen containing pills, patches, creams, depots, implants, 
injections, devices, etc.), as well as any products or supplements containing estrogen, 
progesterone, or related products 
x Any type of testosterone preparations (e.g., patches, gels, pills, depots, injections), 
including anabolic steroids 
x Valproic acid 
x Obeticholic acid (OCA) 
x Ursodeoxycholic acid (Ursodiol® and Urso®) 
x Anti-obesity medications and dietary supplements for weight loss (e.g., orlistat, locaserin, 
Qsymia, green tea extract, green coffee bean extract, garcinia cambogia, any ketogenic 
products, etc.) 
x Dietary supplements containing ketones, fish oils, protein, and amino acids including, but 
not limited to: protein powders, shakes, bars, and gels containing whey, soy, collagen, 
gelatin, casein, amino acids or their derivatives/metabolites such as N-acetylcysteine, L-
carnitine, and any ketogenic products.   
x Vitamin E >400 IU/day 
x GLP-1 analogs (e.g., exenatide, Byetta) or GLP-1 receptor agonists (e.g., liraglutide, 
dulaglutide, semaglutide, etc.) 
x TZDs (e.g., pioglitazone, rosiglitazone) 

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x Other known hepatotoxins (acetaminophen is permitted as long as the dose is <600 
mg/day) 
x Any other investigational product. 
The study Medical Monitor should be contacted if there are any questions regarding concomitant 
or prior therapy. The Medical Monitor, in consultation with the Study Sponsor, will make the 
final determination of which subjects are enrolled in the study and if a supplement is permitted to 
be initiated during the study (for example, vitamin D supplements will be permitted to treat 
laboratory-confirmed vitamin D deficiency).     
7 STUDY ASSESSMENTS AND PROCEDURES 
The schedule of assessments is summarized in Table 1. A description of study procedures and 
assessments is provided below.   
7.1 
Baseline and Disease Characteristics  
Details regarding medical history will be collected during Screening.  Prior and concomitant 
medications will also be recorded during this time.  
7.2 
Physical Examination, Vital Signs and Body Weight   
Screening and Day 1/Baseline physical examination (PE) will consist of an assessment of general 
appearance, skin, thorax/lungs, abdomen, lymph nodes, head, ears, eyes, nose throat, neck, and 
cardiovascular, musculoskeletal, and neurological systems.  Subsequent PE examinations will be 
abbreviated and will consist of general appearance, skin, thorax/lungs, cardiovascular system, and 
abdomen.   
Physical examination findings will be documented in the subject’s source documents.  Any new 
PE finding that represents a new abnormal finding or a worsening from Baseline condition will be 
recorded as an AE. Vital sign measurements include blood pressure, pulse, body temperature, and 
body weight and will be measured at every study visit.  Vital signs should be conducted after 
subjects have been sitting quietly in a resting position for at least 5 minutes.  If needed, blood 
pressure at screening may be re-tested two additional times at >15-minute increments to confirm 
eligibility.  
7.3  
 
12-Lead Electrocardiogram 
An ECG will be performed locally using validated machinery available locally to each clinical 
site.  The ECG reports will be reviewed by the Investigator or qualified sub-Investigator and 
assessed as (i) normal, (ii) abnormal – not clinically significant, or (iii) abnormal   clinically 
significant.  

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7.4 
Lifestyle Guidance  
During each study visit, subjects will meet with a study dietician or other qualified study staff who 
will reinforce the lifestyle recommendations in Appendix 1 to subjects and their caregivers. In 
between the study visits, subjects may receive phone calls approximately once a week where 
qualified study staff may continue to reinforce these lifestyle recommendations.   
7.5 
Multiparametric MRI  
Subjects will undergo multiparametric MRI examination up to four times during the study to 
characterize and quantify liver tissue (e.g., liver fat/ inflammation) and body composition such as 
lean mass and fat mass. Some imaging centers may also offer the option to assess heart function. 
Multiparametric MR imaging will be conducted at the indicated time points in Table 1. The 
screening MRI scan should be performed only after all other eligibility criteria have been met and 
should occur approximately within 7 days prior to potential randomization.  Scans should be 
scheduled based on scanner availability which may not correlate with the same day as the study 
clinic visit.  MRIs at Visit 7 and 13 are not required to occur the same day as the study clinic visit, 
but must occur within the +/- 5 day visit window. Every attempt should be made to schedule scans 
at roughly the same time of the day to reduce diurnal fluctuation in daily liver lipid levels. . 
Subjects are required to be fasting for at least 4 hours prior to all MRI scans.  Consequently, on 
the MRI scanning days, subjects may adjust their placebo or AXA1957 administration regimens 
accordingly.  
Details of the multiparametric MRI assessments will be described in the Imaging Review Charter 
and Imaging Manuals.   
7.6 
Fibroscan or Right Upper Quadrant Ultrasound Assessment 
A Fibroscan assessment measuring hepatic steatosis (via controlled attenuation parameter, CAP),  
or right upper quadrant ultrasound assessing sonographic features of hepatic steatosis, may be used  
to determine subject eligibility and to triage for the multiparametric MRI assessment provided it 
was obtained within 90 days of the Randomization.  
7.7 
Clinical Laboratory Assessments 
Blood samples for clinical laboratory evaluations are listed in Table 8 below.  Detailed blood 
collection procedure for will be described in the Laboratory Manual A retain sample of plasma 
will be collected at each biomarker timepoint for possible future non-genetic exploratory analysis.   
Samples will be analyzed at central and specialty laboratories.  Laboratory reports will be reviewed 
by the Investigator or designee and filed in the source document.  Clinical laboratory findings that 
represent a worsening from a baseline value and are considered by the Investigator to be clinically 
significant will be recorded as an AE. 

