Clinical trial NCT02908490
Conditions: Arthritis, Rheumatoid Atherosclerosis
Keywords: Arthritis, Rheumatoid Atherosclerosis
Sponsor: Kimberly Liang
Start date: 2017-04-01; Completion date: 2020-12-31
Enrollment: 25 participants; Allocation: RANDOMIZED; Intervention model: CROSSOVER

Brief summary:
The purpose of this study is to determine whether sildenafil improves parameters of vascular function and blood markers involved in development of heart disease in patients with rheumatoid arthritis.

Detailed description:
Rheumatoid arthritis (RA) is associated with a 2-fold increased risk of cardiovascular disease (CVD), which is not explained by traditional cardiovascular (CV) risk factors alone; this risk is likely mediated in part through systemic inflammation. Indeed, RA itself is deemed to impart a CV risk equivalent to diabetes mellitus (DM). However, unlike in DM, optimal CV management strategies in RA are lacking. Despite improved anti-inflammatory therapies for RA, the mortality gap in RA compared to the general population is still widening, in part due to suboptimal primary and secondary CV preventive care in RA. To date, there have been no published controlled intervention trials for primary CV prevention in RA, despite this clearly urgent unmet need.

One of the early stages of atherogenesis is endothelial dysfunction, and drugs that target improvement in this are promising novel strategies for CVD prevention. The fundamental feature of endothelial dysfunction is impaired nitric oxide (NO) bioavailability. Sildenafil improves endothelial function by increasing NO signaling by inhibition of phosphodiesterase-5 (PDE5). PDE5 inhibitors improve endothelial function in pulmonary hypertension and DM, and were safe and well tolerated in patients with erectile dysfunction and other CV comorbidities. Furthermore, PDE inhibitors have immunomodulatory properties that may be utilized to treat autoimmune conditions like RA. The investigators' central hypothesis is that sildenafil is a uniquely suited agent targeting endothelial dysfunction as a novel adjunctive CV prevention strategy and immunomodulatory agent in RA. Specifically, their goal is to determine if sildenafil use in RA improves endothelial dysfunction and atherosclerosis biomarkers.

The proposed study is a phase II, randomized double-blind placebo-controlled crossover efficacy trial of 60 RA patients, with no known history of CVD but at least one traditional CV risk factor, on stable baseline doses of RA medications; randomized 1:1 to receive either sildenafil 50 mg or placebo orally once daily for 3 months, with a 2-week washout before the crossover phase for another 3 months. Vascular studies validated in assessing endothelial dysfunction and laboratory studies for selected atherosclerosis biomarkers will be performed at baseline, 3 months pre- and post-washout, and 6 months. Adverse events will be collected to assess safety. The Specific Aims are:

1. To determine whether sildenafil use in RA leads to improvement in parameters of vascular function; and to confirm its safety profile.
2. To determine whether sildenafil use in RA is associated with improvement in atherosclerosis biomarkers.

The results of this study will serve as preliminary data for future larger trials evaluating sildenafil as a CV prevention strategy by reducing endothelial dysfunction in RA. It will provide needed data on potential benefits of sildenafil for immunomodulation and CV prevention in this high-risk population.

Arms: arm 1: Sildenafil 50 mg orally once daily for first 3 months, then after 2-week washout, Placebo orally once daily for 3 months arm 2: Placebo orally once daily for first 3 months, then after 2-week washout, Sildenafil 50 mg orally once daily for 3 months
Interventions: intervention 1: Sildenafil intervention 2: Placebo
Intervention descriptions: intervention 1: Sildenafil 50 mg once daily intervention 2: Placebo once daily with same size, shape, color, and texture as Sildenafil 50 mg pill

Protocol documents:
Prot_SAP_000.pdf: 
 
PI: Liang, KP                                                      Study Protocol v7 07/10/19 
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Does Sildenafil Improve Endothelial Dysfunction in Rheumatoid Arthritis? 
Short Title: SEDRA Study 
 
NCT number  
 
 
NCT02908490 
Test drug 
 
 
 
Sildenafil  
Study purpose  
 
 
Efficacy and Safety 
Clinical study phase  
 
Phase II 
Funding agency 
 
 
University of Pittsburgh 
 
 
 
 
 
National Institutes of Health / NIAMS 
 
 
 
 
 
Study Drug provided by Pfizer, Inc. 
 
Principal investigator  
 
Kimberly P. Liang, MD, MS 
                          
 
 
Assistant Professor of Medicine 
  
 
 
 
Division of Rheumatology and Clinical Immunology 
                                                
University of Pittsburgh Medical Center 
                                              
3708 Fifth Ave., Ste. #501 
                                                
Pittsburgh, PA 15213 
 
 
 
 
 
Tel: (412) 383-8846 
                                                Fax: (412) 586-3540 
Co-PI:                                      
Larry W. Moreland, MD 
                                                
Margaret J. Miller Endowed Professor of Arthritis Research 
Professor of Medicine, Immunology, and Clinical and 
Translational Science 
Chief, Division of Rheumatology and Clinical Immunology 
S711 Thomas E. Starzl Biomedical Science Tower 
3500 Terrace Street 
Pittsburgh, PA 15261 
Phone: 412-648-0148 
Fax: 412-648-8894 
E-mail: lwm5@pitt.edu 
 


 
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Signature Page 1 
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 U.S. federal regulations and ICH guidelines. 
The Lead Principal Investigator (Protocol Chair) should sign Signature Page 1.  A copy of this 
Signature Page 1 should be filed with the holder of the Regulatory documents and a copy should be 
maintained at the site. 
PRINCIPAL INVESTIGATOR 
 
KIMBERLY P. LIANG, MD 
PRINTED NAME 
 
______________________________________________________     __________________________ 
SIGNATURE 
 
 
 
 
 
 
 
 
DATE 
 
CO-INVESTIGATOR/S: 
 
______________________________________________________ 
PRINTED NAME 
 
______________________________________________________    ___________________________ 
SIGNATURE 
 
 
 
 
 
 
 
 
DATE 
 
 


 
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Contents 
Signature Page 1 ......................................................................................................................................... 2 
1. 
PROTOCOL SYNOPSIS ................................................................................................................ 9 
2. 
INTRODUCTION ..................................................................................................................... 1415 
 
Background ......................................................................................................................... 1415 
2.1.1 
CARDIOVASCULAR RISK AND ENDOTHELIAL DYSFUNCTION IN RA ...... 1415 
2.1.2 
SILDENAFIL .............................................................................................................. 1617 
3. 
Study Drug ................................................................................................................................. 1718 
 
Mechanism of Action ......................................................................................................... 1718 
 
Rationale ............................................................................................................................. 1718 
4. 
Risk-Benefit assessment ............................................................................................................ 1920 
 
Benefits of Study in General: ............................................................................................. 1920 
 
Potential Risks of Study in General: ................................................................................... 1920 
5. 
STUDY OBJECTIVES .............................................................................................................. 2021 
 
Primary endpoint ................................................................................................................ 2021 
 
The Primary Efficacy Outcome measures will be: ............................................................. 2021 
5.2.1 
Brachial Artery Flow Mediated Dilation (FMD) Without Nitroglycerin ................... 2021 
5.2.2 
Peripheral Arterial Tone (PAT)................................................................................... 2122 
5.2.3 
Safety Profile: Adverse Event Outcomes: ................................................................... 2122 
 
Secondary endpoint ............................................................................................................ 2122 


 
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6. 
INVESTIGATORY TEAM ....................................................................................................... 2223 
7. 
STUDY DESIGN....................................................................................................................... 2425 
 
Overview ............................................................................................................................ 2425 
 
Phase one ............................................................................................................................ 2425 
7.2.1 
Screening phase (up to 4 weeks) ................................................................................. 2425 
 
Phase two ............................................................................................................................ 2425 
7.3.1 
Initial Study Treatment phase (Month 0 to Month 3) ................................................. 2425 
 
Phase three .......................................................................................................................... 2526 
7.4.1 
Washout phase (Month 3 to 2 weeks-post Month 3) .................................................. 2526 
7.4.2 
Crossover Treatment phase (Month 3 post 2-week-washout to Month 6) .................. 2526 
7.4.3 
Termination Visit and Safety Follow-up Visit ............................................................ 2526 
8. 
STUDY POPULATION ............................................................................................................ 2627 
 
Inclusion criteria ................................................................................................................. 2627 
 
Exclusion criteria ................................................................................................................ 2728 
 
Justification of selection criteria ......................................................................................... 2829 
 
Withdrawal of Subjects .......................................................................................................... 29 
 
Replacement of Withdrawn Subjects ..................................................................................... 30 
 
Subject Identification .............................................................................................................. 30 
 
Study Population Demographics ........................................................................................ 3031 
9. 
TREATMENT ............................................................................................................................... 31 


 
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Study drug............................................................................................................................... 31 
9.1.1 
Sildenafil ..................................................................................................................... 3132 
9.1.2 
Matching placebo ........................................................................................................ 3132 
 
Justification of study drug selection ................................................................................... 3132 
 
Assignment – Randomization ................................................................................................. 32 
 
Blinding .................................................................................................................................. 32 
9.4.1 
Allocation Concealment and Blinding ........................................................................ 3233 
9.4.2 
Emergency Unblinding ............................................................................................... 3233 
 
Drug logistics and Accountability .......................................................................................... 33 
Drug logistics and accountability .......................................................................................................... 33 
9.5.1 
Institutional level accountability ..................................................................................... 33 
9.5.2 
Participant Level accountability .................................................................................. 3334 
 
Concomitant Therapies ....................................................................................................... 3334 
9.6.1 
Off limits ......................................................................................................................... 34 
 
Premature Discontinuation of Study Drug ......................................................................... 3435 
10. 
STUDY PROCEDURES ........................................................................................................... 3435 
 
Timing of procedures .......................................................................................................... 3435 
 
Visit Breakdown ..................................................................................................................... 35 
10.2.1 
Visit 1 – Screening ...................................................................................................... 35 
10.2.2 
Visit 2 – Baseline ..................................................................................................... 3536 


 
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10.2.3 
Visit 3 – 3months ..................................................................................................... 3637 
10.2.4 
Visit 4 – 3months post washout ............................................................................... 3738 
10.2.5 
Visit 5 – 6months – END OF STUDY .................................................................... 3839 
11. 
Summary of Tests ...................................................................................................................... 3940 
 
FMD.................................................................................................................................... 3940 
 
PAT ..................................................................................................................................... 3940 
 
Traditional Cardiovascular Risk Factors: ............................................................................... 40 
11.3.1 
Justification of Traditional Cardiovascular Risk Factors: ....................................... 4041 
 
RA Disease-Specific Risk Factors: ..................................................................................... 4142 
11.4.1 
Justification of RA Disease-Specific Risk Factors: ..................................................... 42 
 
Urine Pregnancy Test ......................................................................................................... 4243 
 
Serum Biomarkers .............................................................................................................. 4243 
12. 
EFFICACY .................................................................................................................................... 43 
 
The Primary Efficacy Outcome measures will be: ................................................................. 43 
 
Secondary Efficacy measurements ..................................................................................... 4344 
13. 
PHARMACOKINETICS ........................................................................................................... 4344 
14. 
SAFETY .................................................................................................................................... 4344 
 
Definition of adverse event (AE)........................................................................................ 4344 
 
Definition of serious adverse event (SAE) ......................................................................... 4445 
 
Category.............................................................................................................................. 4546 


 
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Outcome.............................................................................................................................. 4546 
 
Severity / Intensity .................................................................................................................. 46 
 
Relationship to Study.......................................................................................................... 4647 
 
Impact on Study Drug Administration ............................................................................... 4748 
 
