Dietary Study of a Complex Oligosaccharide With and Without a Probiotic Following Antibiotic Treatment in Healthy Volunteers
Conditions: Healthy Adults
Sponsor: Prolacta Bioscience

Official Title: Dietary Study of Human Milk Oligosaccharides with 
Bifidobacterium infantis in Antibiotic-treated Healthy Adult Volunteers 
Unique Protocol ID: 21-CT-003 
NCT ID: NCT05141903 
Document Date: 22 April 2022 

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TITLE PAGE 
CLINICAL STUDY PROTOCOL 
PROTOCOL TITLE: 
Dietary Study of Human Milk 
Oligosaccharides with Bifidobacterium infantis 
in Antibiotic-treated Healthy Adult 
Volunteers 
PROTOCOL NUMBER: 
21-CT-003 – Revision 5 
SPONSOR: 
Prolacta Bioscience 
1800 Highland Ave. 
Duarte, CA 91010 
SPONSOR’S MEDICAL 
MONITOR: 
David J Rechtman, M.D. 
VP, Medical Affairs  
SPONSOR PROJECT 
MANAGER: 
Gregory McKenzie, Ph.D. 
VP, Product Innovation 
Confidentiality Statement 
This protocol and its contents are the property of and confidential to Prolacta Bioscience, Inc.  This 
information is provided for the exclusive use of the investigators participating in this study.  Any and all 
confidential information contained herein may not be disclosed to any other person or party without the 
prior written consent of Prolacta Bioscience. 

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SIGNATURE PAGE 
Author Signature / Date: 
David J Rechtman, M.D. 
VP, Medical Affairs  
Date 
This study protocol has been reviewed and approved by the undersigned persons.  It is confirmed 
that the information and guidance given in this protocol complies with scientific principles, the 
guidelines of Good Clinical Practices, the Declaration of Helsinki in the latest relevant version 
and the applicable legal and regulatory requirements.  
Martin Lee, Ph.D. 
VP, Clinical Research & Development 
Date 
Gregory McKenzie, Ph.D 
VP, Product Innovation 
Date 

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INVESTIGATOR PROTOCOL AGREEMENT 
The signature below constitutes that I agree to the following: 
•
I have reviewed the protocol and the attachment(s).
•
This study will be conducted according to all stipulations of the protocol, including all
statements regarding confidentiality, and according to local legal and regulatory requirements
and applicable United States federal regulations, International Conference on Harmonization
(ICH) guidelines, Health Insurance Portability and Accountability Act (HIPAA) guidelines.
•
I agree to periodic site monitoring of source documents by Prolacta Bioscience or designee
and by appropriate regulatory authorities.
•
I agree to supply Prolacta Bioscience with any information regarding ownership interest and
financial ties with the Sponsor for the purpose of complying with regulatory requirements.
Investigator Name (Print) 
Investigator Signature 
Date 

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TABLE OF CONTENTS 
TITLE PAGE .............................................................................................................................. 1 
SIGNATURE PAGE ................................................................................................................... 2 
INVESTIGATOR PROTOCOL AGREEMENT ........................................................................ 3 
TABLE OF CONTENTS ............................................................................................................ 4 
BACKGROUND AND HYPOTHESIS...................................................................................... 5 
BACKGROUND ......................................................................................................................... 5 
HYPOTHESIS ............................................................................................................................ 6 
METHODS.................................................................................................................................. 7 
SAMPLE SIZE ............................................................................................................................ 9 
STUDY POPULATION ............................................................................................................. 9 
INCLUSION CRITERIA ............................................................................................................ 9 
EXCLUSION CRITERIA ......................................................................................................... 10 
STUDY PROCEDURE ............................................................................................................. 11 
STOOL SAMPLES ................................................................................................................... 12 
ANALYSIS OF STOOL SAMPLES ........................................................................................ 12 
BLOOD SAMPLES .................................................................................................................. 13 
URINE SAMPLES .................................................................................................................... 13 
VITAL SIGNS AND PHYSICAL EXAMS ............................................................................. 14 
CHEEK SWABS ....................................................................................................................... 14 
SUBJECT STOOL COMPLIANCE ......................................................................................... 14 
SUBJECT IP COMPLIANCE .................................................................................................. 14 
SAFETY STOPPING RULES .................................................................................................. 15 
STUDY ENDPOINTS .............................................................................................................. 16 
STATISTICAL EVALUATION............................................................................................... 17 
REFERENCES .......................................................................................................................... 18 
APPENDICES ........................................................................................................................... 19 
 
 
 

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Background and Hypothesis 
Dietary Study of Human Milk Oligosaccharides with Bifidobacterium infantis in Antibiotic-
treated Healthy Adult Volunteers 
Background 
Human milk oligosaccharides (HMO) have recently become the objects of scientific inquiry. 
These complex sugars are extremely heat stable and are therefore found intact in donor milk and 
human milk-based products following pasteurization as well as in untreated mother’s own milk 
(Barile, 2008) (D. Barile, 2009). (M Ninonuevo, 2006). Approximately 200 different HMO 
structures have been identified, although any particular mother will only produce a subset of 
these (Ayechu-Muruzabal, 2018). Studies have shown that HMO can alter the gut microbiome 
by favoring the growth of certain organisms as well as, perhaps, by inhibiting others (Smilowtiz, 
2014). It has also been demonstrated that HMO can act as “decoy” receptors for a variety of 
pathogens and toxins. (Smilowtiz, 2014). They have also been shown to directly interact with 
certain components of the adaptive immune system in vitro (Smilowtiz, 2014). 
It is therefore reasonable to expect that these molecules may be useful as therapeutic agents or 
medical foods. This is particularly the case in medical settings where the HMO themselves  or 
their metabolites may provide missing nutrients or other metabolic products for the dietary 
management of diseases where the microbiome plays a role, either in whole or in part. Examples 
include conditions as disparate as inflammatory bowel disease and stem cell transplantation. 
We hypothesize that Bifidobacterium longum subspecies infantis (B. infantis) might be a 
particularly beneficial organism to expand in the microbiome when managing such diseases in 
combination with HMO.  In infants, co-administration of B. infantis with human milk (via breast 
feeding) results in expansion of B. infantis, reduction in other potentially deleterious species, 
notably members of the Family Enterobacteriaceae, and acidification of baby’s stool through the 
production of certain short chain fatty acids (Frese, 2017).  These dietary effects are postulated to 
be due to metabolism of HMO by B. infantis, as infants receiving human milk in the absence of 
B. infantis don’t show these effects (Frese, 2017).  Importantly, B. infantis is not observed as a 
constituent of the human adult gut microbiota so it may therefore be necessary to administer both 
HMO and B. infantis to obtain the full beneficial impact of HMO in adults. 

