International Sites: CONNECTS Master Protocol for Clinical Trials Targeting Macro-, Micro-immuno-thrombosis, Vascular Hyperinflammation, and Hypercoagulability and Renin-angiotensin-aldosterone System (RAAS) in Hospitalized Patients With COVID-19 (ACTIV-4 Host Tissue)
Phase: PHASE2
Conditions: COVID-19, SARS-CoV2 Infection, Coronavirus Infection
Sponsor: NEAT ID Foundation

 
 
 
 
  Short Title:  Novel Experimental COVID Therapies Affecting Host Response (NECTAR) 
 
  Full Title: CONNECTS Master Protocol for Clinical Trials targeting macro-, micro-immuno-   
thrombosis, vascular hyperinflammation, and hypercoagulability and renin-angiotensin-
aldosterone system (RAAS) in hospitalized patients with COVID-19 (ACTIV-4 Host Tissue) 
 
  NCT number: NCT05593770 
 
  Date: 18 Oct 2022 
 
 
 

 
 
 
 
 
CONNECTS Master Protocol for Clinical Trials targeting macro-, micro-immuno-
thrombosis, vascular hyperinflammation, and hypercoagulability and renin-angiotensin-
aldosterone system (RAAS) in hospitalized patients with COVID-19 (ACTIV-4 Host Tissue) 
 
 
Short Title:  Novel Experimental COVID Therapies Affecting Host Response (NECTAR) 
COVID-19 Inpatient Host Tissue Master Protocol 
 
ClinicalTrials.gov Number: NCT04924660 
 
Supported by: NHLBI-CONNECTS 
 
Version Number: 4.0 
 
2022.10.18 
 
 
 
Study Chair 
 
 
Principal Investigator, 
Clinical Coordinating Center  
 
Sean P. Collins, MD, MSc 
Email: sean.collins@vumc.org  
 
Wesley H. Self, MD, MPH 
Email: wesley.self@vumc.org  
Principal Investigator,  
Data Coordinating Center 
Matthew S. Shotwell, PhD 
Email: matt.shotwell@vumc.org   
Trial Biostatisticians 
Christopher J. Lindsell, PhD 
Email: chris.lindsell@vumc.org   
 
James Troendle, PhD 
NHLBI 
Email: James.troendle@nih.gov  
Medical Monitor 
Matthew Semler, MD, MSc 
Email: matthew.w.semler@vumc.org  
NHLBI Representative 
Yves Rosenberg, MD 
Email: rosenbey@nhlbi.nih.gov  
Ex-U.S. Sponsor 
NEAT-ID 
IND 
154000 
ClinicalTrials.gov Identifier 
NCT04924660 
NECTAR EudraCT 
2022-000715-31 
sIRB study number 
210982 

 
 
Table of Contents 
 
1 
List of Abbreviations ............................................................................................................... vii 
2 
Master Protocol Summary ....................................................................................................... 9 
3 
Introduction, Background Information and Scientific Rationale ............................................ 12 
3.1 
Background Information, Significance and Relevant Literature .................................... 12 
3.2 
Relevance of host tissue pathway(s) to COVID-19 ....................................................... 13 
3.3 
Rationale for evaluating host tissue therapies in a single platform among patients who 
are hospitalized with COVID-19 ................................................................................................ 13 
3.4 
Potential Risks & Benefits .............................................................................................. 14 
4 
Study Objectives and Purpose .............................................................................................. 14 
4.1 
Study Objectives ............................................................................................................ 15 
4.2 
Study Hypothesis ........................................................................................................... 15 
5 
Study Design and Outcomes................................................................................................. 15 
5.1 
Overall Study Design ..................................................................................................... 15 
5.2 
Randomization ............................................................................................................... 15 
5.3 
Study Outcomes ............................................................................................................. 15 
5.3.1 
Primary Study Outcome .......................................................................................... 15 
5.3.2 
Secondary Outcomes ............................................................................................. 16 
5.3.3 
Exploratory Outcomes ............................................................................................ 17 
5.3.4 
Safety Outcomes (systematically collected during index hospitalization) ............. 17 
6 
Study population and enrollment ........................................................................................... 17 
6.1 
Inclusion criteria ............................................................................................................. 17 
6.2 
Exclusion criteria ............................................................................................................ 18 
6.3 
Justification of exclusion criteria .................................................................................... 18 
6.4 
Special screening procedures........................................................................................ 19 
6.5 
Assessment of eligibility and exclusion tracking ............................................................ 19 
6.6 
Process of obtaining informed consent ......................................................................... 19 
6.6.1 
Paper-based approach ........................................................................................... 19 
6.6.2 
Electronic/e-consent approach for US sites only ................................................... 20 
6.6.3 
Attestation of informed consent .............................................................................. 21 
6.7 
Randomization and blinding ........................................................................................... 21 
6.7.1 
Emergency Unblinding ............................................................................................ 22 
6.8 
Vulnerable Subjects ....................................................................................................... 22 
6.9 
Strategies for Recruitment and Retention ..................................................................... 23 
6.10 
Duration of Study Participation ...................................................................................... 23 
6.11 
Participant Withdrawal or Termination ........................................................................... 23 
6.11.1 
Reasons for Withdrawal or Termination ................................................................. 23 
6.11.2 
Premature Termination or Suspension ................................................................... 23 
7 
Study Procedures and Schedule ........................................................................................... 24 
7.1 
Study interventions ......................................................................................................... 24 
7.2 
Expedited Critical and Major Event Reporting ............................................................... 24 
7.3 
Data and Safety Monitoring Plan ................................................................................... 24 

 
 
7.4 
Biological specimens ...................................................................................................... 25 
7.5 
Shared placebo group dose, duration, and route of administration .............................. 25 
7.6 
Co-Interventions and Co-enrollment .............................................................................. 25 
7.7 
On study monitoring ....................................................................................................... 26 
7.7.1 
Laboratory evaluations ........................................................................................... 26 
7.7.2 
Clinical evaluations ................................................................................................. 26 
7.7.3 
Criteria for stopping drug ........................................................................................ 26 
7.7.4 
Plan for drug shortages .......................................................................................... 27 
7.7.5 
Baseline variable collection .................................................................................... 27 
7.7.6 
Assessments between hospital presentation and hospital discharge ................... 28 
7.7.7 
Assessments following hospital discharge ............................................................. 28 
8 
Statistical Considerations ...................................................................................................... 30 
8.1 
Statistical and Analytical Plans ...................................................................................... 30 
8.2 
Analysis Datasets ........................................................................................................... 30 
8.3 
Statistical Modeling ........................................................................................................ 30 
8.4 
Loss to Follow-up, Censoring, and Intercurrent Events ................................................ 31 
8.5 
Model Prior and Bayesian Computation ........................................................................ 31 
8.6 
Analysis of Primary Outcome ......................................................................................... 31 
8.6.1 
Primary Analysis ..................................................................................................... 31 
8.6.2 
Planned Interim and Final Analyses, Early Stopping, and Type-I Error Control ... 32 
8.6.3 
Supplementary Efficacy Estimands ........................................................................ 32 
8.6.4 
Sensitivity and Supplementary Analyses ............................................................... 32 
8.6.5 
Sample Size and Decision Thresholds ................................................................... 34 
8.7 
Analysis of Secondary Outcomes .................................................................................. 36 
8.8 
Analysis of Safety Outcomes ......................................................................................... 37 
8.9 
Adherence and Retention Analyses .............................................................................. 37 
8.10 
Baseline Descriptive Statistics ....................................................................................... 37 
8.11 
Exploratory Analyses ..................................................................................................... 37 
9 
Measures to Minimize Bias ................................................................................................... 37 
9.1 
Enrollment/Randomization/Blinding ............................................................................... 37 
10 Source Documents and Access to Source Data/Documents ............................................... 37 
11 Quality Assurance and Quality Control ................................................................................. 38 
12 Ethics/Protection of Human Subjects .................................................................................... 38 
12.1 
Ethical Standard ............................................................................................................. 38 
12.2 
IRB/Ethics Committee/Competent Authority.................................................................. 38 
12.3 
Posting of Clinical Trial Consent Form .......................................................................... 38 
12.4 
Participant and Data Confidentiality ............................................................................... 38 
12.5 
Certificate of Confidentiality ........................................................................................... 39 
13 Adverse events ...................................................................................................................... 39 
13.1 
Defining adverse events................................................................................................. 41 
13.2 
Protocol-specified exempt serious events (PSESEs) ................................................... 42 
13.3 
Monitoring and recording adverse events ..................................................................... 44 
13.4 
Reporting adverse events .............................................................................................. 45 
13.4.1 
Adverse Events that Qualify for Expedited Reporting ............................................ 45 

 
 
13.4.2 
Grade 3 and 4 Clinical Adverse Events.................................................................. 46 
13.4.3 
Pregnancy ............................................................................................................... 46 
13.5 
Medical Monitor .............................................................................................................. 48 
14 Risk Assessment ................................................................................................................... 48 
14.1 
Potential risks of other study procedures ...................................................................... 48 
14.2 
Minimization of risk ......................................................................................................... 48 
14.3 
Potential benefit .............................................................................................................. 49 
14.4 
Risk in relation to anticipated benefit ............................................................................. 49 
15 Data and Safety Monitoring Board (DSMB) .......................................................................... 49 
16 Data Handling and Record Keeping...................................................................................... 49 
16.1 
Data Collection and Management Responsibilities ....................................................... 49 
16.2 
Study Records Retention ............................................................................................... 50 
16.3 
Protocol Deviations ........................................................................................................ 50 
16.4 
21 CFR Part 11 Compliance .......................................................................................... 50 
16.4.1 
Record locking ........................................................................................................ 50 
16.4.2 
eConsent ................................................................................................................. 50 
17 End of Trial ............................................................................................................................ 51 
18 Study Finances ...................................................................................................................... 51 
18.1 
Funding Source .............................................................................................................. 51 
18.2 
Costs to the Participant .................................................................................................. 51 
19 Appendix A: Primary study outcomes ................................................................................... 52 
19.1 
Approach to ascertainment and verification of outcomes ............................................. 52 
19.2 
Primary outcome: Oxygen free days ............................................................................. 52 
19.3 
Definitions ....................................................................................................................... 54 
19.3.1 
ICU Level of care .................................................................................................... 54 
19.3.2 
Myocardial injury ..................................................................................................... 54 
19.3.3 
Acute Kidney Injury ................................................................................................. 54 
19.3.4 
Disseminated Intravascular Coagulation (DIC) (Overt) – DIC score ≥ 5 ............... 54 
19.3.5 
ISTH Defined Major Bleeding ................................................................................. 55 
20 Appendix B: Data and Safety Monitoring Plan ...................................................................... 56 
20.1 
Overview ......................................................................................................................... 56 
21 Appendix C: Minimum Biological Specimen collection ......................................................... 57 
22 Appendix D: Arm 3: Fostamatinib ......................................................................................... 58 
22.1 
Description of active therapy .......................................................................................... 58 
22.2 
Rationale for evaluating Fostamatinib ........................................................................... 58 
22.3 
Fostamatinib dose, duration, and route of administration ............................................. 59 
22.4 
Placebo ........................................................................................................................... 60 
22.5 
Fostamatinib-specific safety considerations and potential medication interactions ..... 60 
22.6 
Fostamatinib Arm-Specific Exclusion Criteria................................................................ 61 
22.7 
Dose Modification Considerations and Medication Interactions ................................... 61 
22.8 
Fostamatinib Arm Logistics ............................................................................................ 65 
23 Appendix E. Non-NAT Tests Deemed with Equivalent Specificity to NAT by the Protocol 
Team ............................................................................................................................................. 67 