Serious Adverse Events ...................................................................................................... 4748 
14.8.1 
Reporting ................................................................................................................. 4748 
14.8.2 
Unanticipated Problems ........................................................................................... 4849 
14.8.3 
Subsequent Change to Study Treatment .................................................................. 4950 
 
Expected adverse events ......................................................................................................... 50 
As per the Sildenafil package insert: .................................................................................................... 50 
14.9.1 
Pregnancy testing ..................................................................................................... 5051 
15. 
STATISTICAL METHODS .......................................................................................................... 51 
 
Statistical Methods for Specific Aims .................................................................................... 51 
 
Sample Size Justification ........................................................................................................ 52 
 
POTENTIAL PITFALLS AND SOLUTIONS ...................................................................... 53 
15.3.1 
How will we account for the potential variability in results of brachial artery FMD 
measurements? .................................................................................................................................. 53 
15.3.2 
What if study subject recruitment and retention rates are slower and/or less than 
anticipated? 53 


 
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15.3.3 
How will the effect of comorbidities and RA disease-related factors that affect 
endothelial function be mitigated so as not to confound the results of sildenafil’s effect on 
endothelial function? ......................................................................................................................... 53 
15.3.4 
Will potential effects of sildenafil risk un-blinding due to altered erectile function or 
headaches? 54 
 
Interim Analyses ..................................................................................................................... 54 
16. 
QUALITY ASSURANCE ......................................................................................................... 5455 
 
Data recording .................................................................................................................... 5455 
 
Archiving ................................................................................................................................ 55 
 
Publication Policy ................................................................................................................... 55 
 
Confidentiality / HIPAA ..................................................................................................... 5556 
 
Ethical and legal conduct of the study .................................................................................... 56 
 
Subject information and consent ............................................................................................ 56 
 
 
 


 
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1. 
PROTOCOL SYNOPSIS 
Title 
     Does Sildenafil Improve Endothelial Dysfunction in Rheumatoid 
Arthritis? 
Short title 
SEDRA 
Clinical study phase 
II 
Study objective(s) 
The primary objective of this study is to determine whether 
sildenafil use in rheumatoid arthritis (RA) patients leads to 
improvement in parameters of vascular function and to confirm its 
safety profile.  
Test drug(s) 
Sildenafil 
Name of active ingredient 
Sildenafil  
Dose(s) 
50 mg once daily 
Route of administration 
Oral 
Duration of treatment 
3 months  
Reference drug(s) 
Placebo 
Name of active ingredient 
Not applicable 
Dose(s) 
Matching placebo tablets to sildenafil 50 mg once daily 
Route of administration 
Oral 
Duration of treatment 
3 months 
Background treatment 
Not applicable 
Indication 
RA patients with no known history of cardiovascular disease(CVD), 
but at least one traditional cardiovascular (CV) risk factor in 
addition to their RA 


 
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Diagnosis and main criteria 
for inclusion 
a. Meets 2010 American College of Rheumatology (ACR) 
classification criteria1 for diagnosis of RA 
b. Aged 18 years or older 
c. No known history of CVD (see Exclusion Criteria) 
d. At least one traditional CV risk factor (i.e., older age [men ≥45 
years, women ≥55 years], obesity [defined as body mass index 
(BMI) >30 kg/m2], smoking, hypertension, hyperlipidemia, 
diabetes mellitus, family history of premature [defined as diagnosed 
at <65 years old] CVD in first-degree relative) 
e. On stable baseline doses of RA medications, defined as no change 
in dose within past 4 weeks and no anticipated changes over the 
next 6 months 
f. On no higher than 10 mg per day of prednisone or prednisone-
equivalent within past 4 weeks 
g. RA disease duration (from symptom onset) of more than 6 months 
h. Having clinical disease activity index (CDAI) of >2.8 but ≤22 (i.e., 
either low or moderate disease activity), within 30 days of study 
enrollment 
Study design 
6-month prospective phase II, single-center, randomized double-
blind, placebo-controlled crossover single-center efficacy trial 
Methodology 
This study is designed to investigate the efficacy and safety of 
sildenafil 50 mg once daily in RA patients with no known history of 
CVD, but at least one traditional CV risk factor.  Patients will be 
randomized 1:1 to receive either sildenafil or placebo for 3 months, 
then after a 2-week washout, crossed over to each respective group 
for an additional 3 months.  Vascular studies validated in assessing 
endothelial dysfunction (brachial artery flow-mediated dilation 
[FMD]2-4 and peripheral arterial tone [PAT])5 and laboratory studies 
for selected atherosclerosis biomarkers will be performed at 
baseline, 3 months pre- and post-washout, and 6 months.  Adverse 
events will be collected to assess sildenafil’s safety. 


 
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Type of control 
Placebo  
Number of subjects 
Up to 80 randomized subjects (to achieve final total of 60 subjects 
after expected ~20% drop-out) 
Primary variable 
Vascular function, determined through brachial arterial flow-
mediated dilation (FMD) and peripheral arterial tone (PAT) 
Plan for statistical analysis 
For the primary variable, treatment group (sildenafil vs. placebo) is 
the exposure of interest, with vascular function measures: (1) 
percent increase in mean maximum brachial artery diameter 
(%BAD) using FMD (continuous), and (2) mean PAT ratio 
(continuous) using EndoPAT 2000, as the primary outcomes of 
interest (measured at 0, 3 months pre- and post-washout, and 6 
months).  Given the cross-over design, analyses will focus on 
within-subject comparisons of sildenafil versus placebo periods.  All 
tests will be 2-sided with α=0.05.  The analysis will use linear mixed 
models6, with a term for treatment order (i.e. randomized initially to 
sildenafil or placebo), to assess whether %BAD and mean PAT ratio 
differ significantly between the sildenafil and placebo periods within 
subjects, adjusting for treatment order and CVD risk factors, 
baseline RA and CV medication use, disease activity (CDAI) and 
duration, and baseline levels of %BAD and PAT.  Secondary 
outcomes of interest for Specific Aim 1 are the frequencies of AEs 
and SAEs.  Since the absolute numbers of these events is anticipated 
to be small, Fisher’s exact tests will be used to compare these 
frequencies between the initial sildenafil and placebo groups. 
 
 
 


 
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List of abbreviations 
ACE 
ACR 
angiotensin-converting enzyme 
American College of Rheumatology 
AE 
adverse event 
AIDS 
ALT 
acquired immunodeficiency syndrome 
alanine aminotransferase (also known as SGPT, qv) 
AST 
aspartate aminotransferase (also known as SGOT, qv)  
ARB 
 angiotensin receptor blocker 
AUC 
 area under the plasma concentration versus time curve 
BAD 
BMI 
 brachial artery diameter 
 body mass index 
BP 
CAD 
cAMP 
CCP 
CDAI 
CD40L 
cGMP 
blood pressure 
coronary artery disease 
cyclic adenosine monophosphate 
anti-cyclic citrullinated peptide antibody 
Clinical Disease Activity Index 
CD40 ligand 
cyclic guanosine monophosphate 
CI 
confidence interval 
CRF 
CRP 
case report form 
C-reactive protein 
CV 
cardiovascular 
CVD 
cardiovascular disease 
DAS28 
DM 
DMARDs 
ECG 
ED 
ELISA 
ESR 
FMD 
Disease Activity Score-28 
diabetes mellitus 
disease modifying antirheumatic drugs 
electrocardiogram 
erectile dysfunction 
enzyme linked immunosorbent assay 
erythrocyte sedimentation rate 
flow-mediated dilation 
g 
gram 
GFR 
glomerular filtration rate 
HDL 
HIPAA 
HIV 
HOMA-IR 
HR 
high density lipoprotein 
Health Insurance Portability and Accountability Act of 1996 
human immunodeficiency virus 
homeostatic model assessment of insulin resistance 
heart rate 
HRQoL 
health-related quality of life 
hsCRP 
HTN 
ICAM 
 high-sensitivity C-reactive protein 
 hypertension 
 intracellular adhesion molecule 
IDS 
 Investigational Drug Service  
IL 
IRB 
interleukin 
Institutional Review Board 
ITT 
intent to treat 


 
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kg 
kilogram 
L 
liter 
LDL 
LFTs 
Lp(a) 
MD 
low density lipoprotein 
liver function tests 
lipoprotein(a) 
medical doctor 
mg 
milligram 
ml 
milliliter 
mmHg 
MMP 
MOOP 
millimeters of mercury 
matrix metalloproteinase 
manual of operations and procedures 
MPO 
NIAMS 
 
NO 
NSAIDs 
myeloperoxidase 
National Institute of Arthritis and Musculoskeletal and Skin 
Diseases 
nitric oxide 
nonsteroidal anti-inflammatory drugs 
OHRP 
PAH 
PAT 
Office of Human Research Protections 
pulmonary arterial hypertension 
peripheral arterial tone 
PDE 
phosphodiesterase 
PDE5 
phosphodiesterase 5 
RAPID-3 
RDMS 
RF 
RHI 
 Routine Assessment of Patient Index Data-3 
 Rheumatic Disease Management System 
 rheumatoid factor 
 reactive hyperemia index 
SAE 
serious adverse event 
SAP 
statistical analysis plan 
SBP 
systolic blood pressure 
SD 
UPMC 
VCAM 
standard deviation 
University of Pittsburgh Medical Center 
vascular cell adhesion molecule 
 
 


 
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2. 
INTRODUCTION 
 
Background 
2.1.1 
CARDIOVASCULAR RISK AND ENDOTHELIAL 
DYSFUNCTION IN RA 
 Cardiovascular Risk in RA is Increased, Yet Primary CVD Preventive Care in RA is Lacking 
 We and others have previously shown that rheumatoid arthritis (RA) is independently associated 
with an approximately 2-fold increased risk of cardiovascular disease (CVD). Indeed, RA itself is 
deemed to impart a cardiovascular (CV) risk equivalent to diabetes mellitus (DM). However, unlike in 
DM, little is known about optimal adjunctive primary and secondary CV prevention strategies for the 
RA population. Inflammation is known to contribute to CVD risk in RA. Multiple studies show that 
disease modifying anti-rheumatic drugs (DMARDs) and biologic agents (e.g., tumor necrosis factor 
[TNF]-α inhibitors) can partially mitigate the increased CVD risk in RA patients. The importance of 
using these drugs to control inflammation early in RA is well recognized, both for reducing joint 
damage and long-term CVD risk. However, despite early use of these drugs to treat RA, the mortality 
gap in RA patients compared to the general population is still widening, in part due to suboptimal 
primary and secondary CVD preventive care in RA. Furthermore, negative side effects of DMARDs and 
biologic agents hinder their use as adjunctive primary CVD prevention strategies. 
 RA Patients Experience Unique Barriers to Traditional CVD Preventive Care Strategies 
In a review of statins and CVD risk in RA, it was noted that statins may be beneficial in primary 
(but not secondary) CVD prevention in RA. However, they cause more musculoskeletal and 
gastrointestinal side effects in RA patients than the general population, which limits their routine use. 
Similarly, pain and fatigue in RA patients limit their abilities to enact lifestyle changes (e.g., exercise) 
that are well-known to improve CV risk. 
 Endothelial Dysfunction: An Important “First Step” in Atherosclerosis and CV Risk in RA 
One of the most important early steps of atherogenesis is endothelial dysfunction, which also 
contributes to the progression of atherosclerotic plaque. The fundamental feature of endothelial 
dysfunction is impaired nitric oxide (NO) bioavailability, resulting in an impaired ability of the artery to 
dilate in response to physical and chemical stimuli. NO exerts cardioprotective roles by relaxing smooth 
muscle cells of the vessel wall, preventing leukocyte migration, adhesion molecule (e.g., vascular cell 
adhesion molecule [VCAM]-1, intercellular adhesion molecule [ICAM]-1) expression, and platelet 
aggregation. The degree of endothelial dysfunction has been shown in numerous clinical studies in other 


