A Phase II Study of Metformin in Combination With Doxycycline in Patients With Localized Breast, and Uterine, and Cervical Cancer
Phase: PHASE2
Conditions: Breast Carcinoma, Endometrial Clear Cell Adenocarcinoma, Endometrial Serous Adenocarcinoma, Uterine Corpus Cancer, Uterine Corpus Carcinosarcoma
Sponsor: Sidney Kimmel Comprehensive Cancer Center at Thomas Jefferson University

Metformin and Doxycycline in Breast, Uterine and Cervical Cancer 
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THOMAS JEFFERSON UNIVERSITY 
Sidney Kimmel Cancer Center 
 
A Phase II Study of Metformin in Combination with Doxycycline in 
Patients with Localized Breast, Uterine and Cervical Cancer 
Principal 
Investigator: 
Jennifer M Johnson, MD PhD 
Department of Medical Oncology 
1015 Walnut Street, Suite 700 
Philadelphia, PA 19107 
215-955-8875 
 
Co-Investigator(s): 
Department of Medical Oncology 
Daniel Altman, MD 
1015 Walnut Street, Suite 700 
Philadelphia, PA 19107 
215-955-8875 
 
 
Breast Surgical Oncology 
 
 
Melissa A. Lazar, MD 
1100 Walnut Street 
7th Floor 
Philadelphia, PA 19107 
(215) 955-6999 
 
Alliric Willis, MD 
1100 Walnut Street 
Philadelphia, PA 19107 
(215) 955-5529 
 
Gynecology Surgical Oncology 
 
Norman Rosenblum, MD, PhD 
925 Chestnut Street 
Suite 320A 
Philadelphia, PA 19107  
Phone: (215) 955-6200  
 
Scott Richard, MD 
925 Chestnut Street 
Suite 320A 
Philadelphia, PA 19107 
Phone: (215) 955-6200 
 
Registered Dietician: 

Metformin and Doxycycline in Breast, Uterine and Cervical Cancer 
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Heather Bell-Temin 
925 Chestnut St. 
Suite 420A 
Phone: (215) 503-7653 
 
Biostatistician:  
Tingting Zhan, PhD 
Division of Biostatistics,  
Department of Pharmacology and Experimental Therapeutics 
1015 Chestnut Street, Suite 520 
Philadelphia, PA 19107 
 
Pathology:  
Madalina Tuluc, MD 
Department of Pathology 
132 South 10th Street, Second Floor 
 
Joanna Chan, MD 
Department of Pathology 
132 South 10th Street, Second Floor 
 
Correlative Science PI: 
Ubaldo Martinez Outschoorn, MD 
Department of Medical Oncology 
834 Chestnut Street, Suite 320 
Philadelphia, PA 19107 
215-955-5822 
 
Nicole Simone, MD 
Department of Radiation Oncology 
111 South 11th Street, Room G301N 
Philadelphia, PA 19107 
215-955-6702 
 
 
Funding Sponsor: 
 Sidney Kimmel Cancer Center 
IND/IDE Holder: 
NA 
IND/IDE Number: 
NA 
Study Product: 
Metformin 
Doxycycline 
Protocol IDs: 
JeffTrial # 8988 
PRC # 2016-025 
IRB Control # 16D.317 
 
Version Number: 
Version Date: 
1.1 
2.22.16 

Metformin and Doxycycline in Breast, Uterine and Cervical Cancer 
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CONFIDENTIAL 
This document is confidential and the property of THOMAS JEFFERSON UNIVERSITY. No part of it may be transmitted, 
reproduced, published, or used by other persons without prior written authorization from the study sponsor. 
 
 
1.2 
2.22.16 
2.0 
06.13.16 
2.0.1 
07.19.16 
2.1 
07.22.16 
2.2 
10.19.16 
3.0 
2.27.17 
4.0 
12.21.17 
4.1 
03.19.18 
4.2 
11.15.2018 
4.3 
23JAN2020 

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Table of Contents 
Signature Page ............................................................................................................................... 8 
Statement of Compliance ............................................................................................................... 8 
List of Abbreviations ....................................................................................................................... 9 
Study Summary ............................................................................................................................ 11 
1 
Introduction ............................................................................................................................. 14 
1.1 
Background Information .......................................................................... 15 
1.2 
Rationale ................................................................................................. 21 
1.3 
Correlative Studies .................................................................................. 22 
1.4 
Potential Risks and Benefits ................................................................... 23 
1.4.1 
Potential Benefits .................................................................................... 23 
1.4.2 
Potential Risks ......................................................................................... 23 
2 
Study Objectives .................................................................................................................... 24 
2.1 
Objectives ................................................................................................ 24 
2.1.1 
Primary .................................................................................................... 24 
2.1.2 
Secondary ............................................................................................... 24 
2.1.3 
Correlative ............................................................................................... 25 
2.2 
Endpoints/Outcome Measures................................................................ 25 
2.2.1 
Primary .................................................................................................... 25 
2.2.2 
Secondary ............................................................................................... 25 
3 
Study Design .......................................................................................................................... 25 
4 
Study Enrollment and Withdrawal .......................................................................................... 27 
4.1 
Subject Inclusion Criteria ........................................................................ 27 
4.2 
Subject Exclusion Criteria ....................................................................... 27 
4.3 
Gender/Minority/Pediatric Inclusion for Research .................................. 28 
4.4 
Recruitment and Screening .................................................................... 28 

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4.5 
Subject Withdrawal/Discontinuation Criteria ........................................... 29 
4.5.1 
Subject Replacement Strategy ............................................................... 29 
5 
Study Treatments ................................................................................................................... 29 
5.1 
Study Product .......................................................................................... 29 
5.2 
Study Product Description ...................................................................... 29 
5.2.1 
Dose Calculation ..................................................................................... 30 
5.2.2 
Packaging and Labeling Information ...................................................... 31 
5.2.3 
Clinical Supplies Disclosure .................................................................... 31 
5.2.4 
Receiving, Compliance, Storage and Return ......................................... 31 
5.2.5 
Dose Limiting Toxicity Criteria ................................................................ 32 
5.3 
Surgical Resection .................................................................................. 32 
5.4 
Concomitant Medications/Treatments .................................................... 33 
5.4.1 
Acceptable Concomitant Medications..................................................... 33 
5.4.2 
Prior and Concomitant Medication .......................................................... 33 
5.5 
Dietary Restrictions ................................................................................. 34 
6 
Study Procedure..................................................................................................................... 34 
6.1 
Screening Assessment ........................................................................... 38 
6.2 
Treatment Period (Week 1 Day 1 – day prior to Surgical Resection) .... 38 
6.3 
Surgical Resection .................................................................................. 39 
6.4 
End of Treatment Study Visit (Within 21 Days +7 of stopping protocol 
study medications) 39 
6.5 
Long term Follow-up ............................................................................... 39 
7 
Study Procedures and Evaluations ........................................................................................ 39 
7.1 
Administrative Procedures ...................................................................... 40 
7.1.1 
Informed Consent .................................................................................... 40 
7.1.2 
Inclusion/Exclusion Criteria ..................................................................... 40 
7.1.3 Medical History .............................................................................................................. 40 

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7.2 
Clinical Assessment ................................................................................ 41 
7.2.1 
Adverse Event (AE) Monitoring ............................................................... 41 
7.3 
Laboratory Safety Evaluations ................................................................ 41 
Table 3 
Laboratory Tests ...................................................................................... 41 
7.3.1 
Correlative Studies .................................................................................. 42 
8 
Safety Evaluations ................................................................................................................. 42 
8.1 
Specification of Safety Parameters ......................................................... 42 
8.1.1 
Unanticipated Problems .......................................................................... 42 
8.1.2 
Adverse Events ....................................................................................... 42 
8.2 
Safety Assessment and Follow-Up ......................................................... 43 
8.3 
Recording Adverse Events ..................................................................... 43 
8.3.1 
Relationship to Study Intervention .......................................................... 43 
8.3.2 
Expectedness .......................................................................................... 43 
8.3.3 
Severity of Event ..................................................................................... 43 
Table 4 
Evaluating Adverse Events ..................................................................... 45 
8.3.4 
Intervention .............................................................................................. 46 
8.4 
Safety Reporting...................................................................................... 46 
8.4.1 
Reporting to IRB ...................................................................................... 46 
8.4.2 
Reporting to SKCC DSMC ...................................................................... 46 
8.4.3 
Reporting of Pregnancy .......................................................................... 47 
8.5 
Halting Rules ........................................................................................... 47 
9 
Study Oversight ...................................................................................................................... 48 
10 
Statistical Analysis Plan .......................................................................... 48 
10.1 
General considerations: .......................................................................... 48 
10.2 
Analysis for primary outcomes. ............................................................... 48 
10.3 
Analysis for secondary outcomes. .......................................................... 48 

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10.4 
Sample size justification .......................................................................... 48 
10.5 
Interim analysis and early stopping. ....................................................... 48 
10.6 
Stopping rules for safety ......................................................................... 48 
11 
Data Handling and Record Keeping ....................................................... 49 
11.1 
Confidentiality .......................................................................................... 49 
11.2 
Source Documents .................................................................................. 49 
11.3 
Case Report Forms ................................................................................. 49 
11.4 
Study Records Retention ........................................................................ 50 
12 
Clinical Site Monitoring and Auditing ...................................................... 50 
13 
Ethical Considerations ............................................................................ 50 
13.1 
Good Clinical Practice ............................................................................. 51 
13.2 
Ethical Considerations ............................................................................ 51 
13.3 
Patient Information and Informed Consent ............................................. 51 
13.4 
Protection of Privacy ............................................................................... 52 
13.5 
Protocol Compliance ............................................................................... 52 
13.6 
Drug Accountability ................................................................................. 52 
13.7 
Terminating or Modifying the Study ........................................................ 52 
13.8 
Record Retention .................................................................................... 53 
14 
Study Finances ........................................................................................ 53 
14.1 
Funding Source ....................................................................................... 53 
14.2 
Conflict of Interest ................................................................................... 53 
14.3 
Compliance with Trial Registration and Results Posting Requirements 53 
15 
Publication Plan ....................................................................................... 53 
Literature References ................................................................................................................... 53 
 

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Signature Page 
The signature below constitutes the approval of this protocol and the attachments, and 
provides the necessary assurances that this trial 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 US federal 
regulations and ICH guidelines. 
Principal Investigator: 
Signed: 
 
Date:  
Name: 
Jennifer M Johnson, MD PhD 
Title:  
Principal Investigator 
Statement of Compliance 
This study will be conducted in accordance with the International Conference on Harmonisation 
guidelines for Good Clinical Practice (ICH E6), the Code of Federal Regulations on the 
Protection of Human Subjects (45 CFR Part 46), and Thomas Jefferson University research 
policies 
 
 
 

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List of Abbreviations 
AJCC 
American Joint Committee on Cancer 
AE 
Adverse Event/Adverse Experience 
AMPK 
AMP-activated Protein Kinase 
ATP 
Adenosine Triphosphate 
CAF 
Cancer Associated Fibroblast 
CAV1 
Caveolin-1 
CFR 
Code of Federal Regulations 
CIOMS 
Council for International Organizations of Medical Sciences 
CONSORT 
Consolidated Standards of Reporting Trials 
CRF 
Case Report Form 
CRO 
Contract Research Organization 
CSC 
Cancer Stem Cell 
CTCAE 
Common Terminology Criteria for Adverse Events 
CTO 
Clinical Trials Office 
DLT 
Dose Limiting Toxicity 
DSMC 
Data and Safety Monitoring Committee 
DSMP 
Data and Safety Monitoring Plan 
ECOG 
Eastern Cooperative Oncology Group  
ER 
Estrogen Receptor 
ESR 
Erythrocyte Sedimentation Rate 
FDA 
Food and Drug Administration 
FWA 
Federalwide Assurance 
GCP 
Good Clinical Practice 
HER2 
Human Epidermal Growth Factor Receptor 2 
HIPAA 
Health Insurance Portability and Accountability Act 
HNSCC 
Head and Neck Squamous Cell Carcinoma 
IB 
Investigator’s Brochure 
ICF 
Informed Consent Form 
ICH 
International Conference on Harmonisation 
IDE 
Investigational Device Exemption 
IHC 
Immunohistochemistry 
IND 
Investigational New Drug Application 
IGF-1 
Insulin-like Growth Factor 1 
IGF-BP3 
Insulin-like Growth Factor Binding Protein 3 

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IGFR 
Insulin Growth Factor Receptor 
IRB 
Institutional Review Board 
LKB1 
Liver Kinase B1 
MCT1 
Monocarboxylate Transporter 1 
MCT4 
Monocarboxylate Transporter 4 
MedDRA 
Medical Dictionary for Regulatory Activities 
MOP 
Manual of Procedures 
MSI 
Mass Spectroscopy Imaging 
mTORC1 
Mammalian Target of Rapamycin Complex 1 
N 
Number (typically refers to subjects) 
NCI 
National Cancer Institute 
OXPHOS 
Oxidative Phosphorylation 
PHI 
Protected Health Information 
PI 
Principal Investigator 
PR 
Progesterone Receptor 
PRC 
Protocol Review Committee 
QA 
Quality Assurance 
QC 
Quality Control 
ROS 
Reactive Oxygen Species 
SAE 
Serious Adverse Event/Serious Adverse Experience 
SKCC 
Sidney Kimmel Cancer Center 
SOP 
Standard Operating Procedure 
TOMM20 
Transporter of Outer Mitochondrial Membrane 20 
TSC2 
Tuberous Sclerosis Complex Tumor Suppressor Gene 2 
UP 
Unanticipated Problem 
 
 
 

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Study Summary 
Title:  
A Phase II Study of Metformin in Combination with Doxycycline in Patients with 
Localized Breast, Uterine and Cervical Cancers 
Lead Site: 
Thomas Jefferson University 
Sponsor: 
Investigator-Initiated Trial 
Phase: 
Phase II 
Objectives: 
Primary: 
• 
To determine if treatment with a combination of metformin and doxycycline can 
increase the percentage of cells that express Caveolin-1 in the cancer 
associated fibroblasts of patients with breast, uterine and cervical cancers. 
 
Secondary:  
• 
To determine the effect of metformin and doxycycline treatment on the 
percentage of cells that express MCT4 in cancer associated fibroblasts and 
MCT1 and TOMM20 in the cancer cells of breast, uterine and cervical cancer 
patients. 
• 
To assess safety and tolerability of metformin and doxycycline treatment in 
subjects with breast, uterine and cervical cancer. 
• 
To determine the relationship of the percentage of stromal cells expressing 
CAV1 or MCT4 and tumor cells that express MCT1 and TOMM20 at baseline 
and after treatment with metformin and doxycycline with the percentage of cells 
expressing ER and PR for breast, uterine and cervical samples and HER2 in 
breast cancer samples. 
 
Correlatives: 
• 
To assess the effect of combined metformin and doxycycline therapy on the 
metabolic profile of cancer cells and stroma using mass spectroscopy imaging 
(MSI) on paired samples, comparing metabolite profiles in the pre-metformin and 
post-metformin tumor samples.  
• 
To assess, when possible, the impact of a patient’s nutritional status, estimated 
using 3 day dietary recall versus caloric needs as calculated by the Harris-
Benedict equation on the baseline and net change in CAV1. 
• 
To assess the effect of combined metformin and doxycycline therapy on 
oncomiR miR-21 after intervention. 
• 
To assess the effect of combined metformin and doxycycline therapy on 
adipokines and the IGF-1/insulin signaling pathways through assessment of 
serum triglycerides, IGF-1, IGF-BP3, erythrocyte sedimentation rate (ESR), 
adiponectin, leptin, IGF-1R, exosome evaluation, metabolomics profile, and 
microRNA expression profiles. 
 
Target 
Population: 
• 
Patients aged 18 years and above 
 
• 
Known or suspected breast, uterine (endometrial cancer with histologies 
including endometrioid, serous, clear cell and carcinosarcoma), or cervical 
cancer. 

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• 
Have surgical intent for resection as a part of their planned therapy 
 
• 
Performance status ECOG 0-1 
 
• 
Normal organ function including creatinine <1.5 
 
Required 
Enrollment 
23 patients per cohort (breast and uterine/cervical) for a total of 46 patients 
Rationale: 
Metformin, a widely used anti-diabetic drug, which functions as a mitochondrial inhibitor, 
can also be used to selectively target cancer stem cells. Metformin functionally inhibits 
OXPHOS by targeting complex I of the electron transport chain and can even induce lactic 
acidosis, as a lethal side effect. As a result, the use of antibiotics, such as doxycycline, 
may provide a safer and far more effective alternative to anti-cancer therapy with 
metformin. Thus, future clinical trials for testing the efficacy of mitochondrial-targeted 
antibiotics in multiple cancer types are now clearly clinically warranted. 
Doxycycline is a broad-spectrum antibiotic that is commonly used for the treatment of 
many bacterial infections, and functions as an inhibitor of protein synthesis in bacteria. 
Doxycycline also encourages the growth of normal stem cells, has anti-inflammatory 
properties, and even increases cell lifespan, in certain experimental contexts. Thus, the 
toxic side effects of anti-cancer therapy would be minimized. Doxycycline has also been 
used in human tumor xenografts and other animal models to significantly reduce tumor 
burden and even metastatic cancer cell growth. For example, in pancreatic tumor 
xenografts (with PANC-1 cells), doxycycline treatment reduced tumor growth by ~80%. In 
a xenograft model of breast cancer bone metastasis (with MDA-MB-231 cells), 
doxycycline treatment reduced bone and bone-associated soft-tissue tumor mass by 
>60% and ~80%, respectively. 
Overall, the combination of metformin and doxycycline will co-target mitochondrial 
pathways and possible be synergistic to impair mitochondrial function that could lead to 
further cell quiescence. 
Study 
Design: 
Eligibility Screening
Cohort 
Trea
ment
Week 
-1 
1 
2 
3 45 
Day 
-
1 
1 
2 
3 
4 
5 
6 
7 
8* 
9 
10 
11 
12 
13 
14 
 
1 
N=23 
Doxycyclinee 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Surgical 
Resection 
Metformin 
 
X
a 
X
a 
X
a 
X
b 
X
b 
X
b 
Xc Xc 
Xc Xc 
Xc 
Xc 
X
c 
Xc 
2 
N= 
23 
Doxycyclinee 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Metformin 
 
X
a 
X
a 
X
a 
X
b 
X
b 
X
b 
Xc Xc 
Xc Xc 
Xc 
Xc 
X
c 
Xc 
 
Tissued 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
 
 

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* If surgery is scheduled past Day 8, patients will stay on metformin and doxycycline until the day prior to surgery. 
a. Metformin will be given initially with a starting dose of 500mg once a day for Days 1-3. 
b. Metformin will be increased to 500 mg orally twice a day for Days 4-6 
c. If tolerated, beginning Day 7 metformin will be increased to 1000 mg twice a day. Subjects will 
maintain the maximum tolerated dose (up to 1000 mg twice daily) until the day prior to their 
scheduled definitive surgery. 
d. When possible, baseline biopsy tissue is to be obtained prior to starting study medications.  Two 
serum separator tubes of serum will be taken at the same time as the biopsy specimen (if possible), 
otherwise done at time of consent.  If a pre-treatment sample has already been acquired and flash 
froze and if there is excess tissue available at resection, the second  specimen will also have a 
piece flash frozen for metabolomic testing. 
e. Doxycycline will be taken once every 12 hours, with the last dose being taken at least 12 hours 
prior to scheduled time of definitive surgery. 
 