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Subjects will be required to fast for approximately 8 hours prior to reporting to the study site for 
specific blood draws as indicated in Table 1.   
Placement of a peripheral IV catheter for blood draws may be considered as per investigator 
discretion in accordance with institutional policies. If utilized, saline lock is recommended. In 
addition, care should be taken to ensure proper waste is drawn with blood collection and considered 
in the estimated blood volume collected during the study.  
Topical anesthetics may also be used at the Investigator’s discretion and/or the institution’s 
policies.  

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Table 8. Laboratory Assessments 
Chemistry 
(fasted) 
Haematology 
(CBC) 
Haematology 
(CBC) 
Lipid panel 
(fasted) 
Metabolites 
(fasted) 
Metabolic 
Panel (fasted) 
Biomarkers 
(fasted) 
Biomarkers 
(fasted) 
Other 
x Albumin 
x Alkaline 
phosphatase 
(ALP) 
x ALT 
x AST 
x Blood urea 
nitrogen 
(BUN) 
x Calcium 
x Chloride 
x Creatinine 
x Gamma-
glutamyl 
transferase 
(GGT) 
x Glucose 
x Phosphorus 
x Potassium 
x Sodium 
x Total Bilirubin 
x Total CO2 
(measured as 
bicarbonate) 
x Total protein 
x Uric acid 
x eGFR 
 
x Hematocrit 
x Hemoglobin 
x Mean 
corpuscular 
hemoglobin 
(MCH) 
x Mean 
corpuscular 
hemoglobin 
concentration 
(MCHC) 
x Mean 
corpuscular 
volume 
(MCV) 
x Platelet count  
x Red blood cell 
count 
 
x White blood 
cell (WBC) 
count 
x WBC 
differential 
(% & absolute) 
x Basophils 
x Eosinophils 
x Lymphocytes 
x Monocytes 
x Neutrophils 
x PBMC 
isolation 
x Coagulation 
(INR, PT/PTT) 
x Total 
cholesterol 
x High-density 
lipoprotein 
cholesterol 
(HDL-C) 
x Low-density 
lipoprotein 
(LDL-C) 
x Triglycerides 
x Non-HDL-C 
 
x Lactate 
x Glycerol 
x Pyruvate 
x Insulin 
x Beta-
hydroxybutyrat
e (BHB) 
x Non-esterified 
fatty acids 
(NEFA) 
x Free amino 
acids  
x Hemoglobin 
A1c (HbA1c) 
x Fructosamine 
x Homeostasis 
model 
assessment of 
insulin 
resistance 
(HOMA-IR; 
calculated) 
x Adipose tissue 
insulin 
resistance 
(Adipo-IR; 
calculated)  
x Total 
Testosterone 
(T) 
x Dehydro-
epiandrosterone 
(DHEA)  
x Estradiol (E2) 
 
x Adiponectin 
x FGF-21 
x IL-1beta 
x High 
sensitivity C-
reactive 
protein 
(hsCRP) 
x MCP-1 
x CK-18 (M30 
and M65) 
x YKL-40 
x Alpha-2 
macroglobulin,  
x Enhanced liver 
fibrosis (ELF) 
Score (TIMP-
1, PIIINP & 
hyaluronic 
acid) 
x Apolipoprotein 
B (ApoB) 
x Apolipoprotein 
CIII (Apo-
CIII) 
x Lipoprotein a 
[Lp(a)] 
x OWL 
lipidomic 
panel 
x N-terminal 
fragment of 
type III 
collagen 
(ProC3) 
x Internal 
epitope in 
the 7S 
domain of 
type IV 
collagen 
(ProC4) 
x Released N-
terminal 
pro-peptide 
of type VI 
collagen 
(ProC6) 
x Internal 
epitope in 
the N-
terminal 
pro-peptide 
of type 1 
collagen 
(P1NP) 
 
 
 
Serum 
Pregnancy 
Test at 
Screening; 
Urine 
Pregnancy 
test all 
other days.   
 

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Urinalysis 
(quantitative) 
x pH 
x Specific gravity 
x Protein 
x Glucose 
x Ketones 
x Bilirubin 
x Blood 
x Nitrate 
x Urobilinogen 
x Leukocyte esterase 
x Urine urea nitrogen 
 
 
 