 
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high-risk populations to be closely associated with increased risk of future CVD events and adds 
prognostic value beyond traditional CV risk factors. Specifically, a recent prospective study of 528 
stable patients at high risk of CVD events showed that advanced endothelial dysfunction significantly 
correlated with near future CVD events, and adding a physiological measure of endothelial dysfunction 
to other risk classification models (e.g., Framingham score, angiographic scoring system, etc.) could be 
clinically valuable in identifying vulnerable patients.  
 Endothelial Dysfunction is Increased in RA Patients 
Recent studies have shown that atherosclerosis lesions occur earlier and have a more rapid evolution 
in RA patients than the general population. In mouse models of collagen-induced arthritis, the severity 
of endothelial dysfunction mirrored the arthritis severity. In observational human studies, subclinical 
atherosclerosis and endothelial dysfunction increased in early RA patients and RA patients without CVD 
risk factors or complications compared to controls.  
 Endothelial Dysfunction in RA: Both Inflammation and Traditional CVD Risk Factors Are 
Important 
In RA, both traditional CVD risk factors and markers of RA severity contribute to models predicting 
CVD events. Recent studies showed abnormal endothelium-independent microvascular function that 
correlates with inflammation, but is not altered by short-term anti-inflammatory therapy. Classical CVD 
risk factors and anti-tumor necrosis factor (TNF)-α medications have different effects on micro- and 
macrovascular endothelial function, suggesting combined CVD prevention approaches (i.e., treating 
both inflammation and classical CVD risk-related endothelial dysfunction) may be necessary.  
 Biomarkers of Endothelial Dysfunction in RA Correlate with Subclinical Atherosclerosis 
Biomarkers of endothelial dysfunction are significantly higher in RA patients than controls, even 
after controlling for medication use or traditional CVD risk factors. VCAM-1 has been associated with 
common carotid artery intima-media thickness (cIMT) as determined by carotid ultrasonography (US), a 
measure of subclinical atherosclerosis. In preliminary studies from my current NIH K23 award (K23 
AR061407), we have similarly found in a cross-sectional analysis that markers of endothelial 
dysfunction (ICAM-1, VCAM-1, and E-selectin) were significantly positively associated with cIMT in 
46 RA subjects and 70 controls, both overall and in the RA group alone. 
 Predictors of Endothelial Dysfunction in RA - Inflammatory Markers and Higher Disease 
Activity 


 
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Sarli et al investigated predictors of endothelial dysfunction (as measured by brachial artery 
FMD) in patients with RA in a case-control study, and found RA patients had significantly more 
endothelial dysfunction than controls. Erythrocyte sedimentation rate (ESR), disease duration, and 
disease activity score in 28 joints (DAS28) were independent predictors of impaired FMD in RA. 
 
2.1.2 
SILDENAFIL 
 Sildenafil is a Well-Suited Agent Targeting Endothelial Dysfunction  
Drugs that improve endothelial dysfunction hold promise for 
preventing CVD. Sildenafil, which has been used to treat erectile 
dysfunction (ED) and pulmonary arterial hypertension (PAH), 
enhances NO signaling by inhibiting phosphodiesterase-5 (PDE5). 
(Figure 1) In a mouse model of atherosclerosis, sildenafil restored 
endothelial function by reducing oxidative stress and plaque 
deposition in the aorta. Sildenafil has a shorter half-life (4 hours) than 
other PDE5 inhibitors (e.g., tadalafil or vardenafil), making it well-
suited for a crossover study by minimizing potential carryover 
effects. In pharmacodynamics studies, the effect of sildenafil on erectile response showed diminished 
response at 4 hours compared to 2 hours, and the effect on blood pressure in healthy volunteers was not 
different than placebo at 8 hours, irrespective of dosage. Notably, in previous PAH trials, there was 
significant clinical worsening in PAH after a 2-week washout of sildenafil.51 It is likely that sildenafil’s 
effects on the brachial vasculature would be similar to other vascular beds. Hence, the short drug activity 
effects (up to 8 hours) is unlikely to pose significant carryover effects. 
 PDE Inhibitors Have Pleiotropic Beneficial Effects and Immunomodulatory Properties 
PDE5 inhibitors like sildenafil have been shown to improve endothelial function in patients with 
PAH and DM. They have also been found to have pleiotropic beneficial effects and were safe and well-
tolerated over long-term use in patients with ED coexistent with multiple other CV comorbidities. In 
studies of patients with ED and stable CAD, sildenafil at doses of 50 mg to 100 mg while off nitrates 
improved cardiac function significantly more than placebo. Phosphodiesterases (PDE) and their 
substrates (e.g., cAMP and cGMP) are ubiquitously expressed in the immune system. PDE inhibition 
exerts anti-inflammatory activity by increasing intracellular cAMP. PDE4 inhibitors have efficacy in 
RA:  Inflammation +
Traditional CV Risk Factors
Endothelial Dysfunction:
Decreased NO signaling
Increased CV Risk
Figure 1
|---sildenafil


 
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experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis. Dual PDE4 and 
PDE7 inhibitors decreased the severity of collagen induced arthritis (CIA) in a rat model of RA. The 
PDE4 inhibitor apremilast was shown in a phase 2 clinical trial in Behcet’s disease and phase 3 human 
randomized controlled clinical trials in psoriatic arthritis to be effective, safe, and well-tolerated. Both 
psoriatic arthritis and Behcet’s are also systemic autoimmune diseases like RA. PDE5 inhibitors like 
sildenafil also have immunomodulatory actions, though human studies to date have primarily focused on 
end-organ manifestations of autoimmune diseases like PAH, Raynaud’s phenomenon, renal disease 
(e.g., IgA nephropathy), and pulmonary fibrosis. Although sildenafil is much more selective for PDE5 
(4,000-fold), it also has >700-fold selectivity for PDE4 and other PDEs; hence, it is promising as a 
potential agent to target not only endothelial dysfunction but inflammation in patients with RA. 
 
3. 
Study Drug 
 
Mechanism of Action 
 
Sildenafil is a phosphodiesterase-5 (PDE5) inhibitor. PDE5 normally breaks down the 
intracellular second messenger of NO, cGMP. Hence, PDE5 inhibition by sildenafil results in increased 
cGMP and improved endothelial function, with vascular smooth muscle cell relaxation. Sildenafil has a 
shorter half-life (4 hours) than other PDE5 inhibitors (e.g., tadalafil or vardenafil), making it well-suited 
for a crossover study by minimizing potential carryover effects. In pharmacodynamics studies, the effect 
of sildenafil on erectile response showed diminished response at 4 hours compared to 2 hours, and the 
effect on blood pressure in healthy volunteers was not different than placebo at 8 hours, irrespective of 
dosage. Notably, in previous PAH trials, there was significant clinical worsening in PAH after a 2-week 
washout of sildenafil. It is likely that sildenafil’s effects on the brachial vasculature would be similar to 
other vascular beds. Hence, the short drug activity effects (up to 8 hours) is unlikely to pose 
significant carryover effects. 
 
 
Rationale 
Rheumatoid arthritis (RA), a chronic inflammatory disorder affecting the joints, is associated with a 2-
fold increased risk of cardiovascular disease (CVD) and sudden death, which is not explained by 
traditional cardiovascular (CV) risk factors alone. CVD is a strong contributor to excess morbidity and 


 
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mortality in RA, and is likened to an extra-articular disease manifestation akin to a “rheumatoid 
vasculopathy.” Indeed, RA itself imparts a CV risk equivalent to diabetes mellitus (DM). It is well-
recognized that chronic inflammation contributes to CVD risk in RA patients. Studies show that early 
tight control of disease activity in RA reduces disability and long-term CVD risk. Yet, despite early 
treatment for RA, the mortality gap in RA compared to the general population is still widening, in part 
due to suboptimal primary and secondary CVD preventive care in RA. Hence, besides early tight disease 
control in RA, attention must now shift to adjunctive primary prevention strategies to mitigate 
CVD risk in these high-risk patients. To date, there are no published controlled intervention trials for 
primary CV prevention in RA, despite this clearly urgent unmet need. The only such trial, TRACE-RA 
(a placebo-controlled double-blind primary CVD prevention trial in RA with atorvastatin) was stopped 
prematurely due to low numbers of CVD events that occurred, underscoring the need for use of 
subclinical CVD endpoints rather than hard CVD events in such trials. 
 
One of the early stages of atherosclerosis is endothelial dysfunction, which is closely associated with 
risk of future CVD. Using drugs to target endothelial dysfunction is a promising novel strategy for CVD 
prevention. In RA, inflammation mediates premature endothelial dysfunction by activation of 
endothelial cells. The fundamental feature of endothelial dysfunction is impaired nitric oxide (NO) 
bioavailability. NO exerts cardio-protective roles by relaxing vascular smooth muscle cells and 
preventing leukocyte adhesion. Sildenafil, which is used to treat erectile dysfunction (ED) and 
pulmonary arterial hypertension (PAH), enhances NO signaling by inhibiting phosphodiesterase-5 
(PDE5). In an experimental mouse model of atherosclerosis, sildenafil restored endothelial function, 
with a 40% decrease in aortic plaque. In human studies, PDE5 inhibitors including sildenafil improved 
endothelial function in PAH and DM, and were safe and well-tolerated in those with CV co-morbidities. 
Sildenafil’s favorable safety profile has been studied longer than any other PDE5 inhibitor. Furthermore, 
PDE inhibitors have immunomodulatory properties that hold promise in treating autoimmune conditions 
like RA.  
 
Predictors of endothelial dysfunction in RA include markers of inflammation and higher disease activity. 
In RA, abnormal microvascular endothelial function correlated with inflammation, but was not altered 
by short-term anti-inflammatory therapy; hence, combined CVD-prevention approaches beyond anti-
inflammatory therapy may be necessary. In light of this background, our central hypothesis is that 


 
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sildenafil, by targeting endothelial dysfunction, may be a uniquely suited agent and novel 
adjunctive primary CVD prevention strategy in RA. Specifically, our goal is to determine if 
sildenafil use in RA patients improves endothelial dysfunction, inflammation, and atherosclerosis 
biomarkers. 
 
4. 
 Risk-Benefit assessment 
 
Benefits of Study in General:  
The benefits from the results of this study will assist in determining whether sildenafil improves 
endothelial function in RA, which may be important in arresting one of the first steps in the pathogenesis 
of atherosclerosis and development of future CVD events in RA. Such knowledge may result in a better 
understanding of the disease process and ultimately may lead to new adjunctive primary preventive and 
therapeutic approaches for cardiovascular risk associated with RA. 
 
Potential Risks of Study in General: 
Common side effects of the vascular studies (occurring in less than 25% of patients) include discomfort, 
numbness, or pain from the blood pressure cuff occluding the subject’s arm. The EndoPAT and flow 
mediated dilation tests will be done together at the same time. The subjects will be asked to lie still on 
their back during the tests; this could cause stiffness, back pain or dizziness. During the tests, the 
occlusion cuff that will be placed on the subject’s arm will stay inflated for 5 minutes. The cuff will 
squeeze the arm tightly; this could cause minor pain, possible bruising, numbness, tingling and irritation 
to the skin. If the subject experiences pain or numbness that is bothersome, s/he will be asked to alert the 
technician performing the test. During the EndoPAT test the finger probes will fit snugly over the index 
fingers and stay on for about 20 minutes. This could cause numbness, tingling and possible irritation to 
the skin. Again, if the subject experiences pain or numbness that is bothersome, s/he will be asked to 
alert the technician performing the test. 
 