Metformin and doxycycline are the therapeutic agents.  For metformin, the initial starting 
dose will be 500 mg orally daily for 3 days which will then be increased to 500 mg orally 
twice daily, and if tolerated, further increased to 1000 mg twice daily after day 6.  
Subjects will maintain the maximum tolerated dose (up to 1000 mg twice daily) until the 
day prior to their scheduled definitive surgery. 
For doxycycline the patients will take 100 mg by mouth every twelve hours until the day 
prior to their surgery. 
 
Criteria for 
Evaluation: 
Primary: 
• 
Assess the impact of metformin and doxycycline on the percentage of cancer 
associated fibroblasts that stain with 1+ intensity or greater for CAV1 by 
immunohistochemistry (IHC) pre and post metformin and doxycycline exposure 
as determined by two blinded pathologists.  All patients from whom samples are 
obtained both pre- and post-treatment will be included in the primary analyses. 
 
Secondary:  
• 
Assess the impact of metformin and doxycycline on the percentage of cancer-
associated fibroblasts that express MCT4 and the percentage of cancer cells 
that express MCT1 and TOMM20.  All patients from whom samples are obtained 
both pre- and post-treatment will be included in the secondary analyses.  
• 
Assess safety and tolerability of metformin and doxycycline treatment in subjects 
with cancer. Toxicity will be evaluated using the most recent version (version 4) 
of the NCI toxicity criteria, i.e. the NCI Common Terminology Criteria for Adverse 
Events (CTCAE) version 4.03.  
• 
The staining patterns of CAV1, MCT4, MCT1, and TOMM20 will be compared to 
the ER, PR, and Her2 expression levels whenever these markers have been 
performed in the course of clinical care. All patients from whom samples are 
obtained both pre- and post-treatment will be included in the secondary analyses 
 
Correlative: 
• 
Mass spectroscopy imaging (MSI) will be performed on paired samples, 
comparing metabolite profiles in the pre-treatment and post-treatment tumor 
sample. MSI allows assessment of metabolite levels in spatially defined tumor 
regions and hence will allow the evaluation of metabolite levels in carcinoma and 
stromal cell compartments.  Only patients for whom flash frozen samples can be 

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obtained both prior to initiation of treatment and in the OR at the time of 
resection will be considered for this analysis. 
• 
Patients who are able to complete, when possible, a 3 day recall dietary diary 
with the aid of a nutritionist will also have their caloric needs estimated with a 
Harris-Benedict Equation. 
• 
Patients from whom serum samples are available will be assessed for oncomiR-
21, IGF1, IGF-BP3, ESR, adiponectin, leptin, IGF-1R, and exosome and 
metabolomics profiles in exploratory analyses. 
 
Statistical 
Analysis: 
 
The primary objective of the study is to assess the impact of metformin and doxycycline 
on the percent of stromal cell that have CAV1 expression by immunohistochemistry (IHC) 
in carcinoma cells.  All patients from whom samples are obtained both pre- and post-
treatment will be included in the primary analyses.  Within-patient change in IHC scores 
will be analyzed using the Wilcoxon signed-rank test.  
 
The sample in each cohort is based on having 80% power to detect an average increase 
in CAV1 staining of 20% using a one-sided Wilcoxon signed-rank test with alpha=0.05.  
Based on pilot data in other cancers, we assume the standard deviation of change scores 
to be 32%.  A sample size of 19 per cohort is required under these assumptions.  Allowing 
for approximately 15% of patients to have missing pre- and or post-treatment data, we will 
recruit 23 women per cohort.   
 
Incidence of Dose Limiting Toxicities (DLTs) will be monitored continuously with potential 
stopping after 10 patients have been enrolled based on the Bayesian method of Thall and 
Simon.  We are comparing our experimental treatment to a standard of no treatment and 
assume no DLTs under standard of care.  Both agents are extremely safe and DLTs 
should be exceedingly rare.  In 900 patients treated with metformin alone, the 
discontinuation rate was 0.6%.  In 31 patients treated with IV doxycycline, 4 SAEs were 
observed, but none were related to the study drug.  Thus, it is reasonable to assume a 
prior distribution for the DLT rate in the combination of Beta (0.04,1.96). That is, we 
assume a 2% event rate for the combination with information equivalent to data from 2 
patients.  We will stop the study for safety if the posterior probability that the rate of DLTs 
in the combination treatment is 5% or greater is greater than 90%. 
  
Study 
Duration: 
48 months 
Subject 
Participation 
Duration: 
From the time that patients enroll in the trial until their definitive surgery is between 1-5 
weeks.  The patients’ records will then be reviewed every 3 months for the next 12 months. 
Estimated 
Time to 
Complete 
Enrollment: 
36 months 
 
1 Introduction 

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This document is a protocol for a human research study. This study will be conducted according 
to US and international standards of Good Clinical Practice (FDA Title 21 part 312 and 
International Conference on Harmonization guidelines), applicable government regulations and 
Institutional research policies and procedures.  
1.1 Background Information 
Current treatment Options for Breast, Uterine and Cervical Cancers. 
Multiple treatment options exist for “early stage” or “localized” cancers of the breast, uterus, and 
cervix.  Briefly, for breast cancer patients, those patients who are considered to have 
locoregional disease (AJCC stages I, II, IIB, or T3N1M0) are first offered either lumpectomy or 
mastectomy for surgical resection.  Patients are then stratified based on the surgical resection 
method chosen, number of positive lymph nodes, and margins to undergo adjuvant therapy with 
radiation or radiation with chemotherapy. For uterine neoplasms, specifically endometrial 
cancer, patients typically undergo an initial endometrial biopsy. If patient are medically operable, 
women will undergo a total hysterectomy, bilateral salpingo-oophorectomy, pelvic and/or 
paraaortic lymph node dissection, and potential debulking procedure if necessary. Similar to 
breast cancer, based upon the extent of disease noted these patients may then also go on to 
have adjuvant radiation with or without chemotherapy.  For cervical cancer patients, a majority 
of these neoplasms are detected by routine pap smears, followed by colposcopy with biopsy.  
For early stage disease, definitive conization or trachelectomy is the preferred management.  
For later stage disease, and for patients who refuse or cannot tolerate surgery, combination 
chemotherapy and radiation is the preferred treatment modality. 
 
Between the time of initial diagnosis (either radiographic or pathologic via biopsy) there is a 
planning period of on average 2-5 weeks. During this time period, subjects typically receive no 
active therapy. As described below, there is evidence to suggest that metformin with 
doxycycline might positively affect tumor cell biology and thereby affect cancer outcomes. We 
plan to give patients metformin and doxycycline prior to surgery in order to determine the 
physiological effects on cancer cells. If the results demonstrate that there is a positive effect, 
this will provide important supportive data for future clinical trials for cancer patients and could 
alter treatment approaches to patients.  
 
Metformin and Its Potential as an Antineoplastic Agent 
Metformin (N, N-dimethylbiguanide) is a biguanide that is best known for its use as first line 
therapy for type II diabetes patients (1). Metformin specifically inhibits the complex I 
(NADH:ubiquinone oxidoreductase) of the mitochondrial electron transport chain decreasing 
cellular respiration and the rate of ATP formation (2) (3) (4). This triggers the activation of the 
energy sensor AMP-activated protein kinase (AMPK) that regulates cell metabolism and shifting 
it towards an energy-sparing state (5). This leads to reduced hepatic glucose production, 
decreases intestinal absorption of glucose, and improves insulin sensitivity thereby increasing 
peripheral glucose uptake and utilization without causing hypoglycemia. It is an FDA approved 
medication for the management of type 2 diabetes mellitus with extensive safety data. In 
general, clinically significant responses are not seen at doses <1500 mg daily; however, a lower 
recommended starting dose and gradual increased dosage is recommended to minimize 
gastrointestinal symptoms.  
 
Extensive preclinical data now also supports the effectiveness of metformin as an antineoplastic 
agent (6).   
 
Epidemiologic Data for Metformin’s Efficacy: 

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Retrospective studies have shown that diabetics treated with metformin have a cancer risk 
reduction of approximately 40% compared to diabetics not treated with metformin (7,8). Other 
studies have also shown a reduction in the frequency of cancer with metformin use [33]. Evans 
et al (9) reported that the risk of subsequent cancer diagnosis was reduced in patients with type 
II diabetes who received metformin (with an odds ratio of 0.85 for any metformin exposure 
versus no metformin exposure). The protective effect increased with greater metformin 
exposure (measured as total dose prescribed or total duration of use).  
 
Current evidence from epidemiologic studies suggests that metformin has clinical activity in 
breast cancer.  Hadad et al (11) demonstrated biomarker evidence for anti-proliferative effects 
of metformin in women with breast cancer by decreasing Ki67 and messenger RNA expression 
for PDE3B (critical regulator of cAMP levels that affect activation of AMPK). Similarly, Niraula et 
al (12) showed short-term preoperative metformin with a dosing schedule of 500mg three times 
daily was well tolerated and resulted in clinical and cellular changes consistent with beneficial 
anti-cancer effects with increased insulin sensitivity by HOMA in subjects and decreased 
proliferation and increased apoptosis in carcinoma cells. 
 
Pre-clinical data also supports the potential benefit of metformin in patients diagnosed with 
cervical cancer.  Metformin was shown to induce apoptosis and autophagy in cervical cancer 
cells that express LKB1. LKB1 is responsible for the phosphorylation and activation of AMPK, 
which is a potent suppressor of cell proliferation in a variety of cell types, including cervical 
cancer cells.  While LKB1 intact cervical cancer cells showed the greatest response to 
metformin via LKB1-AMPK-mTOR signaling, it was shown that cervical cancer cells lacking 
LKB1 were less sensitive to the medication.  However, introducing ectopic expression of LKB1 
in these cells restored the sensitivity to metformin, which confirms the importance of LKB1 
expression in the use of metformin (89). 
 
There are currently multiple completed and on-going clinical trials evaluating the effect of 
metformin in combination with standard treatment of a variety of malignancies including breast, 
colorectal, pancreatic, lung, gynecologic, and prostate cancer (13, 14, 15).   
 
Mechanism of Action for Metformin and Doxycycline: 
Metformin has been proven to inhibit cell proliferation in vitro and/or in vivo in several 
malignancies (17)). Metformin in vivo has antineoplastic activity. Experimental work including in 
vivo experiments and clinical trials have demonstrated that metformin has anticancer properties 
(18)) (19) (20). The mechanism by which metformin has anticancer effects is unknown and the 
purported mechanisms are numerous and include OXPHOS complex I inhibition, AMPK 
activation and insulin growth factor signaling (21) (22) (23) (24). While the precise anticancer 
mechanisms are still an active area of research, metformin works overall by inducing energetic 
stress. One proposal for how this is accomplished is by its direct inhibitory effect on 
mitochondrial complex I. Several groups have shown that metformin’s ability to limit tumor 
growth in vivo is dependent on mitochondrial complex I (25). Complex I inhibition blocks 
mitochondrial-dependent production of reactive oxygen species (ROS) and adenosine 
triphosphase (ATP) (26-28).  Catabolite access may determine metformin susceptibility and as 
supporting examples, cancer cells grown in the absence of glucose and presence of glutamine 
are more affected by metformin treatment than cells grown in the presence of glucose (29). 
Metformin sensitivity is determined by glucose availability and oxidative phosphorylation 
(OXPHOS) capacity(30). The decrease in ATP production results in the activation of the liver 
kinase B1 (LKB1) – adenosine monophosphate-activated protein kinase (AMPK) signaling 
pathway (26-28).  Activation of this pathway usually occurs during times of hypoxia and nutrient 

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deprivation, and reciprocally, it can be suppressed in times of “over nutrition” and 
hyperglycemia.  AMPK is a key energy sensor that regulators metabolism in an attempt to 
maintain energy homeostasis (31). The end result of blocking the LKB1-AMPK signaling 
pathway is a down-regulation of energy consuming biosynthetic processes including 
gluconeogenesis, protein and fatty acid synthesis and cholesterol biosynthesis, and promotion 
of catabolic processes such as fatty acid beta oxidation and glycolysis (32). Metformin may also 
have activity that is independent of LKB1.  In LKB1 deficient cells, metformin is still able to affect 
the intracellular energy state (33). Metformin also alters the mitochondrial redox state by 
inhibiting glycerophosphate dehydrogenase (34). Metformin reduces the mitochondrial citric acid 
cycle and induces aerobic glycolysis as well(35).  
 
 
Figure 1.  The proposed mechanism of action of metformin in the cell [36]. 
 
Another central signaling molecular impacted by metformin is mammalian target of rapamycin 
(mTOR). In mouse embryonal fibroblasts and several cancer cell lines, AMPK activation by 
metformin leads to inhibition of mTOR and inhibition of proliferation (37-39). 
 
In addition to the effects of metformin and AMPK on metabolic processes, activation of AMPK 
results in rapid inhibition of cellular protein synthesis and growth. Mechanistically, AMPK 
achieves this by phosphorylation and stabilization of the protein product of the tuberous 
sclerosis complex tumor suppressor gene TSC2, which serves as an integrator of various 
regulatory inputs implicated in cell growth and transmits them to the master regulator of cellular 
protein synthesis, mTOR. In addition to mediating the inhibitory effects of AMPK on protein 
synthesis, TSC2 integrates several regulatory inputs that affect cellular protein translation, 
notably signals emanating from the availability of oxygen and growth factor– dependent 
stimulation of the phosphoinositide 3-kinase(PI3K)/phosphatase and tensin homolog(PTEN)/v-
akt murine thymoma viral oncogene homolog (AKT) and the Ras/Raf/extracellular signal-
regulated kinase (ERK) pathways, two of the most frequently deregulated signaling cascades in 
human cancer. Metformin has been shown to selectively target stem cells and to have 
synergistic properties with doxorubicin, paclitaxel and carboplatin allowing for conventional 
chemotherapy dose reductions in several carcinoma subtypes (40,41). Rozengurt et al identified 
crosstalk between insulin/insulin-like growth factors (IGF-1) receptors and G protein-coupled 
receptors (GPCR) signaling systems in pancreatic cancer cells leading to enhanced signaling, 
DNA synthesis, and proliferation. This crosstalk was dependent on mammalian target of 
rapamycin complex 1 (mTORC1). They were able to use metformin, which negatively regulates 

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mTORC1, and disrupt crosstalk between insulin/IGF-1 receptors and GPCR signaling inhibiting 
growth of pancreatic cancer cell lines in xenograft models. Therefore, metformin decreases 
oxidative phosphorylation (OXPHOS) metabolism and generation of reactive oxygen species 
(42).  
 
Other agents are also able to affect mitochondria. In contrast to the mechanism of action of 
metformin, doxycycline inhibits mitochondrial translation and mitochondrial OXPHOS. The 
translation machinery of mitochondria is distinct from that found in the cytosol and in bacteria 
although there are also similarities which make it a promising anticancer drug target. Eukaryotic 
cells originate from a merger of two formerly independent cells—the host cell and the α-
proteobacteria, which is a precursor of mitochondria. Each one of these cells contributed a 
protein synthesis system and hence eukaryotic cells have cytoplasmic and mitochondrial protein 
translation systems (43). Host cell translation, which occurs in the cytosol, synthesizes almost 
all cellular proteins, including most mitochondrial proteins. However, 13 key subunits of 
mitochondrial OXPHOS are mitochondrially translated. Up-regulation of mitochondrial 
translation occurs with the development of cancer in a subset of human malignancies (44). 
Inhibition of mitochondrial protein translation also has anticancer activity. 
 
Human mitochondrial ribosomes (mitoribosomes) are composed of a large 39S ribosomal 
subunit and a small 28S subunit, and by contrast, are highly specialized for the synthesis of 13 
membrane proteins in humans that function in energy production (45).  Advances in high-
resolution cryo–electron microscopy have proven that the molecular structure of mitoribosomes 
differs dramatically from the “canonical” cytosolic ribosome of bacteria and eukaryotes(44, 46). 
Also, the structures of mitoribosomes from different species are dramatically different(45). 
Human mitoribosomes have increased protein mass compared to bacterial ribosomes, which 
results in a ribosome with a more extensive protein-protein network and an rRNA core better 
shielded from ROS. This has important implications to develop anticancer drugs that specifically 
target mitoribosomes (46). The human small mitochondrial 28S ribosomal subunit shares 
features with the bacterial 30S subunit. As detailed atomic structures of human mitochondrial 
ribosomes are obtained, this should allow the rational design of compounds that specifically 
block mitochondrial ribosome activity. 
 