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Prolacta Bioscience recently completed a study in healthy volunteers which demonstrated that a 
concentrate of HMO derived from human milk can drive B. infantis colonization in some healthy 
volunteers (20-CT-001, 2020). The purpose of this study, 21-CT-003, is three-fold. One goal is 
to determine if the rate of HMO-supported colonization with B. infantis is increased if the 
microbiome of the volunteers has been disrupted by administration of antibiotics.  The second 
goal is to determine whether microbiome recovery post-antibiotic treatment can be improved by 
the presence of B. infantis.  The third goal is to determine the mechanism of HMO-supported 
colonization; whether a selected subset of HMO (2’FL + LNnT) can support B. infantis 
colonization to the same extent as the full complement of HMO present in the HMO concentrate 
used previously.   
The HMO concentrate PBCLN-010 is a frozen liquid 15% concentration of HMO derived from 
the permeate obtained in concentrating donor human milk during the manufacturing of Prolacta’s 
human milk fortifiers. Previous versions of this product at 5% and 10% concentrations have been 
studied as a food supplement in healthy volunteers, either alone or in combination with B. 
infantis. A previous version has also been studied alone in C. difficile patients. No serious 
product-related adverse events have been reported in the course of these studies.  
The synthetic HMO 2’FL + LNnT product in this trial is a powder containing 2’-fucosyllactose 
(2’-FL) and lactoneotetraose (LNnT).  These HMO were also present in Prolacta’s previous 
HMO studies, where donor-derived HMO concentrates were administered to subjects with no 
adverse events recorded.  Here, they are present in a more purified mixture without the other 
HMO found in material used in the earlier trials.  This HMO product is commercially available 
as a medical food in the US. 
The B. infantis preparation being used in this trial is a dietary supplement commercially available 
in the United States and marketed for use in infants.  B. infantis is characterized as “generally 
regarded as safe” (GRAS) (Duar, 2020). 
Hypothesis 
We hypothesize that the rate of B. infantis colonization will increase following microbiome 
disruption, microbiome recovery will be enhanced, and that a similar effect may be seen with use 
of the specific synthetic HMO. 

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We hypothesize that ingestion of HMO with B. infantis after antibiotic treatment will result in a 
change in immune markers as was seen previously in study 16-CLN-003 (16-CLN-003, 2016), 
where HMO concentrate was consumed by healthy volunteers. We will, therefore, evaluate 
changes in circulating cytokine and growth factor levels following the ingestion of the IP 
compared to baseline levels and between dose groups. 
We believe that the changes in the microbiome, and possibly the changes in immune markers as 
a surrogate for immune activity, may be important in improving the clinical course of patients 
with certain diseases thought to be impacted by the microbiome.  
Methods 
We propose to conduct an unblinded five dosing group trial using 18 subjects per dosing group 
for a total of 90 healthy adult volunteers ages 18-75. The randomization scheme for this study is 
as follows.  The first twenty subjects will be randomized into Dosing Group 1 or 2 using a 
randomized permuted block scheme.  The next thirty four subjects will be randomized into 
Dosing Group 1, 2, or 3 using a similar separate randomized permuted block scheme employing 
a 4:4:9 ratio (group 1:group 2:group 3) in a block of 17.  The remaining thirty six subjects will be 
randomized into Dosing Groups 4 or 5 using a separate but similar randomized permuted block 
approach employing a 1:1 ratio (group 4:group 5). 
The IP and medications for this study include: antibiotics, HMO PBCLN-010, HMO 2’FL + 
LNnT, and B. infantis. 
Antibiotics will be given to all subjects in this study: vancomycin (250 mg/dose) and 
metronidazole (500 mg/dose).  
HMO PBCLN-010 is a frozen liquid, 15% concentration of HMO derived from the permeate 
obtained in concentrating donor human milk during the manufacturing of Prolacta’s human milk 
fortifiers.  
The HMO 2’FL + LNnT will be presented as individual lyophilized powder stick packs to be 
mixed with an appropriate diluent prior to ingestion.   
B. infantis ≥ 8X109 CFU will be presented as individual lyophilized powder sachets to be mixed 
with an appropriate diluent prior to ingestion.   

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The dosing regime is outlined as follows, refer to Table 1 additionally. 
Subjects randomized to Dosing Group 1 will consume antibiotics three times daily (TID) for 5 
days.  Subjects will be followed from the first dose of the antibiotics (day 1) until day 35. 
Subjects randomized to Dosing Group 2 will consume antibiotics three times daily (TID) for 5 
days, HMO PBCLN-010 twice daily for 28 days and B. infantis once daily for 14 days.  They 
will be followed from the first dose of the IP (day 1) until day 35. 
Subjects randomized to Dosing Group 3 will consume antibiotics three times daily (TID) for 5 
days and B. infantis once daily for 14 days.  They will be followed from the first dose of the IP 
(day 1) until day 35.  
Subjects randomized to Dosing Group 4 will consume antibiotics three times daily (TID) for 5 
days, HMO PBCLN-010 twice daily for 14 days, B. infantis once daily for 14 days, and HMO 
2’FL + LNnT twice daily for 14 days (to begin after HMO PBCLN-010 dosing has ended).  They 
will be followed from the first dose of the IP (day 1) until day 35. 
Subjects randomized to Dosing Group 5 will consume antibiotics three times daily (TID) for 5 
days, B. infantis once daily for 14 days, and HMO 2’FL + LNnT twice daily for 28 days.  They 
will be followed from the first dose of the IP (day 1) until day 35. 
 