 
Rare study risks (occurring in less than 1% of patients) include minor skin irritations from the ECG 
leads. 
 
To minimize these risks, a physician and emergency drugs and equipment will be readily available at the 
VCTRC site where the vascular studies will be performed. Subjects will be asked during and after the 


 
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testing how they are feeling and their responses will be noted. The test will be stopped at any point as 
per the subject’s discretion. Subjects will be monitored for gross ECG changes and arrhythmias during 
the study at all times. Continuous monitoring by pulse oximetry will be maintained during the study. 
Subjects may be monitored for 30 to 90 minutes after completion of the vascular studies. 
 
There is a small risk that confidentiality may be breached. Data will be kept confidential in a secure 
database. All forms will be stored in locked filing cabinets. Electronic data will be identified by patient 
ID only. All computer files will be protected from unauthorized access. 
 
5. 
STUDY OBJECTIVES 
 
 
Primary endpoint 
 Specific Aim 1:  To determine whether sildenafil use in RA patients leads to improvement in 
parameters of vascular function; and to confirm its safety profile. 
 
The Primary Efficacy Outcome measures will be: 
5.2.1 
Brachial Artery Flow Mediated Dilation (FMD) Without 
Nitroglycerin 
The methods of assessment of endothelial function via FMD will be performed following guidelines. 
Vascular reactivity will be measured noninvasively using vascular ultrasound imaging. Flow and 
diameter changes of the brachial artery will be assessed by Duplex ultrasound using a high-resolution 
linear array transducer. The difference between the maximum brachial artery diameter (BAD) post-
occlusion and the baseline diameter is expressed as a percentage (%BAD). Generally, %BAD values 
below 5-7% represent endothelial dysfunction, which is associated with CV risk factors, future CVD and 
mortality. Effective treatment of risk factors may improve endothelial function. Given its reversibility 
and non-invasiveness, brachial artery FMD is attractive as an assessment tool to monitor strategies to 
reduce CVD.  
 


 
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5.2.2 
Peripheral Arterial Tone (PAT) 
PAT measured by the EndoPAT 2000 device is a non-invasive method to assess endothelial function. It 
is a standardized, rapid, and easy to apply method, and has been found to correlate with multiple 
traditional CV risk factors and to be responsive to interventions. PAT is a validated alternative measure 
to brachial arterial FMD in assessing endothelial function, and is less operator-dependent than FMD. 
FMD directly measures the dilation capability of the large-conduit artery, whereas PAT measures flow 
response hyperemia, which is related to endothelial function of small arteries of microcirculation. PAT 
measures endothelium-mediated changes in vascular tone using bio-sensors placed on fingertips. 
Changes in arterial tone are elicited by creating a down-stream hyperemic response of the brachial artery 
from arm occlusion. Contra-lateral arm measurements are used to control for concurrent non-endothelial 
dependent changes in vascular tone. The semi-automatically calculated result is an index of endothelial 
function. 
 
 
5.2.3 
Safety Profile: Adverse Event Outcomes: 
All adverse event (AE) and serious adverse event (SAE) data will be collected by separate study 
personnel from those collecting other outcomes; we will document AE and SAE diagnosis, date of onset 
and resolution, severity, whether it was unexpected or related to intervention; whether the blind was 
broken; and outcome. Specific AE data will include all common side effects of sildenafil as per 
Micromedex. 
 
Secondary endpoint 
 Specific Aim 2:  To determine whether sildenafil use in RA patients is associated with 
improvement in serum atherosclerosis biomarkers.  
 
Biomarkers for endothelial dysfunction, atherosclerosis and inflammation will be measured as follows: 
 
High-sensitivity CRP (hsCRP), ESR, rheumatoid factor (RF), and anti-cyclic citrullinated peptide 
antibody (CCP) will be measured in all patients, using standard clinical laboratory protocols. Blood 
nitrite levels will be measured using chemiluminescence. The following additional selected biomarkers 


 
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involved in endothelial dysfunction and atherosclerosis will be measured in all subjects using enzyme 
linked immunosorbent assay (ELISA): leukocyte adhesion molecules (E-selectin, ICAM-1, VCAM-1), 
CD40 ligand (CD40L), interleukin-6 (IL-6), matrix metalloproteinase-9 (MMP-9), and myeloperoxidase 
(MPO). 
 
 
6. 
INVESTIGATORY TEAM 
 
PI 
 
 
 
Kimberly P. Liang, MD, MS 
Assistant Professor of Medicine 
Division of Rheumatology and Clinical Immunology 
University of Pittsburgh Medical Center 
3708 Fifth Ave., Ste. #501 
Pittsburgh, PA 15213 
Tel: (412) 383-8846 
Fax: (412) 586-3540 
 
Study Coordinator: 
 
Laurie Hope, RN 
Clinical Research Coordinator 
 
 
 
 
 
Division of Rheumatology and Clinical Immunology 
Bioscience Tower – S727 
200 Lothrop Street 
Pittsburgh, PA 15261 
Phone: (412) 648-4098 
Fax: (412) 648-4140 
Research Assistants:  
Eileen Roth / Zengbiao Qi 
 
 
 
 
Laboratory Technicians 
 
 
 
 
Division of Rheumatology and Clinical Immunology 
 
 
 
 
BST South, S754 
 
 
 
 
Pittsburgh, PA 15261 
 
 
 
 
Tel (Zengbiao’s cell): (412) 867-0016 
 
 
 
 
Tel (lab): 412-383-9838 


 
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Diane Koontz 
 
 
 
 
 
Data Project Manager 
University of Pittsburgh 
Division of Rheumatology 
S726 BST 
3500 Terrace Street 
Pittsburgh, PA 15261 
E-mail: dik4@pitt.edu 
Phone: (412) 383-8674 
Fax: (412) 648-9643 
Technologist, FMD & PAT: Jennifer Avolio, MBA, RVT  
Vascular Research Sonographer 
University of Pittsburgh Medical Center 
6NE - MUH CTRC 
Pittsburgh, PA 15213 
Phone: (412) 864-0775 
Pharmacist:                              Linda Gibson, RPh 
Investigational Drug Service Coordinator 
UPMC Presbyterian Shadyside, Presbyterian Campus Pharmacy 
3459 Fifth Avenue 
Suite E626 
Pittsburgh, PA 15213 
Phone: 412-692-2317 
Fax: 412-647-9651 
 gibsonln@upmc.edu 
NIAMS-Appointed                Elena M. Massarotti, M.D. 
Independent Safety 
 
Associate Professor of Medicine, Harvard Medical School 
Officer: 
 
 
Brigham and Women’s Hospital 
75 Francis Street, PBB-B3 
Boston, MA 02111 


 
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7. 
STUDY DESIGN 
 
Overview 
After obtaining written informed consent, eligible participants will be randomized in a 1:1 fashion to 
receive either sildenafil 50 mg orally once daily or placebo orally once daily for 3 months. After 3 
months, all subjects will undergo a 2-week washout period. Then, subjects in each group will cross over 
to the respective group (i.e., those receiving sildenafil will receive placebo, and vice versa), for an 
additional 3 months. This cross-over design will aid in recruitment feasibility and was based in part on 
known patient preferences from other trials, since all subjects will receive a potentially beneficial drug at 
some point during the study. It also allows for up to 80 recruited subjects to contribute safety data for 
Specific Aim 1. Since sildenafil has a half-life of only 4 hours and pharmacodynamics effects of only 8 
hours, and there will be a 2-week washout period, there is unlikely to be a substantial carry-over effect 
of the drug during the cross-over phase. Any potential for carry-over effect will also be accounted for by 
including treatment order in our statistical models. We will use Stata statistical software to randomly 
assign treatment status using randomized blocks of size 6.  
 
 
Phase one 
7.2.1 
Screening phase (up to 4 weeks) 
After signing the informed consent document, subjects will undergo a screening to include baseline labs 
(creatinine and LFTs and HIV and urine pregnancy test) and review of the inclusion/exclusion criteria. 
This will include the Consent & HIPAA process. 
Note: Screening and baseline can occur on the same day if clinical labs (creatinine and LFTs) have been 
drawn as part of routine care within 90 days of the baseline.  
 
 
Phase two 
7.3.1 
Initial Study Treatment phase (Month 0 to Month 3) 
Once Screening is fully satisfied, participants will proceed to the Baseline visit. At the Baseline study 
staff will dispense Study Drug. 


 
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Note: Screening and baseline can occur on the same day if clinical labs (creatinine and LFTs) have been 
drawn as part of routine care within 3 months of the baseline.  
Participants will begin use of study drug the day after baseline visit and will remain on that regimen 
(changes notwithstanding) for 3 months (+/- 7 days). 
 
 
Phase three 
7.4.1 
Washout phase (Month 3 to 2 weeks-post Month 3) 
At this visit participants will surrender their study drug supply and begin a two-week long washout 
period, after which they will return for the Crossover visit, a.k.a., 3-months plus 2-weeks, a.k.a. Visit 
Four. 
In disputes about the timing of visits the priority must go to ensuring the participant is washed-out of the 
first phase of study drug use for no less than 14 days. If that gap, for any reason, must be longer, 
justification should be provided in the study participant’s progress notes. 
7.4.2 
Crossover Treatment phase (Month 3 post 2-week-washout to 
Month 6) 
At this visit, the Month 3 plus 2-weeks post-washout visit, participants will be switched to whatever 
study drug they did not utilize in the first three months (Sildenafil to placebo or placebo to Sildenafil).  
Participants will remain in this phase, taking the crossover treatment for 3-months (+/- 7 days) 
 
7.4.3 
Termination Visit and Safety Follow-up Visit 
This is the final visit of the study. It marks the 6-month time point which is the culmination of the first 
3-month phase, the 2-week washout phase, and the second 3-month phase.  
There are no planned visits beyond the Termination visit. 
 


 
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8. 
STUDY POPULATION 
 
Inclusion criteria 
Subjects must meet the following criteria to be eligible for enrollment in the study: 
1) Meets 2010 American College of Rheumatology (ACR) classification criteria for diagnosis of 
RA (see MOOP, Appendix 2) 
 
2) Aged 18 years or older 
 
3) No known history of CVD (see Exclusion Criteria) 
 
4) At least one traditional CV risk factor (i.e.,  
a. older age [men ≥45 years, women ≥55 years],  
b. obesity [defined as body mass index (BMI) >30 kg/m2],  
c. smoking,  
d. hypertension,  
e. hyperlipidemia,  
f. diabetes mellitus,  
g. family history of premature [defined as diagnosed at <65 years old] CVD in first-degree 
relative) 
 
5) On stable baseline doses of RA medications (defined as no change in dose within past 4 weeks 
and no anticipated changes over the next 6 months) 
 
6) On no higher than 10 mg per day of prednisone or prednisone-equivalent within past 4 weeks 
(however, intra-articular corticosteroids are permitted) 
 
7) RA disease duration (from symptom onset) of more than 6 months 
 
8) Having clinical disease activity index (CDAI) of >2.8 but ≤22 (i.e., either low or moderate 
disease activity), within 30 days of study enrollment 