Doxycycline, which inhibits mitochondrial ribosome function, eradicates tumors and specifically 
CSCs, across many different tumor subtypes including breast cancer (47). Clinical trials are 
ongoing to determine if tetracyclines can be repurposed as anticancer agents.  
 
Preclinical Data in the Martinez Laboratory: 
We and others have shown that breast and uterine cancers have multi-compartment 
metabolism with high mitochondrial metabolism in carcinoma cells and high glycolytic 
metabolism in stromal cells. We have also shown that loss of CAV1 in the stroma is a marker of 
this metabolic heterogeneity. Metformin can rescue CAV1 expression experimentally and 
abolish metabolic heterogeneity in breast cancer. 
 
Cancer cells have the ability to metabolically reprogram non-cancerous surrounding cells in 
order to favor nesting behavior, derive nutrients, enhance proliferation, and eventually promote 
invasion and metastasis (48-51). This parasitic relationship between cancer cells and stromal 
cells is known as “two-compartment tumor metabolism” (52). In this context, cancer cells rely on 
oxidative metabolism in order to support their high bioenergetic requirements (53). 
Simultaneously, the remodeled cancer-associated stroma adopt a catabolic phenotype to 
provide catabolites to the anabolic cancer cells driving tumor-stroma co-evolution(54). The 

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presence of CAFs performing aerobic glycolysis is an important feature of multi-compartment 
metabolism and loss of stromal CAV1 is a marker of this process(48) (55). 
 
Loss of Caveolin-1 (CAV1) in CAFs is sufficient to drive the glycolytic phenotype in the stromal 
compartment and the increased mitochondrial metabolism in cancer cells (56). CAV1 is the 
principal structural protein coating caveolae in the plasma membrane, and functions as a 
scaffolding protein regulating signaling transduction. Downregulation of CAV1 in CAFs induces 
signaling through transforming growth factor beta (TGF-B), nuclear factor kB (NF-kB), and 
hypoxia inducible factor (HIF), triggering reactive oxygen reactive species (ROS) generation, 
inflammation, autophagy and increased catabolism (57). Reduced CAV1 expression overall 
drives a myofibroblast-like phenotype of CAFs that promotes tumor formation and progression 
and facilitates invasion and metastasis (56). Loss of CAV1 in CAFs is sufficient to induce further 
CAV1 downregulation in adjacent fibroblasts without requiring the presence of cancer cells (58). 
Clinically, loss of stromal CAV1 expression is associated with poor outcomes/prognosis in 
several cancer types including breast cancer (59, 60) squamous esophageal cancer (61), 
gastric cancer (62), colorectal cancer (63), pancreatic cancer (64), prostate cancer (66), non-
small cell lung cancer (66) and malignant melanoma (67).  
 
In head and neck squamous cell carcinomas (HNSCC) there are very similar features of 
metabolic heterogeneity to that observed in breast and endometrial cancer. HNSCC have high 
mitochondrial OXPHOS metabolism in highly proliferative cells (68). Also, there is low 
expression of CAV1 and high MCT4 expression in HNSCC cancer associated fibroblasts 
(CAFs) and in carcinoma cells with low proliferation rates (69). MCT4 expression is a marker of 
pseudohypoxia, oxidative stress and enhanced glycolytic metabolism. We have demonstrated 
that there is metabolic coupling between highly proliferative carcinoma cells with high OXPHOS 
metabolism and low proliferative carcinoma cells and fibroblasts (68). 
 
We interrogated HNSCC specimens to examine if different metabolic and oxidative stress 
compartments co-exist in human tumors.  A panel of biomarkers 
(Ki67/TOMM20/COX/MCT1/CAV1/MCT4) was employed to visualize metabolic 
compartmentation.  Three metabolic compartments were delineated: 1) proliferative and 
mitochondrial-rich carcinoma cells (Ki67+/TOMM20+/COX+), 2) non-proliferative and 
mitochondrial-poor carcinoma cells (Ki67-/TOMM20-/COX-), and 3) non-proliferative and 
mitochondrial-poor tumor stroma  (Ki67-/TOMM20-/COX-/CAV1-).  High oxidative stress 
(MCT4+) was specific for cancer tissues. 
 
With this data, we then evaluated its prognostic value in a second cohort (N=40). We found that 
oxidative stress (MCT4+) in non-proliferating carcinoma cells predicted poor clinical outcome (p 
< 0.001), and was functionally associated with PET-avidity (p <0.04). Similarly, oxidative stress 
(MCT4+) in tumor stromal cells was associated with higher tumor stage (p < 0.04). Leading us 
to propose that oxidative stress is a hallmark of tumor tissues and fuels mitochondrial 
metabolism in proliferating mitochondrial-rich cancer cells, via paracrine energy transfer of 
mitochondrial fuels (such as L-lactate and ketone bodies). 
 
With this, we were able to show for the first time that metabolic and oxidative stress 
compartmentalization exists in HNSCC mucosa with highly proliferative epithelial cancer cells 
having high mitochondrial metabolism with lactate and ketone body uptake while as other 
carcinoma cells and CAFs have low mitochondrial metabolism with high lactate and ketone 
body generation and high oxidative stress. This metabolic and oxidative stress 
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likely drives proliferation via OXPHOS metabolism. MCT4 is an oxidative stress marker and may 
be a marker of CAFs since it is always absent in normal fibroblasts while it is found in the 
majority of CAFs. A subgroup of HNSCC has high MCT4 expression in a large carcinoma 
compartment and this subtype is associated with a poor prognosis.  
 
Furthermore in a pilot trial looking at the effects of metformin on mitochondrial metabolism in 
HNSCC patients, we have already shown that after an average of 14 days of exposure to 
metformin as a single agent the average expression of Caveolin-1 was increased from 17% pre-
treatment to 60% post- metformin exposure. Analyses from this trial are currently underway. 
 
 
Doxycycline 
 
Doxycycline is a tetracycline antibiotic commonly used to treat non-gonococcal urethritis, 
respiratory tract infections, and acne vulgaris among other bacterial infections (69). It is 
generally bacteriostatic and affects both gram-positive and gram-negative bacteria by 
transportation into the cell via passive diffusion or through an energy-dependent active transport 
system. Doxycycline is relatively more lipophilic than other tetracyclines, allowing easy passage 
through the bacterial lipid bilayer into the cytosol, where reversible binding to the 30S ribosomal 
subunit occurs; this ultimately inhibits bacterial protein synthesis. High concentrations of 
antibiotic can also interfere with protein synthesis in mammalian cells, but these cells lack the 
active transport systems found in bacteria, making eukaryotic cells less vulnerable targets 
(Clinical Key). 
 
Given that mitochondria have a bacterial ancestry and that the 30S bacterial ribosomal subunit 
is homologous to the 28S mitochondrial subunit (70), these antibiotics also target mitochondrial 
translation and impair mitochondrial function. Doxycycline in particular disturbs mitochondrial 
protein synthesis and metabolic activity while altering gene expression (71). Even at low 
concentrations, it has been shown to increase glycolytic metabolism and markedly reduce 
mitochondrial oxygen consumption (72). The crystalline structure of mitochondrial proteins also 
plays an important role in the efficacy of various drugs on altering mitochondrial metabolism. 
Lee et al. reported that the target protein in cancer cell mitochondria is TNF receptor-associated 
protein 1 (TRAP1), and TRAP1 inhibitor efficacy depends on the degree of fit between the 
crystalline structure of TRAP1 and the structural conformation of the drug in question. This 
effect of tetracyclines on mitochondrial metabolism is highly relevant for cancer research. 
 
Doxycycline, with its long half-life systemically, has recently become an attractive anti-neoplastic 
agent. It also encourages the growth of normal stem cells, has anti-inflammatory properties, and 
even increases lifespan, in certain experimental contexts (73,74). In tumor xenografts and other 
animal models, doxycycline significantly reduces tumor burden and metastatic cancer cell 
growth (75). Further studies are needed to elucidate doxycycline’s anti-neoplastic properties 
and support its clinical application in cancer treatment. 
 
Combination of Metformin and Doxycycline for Treatment: 
Metformin and doxycycline work through independent mechanisms to block mitochondrial 
metabolism.  We hypothesize that these two FDA-approved medications will be able to provide 
and additive effect when used in combination to alter the cellular metabolism of cancer cells and 
their associated stromal fibroblasts. 
 

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Our preliminary work in head and neck squamous cell carcinoma has already shown that 
metformin alone modulates the expression of CAV1 in cancer-associated fibroblasts. We 
hypothesize that metformin and doxycycline together will be able to increase Caveolin-1 
expression in cancer-associated fibroblasts as well as to decrease stromal MCT4 expression 
and carcinoma TOMM20 expression with altered metabolite profiling. The ability to more fully 
understand and to modify the metabolic profile of cancer associated fibroblasts may lead to 
future therapies in breast, uterine (endometrial), and cervical cancers. 
 
 
1.2 Rationale  
Metformin, a widely used anti-diabetic drug, which functions as a mitochondrial inhibitor, can 
also be used to selectively target cancer stem cells. Metformin functionally inhibits OXPHOS by 
targeting complex I of the electron transport chain and can even induce lactic acidosis, as a 
lethal side effect (76). As a result, the use of antibiotics, such as doxycycline, may provide a 
safer and far more effective alternative to anti-cancer therapy with high metformin doses. Thus, 
future clinical trials for testing the efficacy of mitochondrial-targeted antibiotics in multiple cancer 
types are now clearly clinically warranted. 
 
Doxycycline is a broad-spectrum antibiotic that is commonly used for the treatment many 
bacterial infections, and functions as an inhibitor of protein synthesis in bacteria. Doxycycline 
also encourages the growth of normal stem cells, has anti-inflammatory properties, and even 
increases lifespan, in certain experimental contexts (77,78). Thus, the toxic side effects of anti-
cancer therapy would be minimized. Doxycycline has also been used in human tumor 
xenografts and other animal models to significantly reduce tumor burden and even metastatic 
cancer cell growth (79-82). For example, in pancreatic tumor xenografts (with PANC-1 cells), 
doxycycline treatment reduced tumor growth by ~80% (83). In a xenograft model of breast 
cancer bone metastasis (with MDA-MB-231 cells), doxycycline treatment reduced bone and 
bone-associated soft-tissue tumor mass by >60% and ~80%, respectively (84). 
 
Overall, we hypothesize that the combination of metformin and doxycycline will co-target 
mitochondrial pathways and possibly be synergistic in impairing mitochondrial function that 
could lead to further cell quiescence. 
 
Hypothesis: Exposure to metformin and doxycycline administered together will alter the 
metabolic profile of solid tumor malignancies, specifically with respect to breast, uterine and 
cervical cancers. 
 
Rationale for Dosage/Route of Administration 
Metformin will be administered orally since this is the route of administration currently approved 
by the FDA. The drug will be initiated at a dose of 500mg daily with dose escalation every 3 
days to a goal of 1000mg twice daily to be continued until the time of definitive surgery. There 
are currently multiple studies on-going using doses from between 500 mg twice daily up to 2500 
mg per day in the treatment arms. There are also studies using the extended release form for a 
dose of 1500 mg daily. We have chosen our starting dose and escalation regimen to minimize 
side effects. The chosen standing dose is based on metformin’s therapeutic range (minimal 
therapeutic dose in diabetic patients is 1500-2000 mg a day) (85,86). The minimum time of 
planned exposure to metformin will be 7 days and the maximum planned exposure will be 35 
days (average time at TJUH from cancer diagnosis to definitive surgical treatment is 3 weeks). 
We will allow a window of a 1-5 weeks in the event that there are delays in the surgical 
scheduling but no patients will receive metformin for more than 35 days. 

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The usual dose of oral doxycycline is 200 mg on the first day of treatment (administered 100 mg 
every 12 hours) followed by a maintenance dose of 100 mg/day. The maintenance dose may be 
administered as a single dose or as 50 mg every 12 hours. In the management of more severe 
infections (particularly chronic infections of the urinary tract), 100 mg every 12 hours is 
recommended. The study will be administering 200 mg of doxycycline, given as 100 mg every 
12 hours until the day prior to surgery.  
 
Rationale for endpoints 
Primary: We have chosen Caveolin-1 expression in tumor stroma as our primary endpoint 
based on studies revealing that CAV1 stromal expression modulates tumor growth in animal 
models, is a prognostic biomarker and preliminary analyses of a pilot study conducted in head 
and neck squamous cell carcinoma.  Immunohistochemistry for CAV1 in the tumor-associated 
stroma will be compared in the pre-treatment specimen and the post-treatment specimens.  All 
stained specimens will be independently viewed and scored by two pathologists who are 
blinded as to the nature of the samples and specifically as to whether the tissue is pre or post-
metformin/doxycycline treatment as previously described by the investigators (68). The stained 
sections will be scored taking into consideration the intensity of staining and the percentage of 
stained cells within each tissue core.  
 
Secondary: We have chosen MCT1, MCT4, and TOMM20 as secondary end-points of the 
current clinical trial due to their biologic and prognostic significance seen in our work in head 
and neck squamous cell carcinoma. MCT4 expression in fibroblasts is associated with 
advanced stage disease.  MCT1 and TOMM20 expression in carcinoma cells is associated with 
increased functional mitochondrial mass. Prior work in our laboratory has suggested a 
correlation between MCT1 expression in breast cancer samples and the Estrogen Receptor 
(ER), Progesterone Receptor (PR) and HER2 status of the tumors.  We will seek similar 
correlations here. 
 
Correlative: Mass spectroscopy imaging (MSI) will be performed on paired samples from the 
three subjects, comparing metabolite profiles including ATP, hexose bisphosphates, lactate and 
pyruvate in the pre-treatment and post-treatment tumor sample. MSI will allow spatial 
characterization of the metabolic profile of carcinoma and stromal cells within the tumor. MSI will 
also allow us to determine if distance between carcinoma and stromal cells is associated with 
different metabolite profiles.  MSI testing will be performed at Vanderbilt University as has been 
performed in the ongoing metformin HNSCC. This testing is performed outside of the KCC 
because we lack the facilities and expertise for MSI.  We will also send tumor samples from our 
tumor bank, from patients who have not taken metformin or doxycycline, to use as controls.  We 
will also further characterize the baseline metabolic state of the patient by performing, when 
possible, a nutritional assessment via a nutritionist-mediated 3 day dietary recall and comparing 
a patient’s estimated dietary intake against their estimated caloric needs calculated with the 
Harris-Benedict equation. This will determine if patients are already calorically restricted, a 
phenotype similar to that of mitochondrial blockade.  Similarly we will do a serologic assessment 
of their metabolic state will also be performed at the time of enrollment and at the time of 
resection using the serum markers oncomiR-21, triglycerides, IGF-1, IGF-BP3, ESR, IGFR-1, 
exosomes, metabolomics, and microRNA expression profiles.  These serologic assays have 
been shown to correlate both with nutritional state and in the case of miR21 with tumor burden. 
 
1.3 Correlative Studies 

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Mass spectroscopy imaging (MSI) will be performed on paired samples, comparing relative 
proportion of metabolite profiles (specifically ATP, hexose bisphosphates, lactate and pyruvate) 
in the pre-treatment and post-treatment tumor sample. MSI allows assessment of metabolite 
levels in spatially defined tumor regions (87) and hence will allow the evaluation of metabolite 
levels in carcinoma and stromal cell compartments. 
 
To begin to estimate the patient’s baseline metabolic state, we will also try to perform a 
nutritional assessment via a nutritionist-mediated 3 day dietary recall and comparing a patient’s 
estimated dietary intake against their estimated caloric needs calculated with the Harris-
Benedict equation.  Patients will be characterized as not meeting, meeting, or exceeding their 
caloric needs.   
   
A serologic metabolic profile will be built using oncomiR-21, triglycerides, IGF-1, IGF-BP3, ESR, 
IGFR-1, exosomes, and metabolomics and seeking to correlate this with the patient’s CAV1 
expression levels and baseline and after intervention. 
 
The immunohistochemistry markers described above in the primary and secondary objectives, 
as well as the MSI and serologic profiling will all also be correlated with the %of cancers cells 
that stain or estrogen receptor and progesterone receptor for each of the cancer types.  
Furthermore breast cancer samples will also be assessed for their expression of HER2 via IHC 
and FISH. 
 
1.4 Potential Risks and Benefits 
1.4.1 Potential Benefits 
Metformin 
The possible societal benefits are large since this will allow us to learn about the 
pharmacodynamic effects of metformin and doxycycline in breast, uterine, and cervical cancers.  
Information about the expression levels of CAV1, MCT4, MCT1, TOMM20, and the 
metabolomics described above will also more broadly allow us to gain new information on tumor 
metabolism.  The study is designed to study as a primary end-point metformin and doxycycline’s 
effects on expression of CAV1 but not to study if this combination of agents improves outcomes 
as a primary end-point and hence it is unlikely to have significant clinical benefits for subjects 
with breast, uterine or cervical cancer.  
 
Doxycycline 
Doxycycline is relatively attractive as a new anti-cancer agent, as it has a long half-life 
systemically and has been used successfully for the long-term treatment of patients with urinary 
tract infections (UTI), prostatitis or acne, for extended periods of time, of up to 4-to-6 months or 
more (200 mg per day). Doxycycline also encourages the growth of normal stem cells, has anti-
inflammatory properties, and even increases lifespan, in certain experimental contexts.  Thus, 
the toxic side effects of anti-cancer therapy would be minimized. 
 