 

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Table 1 Dosing Cohorts Regime 
Dosing 
Group 
vancomycin  
(250 mg/dose) and 
metronidazole  
(500 mg/dose) 
(1 tablet of each antibiotic 
three times per day)  
B. infantis 
(1 sachet  
once per day) 
Daily target=18g 
HMO PBCLN-010 
(9g twice per day) 
Daily target=22g 
HMO 2’FL + LNnT 
(2 sachets  
twice per day) 
1 
D1 – D5 
None 
None 
None 
2 
D1 – D5 
D1 – D14 
D1 – D28 
None 
3 
D1 – D5 
D1 – D14 
None 
None 
4 
D1 – D5 
D1 – D14 
D1 – D14  
D15 – D28 
5 
D1 – D5 
D1 – D14 
None 
D1 – D28 
Previous versions of the HMO concentrate in this study (PBCLN-010) differing only in HMO 
concentration, are food supplements that have been studied in human healthy volunteers in the 
past with no serious adverse events reported (16-CLN-003, 2016) (20-CT-001, 2020). The 
synthetic HMO 2’FL + LNnT is a commercially available medical food in powder form, and the 
B. infantis is a commercially available food supplement in powder form both of which are 
Generally Regarded As Safe (GRAS) (Duar, 2020) (Walsh, 2020). Therefore, this study will not 
be conducted in the manner of a dose escalation safety study. Dosing Groups 1 and 2 will be 
filled first and Dosing Groups 3, 4, and 5 will be filled once Dosing Groups 1 and 2 subjects 
have completed the study.   
Sample Size 
Five dosing groups of 18 subjects, each will be included in this study for a total sample size of 
90. The sample size was not determined statistically, but rather represents a typical number for 
an exploratory study in healthy volunteers. 
Study Population 
Each subject must meet all of the indicated inclusion criteria and none of the exclusion criteria 
noted below.  
Inclusion Criteria 
• Healthy adults between the ages of 18-75 years (subjects must be 18-75 at the time of 
consent) who can provide proof of vaccination against SARS-CoV-2. Proof may be a 

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physical or electronic record of vaccination or self-attestation (to include approximate 
vaccination date and manufacturer of vaccine) if a copy of the vaccination record is 
not available 
• Subjects must have a BMI of 18 - 30 at screening visit 
• Willingness to complete study specific questionnaires 
• Willingness to complete journal to record IP dosing times, Bristol stool scores, and IP 
flavor questionnaires 
• Willingness to complete all study procedures, clinic visits, and provide required 
biospecimen samples 
•  Willingness to collect and process stool samples at home and transport stool samples 
to clinic 
• Sexually active females of child-bearing potential must agree to use highly effective 
methods of contraception during heterosexual intercourse throughout the study period 
and for three days following discontinuation of IP, whichever comes later.  Examples 
of highly effective methods include the use of two forms of contraception with one 
being an effective barrier method (e.g., a condom and spermicide used together), or 
have a vasectomised partner. Abstinence is acceptable as a life-style choice. Female 
subjects who utilize hormonal contraceptives as one of their birth control methods 
must have used the same method for at least 3 months before study dosing 
• Provide informed consent  
Exclusion Criteria 
• Subjects with a BMI of 17 or less or 31 or greater are excluded 
• Women who are pregnant or breastfeeding, or intend to become pregnant during the 
course of this study 
• Subjects who intend to take a probiotic during the study 
• Subjects with self-reported diarrhea on day 1 prior to dosing, whereby diarrhea is 
defined as two or more episodes of watery and/or unformed stool within 24 hours 
• Alcohol or drug abuse during the last 12 months, including passing a screen for drugs 
of abuse at screening and day 1 of the study  
• Unstable medical condition, in the opinion of the investigator 

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• Subject with a history of allergy to vancomycin and/or metronidazole 
• Clinically significant abnormal laboratory test results at screening 
• Subjects who are unable or unwilling to provide stool samples on a regular basis as 
per study protocol 
• Participation in a clinical research trial within 30 days prior to screening 
• Unable to give informed consent 
• Any condition which may preclude subject’s ability to comply with and complete the 
study or may pose a risk to the health of the subject 
• Known carriers of C. difficile prior to study start, as determined by qPCR of stool 
• Known carriers of vancomycin-resistant enterococci (VRE) prior to study start, as 
determined by stool culture 
• Subjects with history of lactose intolerance 
Study Procedure 
Screening Visit may occur up to and including 90 days prior (≤ 90 days prior D1) to the subject’s 
first dose.  After informed consent is obtained and subject eligibility is assessed, a physical exam 
will be performed, vital signs, samples of blood, stool, and urine will be obtained from subjects 
at screening visit (≤ 90 days prior D1).  Prior to dosing on day 1, subject eligibility will be 
reassessed, vital signs, samples of blood, urine, and stool will be obtained from subjects.   
Samples of blood, urine and stool from all subjects will be taken at screening (≤ 90 days prior 
D1). Blood samples will be drawn on days 1, 3, 5, 9 (+1 day), 14 (+2 days), 28 (+2 days), and 35 
(+2 days).  Urine samples will be taken on days 1, 3, 5, and 35 (+2 days). Stool samples will also 
be required on days 1, 3, 4, 5, 7 (+1 day), 9 (+1 day), 11 (+2 days), 14 (+2 days), 17 (+2 days), 
21 (+2 days), 28 (+2 days) and 35 (+2 days).  
Some subjects, at the discretion of the sponsor, may be asked to return to the study site and 
provide a stool sample on or after Day 90.  These completed subjects may potentially no longer 
meet the Inclusion/Exclusion criteria nor conform to the dietary/medical restrictions in place for 
the first 35 study days. Refer to the Post Study Sample Schedule of Events for required events 
for these subjects. 

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Stool Samples 
Stool samples collected at screening (≤ 90 days prior to D1) will be analyzed by qPCR to 
determine if the subject is a carrier of C. difficile. Stool samples will also be analyzed via culture 
for vancomycin-resistant enterococci (VRE).  Subjects that are identified as C. difficile and/or 
vancomycin-resistant enterococci (VRE) carriers at the time of screening will be considered a 
screen fail. Screening (≤ 90 days prior to D1) stool samples collected for microbiological, 
metabolomic and metagenomic testing to answer questions of interest to sponsor will not be used 
to determine patient eligibility. Stool samples will be collected throughout the study for 
microbiological, metabolomic and metagenomic analyses (days 1, 3, 4, 5, 7 (+1 day), 9 (+1 day), 
11 (+2 days), 14 (+2 days), 17 (+2 days), 21 (+2 days), 28 (+2 days) and 35 (+2 days).   
Microbiological analysis will also be conducted on the post study sample (day 90 or later) for 
those subjects who have been identified by the sponsor to provide a post study sample (day 90 or 
later). 
 