 
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Exclusion criteria 
Subjects who meet any of the following criteria will be excluded from enrollment in the study: 
1) Aged <18 years old 
2) Pregnant women 
3) Known personal history of CVD: clinical diagnoses of  
a. stroke,  
b. transient ischemic attack,  
c. myocardial infarction,  
d. acute coronary syndrome,  
e. peripheral arterial disease,  
f. percutaneous coronary intervention   
g. coronary bypass graft surgery 
4) Use of high-dose statins (i.e., atorvastatin 40-80 mg/day or rosuvastatin 20-40 mg/day) currently 
or within past 3 months, or any dose changes of statins or of blood pressure medications that may 
affect endothelial function (i.e., angiotensin-converting-enzyme [ACE] inhibitors or angiotensin 
receptor blockers [ARBs]) within past 3 months.  If on statin or an ACE-inhibitor or ARB, there 
should be no anticipated dose changes over the next 6 months. 
5) Persons with intra-cardiac and intra-pulmonary shunts, unstable cardiopulmonary conditions, or 
anyone on chronic oxygen therapy 
6) Persons taking nitric oxide donors, organic nitrites and nitrates, such as glyceryl trinitrate 
(nitroglycerin), sodium nitroprusside, amyl nitrite ("poppers") 


 
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7) Severe hepatic impairment (liver function tests >1.5 times upper limit of normal) within past 4 
weeks 
8) Severe impairment in renal function (serum creatinine ≥1.5 mg/dL) within past 4 weeks 
9) Hypotension (defined as blood pressure [BP] <90/60) 
10) Hereditary degenerative retinal disorders (including genetic disorders of retinal 
phosphodiesterases) 
11) Persons already taking (or taken within 3 months) sildenafil or other PDE inhibitors (i.e., 
tadalafil, vardenafil) 
12) Persons unable to provide voluntary written informed consent 
 
13) Severe hypertension (BP >170/110) 
 
14) Persons with HIV/AIDS 
 
 
 
Justification of selection criteria 
The selection criteria were carefully selected to exclude subjects from the study who may potentially be 
exposed to specific risks after administering the study drug as well as subjects with conditions that may 
have an impact on the aims of this study. 
Subjects over 65 years old will be excluded due to safety concerns regarding use of the 50 mg daily dose 
of sildenafil in this age group, and inability to achieve blinding with 25 mg daily dose due to altered 
pharmacokinetics of the drug if over-encapsulated. 
 


 
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Withdrawal of Subjects 
 
Subjects must be withdrawn from the study for the following reasons: 
 At their own request or at the request of their legally acceptable representative 
At any time during the study and without giving reasons, a subject may decline to participate 
further.  The subject will not suffer any disadvantage as a result. 
 Development of any of the exclusion criteria except for #4 (new or changed doses of CV and RA 
medications will be documented and addressed via statistical adjustment). 
 If, in the investigator's opinion, continuation of the study would be harmful to the subject's well-
being 
 Occurrence of AEs or inter-current diseases which the investigator judges unacceptable for 
continuation of participation in the study 
 Pre-specified stopping rules for adverse events:  Participants will be automatically withdrawn 
from the trial if any of the following adverse events occurs: hypotension with BP < 80/50, 
myocardial infarction, non-arteritic ischemic optic neuropathy, retinal hemorrhage, sudden 
hearing loss, priapism (prolonged penile erection), and pregnancy.   
 Occurrence of adverse drug reactions, which in the investigator’s opinion have a negative impact 
on the subject’s individual risk-benefit ratio.  
 Non-compliance with the conditions for the trial or instructions by the investigator 
 Although not preferred, subjects may interrupt their intake of study medication for reasonable 
circumstances/reasons at any time (e.g., hospitalization in a remote hospital without study 
medication access, safety reasons, and side effects). If study medication nonadherence is >50% 
by pill counts, or if the nonadherence is for 14 or more consecutive days before the study visit, 
the subject must be withdrawn. In case treatment requires interruption for> 3 days and ≤ 14 
consecutive days before the study visit, it is at the discretion of the investigator if the study 
medication can be restarted. However, any study medication nonadherence will be documented, 
and interruption of medication use for 3-45 days will be recorded as a protocol deviation. 
 In case of pregnancy or breast feeding. 


 
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 In case the subject does not tolerate the drug. 
 
Replacement of Withdrawn Subjects 
There will be no replacement of randomized subjects who withdraw from the study. 
For withdrawn subjects, certified return receipt of drug will be requested by mailing postage-paid 
mailers to the subjects, after at least three call attempts. 
 
 
Subject Identification 
After a subject signs the informed consent form, a subject identification number will be created.  This 
will be a unique code composed of study name and subject number 
First 5 letters = SEDRA (to identify with this trial) 
Last 4 digits = Unique subject number (chronologically entered in Recruitment and Screening Log) 
 
 
 
Within the Rheumatic Disease Management System (RDMS) electronic research database, each study 
subject will be assigned a random 9-digit study ID number, which will be used for source documents, 
blinded study drug dispensation, etc. 
 
Study Population Demographics 
The following demographic data will be recorded:  
 Date of birth (month and year) (age) 
 Sex 
 Race/Ethnicity 
 Socioeconomic data 
 Education level 
 Emergency Contact 
 Mailing address 
 
PARTICIPANT IDENTIFICATION 


 
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 Contact information 
 Medical History - A medical history will be collected by study personnel including all active 
conditions (and corresponding organ systems) and non-active conditions (and corresponding 
organ systems) going back one year. 
 
9. 
TREATMENT 
 
Study drug 
Test Drug: 
Sildenafil 
Dosage: 
50 mg 
Route of administration:  
oral 
Time and frequency of administration: 
once daily 
9.1.1 
Sildenafil   
Sildenafil will be supplied at 50 mg as film-coated, immediate-release tablets.  Beginning May 1, 2019, 
sildenafil will be supplied as two 20-mg and two 5-mg tablets to equal a 50 mg dose.  All study drug and 
placebo tablets will be provided through the UPMC Investigational Drug Service, who will also be 
handling patient randomization.  
 
9.1.2 
Matching placebo 
Matching placebo tablets will appear identical to active sildenafil tablets but will not contain active 
study drug. 
 
 
Justification of study drug selection 
This dose was chosen because it is the usual dose used and FDA-approved for the treatment of erectile 
dysfunction (ED), with a known favorable safety profile at that dose. Furthermore, this was the dose 
used in a double-blind, placebo-controlled, prospective trial of 24 men with type 2 diabetes with ED, 
wherein it was shown that daily use of sildenafil 50 mg/day for 10 weeks resulted in improved 
endothelial function as measured by brachial arterial FMD. 


 
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Sildenafil 50 mg orally once daily for 3 months will be provided in bottles during the sildenafil 
treatment periods. 
Placebo pills with the same size, shape, color, and texture as sildenafil will also be provided in bottles, 
to be taken orally once daily for 3 months during the placebo periods. 
 
Assignment – Randomization 
This is a randomized, double-blind, placebo-controlled, crossover, single-center study. Subjects who 
complete all screening procedures and meet all the eligibility criteria are to be randomized in a 1:1 ratio 
by the UPMC IDS. 
 
Blinding 
The study will be conducted in double-blind fashion.  Active sildenafil and placebo tablet formulations 
will be identical in appearance (size, shape, color) and smell. The packaging and labeling will be 
designed to maintain blinded conditions for the investigator and the study team.  The study data will 
remain blinded until database lock. 
9.4.1 
Allocation Concealment and Blinding 
The study will be blinded such that neither the investigator(s) nor the subject(s) will know the allocation 
assignment. To ensure enforcement of this, a biostatistician not involved with patient care will generate 
the treatment status randomization list using Stata (Stata Corp, USA). The randomization sequence will 
be kept confidential by an independent data handler. A secure password-protected electronic database 
will be used for eligibility confirmation and allocation assignment. Different study personnel will collect 
adverse event data vs. outcome data, to minimize risk of unblinding. Criteria for breaking the blinding 
will include adverse risk benefit profiles in either group, as determined by the Institutional Review 
Board and/or safety monitor. 
 
9.4.2 
Emergency Unblinding 
In case of emergency, the investigator is permitted to unblind individual cases.  However, this will be 
restricted to cases of emergency where the unblinding result is of importance for the acute treatment 
strategy.  The occurrence of an SAE should not routinely precipitate the immediate unblinding of the 


 
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label. Date, time, and reason for unblinding will be captured.  Unblinding will be coordinated through 
the Investigational Drug Service. 
 
 
Drug logistics and Accountability 
Drug logistics and accountability 
9.5.1 
Institutional level accountability 
Management of Study Drug, its ordering, receipt, storage, maintenance, dispensing, destruction and 
record-keeping will be maintained by the UPMC Investigational Drug Service (UPMC IDS). This will 
include a complete record of batch numbers and expiration dates of all study treatment, as well as the 
labels, will be maintained by the UPMC IDS. 
 
9.5.2 
Participant Level accountability 
A drug dispensing log will be completed for each subject. Subjects will receive all study medication 
dispensed at the baseline visit and again at the Month 3 post-washout visit.  At months 3 and 6, subjects 
will be instructed to bring all study drug packaging, including unused study drug and empty packaging, 
to the investigative site.  Tablets will be counted for a compliance check and drug accountability.  When 
Study Drug is returned to the site, study staff will return all study drug related materials back to the 
UPMC IDS for management. 
 If the participant misses a dose 
If a dose of study drug is missed, the subject should take a dose immediately if on the same day.  
Otherwise, they can resume normal once daily dosing the following day.  The dose should not be 
doubled to make up for a missed dose within the same day.  
 
 
Concomitant Therapies 
The following must be avoided during the timeframe in which subjects are taking the study drug 
therapy. 


 
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9.6.1 
Off limits 
Nitrates or NO donors (such as amyl nitrate) in any form, including topical; phosphodiesterase (PDE) 5 
(PDE5) inhibitors (such as sildenafil, tadalafil, vardenafil); and nonspecific PDE inhibitors 
(theophylline, dipyridamole) are prohibited. 
 
Glucocorticoid maintenance dose increases to higher than 10 mg/day for past 4+ weeks and/or any 
change or initiation of new DMARDs or biologic agents between study visits will be collected. Subjects 
with either of these medication changes will be withdrawn. We anticipate the number of subjects 
requiring RA medication changes to be small, since the inclusion criteria mandates that subjects be on 
stable doses of RA medications with no anticipated changes over the next 6 months. 
 
 
Premature Discontinuation of Study Drug 
In the event of premature discontinuation of study drug treatment, subjects must undergo the same 
procedures as outlined for the Month 6 end of study visit.   
  