1.4.2 Potential Risks 
Metformin 
Metformin’s most serious toxicity is lactic acidosis, occurring in three of 100,000 patient-years of 
use. Risk is significantly reduced when metformin use is avoided in those patients with hepatic, 
cardiac, or renal compromise. However, metformin’s risk of lactic acidosis may be overstated 
since the recent evaluation of metformin associated lactic acidosis cases from 347 trials showed 
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other antiglycemic agents (88). Minor gastrointestinal upset is the most common toxicity, leading 
to cessation of therapy in less than 5% of individuals. Metformin does not induce hypoglycemia.  
 
Doxycycline 
Due to oral doxycycline’s virtually complete absorption, side effects to the lower bowel, 
particularly diarrhea, have been infrequent. The following adverse reactions have been 
observed in patients receiving tetracyclines:  
 
Gastrointestinal: Anorexia, nausea, vomiting, diarrhea, glossitis, dysphagia, enterocolitis, and 
inflammatory lesions (with monilial overgrowth) in the anogenital region. Hepatotoxicity has 
been reported rarely. These reactions have been caused by both the oral and parenteral 
administration of tetracyclines. Rare instances of esophagitis and esophageal ulcerations have 
been reported in patients receiving capsule and tablet forms of drugs in the tetracycline class.  
Skin: Maculopapular and erythematous rashes. Exfoliative dermatitis has been reported but is 
uncommon.  
 
Hypersensitivity reactions: Urticaria, angioneurotic edema, anaphylaxis, anaphylactoid purpura, 
serum sickness, pericarditis, and exacerbation of systemic lupus erythematosus.  
Thyroid Gland Changes: When given over prolonged periods, tetracyclines have been reported 
to produce brown- black microscopic discoloration of thyroid glands. No abnormalities of thyroid 
function are known to occur.  
 
Combination of these Agents: 
No drug-drug interactions are known to occur between these two agents. Metformin is not 
metabolized and is excreted unchanged in the urine with a half-life of approximately 5 hours.  
Similarly, doxycycline is not significantly metabolized and no metabolites have been found in 
man. Some studies have suggested a potential hepatic metabolism pathway. However, no 
excess toxicity is expected from the combination of these two agents and thus no additive 
potential harm beyond those associated with the individual agents as described above. 
2 Study Objectives 
2.1 Objectives 
2.1.1 Primary 
• 
To determine if treatment with a combination of metformin and doxycycline can increase 
the percentage of cells that express Caveolin-1 in the cancer associated fibroblasts of 
patients with breast, uterine, or cervical cancers. 
2.1.2 Secondary 
• 
To determine the effect of metformin and doxycycline treatment on the percentage of 
cells that express MCT4 in cancer associated fibroblasts and MCT1 and TOMM20 in the 
cancer cells of breast, uterine and cervical cancer patients. 
• 
To assess safety and tolerability of metformin and doxycycline treatment in subjects with 
breast, uterine and cervical cancer. 
• 
To determine the relationship of the percentage of stromal cells expressing CAV1 or 
MCT4 and tumor cells that express MCT1 and TOMM20 at baseline and after treatment 

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with metformin and doxycycline with the percentage of cells expressing ER and PR for 
breast, uterine and cervical samples and HER2 in breast cancer samples. 
2.1.3 Correlative 
• 
To assess the effect of combined metformin and doxycycline therapy on the metabolic 
profile of cancer cells and stroma using mass spectroscopy imaging (MSI) on paired 
samples, comparing metabolite profiles in the pre-metformin and post-metformin tumor 
sample.  
• 
To assess, when possible, the impact of a patient’s nutritional status, estimated using 3-
day dietary recall versus caloric needs as calculated by the Harris-Benedict equation on 
the baseline and net change in CAV1. 
• 
To assess the effect of combined metformin and doxycycline therapy on oncomiR miR-
21 after intervention. 
• 
To assess the effect of combined metformin and doxycycline therapy on adipokines and 
the IGF-1/insulin signaling pathways through assessment of serum triglycerides, IGF-1, 
IGF-BP3, erythrocyte sedimentation rate (ESR), adiponectin, leptin, IGF-1R, exosome 
evaluation, metabolomics profile, and microRNA expression profile. 
 
2.2 Endpoints/Outcome Measures 
2.2.1 Primary 
• 
Assess the change in the percent of stromal cells expressing CAV1 at an intensity of 1+ 
or greater after treatment with metformin and doxycycline as determined by two blinded 
pathologists. 
2.2.2 Secondary 
• 
Assess safety and tolerability of metformin and doxycycline treatment in subjects with 
cancer. Toxicity will be evaluated using the most recent version (version 4.03) of the NCI 
toxicity criteria, i.e. the NCI Common Terminology Criteria for Adverse Events (CTCAE) 
version 4.03.  
• 
Assess the change in the percent of stromal cells expressing express MCT4 and the 
percent of tumor cells that express MCT1 and TOMM20 in the cancer cells of breast, 
uterine and cervical cancer patients using Aperio analyses of expression intensity with 
previously validated algorithms. 
• 
Assess the relationship of the percentage of stromal cells expressing CAV1 or MCT4 
and tumor cells that express MCT1 and TOMM20 at baseline and after treatment with 
metformin and doxycycline with the percentage of cells expressing ER and PR for 
breast, uterine and cervical samples and HER2 in breast cancer samples. 
3 Study Design 
This is a 2 parallel cohort Phase II study. Metformin and doxycycline are the therapeutic agents.  
For metformin, the initial starting dose will be 500 mg orally daily for 3 days which will then be 
increased to 500 mg orally twice daily for 3 days, and if tolerated, further increased to 1000 mg 
twice daily after day 6.  Subjects will maintain the maximum tolerated dose (up to 1000 mg twice 
daily) until the day prior to their scheduled definitive surgery. All medications should cease at least 
12 hours prior to time of surgery. 

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For doxycycline the patients will take 100 mg by mouth every twelve hours until the day prior to 
their surgery. The last dose should be taken no closer than 12 hours prior to time of surgery. 
 
Table 1. Study Design  
 
Eligibility Screening 
Cohort Treatment Week 
-1 
1 
2 
3 
4 
5 
Day 
-1 
1 
2 
3 
4 
5 
6 
7 
8* 
9 
10 
11 
12 
13 
14 
 
1 
N=23 
Doxycyclinee 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Surgical 
Resection 
Metformin 
 
Xa 
Xa 
Xa 
Xb 
Xb 
Xb 
Xc 
Xc 
Xc 
Xc 
Xc 
Xc 
Xc 
Xc 
2 
N= 
23 
Doxycyclinee 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Metformin 
 
Xa 
Xa 
Xa 
Xb 
Xb 
Xb 
Xc 
Xc 
Xc 
Xc 
Xc 
Xc 
Xc 
Xc 
 
Tissued 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
X 
 
* If surgery is scheduled past Day 8, patients will stay on metformin and doxycycline until the day prior to surgery. 
a. 
Metformin will be given initially with a starting dose of 500mg once a day for Days 1-3. 
b. 
Metformin will be increased to 500 mg orally twice a day for Days 4-6 
c. 
If tolerated, beginning Day 7 metformin will be increased to 1000 mg twice a day. Subjects will maintain the 
maximum tolerated dose (up to 1000 mg twice daily) until the day prior to their scheduled definitive surgery. 
d. 
When possible, baseline biopsy tissue is to be obtained prior to starting study medications.  Two serum 
separator tubes of serum will be taken at the same time as the biopsy specimen (if possible), otherwise 
done at time of consent.  If a pre-treatment sample has already been acquired and flash froze and if there is 
excess tissue available at resection, the second  specimen will also have a piece flash frozen for 
metabolomic testing. 
e. 
Doxycycline will be taken once every 12 hours, with the last dose being taken at least 12 hours prior to 
scheduled time of definitive surgery. 
 
 
 
Eligibility Screening: Trial Coordinator will screen the office charts for possible inclusion in the 
trial. Labs for the screening part will be available from pre-admission testing that is standard of 
care for initial biopsy. Participants of child bearing potential will have a pregnancy test within 14 
days prior to enrollment. 
 
Visit 1, Day 0: Subjects that meet the inclusion criteria after reviewing diagnosis, laboratory data 
and clinical chart will be approached the day of their consult or follow up with a subspecialty 
surgeon. The study coordinator will meet with the prospective candidates and go over the 
protocol, answer questions and obtain informed consent. If the subject is agreeable to the study, 
two 8.5 mL vials of blood will be drawn for baseline metabolomics and exosome profiling. After 
eligibility is confirmed, metformin and doxycycline will be dispensed. Instructions on how to take 
study drug will be given and times for follow up phone calls for tolerability and safety will be 
arranged with participants. When possible, patients will be given the option to meet with a 
nutritionist either in person or by phone within the first 7 days of their enrollment to fill out a 3 
day dietary recall.  
 

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Visit 2,Day of Surgery: Patients will be approached for bottles and pill reconciliation as well as 
follow up of side effects and adverse events the day of final surgery. Two 8.5 mL vials of blood 
will be drawn for post-treatment metabolomic and exosome profiling. A specimen of the 
removed tumor will be taken for genomic analysis. 
 
Follow-up: A follow up phone call will be performed 30 days (+5 days) after the last dose of 
metformin and doxycycline for any other side effects or adverse events. The participant’s 
medical records will be reviewed every 3 months (+1 month) for 12 months to assess:  overall 
survival, frequency of metastasis, and staging. 
4 Study Enrollment and Withdrawal 
Patients must have baseline evaluations performed prior to the first dose of study drug and must 
meet all inclusion and exclusion criteria. Results of all baseline evaluations will be reviewed by 
the Principal Investigator or treating physician prior to enrollment, to verify that all inclusion and 
exclusion criteria have been satisfied. In addition, the patient must be thoroughly informed about 
all aspects of the study, including the study visit schedule and required evaluations and all 
regulatory requirements for informed consent. The written informed consent must be obtained 
from the patient prior to screening procedures being performed. The following criteria apply to 
all patients enrolled onto the study unless otherwise specified. 
4.1 Subject Inclusion Criteria 
In order to be eligible for participation in this trial, the subject must:  
1. Diagnosis of localized breast, uterine or cervical cancer that is either biopsy proven or 
suspected based on history, physical, and/or radiographic findings, and who are planned 
for definitive resection of the tumor without the use of neoadjuvant chemotherapy or 
radiation therapy at TJUH are eligible to participate. 
2. Subjects must be ≥ 18 years of age at time of consent. 
3. Subjects must be newly diagnosed or suspected to have breast, uterine (endometrial 
cancer with histologies including endometrioid, serous, clear cell, and carcinosarcoma) 
or cervical cancer. 
4. Patient must be able to swallow pills.  
5. Patients with serum creatinine levels less than 1.5 mg/dL. 
6. Women of child bearing potential must have a negative urine or blood pregnancy test 
within 14 days of study enrollment. 
7. Informed Consent:  All subjects must be able to comprehend and sign a written informed 
consent document.  
8. ECOG Performance status <1 
4.2 Subject Exclusion Criteria  
The subject must be excluded from participating in the trial if the subject:  
1. Received any prior cancer therapy for the breast, uterine, or cervical cancer that is being 
resected, including progesterone therapy for endometrial cancer patients.   
a. Patients may have had prior therapy for other contra-lateral breast cancer. 
2. Subjects who are pregnant or breastfeeding or may become pregnant during metformin 
and doxycycline administration. 
3. Subjects on metformin or doxycycline for any reason during the preceding 4 weeks. 
4. Diabetic subjects that are managed by taking metformin or insulin.  
5. Subjects who have received iodinated contrast dye must wait 12 hours prior to starting 
Metformin. If a CT scan with contrast is scheduled after screening and consent, the 

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metformin cannot be taken until after the CT with contrast has been completed and they 
have waited 12 hours. 
6. Patients with serum creatinine level greater than 1.5 mg/dL. 
7. Patients with history of lactic or any other metabolic acidosis.  
8. Patients with history of congestive heart failure stage III or greater. 
9. Patients scheduled for definitive cancer surgical resection less than 7 days from 
beginning of study drug administration or greater than 5 weeks from beginning study 
drug administration.  
10. Patients with history of hepatic dysfunction or hepatic disease and abnormal liver 
function tests defined as AST, ALT, Alk Phos, and or total bilirubin greater than 2.5 times 
the upper limit of normal.   
a. Patients who have a history of hepatic dysfunction or hepatic disease and normal 
liver function tests will be eligible to participate. 
11. Patients with a current history (in the past 30 days) of heavy drinking which is defined in 
accordance with CDC definition as more than 8 drinks per week for women and more 
than 15 drinks per week for men. A standard drink contains .6 ounces of pure alcohol. 
Generally, this amount of pure alcohol is found in 12-ounces of beer, 8-ounces of malt 
liquor, 5-ounces of wine, 1.5-ounces or a “shot” of 80-proof distilled spirits or liquor (e.g., 
gin, rum, vodka, or whiskey). While on study, patients should limit their alcohol 
consumption to no more than 8 drinks per week for women and no more than 15 drinks 
per week for men. Patients who feel they cannot comply with this recommendation are 
not eligible. Prior allergic reaction to metformin, doxycycline, or any other tetracycline 
antibiotic in the past.  
12. Patient is on medications that are contraindicated with metformin or doxycycline under 
current FDA recommendations.  The following is a list of medications identified as class 
D (consider therapy modification) when treatment with metformin or doxycycline is 
considered: 
o Class D: 
 
Bismuth Subsalicylate 
 
Cimetidine  
 
Iodinated contrast agents 
 
Somatropin 
 
4.3 Gender/Minority/Pediatric Inclusion for Research 
We will not exclude potential subjects from participating in this study based on ethnic origin or 
socioeconomic status.  Every attempt will be made to enter all eligible patients in this protocol 
and therefore address the study objectives in a patient population representative of the entire 
breast, uterine and cervical cancer population treated at Thomas Jefferson University Hospital.  
By the nature of the diseases covered in this trial the majority enrolled will be female.  We will 
not exclude male patients with breast cancer. 
 
4.4 Recruitment and Screening 
46 subjects will be recruited. No advertisement will be conducted. Screening requirements 
include serum measurement of creatinine, aspartate aminotransferase, alanine 
aminotransferase and alkaline phosphatase taken on a non-fasting blood sample. Potential 
research subjects will be identified by a member of the patient’s treatment team, the protocol 
investigator, or research team at participating centers from Medical Oncology, Radiation 
Oncology and Surgical offices. Investigators will screen the patient’s medical records for 
suitable research study subjects and discuss the study and their potential for enrolling in the 

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research study. Patients will be screened based on pathology, image studies etc. A maximum of 
23 patients will be enrolled onto each arm of the trial (see Statistical Analysis Plan Section 9).  
 
4.5 Subject Withdrawal/Discontinuation Criteria 
Subjects may withdraw consent at any time for any reason or be dropped from the trial at the 
discretion of the investigator should any untoward effect occur. In addition, a subject may be 
withdrawn by the investigator or the Sponsor if enrollment into the trial is inappropriate, the trial 
plan is violated, or for administrative and/or other safety reasons.  
Subjects may be discontinued from the trial for any of the following reasons: 
• 
The subject withdraws consent. 
• 
Documented Disease progression  
• 
Unacceptable adverse experiences as described in Section 8 
• 
Investigator’s decision to withdraw the subject 
• 
Noncompliance with trial treatment or procedure requirements 
• 
The subject is lost to follow-up 
• 
Administrative reasons 
 
The End of Treatment and Follow-up visit procedures are listed in Section 6 Trial Flow Chart.  
After the end of treatment, each subject will be followed for 30 days for adverse event and 90 
days for serious adverse events monitoring as (described in Section 8.4).  
 
4.5.1 Subject Replacement Strategy 
Patients who are discontinued from the study for any reason outlined in Section 4.5 will not be 
considered as evaluable for this study and will be replaced. 
 
5 Study Treatments 
5.1 Study Product  
The investigator shall take responsibility for and shall take all steps to maintain appropriate 
records and ensure appropriate supply, storage, handling, distribution and usage of 
investigational product in accordance with the protocol and any applicable laws and regulations. 
 
5.2 Study Product Description 
Metformin: 
Metformin is a biguanide drug currently approved for the treatment of type 2 diabetes mellitus by 
the FDA. It is currently being investigated in multiple cancer treatment trials.  
 
Metformin is the therapeutic agent in the protocol. The initial starting dose will be 500mg orally 
daily for 3 days which then will be increased to 500 mg twice daily and, if tolerated, further 
increased to 1000mg twice daily after day 6. Patients will maintain 1000 mg twice a day dosing 
until the day prior to their scheduled definitive surgery. This dose schedule has been shown to 
be well tolerated and was able to promote cellular changes consistent with beneficial anti-
cancer effects in breast cancer patients (32). 
 
The treatments to be used in this trial are outlined below in Table 2. Trial treatment should begin 
within 5 days of eligibility confirmation.  
 
Table 2         Trial Treatments 
  

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Drug 
Dose Level 
Dose 
Route of 
Administration 
Regimen 
Metformin 
-1 
500 mg QDay 
Orally 
Day 1-3 
1 
500 mg BID 
Day 4-6 
2 
1000 mg BID 
Day7- Day 
Before Surgery 
Doxycycline 
-1 
100 mg Q12 hours 
Orally 
Day 1- Day 
Before Surgery 
 
 
Doxycycline: 
Doxycycline is an antibiotic provided in the formulation doxycycline hyclate.  Doxycycline is 
virtually completely absorbed after oral administration.  Following administration of a single 200 
mg dose to adult volunteers, average peak serum doxycycline levels were 2.6 mcg/mL at 2 
hours, decreasing to 1.45 mcg/mL at 24 hours. The mean Cmax and AUC 0-∞ of doxycycline 
are 24% and 13% lower, respectively, following single dose administration of DORYX tablets, 
100 mg with a high fat meal (including milk) compared to fasted conditions. The mean Cmax of 
doxycycline is 19% lower and the AUC 0-∞ is unchanged following single dose administration 
of DORYX Tablets, 150 mg with a high fat meal (including milk) compared to fasted conditions. 
The clinical significance of these decreases is unknown. 
 