 
 
24 References ............................................................................................................................ 68 
 
List of Tables 
Table 1.  
Schedule of Events ............................................................................................... 29 
Table 2.  
Overview of Safety Data Collection .................................................................... 40 
Table 3.  
WHO COVID-19 Clinical Status Scale and its use for enrollment eligibility 
and   calculation of oxygen free days (OFD) ........................................................................... 53 
Table 4.  
Descriptions of OFD Data .................................................................................... 54 
 
 
List of Figures 
Figure 1.  
Adverse Event and Clinical Outcome Assessment, Recording, and Reporting
 
47 
Figure 2.  
Spleen tyrosine kinase inhibition in COVID-19 (Strich, Generated using    
Biorender) 59 
Figure 3.  
Schematic overview of blood pressure considerations and procedures    
performed for patients still on study drug at the time of hospital discharge ..................... 62 

 
 
 
1 
List of Abbreviations 
 
AE 
Adverse Event/Adverse Experience 
AESI 
Adverse Event of Special Interest 
ARDS 
Acute Respiratory Distress Syndrome 
CA 
Competent Authority 
CFR 
Code of Federal Regulations 
CHF 
Congestive Heart Failure 
CrCl 
Creatinine Clearance 
COVID-19 
Coronavirus Disease 
CRA 
Clinical Research Associate 
CRF 
Case Report Form 
CSOC 
Clinical Study Oversight Committee 
DCC 
Data Coordinating Center 
DHHS 
Department of Health and Human Services 
DIC 
Disseminated Intravascular Coagulation  
DSMB 
Data and Safety Monitoring Board 
ECMO 
Extracorporeal Membrane Oxygenation 
eGFR 
Estimated Glomerular Filtration Rate 
ESRD 
End-stage renal disease 
FDA 
Food and Drug Administration 
FFR 
Federal Financial Report 
FWA 
Federal Wide Assurance 
GCP 
Good Clinical Practice 
GDPR 
General Data Protection Regulations 
GI 
Gastrointestinal  
HFNO 
High-flow Nasal Oxygen (≥30L/min) 
HIPAA 
Health Insurance Portability and Accountability Act 
ICF 
Informed Consent Form 
ICH 
International Conference on Harmonization 
ICMJE 
International Committee of Medical Journal Editors 
IEC 
Independent Ethics Committee 
IRB 
Institutional Review Board 
ISM 
Independent Safety Monitor 
ISTH 
International Society on Thrombosis and Hemostasis 
ITT 
Intent to Treat 
LAR 
Legally Authorized Representative 

 
 
LOS 
Length of Stay 
MOP 
Manual of Procedures 
N 
Number (typically refers to participants) 
NETs 
Neutrophil extracellular traps 
NIH 
National Institutes of Health 
NIV 
Non-Invasive Ventilation 
NYULH 
New York University Langone Health 
OFD 
Oxygen Free Days 
OHRP 
Office for Human Research Protections 
OHSR 
Office of Human Participants Research 
OSFD 
Organ Support Free Days 
PI 
Principal Investigator 
PRBC 
Packed Red Blood Cells 
PSESEs 
Protocol-specified exempt serious events 
PTT 
Partial Thromboplastin Time 
QA 
Quality Assurance 
QC 
Quality Control 
RRT 
Renal Replacement Therapy 
SARS-CoV-2 
Severe Acute Respiratory Syndrome- Coronavirus- 2  
SAE 
Serious Adverse Event/Serious Adverse Experience 
SUSAR 
Suspected Unexpected Serious Adverse Reactions 
SOP 
Standard Operating Procedure 
US 
United States 
VTE 
Venous Thromboembolism 
WHO 
World Health Organization 
WOCBP 
Women of Childbearing Potential  
 
 

Study number: 210982 
 
 
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ACTIV-4 Host Tissue  
Protocol Version: 4.0 dated 2022.10.18.   
 
 
2 
Master Protocol Summary 
Title 
Master Protocol for Clinical Trials targeting host tissue and the renin-
angiotensin-aldosterone system (RAAS) in hospitalized patients with COVID-
19 
Short Title 
Novel Experimental COVID Therapies Affecting Host Response (NECTAR) 
Brief Summary 
This Master Protocol describes the general design features of a platform trial 
evaluating therapies targeting the host response to COVID-19 in hospitalized 
patients. The Master Protocol provides the background and overarching 
approach to all trials to be conducted on this platform. This includes a 
rationale for the choice of primary outcome, inclusion and exclusion criteria, 
randomization and blinding, interim and final analyses, sample size 
considerations, safety reporting, and data collection. In addition, the Master 
Protocol describes general principles for trial operations and oversight. 
Appendices to the Master Protocol provide agent-specific details, including 
treatment dose, route and frequency, safety information, and any agent- 
specific considerations related to drug starting/stopping, inclusion and 
exclusion criteria and blinding procedures.  
Objectives 
The overarching goal of the Master Protocol is to find effective strategies for 
inpatient management of patients with COVID-19. Therapeutic goals for 
patients hospitalized for COVID-19 include hastening recovery and 
preventing progression to critical illness, multiorgan failure, or death. Our 
objective is to determine whether modulating the host tissue response 
improves clinical outcomes among patients with COVID-19. 
 
Potential agent(s) to investigate on this platform include, but are not limited 
to, TXA127, TRV027, and Fostamatinib. These agents all impact the host 
tissue response in COVID-19 via a number of unique mechanisms including 
potential beneficial effects on the RAAS system and formation of neutrophil 
extracellular traps (NETs).  We will evaluate the efficacy of these agents’ 
ability to impact the host tissue response and improve outcomes in patients 
hospitalized with COVID-19.  
Methodology 
This platform will be a randomized, placebo-controlled trial of agents 
targeting the host response in COVID-19 in hospitalized patients. The Master 
Protocol is designed to be flexible in the number of study arms, the use of a 
single placebo group, and the stopping and adding of new therapies. 

Study number: 210982 
 
 
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Outcomes 
Primary Outcome:  
Oxygen free days through day 28. This is defined as days alive and without 
supplemental oxygen use during the first 28 days following randomization. 
Patients who die prior to day 28 are assigned -1 oxygen free days.   
 
Secondary outcomes: 
• In hospital mortality 
• Proportion of patients alive and oxygen free at days 14 and 28 
• Proportion of patients with new invasive mechanical ventilation at day 28 
• 28-day mortality 
• 60-day mortality  
• 90-day mortality    
• WHO 8-point ordinal scale at 14, 28, and 60 days 
▪ 
1: Ambulatory – Not hospitalized and no limitation of activities 
▪ 
2: Ambulatory – Not hospitalized with limitation of activities or 
home oxygen use 
▪ 
3: Hospitalized Mild Disease – Hospitalized, no oxygen 
therapy 
▪ 
4: Hospitalized Mild Disease – Hospitalized, oxygen by mask 
or nasal prongs 
▪ 
5: Hospitalized Severe Disease – Non-invasive ventilation or 
high-flow nasal cannula 
▪ 
6: Hospitalized Severe Disease –Invasive mechanical 
ventilation 
▪ 
7: Hospitalized Severe Disease – Invasive mechanical 
ventilation plus additional organ support with- vasopressors, 
RRT, or ECMO 
▪ 
8: Dead 
• Support-free days through Day 28, including: 
o Hospital-free days 
o Ventilator-free days  
o Respiratory failure free days 
 
Exploratory Outcomes 
• Renal outcomes: acute kidney Injury defined as > KDIGO Stage 2 and 
changes in serum creatinine and estimated Glomerular Filtration Rate 
• Myocardial injury as measured by changes in troponin before, during and 
after therapy during hospitalization (when possible, at participating U.S. 
sites)   
• RAAS pathway mechanistic biomarkers (AngII, Ang(1-7), ACE and ACE2) 
(when possible and applicable, at participating U.S. sites)  
• Trajectories of biomarkers related to COVID-19 (when possible, at 
participating U.S. sites) 
• Changes in NT-proBNP before, during and after therapy during 
hospitalization (when possible, at participating U.S. sites) 
 
 
 

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Protocol Version: 4.0 dated 2022.10.18.   
 
 
Safety outcomes (systematically collected during index 
hospitalization): 
• Hypotension as defined by low arterial blood pressure leading to either [1] 
initiation or increase in vasopressor therapy, [2] administration of a fluid 
bolus of 500 ml or more, or [3] modification of the dose or discontinuation 
of the study drug. 
• Allergic reaction, including angioedema and rash  
• Incident renal replacement therapy during hospitalization  
Study Duration 
Multiple arms can actively enroll concurrently for an anticipated 15 months. 
Duration of 
Participant 
follow-up 
Duration of hospitalization with post-discharge follow-up for up to 90 days 
after randomization. (Specific eligibility criteria are in the main protocol text) 
Population 
Patients hospitalized for COVID-19 with laboratory confirmed SARS-CoV-2 
infection on oxygen therapy.   
Study Sites 
Sites affiliated with NHLBI-CONNECTS Network of Networks and other 
networks and sites with previous clinical trial experience. Selected sites will 
be sufficiently equipped and experienced to safely enroll and follow patients, 
and to produce accurate data. The number of enrolling sites will be informed 
by the number of hospitalized patients with COVID-19 at active sites, the 
sample size required, and projected patient accrual. 
Planned 
Maximum 
Number of 
Subjects 
We expect the maximum sample size to be about 300 per interventional 
treatment arm. 
Prior to the first interim analysis, sample size adequacy was re-assessed 
based on the pooled (across all active and placebo arms) distribution of the 
primary outcome. No adjustments to the maximum sample size were made. 
Placebo enrollment beyond 300 participants may be required to ensure there 
are sufficient concurrently randomized and eligibility-matched placebo 
participants for comparison with each active drug arm.  
Description of 
Study Agents 
Specific agents will be described within the agent-specific appendices. The 
therapies relevant to this Master Protocol must have some mechanistic link 
to preventing progression to critical illness, multiorgan failure, or death in 
patients with COVID-19 and related to the host tissue response to COVID-
19. 
Key 
Procedures 
Participants will be recruited in the inpatient setting. They will undergo 
baseline evaluations for eligibility. They will then be randomized, stratified by 
site, and study intervention will begin. Baseline laboratories will be required, 
and biobanking will occur both at randomization, and during the study period. 
The primary outcome will be assessed daily via chart review during 
hospitalization. Patients will undergo additional data collection by telephone, 
mail, in-person visits or electronic (e.g., email, text message) surveys after 
discharge. 