At-home stool samples will be collected on days 4, 7 (+1 day), 11 (+2 days), 17 (+2 days), and 
21 (+2 days). The at-home stool samples will be collected by the subject into a commercially 
purchased container containing 95% ethanol for use as a preservative.   
 
On days 1, 3, 5, 9 (+1 day), 14 (+2 days), 28 (+2 days) and 35 (+2 days) subjects will deposit 
their stool in a provided collection kit and bring the entire sample to the clinic for processing by 
the site.  Alternatively, on these days the subjects may opt to provide the specimen during the 
course of visit to the study center. Collection and stool processing procedures are described in 
the accompanying Laboratory Manual. 
 
A post study sample will be collected on or after Day 90 for subjects as specified by the sponsor.  
These samples will be collected on site; collection and stool processing procedures are described 
in the accompanying Laboratory Manual.    
Analysis of Stool Samples 
Stool samples for microbiome analysis will be prepared for DNA extraction.  After DNA 
extraction, a sample will be analyzed using species- and strain-specific quantitative PCR analysis 
to evaluate B. infantis colonization and to monitor overall shifts in the microbiome using primers 

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that target the universal 16S rRNA gene shared by bacteria.  Selected samples may also be 
analyzed by next generation DNA sequencing to determine the taxonomic composition, alpha- 
and beta-diversity and change of each subject’s microbiome during the study.  Methods may 
include 16S and/or whole metagenomic shotgun sequencing and culture-specific methods as 
deemed appropriate by the Sponsor. In the event of a supposed sample mix-up, the sponsor may 
analyze subjects’ DNA isolated from a stool sample to confirm that all stool samples provided 
from a subject have the same DNA footprint.  
Aliquots of stool from Days 1, 3, 4, 5, 7, 9, 11, 14, 17, 21, 28, 35,will be provided to contract 
lab(s) with metabolomic capabilities to measure production of short chain fatty acids, levels of 
HMO, and additional microbial metabolites as deemed appropriate by the Sponsor.    
Blood Samples 
Blood samples collected at screening (≤ 90 days prior D1) will be used to determine subject 
eligibility and baseline results.  Blood samples will be collected and tested for the purpose of 
safety monitoring on days 1, 3, 5, 9 (+1 day), 14 (+2 days), 28 (+2 days) and 35 (+2 days).  
Specifically, the following tests will be performed: CBC with differential and platelets; alkaline 
phosphatase, ALT, AST, LDH, total and conjugated bilirubin, albumin, and total protein for liver 
function; electrolytes Na, K, Cl, HCO3, and glucose; total calcium, magnesium, and phosphate; 
creatinine and BUN for renal function. Blood will also be taken at screening to test for markers 
of immunological activity, including but not limited to, TGFβ.  Immunology samples taken at 
screening will not be used for subject eligibility. Additional blood samples will be drawn on days 
1, 3, 5, 9 (+1 day), 14 (+2 days), 28 (+2 days) and 35 (+2 days). These additional blood draws 
will be used to assess levels of immunological markers, levels of metabolites related to 
microbiome function in the serum, and levels of HMO. All blood testing for safety and 
immunological testing will be performed at a central clinical laboratory. 
Urine Samples 
Urine samples collected at screening (≤ 90 days prior to D1) and on day 1 will be used to screen 
for drugs of abuse.  Females of child-bearing potential will also provide urine for screening 
pregnancy tests at screening (≤ 90 days prior D1) and on day 1.  If child-bearing status is 
unknown, a urine pregnancy test should be performed at both visits.  Urine samples will be 
collected on days 1, 3, 5, and 35 (+2 days) for indoxyl sulfate tests. Urine creatinine tests will 

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also be conducted on days 1, 3, 5, and 35 (+2 days), the results will be used in conjunction with 
the indoxyl sulfate tests.  Urine samples will be aliquoted and frozen at -70 deg C or colder 
immediately after collection.  All urine samples for indoxyl sulfate testing will be sent to at a 
central clinical laboratory for testing. 
Vital Signs and Physical Exams 
Vitals signs, including temperature, blood pressure (BP), pulse, and respiration rate (RR), will be 
taken at screening (≤ 90 days prior to D1), day 1 and 35 (+2 days) .  Subjects should rest for at 
least 10 mins prior to taking vitals. Vitals should be taken prior to any blood draws and in a 
sitting or supine position.  Height, weight, and body mass index (BMI) will be taken only at the 
screening visit (≤ 90 days prior to D1). Physical exams will be performed at screening (≤ 90 days 
prior to D1) and at the day 35 visit. 
Cheek Swabs 
A cheek swab will be taken on day 1 of the study to determine secretor status of an individual by 
testing of a single region of DNA. Secretor status may impact the subject’s response to treatment 
which is the reason for this test.  
Subject Stool compliance 
Subjects will be considered evaluable if each subject provides 80% of stool samples through day 
35, including at least 1 stool sample from day 1, and at least 1 sample from days 3 through 5.  
Subjects who do not meet this criterion will be replaced.   
Subject IP compliance 
Subject compliance will be evaluated as follows: 
• Subjects will return all IP and medication (used and unused containers). 
• Subjects will record the date and times that the subject ingested IP and medication in a 
take home journal.  
• The study site will use a defined mechanism (daily phone call and/or text messaging and/ 
daily email) to remind subject regarding daily dose and to gain confirmation that dosing 
has been completed.  Any phone, text and/or email interactions will be documented as 
part of the study records. 
• In addition, the metabolomic measurement of HMO and the quantitative measurement of 
B. infantis will provide additional evidence of subject compliance (albeit after the fact). 