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7.8 
Plasma Amino Acid Concentration Sampling 
On Visit 1, Visit 6, and Visit 10, all subjects (including those on placebo) will be instructed to 
arrive at the study site after approximately 8 hours of overnight fast.  They will have a fasted blood 
draw (T=0), will be administered their assigned study food product at the study site, and then 
approximately T=1-2 hours later, another blood sample will be collected for plasma amino acid 
concentrations. The exact clock times of the T=0 (pre-administration) and T=1-2hr (post-
administration) samples should be recorded in the source documents.   
Samples will be analyzed for administered amino acids (L-Leucine, L-Isoleucine, L-Arginine, L-
Glutamine, L-Serine, L-Carnitine, Acetylcysteine) and other amino acids as appropriate).  Detail 
will be described in the PK Analytical Plan.  
7.9 
Food and Activity Diaries & Dietary Guidance 
7.9.1 
Study Dietary and Exercise Guidance 
Diet and exercise regimens play an important role in subjects with NAFLD and can possibly 
impact study outcome measures.  In order to control for this variable, all enrolled  subjects will be 
provided Guidance and Lifestyle Recommendations for Adolescents with NAFLD by qualified 
site staff (See Appendix 1).  All sites will provide the uniform guidance to ensure that subjects are 
receiving consistent diet and exercise instructions across different sites.  The Sponsor will provide 
instructions to study sites on how to provide the guidance to enrolled subjects.  Qualified site staff 
will provide the guidance and answer any questions  subjects and/or family have during all visits 
starting at Visit 1.  During weeks where there are no study visits, the qualified site staff will call 
subjects to reinforce the guidance and address questions.   
7.9.2 
Four Day Diet and Exercise Diary 
Subjects (with the help of their family) will be asked to complete a diet and exercise diary over a 
4- day period which should include 2 weekdays and 2 weekend days prior to Visit 1.  Subjects will 
carefully record all foods/beverages they eat/drink on a daily basis, and their usual physical activity 
routines to establish a baseline lifestyle pattern.  Subjects should not alter their normal routines or 
diets during this time.  The intent of the diary is to capture diet and exercise regimens over four 
typical days in their lives.  
7.9.3 
National Institute for Health and Care Excellence Quality Standard 
Life Style Questions 
Each week subjects will be provided with a standardized questionnaire asking “yes or no” 
questions if they are adhering to the study diet and exercise guidance over a seven-day period.  The 
questionnaire has approximately 10 questions and may be filled out at home or at the study site.  
Subjects will be told to answer the questions honestly, and that they will not be punished or 
rewarded based on how they answer the questions.  The questionnaire will serve as a tool for the 
site staff on areas of the study diet and exercise guidance to focus instruction on during the visit. 

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7.10 
Hunger and Satiety Visual Analog Scale (VAS) 
In the week prior to the Day 1 visit, subjects will be asked to complete the hunger and satiety VAS 
to get them familiarized with the VAS self-assessment. Subjects will be asked several questions 
about hunger and fullness (satiety) and activity by marking on a scale associated with each 
question. Each of the questions in the VAS includes a scale that is 100 mm long.  The study staff 
will measure the distance (in mm) from the left to right side of the scale, to the line that the subject 
marked as their answer.  This length (in mm) is the score for that question.  
The VAS assessment will be conducted biweekly during the administration period of Part 1 and 
Part 2.  During each 2 week period subjects will choose a day to complete the VAS.  For 
consistency, subjects should be instructed to try to complete the VAS on the same day of the week 
throughout the study. On the days the VAS is completed subjects will fill-out the VAS worksheets 
in conjunction with each study food product administration for that day (e.g., morning and 
evening) at two timepoints:  1) immediately prior to the study food product administration; and 2) 
immediately prior to eating the meal where the study food product is administered (see Figure 3).    
Subjects must return completed VAS worksheets for review at each study visit.    
Figure 2: Timing of Visual Analog Scale Completion  
 
7.11 
Study Food Product Administration Diary 
Subjects will be provided a diary to record study food product administration.  Subjects will be 
required to complete the diary daily and return the diary to the clinic during each study visit for 
the site staff to review. 
 
Study product 
administration
t=0
t=0
Meal #1
Meal #2
t=30 mins
Study product 
administration
t=0
Meal #2
t=30 mins

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8 ADVERSE EVENTS AND SAFETY REPORTING 
The Investigator is responsible for the detection and documentation of events meeting the criteria 
and definition of an AE or SAE as provided in this protocol.  
8.1 
Definitions 
8.1.1 
Adverse Events 
An AE is any untoward medical occurrence associated with the use of a study food product or with 
study participation, regardless of the relationship of the occurrence to study food product or 
protocol. An AE can be any unfavorable and unintended sign (including an abnormal laboratory 
finding), symptom or disease temporally associated with the use of the product, whether or not 
considered related to the product. An AE can arise from any use of the product, and from any route 
of administration, formulation or dose, including an overdose. 
From the time of informed consent up to first administration of study food product on Day 1, any 
untoward medical occurrence considered related to study procedures will be recorded as an AE. 
Adverse events that occur from the first administration of study food product through the Follow-
up Visit will be considered treatment-emergent AEs. 
For each AE, start date, stop date, causality (relationship to study food product), action taken, 
outcome, and severity will be recorded in the source document and on the case report form (CRF). 
8.1.2 
Adverse Reaction and Suspected Adverse Reaction  
All noxious and unintended responses to the study food product related to any amount 
administered should be considered adverse reactions. Suspected adverse reactions are any AEs for 
which there is a reasonable possibility that the product caused the AE.  
AEs associated with the use of study food product outside what is described in the protocol, 
including misuse and abuse of the product, are considered adverse reactions. 
8.1.3 
Serious Adverse Event Definition  
An SAE is any untoward medical occurrence at any dose that results in one or more of the 
following: 
x 
Results in death 
x 
Is life-threatening (at risk of death at the time of the event) 
x 
Requires subject hospitalization or prolongation of existing hospitalization  
NOTE: Complications that occur during hospitalization are AEs. If a complication 
prolongs hospitalization or fulfills any other serious criteria, the event is serious. 
Hospitalization for elective treatment of a pre-existing condition that did not worsen from 
baseline is not considered to be an AE. 