Study number: 210982 
 
 
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Protocol Version: 4.0 dated 2022.10.18.   
 
 
Statistical 
Analysis 
The effect of each study agent on the primary outcome, versus matching 
placebo, will be quantified using the odds ratio to evaluate the odds of 
greater oxygen free days at day 28 (i.e., the primary estimand). Estimation 
and inferences about the primary estimand will be made using proportional 
odds logistic regression methods. For each study agent, the comparison 
group will consist of all concurrently randomized placebo participants 
meeting the inclusion and exclusion criteria for that agent.  
For each arm, we will use pre-planned interim analyses at fixed recruitment 
intervals to consider ending enrollment early due to strong evidence of 
inferiority. Early stopping and final analysis thresholds will be selected to 
ensure a type-I error probability of 2.5% (one-sided), separately for each 
study agent.  
We will use a modified intention to treat (mITT) approach for primary 
analyses. All available data on participants who were eligible, randomized, 
and received at least some study drug will be used to compare each 
treatment versus control, regardless of post-randomization adherence to 
study protocols. The intercurrent event of death will be coded as a special 
value in the primary outcome (i.e., composite strategy). Censoring in the 
primary outcome will be modeled using likelihood methods. No other 
intercurrent events will affect the primary outcome (i.e., treatment policy 
strategy). We will monitor closely for patients who are randomized who do 
not receive study drug to ensure our preplanned sample size targets for the 
mITT group are met.            
 
3 
Introduction, Background Information and Scientific Rationale 
3.1 Background Information, Significance and Relevant Literature 
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus 
disease 2019 (COVID-19), has resulted in a global pandemic. The clinical spectrum of COVID-19 
infection is broad, encompassing asymptomatic infection, mild upper respiratory tract illness, and 
severe viral pneumonia with respiratory failure and death. Between 13 and 40% of patients become 
hospitalized,1,2 up to 30% of those hospitalized require admission for intensive care, and there is a 
13% inpatient mortality rate.3,4 The reasons for hospitalization include respiratory support, as well 
as support for failure of other organs, including the heart and kidneys. The risk of thrombotic 
complications is increased, even when compared to other viral respiratory illnesses, such as 
influenza.5 While 82% of hospitalized patients with COVID-19 are ultimately discharged alive,6 
median length of stay is 10-13 days.7 Clinical trials in COVID-19 inpatients are needed to find better 
strategies to prevent or treat progression to critical illness, multiorgan failure, or death. 
Early work in treating COVID-19 has focused on preventing worsening of the initial clinical 
presentation to prevent hospitalization and disease progression to organ failure and death. Studies 
conducted under this Master Protocol are expected to extend our knowledge of how to manage 
patients who are hospitalized for COVID-19 illness.   
This protocol intends to define effective therapeutic regimens in a randomized trial of patients 
hospitalized with COVID-19. The primary outcome is oxygen free days through day 28. 

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3.2 Relevance of host tissue pathway(s) to COVID-19 
Most adults with SARS-CoV-2 infection recover after a brief illness with fever, cough, and fatigue or 
similar symptoms. Current therapies are limited in the subset of patients who progress to 
hypoxemic respiratory failure and acute respiratory distress syndrome (ARDS).8–10 The SARS-CoV-
2 virus enters pulmonary and myocardial cells by the binding of the spike viral protein to the 
Angiotensin-Converting Enzyme 2 (ACE2) receptor, a key actuator in the renin-angiotensin-
aldosterone system (RAAS). Thus, in COVID-19, RAAS has been directly implicated in the 
pathogenesis of ARDS as part of the host tissue response. ACE2 catalyzes the conversion of 
Angiotensin II (AngII) to Ang(1-7). When ACE2 is not present AngII remains at increased levels 
stimulating vasoconstriction, the production of inflammatory cytokines, and pulmonary fibrosis.11 
Even before COVID-19, ACE2 was found to be protective in preclinical models of acute lung injury 
and ARDS. Mice deficient in ACE2 develop acute lung injury following a challenge with a variety of 
insults,12,13 which improves on repletion with recombinant ACE2.14  
3.3 Rationale for evaluating host tissue therapies in a single platform among patients who 
are hospitalized with COVID-19 
The importance of the host tissue response is important to consider in patients hospitalized with 
COVID-19. ACE/Ang II signaling in human disease is suggested by increased levels of ACE and 
Ang II in ARDS and sepsis patients.15–18 Patients with the D allele for the ACE gene have higher 
ACE and Ang II levels in tissue and serum19 and these patients are at higher risk of death from 
ARDS in multiple large cohorts.19–21 Restoration of ACE2 through the administration of recombinant 
ACE2 in a phase II trial of ARDS in humans (n=44) appeared to safely reduce AngII levels and 
increase Ang(1-7) levels without causing significant hemodynamic changes.22 Further, up to 20% of 
patients with COVID-19 develop myocardial injury, which has been independently associated with 
increased arrhythmias, shock and mortality.23–25 ACE2 receptors are present in cardiac myocytes 
and fibroblasts and the endothelium of coronary arteries, and the ACE2 receptor has been 
implicated as a potential mediator of cardiac injury in COVID-19.26 Thrombotic events are a known 
complication in patients hospitalized with COVID-19. In vitro evidence suggests, R406, the active 
component of fostamatinib, can inhibit the Fc-mediated release of proinflammatory cytokines by 
macrophages and platelet-mediated thrombosis provoked by SARS-CoV-2 specific spike 
antigen/antibody complexes. Furthermore, R406 also has been shown to inhibit the release of 
neutrophil extracellular traps from neutrophils stimulated with plasma from patients with COVID-19. 
Taken together, it is hypothesized that fostamatinib will decrease the inflammatory milieu generated 
through Fc-activation, ultimately resulting in decreasing immunothrombosis. Preventing 
immunothrombosis in the pulmonary vasculature could mitigate lung injury and hasten recovery 
from COVID-19.   
Recent large-scale cohort studies, however, have not found an association between current use of 
RAAS inhibitors and either increased risk of contracting COVID-19 infection or increased risk of 
severe disease from COVID-19.27,28 Two randomized trials in patients hospitalized with COVID-19 
who were already taking RAAS inhibitors found no benefit of stopping RAAS inhibitors when 
compared to continuing them (BRACE CORONA, REPLACE COVID).29–31  Thus, mechanistic 
pathophysiology and preliminary data in ARDS provide a compelling rationale for studying the effect 
of agents targeting the RAAS system using a RAAS platform as we propose.  
There is strong a rationale for considering multiple host tissue agents on this platform due to 
complementary but distinct mechanisms of action. TRV027 and Ang (1-7) both work to restore 
AngII balance by working downstream of the ACE2 receptor via different mechanisms of improving 
the Ang(1-7) to AngII ratio. (Figure 1). Recent data from two Phase II trials suggested that 
fostamatinib may have substantial impact on outcomes in patients hospitalized with COVID-19, 

Study number: 210982 
 
 
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ACTIV-4 Host Tissue  
Protocol Version: 4.0 dated 2022.10.18.   
 
 
providing compelling rationale for including this agent on our platform. A recent placebo-controlled 
randomized phase 2 study in hospitalized adults with Covid-19 (NCT04579393) suggested 
fostamatinib in addition to usual care was safe and did not result in more serious adverse events 
(10.5% in the fostamatinib group vs. 22% in the placebo group). Additionally, multiple secondary 
efficacy endpoints showed trends favoring the patients receiving fostamatinib, including 28-day 
mortality, days free of oxygen, and recovery as measured on the 8-point ordinal scale at day 15.  
 
Figure 1. Adapted from Alhenc-Gelas and Drueke 2020; The physiological steps of the generation of 
angiotensin II and angiotensin 1-7 and their actions on specific receptors are shown. The interaction of 
TRV027, and TXA127 at the specific points in the pathway is also displayed. Angiotensin II is 
generated from angiotensinogen by the actions of renin and subsequently anchored to ACE in the cell 
membrane. ACE2, another transmembrane enzyme, removes the carboxyterminal amino acid of 
angiotensin II, thereby inactivating angiotensin II but generating angiotensin 1-7 with biological activity 
distinct from angiotensin II. Angiotensin 1-7 activates the Mas receptor. 
3.4 Potential Risks & Benefits 
Participating in this Master Protocol includes risks related to the treatment, as well as risks related 
to privacy and confidentiality. Benefits include the potential for benefit of the therapeutic strategy, 
increased attention to the participant’s treatments and clinical course when compared with usual 
care, and the global societal benefit of contributing knowledge about COVID-19 treatments and 
pathophysiology. See sections 12 and 13 and agent-specific Appendices for details. 
4 
Study Objectives and Purpose 
The overarching objective of this platform is to iteratively test treatment strategies targeting the host 
tissue response for improving clinical outcomes among adults hospitalized with COVID-19. 