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Subject non-compliance will be defined as a B. infantis signal below the limit of 
detection (LOD) of the qPCR assay on days 3 – 14 during the dosing period. We are 
setting the LOD at 27 copies per nanogram DNA. The LOD was determined using the 
FDA validation requirements, which defines LOD as the lowest value that produces 
positive results amongst 12 replicates of the same sample using dilution series of 
genomic DNA isolated from B. infantis. The LOD was increased 35% to account for 
variability across operators, which is in compliance with FDA repeatability and 
reproducibility standards. If a subject’s sample yields a value lower than determined 
LOD, including no amplification, there is no B. infantis detected and the subject is 
deemed non-compliant. These criteria hold for every sample collected during the dosing 
period of B. infantis (days 3 – 14). 
• Subjects who miss a dose of B. infantis, HMO or both will make up the missed dosed by 
adding one additional B. infantis, HMO,  or both to their dosing regimen.  No more than 
2 consecutive missed doses or 3 total missed are allowed over the study.  Subjects who 
do not meet these criteria may be replaced. 
• Subjects who miss any doses of either antibiotic (metronidazole and/or vancomycin) in 
the first three days will be removed from the study.  No more than 2 doses may be missed 
after the ninth dose.  Subjects who do not meet these criteria may be replaced. 
Safety Stopping Rules 
• As the use of antibiotics in this protocol is intended to disrupt the intestinal microbiome 
of the subjects, it is anticipated that changes in bowel habits and/or other abdominal 
symptoms may ensue. A subject presenting with bloody diarrhea or severe abdominal 
pain with diarrhea shall be removed from the study and replaced. The study will be 
paused if 2 or more subjects are removed due to bloody diarrhea or severe abdominal 
pain with diarrhea. In collaboration with the study investigators, the Sponsor will 
determine if the antibiotic regimen will be changed to address this issue, or if the study 
will be terminated. 
• In the presence of diarrhea (whereby diarrhea is defined as two or more episodes of 
watery and/ or unformed stool within 24 hours) without blood, and with or without mild 
to moderate abdominal pain, antibiotic dosing will be discontinued, but the subject will 
remain on study. 

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Study endpoints 
A data collection spreadsheet will be provided in order to capture the relevant information that 
will be obtained by the clinical site as indicated below.  For primary endpoint and microbiome 
/metabolomic data, the Sponsor will be responsible for capturing data and incorporating into an 
appropriate database. 
a) Primary Endpoint 
• The primary endpoint will be changes in the level of B. infantis from baseline evaluated 
by quantitative PCR using strain specific primers.  Quantitation limits will be 
demonstrated by qualification assays demonstrating the lower limit of detection in order 
to establish minimum log-fold change in B. infantis, as it is expected that adult subjects 
will not harbor B. infantis in baseline samples. 
b) Secondary Endpoints 
• Changes in stool microbiota will be measured as well as dynamic changes in the gut 
community structure. These changes will be evaluated by next generation sequencing 
using proportions of key bacterial operational taxonomic units (OTUs), relative 
abundance of various taxa, diversity (alpha and beta) and stability of communities and 
functional metabolomic changes. Genera- and family-specific primers will also be used to 
perform qPCR to gauge changes in the microbial community structure.  
• Changes in viability of Proteobacteria and Enterococcus will be determined by plating on 
selective media.  These measurements will be predictive for success in suppressing 
pathogenic bacterial relatives in future trials. 
• Changes in the carriage load of antibiotic resistance genes will also be monitored using a 
set of qPCR primers and probes targeting antibiotic resistance genes. 
c) Blood parameters, including cytokine levels, will be evaluated at the screening visit and on 
study days 1, 3, 5, 9, 14, 28 and 35. Serum will also be assessed for metabolite levels, 
including but not limited to HMO, short chain fatty acids, and indole. 
d) Secretor status will be determined by analyzing DNA collected via a cheek swab  
e) Adverse events will be summarized by severity and relationship to study product. All adverse 
events will be reported on the study case report form designated for this purpose. Any serious 
and unexpected adverse event determined by the investigator to be definitely or highly likely 

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causally related with the consumption of IP should be reported immediately (but no later than 
within 24 hours) to the Sponsor’s Medical Monitor. 
Statistical evaluation 
Since this is an initial study of the use of antibiotics and HMO in combination with B. infantis, it 
is, by definition, hypothesis-generating. Therefore, all statistical analyses will be descriptive. The 
various indices reflecting the microbiome will be summarized with appropriate descriptive 
statistics at each day of collection and compared qualitatively across time and by dosing group.  
Other quantitative outcome data collected will be summarized by means/medians and standard 
deviations/inter-quartile ranges. Graphics such as box plots also will be presented. Safety data 
(tolerability and adverse events) will be presented in tables with proportions (per subject) by 
dose and overall. A more detailed Statistical Analysis Plan will be written and finalized before 
the completion of this study. 
 
 

Protocol Number: 21-CT-003  
 
Prolacta Bioscience 
Rev. 5                              
 
Page 18  
 
CONFIDENTIAL 
 
REFERENCES 
16-CLN-003. (2016). Phase I Safety Study of Human Milk Oligosaccharide Concentrate 
PBCLN-003 in Healthy Adult Volunteers. 
20-CT-001. (2020). 20-CT-001 Study Protocol “Dietary Study of Human Milk Oligosaccharides 
Concentrate PBCLN-005 with and without Bifidobacterium infantis in Healthy Adult 
Volunteers”. 
Ayechu-Muruzabal, V. (2018). Diversity of Human Milk Oligosaccharides and Effects on Early 
Life Immune Development. Frontiers in Pediatrics, https://doi.org/10.3389/fpred.2018.00239. 
Barile, D. (2008). Oligosaccharide prebiotics present in a breast milk based human milk fortifier.  
Hot Topics in Neonatology. Washington DC . 
D. Barile, B. G. (2009). Potential Novel Source for Human Oligosaccharides . American 
Academy of Pediatrics National Conference and Exhibit. Washington DC . 
Duar, R. a. (2020). Choosing a Probiotic for Infant Use: Why Bacterial Strain Matters. Neonatal 
Intensive Care, 24-26. 
Frese, S. (2017). Persistence of Supplemented Bifidobacterium longum subsp. infantis EVC001 
in Breastfed Infants. mSphere, e00501-17. 
Kelly, R. (1995). Sequence and expression of a candidate for the human Secretor blood group 
alpha (1,2) fucosyltransferase gene (FUT2). Homozygosity for an enzyme-inactivating nonsense 
mutation commonly correlates with the non-secretor phenotype. Journal of Biological Chemistry, 
4640-4649. 
M Ninonuevo, Y. P. (2006). A strategy to annotate the human milk glycome. Journal of 
Agriculture and Food Chemistry, 7471-7480. 
Ramirez, J. (2020). Antibiotics as Major Disruptors of Gut Microbiota. Fronteirs in Cellular and 
Infectious Microbiology, https://doi.org/10.3389/fcimb.2020.572912. 
Smilowtiz, J. L. (2014). Breast Milk Oligosaccharides: Structure-Function Relationships in the 
Neonate. Annual Reviews in Nutrition, 143-169. 
Walsh, C. (2020). From lab bench to formulated ingredient: Characterization, production and 
commercialization of human milk oligosaccharides. Journal of Functional Foods, 104052. 
 