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x 
Results in disability/incapacity 
NOTE: The term disability is defined as a substantial disruption of a person’s ability to 
conduct normal life functions. This definition is not intended to include experiences of 
relatively minor medical significance, such as uncomplicated headache, nausea, vomiting, 
diarrhea, influenza, or accidental trauma (i.e., sprained ankle) that may interfere or prevent 
everyday life functions but do not constitute a substantial disruption. 
x 
Is a congenital anomaly/birth defect. 
x 
Important medical events that may not result in death, be life-threatening, or require 
hospitalization, may be considered an SAE when, based upon appropriate medical 
judgment, may jeopardize the subject and may require medical or surgical intervention to 
prevent one of the outcomes listed in this definition. 
All SAEs must be reported to the Sponsor or designee within 24 hours of the site’s awareness of 
the event.  All available information should be included in the initial report. Additional follow-up 
information should also be reported within 24 hours.  
8.1.4 
Causal Relationship Assessment 
The Investigator is required to provide an assessment of relationship of AEs and SAEs to study 
food product or protocol procedures, if applicable. To promote consistency, the following 
guidelines should be taken into consideration, along with good clinical and scientific judgement, 
when determining the relationship of AEs to study food products: 
Definitely related: 
A clinical event, including laboratory test abnormality, occurring in a 
plausible time relationship to the study food product administration, and 
which cannot be explained by concurrent disease or other drugs or 
chemicals.  The response to withdrawal of the study food product should be 
clinically plausible.   
 Possibly related: 
A clinical event, including laboratory test abnormality, with a reasonable 
time sequence to the study food product administration, but which could 
also be explained by concurrent disease or other drugs or chemicals.  
Information on the withdrawal of the study food product may be lacking or 
unclear.  
Unlikely related: 
A clinical event, including laboratory test abnormality, with little or no 
temporal relationship to the study food product administration, and which 
other drugs or chemicals or underlying disease provide plausible 
explanations.  
 
8.2 
Categorization of Adverse Events 
The intensity of an AE will be categorized as follows:   
Mild:   
Mild events are those which are easily tolerated with no disruption 
of normal daily activity.  

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Moderate:   
Moderate events are those which cause sufficient discomfort to 
interfere with daily activity.  
Severe:   
Severe events are those which incapacitate and prevent usual 
activity.   
8.3 
Recording and Reporting of All Non-Serious and Serious Adverse Events 
Subjects will be required to report any AE that occur after informed consent is signed. 
All AEs will be recorded from the time of informed consent until the last follow-up visit/call. 
Subjects will be instructed to report all AEs and will be asked a general health status question at 
each study visit. 
An AE should be followed until it is either resolved, has returned to baseline, or is determined to 
be a stable or chronic condition.  
If a non-serious AE is ongoing at the follow-up visit/call, the AE will be recorded as ongoing. AEs 
that are ongoing at the follow-up visit will be followed to resolution at the discretion of the 
Investigator.  
At each study visit, all AEs that have occurred since the previous visit must be recorded. The 
Investigator or appropriate designee must determine the intensity of the AE. 
Where possible, a diagnosis rather than a list of symptoms should be recorded. If a diagnosis has 
not been made, then each symptom should be listed individually, with severity (mild, moderate, 
or severe). 
All study food product-related AEs/SAEs will be followed to resolution (the subject’s health has 
returned to his/her baseline status or all variables have returned to normal), or until an outcome is 
reached, stabilization occurs (the Investigator does not expect any further improvement or 
worsening of the event), or the event is otherwise explained, regardless of whether the subject is 
still participating in the study. Where appropriate, medical tests and examinations will be 
performed to document resolution of the event(s). 
8.4 
Serious Adverse Event Reporting Procedures 
All SAEs, from the signing of informed consent through the last follow-up visit, will be reported 
to the Sponsor or its representative, within 24 hours of the Investigator’s first knowledge of the 
event, even if the event does not appear to be related to the study food product or the protocol.  

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The initial SAE report must be as complete as possible, including details of the current illness and 
(serious) AE, and an assessment of the causal relationship between the event and the food product. 
Information not available at the time of the initial report (e.g., an end date for the event, laboratory 
values received after the initial report, or hospital discharge summary) must be documented on a 
follow-up report. All follow-up information must be reported in the same timelines as the initial 
report.  
At any time after completion of the AE reporting period, if an Investigator becomes aware of an 
SAE that is suspected by the Investigator to be related to the study food product, the event must 
be reported to the Sponsor or its representative.  
The following information is a minimum set of information required for all initial SAE reports: 
x Investigator name 
x Subject identifiers 
x AE term(s) 
x Suspect study food product 
x Study product event relationship 
x Reason why the event is serious. 
SAEs will be entered in the electronic data capture (EDC) system; the project contact for SAE 
receipt will be notified via the EDC system upon entry of an SAE in the system.  In circumstances 
where the EDC system is not available, notification by telephone is acceptable. For telephone 
reports, the SAE must be entered into the EDC system as soon as the system is available for data 
entry.  
The site will notify the Sponsor or its representative of additional information or follow-up to an 
initial SAE Report as soon as relevant information is available and within 24 hours of awareness. 
Follow-up information is reported in the EDC system. 
8.4.1 
Safety/SAE Reporting Contact Information 
The preferred means of SAE reporting is via the EDC system, reference the Case Report 
Completion Guidelines for instructions. Instructions for initial SAE reporting and urgent safety 
issues/questions will be provided in the Safety Manual provided to the sites.   
8.5 
Data and Safety Monitoring Committee 
There will not be an independent Data and Safety Monitoring Committee established for this study.  
The Investigators, Medical monitor and Sponsor will monitor all data for safety and protection of 
subjects. 
 