10. 
STUDY PROCEDURES 
 
Timing of procedures 
Screening and baseline visits can occur on the same day. 
 Visit Windows 
There are windows of time specific to any given visit in which the visit may take place without deviating 
from the protocol by being “Late” or “Early”.  
 Baseline Visit must occur within 28 days of Screening, otherwise, Screening must be repeated. 
 Three Month Visit must occur three months +/- 7 days after Baseline 
 The Two Week Washout Visit must take place between fourteen and seventeen days after Three 
Month Visit 
 Six Month Visit must occur three months +/- 7 days after the Two Week Washout Visit 


 
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Visit Breakdown 
10.2.1 
Visit 1 – Screening 
Screening evaluations will occur after the subject has provided written informed consent.  The following 
evaluations will be performed and information obtained up to 28 days before baseline randomization and 
the start of study drug treatment: 
 Patient information and obtaining of written informed consent 
 Eligibility: Assessment of inclusion and exclusion criteria  
 Demographic data, including age, gender and ethnicity 
 Complete medical history (obtained through patient interview and medical record review) 
 Liver function tests and creatinine with GFR.  Labs obtained as part of routine clinical care up to 
3 months prior to screening will be accepted.   
 HIV 1/2  test (results within 3 months prior to screening will be accepted) 
If re-screening is required, the liver function tests, creatinine, HIV 1/2 test results, and urine pregnancy 
test (if applicable) from the previous screening visit may be used if no longer than 3 months prior. 
10.2.2 
Visit 2 – Baseline 
The following assessments will be performed at the Baseline visit (Day 0 of study drug treatment): 
 Reconfirmation of eligibility (assessment of inclusion/exclusion criteria), if performed at 
separate visits 
 Cardiovascular history and assessment of CV risk factors 
 Assessment of RA Disease Activity (questionnaires) 
o Routine Assessment of Patient Index Data (RAPID-3) 
o DAS28 
o CDAI (including tender and swollen joint counts, patient and assessor VAS) 
 Additional RA Questionnaires 
o RA medications 
o RA disease duration (calculated from date of symptom onset) 
 Vital signs (blood pressure x3, heart rate, height, weight, waist:hip circumference) 


 
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 Vascular Imaging (to be performed simultaneously) 
o Brachial FMD 
o EndoPAT 
 Pregnancy test (urine) for all women of childbearing potential  
 Blood sample (at least 4-hr fasting) 
o Biomarkers (hsCRP, ESR, RF, CCP, E-selectin, ICAM-1, VCAM-1, CD40L, IL-6, 
MMP-9, and MPO) 
o Nitrite levels 
o Total cholesterol, LDL, HDL, Triglycerides, Homocysteine, Lipoprotein A 
o Glucose and insulin 
 Recording and assessment of AEs  
 Recording of Concomitant therapy (including CV medications) 
 Randomization to initial sildenafil or placebo  
 Dispense study drug 
 
10.2.3 
Visit 3 – 3months 
 Reconfirmation of eligibility (assessment of inclusion/exclusion criteria), if performed at 
separate visits 
 Cardiovascular history and assessment of CV risk factors 
 Assessment of RA Disease Activity (questionnaires) 
o Routine Assessment of Patient Index Data (RAPID-3) 
o DAS28 
o CDAI (including tender and swollen joint counts, patient and assessor VAS) 
 Additional RA Questionnaires 
o RA medications 
o RA disease duration (calculated from date of symptom onset) 
 Vital signs (blood pressure x3, heart rate, height, weight, waist:hip circumference) 
 Vascular Imaging (to be performed simultaneously) 
o Brachial FMD 
o EndoPAT 


 
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 Pregnancy test (urine) for all women of childbearing potential 
 Blood sample (at least 4-hr fasting) 
o Biomarkers (hsCRP, ESR, RF, CCP, E-selectin, ICAM-1, VCAM-1, CD40L, IL-6, 
MMP-9, and MPO) 
o Nitrite levels 
o Total cholesterol, LDL, HDL, Triglycerides, Homocysteine, Lipoprotein A 
o Glucose and insulin 
 Recording and assessment of AEs 
 Recording of Concomitant therapy (including CV medications) 
 Study Drug Compliance 
 Two-week study drug washout period begins the day after the last pill was taken 
 
10.2.4 
Visit 4 – 3months post washout 
 Reconfirmation of eligibility (assessment of inclusion/exclusion criteria), if performed at 
separate visits 
 Cardiovascular history and assessment of CV risk factors 
 Assessment of RA Disease Activity (questionnaires) 
o Routine Assessment of Patient Index Data (RAPID-3) 
o DAS28 
o CDAI (including tender and swollen joint counts, patient and assessor VAS) 
 Additional RA Questionnaires 
o RA medications 
o RA disease duration (calculated from date of symptom onset) 
 Vital signs (blood pressure x3, heart rate, height, weight, waist:hip circumference) 
 Vascular Imaging (to be performed simultaneously) 
o Brachial FMD 
o EndoPAT 
 Pregnancy test (urine) for all women of childbearing potential 
 Blood sample (at least 4-hr fasting) 


 
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o Biomarkers (hsCRP, ESR, RF, CCP, E-selectin, ICAM-1, VCAM-1, CD40L, IL-6, 
MMP-9, and MPO) 
o Nitrite levels 
o Total cholesterol, LDL, HDL, Triglycerides, Homocysteine, Lipoprotein A 
o Glucose and insulin 
 Recording and assessment of AEs 
 Recording of Concomitant therapy (including CV medications) 
 Dispense Study Drug 
 
10.2.5 
Visit 5 – 6months – END OF STUDY 
 Reconfirmation of eligibility (assessment of inclusion/exclusion criteria), if performed at 
separate visits 
 Cardiovascular history and assessment of CV risk factors 
 Assessment of RA Disease Activity (questionnaires) 
o Routine Assessment of Patient Index Data (RAPID-3) 
o DAS28 
o CDAI (including tender and swollen joint counts, patient and assessor VAS) 
 Additional RA Questionnaires 
o RA medications 
o RA disease duration (calculated from date of symptom onset) 
 Vital signs (blood pressure x3, heart rate, height, weight, waist:hip circumference) 
 Vascular Imaging (to be performed simultaneously) 
o Brachial FMD 
o EndoPAT 
 Pregnancy test (urine) for all women of childbearing potential 
 Blood sample (at least 4-hr fasting) 
o Biomarkers (hsCRP, ESR, RF, CCP, E-selectin, ICAM-1, VCAM-1, CD40L, IL-6, 
MMP-9, and MPO) 
o Nitrite levels 
o Total cholesterol, LDL, HDL, Triglycerides, Homocysteine, Lipoprotein A 
o Glucose and insulin 


 
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 Recording and assessment of AEs  
 Recording of Concomitant therapy (including CV medications) 
 Study Drug Compliance 
 
11. 
 Summary of Tests 
 
FMD 
Brachial Artery Flow Mediated Dilation (FMD) Without Nitroglycerin 
The methods of assessment of endothelial function via FMD will be performed following guidelines. 
Vascular reactivity will be measured noninvasively using vascular ultrasound imaging. Flow and 
diameter changes of the brachial artery will be assessed by Duplex ultrasound using a high-resolution 
linear array transducer. The difference between the maximum brachial artery diameter (BAD) post 
occlusion and the baseline diameter is expressed as a percentage (%BAD). Generally, %BAD values 
below 5-7% represent endothelial dysfunction, which is associated with CV risk factors, future CVD and 
mortality. Effective treatment of risk factors may improve endothelial function.17 Given its reversibility 
and non-invasiveness, brachial artery FMD is attractive as an assessment tool to monitor strategies to 
reduce CVD.  
 
 
PAT 
Peripheral Arterial Tone (PAT) 
PAT measured by the EndoPAT 2000 device is a non-invasive method to assess endothelial function. It 
is a standardized, rapid, and easy to apply method, and has been found to correlate with multiple 
traditional CV risk factors and to be responsive to interventions. PAT is a validated alternative measure 
to brachial arterial FMD in assessing endothelial function, and is less operator-dependent than FMD. 
FMD directly measures the dilation capability of the large-conduit artery, whereas PAT measures flow 
response hyperemia, which is related to endothelial function of small arteries of microcirculation. PAT 
measures endothelium-mediated changes in vascular tone using bio-sensors placed on fingertips. 
Changes in arterial tone are elicited by creating a down-stream hyperemic response of the brachial artery 
from arm occlusion. Contra-lateral arm measurements are used to control for concurrent non-endothelial 


 
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dependent changes in vascular tone. The semi-automatically calculated result is an index of endothelial 
function. 
 
Cardiovascular Risk Factors: 
Information will be obtained on  
 
age 
 
sex  
 
race/ethnicity 
 
socioeconomic data 
 
smoking 
 
family history of premature CVD 
 
physical activity level 
 
menopausal status 
 
use of estrogen replacement therapy 
 
diabetes 
 
fasting glucose and insulin levels measured to calculate the homeostatic model assessment of insulin 
resistance (HOMA-IR)  
 
Body mass index (BMI) 
 
waist-to-hip (W:H) ratios  
 
Blood pressure at each of the four Study Visits #2-5 will be determined using an average of 3 consecutive 
sitting blood pressure readings  
 
Blood tests: 
o Levels of total cholesterol 
o low density lipoprotein (LDL) (LDL will be estimated with the Friedewald equation)  
o high density lipoprotein (HDL)  
o triglycerides, homocysteine  
o lipoprotein (a) 
11.3.1 
Justification of Cardiovascular Risk Factors: 
Information will be obtained on age, sex, race/ethnicity, socioeconomic data, smoking, family history of 
premature CVD, physical activity level, menopausal status, use of estrogen replacement therapy, 
diabetes, and fasting glucose and insulin levels measured to calculate the homeostatic model assessment 
of insulin resistance (HOMA-IR). Body mass index (BMI) and waist-to-hip (W:H) ratios will be 


 
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obtained. Blood pressure at each of the four Study Visits #2-5 will be determined using an average of 3 
consecutive sitting blood pressure readings. Levels of total cholesterol, low density lipoprotein (LDL), 
high density lipoprotein (HDL), triglycerides, homocysteine, and lipoprotein (a) will be measured. LDL 
will be estimated with the Friedewald equation.  
 
Use of statins, ACE-inhibitors, and ARBs including dosages and any dose changes will be recorded. 
Subjects with any of these medication changes will be recorded as a procotol deviation but will not be 
withdrawn from the study. We anticipate the number of subjects requiring CV medication changes to be 
small, since the inclusion criteria mandates that subjects be on stable doses of these CV medications 
with no anticipated changes over the next 6 months. 
 
RA Disease-Specific Risk Factors: 
The following validated RA disease activity data will be collected at each study visit:  
 Routine Assessment of Patient Index Data (RAPID-3) (a modified health assessment 
questionnaire and patient visual analogue scales)  
 DAS28 
 CDAI  
 RA medication use will be collected at each study visit, including any new medications or dose 
adjustments made. A complete list of these medications can be found on the RA Medications 
List CRF. They include  
o DMARDs 
o biologic agents 
o glucocorticoids  
o non-steroidal anti-inflammatory drugs (NSAIDs) 
o Cox-2 inhibitors 
Glucocorticoid maintenance dose increases to higher than 10 mg/day for past 4+ weeks and/or any 
change or initiation of new DMARDs or biologic agents between study visits will be collected. Subjects 
with either of these medication changes will be recorded as a procotol deviation but will not be 


 
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withdrawn from the study. We anticipate the number of subjects requiring RA medication changes to be 
small, since the inclusion criteria mandates that subjects be on stable doses of RA medications with no 
anticipated changes over the next 6 months.  
RA disease duration from symptom onset will be collected. 
11.4.1 
Justification of RA Disease-Specific Risk Factors: 
The following validated RA disease activity data will be collected at each study visit: (a) Routine 
Assessment of Patient Index Data (RAPID-3) (a modified health assessment questionnaire and patient 
visual analogue scales); (b) DAS28; and (c) CDAI. RA medication use will be collected at each study 
visit, including any new medications or dose adjustments made. These include DMARDs, biologic 
agents, glucocorticoids, non-steroidal anti-inflammatory drugs (NSAIDs), and Cox-2 inhibitors. 
Glucocorticoid maintenance dose increases to higher than 10 mg/day for past 4+ weeks and/or any 
change or initiation of new DMARDs or biologic agents between study visits will be collected. Subjects 
with either of these medication changes will be recorded as protocol deviations but will not be 
withdrawn. We anticipate the number of subjects requiring RA medication changes to be small, since 
the inclusion criteria mandates that subjects be on stable doses of RA medications with no anticipated 
changes over the next 6 months. RA disease duration from symptom onset will be collected. 
 
 
Urine Pregnancy Test 
Urine Pregnancy tests will be performed on women of child bearing potential at each study visit. 
Participants in this category will be advised to use at least one verifiable form of birth control during the 
course of the study to prevent pregnancy and for two weeks after Termination whether termination is 
early or on schedule. 
 Note: if Screening and Baseline are performed simultaneously, only one Urine Pregnancy Test 
and verification of birth control check are necessary. 
 