 

Protocol Number: 21-CT-003  
 
Prolacta Bioscience 
Rev. 5                              
 
Page 19  
 
CONFIDENTIAL 
 
APPENDICES 
APPENDIX 1  
SCHEDULE OF EVENTS 
All activities for Dosing Groups 1 through 5 and the Post Study sample collection (for sponsor 
identified subjects only) are outlined in the Schedule of Events tables as follows.  

Protocol Number: 21-CT-003  
 
Prolacta Bioscience 
Rev. 5                              
 
Page 20  
 
CONFIDENTIAL 
 
DOSING GROUP 1 SCHEDULE OF EVENTS Days 1 – 14 
 
Screening
D0
Clinic visit
X
X
X
X
X
X
Final Visit 
Informed consent
X
Review IE Criteria
X
 X
Medical History
X
Physical Exam
X
Demographics (age, gender, ethnicity and 
race
X
Vital Signs (Temp, BP, pulse, RR)
X
X
Height, weight and BMI
X
Prior & Con Meds
X
X
AEs
X
X
X
X
X
Randomization
X
vancomycin 250 mg + metronidazole 500 mg 
(Q8 hours =/- 3 hours)
X
X
X
X
X
Assess IP and Stool compliance 
X
X
X
X
X
Patient Journal (Daily Dosing, Bristol Stool 
Score, and Flavor Questionnaire)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Patient Phone Calls 
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Urine Drug Screen Test
X
X
Urine Pregnancy Test (Females of child-
bearing potential)
X
X
Urine Creatinine Test
X
X
X
Frozen Urine aliquots (central lab - Indoxyl 
Sulfate)
X
X
X
Hematology &  Chemistry testing
X
X
X
X
X
X
Serum aliquots
X
X
X
X
X
X
C-diff and VRE Stool Screening Test
X
Stool aliquots (no preservatives)
X
X
X
X
X
X
Stool aliquots (with ethanol)
X
X
X
Cheek Swab for Secretor Status 
X
D5 
D12
D10
D9 
(+1day)
D6
D7 
(+1day)
D8 
Dosing Group 1 
Events
D1
D2
D3
D4
Dosing Days
(≤ 90 days 
prior D1
Washout Period
D11 
(+2days)
D13
D14 
(+2days)

Protocol Number: 21-CT-003  
 
Prolacta Bioscience 
Rev. 5                              
 
Page 21  
 
CONFIDENTIAL 
 
DOSING GROUP 1 SCHEDULE OF EVENTS Days 15 – 35  
 
Clinic visit
X
X
Final Visit 
 X
Informed consent
Review IE Criteria
Medical History
Physical Exam
X 
Demographics (age, gender, ethnicity and 
race
Vital Signs (Temp, BP, pulse, RR)
X
Height, weight and BMI
Prior & Con Meds
X
AEs
X
X
Randomization
vancomycin 250 mg + metronidazole 500 mg 
(Q8 hours =/- 3 hours)
Assess IP and Stool compliance 
X
Patient Journal (Daily Dosing, Bristol Stool 
Score, and Flavor Questionnaire)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Patient Phone Calls 
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Urine Drug Screen Test
Urine Pregnancy Test (Females of child-
bearing potential)
Urine Creatinine Test
X
Frozen Urine aliquots (central lab - Indoxyl 
Sulfate)
X
Hematology &  Chemistry testing
X
X
Serum aliquots
X
X
C-diff and VRE Stool Screening Test
Stool aliquots (no preservatives)
X
X
Stool aliquots (with ethanol)
X
X
Cheek Swab for Secretor Status 
D28 
(+2days)
D35 
(+2days)
D26
D24
Dosing Group 1 
Events
Washout Period
D27
D17 
(+2days)
D18
D19
D20
D21 
(+2days)
D22
D23
D15 
D16
D25

Protocol Number: 21-CT-003  
 
Prolacta Bioscience 
Rev. 5                              
 
Page 22  
 
CONFIDENTIAL 
 
DOSING GROUP 2 SCHEDULE OF EVENTS Days 1 – 14  
 
Screening
D0
Clinic visit
X
X
X
X
X
X
Final Visit 
Informed consent
X
Review IE Criteria
X
 X
Medical History
X
Physical Exam
X
Demographics (age, gender, ethnicity and 
race
X
Vital Signs (Temp, BP, pulse, RR)
X
X
Height, weight and BMI
X
Prior & Con Meds
X
X
AEs
X
X
X
X
X
Randomization
X
vancomycin 250 mg + metronidazole 500 mg  
(Q8 hours =/- 3 hours)
X
X
X
X
X
B. infantis (QD)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
HMO PBCLN-010 (BID)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Assess IP and Stool compliance 
X
X
X
X
X
X
Patient Journal (Daily Dosing, Bristol Stool 
Score, and Flavor Questionnaire)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Patient Phone Calls 
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Urine Drug Screen Test
X
X
Urine Pregnancy Test (Females of child-
bearing potential)
X
X
Urine Creatinine Test
X
X
X
Frozen Urine aliquots (central lab - Indoxyl 
Sulfate)
X
X
X
Hematology &  Chemistry testing
X
X
X
X
X
X
Serum aliquots
X
X
X
X
X
X
C-diff and VRE Stool Screening Test
X
Stool aliquots (no preservative)
X
X
X
X
X
X
Stool aliquots (with ethanol)
X
X
X
Cheek Swab for Secretor Status 
X
(≤ 90 days prior 
D1
D5 
D6
D7 
(+1day)
D8 
D9   
(+1day)
D10
D11   
(+2days)
D12
D13
D14       
(+2days)
Dosing Group 2
Events
D1
D2
D3
D4
Dosing Days