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Treatment strategies will be added to the current best practice and tested against best practice plus 
placebo. Best practice may itself be updated as therapies become available or are shown to be 
effective (or ineffective).  
4.1 Study Objectives 
Our objective is to determine the impact of modulating the host tissue response, including 
counterbalancing RAAS activity, on mortality and outcomes related to ARDS. A further objective is 
to determine which of the different RAAS agents’ targets (AT1r biased agonist, Ang[1-7] infusion) 
and associated mechanisms of action, when added to current best practice and compared to 
current best practice plus placebo, result in an effective therapeutic approach to the RAAS system 
in patients infected with SARS-CoV-2. 
4.2 Study Hypothesis 
We hypothesize the administration of Ang (1-7), TRV027, or fostamatinib (all dosed individually, no 
combinations) will improve clinical outcomes and will result in improvement in oxygen-free days 
through day 28.  
5 
Study Design and Outcomes 
5.1 Overall Study Design 
This Master Protocol describes an overarching approach to studies of blinded, placebo-controlled 
therapeutic approaches of host-tissue targeted therapies in hospitalized COVID-19 patients. The 
Master Protocol is designed so the platform can be flexible in the number of study arms, the use of 
a single placebo group, and the stopping and adding of new therapies, while using a common 
approach to design and implementation.  
5.2 Randomization 
Randomization assignments are at the participant level and treatments are assigned at 
randomization. Randomization will be implemented using permuted blocks and stratified by site and 
eligibility group. Stratification ensures balance across the active and pooled placebo groups at 
regular enrollment intervals within each stratum, thus mitigating the impact of stratum (i.e., site) 
heterogeneity on assessments of treatment effect. Allocation will be equally distributed across arms 
for which the participant is eligible. 
5.3 Study Outcomes 
5.3.1 Primary Study Outcome 
The primary outcome for this platform is oxygen free days (OFD) at day 28. It is designed to assess 
lung function as determined by freedom from oxygen therapy for the first 28 days following 
randomization. This is an important patient-centric outcome reflective of recovery from SARS-CoV-2 
infection. Additional rationale for the primary outcome is explained in detail in Appendix A: Primary 
study outcomes. OFD is a clinically relevant, longitudinal measure of lung function and mortality 
assessed at 28 days after randomization. Liberation from oxygen is an important patient-centric 
outcome and freedom from oxygen dependency is a primary goal for patients during both 
hospitalization and the early post-discharge period. OFD will be calculated using principles developed 
during the past 20 years for other free-day clinical trial outcomes, including ventilator free days,32,33 
organ support free days,34 and hospital free days.35 The concept of time to liberation from oxygen 
therapy, and the related outcome of time to recovery, has been extensively used in COVID-19 trials 
evaluating in-hospital therapies.36,37  For example, the primary outcome for the first trial on the 
Adaptive COVID-19 Treatment Trial platform (ACTT-1)38 was time to recovery during the first 28 days 

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after randomization, defined as time between randomization and the earlier of hospital discharge or 
discontinuation of oxygen therapy and other in-hospital therapies for COVID-19. Oxygen free days 
was selected over time to recovery, as defined in ACTT-1, as the primary outcome for our proposal 
for two reasons: (1) to capture home oxygen use as part of the primary outcome; and (2) to 
incorporate the competing risk of death into the primary outcome using the same methodology 
commonly used for other outcomes evaluating duration of organ support, such as ventilator free days.     
 
OFD will be calculated as the number of calendar days during the first 28 days after randomization 
during which the patient was alive and not receiving new supplemental oxygen therapy.39 Patients 
will be considered to be receiving supplemental oxygen therapy when they are receiving any of the 
following: supplemental oxygen by nasal cannula, supplemental oxygen by face mask, high flow 
nasal cannula (HFNC), non-invasive ventilation (NIV), invasive mechanical ventilation (IMV), or 
extracorporeal membrane oxygenation (ECMO). The day of randomization is denoted as Day 0. 
Starting with calendar day 1 (the day after randomization) and continuing for 28 days, study 
personnel will document whether the patient received oxygen therapy on each day for any duration 
of time. While the patient is in the hospital, the highest level of respiratory support received during 
each calendar day will be documented according to the 8-category WHO COVID-19 clinical status 
scale. Categories 4, 5, 6, and 7 indicate in-hospital oxygen use.  
 
Use of supplemental oxygen at home after discharge will be assessed via telephone follow-up calls 
and text/email responses to the participant or surrogates. Patients who chronically used 
supplemental oxygen prior to their COVID-19 illness will be considered oxygen free when they 
return to the same level of oxygen support, they had been using prior to COVID-19 illness. For 
example, a patient who chronically used supplemental oxygen at 4 liters per minute via nasal 
cannula before COVID-19 and who was intubated for acute management of COVID-19 would be 
considered oxygen free for calculation of the primary outcome when he/she returned to oxygen 
support via nasal cannula at 4 liters per minute or less.  
 
The primary outcome, OFD, will be calculated as 28 minus the number of days with oxygen use 
during the first 28 days after randomization. OFD will be coded as -1 for patients who died before 
study day 28. Hence, the range for OFD is from -1 to 28 days. The first day of follow-up is the day 
after randomization, so 28 OFDs are the maximum possible days (Appendix A: Primary study 
outcomes). 
 
5.3.2 Secondary Outcomes 
• 
Alive and oxygen free at days 14 and 28 
• 
Alive and respiratory failure-free at days 14 and 28 
• 
Alive and free of new invasive mechanical ventilation at 14 and 28 days 
• 
In-hospital, 28-day, 60-day and 90-day mortality 
• 
WHO 8-point ordinal scale at 14, 28 and 60 days 
▪ 
1: Ambulatory – Not hospitalized, no limitation of activities 
▪ 
2: Ambulatory – Not hospitalized with limitation of activities or home 
oxygen therapy 
▪ 
3: Hospitalized Mild Disease – Hospitalized, no oxygen therapy 
▪ 
4: Hospitalized Mild Disease – Oxygen by mask or nasal prongs 
▪ 
5: Hospitalized Severe Disease – Non-invasive ventilation of high-flow 
oxygen 
▪ 
6: Hospitalized Severe Disease –Invasive mechanical ventilation 
▪ 
7: Hospitalized Severe Disease – Invasive mechanical ventilation plus 

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additional organ support with-vasopressors, RRT, or ECMO 
▪ 
8: Dead 
• 
Support-free days to Day 28, including: 
▪ 
Hospital-free days 
▪ 
Respiratory failure-free days 
▪ 
Ventilator-free days  
 
Alive and respiratory failure-free at day 28, the WHO 8-point ordinal scale at day 28, and mortality 
at day 28 are key secondary outcomes that will be treated as a family for testing purposes, even 
though the studies will not be adequately powered to detect anything but a very strong treatment 
effect on these outcomes. A supplementary analysis to assess the evidence that treatment lowers 
the risk of death in a way that is consistent with its effect on nonfatal outcomes will be performed. A 
respiratory failure-free day is defined as a day alive without the use of HFNC, NIV, IMV, or ECMO. 
Participants that are alive but not hospitalized are considered free of respiratory failure. 
5.3.3 Exploratory Outcomes 
Exploratory outcomes will include the following (further defined in Appendix C: Minimum Biological 
Specimen collection): 
• 
Myocardial injury described by changes in troponin before, during and after therapy during 
hospitalization (when possible, at participating U.S. sites).  
• 
Myocardial function described by changes in NT-proBNP before, during and after therapy 
during hospitalization (when possible, at participating U.S. sites).   
• 
RAAS mechanistic biomarkers (AngII, Ang(1-7), ACE and ACE2) before, during and after 
therapy during hospitalization (measured in samples from a subset of participants, when 
possible and applicable, at participating U.S. sites).  
• 
Renal outcomes: acute kidney injury (following KDIGO) defined as > KDIGO Stage 2 and 
changes in serum creatinine and estimated Filtration Rate during hospitalization  
• 
Trajectories of biomarkers related to COVID-19 during hospitalization (when possible, at 
participating U.S. sites).  
 
Exploratory outcomes may be collected at just a subset of sites. 
5.3.4 Safety Outcomes (systematically collected during index hospitalization) 
Safety outcomes will be measured to reflect the expected adverse consequences of therapeutic 
strategies. 
• 
Hypotension as defined by low arterial blood pressure leading to either [1] initiation or 
increase in vasopressor therapy, [2] administration of a fluid bolus of 500 ml or more, or [3] 
modification of the dose or discontinuation of the study drug.   
• 
Allergic reaction, including rash and angioedema 
• 
Incident renal replacement therapy during hospitalization  
 
6 
Study population and enrollment 
A broad population of adults hospitalized with COVID-19 will be enrolled on this platform without 
exclusions based on age, sex, race, ethnicity, severity of disease or preferred language. Exclusion 
criteria are related to safety. Eligibility criteria must be fulfilled at the time of randomization. 
6.1 Inclusion criteria 
1. 
Hospitalized for COVID-19 

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2. 
≥18 years of age 
3. 
SARS-CoV-2 infection, documented by: 
a) 
a nucleic acid test (NAT) or equivalent testing within 3 days prior to 
randomization OR  
b) 
documented by NAT or equivalent testing more than 3 days prior to 
randomization AND progressive disease suggestive of ongoing SARS-CoV-2 
infection per the responsible investigator (For non-NAT tests, only those 
deemed with equivalent specificity to NAT by the protocol team will be 
allowed. A central list of allowed non-NAT tests is maintained in Appendix E. 
Non-NAT Tests Deemed with Equivalent Specificity to NAT by the Protocol 
Team).  
4. 
Hypoxemia, defined as SpO2 <92% on room air, new receipt of supplemental 
oxygen to maintain SpO2 ≥92%, or increased supplemental oxygen to maintain 
SpO2 ≥92% for a patient on chronic oxygen therapy 
5. 
Symptoms or signs of acute COVID-19, defined as one or more of the following: 
a) 
cough 
b) 
reported or documented body temperature of 100.4o F or greater  
c) 
shortness of breath 
d) 
chest pain 
e) 
infiltrates on chest imaging (x-ray, CT scan, lung ultrasound) 
6.2 Exclusion criteria 
1. Onset of COVID-19 symptoms fulfilling inclusion criterion #5 >14 days prior to 
randomization 
2. Hospitalized with hypoxemia (as defined in inclusion #4) for >72 hours prior to 
randomization (the 72-hour window for randomization begins when the patient first 
meets the hypoxemia inclusion criteria after hospital admission)  
3. Pregnancy 
4. Breastfeeding 
5. Prisoners  
6. End-stage renal disease (ESRD) on dialysis  
7. Patient undergoing comfort care measures only such that treatment focuses on end-of-
life symptom management over prolongation of life. 
8. The treating clinician expects inability to participate in study procedures or participation 
would not be in the best interests of the patient 
9. Known allergy/hypersensitivity to IMP or its excipients 
6.3 Justification of exclusion criteria 
The study medications’ impact on breastfeeding and breastmilk is unknown, and we therefore 
exclude breastfeeding. We aim to study the impact of early interventions in the hospitalized setting 
and thus exclude those people who have prolonged symptoms or have been hospitalized greater 
than 72 hours prior to randomization. A patient is considered to have been hospitalized for > 72 
hours prior to randomization if the presentation that initiated the current inpatient admission began 
more than 72 hours before randomization, regardless of the initial location of care (e.g., current 
hospital or transferring hospital) or level of care (e.g., emergency department, hospital ward, 
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6.4 Special screening procedures 
The site investigator or delegate will screen for hospitalized patients with laboratory confirmed 
COVID-19 (that is, a positive laboratory test for SARS-CoV-2) or a pending SARS-CoV-2 test. 
Treating clinicians will also be instructed to contact the site investigator or delegate for patients with 
a high clinical suspicion of COVID-19 prior to confirmatory testing. 
6.5 Assessment of eligibility and exclusion tracking 
For patients who appear to meet inclusion criteria during pre-screening, an electronic pre-screening 
form will be completed to determine eligibility and track exclusions. The electronic pre-screening 
form will be accessed and stored in the electronic pre-screening database. At the time of entry into 
the pre-screening database, the patient will be assigned a pre-screening number.  
If a patient appears to meet all eligibility criteria, the site investigator or delegate will approach the 
treating clinician to ask permission to approach the patient or Legally Authorized Representative 
(LAR) to confirm eligibility, discuss potential study recruitment, and proceed with informed consent.   
For excluded patients located in the United States, including refusal by the treating clinician or 
patient/surrogate, a small number of de-identified pre-screening variables will be collected including 
month and year the patient met pre-screening criteria, age, sex, ethnicity, and reason(s) the patient 
was excluded. For patients located outside of the United States, no personal information will be 
collected prior to consent, nor stored in the pre-screening database. For the safety of research 
personnel and conservation of personal protective equipment (PPE), these encounters may occur 
via telephone or videophone.  
6.6 Process of obtaining informed consent 
Informed consent is a process initiated prior to the individual’s agreeing to participate in the study 
and continues throughout the individual’s study participation. Informed consent should follow both 
local institutional policy and national regulatory guidance including following institutional COVID 
policy to protect study staff. Informed consent will be obtained from the patient or from a surrogate 
decision maker if the patient lacks decision-making capacity.    
In some instances, bringing a paper consent form and pen to the bedside of a patient with known or 
suspected COVID-19 and then taking these out of the room would violate infection control principles 
and policies.  Given the infectious risk from COVID-19 and potential shortages of PPE, there is a 
moral and practical imperative to minimize face-to-face contact between patients and non-clinical 
personnel. The current pandemic also presents unique challenges to obtaining consent from a 
participant’s LAR. To minimize infectious risk, many institutions are not allowing visitors to enter the 
hospital. Furthermore, the LAR is likely to have been exposed to the patient and may therefore be 
under self-quarantine at the time of the informed consent discussion. 
Therefore, in addition to the traditional approach of an in-person consent discussion and signed 
paper informed consent document, we will allow use of “no-touch” consent procedures for this trial.  
Below, we outline three examples of no-touch consent procedures that may be used: (a) a paper-
based approach; (b) an electronic/e-consent approach; and (c) attestation of informed consent.   
6.6.1 Paper-based approach 
1. The informed consent document is delivered to the patient or LAR. 
a. If the patient or LAR is on-site, the informed consent document may be delivered to the 
patient or LAR either by research staff or by clinical staff. 
b. If the LAR is off-site, the informed consent document may be emailed, faxed, or otherwise 
electronically transferred to the LAR (method dictated by institutional policy). 