 

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8.6 
Reporting to IRBs and Ethics Committees 
The Sponsor or its designee is responsible for notifying the investigational sites of all expedited 
SAEs.  
The Investigator will notify institutional review boards (IRBs) or Ethics Committees (ECs) of 
serious, related AE(s) or significant risks to subjects, per local country requirements. The 
Investigator must keep copies of all AE information, including correspondence with the Sponsor, 
IRBs and ECs on file. It is the responsibility of the Principal Investigator to notify the IRB/EC of 
all SAEs that occur at his or her site.  
8.7 
Contraception and Pregnancy 
No human studies of the effects of AXA1957 on conception, pregnancy, or lactation have been 
performed to date.  Therefore, female participants should not be exposed to the product if pregnant, 
breastfeeding, or attempting to conceive. Although there are no known or anticipated risks of 
potential harm to a foetus, there are currently no data to definitively prove whether a foetus would 
be at risk with this specific dietary supplement. Therefore, all female participants in this study will 
be asked to abstain from sexual intercourse during their participation in the study (including those 
that are not sexually active).  During screening, the study site should allow for a private 
conversation with  all potential female subjects to inquire if they are currently sexually active, or 
think it is likely/plan to be sexually active during the next 5- to 8-months (i.e. from first day of 
screening to last day of follow up, which is a mandatory 19 weeks in Part 1, and up to 31 weeks in 
the optional Part 2), and  advise them of the study expectations as described below. 
The following guidelines for contraception must be followed during the study: 
x Heterosexually active female participants of childbearing potential (i.e. post-pubertal 
and /or post-menarchal, not surgically sterile [defined as tubal ligation, hysterectomy, 
or bilateral oophorectomy]) must agree to abstain from sexual intercourse for the entire 
duration of the study (i.e., from time ICF is signed to end-of-study follow up). 
 
x Abstinence for the purpose of the study is defined as abstaining from sexual intercourse 
for from the time the ICF is signed until discharge from the study. Periodic abstinence 
(e.g., calendar, ovulation, symptothermal, etc. methods) are NOT acceptable. 
 
x Hormonal contraception methods are considered prohibited medications and not 
allowed in the study as oestrogen can impact liver fat. As this study measures liver fat, 
this could potentially confound the study data and results.   
 
x Sexual activity must be ascertained at each study visit, and every female participant in 
the study must complete a required pregnancy test at each study visit.  
 

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Male subjects with female partners of child-bearing potential must use at least 1 of the following 
contraceptive methods: complete abstinence, or barrier method of contraception.  The 
contraception requirements must be followed from Screening (i.e. day the informed consent is 
signed) to last day of follow-up.  
Pregnancy of a female partner of a male study participant must be reported to the Investigator, and, 
in turn, the pregnancy must be reported to the Sponsor or its representative within 24 hours of the 
Investigator’s awareness of the pregnancy. 
In the case of pregnancy of a female study participant during the study, study food product should 
be discontinued, and the Sponsor informed immediately.  Follow-up of the pregnancy will occur 
until the outcome is available, including premature termination.  The follow-up period will be 
deemed to have ended when the health status of the child has been determined upon birth.  
9 STATISTICAL ANALYSIS  
A detailed statistical analysis plan describing the specific analyses to be performed for this study 
will be completed prior to database lock.  All analyses will be performed, and all tables, figures, 
and data listings will be prepared using SAS version 9.4 or higher.  Summary statistics for 
continuous variables will include the mean, standard deviation, median, minimum and maximum 
value; categorical variables will be presented as counts and percentages.   Some subgroup analyses 
(such as liver fat or ALT assessments) may be within each of the gender groups given the known 
and well-established gender differences in these parameters. 
9.1 
Sample Size 
As this is food product study, no formal sample size calculations will be conducted.  A sufficient 
number of subjects will be screened to have  approximately thirty (30) subjects in total complete 
the study.  This study is exploratory in nature, and the sample size is based on clinical judgement 
that this number of subjects will be sufficient to provide a characterization of the product safety.   
Randomization will be stratified by gender with a block size of  three (3). Randomization will 
occur via an interactive web response system (IWRS). 
9.2 
Analysis Sets 
The Safety analysis set will include all subjects who receive at least 1 administration of either 
placebo or AXA1957.  Any subject who is screened but who does not receive study food product 
will not be included in study reporting. 
The Per protocol (PP) analysis set will include all subjects who receive at least 1 administration of 
AXA1957 or placebo with no major protocol deviations. 
9.2.1 
Safety Analyses 
Safety analyses will be performed using the Safety analysis set.  Safety and tolerability will be 
evaluated using descriptive statistics and listings of AEs, physical examination, including body 