Tetracyclines are concentrated in bile by the liver and excreted in the urine and feces at high 
concentrations and in a biologically active form. Excretion of doxycycline by the kidney is about 
40%/72 hours in individuals with a creatinine clearance of about 75 mL/min. This percentage 
may fall as low as 1-5%/72 hours in individuals with a creatinine clearance below 10 mL/min.  
Studies have shown no significant difference in the serum half-life of doxycycline (range 18-22 
hours) in individuals with normal and severely impaired renal function. Hemodialysis does not 
alter the serum half-life.  
Doxycycline is an FDA approved product that is indicated for the prophylaxis against and 
treatment of both bacterial and protozoal infections.  For adults the dose is 200 mg on the first 
day of treatment administered as 100 mg every 12 hours followed by a maintenance dose of 
100 mg daily.  The maintenance dose may be administered as a single 100 mg dose of 50 mg 
dose every 12 hours.  Serious infections are treated with a sustained dose of 200 mg per day in 
divided doses. Treatment for uncomplicated bacterial infections typically lasts for 7 days total.  
Prophylaxis for malaria can be continued daily for the period of time the patient is in a malarious 
area and continued for 4 weeks thereafter, up to 4 months. 
5.2.1 Dose Calculation 
Rules for dose modification: Toxicity monitoring, dose modification and treatment of 
complications: 
Particular attention will be paid in the first three days of treatment. Patients will take 500mg/day 
for 3 days.  If tolerated, starting day 4, patients will increase to 500mg twice daily. If this dose 
increase is tolerated, then on day 7 the patient will be dose escalated to 1000mg twice daily.  
The maximum tolerated dose will be taken until the day before surgery with food.  A phone call 
on or around the day of each dose escalation (± 2 days) will be made in order to evaluate the 
tolerability of the drug and also weekly thereafter.  Patients will be instructed to contact the 
clinical investigators should any toxicity occur during the study (66). 
 

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Metformin will be held for 12 hours if CAT scan intravenous contrast is administered to decrease 
risk of lactic acidosis. This approach is more stringent than the most recent recommendation of 
the American College of Radiology which does not recommend holding metformin in the 
absence of comorbidities (renal insufficiency, liver dysfunction, alcohol abuse, cardiac failure, 
myocardial or peripheral muscle ischemia, sepsis or severe infection) which are exclusion 
criteria for this clinical trial (29).  
 
Toxicity will be evaluated using the NCI Common Terminology Criteria for Adverse Events 
(CTCAE) version 4.03.  
• 
Grade 1 toxicity: Patient will be maintained on full dose. 
• 
Grade 2 toxicity (probably or definitely drug related): Dose will be reduced back to the 
maximum tolerated dose until grade 1 or lower. If symptoms are not resolved within 3 
days the treatment will be discontinued definitively. 
• 
Grade 3 toxicity (probably or definitely drug related): Treatment will be interrupted and 
toxicity reassessed daily. If toxicity improves to grade 2, dose will be reduced back to the 
maximum tolerated dose. 
• 
Grade 4 toxicity (probably or definitely drug related): Treatment will be discontinued 
definitively. 
 
In case of grade 1 or 2 diarrhea (the most frequent side effect) a concomitant administration of 
loperamide may be provided, and dose may be reduced back to the maximum tolerated dose or 
temporarily halted at the treating physician’s discretion. Clear documentation of this will be 
recorded in the patient’s research chart. 
 
If patient experiences continued intolerable side effects, dose management may be discussed 
with a study investigator and dose modification can be recommended as needed. Clear 
documentation of this will be recorded in the patient’s research chart. 
 
If doses of either medication are missed due to toxicity they should not be replaced.  If a dose is 
not taken due to an error, it may be taken up to 6 hours later.  If vomiting occurs within 30 
minutes of intake, that dose may be repeated.  These events should be recorded by the patient 
on their pill diary. 
 
5.2.2 Packaging and Labeling Information 
Clinical supplies will be affixed with a clinical label in accordance with regulatory requirements. 
 
5.2.3 Clinical Supplies Disclosure 
The subject, the trial site personnel, the Sponsor and/or designee are not blinded to treatment. 
Drug identity (name, strength) is included in the label text; random code/disclosure envelopes or 
lists are not provided. 
 
5.2.4 Receiving, Compliance, Storage and Return 
Receipt of Drug Supplies 
Metformin and doxycycline tablets will be provided by the Department of Medical Oncology and 
will be coordinated through the Thomas Jefferson University Hospital Investigational Drug 
Service (IDS) Pharmacy. Drug will be stored in locked cabinet until given to the participants. A 
study investigator will prescribe the approximate amount of medication needed for the treatment 
period, and the metformin and doxycycline will be self-administered by the participants based on 
dose escalation timeline and study treatment follow-up phone calls. 
 

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Upon receipt of the of the study treatment supplies, an inventory must be performed and a drug 
receipt log filled out and signed by the person accepting the shipment. It is important that the 
designated study staff counts and verifies that the shipment contains all the items noted in the 
shipment inventory. Any damaged or unusable study drug in a given shipment (active drug or 
comparator) will be documented in the study files. The investigator must notify study sponsor of 
any damaged or unusable study treatments that were supplied to the investigator’s site.  
At the completion of the study, there will be a final reconciliation of drug shipped, drug 
consumed, and drug remaining. This reconciliation will be logged on the drug reconciliation 
form, signed and dated. Any discrepancies noted will be investigated, resolved, and 
documented prior to return or destruction of unused study drug. Drug destroyed on site will be 
documented in the study files.  
 
Subject Compliance Monitoring 
There will be two pill bottles with the appropriate number of metformin and doxycycline tablets 
distributed to the patients upon enrollment into the trial.  The pill bottles will be accompanied 
with a pill diary for each medication and detailed instructions on the proper dosage/number of 
tablets to take daily as noted above.  Upon arrival for definitive surgical resection, the diaries 
and bottles will be collected by our trial coordinator and the contents will be evaluated for 
compliance.  
 
Storage Requirements 
Drug will be stored in a locked cabinet until given to the participants at room temperature in the 
coordinated through the Thomas Jefferson University Hospital Investigational Drug Service 
(IDS) Pharmacy. Access to the locked cabinet will only be granted to the study coordinator.  The 
investigator must ensure that it is stored in accordance with the environmental conditions as 
defined in the Investigator Brochure. Clinical supplies may not be used for any purpose other 
than that stated in the protocol. 
 
Returns 
The investigator is responsible for keeping accurate records of the clinical supplies received 
from the Sponsor or designee, the amount dispensed to the subjects and the amount remaining 
at the conclusion of the trial. 
 
Upon completion or termination of the study, all unused and/or partially used investigational 
product will be destroyed at the site per institutional policy. It is the Investigator’s responsibility 
to arrange for disposal of all empty containers, provided that procedures for proper disposal 
have been established according to applicable federal, state, local and institutional guidelines 
and procedures, and provided that appropriate records of disposal are kept. 
 
5.2.5 Dose Limiting Toxicity Criteria 
Dose-limiting toxicities (DLTs) will be graded in severity according to the guidelines outlined in 
the NCI- CTCAE version 4.03.  Dose-limiting hematologic and non-hematologic toxicities will be 
defined differently, and will be based on events that occur during study drug administration and 
for 30 days after the completion of the therapy.  In order to be declared a dose-limiting toxicity, 
an adverse experience must be related (definitely, probably, or possibly) to study therapy.  
 
5.3 Surgical Resection 
Surgical Resection will occur immediately following the last scheduled dose of metformin and 
doxycycline.  Surgical technique to be used will be at the surgeon’s discretion.  Every effort 
should be made to have tumor tissue flash frozen as quickly as possible after resection. AEs 

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and concomitant medications will be evaluated and recorded prior to surgery.  Adverse events 
and concomitant medications considered by the Investigator to be related to surgical resection 
will be recorded in appropriate source documentation; however, such AEs and concomitant 
medications will not be recorded on CRFs.  
 
5.4 Concomitant Medications/Treatments 
Medications or vaccinations specifically prohibited in the exclusion criteria are not allowed 
during the ongoing trial. If the patient is on any of the Class C medications as outlined in Section 
5.4.2, they should be monitored closely for any potential interactions or side effects. If there is a 
clinical indication for one of these or other medications or vaccinations specifically prohibited 
during the trial, discontinuation from trial therapy or vaccination may be required. The 
investigator should discuss any questions regarding this with the Sponsor. The final decision on 
any supportive therapy or vaccination rests with the investigator and/or the subject's primary 
physician. However, the decision to continue the subject on trial therapy or vaccination schedule 
requires the mutual agreement of the Investigator, the Sponsor, and the subject.  
 
5.4.1 Acceptable Concomitant Medications 
All treatments that the investigator considers necessary for a subject’s welfare may be 
administered at the discretion of the investigator in keeping with the community standards of 
medical care. All concomitant medication and therapies will be recorded on the case report form 
(CRF) including all prescription, over-the-counter (OTC), herbal supplements, and IV 
medications and fluids. If changes occur during the trial period, documentation of drug dosage, 
frequency, route, and date should also be included on the CRF. These will be cross referenced 
against the list of drugs in section 4.2 (Exclusion Criteria) to ensure that no agents that are 
contraindicated with metformin or doxycycline are used.   
 
All concomitant medications received within 28 days before informed consent is signed and 30 
days after the last dose of trial treatment should be recorded. Concomitant medications 
administered to treat SAEs and ECIs should be recorded as defined in Section 8.2 
 
5.4.2 Prior and Concomitant Medication 
All medications are permitted except those that are contraindicated with metformin and 
doxycycline under current FDA recommendations.  It is important to note that the medications 
that are contraindicated with metformin are contraindicated due to concern for theoretical 
interactions. Class C medications are allowed if they are established at baseline. The treating 
physician should be made aware of any new Class C medications taken during therapy for 
proper monitoring of potential interactions. The following is a list of medications identified as 
class C (monitor therapy) and class D (consider therapy modification) when treatment with 
metformin or doxycycline is considered: 
 
Class C: 
 
 
 
 
 
Class D: 
Carbonic anhydrase inhibitors 
 
 
Bismuth Subsalicylate  
Cephalexin 
 
 
 
 
 
Cimetidine 
 
 
 
Corticosteroids (orally inhaled) 
 
 
Iodinated contrast agents 
Corticosteroids (systemic) 
 
 
 
Somatropin 
Dalfampridine 
Dofetilide 
Glycopyrrolate 
Lamotrigine 
Luteinizing hormone-releasing hormone analogs 

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Pegvisomant 
Penicillin 
Trospium 
 
 
5.5 Dietary Restrictions 
Subjects should maintain a normal diet unless modifications are required to manage an AE such 
as diarrhea, nausea or vomiting. Patients will be asked to fill a dietary log at the beginning the 
study when they speak with a registered dietician. 
 
6 Study Procedure 
All patients will be evaluated by a treating surgeon.  Initial visit will include overall assessment of 
health as well as determination of eligibility. A study calendar details the requisite pretreatment 
evaluations. 

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Study Procedure 
ScreeningA 
Treatment/Intervention Period D 
End of 
Treatment 
Visit E 
Long term 
Follow-up G 
Week 1 
Week 2-5 D 
Surgical 
ResectionF  
 
Day 1 -7 
Day 8+ 
 
 
 
 
Administrative 
Procedures 
  
Inclusion/Exclusion 
Criteria 
X 
  
  
  
  
  
  
  
  
  
Pregnancy Test 
XH 
 
 
 
 
 
 
 
 
 
Demographics, 
Medical history  
X 
  
  
  
  
  
  
  
  
  
Clinical 
Assessment 
  
  
  
  
Physical 
examinationI 
XJ 
  
  
  
  
  
  
  
x 
 
ECOG 
Performance status 
X 
  
  
  
  
  
  
  
 X 
 
Pathology Report 
histologic suspicion 
or confirmation of 
diseaseL 
X 
  
  
  
  
  
  
 X 
 
 
Concomitant medsK 
X 
 
X¥ 
X¥ 
 
 
X¥ 
X 
X 
X 
Toxicity and AE 
AssessmentK  
X 
 
 X¥ 
X¥  
  
  
 X¥ 
X  
x 
x 

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* Nutrition assessment will occur within seven days of enrollment when possible, and may be done via a phone interview. 
¥ Con Meds and AE/Toxicity Assessments should be performed only during day 3, day 5, and (if applicable) subsequent weekly follow-up phone calls. 
A. Written informed consent must be obtained before any study-specific screening assessments are performed. Lab results performed as standard-of-care prior to obtaining informed 
consent and within 28 days prior to enrollment may be used; such tests do not need to be repeated for screening. Trial treatment should begin within 5 days of eligibility confirmation.  
B. Blood Chemistry includes: Creatinine, AST, ALT, ALK Phos,T Bili > 2.5 x ULN. Hematology includes: CBC (with differential). Non-fasting labs. If labs were completed within 28 days 
prior to enrollment, these values can be used for eligibility/screening and labs need not be repeated. 
C. Study treatment follow-up phone calls will occur on days 3 ±2 days and 5 (± 2 days) of dose escalation to evaluate tolerability, document AEs, and concomitant medications. If patient 
remains on study drugs for >7 days, study treatment follow-up phone calls will occur a minimum of once a week until surgery to evaluate tolerability, AEs, and con meds. Last doses of 
Metformin and Doxycycline pills should not be taken up to 12 hours before scheduled surgery time. 
D. Patient must receive a minimum of 7 days of metformin and doxycycline before having definitive cancer surgery. Patients will stay on metformin and doxycycline until the day prior to 
surgery (up to the maximum of 5 weeks). 
E. End of treatment visit may occur within 21 days ±7 days of stopping study drug. 
F. Correlative study blood to be collected the morning of surgical resection.  
Laboratory testsB 
  
  
  
  
Hematology and 
Blood Chemistry 
X 
  
  
  
  
  
  
  
  
 
Treatment/ 
  
  
  
  
Intervention 
  
  
Metforminc 
  
X 
X 
X 
X 
X 
X 
  
  
  
Doxycyclinec 
  
X 
X 
X 
X 
X 
X 
  
  
  
Diagnostic Biopsy 
or tumor sampleO 
X 
 
 
 
 
 
 
 
 
 
Surgical Resection 
 
 
 
 
 
 
 
XN 
 
 
Correlative 
Studies 
  
  
  
  
Serologic 
metabolic 
profile (miR21 
and exosomes) 
 
X  
  
  
  
  
  
X 
  
  
Nutrition 
Assessment* 
 
XM 
 
 
 
 
 
 
 
 

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G. Follow up phone call will be performed 30 days (+ 5 days) after last dose of study medication for any other side effects or toxicity. Subject medical records will be reviewed every 3 
months (+ 1 month) for 12 months. 
H. Urine or blood pregnancy test must be done within 14 days prior to enrollment on study for all women of childbearing potential. 
I. Physical examinations should include vital signs, weight and blood pressure 
J. Screening physical examination should include height.  
K. Concomitant medication reconciliation, and Toxicity and Adverse Event assessments should be done at every patient contact to fully capture any potential dose limiting toxicities or 
AEs that affect the patient’s ability, willingness, and eligibility to continue taking study medications. 
L. Operative reports should be included with pathology reports in source documents when applicable. 
M. This optional assessment should be performed by a registered dietician. When applicable, the RD will meet with the patient within seven days of enrollment and record the patient’s last 
3 days of caloric intake and estimate their caloric intake versus their caloric needs per the Harris Benedict Equation. 
N. Tumor tissue should be flash frozen as quickly as possible after resection.   
O. Baseline tissue specimen will be obtained for comparative analysis when available.

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6.1 Screening Assessment  
Before initiating any screening activities, the scope of the study will be explained to each 
patient during informed consent. Patients should be advised of any known risks inherent in the 
planned procedures, any alternative treatment options, their right to withdraw from the study at 
any time for any reason, and their right to privacy. After this explanation, patients should be 
asked to sign and date a Notice of Privacy Practice research authorization/HIPAA form and an 
IRB-approved statement of informed consent that meets the requirements of the Code of 
Federal Regulations (Federal Register Vol. 46, No. 17, January 27, 1981, part 50). During the 
screening period, subject eligibility will be determined according to the inclusion and exclusion 
criteria (Section 4.1,4.2). The following assessments will be performed during this time:  
• 
Obtain informed consent and research authorization 
• 
Inclusion/Exclusion Criteria 
• 
Record demographics (including age) and medical history  
 
• 
Physical exam 
• 
Urine or Blood Pregnancy test (within 14 days for women of child bearing potential) 
• 
Discuss and record concomitant medications 
• 
ECOG performance status, vital signs [body temperature, blood pressure, pulse, 
respiratory rate, weight, height] 
• 
Obtain histologic or (if appropriate) radiologic confirmation of disease 
• 
Confirm eligibility according to the inclusion/exclusion criteria 
• 
Laboratory tests (within 28 days of enrollment): 
o Hematology (CBC with diff) 
o Blood Chemistry 
 
Creatinine, AST, AT, ALK Phos T Bili > 2.5 x ULN (all are 
SOC) 
• 
If possible, baseline caloric intake assessment using a dietary log mediated by a 
nutritionist.  This will take place at the patient’s baseline assessment if possible and 
may be done via a phone interview.   
o If caloric intake is completed, a calculation of the patient’s estimated 
caloric needs via the Harris-Benedict Equation will be performed. 
 