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2. Research staff discuss the informed consent document with the patient or LAR either in-person 
or by telephone or videophone. This step confirms subject/LAR identity. 
3. If the patient or LAR decides to consent to participate, the patient or LAR signs the paper copy of 
the informed consent document. 
4. A photograph is taken of the signature page by the patient or LAR (or research staff if onsite with 
patient/LAR) of the informed consent document and uploaded into the electronic database (e.g., REDCap). 
Non-US sites will upload consent images into a local database. 
a. If using the patient’s device (such as a patient’s personal cellular phone), a survey link can 
be sent to their device to allow direct upload of the image into the electronic database (e.g., 
REDCap). 
b. If using a staff device, it must be approved to store PHI by the local institution. In that case, 
research personnel can take a photograph of the signature page of the informed consent 
document either directly or through the window or glass door leading into the patient’s room.  
The photograph can then be uploaded into the electronic database.  If a staff device is taken 
into the patient’s room to take a photograph it must be able to be disinfected according to 
local institutional practices.  
5. Research staff and the witness provide signatures within the electronic database (e.g., REDCap) 
confirming their participation in the informed consent process. 
6. The patient or LAR retains the paper consent document. The image of the signature page may 
be printed and bundled with a copy of the blank informed consent document for research records. 
6.6.2 Electronic/e-consent approach for US sites only 
1. The electronic informed consent document is opened on a research device or a link for the 
electronic informed consent document is sent to the patient’s or LAR’s device. 
2. Research staff discuss the informed consent document with the patient or LAR either in person 
or by telephone or videophone. This step confirms subject/LAR identity. 
3. If the patient or LAR decides to consent to participate, the patient or LAR signs the electronic 
informed consent document. This signature may be either: 
a. an actual signature (often tracing a finger on the screen) OR 
b. a username and password specific to the individual signing 
4. Research staff and the witness, provide signatures within the electronic database (e.g., REDCap) 
confirming their participation in the informed consent process. 
5. The image of the signature page may be printed and bundled with a copy of the blank informed 
consent document for research records. 
 
If a hospital device is provided to facilitate electronic or paper-based consent, that device will be 
disinfected according to institutional protocols and removed by research staff or clinical staff during 
the next entry into the patient’s room. 
This approach complies with relevant regulations and sub-regulator guidance at 45 CFR 46.117, 45 
CFR 164.512, 21 CFR 11 Subpart C (11.100–11.300), https://www.hhs.gov/ohrp/regulations-and-
policy/guidance/use-electronic-informed-consent-questions-and-answers/index.html  , 
https://www.fda.gov/regulatory-information/search-fda-guidance-documents/informed-consent . 
The information for the informed consent discussion will be provided in an informed consent 
document (or electronic equivalent), that has been approved by the sIRB and in a language 
comprehensible to the potential participant, using an interpreter if necessary. The information 
presented in the consent form and by the research staff will detail the nature of the trial and what is 
expected of participants, including any potential risks or benefits of taking part. It will be clearly 

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stated that the participant is free to withdraw from the trial at any time for any reason without 
prejudice to future care, and with no obligation to give the reason for withdrawal. Where a patient 
does not speak English, a short-form consent and qualified interpreter will be employed, using 
similar “no-touch” principles.  Use of an interpreter and the interpreter’s identity will be documented 
on the electronic consent. 
6.6.3 Attestation of informed consent 
If none of the options outlined above (traditional signature and storage of a paper consent form, 
electronic photographs of a signed consent page, or e-consent) are available, study personnel may 
attest to completion of the informed consent process using the procedures outlined below.  
Importantly, the process of informed consent using this attestation option should not change 
compared with the traditional method of obtaining informed consent for trial participation except for 
the method of documenting the consent process in the research record. Rather than storing a paper 
document with the participant’s signature, a member of the research team and an impartial witness 
will attest to completion of the informed consent process and that the participant signed the 
informed consent document. This option of attestation of informed consent is not available when 
obtaining consent through a LAR.   
Procedures for attestation of informed consent: 
1. An unsigned paper consent form is provided to the patient by a heath care worker or study member. 
2. The study member obtaining consent arranges an in-person meeting or three-way call or video 
conference with himself/herself, the patient, and an impartial witness. If desired and feasible, 
additional people requested by the patient (e.g., next of kin) may also join this discussion. 
3. A study member reviews consent and answers questions in the presence of the impartial witness. 
4. Patient signs the paper informed consent document while the witness is listening on the phone or 
directly observing. 
5. Patient provides verbal confirmation that he/she would like to participate in the trial, and he/she 
has signed and dated the informed consent document. This signed informed consent document 
stays with the patient due to the risk of spreading the virus.   
6. Study member and witness attest that other techniques for documenting informed consent were 
not available for this participant and that the participant provided written informed consent for trial 
participation by signing a paper informed consent document. An attestation form with signatures 
from the study member and witness will be saved as evidence of the informed consent process. A 
signature from the participant will not be saved in the research record.   
6.7 Randomization and blinding 
Randomization assignments are performed for patients at enrollment. Randomization will be 
implemented using a permuted block method and stratified by site and eligibility group. The eligibility 
group for each participant is the set of study arms for which the participant is eligible. Participants are 
not eligible for arms that have not begun or have ceased enrollment. Stratification by site ensures 
balance across the active and pooled placebo groups at regular enrollment intervals at each site, thus 
mitigating the impact of site heterogeneity on assessments of treatment effect. Eligible participants will 
be randomized through a central electronic system. On entry to the study and confirmation of eligibility 
to at least one active drug arm, the participant will be randomized m:1 to either the active (will receive 
one of the study drugs) or placebo (will not receive one of the study drugs) condition. Here, m is the 
number of open study arms for which the patient is eligible. If the patient is eligible for only one agent, 
or only one study arm is open, then allocation is 1:1. For two agents, it is 2:1, for three it is 3:1 and so 
on. Once participants are assigned as active or placebo, the participant will then be randomized with 
equal probability to receive one of the active drugs for which they are eligible, or a corresponding 
placebo (matched by route and frequency of administration). For the purposes of interim and final 

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analyses, the route and frequency of placebo will be ignored, and all placebo participants will be pooled 
together as a single group. In comparing an active drug versus placebo, only those placebo participants 
that were eligible for the active drug will be considered. Randomization will be implemented using 
permuted blocks, stratified by site and eligibility group. A block size multiplier, either 1 or 2, will be 
selected uniformly at random for each block. Blocking ensures balance within strata across each active 
and corresponding pooled placebo group and across study arms at the end of each block. Placebos 
that match the route (e.g., intravenous vs oral) and frequency of the corresponding active agent further 
ensure patient and assessor blinding. Which study arm the participant enters will be known to the 
research sites and the participants, but assignment to active versus placebo will be blinded. The 
randomized assignment, concealed from the research team, will be transmitted to the site pharmacy 
who will provide study medication. The participant, treating clinicians, study personnel (other than the 
investigational pharmacist, medical monitor, and the unblinded statistician who prepares closed session 
DSMB reports), and outcome assessors will all remain blinded to group assignment until after the 
database is locked and blinded analysis is completed. The medical monitor will remain blinded except 
as required for individual patient safety. In cases in which unblinding of the medical monitor is required 
for individual patient safety, assessment of adverse events by the medical monitor will be performed 
prior to unblinding.  After assessing adverse events, the medical monitor will communicate directly with 
Coordinating Center to receive the unblinded group assignment needed to inform individual patient 
safety. The medical monitor will not discuss any unblinded information with blinded trial personnel. If an 
additional adverse event occurs for a patient for whom the medical monitor has been unblinded for 
individual patient safety, an alternate medical monitor will be appointed to review the adverse event and 
determine seriousness, severity, and relatedness.  
 
6.7.1 Emergency Unblinding 
The investigator has the sole responsibility to break the blind in the case of a patient medical 
emergency. If the investigator believes unblinding the treatment assignment for a participant is 
needed for the safe medical treatment of that participant, unblinding will be discussed and 
information requested from the Vanderbilt Coordinating Center (VCC). For unblinding requests, 
including emergency unblinding, please contact the VCC as well as your local CRA. 
 