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composition (lean and visceral fat mass) changes, clinical laboratory test values, including plasma 
amino acid levels, vital signs, weight, body temperature, ECGs and other safety parameters. 
Analyses of AEs will be performed for those events that are considered product-emergent, where 
product emergent is defined as any AE with onset (or any changes in a pre-existing condition) after 
the first administration of either placebo or AXA1957.  All efforts will be made to record start and 
stop dates for AEs.  Adverse events with partial dates will be assessed using the available date 
information to determine product-emergent status. Adverse events with completely missing dates 
will be assumed to be product-emergent. 
Adverse event verbatim terms will be coded to preferred terms using the Medical Dictionary for 
Regulatory Activities (MedDRA) dictionary.  AEs will be summarized by administration group 
using subject incidence rates.  Therefore, in any tabulation, a subject contributes only once to the 
count for a given AE (preferred term).  Separate tabulations will be produced for all product-
emergent AEs, product-related AEs (those considered by the Investigator as possibly study food 
product related), SAEs, and discontinuations due to AEs.  By subject listings will be provided for 
any deaths, SAEs, and AEs leading to discontinuation of study food product administration.  If the 
number of AEs seen on the study is very small, listings only will be produced. 
Clinical safety laboratory test values will be presented using conventional units.  Listings of these 
data will be presented with out-or-normal range values flagged.  Mean, standard deviation, median, 
min, and max will be calculated at each time point.  Vital signs values will be presented in 
listings.  Mean, standard deviation, median, min, and max will be calculated at each time point.   
ECG values will be presented in listings.  A shift table to indicate change in result (normal, 
abnormal – not clinically significant, or abnormal, clinically significant).  
9.3 
Interim Analysis 
Interim analyses in addition to the final analysis are planned for this study. Up to two interim 
analyses are planned in Part 1.  One after approximately 50% of subjects complete Visit 4 (Week 
7) and another after approximately 50% subjects complete Visit 6 (Week 13). 
9.4 
Pharmacokinetics 
Based on sparse plasma amino acid concentration sampling at two time points on Day 1, Week 13, 
and Week 25 (for those in Part 2), sparse population PK analysis may be performed to estimate 
PK parameters (Cmax, AUC, Tmax, etc.) as appropriate. 
Details of PK computation (e.g., data-handling process) will be outlined in PK Analytical Plan 
(PKAP). 

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10 ETHICS AND ADMINISTRATIVE DETAILS 
10.1 
Ethics 
This study is to be performed in accordance with the protocol, the Declaration of Helsinki, the 
International Council for Harmonization (ICH) Harmonized Tripartite Guideline for Good Clinical 
Practice (GCP), and all applicable local regulations. 
To maintain confidentiality, all laboratory specimens, evaluation forms, reports and other records 
will be identified by a coded number and initials only. All study records will be kept in a locked 
file cabinet. Clinical information will not be released without written permission of the subject, 
except as necessary for monitoring by health authorities. The Investigator must also comply with 
all applicable privacy regulations. 
The protocol, consent form(s), diaries and any advertising materials along with any amendments 
will be reviewed and approved by an IRB/EC prior to study initiation. Serious adverse experiences 
regardless of causality will be reported to the IRB/EC in accordance with the standard operating 
procedures and policies of the IRB/EC, and the Investigator will keep the IRB/EC informed as to 
the progress of the study. The Investigator will obtain assurance of IRB/EC compliance with 
regulations. 
Any documents that the IRB/EC may need to fulfill its responsibilities (such as protocol, protocol 
amendments, consent forms, information concerning subject recruitment, payment or 
compensation procedures, or other pertinent information) will be submitted to the IRB/EC. The 
IRB/EC’s written unconditional approval of the study protocol and the informed consent form will 
be in the possession of the Investigator before the study is initiated. The IRB/EC’s unconditional 
approval statement will be transmitted by the Investigator to the Sponsor or designee prior to the 
shipment of study supplies to the site. This approval must refer to the study by exact protocol title 
and number and should identify the documents reviewed and the date of review. 
Protocol and/or informed consent modifications or changes may not be initiated without prior 
written IRB/EC approval except when necessary to eliminate immediate hazards to the subjects or 
when the change(s) involves only logistical or administrative aspects of the study.  Such 
modifications will be submitted to the IRB/EC and written verification that the modification was 
submitted and subsequently approved should be obtained.   
The IRB/EC must be informed of revisions to other documents originally submitted for review; 
serious and/or unexpected adverse experiences occurring during the study in accordance with the 
standard operating procedures and policies of the IRB/EC; new information that may affect 
adversely the safety of the subjects of the conduct of the study; an annual update and/or request 
for re-approval; and when the study has been completed. 