6.2 Treatment Period (Week 1 Day 1 – day prior to Surgical Resection) 
After screening is completed and eligibility is confirmed, Metformin and Doxycycline will be 
ordered by a study investigator and the medication will be dispensed by the Investigation Drug 
Service pharmacy. The date subjects begin taking metformin and doxycycline will be 
considered Week 1 Day 1, and a return to clinic is not necessary. Surgical resection will be 
scheduled a minimum of 7 days after the start of metformin and doxycycline and maximum of 5 
weeks. The participant will receive a Patient Medication Diary to record the time (AM and PM) 
and number of pills to take for both Metformin and Doxycycline.  
 
See Study Calendar (Section 6 above) for when the following assessments will be performed 
during the treatment period:  
• 
Study Treatment: 
o Metformin 
o Doxycycline 
• 
Study treatment follow-up phone calls (Day 3 +2 days and Day 5 +2 days from start 
of medication, and weekly thereafter until surgical resection)  
• 
Concomitant medications  

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• 
Adverse event assessment 
 
6.3 Surgical Resection 
The following study activities will occur on the day of surgical resection: 
• 
Two SST red-top tubes of blood for correlative studies: oncomiR miR-21, serum 
triglycerides, IGF-1, IGF-BP3, ESR, adiponectin, leptin, IGF-1R, exosome evaluation, 
metabolomics profile, and microRNA expression profile. 
• 
Definitive cancer surgery 
o Pathology report needed 
o Tumor tissue  
 
Exosome evaluation, metabolomics profile, and microRNA expression 
profile.  
• 
Return all Metformin and Doxycycline medication bottles (including any unused 
tablets/pills) 
• 
Collection of pill diaries 
6.4 End of Treatment Study Visit (Within 21 Days +7 of stopping protocol 
study medications) 
The following study activities will occur at End of Treatment Visit after patients have 
completed treatment with metformin and doxycycline: 
• 
Physical exam  
• 
Vital signs 
• 
ECOG performance status  
• 
Concomitant medications 
• 
Adverse event assessment 
 
6.5 Long term Follow-up 
A follow up phone call will be performed 30 days (+5 days) after the last dose of metformin and 
doxycycline for any other side effects or adverse events. This is allowed to coincide with the 
End of Treatment study visit if it occurs during timing overlap. Subjects will be followed for 12 
months following the End of Treatment visit or until death.  Subjects withdrawn from the study 
because of AEs will be followed until the adverse event has either resolved or stabilized. 
Reasons for premature withdrawal should be determined and noted.  
 
The participant’s medical records will be reviewed every 3 months (+1 month) for 12 months to 
assess overall survival and final pathologic staging. 
 
7 Study Procedures and Evaluations 
The Trial Flow Chart- Section 6 summarizes the trial procedures to be performed at each visit.  
Individual trial procedures are described in detail below.  It may be necessary to perform these 
procedures at unscheduled time points if deemed clinically necessary by the investigator. 
Tumor biopsies will be formalin fixed and paraffin embedded.  If a confirmatory diagnostic core 
biopsy is required and there is excess tissue available not needed in the course of clinical care, 
this tissue will be flash frozen in liquid nitrogen.  When a pre-treatment sample has been 
acquired in this manner, and if there is excess tissue is available at the time of resection, these 
tissue samples will also be frozen in liquid nitrogen as well. 
 

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When possible, a registered dietician will meet with the patients within the first seven days of 
enrollment and through an interview record their last 3 days of caloric intake per their 
recollection and record this on a specific case report form.  The dietician will also then use their 
height, weight, age, gender, and self-reported activity level per the Harris Benedict Equation to 
estimate their caloric intake versus their caloric needs.   
 
Serologic Analysis of the metabolic profile of the patients will be performed at the time of 
enrollment and the time of resection.  Two serum separator tubes of blood will be collected and 
transported at room temperature before being stored at -4 degrees C in a locked refrigerator. 
 
7.1 Administrative Procedures 
 
7.1.1 Informed Consent 
The Investigator must obtain documented consent from each potential subject prior to 
participating in a clinical trial. Consent must be documented by the subject’s dated signature on 
a consent form along with the dated signature of the person conducting the consent discussion.  
A copy of the signed and dated consent form should be given to the subject before participation in 
the trial. The initial informed consent form, any subsequent revised written informed consent 
form and any written information provided to the subject must receive the IRB/ERC’s 
approval/favorable opinion in advance of use. The subject should be informed in a timely 
manner if new information becomes available that may be relevant to the subject’s willingness to 
continue participation in the trial. The communication of this information will be provided and 
documented via a revised consent form or addendum to the original consent form that 
captures the subject’s dated signature. 
7.1.2 Inclusion/Exclusion Criteria 
All inclusion and exclusion criteria will be reviewed by the investigator or qualified designee to 
ensure that the subject qualifies for the trial. Eligibility will be confirmed prior to the patient 
starting study medication. 
 
7.1.3 Medical History 
A medical history will be obtained by the investigator or qualified designee. Medical history will 
include all active conditions, and any condition diagnosed within the prior 10 years that are 
considered to be clinically significant by the Investigator. Details regarding the disease for which 
the subject has enrolled in this study will be recorded separately and not listed as medical history. 
 
7.1.4 Prior and Concomitant Review 
Prior Medication 
The investigator or qualified designee will review prior medication use, including any protocol-
specified washout requirement, and record prior medication taken by the subject within 28 
days before starting the trial. Treatment for the disease for which the subject has enrolled in 
this study will be recorded separately and not listed as a prior medication. 
 
Concomitant Medications/Therapies 
The investigator or qualified designee will record medication, if any, taken by the subject 
during the trial. All medications related to reportable SAEs and ECIs should be recorded as 
defined in Section 7.2. 
 
7.1.5 Disease Details and Treatments  
Prior Cancer History 

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The investigator or qualified designee will obtain prior and current details regarding disease 
status. 
 
Prior Cancer Treatment 
The investigator or qualified designee will review all prior cancer treatments including systemic 
treatments, radiation and surgeries. 
 
Subsequent Anti-Cancer Therapy Status 
The investigator or qualified designee will review all new anti-neoplastic therapy initiated after 
the last dose of trial treatment. If a subject initiates a new anti-cancer therapy within 30 days 
after the last dose of trial treatment, the 30 day Safety Follow-up visit must occur before the first 
dose of the new therapy. Once new anti-cancer therapy has been initiated the subject will move 
into follow-up. 
 
7.2 Clinical Assessment 
7.2.1 Adverse Event (AE) Monitoring 
The investigator or qualified designee will assess each subject to evaluate for potential new or 
worsening AEs as specified in the Trial Flow Chart (Section 6) and more frequently if clinically 
indicated. Adverse experiences will be graded and recorded throughout the study and during the 
follow- up period according to NCI CTCAE Version 4.03 (see Section 8 . 3 ). Toxicities will 
be characterized in terms of seriousness, causality, toxicity grading, and action taken with 
regard to trial treatment. Please refer to Section 8.2 for detailed information regarding the 
assessment and recording of AEs. 
7.2.2 Physical Examination 
The investigator or qualified designee will perform a physical examination during the screening 
period. Clinically significant abnormal findings should be recorded as medical history. A 
physical examination will be performed at the end of therapy study visit as specified in the Trial 
Flow Chart (Section 6.0). 
 
7.2.3 Vital Signs 
The investigator or qualified designee will take vital signs at screening, and at the end of 
therapy study visit as specified in the Trial Flow Chart (Section 6.0).Vital signs should include 
temperature, pulse, respiratory rate, weight and blood pressure. Height will be measured at 
screening only. 
 
7.2.4 Eastern Cooperative Oncology Group (ECOG) Performance Scale 
The investigator or qualified designee will assess ECOG status at screening and at the end of 
therapy study visit as specified in the Trial Flow Chart (Section 6.0). 
 
7.3 Laboratory Safety Evaluations  
Laboratory tests for hematology, chemistry, and others are specified in Table 3. The total 
amount of blood to be drawn over the course of the trial (from pre-trial to post-trial visits), 
including approximate blood by visit and by sample type per subject can be found in the 
Procedures Manual. 
 
Table 3 
Laboratory Tests 
Hematology 
Chemistry 
Correlatives 
Hematocrit 
Creatinine 
miR21 
Hemoglobin 
Alkaline phosphatase 
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Platelet count 
Alanine aminotransferase (ALT) 
IGF-BP3 
WBC (total and differential) Aspartate aminotransferase (AST) ESR 
Red Blood Cell Count 
Total Bilirubin  
Adiponectin 
Absolute Neutrophil Count  
Leptin 
 
 
IGF-1R 
 
 
Exosome profile 
 
 
Metabolomics profile 
 
Screening laboratory tests should be performed within 28 days prior to enrollment. Results must 
be reviewed by the investigator or qualified designee and found to be acceptable prior to 
enrollment on this treatment trial. 
 
7.3.1 Correlative Studies  
Serum studies as described above will be drawn anytime during the screening period and/up to 
Week 1 Day 1 and at the time of surgical resection. 
 
8 Safety Evaluations 
8.1 
Specification of Safety Parameters 
8.1.1 
Unanticipated Problems 
Unanticipated problems (UAPs) include, in general, any incident, experience, or outcome that 
meets the following criteria: 
• 
unexpected in terms of nature, severity, or frequency given (a) the research procedures 
that are described in the protocol-related documents, such as the IRB-approved 
research protocol and informed consent document; and (b) the characteristics of the 
participant population being studied; 
UAPs are considered to pose risk to participants or others when they suggest that the research 
places participants or others at a greater risk of harm (including physical, psychological, 
economic, or social harm) than was previously known or recognized. 
8.1.2 Adverse Events 
An adverse event is any untoward or unfavorable medical occurrence in a human participant, 
including any abnormal sign (for example, abnormal physical exam or laboratory finding), 
symptom, or disease, temporally associated with the participant’s participation in the research, 
whether or not considered related to the participant’s participation in the research. 
 
 
 
8.1.5 Serious Adverse Event (SAE) 
A serious adverse event (SAE) is one that meets one or more of the following criteria: 
• 
Results in death 
• 
Is life-threatening (places the participant at immediate risk of death from the event as it 
occurred) 

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• 
Is disabling or incapacitating 
• 
Results in inpatient hospitalization or prolongation of existing hospitalization 
• 
Results in a persistent or significant disability or incapacity 
• 
Results in a congenital anomaly or birth defect  
• 
An important medical event that may not result in death, be life threatening, or require 
hospitalization may be considered an SAE when, based upon appropriate medical 
judgment, the event may jeopardize the participant or may require intervention to 
prevent one of the outcomes listed in this definition. 
 
 
8.2 Safety Assessment and Follow-Up 
The PI will follow adverse events with start dates occurring any time after study drug 
administration until 7 (for non-serious AEs) or 30 days (for SAEs) after the last day of study 
participation. At each study visit, the investigator (or designee) will inquire about the occurrence 
of AE/SAEs since the last visit. Events will be followed for outcome information until resolution 
or stabilization. 
 
 
8.3 Recording Adverse Events 
The following subsections detail what information must be documented for each adverse event 
occurring during the time period specified in Section Error! Reference source not found. 
Error! Reference source not found..  
8.3.1 
Relationship to Study Intervention 
The relationship to study intervention or study participation must be assessed and documented 
for all adverse events. Evaluation of relatedness must consider etiologies such as natural 
history of the underlying disease, concurrent illness, concomitant therapy, study-related 
procedures, accidents, and other external factors. 
  
The following guidelines are used to assess relationship of an event to study intervention: 
 
1. Related (Possible, Probable, Definite) 
a. The event is known to occur with the study intervention. 
b. There is a temporal relationship between the intervention and event onset. 
c. The event abates when the intervention is discontinued. 
d. The event reappears upon a re-challenge with the intervention. 
2. Not Related (Unlikely, Not Related) 
a. There is no temporal relationship between the intervention and event onset. 
b. An alternate etiology has been established. 
8.3.2 
Expectedness 
The PI is responsible for determining whether an AE is expected or unexpected. An AE will be 
considered unexpected if the nature, severity, or frequency of the event is not consistent with 
the risk information previously described for the intervention. Risk information to assess 
expectedness can be obtained from preclinical studies, the investigator’s brochure, published 
medical literature, the protocol, or the informed consent document. 
8.3.3 
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Adverse events will be graded for severity according to the Common Terminology Criteria for 
Adverse Events (CTCAE) version 4.03. Any adverse event that changes CTCAE grade over the 
course of a given episode will have each change of grade recorded on the adverse event 
case report forms/worksheets (Table 4). 
 

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Table 4 
Evaluating Adverse Events 
 
V4.03 CTCAE 
Grading 
Grade 1 
Mild; asymptomatic or mid symptoms; clinical or diagnostic observations only; intervention not indicated. 
Grade 2 
Moderate; minimal, local or noninvasive intervention indicated; limiting age-appropriate instrumental ADL. 
Grade 3 
Severe or medically significant but not immediately life-threatening; hospitalization or prolongation or hospitalization 
indicated; disabling; limiting self-care ADL. 
Grade 4 
Life threatening consequences; urgent intervention indicated. 
Grade 5 
Death related to AE 
Seriousness 
A serious adverse event is any adverse event occurring at any dose or during any use of metformin or doxycycline product that: 
†Results in death; or 
†Is life threatening; or places the subject, in the view of the investigator, at immediate risk of death from the event as it occurred (Note: This does 
not include an adverse event that, had it occurred in a more severe form, might have caused death.); or 
†Results in a persistent or significant disability/incapacity (substantial disruption of one’s ability to conduct normal life functions); or 
†Results in or prolongs an existing inpatient hospitalization (hospitalization is defined as an inpatient admission, regardless of length of stay, 
even if the hospitalization is a precautionary measure for continued observation. (Note: Hospitalization [including hospitalization for an elective 
procedure] for a preexisting condition which has not worsened does not constitute a serious adverse event.); or 
†Is a congenital anomaly/birth defect (in offspring of subject taking the product regardless of time to diagnosis);or 
Is a new cancer; (that is not a condition of the study) or 
Is an overdose (whether accidental or intentional). Any adverse event associated with an overdose is considered a serious adverse event. An 
overdose that is not associated with an adverse event is considered a non-serious event of clinical interest and must be reported within 24 hours. 
Other important medical events that may not result in death, not be life threatening, or not require hospitalization may be considered a serious 
adverse event when, based upon appropriate medical judgment, the event may jeopardize the subject and may require medical or surgical 
intervention to prevent one of the outcomes  listed previously (designated above by a †). 
Duration 
Record the start and stop dates of the adverse event. If less than 1 day, indicate the appropriate length of time and units 
Action taken 
Did the adverse event cause the metformin or doxycycline product to be discontinued? 
Exposure 
Is there evidence that the subject was exposed to the Merck product such as: reliable history, acceptable compliance 
assessment (pill count, diary, etc.), expected pharmacologic effect, or measurement of drug/metabolite in bodily specimen? 
Time Course 
Did the AE follow in a reasonable temporal sequence from administration of the metformin or doxycycline? 
Is the time of onset of the AE compatible with a drug-induced effect (applies to trials with investigational medicinal product)? 
Likely Cause 
Is the AE not reasonably explained by another etiology such as underlying disease, other drug(s)/vaccine(s), or other host or 
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8.3.4 
Intervention 
Any intervention implemented to treat the adverse event must be documented for all adverse 
events. 
8.4 
Safety Reporting  
8.4.1 
Reporting to IRB 
8.4.1.1 Unanticipated Problems 
All incidents or events that meet criteria for unanticipated problems (UAPs) as defined in 
Section 8.1.1 Unanticipated Problems require the creation and completion of an unanticipated 
problem report form (OHR-20).  
UAPs that pose risk to participants or others, and that are not AEs, will be submitted to the IRB 
on an OHR-20 form via the eazUP system within 5 working days of the investigator becoming 
aware of the event.  
UAPs that do not pose risk to participants or others will be submitted to the IRB at the next 
continuing review.  
8.4.1.2 Adverse Events  
Grade 1 AEs will be reported to the IRB at continuing review.  
Grade 2 AEs will be reported to the IRB at the time of continuing review.  
8.4.1.3 Serious Adverse Events  
SAEs will be reported to the IRB on OHR-10 forms via the electronic reporting system (eSAEy) 
according to the required time frames described below. 
Grade 3-4 AEs that are unexpected and deemed to be at least possibly related to the study will 
be reported to the IRB within 2 working days of knowledge of the event. 
Grade 3-4 AEs that are deemed unrelated to the study will be reported to the IRB within 5 
working days.  
Grade 5 AEs will be reported to the IRB within one working day of knowledge of the event. 
All SAEs will be submitted to the IRB at continuing review, including those that were reported 
previously. 
8.4.2 Reporting to SKCC DSMC 
All AEs and SAEs, safety and toxicity data, and any corrective actions will be submitted to the 
DSMC per the frequency described in the SKCC DSMP. The report to the SKCC DSMC will 
also include any unanticipated problems that in the opinion of the PI should be reported to the 
DSMC. 

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For expedited reporting requirements, see table below:                                            DSMC 
AE/SAE Reporting Requirements 
8.4.3 
Reporting of Pregnancy 
If the female partner of a male patient becomes pregnant during the course of the study, the 
treating physician must be notified immediately. All confirmed pregnancies must be immediately 
reported to the medical monitor. All pregnancies will be followed until resolution (i.e., voluntary 
or spontaneous termination or birth) and assessed for congenital anomalies and birth defects. 
 
8.5 Halting Rules 
This study will be monitored by the DSMC committee.  
 
Acute toxicity will be monitored using CTCAE version 4.03 criteria during therapy and up to 30-
days post completion of surgical resection.  If the lowest dose of metformin and doxycycline 
develop toxicity ≥4, the study may be terminated after discussion with PI and sponsor.  
 

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9 Study Oversight 
In addition to the PI’s responsibility for oversight, study oversight will be under the direction of 
the SKCC’s Data and Safety Monitoring Committee (DSMC). The SKCC DSMC operates in 
compliance with a Data and Safety Monitoring Plan (DSMP) that is approved by the NCI. 
 