 
Serum Biomarkers 
High-sensitivity CRP (hsCRP), ESR, rheumatoid factor (RF), and anti-cyclic citrullinated peptide 
antibody (CCP) will be measured in all patients, using standard clinical laboratory protocols. Whole 


 
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blood nitrite levels (a measure of NO) will be measured using chemiluminescence. The following 
additional selected biomarkers involved in endothelial dysfunction and atherosclerosis will be measured 
in all subjects using enzyme linked immunosorbent assay (ELISA): leukocyte adhesion molecules (E-
selectin, ICAM-1, VCAM-1), CD40 ligand (CD40L), interleukin-6 (IL-6), matrix metalloproteinase-9 
(MMP-9), and myeloperoxidase (MPO). 
 
12. 
EFFICACY 
For more details about the Efficacy measures see 11 above 
 
The Primary Efficacy Outcome measures will be: 
 Brachial Artery Flow Mediated Dilation (FMD) Without Nitroglycerin 
 Peripheral Arterial Tone (PAT) 
 
Secondary Efficacy measurements 
 Serum Biomarkers 
 
13. 
PHARMACOKINETICS 
 
DOES NOT APPLY TO THIS STUDY 
 
14. 
SAFETY 
 
Definition of adverse event (AE) 
In a clinical study, an AE is any untoward medical occurrence (i.e., any unfavorable and unintended sign 
[including abnormal laboratory findings], symptom or disease) in a patient or clinical investigation 
subject after providing written informed consent for participation in the study.  Therefore, an AE may or 
may not be temporally or causally associated with the use of a medicinal (investigational) product. 


 
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In the following differentiation between medical history and AEs, the term “condition” may include 
abnormal e.g., physical examination findings, symptoms, diseases, laboratory, ECG. 
 Conditions that started before signing of informed consent and for which no symptoms or 
treatment are present until signing of informed consent will be recorded as medical history (e.g., 
seasonal allergy without acute complaints). 
 Conditions that started before signing of informed consent and for which symptoms or treatment 
are present after signing of informed consent, at unchanged intensity, will be recorded as medical 
history (e.g., allergic pollinosis). 
 Conditions that started or deteriorated after signing of informed consent will be documented as 
AEs. 
 
Definition of serious adverse event (SAE) 
An SAE is classified as any untoward medical occurrence that, at any dose, meets any of the following 
criteria (a – f): 
a. Results in death 
b. Is life-threatening 
The term ‘life-threatening’ in the definition refers to an event in which the subject was at risk of 
death at the time of the event, it does not refer to an event which hypothetically might have 
caused death if it were more severe. 
c. Requires inpatient hospitalization or prolongation of existing hospitalization 
A hospitalization or prolongation of hospitalization will not be regarded as an SAE if at least 
one of the following exceptions is met: 
- The admission results in a hospital stay of less than 12 hours 
- The admission is pre-planned  
(i.e., elective or scheduled surgery arranged prior to the start of the study) 
- The admission is not associated with an AE  
(e.g., social hospitalization for purposes of respite care). 


 
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However, it should be noted that invasive treatment during any hospitalization may fulfill the 
criterion of ‘medically important’ and as such may be reportable as an SAE dependent on 
clinical judgment.  In addition, where local regulatory authorities specifically require a more 
stringent definition, the local regulation takes precedence. 
d. Results in persistent or significant disability / incapacity 
Disability means a substantial disruption of a person’s ability to conduct normal life’s functions. 
e. Is a congenital anomaly / birth defect 
f. Is another medically important serious event as judged by the investigator 
 
 
Category 
Adverse Events will be categorized by body system utilizing the NIH category system found at 
https://safetyprofiler-ctep.nci.nih.gov/ 
 
Outcome 
The outcome of the AE is to be documented as follows:  
- Recovered, without treatment 
- Recovered, with treatment 
- Still present, no treatment 
- Still present, being treated 
- Residual effect(s) present, no treatment 
- Residual effect(s) present, being treated 
- Subject died 
 


 
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Severity / Intensity 
The intensity of an AE is classified according to the following categories: 
- Mild 
- Moderate 
- Severe 
Mild is defined as asymptomatic or mild symptoms; intervention not indicated. 
Moderate is defined as moderate symptoms present; only minimal intervention indicated. 
Severe is defined as severe or medically significant symptoms requiring hospitalization or urgent 
intervention. 
 
 
Relationship to Study  
The assessment of the causal relationship between an AE and the administration of treatment is a 
clinical-decision based on all available information.  The assessment is based on the question whether 
there was a “reasonable causal relationship” to the study treatment in question. 
An assessment of “not related” is defined as an adverse event being clearly not related or unlikely to be 
related.  Adverse events can also be attributed as “possible/probable” defined as reasonably possible or 
likely to be related, or “definite” defined as the adverse event is clearly related.   
Important factors to be considered in assessing the relationship of the AE to study treatment include: 
- The temporal sequence from drug administration:  The event should occur after the drug is given.  
The length of time from drug exposure to event should be evaluated in the clinical context of the 
event. 
- Recovery on drug discontinuation (de-challenge), recurrence on drug re-introduction (re-challenge): 
- Subject’s response after de-challenge or subjects response after re-challenge should be considered in 
the view of the usual clinical course of the event in question. 


 
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- Underlying, concomitant, intercurrent diseases:   
Each event should be evaluated in the context of the natural history and course of the disease being 
treated and any other disease the subject may have. 
- Concomitant medication or treatment:  
The other drugs the subject is taking or the treatment the subject receives should be examined to 
determine whether any of them may be suspected to cause the event in question. 
- The pharmacology and pharmacokinetics of the study treatment:  
The pharmacokinetic properties (absorption, distribution, metabolism and excretion) of the study 
treatment, coupled with the individual subject’s pharmacodynamics should be considered. 
 
Impact on Study Drug Administration 
Any action on study treatment to resolve the AE is to be documented using the categories listed below. 
o Drug withdrawn 
o Drug interrupted 
o Not applicable 
o Unknown 
 
 
Serious Adverse Events 
14.8.1 
Reporting 
 Sponsor 
 
 
 
 
Pfizer is the provider of the study drug Sildenafil and its placebo (“drug sponsor”). Serious Adverse 
Events must be reported to the drug sponsor utilizing the forms provided by Pfizer and in accordance 
with the guide they have provided. These items can be found in the Manual of Operations and 
Procedures (MOOP) under Safety Reporting. 
 
 Independent Safety Officer 


 
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Investigator’s notification to the Independent Safety Officer 
All SAEs occurring during the observation period defined in Section 14.8 must immediately (within 
48 hours of the investigator’s awareness) be reported to KAI, NIAMS and the independent Safety 
Officer.  An SAE form must also be completed within 48 hours of the investigator awareness and 
forwarded.  Each SAE must be followed up until resolution or stabilization by submission of updated 
reports.   
 
 IRB 
Notification of the IRB 
Notification of the University of Pittsburgh IRB about all relevant events (e.g., SAEs, suspected, 
unexpected, serious adverse reactions [SUSARs]) will be performed according to IRB regulations.   
 
 
14.8.2 
Unanticipated Problems 
The phrase “unanticipated problems involving risks to subjects or others” is found but not defined in the 
HHS regulations at 45 CFR part 46.  OHRP considers unanticipated problems, in general, to include any 
incident, experience, or outcome that meets all of the following criteria: 
1. 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 subject population being studied;  
2. related or possibly related to participation in the research (in this guidance document, possibly 
related means there is a reasonable possibility that the incident, experience, or outcome may have been 
caused by the procedures involved in the research); and 
3. suggests that the research places subjects or others at a greater risk of harm (including physical, 
psychological, economic, or social harm) than was previously known or recognized. 
 Reporting 
 Independent Safety Officer 


 
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Investigator’s notification to the Independent Safety Officer 
All Unanticipated Problem occurring during the observation period defined in Section must immediately 
(within 48 hours of the investigator’s awareness) be reported to KAI, NIAMS and the independent 
Safety Officer.  An Unanticipated Problem form must also be completed within 48 hours of the 
investigator awareness and forwarded.  Each Unanticipated Problem must be followed up until 
resolution or stabilization by submission of updated reports 
 IRB 
Notification of the IRB 
Notification of the University of Pittsburgh IRB about all relevant events (e.g., SAEs, suspected, 
unexpected, serious adverse reactions [SUSARs*]) will be performed according to IRB regulations.   
*A SERIOUS UNEXPECTED SERIOUS ADVERSE REACTION (SUSAR) is an unexpected adverse 
reaction (UAR) is an adverse reaction that is not consistent with the product information. A suspected 
unexpected serious adverse reaction (SUSAR) is any UAR that at any dose:  
• results in death;  
• is life threatening (i.e. the subject was at risk of death at the time of the event; it does not refer to an 
event which hypothetically might have caused death if it were more severe);  
• requires hospitalization or prolongation of existing hospitalization;  
• results in persistent or significant disability or incapacity;  
• is a congenital anomaly or birth defect. 
 
 
 
14.8.3 
Subsequent Change to Study Treatment 
If changes to the administration of the study drug occur (e.g. changes in response to an Adverse Event, 
poor compliance with study drug, missing/lost study drug, etc) these are to be reported to the drug 
sponsor and noted in the appropriate form (Adverse Events, Serious Adverse Event, Unanticipated 
Problem, etc).  
 
 Reporting to INDEPENDENT SAFETY OFFICER 
Any such changes to Study Treatment that involve unfavorable changes to the risk benefit ratio should 
be reported to the Independent Safety Officer. 
 


 
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Expected adverse events 
As per the Sildenafil package insert:  
 
“When VIAGRA was taken as recommended (on an as-needed basis) in flexible-dose, 
placebo-controlled clinical trials, the following adverse events were reported: 
 
TABLE 2. ADVERSE EVENTS REPORTED BY 2% OF PATIENTS TREATED WITH VIAGRA 
AND MORE FREQUENT ON DRUG THAN PLACEBO IN PRN FLEXIBLE-DOSE PHASE II/III 
STUDIES 
Adverse Event Percentage of Patients Reporting Event 
 
 
VIAGRA
PLACEBO
N=734
N=725
Headache
16%
4%
Flushing
10%
1%
Dyspepsia
7%
2%
Nasal Congestion
4%
2%
Urinary Tract Infection
3%
2%
Abnormal Vision† 
3% 
0% 
Diarrhea
3%
1%
Dizziness
2%
1%
Rash
2%
1%
†Abnormal Vision: Mild and transient, predominantly color tinge to vision, but also increased sensitivity to light or blurred 
vision. In these studies, only one patient discontinued due to abnormal vision. 
 
Other adverse reactions occurred at a rate of >2%, but equally common on placebo: respiratory 
infection, back pain, flu syndrome, and arthralgia.” 
 
These common events will be noted as Adverse Events if they occur, but may be noted as 
“EXPECTED” on the Adverse Events Log. 
14.9.1 
Pregnancy testing 
Pregnancy testing is to be performed at the Screening visit.  In the event of pregnancy, a referral to a 
gynecologist for confirmation of pregnancy will be promptly organized.  Further consequences with 
regard to ongoing participation in the study must be discussed with the patient.  
Women of childbearing potential and non-vasectomized male participants must agree to use adequate 
contraception when sexually active.  ‘Adequate contraception’ is defined as any combination of at 
least 2 effective methods of birth control, of which at least one is a physical barrier (e.g. condoms with 


 
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hormonal contraception or implants or combined oral contraceptives, certain intrauterine devices).  The 
exception will be women who have undergone tubal ligation and men who have undergone a vasectomy. 
15. 
STATISTICAL METHODS 
 
General considerations 
Baseline variables will be summarized with appropriate descriptive statistics within each starting 
treatment group. Significance of any differences will be assessed using the Wilcoxon rank sum (non-
normal data) or t-test for continuous data, and the chi-square test for categorical data. 
 