Unblinding will only occur if determined to be required for patient safety or treatment after 
discussion between the site investigator and the Medical Monitor. Stopping of study drug 
without unblinding may be deemed to be sufficient in some cases. If a site investigator 
determines that unblinding may be warranted, the following steps should occur:  
1. 
Site investigator determines unblinding may be warranted. 
2. 
Site investigator contacts the VCC by phone to request unblinding. The 
unblinding request will be transmitted via the VCC to the Medical Monitor. 
3. 
Medical Monitor will review the unblinding request and discuss with the site 
investigator regarding the need for unblinding. 
4. 
If unblinding is determined to be warranted, Medical Monitor documents and 
certifies need for unblinding in REDCap eCRF, accesses the randomized group 
assignment, and transmits this information to the site investigator. 
5.        At sites outside the United States, the site investigator may unblind prior to 
contacting the medical monitor. 
6.8 Vulnerable Subjects 
Prisoners will not be enrolled due to difficulty obtaining follow-up for the primary outcome after hospital 
discharge. Children will not be enrolled because children typically do not display symptoms associated with 

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COVID-19 and therefore are less likely to be hospitalized (the setting in which this study will be conducted). 
Pregnant women will not be enrolled due to potential teratogenicity of the investigational agents.  
This trial may include participants who have no capacity to consent but for whom a LAR may 
provide consent. Patients without the capacity to consent for themselves will have a potential for 
direct benefit by participating in the trial. Capacity assessment will be conducted by the treating 
physician based on the standard clinical assessment of capacity and communicated to the study 
team. When a participant lacks capacity at enrollment, consent will be obtained from the LAR 
before any study-related procedures begin. Participants’ capacity will be monitored throughout the 
study by working with the treatment team. If the participant regains the capacity to consent, they will 
be approached for reconsent, including being informed of their participation in the study and having 
an opportunity to withdraw from further participation in the study. Consent from a LAR for persons 
lacking decision-making capacity will conform to local legal requirements. 
6.9 Strategies for Recruitment and Retention 
Listings of patients admitted to the participating sites with COVID-19 may be reviewed for eligibility 
by the study team, to identify and recruit potential participants, until study enrollment goals have 
been met. Participant recruitment will be by direct communication between the inpatient care team 
and the study team, allowing the treating team the option to advise of any conditions that would 
preclude any individual patient being approached. 
6.10 Duration of Study Participation 
Duration of study participation is for 90 days from randomization. 
6.11 Participant Withdrawal or Termination 
6.11.1 Reasons for Withdrawal or Termination 
Participants are free to withdraw from participation in the study at any time upon request. If the 
nature of treatment makes immediate withdrawal unsafe, withdrawal may be tapered.  
An investigator may terminate participation in the study if any situation occurs such that continued 
participation in the study would not be in the best interest of the participant or the integrity of the study.  
Discontinuation of a study agent, regardless of the reason, e.g., patient or physician request, or 
adverse event, does not constitute study withdrawal. Patient data will still be collected as planned 
and analyzed as intention to treat unless the participant withdraws consent for continued follow-up. 
6.11.2 Premature Termination or Suspension  
The platform, or any arm of the study, may be temporarily suspended or prematurely terminated if 
there is sufficient reasonable cause. Circumstances outside of interim analyses that may warrant 
termination or suspension include, but are not limited to: 
• 
Determination of unexpected, significant, or unacceptable risk to participants in a strategy, 
such as excess mortality or serious adverse treatment effects 
• 
Insufficient compliance to the protocol requirements 
• 
Insufficient accrual in a study arm  
 
If the platform stops for safety, noncompliance, or data quality, it may resume once such concerns 
about safety, protocol compliance, or data quality are addressed and satisfy the requirements of 
appropriate oversight bodies including but not limited to the sIRB, the DSMB, and the FDA. 

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Decisions to stop a study arm or the platform based on the accruing data are not considered 
premature termination or suspension. They will be guided by the decision thresholds described in 
the statistical analysis plan and augmented by details in relevant Appendices. Such decisions will 
generally be weighed by the DSMB. Reasons for stopping based upon the data will include safety 
(DSMB review of AEs) or demonstration of inferiority.  
 
7 
Study Procedures and Schedule 
7.1 Study interventions 
Study agents are described in the agent-specific appendices.  
A summary of the trial’s schedule of events is listed in Section 7.7 and included in  
Event 
Baseline & 
Randomization Day 
0 
Day 1 – Day 28 
Discharge 
Day 
60  
Day 90 
Visit Windows 
 
Day 7 and 14 + 1 Day 
Day 21 + 2 Days 
Day 28 + 5 Days 
 
+ 10 
Days 
 
+ 14 
Days  
 
Confirm eligibility 
X 
 
 
 
 
Obtain informed consent 
X 
 
 
 
 
Screen by reviewing medical history 
and EMR 
X 
 
 
 
 
Pregnancy test, 
X 
 
 
 
 
Randomization  
X 
 
 
 
 
Concomitant medications 
X 
X7 
 
 
 
Record results of SOC laboratory 
assessments  
X4 
X  
 
 
 
Study-specific blood draws 
• 
CBC with diff and LFTs in 
fostamatinib arm 
X4 
X 
 
 
 
Study-specific biological specimen 
collection 
• 
EDTA plasma 
• 
Serum 
X4 
X 
 
 
 
Respiratory failure free days, 
oxygen free days and hospital free 
days   
X4 
X  
X 
 
 
WHO Ordinal Scale  
X 
X 
 
X 
 
Mortality 
X 
X 
X 
X 
X 
Sequential Organ Failure 
Assessment score  
X 
 
 
 
 
Initiate treatment 
X 
 
 
 
 
Continue study medication 
treatment 
 
X 
 
 
 
Adverse event monitoring  
X 
X7 
 
X 
 

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Table 1 (Following section 7.7). 
Timing of study procedures is based on the day and time of randomization, which sets Day 0 and 
Time 0. The primary outcome will be assessed on Study Day 28 or at the time of death.  
Study medications will be administered by clinical or research personnel while the patient is 
hospitalized. The first dose of study medication will be administered within 6 hours of 
randomization. In the hospital, medication delivery after the first dose will correspond to the timing 
of other scheduled medication delivery for the hospital/unit when possible. If the patient is 
discharged, the study medication will be stopped unless the oral study medication is planned to be 
continued in the outpatient setting.  
, On each day the participant is hospitalized and scheduled to receive study drug, study personnel will 
review patient records to confirm administration of study drug and document the number and reason 
for any missed doses. Research personnel will also assess patients daily during hospitalization for up 
to 28 days post-randomization. If the participant is discharged before the full 28-day period, data will 
be collected according to a set schedule (Day 1, 3, 7, 14, 21, and 28 post-randomization) beginning at 
the next corresponding day post-discharge. This includes data regarding oral study medication 
administration in those subjects who are randomized to arms with oral study medication. These 
assessments may be completed by phone or electronically (email, text, or survey link) if the patient 
has been discharged from the hospital. Patients in the fostamatinib arm could require an in-person 
visit depending on their clinical profile at the time of discharge. This is further defined in Appendix D: 
Arm 3: Fostamatinib. At day 60 we will collect AEs, the WHO 8-point ordinal scale and assess vital 
status. A final contact will be made at day 90 to assess vital status.  
7.2 Expedited Critical and Major Event Reporting 
All efficacy and safety outcome events will be assessed and documented in the patients’ study 
records as outlined in section 13. Events meeting the DSMB-specified expedited reporting criteria 
must be reported immediately to the coordinating center and no later than 24 hours from knowledge 
of occurrence. Standing SOPs applicable to all sub studies will guide the reporting of adverse 
events to ensure they are assessed quickly and are submitted to the DSMB, IRB(s), sponsor and 
other groups as needed (e.g., FDA). All participating sites will also be expected to comply with any 
local requirements for reporting. 
7.3 Data and Safety Monitoring Plan 
[The data and safety monitoring plan (DSMP) is described briefly in Appendix B: Data and Safety 
Monitoring Plan and in detail in a separate DSMP document.]  
7.4 Biological specimens 
Participants in this Master Protocol are expected to contribute biological specimens for discovery. 
The biological specimens to be collected, including collection times, processing requirements, and 
storage and shipping, are described in Appendix C: Minimum Biological Specimen collection, and 
any additions to this minimum specimen collection will be described in relevant appendices. 
7.5 Shared placebo group dose, duration, and route of administration 
Each active agent will have a matching placebo. Placebo formulations are described in the 
appendices for each agent.  
Record discharge disposition 
 
 
X 
 
 

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7.6 Co-Interventions and Co-enrollment 
This trial will control the use of study medications (active and control) during the treatment window. 
Study arm specific medication contraindications are explained in detail in the study arm specific 
Appendices. All other treatment decisions will be made by treating clinicians without influence from 
the protocol. The decision to administer antiviral medications, including remdesivir or convalescent 
plasma, or immunomodulating medications, including corticosteroids, will be made by treating 
clinicians and will be recorded in the case report form. We expect usual care to evolve as the study 
progresses, and this will be defined by the most recent available evidence and local drug supply.  
Sponsor and/or protocol leadership may, based upon convincing new evidence, act in the interest 
of participant protection, and in avoidance of confounding, to exclude/dis-allow use of any specific 
concomitant therapy found to be reasonably contraindicated for a well-defined portion of the study 
population. Such a determination may be made, communicated, and implemented by a Protocol 
Clarification Memo until it is reasonable to amend the protocol for other reasons.   
Participants will be asked at screening to agree to refrain from participation in other clinical trials 
until at least the assessment at Day 90 except for trials comparing different approaches for 
implementing SOC interventions or those approved by trial leadership.  
Co-enrollment in other trials will only be allowed in the US where a co-enrolling trial has been approved 
by trial leadership. We will consider several principles when considering co-enrollment in the Master 
Protocol. 
1) This will only apply to clinical trials where there is open label enrollment to facilitate interim and 
final analyses of data for this trial, including treatment interactions, and the attribution of causality of 
serious adverse events and unanticipated problems. 
2) Co-enrollment will not be permitted with trials involving medications with contraindications to co-
administration with any study drug for which the participant is eligible. This review and consideration 
will be similar to consideration of concomitant medications. This assessment will occur prior to 
randomization in the ACTIV 4 Host Tissue platform. This ensures there are no specific drug-drug 
interactions in the event the patient is receiving active therapy in the assigned arm.  
3) Trials involving medications impacting the RAAS pathway will not be considered.  
4) Study procedures for the co-enrolling trial will be considered secondary to the procedures for the 
RAAS MP. We will aim to collect the primary and key secondary outcomes for the co-enrolling trial 
but consider the overall participant burden when fulfilling trial procedures for the co-enrolling trial 
such as additional blood draws and participant assessments. 
5) Co-enrollment prior to randomization will be documented. The impact of co-enrollment on the 
effects of active agents versus placebo on the primary outcome (i.e., heterogeneity of treatment 
effect) will be examined as a supplementary analysis.  
We aim to co-enroll with the ACTIV-4a trial only, an open-label randomized trial now studying the 
impact of P2Y12 inhibitors, SGLT2 inhibitors and crizanlizumab on top of usual care. Patients will 
be randomized in ACTIV-4a to one of these medications at a time in an open label fashion. There 
are no drug-drug interactions with agents in our platform. Patients co-enrolled in ACTIV-4 Host 
Tissue and the crizanlizumab domain of ACTIV-4a require 36 hours between administration of 
fostamatinib and the first crizanlizumab co-administration. Patients who receive both an SGLT2 
inhibitor and fostamatinib need to be monitored for volume depletion. SGLT2 inhibitors can cause 
an osmotic diuresis and patients on fostamatinib may develop diarrhea. Based on the anticipated 
overlap in sites, similarity in inclusion and exclusion criteria, and willingness of patients to co-enroll 
in other ACTIV studies, we expect less than 5% of patients will be co-enrolled in ACTIV-4a.   