10 Statistical Analysis Plan 
10.1 General considerations:  
All analyses will be performed separately by cohort. 
 
10.2 Analysis for primary outcomes.  
The primary objective of the study is to assess the impact of metformin and doxycycline on 
CAV1 expression by immunohistochemistry (IHC) in carcinoma cells.  All patients from whom 
samples are obtained both pre- and post-treatment will be included in the primary analyses.  
Within-patient change in IHC scores will be analyzed using the Wilcoxon signed-rank test.   
 
10.3 Analysis for secondary outcomes.   
Analysis of change TOMM20, MCT1, and MCT4 will be performed using the Wilcoxon signed-
rank test. Analysis of secondary clinical outcomes will be primarily descriptive. Distribution of 
progress-free survival and overall survival will be estimated using the Kaplan-Meier method.  
The objective response rate will be estimated along with an exact 95% binomial confidence 
interval.  
 
10.4 Sample size justification 
The sample in each cohort is based on having 80% power to detect an average increase in 
CAV1 staining of 20% using a one-sided Wilcoxon signed-rank test with alpha=0.05.  Based on 
pilot data in other cancers, we assume the standard deviation of change scores to be 32%.  A 
sample size of 19 per cohort is required under these assumptions.  Allowing for approximately 
15% of patients to have missing pre- and or post-treatment data, we will recruit 23 women per 
cohort.  Cohort 1 will consist of breast cancer patients and cohort 2 will include both uterine and 
cervical (gynecologic) cancers. 
 
10.5 Interim analysis and early stopping. 
There will be no interim analysis for efficacy or futility. 
 
10.6 Stopping rules for safety 
Incidence of DLTs will be monitored continuously with potential stopping after 10 patients have 
been enrolled based on the Bayesian method of Thall and Simon.  We are comparing our 
experimental treatment to a standard of no treatment and assume no DLTs under standard of 
care.  Both agents are extremely safe and DLTs should be exceedingly rare.  In 900 patients 
treated with metformin alone, the discontinuation rate was 0.6%.  In 31 patients treated with IV 
doxycycline, 4 SAEs were observed, but none were related to the study drug.  Thus, it is 
reasonable to assume a prior distribution for the DLT rate in the combination of Beta(0.04,1.96). 

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That is, we assume a 2% event rate for the combination with information equivalent to data from 
2 patients.  We will stop the study for safety if the posterior probability that the rate of DLTs in 
the combination treatment is 5% or greater is greater than 90%.  Stopping rules are outlined in 
the table below. 
Number of patients enrolled 
Stop if number of patients with Grade 3 or 
higher toxicities is ≥  
10 
2 
11-22 
3 
23-35 
4 
36 
5 
Thall C.P., Simon R. Practical Bayesian guidelines for phase IIB clinical trials. Biometrics. 
1994;50:337–349. 
11 Data Handling and Record Keeping 
The investigators are responsible for ensuring the accuracy, completeness, legibility, and 
timeliness of the data reported.  All source documents should be completed in a neat, legible 
manner to ensure accurate interpretation of data.  The investigators will maintain adequate case 
histories of study subjects, including accurate case report forms (CRFs), and source 
documentation. 
 
11.1 Confidentiality 
Information about study subjects will be kept confidential and managed according to the 
requirements of the Health Insurance Portability and Accountability Act of 1996 (HIPAA). Those 
regulations require a signed subject authorization informing the subject of the following: 
• 
What protected health information (PHI) will be collected from subjects in this study 
• 
Who will have access to that information and why 
• 
Who will use or disclose that information 
• 
The rights of a research subject to revoke their authorization for use of their PHI. 
 
In the event that a subject revokes authorization to collect or use PHI, the investigator, by 
regulation, retains the ability to use all information collected prior to the revocation of subject 
authorization. For subjects that have revoked authorization to collect or use PHI, attempts 
should be made to obtain permission to collect at least vital status (i.e. that the subject is alive) 
at the end of their scheduled study period.  
 
11.2 Source Documents 
Source data is all information, original records of clinical findings, observations, or other 
activities in a clinical trial necessary for the reconstruction and evaluation of the trial. Source 
data are contained in source documents. Examples of these original documents and data 
records include: hospital records, clinical and office charts, laboratory notes, memoranda, 
subjects’ diary or evaluation checklists, pharmacy dispensing records, recorded data from 
automated instruments, copies or transcriptions certified after verification as being accurate and 
complete, microfiches, photographic negatives, microfilm or magnetic media x-rays, subject files 
and records kept at the pharmacy, at the laboratories, and at medico-technical departments 
involved in the clinical trial. 
 
11.3 Case Report Forms 

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The study case report form (CRF) is the primary data collection instrument for the study. All data 
requested on the CRF will be recorded. All missing data must be explained. If a space on the 
CRF is left blank because the procedure was not done or the question was not asked, write 
“N/D”. If the item is not applicable to the individual case, write “N/A”. All entries should be 
printed legibly in black ink. If any entry error has been made, to correct such an error, draw a 
single straight line through the incorrect entry and enter the correct data above it. All such 
changes must be initialed and dated. DO NOT ERASE OR WHITE OUT ERRORS. For 
clarification of illegible or uncertain entries, print the clarification above the item, then initial and 
date it. 
 
11.4 Study Records Retention 
It is the investigator’s responsibility to retain study essential documents for at least 2 years after 
the last approval of a marketing application in their country and until there are no pending or 
contemplated marketing applications in their country or at least 2 years have elapsed since the 
formal discontinuation of clinical development of the investigational product. These documents 
should be retained for a longer period if required by an agreement with the sponsor. In such an 
instance, it is the responsibility of the sponsor to inform the investigator/institution as to when 
these documents no longer need to be retained. 
 
12  Clinical Site Monitoring and Auditing 
Clinical site monitoring and auditing is conducted to ensure that the rights of human participants 
are protected, that the study is implemented in accordance with the protocol and/or other 
operating procedures, and that the quality and integrity of study data and data collection 
methods are maintained. Monitoring and auditing for this study will be performed in accordance 
with the SKCC’s Data and Safety Monitoring Plan (DSMP) developed by the SKCC Data and 
Safety Monitoring Committee (DSMC). The DSMP specifies the frequency of monitoring, 
monitoring procedures, the level of clinical site monitoring activities (e.g., the percentage of 
participant data to be reviewed), and the distribution of monitoring reports. Some monitoring 
activities may be performed remotely, while others will take place at the study site(s). 
Appropriate staff will conduct monitoring activities and provide reports of the findings and 
associated action items in accordance with the details described in the SKCC DSMP. 
 
13 Ethical Considerations 
This study is to be conducted according to US and international standards of Good Clinical 
Practice (FDA Title 21 part 312 and International Conference on Harmonization guidelines), 
applicable government regulations and Institutional research policies and procedures. 
This protocol and any amendments will be submitted to a properly constituted independent 
Institutional Review Board (IRB), in agreement with local legal prescriptions, for formal approval 
of the study conduct. The decision of the IRB concerning the conduct of the study will be made 
in writing to the investigator before commencement of this study. 
 
All subjects for this study will be provided a consent form that is compliant with local and federal 
regulations, describing this study and providing sufficient information for subjects to make an 
informed decision about their participation in this study. See Attachment for a copy of the 
Subject Informed Consent Form. This consent form will be submitted with the protocol for review 
and approval by the IRB for the study. The formal consent of a subject, using the IRB- approved 

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consent form, must be obtained before that subject is submitted to any study procedure. This 
consent form must be signed by the subject or legally acceptable surrogate, and the 
investigator-designated research professional obtaining the consent. 
 
13.1 Good Clinical Practice 
The study will be conducted in accordance with the International Conference on Harmonisation 
(ICH) for Good Clinical Practice (GCP) and the appropriate regulatory requirement(s). The 
investigator will be thoroughly familiar with the appropriate use of the drug as described in the 
protocol and Investigator’s Brochure. Essential clinical documents will be maintained to 
demonstrate the validity of the study and the integrity of the data collected. Master files should 
be established at the beginning of the study, maintained for the duration of the study and 
retained according to the appropriate regulations. 
 
13.2 Ethical Considerations 
The study will be conducted in accordance with ethical principles founded in the Declaration of 
Helsinki. The IRB/IEC will review all appropriate study documentation in order to safeguard the 
rights, safety and well-being of the patients. The study will only be conducted at sites where 
IRB/IEC approval has been obtained. The protocol, Investigator’s Brochure, informed consent, 
advertisements (if applicable), written information given to the patients (including diary cards), 
safety updates, annual progress reports, and any revisions to these documents will be provided 
to the IRB/IEC by the investigator. 
 
13.3 Patient Information and Informed Consent 
Before obtaining consent, members of the study team will review the rationale for the treatment 
program with the patient. The discussion will review the alternatives available (including 
hormonal therapy, chemotherapy, or supportive care as appropriate), the potential benefits of 
this program, the risks and the probability of their occurrence, and the procedures to minimize 
these risks. Should an AE occur, the provisions available to ensure medical intervention will also 
be reviewed. Why the risks are reasonable in relation to the anticipated benefits, incentives, or 
costs that will or may be incurred as a result of participating in the study, as well as the efforts to 
maintain confidentiality, will also be discussed with the patient. 
 
Patients will be required to sign and date a statement of informed consent that meets the 
requirements of the Code of Federal Regulations (Federal Register Vol. 46, No. 17, January 27, 
1981, part 50) and the IRB. The medical record will include a statement that written informed 
consent was obtained (and document the date that it was obtained) before the patient is 
enrolled in the study. The original signed document will become part of the patient’s medical 
record. 
 
The consent form will include the following: 
• 
the nature and objectives, potential toxicities, and benefits of the intended 
study 
• 
the length of therapy and likely follow-up required 
• 
alternatives to the proposed therapy (including available standard and 
investigational therapies) 
• 
the name of the investigator(s) responsible for the protocol 
• 
the right of the patient to accept or refuse treatment and to withdraw from 
participation in this study 

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• 
informed consent documents and sections in the research 
authorization/HIPAA forms should include who will have access to the 
subjects data and medical records  
 
13.4 Protection of Privacy 
Patients will be informed of the extent to which their confidential health information generated 
from this study may be used for research purposes. After this discussion, they will be asked to 
sign a Notice of Privacy Practice research authorization/HIPAA form. The original signed 
documents will become part of the patient’s medical records, and each patient will receive a 
copy of the signed documents. The use and disclosure of protected health information will be 
limited to the individuals described in the research authorization form. The research 
authorization form must be completed by the principal investigator and approved by the IRB. 
 
13.5 Protocol Compliance 
 The investigator will conduct the study in compliance with the protocol given approval/favorable 
opinion by the IRB/IEC and the appropriate regulatory authority(ies). Changes to the protocol 
will require approval from TJUH at SKCC and written IRB/IEC approval/favorable opinion prior 
to implementation, except when the modification is needed to eliminate an immediate hazard(s) 
to patients. The IRB/IEC may provide, if applicable regulatory authority(ies) permit, expedited 
review and approval/favorable opinion for minor change(s) in ongoing studies that have the 
approval /favorable opinion of the IRB/IEC. The investigator will submit all protocol modifications 
to TJUH at SKCC and the regulatory authority(ies) in accordance with the governing 
regulations. 
 
Any departures from the protocol must be fully documented in the source documents. On- site 
Audits 
 
Regulatory authorities, the IEC/IRB and/or TJUH at SKCC clinical quality assurance group may 
request access to all source documents, data capture records, and other study documentation 
for on-site audit or inspection. Direct access to these documents must be guaranteed by the 
investigator, who must provide support at all times for these activities. 
 
13.6 Drug Accountability 
Accountability for the drug at all study sites is the responsibility of the principal investigator. The 
investigator will ensure that the drug is used only in accordance with this protocol. Drug 
accountability records indicating the drug’s delivery date to the site (if applicable), inventory at 
the site (if applicable), use by each patient, and disposal of the drug will be maintained by the 
clinical site. Accountability records will include dates, quantities, lot numbers, expiration dates (if 
applicable), and patient numbers. 
 
13.7 Terminating or Modifying the Study  
Adverse event and laboratory data from this trial will be assessed by the lead site or the 
sponsor’s medical monitor on an ongoing basis. SAEs will be reviewed as they are reported to 
the lead site/sponsor, and the medical monitor will make an assessment regarding the safety of 
continuing or modifying the study. This assessment will be shared with the investigators either in 
writing or as part of a teleconference. Should the assessment of either the lead site/sponsor or 
the principal investigator be that the study should be terminated, the study will be closed to 
further accrual. Patients who are receiving metformin and doxycycline will be assessed 
individually by the investigator to see if it is in the patients’ best interest to continue, which might 

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be the case for a patient that is responding to the intervention. Follow-up safety assessments 
will be performed for all patients who are terminated from the study prematurely. 
 
Written notification documenting the  reason  for  study termination will be provided to the 
investigator or by the terminating party. Circumstances that may warrant termination include, but 
are not limited to: 
• 
Determination of unexpected, significant, or unacceptable risk to patients 
• 
Failure to enter patients at an acceptable rate 
• 
Insufficient adherence to protocol requirements 
• 
Insufficient complete and/or evaluable data 
• 
Plans to modify, suspend or discontinue the development of the drug 
 
Should the study be closed prematurely, all study materials must be returned 
 
13.8  Record Retention 
The investigator will maintain all study records according to ICH-GCP and applicable regulatory 
requirement(s). 
 
14 Study Finances 
14.1 Funding Source 
This study is financed through a grant from the Prostate Cancer Foundation. 
 
14.2 Conflict of Interest 
Any investigator who has a conflict of interest with this study (patent ownership, royalties, or 
financial gain greater than the minimum allowable by their institution, etc.) must have the conflict 
reviewed by a properly constituted Conflict of Interest Committee with a Committee-sanctioned 
conflict management plan that has been reviewed and approved by the study sponsor prior to 
participation in this study.  All Jefferson University Investigators will follow the TJU Conflicts of 
Interest Policy for Employees (107.03). 
 
14.3 Compliance with Trial Registration and Results Posting Requirements 
Under the terms of the Food and Drug Administration Modernization Act (FDAMA) and the Food 
and Drug Administration Amendments Act (FDAAA), the Sponsor of the trial is solely 
responsible for determining whether the trial and its results are subject to the requirements for 
submission to the Clinical Trials Data Bank, http://www.clinicaltrials.gov. Information posted will 
allow subjects to identify potentially appropriate trials for their disease conditions and pursue 
participation by calling a central contact number for further information on appropriate trial 
locations and trial site contact information. 
 
15 Publication Plan 
The PI holds the primary responsibility for publication of the any results of the study. Neither the 
complete nor any part of the results of the study carried out under this protocol, nor any of the 
information provided by the sponsor for the purposes of performing the study, will be published 
or passed on to any third party without the consent of the study sponsor. Any investigator 
involved with this study is obligated to provide the sponsor with complete test results and all 
data derived from the study. 
 
Literature References 
 

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1. Pollak M. Overcoming Drug Development Bottlenecks With Repurposing: Repurposing 
biguanides to target energy metabolism for cancer treatment. Nat Med. 2014;20(6):591-
3. 
2. El-Mir MY, Nogueira V, Fontaine E, Averet N, Rigoulet M, Leverve X. Dimethylbiguanide 
inhibits cell respiration via an indirect effect targeted on the respiratory chain complex I. J 
Biol Chem. 2000;275(1):223-8. 
3. Owen MR, Doran E, Halestrap AP. Evidence that metformin exerts its anti-diabetic effects 
through inhibition of complex 1 of the mitochondrial respiratory chain. Biochem J. 
2000;348 Pt 3:607-14. 
4. Wheaton WW, Weinberg SE, Hamanaka RB, Soberanes S, Sullivan LB, Anso E, et al. 
Metformin inhibits mitochondrial complex I of cancer cells to reduce tumorigenesis. Elife. 
2014;3:e02242. 
5. Foretz M, Guigas B, Bertrand L, Pollak M, Viollet B. Metformin: from mechanisms of action 
to therapies. Cell Metab. 2014;20(6):953-66. 
6. Chang MY, Rhee YH, Yi SH, Lee SJ, Kim RK, Kim H, Park CH, Lee SH. Doxycycline 
enhances survival and self- renewal of human pluripotent stem cells. Stem Cell Reports. 
2014; 3(2): 353-64. 
 
7. Shackelford, D.B. and R.J. Shaw, The LKB1-AMPK pathway: metabolism and growth 
control in tumour suppression. Nat Rev Cancer, 2009. 9(8): p. 563-75. 
 
8. Viollet, B., et al., Cellular and molecular mechanisms of metformin: an overview. Clin Sci 
(Lond), 2013. 122(6): p. 253-70. 
 
9. Jara, J.A. and R. Lopez-Munoz, Metformin and cancer: Between the bioenergetic 
disturbances and the antifolate activity. Pharmacol Res, 2015. 
10. Ben Sahra, I., et al., Targeting cancer cell metabolism: the combination of metformin and 
2-deoxyglucose induces p53-dependent apoptosis in prostate cancer cells. Cancer Res, 
2010. 70(6): p. 2465-75. 
11. Lord SR, Patel N, Liu D, Fenwick J, Gleeson F, Buffa F, et al. Neoadjuvant Window 
Studies of Metformin and Biomarker Development for Drugs Targeting Cancer 
Metabolism. J Natl Cancer Inst Monogr. 2015;2015(51):81-6. 
 
12. Salani B, Del Rio A, Marini C, Sambuceti G, Cordera R, Maggi D. Metformin, cancer and 
glucose metabolism. Endocr Relat Cancer. 2014;21(6):R461-71. 
 