Protocol Number: 21-CT-003  
 
Prolacta Bioscience 
Rev. 5                              
 
Page 23  
 
CONFIDENTIAL 
 
DOSING GROUP 2 SCHEDULE OF EVENTS Days 15 – 35  
 
 
 
Washout
Clinic visit
X
X
Final Visit 
 X
Informed consent
Review IE Criteria
Medical History
Physical Exam
X 
Demographics (age, gender, ethnicity and 
race
Vital Signs (Temp, BP, pulse, RR)
X
Height, weight and BMI
Prior & Con Meds
X
AEs
X
X
Randomization
vancomycin 250 mg + metronidazole 500 mg  
(Q8 hours =/- 3 hours)
B. infantis (QD)
HMO PBCLN-010 (BID)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Assess IP and Stool compliance 
X
X
Patient Journal (Daily Dosing, Bristol Stool 
Score, and Flavor Questionnaire)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Patient Phone Calls 
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Urine Drug Screen Test
Urine Pregnancy Test (Females of child-
bearing potential)
Urine Creatinine Test
X
Frozen Urine aliquots (central lab - Indoxyl 
Sulfate)
X
Hematology &  Chemistry testing
X
X
Serum aliquots
X
X
C-diff and VRE Stool Screening Test
Stool aliquots (no preservative)
X
X
Stool aliquots (with ethanol)
X
X
Cheek Swab for Secretor Status 
Dosing Days
D19
D15 
D16
D17  
(+2days)
Dosing Group 2
Events
D18
D26
D27
D28 
(+2days)
D35 (+2days)
D20
D21 
(+2days)
D22
D23
D24
D25

Protocol Number: 21-CT-003  
 
Prolacta Bioscience 
Rev. 5                              
 
Page 24  
 
CONFIDENTIAL 
 
DOSING GROUP 3 SCHEDULE OF EVENTS Days 1-14 
 
Screening
D0
Clinic visit
X
X
X
X
X
X
Final Visit 
Informed consent
X
Review IE Criteria
X
 X
Medical History
X
Physical Exam
X
Demographics (age, gender, ethnicity and 
race
X
Vital Signs (Temp, BP, pulse, RR)
X
X
Height, weight and BMI
X
Prior & Con Meds
X
X
AEs
X
X
X
X
X
Randomization
X
vancomycin 250 mg + metronidazole 500 mg  
(Q8 hours =/- 3 hours)
X
X
X
X
X
B. infantis (QD)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Assess IP and Stool compliance 
X
X
X
X
X
X
Patient Journal (Daily Dosing, Bristol Stool 
Score, and Flavor Questionnaire)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Patient Phone Calls 
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Urine Drug Screen Test
X
X
Urine Pregnancy Test (Females of child-
bearing potential)
X
X
Urine Creatinine Test
X
X
X
Frozen Urine aliquots (central lab - Indoxyl 
Sulfate)
X
X
X
Hematology &  Chemistry testing
X
X
X
X
X
X
Serum aliquots
X
X
X
X
X
X
C-diff and VRE Stool Screening Test
X
Stool aliquots (no preservative)
X
X
X
X
X
X
Stool aliquots (with ethanol)
X
X
X
Cheek Swab for Secretor Status 
X
D5 
Dosing Group 3
Events
D1
D2
D3
D4
(≤ 90 days 
prior D1
Dosing Days
D7 
(+1day)
D8 
D9 
(+1day)
D10
D11 
(+2days)
D6
D12
D13
D14 
(+2days)

Protocol Number: 21-CT-003  
 
Prolacta Bioscience 
Rev. 5                              
 
Page 25  
 
CONFIDENTIAL 
 
DOSING GROUP 3 SCHEDULE OF EVENTS Days 15 - 35  
 
 
 
Clinic visit
X
X
Final Visit 
 X
Informed consent
Review IE Criteria
Medical History
Physical Exam
X 
Demographics (age, gender, ethnicity and 
race
Vital Signs (Temp, BP, pulse, RR)
X
Height, weight and BMI
Prior & Con Meds
X
AEs
X
X
Randomization
vancomycin 250 mg + metronidazole 500 mg  
(Q8 hours =/- 3 hours)
B. infantis (QD)
Assess IP and Stool compliance 
X
Patient Journal (Daily Dosing, Bristol Stool 
Score, and Flavor Questionnaire)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Patient Phone Calls 
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Urine Drug Screen Test
Urine Pregnancy Test (Females of child-
bearing potential)
Urine Creatinine Test
X
Frozen Urine aliquots (central lab - Indoxyl 
Sulfate)
X
Hematology &  Chemistry testing
X
X
Serum aliquots
X
X
C-diff and VRE Stool Screening Test
Stool aliquots (no preservative)
X
X
Stool aliquots (with ethanol)
X
X
Cheek Swab for Secretor Status 
D35 
(+2days)
D17 
(+2days)
D18
D15 
Dosing Group 3
Events
D16
Washout
D22
D23
D24
D20
D21 
(+2days)
D19
D25
D26
D27
D28 
(+2days)

Protocol Number: 21-CT-003  
 
Prolacta Bioscience 
Rev. 5                              
 
Page 26  
 
CONFIDENTIAL 
 
DOSING GROUP 4 SCHEDULE OF EVENTS Days 1 - 14  
 
 
 
Screening
D0
Clinic visit
X
X
X
X
X
X
Final Visit 
Informed consent
X
Review IE Criteria
X
 X
Medical History
X
Physical Exam
X
Demographics (age, gender, ethnicity and 
race
X
Vital Signs (Temp, BP, pulse, RR)
X
X
Height, weight and BMI
X
Prior & Con Meds
X
X
AEs
X
X
X
X
X
Randomization
X
vancomycin 250 mg + metronidazole 500 mg  
(Q8 hours =/- 3 hours)
X
X
X
X
X
B. infantis (QD)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
HMO PBCLN-010 (BID)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
HMO 2'FL + LNnT (Q12 hours)
Assess IP and Stool compliance 
X
X
X
X
X
X
Patient Journal (Daily Dosing, Bristol Stool 
Score, and Flavor Questionnaire)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Patient Phone Calls 
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Urine Drug Screen Test
X
X
Urine Pregnancy Test (Females of child-
bearing potential)
X
X
Urine Creatinine Test
X
X
X
Frozen Urine aliquots (central lab - Indoxyl 
Sulfate)
X
X
X
Hematology &  Chemistry testing
X
X
X
X
X
X
Serum aliquots
X
X
X
X
X
X
Stool aliquots (no preservative)
X
X
X
X
X
X
Stool aliquots (with ethanol)
X
X
X
Cheek Swab for Secretor Status 
X
D5 
D6
Dosing Group 4
Events
D1
D2
D3
D4
(≤ 90 days 
prior D1
D11 
(+2days)
D7 
(+1day)
Dosing Days
D8 
D9 
(+1day)
D10
D12
D13
D14 
(+2days)