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All study findings and documents will be regarded as confidential. Subject confidentiality will be 
strictly maintained to the extent possible under law. Subjects will be identified in the research 
records, case report forms, and other documents submitted to the Sponsor or its designated 
representative, by their assigned subject number. Documents that identify the subject (e.g., the 
signed informed consent form) should not be submitted to the Sponsor or its designated 
representative and must be maintained in confidence by the Investigator. 
10.2 
Informed Consent/Patient Information Sheet 
Informed consent and assent, when required, will be obtained in accordance with the Declaration 
of Helsinki, ICH GCP, the EU Data Protection Directive 95/46/EC and local regulations. 
The Investigator will prepare the site-specific informed consent/assent form and provide the 
documents to the Sponsor or designee for approval prior to submission to the IRB/EC. The consent 
form(s) generated by the Investigator must be acceptable to the Sponsor and be approved by the 
IRB/EC. The written consent document(s) will embody the elements of informed consent and/or 
assent as described in the current ICH GCP E6 guideline and will also comply with local 
regulations. The Investigator will send an IRB/EC-approved copy of the informed consent form(s) 
to the Sponsor or designee for the study file. 
Properly executed, written, informed consent(s) will be obtained from each subject, parent or legal 
guardian as deemed necessary, prior to entering the subject into the trial. Information should be 
given in both oral and written form and subjects (or their parent (s)/legal representatives) must be 
given ample opportunity to inquire about details of the study. If a subject is unable to sign the 
informed consent form, a legal representative may sign for the subject. A copy of the signed 
consent form(s) will be given to the subject, parent and/or legal representative of the subject and 
the original will be maintained with the subject’s records. 
10.3 
Administrative Details 
10.3.1 
Monitoring 
The Sponsor or its representative (e.g., clinical research associate) may conduct a clinic visit to 
verify the qualifications of each Investigator, inspect the clinic’s facilities, and inform the 
Investigator of responsibilities and procedures for ensuring adequate and correct study conduct 
and documentation. 
Throughout the study, the monitor will make scheduled and possibly unscheduled clinic visits to 
discuss the progress of the study with the Investigator or his/her representatives, review the 
informed consent forms, review the CRFs for completeness and accuracy, review protocol 
compliance, compare CRFs and individual subject’s medical records and source documentation, 
assess product accountability, and ensure that the study is being conducted according to pertinent 
regulations and GCP. The review of medical records will be performed in a manner to ensure that 
subject confidentiality is maintained. 

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Monitoring visits will be conducted by the Sponsor or its representatives according to ICH GCP 
(E6). By signing this protocol, the Investigator grants permission to the Sponsor or designee, and 
appropriate authorities, to conduct on-site monitoring and/or auditing of all appropriate study 
documentation. 
10.3.2 
Recording, Access and Retention of Source Data 
The Investigator must make study data and documentation accessible to the monitor, and other 
authorized representatives of the Sponsor (or designee) and IRB/ECs upon request. 
A file for each subject must be maintained that includes the signed informed consent form/assent 
form and copies of all source documentation related to that subject. The Investigator must ensure 
the reliability, integrity and availability of source documents from which the information on the 
CRF was derived. 
All study documents (subject files, signed informed consent/assent forms, copies of CRFs, 
Investigator Site File, etc.) must be kept secured for a period of 7 years following the completion 
of the study unless there is prior written agreement with the Sponsor. There may be other 
circumstances for which the Sponsor is required to maintain study records and, therefore, the 
Sponsor should be contacted prior to removing study records for any reason. 
10.3.3 
Study Termination 
If the Sponsor or Investigator discovers conditions arising during the study that suggest the study 
should be halted, then this can happen only after appropriate consultation between the Sponsor and 
Investigator. Conditions that may warrant study termination include, but are not limited to: 
x The discovery of any unexpected, significant, or unacceptable risk to the subjects enrolled 
in the study. 
x Failure of the Investigator to enter subjects at an acceptable rate. 
x Unsatisfactory subject enrollment with respect to quality and/or quantity or data recording 
is inaccurate and/or incomplete on a chronic basis. 
x Insufficient adherence to the protocol requirements. 
x A decision on the part of the Sponsor to suspend or discontinue development of study food 
product. 
10.3.4 
Protocol Violations 
A protocol violation occurs when the subject, Investigator or Sponsor fails to adhere to significant 
protocol requirements affecting the inclusion, exclusion, subject safety and primary endpoint 
criteria. Protocol violations for this study include, but are not limited to, the following: 
x Failure to meet inclusion/exclusion criteria 

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x Use of a prohibited concomitant medication 
x Failure to comply with GCP guidelines will also result in a protocol violation. The Sponsor 
will determine if a protocol violation will result in withdrawal of a subject. 
When a protocol violation occurs, it will be recorded and reviewed with the Investigator.  
10.3.5 
Data Quality Assurance 
The Investigator will prepare and maintain adequate and accurate source documents designed to 
record all observations and other pertinent data for each subject treated with the study food product. 
Study personnel at each site will enter data from source documents corresponding to a subject’s 
visit into the protocol-specific CRFs when the information corresponding to that visit is available. 
Subjects will not be identified by name in the study database or on any study documents to be 
collected by the Sponsor (or designee) but will be identified by subject number and initials. 
If a correction is required for a CRF, the time and date will be recorded by the person updating 
CRF data to create an audit trail. The Investigator is responsible for all information collected on 
subjects enrolled in this study. All data collected during the study must be reviewed and verified 
for completeness and accuracy by the Investigator. A copy of the CRF will remain at the 
Investigator’s site at the completion of the study. 
The data will be entered into a validated database.  A Data Management group will be responsible 
for data processing, in accordance with procedural documentation. Database lock will occur once 
quality assurance procedures have been completed. 
10.3.6 
Case Report Form 
An electronic data capture (EDC) system will be used in the study.    
 
10.3.7 
Publication 
The preparation and submittal for publication of manuscripts containing the study results shall be 
in accordance with a process determined by mutual written agreement among the study Sponsor 
and participating institutions. The publication or presentation of any study results shall comply 
with all applicable privacy laws.  