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7.7 On study monitoring 
All patients will be hospitalized at the time they are enrolled in the study and will therefore receive 
monitoring as a part of routine clinical care, including monitoring by their physicians, nurses, 
respiratory therapists, and ancillary staff. Clinical and laboratory data obtained as part of routine 
clinical monitoring will be collected. Those labs required to evaluate secondary and safety 
outcomes that are not collected as part of usual care will be obtained for the purpose of the study 
protocol as outlined in section 7.7.6. 
7.7.1 Laboratory evaluations 
Routine clinical monitoring will follow laboratory results when measured as part of usual care which 
may include daily complete blood count (CBC), renal function (creatinine/eGFR), electrolytes, D-
dimer, CRP, and measures of coagulation (PT/PTT/INR). In the fostamatinib trial a daily CBC and 
liver function tests will also be performed while in the hospital on study drug.  
7.7.2 Clinical evaluations 
Between randomization and hospital discharge or end of study drug, study personnel will review the 
electronic health record daily for potential medication interactions with the host tissue agents being 
studied (see Appendix D). If a medication considered to be contraindicated with the host tissue 
agent is discovered, treating clinicians will be contacted to discuss if stopping study drug is 
appropriate or if the medication in question can be stopped or substituted. Those medications in the 
fostamatinib arm with absolute contraindications (Appendix D) will be held or study drug stopped. 
When there are relative contraindications treating clinicians will determine whether an alternative 
medication would be appropriate or whether the risk-benefit ratio favors continuing the medication 
with the known potential interaction.  
7.7.3 Criteria for stopping drug 
Criteria for holding/stopping each trial drug are contained in the trial specific appendices (Appendix D).  
 
To delineate reasons for study drug discontinuation, if study drug is discontinued the study team will 
be prompted to indicate why it was discontinued. There will be 3 options to choose from: 
 
1. Logistical - i.e.  loss of IV access, CT scan, transport, etc. – no AE reporting/recording required 
2. Clinical events that did not represent an AE – i.e., Fostamatinib stopped due to starting 
contraindicated medication – no AE reporting/recording  
3. Due to a possible AE or PSESE –study team directed to go to PSESE or AE reporting page 
in electronic data capture form. 
 
7.7.4 Plan for drug shortages 
In the event of a shortage of study drug at a participating trial site, the trial arm will be suspended at 
that site, but the platform trial will continue.   
7.7.5 Baseline variable collection 
Baseline is defined as the patient’s status at randomization.  Physiological measurements and 
laboratory results obtained in the 24 hours prior to randomization may contribute to baseline data. 
The baseline study-specific blood draws may be completed at any time between consent and the 
first dose of study medication. The following information will be obtained to reflect the patient’s 
baseline status:  
1. Confirmation of informed consent for trial participation 
2. Confirmation of inclusion/exclusion eligibility criteria for trial participation  

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3. Confirmation of the participant not being pregnant including a study-dedicated pregnancy 
test for women of childbearing potential (WOCBP).  
a. WOCBP are defined as any female who has experienced menarche, has not 
undergone surgical sterilization (hysterectomy, bilateral salpingectomy, or bilateral 
oophorectomy), and has not experienced menopause  
b. Postmenopausal women, defined as someone who has gone through menopause, 
do not have to take a pregnancy test.  
4. Admission data: date and time of presentation, origin (home, skilled nursing facility, 
rehabilitation/long-term-acute care hospital, nursing home, outside hospital, outside ICU), 
location at enrollment (ED, hospital ward, ICU) 
5. Sociodemographics (such as age, sex, race, ethnicity, height, weight, poverty index) 
6. Study-specific blood draws (AngII, Ang(1-7), ACE and ACE2, NTproBNP and Troponin) as 
indicated for each investigational agent in the Ancillary Biomarker Appendix (Appendix C: 
Minimum Biological Specimen collection). 
7. Comorbidities such as: AIDS, Leukemia, Malignant Lymphoma, Hemiplegia, 
Cerebrovascular Disease, Prior Myocardial Infarction, Congestive Heart Failure, Peripheral 
Vascular Disease, Dementia, COPD, Connective Tissue Disease, Peptic Ulcer Disease, 
History of Hypertension, HIV positive (without AIDS), Alcoholism, Coronary Artery Disease, 
Solid Tumor, Liver Disease, Diabetes Mellitus, Chronic Kidney Disease 
8. Acute signs and symptoms such as: altered mental status, acute hypoxemic respiratory 
failure, liver function tests, renal function, coagulation studies, chest imaging results 
9. Sequential Organ Failure Assessment (SOFA)  
10. Chronic use of medications, such as: corticosteroids, ACE inhibitors, angiotensin receptor 
blockers, non-steroids anti-inflammatory drugs, others  
11. Receipt of antiviral medications between hospital presentation and randomization: 
chloroquine, hydroxychloroquine, remdesivir, lopinavir/ritonavir, others  
12. Receipt of immunomodulators between hospital presentation and randomization: 
corticosteroids, tocilizumab, sarilumab, interferon β, others  
13. Receipt of anticoagulation and anti-platelet agents between hospital presentation and randomization 
14.  COVID-19 vaccination status  
15. Receipt of COVID-19 convalescent plasma between hospital presentation and randomization 
16. Receipt of anti-SARS-CoV-2 monoclonal antibodies between hospitalization and randomization  
17. Receipt of invasive mechanical ventilation, non-invasive ventilation, high-flow nasal cannula, 
vasopressors, and oxygen therapy at randomization 
18. Vital signs  
 
7.7.6 Assessments between hospital presentation and hospital discharge 
1. On days of study medication administration (before study administration in those arms 
where study drug is not an infusion) 
a. Adverse events of any grade severity present prior to the infusion or medication 
administration 
b. Start and stop (or administration time if oral) times of the infusion of the 
investigational agent/placebo- and restart time if medication stopped for hypotension  
c. Starting dose of study medication administration  
d. New adverse events of grade 3-4 severity during and after study medication 
administration   
2. Recording of specifics of study treatment according to assigned arm 
3. Daily laboratory assessments as part of routine clinical care (CBC, BMP, LFTs, PT/PTT/INR, 
D-dimer and CRP).  

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4. Daily vital signs (including blood pressure), secondary outcomes and safety assessments. In 
the fostamatinib arm a daily CBC and liver function tests will also be performed.   
5. Study-specific blood draws (AngII, Ang(1-7), NT-ProBNP and Troponin) as indicated for 
each investigational agent in the Ancillary Biomarker Appendix (Appendix C: Minimum 
Biological Specimen collection). 
6. Targeted concomitant medications administered daily in the hospital including remdesivir, 
Corticosteroids, antiplatelet/anticoagulation, convalescent plasma, monoclonal Ab’s, 
antibacterial agents, antiviral agents against SARS-CoV-2, ACEI’s, ARBs, beta blockers. 
7. Date and time of first receipt of supplemental oxygen, high-flow nasal cannula, non-invasive 
ventilation, invasive mechanical ventilation, vasopressors, and extracorporeal membrane 
oxygenation (if applicable)  
8. Date and time of final receipt of supplemental oxygen, high-flow nasal cannula, non-invasive 
ventilation, invasive mechanical ventilation, vasopressors and extracorporeal membrane 
oxygenation (if applicable) 
9. Pulmonary embolism, systemic arterial thromboembolism, myocardial infarction, or ischemic 
stroke at hospital discharge or 28 days, whichever occurs first 
10. Date and time of first ICU admission 
11. Date and time of final ICU discharge  
12. Data and time of hospital discharge  
 
7.7.7 Assessments following hospital discharge 
Patients will be followed through 90 days following randomization. The following data will be collected: 
1. Number and reason for missed doses of study drug (only for those discharged prior to 
completing study drug if applicable) 
2. Date of death (if applicable) through day 90 
3. ED visits, hospital readmissions, and use of supplemental oxygen, HFNC, NIV, IMV or 
ECMO after hospital discharge through day 60 
4. Safety outcomes (section 5.3.4) after hospital discharge and adverse events as defined in 
the drug specific appendices and section 13 at day 28 and day 60 (or if discharged earlier 
as outlined in section 7.1) 
5. New or worsening symptoms not previously present at day 28 and day 60 (or if discharged 
earlier as outlined in section 7.1) including fever, chills, cough, chest pain, dyspnea, 
headache, sore throat, congestion, runny nose, fatigue, body aches 
 
 
 

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Table 1.  
Schedule of Events 
 
 
1 Perform events daily through day 28 or discharge, whichever occurs first. Only perform if patient is hospitalized.  
2 Perform for all women of childbearing potential. 
3 Perform only if not completed for current admission. 
4 Perform prior to treatment administration 
5 Only in the fostamatinib arm if not performed as part of usual care – performed daily while on study drug as an inpatient. 
A repeat CBC, LFTs and BP check may be necessary depending on values at discharge as indicated in Appendix D: Arm 
3: Fostamatinib. 
6 Coordinate with clinical lab draws when possible- as delineated in Appendix C: Minimum Biological Specimen collection  
7 Collect at Day 1, 3, 7, 14, 21, and 28 post-randomization if patient is discharged before 28 days.  
8 Administration route and timing/frequency is treatment specific 
Event 
Baseline & 
Randomization Day 
0 
Day 1 – Day 281 
Discharge 
Day 
60  
Day 90 
Visit Windows 
 
Day 7 and 14 + 1 Day 
Day 21 + 2 Days 
Day 28 + 5 Days 
 
+ 10 
Days 
 
+ 14 
Days  
 
Confirm eligibility 
X 
 
 
 
 
Obtain informed consent 
X 
 
 
 
 
Screen by reviewing medical history 
and EMR 
X 
 
 
 
 
Pregnancy test2,3 
X 
 
 
 
 
Randomization  
X 
 
 
 
 
Concomitant medications 
X4 
X7 
 
 
 
Record results of SOC laboratory 
assessments  
X4 
X  
 
 
 
Study-specific blood draws5 
• 
CBC with diff and LFTs in 
fostamatinib arm 
X4 
X 
 
 
 