Protocol Number: 21-CT-003  
 
Prolacta Bioscience 
Rev. 5                              
 
Page 27  
 
CONFIDENTIAL 
 
DOSING GROUP 4 SCHEDULE OF EVENTS Days 15 - 35  
 
 
 
Washout
Clinic visit
X
X
Final Visit 
 X
Informed consent
Review IE Criteria
Medical History
Physical Exam
X 
Demographics (age, gender, ethnicity and 
race
Vital Signs (Temp, BP, pulse, RR)
X
Height, weight and BMI
Prior & Con Meds
X
AEs
X
X
Randomization
vancomycin 250 mg + metronidazole 500 mg  
(Q8 hours =/- 3 hours)
B. infantis (QD)
HMO PBCLN-010 (BID)
HMO 2'FL + LNnT (Q12 hours)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Assess IP and Stool compliance 
X
X
Patient Journal (Daily Dosing, Bristol Stool 
Score, and Flavor Questionnaire)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Patient Phone Calls 
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Urine Drug Screen Test
Urine Pregnancy Test (Females of child-
bearing potential)
Urine Creatinine Test
X
Frozen Urine aliquots (central lab - Indoxyl 
Sulfate)
X
Hematology &  Chemistry testing
X
X
Serum aliquots
X
X
Stool aliquots (no preservative)
X
X
Stool aliquots (with ethanol)
X
X
Cheek Swab for Secretor Status 
Dosing Group 4
Events
D35 (+2days)
D20
D21 
(+2days)
D22
D23
D24
D25
D26
D27
Dosing Days
D28 
(+2days)
D16
D17 
(+2days)
D18
D19
D15 

Protocol Number: 21-CT-003  
 
Prolacta Bioscience 
Rev. 5                              
 
Page 28  
 
CONFIDENTIAL 
 
DOSING GROUP 5 SCHEDULE OF EVENTS Days 1 -14 
Screening
D0
Clinic visit
X
X
X
X
X
X
Final Visit 
Informed consent
X
Review IE Criteria
X
 X
Medical History
X
Physical Exam
X
Demographics (age, gender, ethnicity and 
race
X
Vital Signs (Temp, BP, pulse, RR)
X
X
Height, weight and BMI
X
Prior & Con Meds
X
X
AEs
X
X
X
X
X
Randomization
X
vancomycin 250 mg + metronidazole 500 mg  
(Q8 hours =/- 3 hours)
X
X
X
X
X
B. infantis (QD)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
HMO 2'FL + LNnT (Q12 hours)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Assess IP and Stool compliance 
X
X
X
X
X
X
Patient Journal (Daily Dosing, Bristol Stool 
Score, and Flavor Questionnaire)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Patient Phone Calls 
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Urine Drug Screen Test
X
X
Urine Pregnancy Test (Females of child-
bearing potential)
X
X
Urine Creatinine Test
X
X
X
Hematology &  Chemistry testing
X
X
X
X
X
X
Serum aliquots
X
X
X
X
X
X
C-diff and VRE Stool Screening Test
X
Stool aliquots (no preservative)
X
X
X
X
X
X
Stool aliquots (with ethanol)
X
X
X
Cheek Swab for Secretor Status 
X
D5 
D6
Dosing Group 5
Events
D1
D2
D3
D4
(≤ 90 days prior 
D1)
D11 
(+2days)
D7 
(+1day)
Dosing Days
D8 
D9 
(+1day)
D10
D12
D13
D14 
(+2days)

Protocol Number: 21-CT-003  
 
Prolacta Bioscience 
Rev. 5                              
 
Page 29  
 
CONFIDENTIAL 
 
DOSING GROUP 5 SCHEDULE OF EVENTS Days 15 – 35
 
 
 
Washout
Clinic visit
X
X
Final Visit 
 X
Informed consent
Review IE Criteria
Medical History
Physical Exam
X 
Demographics (age, gender, ethnicity and 
race
Vital Signs (Temp, BP, pulse, RR)
X
Height, weight and BMI
Prior & Con Meds
X
AEs
X
X
Randomization
vancomycin 250 mg + metronidazole 500 mg  
(Q8 hours =/- 3 hours)
B. infantis (QD)
HMO 2'FL + LNnT (Q12 hours)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Assess IP and Stool compliance 
X
X
Patient Journal (Daily Dosing, Bristol Stool 
Score, and Flavor Questionnaire)
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Patient Phone Calls 
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Urine Drug Screen Test
Urine Pregnancy Test (Females of child-
bearing potential)
Urine Creatinine Test
X
Hematology &  Chemistry testing
X
X
Serum aliquots
X
X
C-diff and VRE Stool Screening Test
Stool aliquots (no preservative)
X
X
Stool aliquots (with ethanol)
X
X
Cheek Swab for Secretor Status 
Dosing Group 5
Events
D35 (+2days)
D20
D21 
(+2days)
D22
D23
D24
D25
D26
D27
Dosing Days
D28 
(+2days)
D16
D17 
(+2days)
D18
D19
D15 

Protocol Number: 21-CT-003  
 
Prolacta Bioscience 
Rev. 5                              
 
Page 30  
 
CONFIDENTIAL 
 
POST STUDY SAMPLE SCHEDULE OF EVENTS (SPONSOR SELECTED SUBJECTS ONLY) 
Post Study Sample Events 
Post Study Sample - Sponsor Selected Subjects only 
D90 or later 
Clinic visit 
X 
Final Visit  
X 
Informed consent 
X 
Prior Meds - Antibiotics (only) taken since D35 
X 
Stool aliquots (no preservative) 
X