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Appendix 1 Guidance and Lifestyle Recommendations for Adolescents with NAFLD 
 
I. 
GUIDANCE (NICE NG49 AND CG189) 
 
Per National Institute for Health and Care Excellence (NICE) Quality standard [QS152],  adopting 
a healthy lifestyle can help to reduce the rate of progression of non-alcoholic fatty liver disease 
(NAFLD). Providing lifestyle advice to people with NAFLD can encourage them to consider 
changes they can make that might help them avoid more serious liver disease. 
 
NICE guideline (NG49) for NAFLD assessment and management states that people with 
NAFLD should: 
x 
Be advised that there is some evidence that exercise reduces liver fat content 
x 
Be advised that, if they drink alcohol, it is important to stay within the national 
recommended limits for alcohol consumption.  
x 
Not be offered omega-3 fatty acids because there is not enough evidence to recommend 
their use for people with NAFLD.  
x 
Be offered advice on physical activity and diet in line with NICE's guidelines 
on obesity and preventing excess weight gain regardless of their BMI. 
 
General lifestyle guidance per NICE Clinical guideline [CG189]  
x Behavior change strategies (stimulus control, self-monitoring, goal setting, rewards for 
reaching goals, problem solving) should be part of general lifestyle changes  
x Increase people's physical activity levels or decrease inactivity 
x Improve eating behavior (but children should not go on exclusion diets)  
x Improve the quality of the person's diet 
x Have realistic targets for outcomes other than weight loss, such as increased physical 
activity and healthier eating 
 
Physical activity guidance per NICE Clinical guideline [CG189]  
x 
Encourage children and young people to increase their level of physical activity, even if 
they do not lose weight as a result, because of the other health benefits exercise can bring 
(for example, reduced risk of type 2 diabetes and cardiovascular disease). Encourage 
children to do at least 60 minutes of moderate or greater intensity physical activity each 
day. The activity can be in 1 session or several sessions lasting 10 minutes or more.  
x 
Be aware that children and young people who are already overweight may need to do 
more than 60 minutes' activity.  
x 
Encourage children and young people to reduce inactive behaviors, such as sitting and 
watching television, using a computer or playing video games.  
x 
Give children and young people the opportunity and support to do more exercise in their 
daily lives (for example, walking, cycling, using the stairs and active play). Make the 
choice of activity with the child/adolescent, and ensure it is appropriate to their ability 
and confidence.  
x 
Give children and young people the opportunity and support to do more regular, 
structured physical activity (for example football, swimming, walking, or dancing, etc.). 

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Make the choice of activity with the child/adolescent, and ensure it is appropriate to their 
ability and confidence.  
Dietary guidance per NICE Clinical guideline [CG189]  
x 
Tailor dietary changes to food preferences and allow for a flexible and individual 
approach to reducing calorie intake.  
x 
Do not use unduly restrictive and nutritionally unbalanced diets, because they are 
ineffective in the long term and can be harmful.  
x 
Encourage people to improve their diet even if they do not lose weight, because there can 
be other health benefits.  
x 
Any dietary changes should be age appropriate and consistent with healthy eating advice.  
 
 
II. 
LIFESTYLE RECOMMENDATIONS / ADVICE  IN THIS STUDY 
 
In this study which includes young people aged 12 to 17 years with fatty liver, lifestyle 
recommendations primarily centers on advice for making healthy food choices and encourages 
regular physical activity based on the circumstances of the individual. This advice is based on the 
principles of the NICE guidelines NG49 and CG189 outlined above. The parents/caregivers of 
study participants will be included in the consultation and advice for healthy lifestyle given to the 
family.  
 
The dietary advice will be consistent with healthy eating and are as follows:  
 
Limit/reduce*:  
x 
Sugar sweetened beverages (coca cola, lemonade, sports or energy drinks) plus excessive 
fruit juice intake. 
x 
Added sugar – high sugar cereals, yoghurts, and other milk-based drinks.  
x 
High-sugar, high-fat snack intake (crisps, doughnuts, chocolate biscuits) 
x 
Portion sizes of refined carbohydrates (white bread, white rice, cracker etc.) 
x 
Fast-food 
*Per the study protocol requirements, study participants while in the study are prohibited from 
consuming protein shakes, bars, gels, etc., or any other amino acid products, or any ketogenic 
products, or any other dietary supplements as noted in the study eligibility criteria and 
prohibited substances 
 
Encourage:  
x 
More vegetables 
x 
High-fiber versions of foods 
x 
A switch from fruit juice to whole fruit.  
x 
Healthy snacks: nuts and seeds, plain yoghurts, vegetables and dips.  
 
Develop important skills with cooperation and support from the family members  
x 
Reading nutrition labels 
x 
Meal planning and purchasing 
x 
Basic cooking skills, as age appropriate 
 

Protocol AXA1957-002 
v.3.0 
13-Dec-2019 
Page 77 of 77 
 
Axcella Health Inc.  
 
Confidential 
 
Potential actions that the dietician or other qualified staff may take based on the review of subject’s 
weekly compliance diaries may include: 
x If subjects are following lifestyle guidance, then they should be encouraged to continue 
following them. 
x If subjects are not following lifestyle guidance, then these recommendations and advice 
should be repeated and reinforced.