13. Leone A, Di Gennaro E, Bruzzese F, Avallone A, Budillon A. New perspective for an old 
antidiabetic drug: metformin as anticancer agent. Cancer Treat Res. 2014;159:355-76. 
14. Sikka A, Kaur M, Agarwal C, Deep G, Agarwal R. Metformin suppresses growth of human 
head and neck squamous cell carcinoma via global inhibition of protein translation. Cell 
Cycle. 2012;11(7):1374-82. 
 

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Version 4.2 
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15 Nov 2018 
 
 
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page 55 of 59 
15. Skinner HD, Sandulache VC, Ow TJ, Meyn RE, Yordy JS, Beadle BM, et al. TP53 
disruptive mutations lead to head and neck cancer treatment failure through inhibition of 
radiation-induced senescence. Clin Cancer Res. 2012;18(1):290-300. 
16. Vitale-Cross L, Molinolo AA, Martin D, Younis RH, Maruyama T, Patel V, et al. Metformin 
prevents the development of oral squamous cell carcinomas from carcinogen-induced 
premalignant lesions. Cancer Prev Res (Phila). 2012;5(4):562-73. 
17. Leone A, Di Gennaro E, Bruzzese F, Avallone A, Budillon A. New perspective for an old 
antidiabetic drug: metformin as anticancer agent. Cancer Treat Res. 2014;159:355-76. 
18. Pollak M. Overcoming Drug Development Bottlenecks With Repurposing: Repurposing 
biguanides to target energy metabolism for cancer treatment. Nat Med. 2014;20(6):591-
3. 
19. Wheaton WW, Weinberg SE, Hamanaka RB, Soberanes S, Sullivan LB, Anso E, et al. 
Metformin inhibits mitochondrial complex I of cancer cells to reduce tumorigenesis. Elife. 
2014;3:e02242. 
20. Pollak M. Potential applications for biguanides in oncology. J Clin Invest. 
2013;123(9):3693-700. 
21. Marchiq I, Pouyssegur J. Hypoxia, cancer metabolism and the therapeutic benefit of 
targeting lactate/H symporters. J Mol Med (Berl). 2015. 
22. Pollak M. Overcoming Drug Development Bottlenecks With Repurposing: Repurposing 
biguanides to target energy metabolism for cancer treatment. Nat Med. 2014;20(6):591-
3. 
23. Lord SR, Patel N, Liu D, Fenwick J, Gleeson F, Buffa F, et al. Neoadjuvant Window 
Studies of Metformin and Biomarker Development for Drugs Targeting Cancer 
Metabolism. J Natl Cancer Inst Monogr. 2015;2015(51):81-6. 
24. Salani B, Del Rio A, Marini C, Sambuceti G, Cordera R, Maggi D. Metformin, cancer and 
glucose metabolism. Endocr Relat Cancer. 2014;21(6):R461-71. 
25. Wheaton WW, Weinberg SE, Hamanaka RB, Soberanes S, Sullivan LB, Anso E, et al. 
Metformin inhibits mitochondrial complex I of cancer cells to reduce tumorigenesis. Elife. 
2014;3:e02242. 
26. Sapadin AN, Fleischmajer R. Tetracyclines: nonantibiotic properties and their clinical 
implications. J Am Acad Dermatol. 2006; 54(2): 258-65. 
27. Saikali Z1, Singh G. Doxycycline and other tetracyclines in the treatment of bone 
metastasis. Anticancer Drugs. 2003; 14(10): 773-8. 
28. Duivenvoorden WC, Popović SV, Lhoták S, Seidlitz E, Hirte HW, Tozer RG, Singh G. 
Doxycycline decreases tumor burden in a bone metastasis model of human breast cancer. 
Cancer Res. 2002; 62(6): 1588-91. 
29. Javeshghani S, Zakikhani M, Austin S, Bazile M, Blouin MJ, Topisirovic I, et al. Carbon 
source and myc expression influence the antiproliferative actions of metformin. Cancer 
Res. 2012;72(23):6257-67. 
30. Birsoy K, Possemato R, Lorbeer FK, Bayraktar EC, Thiru P, Yucel B, et al. Metabolic 
determinants of cancer cell sensitivity to glucose limitation and biguanides. Nature. 
2014;508(7494):108-12. 

Metformin + Doxycycline in Breast, Uterine, and Cervical Cancer  
Version 4.2 
Protocol 16D.317 
 
15 Nov 2018 
 
 
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page 56 of 59 
31. Jensen DH, Therkildsen MH, Dabelsteen E. A reverse Warburg metabolism in oral 
squamous cell carcinoma is not dependent upon myofibroblasts. J Oral Pathol Med. 
2015;44(9):714-21. 
32. Luo, Q., et al., In vitro and in vivo anti-tumor effect of metformin as a novel therapeutic 
agent in human oral squamous cell carcinoma. BMC Cancer, 2012. 12: p. 517. 
33. Vitale-Cross, L., et al., Metformin prevents the development of oral squamous cell 
carcinomas from carcinogen-induced premalignant lesions. Cancer Prev Res (Phila), 
2012. 5(4): p. 562-73. 
34. Andrzejewski S, Gravel SP, Pollak M, St-Pierre J. Metformin directly acts on mitochondria 
to alter cellular bioenergetics. Cancer Metab. 2014;2:12. 
35. Madiraju AK, Erion DM, Rahimi Y, Zhang XM, Braddock DT, Albright RA, et al. Metformin 
suppresses 
gluconeogenesis 
by 
inhibiting 
mitochondrial 
glycerophosphate 
dehydrogenase. Nature. 2014;510(7506):542-6. 
36. Yen, Y.C., et al., Effect of metformin on the incidence of head and neck cancer in diabetics. 
Head Neck, 2015. 37(9): p. 1268-73. 
37. Vitale-Cross, L., et al., Metformin prevents the development of oral squamous cell 
carcinomas from carcinogen-induced premalignant lesions. Cancer Prev Res (Phila), 
2012. 5(4): p. 562-73. 
38. Becker, C., et al., Metformin and the risk of head and neck cancer: a case-control analysis. 
Diabetes Obes Metab, 2014. 16(11): p. 1148-54. 
39. El-Mir, M.Y., et al., Dimethylbiguanide inhibits cell respiration via an indirect effect targeted 
on the respiratory chain complex I. J Biol Chem, 2000. 275(1): p. 223-8. 
40. Becker, C., et al., Metformin and the risk of head and neck cancer: a case-control analysis. 
Diabetes Obes Metab, 2014. 16(11): p. 1148-54. 
41. El-Mir, M.Y., et al., Dimethylbiguanide inhibits cell respiration via an indirect effect targeted 
on the respiratory chain complex I. J Biol Chem, 2000. 275(1): p. 223-8. 
42. Owen, M.R., E. Doran, and A.P. Halestrap, Evidence that metformin exerts its anti-diabetic 
effects through inhibition of complex 1 of the mitochondrial respiratory chain. Biochem J, 
2000. 348 Pt 3: p. 607-14. 
43. Sagan, L. On the origin of mitosing cells. J Theor Biol 14, 255-274 (1967). 
44. Greber, B. J. et al. Ribosome. The complete structure of the 55S mammalian 
mitochondrial ribosome. Science 348, 303-308 (2015). 
45. Beckmann, R. & Herrmann, J. M. Structural biology. Mitoribosome oddities. Science 348, 
288-289 (2015). 
46. Amunts, A., Brown, A., Toots, J., Scheres, S. H. & Ramakrishnan, V. Ribosome. The 
structure of the human mitochondrial ribosome. Science 348, 95-98 (2015). 
47. Lamb, R. et al. Antibiotics that target mitochondria effectively eradicate cancer stem cells, 
across multiple tumor types: treating in vitroin vivocancer like an infectious disease. 
Oncotarget 6, 4569-4584, doi:3174 [pii] (2015). 
48. Martinez-Outschoorn UE, Lisanti MP, Sotgia F. Catabolic cancer-associated fibroblasts 
transfer energy and biomass to anabolic cancer cells, fueling tumor growth. Semin Cancer 
Biol. 2014;25:47-60. 
49. Romero IL, Mukherjee A, Kenny HA, Litchfield LM, Lengyel E. Molecular pathways: 
trafficking of metabolic resources in the tumor microenvironment. Clin Cancer Res. 
2015;21(4):680-6. 
50. DeNicola GM, Cantley LC. Cancer's Fuel Choice: New Flavors for a Picky Eater. Mol Cell. 
2015;60(4):514-23. 

Metformin + Doxycycline in Breast, Uterine, and Cervical Cancer  
Version 4.2 
Protocol 16D.317 
 
15 Nov 2018 
 
 
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page 57 of 59 
51. Schulze A, Harris AL. How cancer metabolism is tuned for proliferation and vulnerable to 
disruption. Nature. 2012;491(7424):364-73. 
52. Martinez-Outschoorn UE, Sotgia F, Lisanti MP. Power surge: supporting cells "fuel" 
cancer cell mitochondria. Cell Metab. 2012;15(1):4-5. 
53. Wallace DC. Mitochondria and cancer. Nat Rev Cancer. 2012;12(10):685-98. 
54. Marchiq I, Pouyssegur J. Hypoxia, cancer metabolism and the therapeutic benefit of 
targeting lactate/H symporters. J Mol Med (Berl). 2015. 
55. Pavlides S, Whitaker-Menezes D, Castello-Cros R, Flomenberg N, Witkiewicz AK, Frank 
PG, et al. The reverse Warburg effect: aerobic glycolysis in cancer associated fibroblasts 
and the tumor stroma. Cell Cycle. 2009;8(23):3984-4001. 
56. Martinez-Outschoorn UE, Sotgia F, Lisanti MP. Caveolae and signalling in cancer. Nat 
Rev Cancer. 2015;15(4):225-37. 
57. Sotgia F, Martinez-Outschoorn UE, Howell A, Pestell RG, Pavlides S, Lisanti MP. 
Caveolin-1 and cancer metabolism in the tumor microenvironment: markers, models, and 
mechanisms. Annu Rev Pathol. 2012;7:423-67. 
58. Martinez-Outschoorn UE, Lin Z, Whitaker-Menezes D, Howell A, Lisanti MP, Sotgia F. 
Ketone bodies and two-compartment tumor metabolism: stromal ketone production fuels 
mitochondrial biogenesis in epithelial cancer cells. Cell Cycle. 2012;11(21):3956-63. 
59. Sloan EK, Ciocca DR, Pouliot N, Natoli A, Restall C, Henderson MA, et al. Stromal cell 
expression of caveolin-1 predicts outcome in breast cancer. Am J Pathol. 
2009;174(6):2035-43. 
60. Witkiewicz AK, Dasgupta A, Sotgia F, Mercier I, Pestell RG, Sabel M, et al. An absence 
of stromal caveolin-1 expression predicts early tumor recurrence and poor clinical 
outcome in human breast cancers. Am J Pathol. 2009;174(6):2023-34. 
61. Jia Y, Wang N, Wang J, Tian H, Ma W, Wang K, et al. Down-regulation of stromal caveolin-
1 expression in esophageal squamous cell carcinoma: a potent predictor of lymph node 
metastases, early tumor recurrence, and poor prognosis. Ann Surg Oncol. 
2014;21(1):329-36. 
62. He Y, Zhao X, Gao J, Fan L, Yang G, Cho WC, et al. Quantum dots-based 
immunofluorescent imaging of stromal fibroblasts Caveolin-1 and light chain 3B 
expression and identification of their clinical significance in human gastric cancer. Int J 
Mol Sci. 2012;13(11):13764-80. 
63. Zhao Z, Han FH, Yang SB, Hua LX, Wu JH, Zhan WH. Loss of stromal caveolin-1 
expression in colorectal cancer predicts poor survival. World J Gastroenterol. 
2015;21(4):1140-7. 
64. Shan T, Lu H, Ji H, Li Y, Guo J, Chen X, et al. Loss of stromal caveolin-1 expression: a 
novel tumor microenvironment biomarker that can predict poor clinical outcomes for 
pancreatic cancer. PLoS One. 2014;9(6):e97239. 
65. Ayala G, Morello M, Frolov A, You S, Li R, Rosati F, et al. Loss of caveolin-1 in prostate 
cancer stroma correlates with reduced relapse-free survival and is functionally relevant to 
tumour progression. J Pathol. 2013;231(1):77-87. 

Metformin + Doxycycline in Breast, Uterine, and Cervical Cancer  
Version 4.2 
Protocol 16D.317 
 
15 Nov 2018 
 
 
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page 58 of 59 
66. Bertino EM, Williams TM, Nana-Sinkam SP, Shilo K, Chatterjee M, Mo X, et al. Stromal 
Caveolin-1 Is Associated With Response and Survival in a Phase II Trial of nab-Paclitaxel 
With Carboplatin for Advanced NSCLC Patients. Clin Lung Cancer. 2015;16(6):466-74 e4. 
67. Wu KN, Queenan M, Brody JR, Potoczek M, Sotgia F, Lisanti MP, et al. Loss of stromal 
caveolin-1 expression in malignant melanoma metastases predicts poor survival. Cell 
Cycle. 2011;10(24):4250-5. 
68. Foretz M, Guigas B, Bertrand L, Pollak M, Viollet B. Metformin: from mechanisms of action 
to therapies. Cell Metab. 2014;20(6):953-66. 
69. Anthonisen, N. R., Manfreda, J., Warren, C. P. W., Hershfield, E. S., Harding, G. K. M., & 
Nelson, N. A. (1987). Antibiotic therapy in exacerbations of chronic obstructive pulmonary 
disease. Annals of internal medicine, 106(2), 196-204. 
70. Lamb, P. J. (1978). Case studies of tropical Atlantic surface circulation patterns during 
recent sub-Saharan weather anomalies: 1967 and 1968. Monthly Weather Review, 
106(4), 482-491. 
71. Kooijman, S., van den Berg, R., Ramkisoensing, A., Boon, M. R., Kuipers, E. N., Loef, M., 
... & Houtkooper, R. H. (2015). Prolonged daily light exposure increases body fat mass 
through attenuation of brown adipose tissue activity. Proceedings of the National Academy 
of Sciences, 112(21), 6748-6753. 
72. Gemignani, F., Moreno, V., Landi, S., Moullan, N., Chabrier, A., Gutiérrez-Enríquez, S., ... 
& Canzian, F. (2004). A TP53 polymorphism is associated with increased risk of colorectal 
cancer and with reduced levels of TP53 mRNA. Oncogene, 23(10), 1954-1956. 
73. Tang, C., H. Paek, and M. Strome. Metformin Prevents the Progression of Carcinoma in 
Condemned Oral Mucosa in American Head and Neck Society Annual Meeting. 2015. 
Boston, MA. 
74. Chang MY, Rhee YH, Yi SH, Lee SJ, Kim RK, Kim H, Park CH, Lee SH. Doxycycline 
enhances survival and self- renewal of human pluripotent stem cells. Stem Cell Reports. 
2014; 3(2): 353-64. 
75. Houtkooper RH, Mouchiroud L, Ryu D, Moullan N, Katsyuba E, Knott G, Williams RW, 
Auwerx J. Mitonuclear protein imbalance as a conserved longevity mechanism. Nature. 
2013; 497(7450): 451-7. 
76. Cancer Facts and Figures 2015, A.C. Society, Editor. 2015: Atlanta 
77. Lee, J.J., et al., Predicting cancer development in oral leukoplakia: ten years of 
translational research. Clin Cancer Res, 2000. 6(5): p. 1702-10. 
78. Yardimci, G., et al., Precancerous lesions of oral mucosa. World J Clin Cases, 2014. 2(12): 
p. 866-72. 
79. Mehanna, H.M., et al., Treatment and follow-up of oral dysplasia - a systematic review 
and meta-analysis. Head Neck, 2009. 31(12): p. 1600-9. 
80. Shirani, S., et al., Epithelial dysplasia in oral cavity. Iran J Med Sci, 2014. 39(5): p. 406-
17. 
81. Caldeira, P.C., M.H. Abreu, and M.A. do Carmo, Binary system of grading oral epithelial 
dysplasia: evidence of a bearing to the scores of an immunohistochemical study. J Oral 
Pathol Med, 2012. 41(6): p. 452-3. 
82. Warnakulasuriya, S. and A. Ariyawardana, Malignant transformation of oral leukoplakia: a 
systematic review of observational studies. J Oral Pathol Med, 2015. 
83. Diajil, A., et al., Clinical outcome following oral potentially malignant disorder treatment: a 
100 patient cohort study. Int J Dent, 2013. 2013: p. 809248. 

Metformin + Doxycycline in Breast, Uterine, and Cervical Cancer  
Version 4.2 
Protocol 16D.317 
 
15 Nov 2018 
 
 
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page 59 of 59 
84. Kuribayashi, Y., et al., Recurrence patterns of oral leukoplakia after curative surgical 
resection: important factors that predict the risk of recurrence and malignancy. J Oral 
Pathol Med, 2012. 41(9): p. 682-8. 
85. Owen MR, Doran E, Halestrap AP. Evidence that metformin exerts its anti-diabetic effects 
through inhibition of complex 1 of the mitochondrial respiratory chain. Biochem J. 
2000;348 Pt 3:607-14. 
86. Wheaton WW, Weinberg SE, Hamanaka RB, Soberanes S, Sullivan LB, Anso E, et al. 
Metformin inhibits mitochondrial complex I of cancer cells to reduce tumorigenesis. Elife. 
2014;3:e02242. 
87. Rizos, C.V. and M.S. Elisaf, Metformin and cancer. Eur J Pharmacol, 2013. 705(1-3): p. 
96-108. 
88. Skinner HD, McCurdy MR, Echeverria AE, Lin SH, Welsh JW, O'Reilly MS, et al. 
Metformin use and improved response to therapy in esophageal adenocarcinoma. Acta 
Oncol. 2013;52(5):1002-9. 
89. Xiao X et al., Metformin impairs the growth of Liver Kinase B1-intact cervical cancer cells. 
Gynecol Oncol. 2012:127(1):249-255.