Statistical Methods for Specific Aims 
For Specific Aim 1, treatment group (sildenafil vs. placebo) is the exposure of interest, with vascular 
function measures: (1) percent increase in mean maximum brachial artery diameter (%BAD) using FMD 
(continuous), and (2) mean PAT ratio (continuous) using EndoPAT 2000, as the primary outcomes of 
interest (measured at 0, 3 months pre- and post-washout, and 6 months). Given the cross-over design, 
analyses will focus on within-subject comparisons of sildenafil versus placebo periods. All tests will be 
2-sided with α=0.05. 
 
The analysis will use linear mixed models, with a term for treatment order (i.e. randomized initially to 
sildenafil or placebo), to assess whether %BAD and mean PAT ratio differ significantly between the 
sildenafil and placebo periods within subjects, adjusting for treatment order and CVD risk factors, 
baseline RA and CV medication use, disease activity (CDAI) and duration, and baseline levels of 
%BAD and PAT. Model fit, appropriate assumptions (e.g. normality, linearity, homoscedasticity), and 
potential collinearity, will be assessed with standard diagnostic plots and variance inflation factors 
(VIF). If needed, we will explore corresponding transformations of the covariates, and/or (in the case of 
collinearity) dropping variables from the model. We will address any non-compliance using an 
intention-to-treat strategy and will conduct a sensitivity analysis to conservatively assess observing how 
the worst outcome would affect results. We do not anticipate many will have RA medication changes 
but those participants will be included in the analysis; a secondary sensitivity analysis will add a 
covariate (at the corresponding time point(s)) to denote (yes or no) whether medication changed during 
the course of the study. Although we recognize that different types of medication changes may have 


 
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different effects on the outcome, we will not have sufficient power to estimate heterogeneity of effects 
across different types of medication changes.  
 
Secondary outcomes of interest for Specific Aim 1 are the frequencies of AEs and SAE. Since the 
absolute numbers of these events is anticipated to be small, Fisher’s exact tests will be used to compare 
these frequencies between the initial sildenafil and placebo groups. 
 
For Specific Aim 2, treatment group is again the exposure of interest, with multiple continuous 
biomarkers of atherosclerosis as the outcomes of interest. Using the same analysis strategy as Specific 
Aim 1, linear mixed models will be used for each of these atherosclerosis biomarkers as functions of 
treatment group status, treatment order, clinically important covariates, and any significant baseline 
factors. Model fit and assumptions will again be checked via standard diagnostic plots and VIF.  
 
To inform future trials, we will summarize differences in outcome measures from the beginning to end 
of the washout period, and compared to baseline, with mean (standard deviation) and median (range). P-
values will be calculated with paired t-tests or Wilcoxon signed-rank tests for non-normal distributions. 
 
 
Sample Size Justification 
We aim to recruit up to 80 subjects to achieve a final sample size of 60 evaluable subjects. For Aim 1, 
the sample size of 60 (30 in initial sildenafil group and 30 in initial placebo group), gives 80% power 
for a relatively small effect size of 0.37 for the change in %BAD in the sildenafil versus placebo periods 
(using a paired t-test, although we will use a linear mixed model for the analysis). Based on previous 
studies in diabetes, with equivalent CV risk, the estimated standard deviation (SD) of %BAD is 
approximately 4. The effect size of 0.37 thus corresponds to a % increase of 1.5%, which is clinically 
meaningful. We will analyze drop-ins, drop-outs, withdrawals, and non-adherences according to 
intention-to-treat principles. 
 
For Aim 2, given that we are using the same analysis strategy as Aim 1, the sample size of 60 (30 in 
each group) again yields 80% power to detect an effect size of 0.37 for the change in a given biomarker. 
The estimated power (in either aim) corresponding to the final mixed model is difficult to estimate more 


 
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specifically since it is unclear how much residual variability will remain after adjusting for other 
covariates, and/or whether a stronger association will be evident after model adjustment. 
 
POTENTIAL PITFALLS AND SOLUTIONS 
15.3.1 
How will we account for the potential variability in results of 
brachial artery FMD measurements? 
A number of factors may potentially influence the results of brachial artery FMD. To account for this, 
subject-specific factors will be minimized by requesting subjects to limit antioxidant vitamin and/or 
antioxidant-rich diet within 72 hours; document use of CV medications (e.g., -blockers, calcium 
channel blockers, NSAIDs, and aspirin); limit tobacco and caffeine use within 12 hours; document the 
phase of menstrual cycle for premenopausal women (since optimum time for FMD studies is days 1-7 of 
menses); abstain from exercise within 12 hours; and be fasting and rested before the FMD study. 
Finally, since we recognize there is diurnal variation in the FMD response, we will attempt to schedule 
each subject’s visits at consistent times of the day. 
15.3.2 
What if study subject recruitment and retention rates are 
slower and/or less than anticipated? 
We will increase advertising efforts and may open the study at other community rheumatology clinics, 
with over 6,000 active RA patients. We may include those on statins, ACE-i or ARB (on stable dose x 
4+ months), and retain subjects with RA medication changes. We will address these factors statistically, 
if needed. 
15.3.3 
How will the effect of comorbidities and RA disease-related 
factors that affect endothelial function be mitigated so as not to 
confound the results of sildenafil’s effect on endothelial 
function? 
A potential confounder is the effect of traditional CVD risk factors (e.g., DM), CV medications, RA 
medications, disease activity and duration on potential change in endothelial function over time. As 
described in Section 4.4, we plan to adjust for these through multivariable linear mixed models. 
Furthermore, subjects who require a new start or change in RA medication or glucocorticoid 
maintenance dose increase to 10 mg/day or greater for 4+ weeks during the trial will be withdrawn from 
the study. Since this is a randomized placebo-controlled study, we anticipate the frequency of these 
potential confounders will be similar between groups. 


 
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15.3.4 
Will potential effects of sildenafil risk un-blinding due to 
altered erectile function or headaches? 
Potential effect on erectile function is unlikely to be recognized by male subjects unless they already 
suffer from ED, in which they will likely already be taking PDE inhibitors and will thus be excluded. 
Further, most RA patients are women. Per Micromedex, headaches were only seen in 21% of ED 
subjects taking the 50 mg daily dose (vs. 7% in placebo). Although these potential side effects may 
unblind subjects, the outcome measures in this study (vascular function and serum biomarkers) are 
unlikely to be affected by subject un-blinding. Different study personnel will collect AE data vs. other 
outcome data, to minimize risk of un-blinding. 
 
 
Interim Analyses 
Potential non-compliance (assessed via pill counts) will be analyzed using intention-to-treat strategy, 
and for missing data, we will conduct a sensitivity analysis to conservatively assess observing how the 
worst outcome (of %BAD) would affect results. The test of a treatment × period interaction is not 
possible in the given cross-over design since it is confounded by the group effect. 
 
We do not anticipate many subjects with RA or CV medication changes, since inclusion criteria state no 
expected therapy changes over next 6 months. Moreover, such changes are unlikely to occur 
systematically more often in the initial sildenafil vs. placebo groups. However, in the event there are 
many with such changes, we will also conduct a secondary sensitivity analysis including them to assure 
this does not affect results. The %BAD was chosen as the primary outcome on which to calculate 
sample sizes based on clinical considerations. Specifically, %BAD has been validated longer and in 
more populations than PAT.  
 
16. 
QUALITY ASSURANCE 
 
Data recording 
All data will be entered into the secure Rheumatic Disease Management System (RDMS), which is a 
Division-wide system for rheumatologic research. A source document checklist will be used at the site 
to identify the source data for all data points collected. 


 
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Archiving 
Documents shall be archived safely and securely in such a way that ensures that they are readily 
available if required, and in compliance with the University of Pittsburgh guidelines.  According to the 
University of Pittsburgh IRB, all study-related documents will be stored for 7 years. The investigator 
site file is not to be destroyed without approval by NIAMS or the Safety Monitor.   
 
Publication Policy 
Following completion of the SEDRA study, the investigators will publish the results of this research in 
scientific journals.  The International Committee of Medical Journal Editors (ICMJE) member journals 
has adopted a trials-registration policy as a condition for publication.  This policy requires that all 
clinical trials be registered in a public trials registry such as ClinicalTrials.gov, which is sponsored by 
the National Library of Medicine.  The SEDRA study is registered with ClinicalTrials.gov, with number 
NCT02908490. 
 
As this is a single-center study, there will be no publications committee.  Authorship determination will 
be made in consultation with the co-investigators of the study.   
 
Publication of the results of this trial will be governed by NIAMS publication policies.  Any 
presentation, abstract, or manuscript will be made available for review by the NIAMS supporters prior 
to its submission. Dr. Liang will maintain control of all SEDRA-generated specimens and will decide on 
the scientific merit of any future sub-studies. They will adhere to the letter and the spirit of the 
prevailing NIH and NIAMS guidelines on the sharing of research resources produced from federally-
funded research. Specifically, any publications will be submitted, as required, to the NIH National 
Library of Medicine PubMed central for archiving upon acceptance for publication. These policy details 
(http://grants.nih.gov/grants/guide/notice-files/NOT-OD-05-022.html) will be adhered to. 
 
Confidentiality / HIPAA 
This is a single-center study, with a relatively small number of subjects.  All personnel involved in this 
study have undergone training and certification on the protection of human subjects, confidentiality, 
HIPAA compliance and research integrity.  This training is conducted regularly by the University of 
Pittsburgh via an internet-based system of education in research.  
 


 
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The only individuals with access to identifiable information and treatment assignment will be the data 
manager and study statistician.  Access to study data will be password protected.  All linkage materials 
are stored separately and maintained in a secure area.   
 
All blood samples will be collected in a de-identified manner using labels generated through the RDMS 
system.  Linkage codes will be maintained by the data manager in the event of emergencies or future 
need, and these will be kept in a locked filing cabinet located in the Division of Rheumatology research 
office. 
 
ETHICAL AND LEGAL CONSIDERATIONS 
 
Ethical and legal conduct of the study 
The procedures set out in this protocol, pertaining to the conduct, evaluation, and documentation of this 
study, are designed to abide by GCP guidelines and under the guiding principles detailed in the 
Declaration of Helsinki.  IRB approval has been obtained.  The investigator may implement a deviation 
from, or a change of, the protocol to eliminate an immediate hazard(s) to the trial subjects without prior 
IRB approval.  As soon as possible, the implemented deviation or change, the reasons for it and if 
appropriate the proposed protocol amendment will then be submitted to the University of Pittsburgh 
IRB.  Any deviations from the protocol will be explained and documented by the investigator.  Protocol 
deviations will also be reported biannually to the Safety Monitor.   
 
Subject information and consent 
The investigator will discuss that written approval of the IRB has been obtained.  Consent forms, 
describing in detail the therapies, procedures, and risks, will be given to the participant, and written 
documentation of informed consent is required prior to starting the study agent(s).  Consent forms will 
be IRB-approved, and the participant will be asked to read and review the document.  Upon reviewing 
the document, the study coordinator will explain the research study to the participant and answer any 
questions that may arise.  The participants will sign the informed consent document prior to any 
procedures being done specifically for the study.  The participants will have sufficient opportunity to 
discuss the study and process the information in the consent process prior to agreeing to participate.  
Only if the subject voluntarily agrees to sign the informed consent form and has done so, may s/he enter 


 
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the study.  Additionally, the PI will personally sign and date the form.  The subject will receive a copy 
of the signed and dated form.  The signed informed consent statement is to remain in the investigator 
site file.  In the event that informed consent is obtained on the date that baseline study procedures are 
performed, the study record or subject´s clinical record must clearly show that informed consent was 
obtained prior to these procedures.