Study-specific biological specimen 
collection6 
• 
EDTA plasma 
• 
Serum 
X4 
X 
 
 
 
Respiratory failure free days, 
oxygen free days and hospital free 
days   
X4 
X  
X7 
 
 
WHO Ordinal Scale  
X 
X 
 
X 
 
Mortality 
X 
X 
X 
X 
X 
Sequential Organ Failure 
Assessment score  
X 
 
 
 
 
Initiate treatment8 
X 
 
 
 
 
Continue study medication 
treatment 
 
X 
 
 
 
Adverse event monitoring  
X 
X7 
 
X 
 
Record discharge disposition 
 
 
X 
 
 

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8 
Statistical Considerations 
This section describes the statistical approach for each comparison of active treatment versus its 
concurrent and eligibility matched placebo comparator group.   
8.1 Statistical and Analytical Plans 
There will be a formal Statistical Analysis Plan (SAP). This SAP will provide detailed descriptions of 
all primary, secondary, and sensitivity analyses, all interim and final decision thresholds, and all 
required documentation to ensure the reproducibility of statistical analyses. The SAP will be 
finalized prior to the first interim analysis for the platform, and arm-specific SAP amendments (if 
required) will occur before the first interim analysis involving that arm. The finalized SAP will take 
precedence and override the statistical considerations described in this section of the master 
protocol (i.e., Statistical Considerations). 
8.2 Analysis Datasets 
All sub studies conducted under this protocol will use a modified intention-to-treat (mITT) approach 
for primary analyses. The mITT analysis dataset (i.e., the “full analysis set”) will include all 
randomized participants according to the treatment assigned at randomization regardless of 
subsequent compliance or protocol violations, with the following exceptions: Participants who do not 
receive study drug will be excluded from the mITT analysis dataset. Those patients who were 
randomized and found to be ineligible will be excluded from the mITT analysis dataset. The safety 
analysis dataset will be produced, which will consist of all participants who received at least one 
dose of study medication grouped by the drug received. No statistical hypothesis tests nor other 
statistical inferences will be made using the safety analysis dataset unless requested by the DSMB. 
Per protocol analyses will not be routinely performed but may be conducted as sensitivity analyses 
to support the mITT analysis. A key monitoring data point is the count of participants who are 
randomized and included in the ITT dataset but have not received study drug. We expect this to be 
less than 5% among participants who have completed the study. If this becomes greater than 5% 
during the trial, study leadership will meet with study teams to explore and mitigate this issue and 
will ensure the number of patients who receive study drug meets the original enrollment goals. We 
will report results for both the mITT (primary) and ITT datasets. 
8.3 Statistical Modeling 
The effect of each study agent versus matching placebo will be quantified using an odds ratio. The 
odds ratio represents the treatment effect on the odds of greater values of the primary outcome 
(i.e., improved lung function through 28 days, as measured by oxygen-free days). Based on the 
behavior of similar outcomes in prior trials,32–36 we anticipate the distribution of the primary outcome 
to be irregular, with peaks around -1 to 0 and between 22 and 28 days. Thus, we will use a flexible 
semi-parametric approach for the primary outcome analysis. Estimation and inferences about the 
odds ratio will be made using Bayesian proportional odds (PO) logistic regression methods.40,41 For 
each study agent, the comparator group will consist of participants concurrently randomized to 
receive placebo who also meet the inclusion and exclusion criteria for that agent. 
The general form of the PO model can be written in terms of the covariates 𝑋 and an outcome 
variable  𝑌, where probabilities of outcome value y or greaterPr(𝑌≥𝑦|𝑋) = expit(α𝑦+ 𝑋β) where 
α𝑦 is the intercept for outcome value y and expit is the logistic (inverse logit) transformation and X 
contains baseline covariates and treatment. β represents the log odds ratio (OR) associated with 

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the effects of covariates and group assignment. Specifically, the odds ratio represents the relative 
effect of treatment versus placebo on the odds Pr(𝑌≥𝑦|𝑋) (1 −Pr(𝑌≥𝑦|𝑋))
⁄
, for any value y. 
8.4 Loss to Follow-up, Censoring, and Intercurrent Events 
Participants who withdraw consent prior to data collection, or for whom there is no partial 
information about the primary outcome, will not be excluded from analysis. We will strive to avoid 
loss to follow-up by making repeated attempts to contact participants or otherwise retrieve 
participant records. If loss-to-follow-up cannot be avoided, and the information needed to compute 
the primary endpoint is partially known (i.e., censored), we will use likelihood-based methods to 
account for this censoring. For example, if a study participant received supplemental oxygen every 
day during a 10-day period after randomization, but is then lost to follow-up, the primary outcome is 
only partially known (i.e., OFDs ≤ 18 in this example). The PO model provides a convenient 
mechanism to account for this and other types of censoring using a likelihood-based approach.42 
For observations that are fully observed, the log likelihood contribution is 𝑙(𝛼, 𝛽;  𝑦, 𝑥) =
log Pr(𝑌= 𝑦|𝑋= 𝑥). For observations that are left censored at 𝑦 (e.g., ≤ 18 OFDs) observations, 
the log likelihood contribution is 𝑙(𝛼, 𝛽;  𝑦, 𝑥) = log Pr(𝑌≤𝑦|𝑋= 𝑥). The latter is conveniently 
computed by substituting 1 −expit(α𝑦+ 𝑥β). Censored observations on the primary outcome due to 
loss of follow-up, including observations that are censored with respect to both oxygen requirement 
and mortality, will be handled using this mechanism. 
 
All primary analyses will be implemented using the mITT analysis dataset as described above (see 
Analysis Datasets). The intercurrent event of death will be coded as a special value in the primary 
outcome (i.e., composite strategy). Censoring in the primary outcome will be modeled using the 
likelihood method described above. No other intercurrent events will affect the primary outcome 
assessment (i.e., treatment policy strategy).43 
8.5 Model Prior and Bayesian Computation 
A flat prior distribution will be used for all PO model parameters. This ensures that the estimate of the 
primary estimand will be free of influence from an informative prior, and the Bayesian estimate will be 
identical to the maximum likelihood estimate. The posterior distribution for the log odds ratio will be 
approximated using the Laplace method.44 Use of a flat prior ensures the Laplace-approximated 
posterior distribution is identical to the asymptotic sampling distribution of the maximum likelihood 
estimate; in both cases a normal distribution centered at the estimate with variance-covariance equal 
to the inverse Hessian of the log likelihood function. All statistical inferences about the odds ratio will 
be made using this method. Statistical uncertainty about supplementary estimands (e.g., treatment 
difference in the median of the primary outcome) will be quantified using the delta method.45 We feel 
there is insufficient information, specific to the study agents and primary outcome, upon which to justify 
a more informative prior. The flat prior approach ensures that Bayesian inferences regarding the 
efficacy of study agents are based exclusively on the data collected in the ACTIV-4 Host Tissue trial.  
8.6 Analysis of Primary Outcome 
8.6.1 Primary Analysis 
The effect of each study agent versus matching placebo will be quantified using an odds ratio, 
which quantifies the treatment effect on the odds of greater values of the primary outcome. 
Estimation and inference about the primary estimand (and supplementary estimands) will be 
implemented using Bayesian PO logistic regression methods, adjusting for the active drug vs 
placebo indicator variable, age group (18-30, 31-65, >65 years), sex at birth, baseline WHO COVID 

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ordinal outcome score at baseline. Evidence for efficacy will be quantified using the posterior 
probability that the active agent versus placebo odds ratio is greater than one (i.e., treatment is 
associated with greater oxygen free days at day 28). This is denoted the “efficacy probability” or 
𝑃(OR > 1|Data), where OR represents the odds ratio, and Data represents the available outcome 
data. The posterior probability for inferiority/harm is defined as 𝑃(OR ≤1|Data). The primary 
analysis will be implemented separately for each study agent, where the matching placebo group 
will consist of concurrently randomized participants meeting the inclusion and exclusion criteria for 
that agent. The primary and supplementary estimands will be presented with 95% credible intervals. 
While we do not anticipate missing covariate data. 
 
8.6.2 Planned Interim and Final Analyses, Early Stopping, and Type-I Error Control 
At the final analysis (only) for each arm, efficacy will be indicated if the posterior probability for 
efficacy exceeds a common threshold. For studies under this master protocol, the efficacy threshold 
will be selected using statistical simulation to ensure a type-I error probability of 2.5% for each study 
agent.  
 
Two planned interim analyses will occur separately for each study arm when the number of 
participants with complete 28-day follow-up (or were deceased, withdrawn, or lost-to-follow-up by 
day 28) reaches 33% and 67% of maximum enrollment for that arm. Interim analyses will be 
executed by unblinded personnel only. Participant records that inform the primary outcome must 
undergo monitoring prior to interim (and final) analysis. At each interim analysis, a study arm may 
be stopped early if there is evidence for inferiority/harm. The trial will be stopped early if the 
posterior probability for inferiority/harm exceeds 0.95.  
 
8.6.3 Supplementary Efficacy Estimands 
The PO model is attractive for the analysis of ordinal and quantitative response variables, such as 
the primary outcome, because they directly model the cumulative distribution function from which 
the mean, median, other percentiles, and cumulative probabilities of the primary outcome, stratified 
by treatment group, are easily derived.46 In addition to the odds ratio, the effects of treatment versus 
placebo will be quantified using the difference in mean, difference in median, and differences in 
clinically relevant proportions associated with the primary outcome (e.g., mortality at day 28: 
Pr(𝑌= −1|𝑋), and oxygen requirement every day until day 28: Pr(𝑌= 0|𝑋)). These important and 
clinically meaningful supplementary estimands will be used to describe and communicate the 
treatment effect. The posterior distribution for each of the supplementary estimands is readily 
computed using standard Bayesian methods. 
 
8.6.4 Sensitivity and Supplementary Analyses 
Sensitivity and supplemental analyses will be implemented at the final analysis. 
 
The proportional odds assumption of the PO model specifies that the effect of treatment on the 
odds that Y ≥ 3 (measured as an odds ratio versus placebo) is the same relative effect as for Y ≥ 4. 
However, even when the PO assumption is strongly violated, the estimated OR remains a simple 
function of the Wilcoxon-Mann-Whitney U-statistic, namely the probability that a randomly chosen 
patient on treatment B has a higher response than a randomly chosen patient on treatment A,47 the 
probability index or concordance probability. Thus, statistical testing based on the odds ratio, as 
estimated using the PO model, are robust to violations of the PO assumption and provide a 
reasonable global assessment of treatment effectiveness. However, derived quantities such as the 
difference in means may be more sensitive to violations of the PO assumption. Deviations from 

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proportional odds will be examined by separately estimating the odds ratio for each possible 
dichotomization (that preserves ordering) of the primary outcome (e.g., alive versus dead at day 28, 
alive and oxygen free for at least 10 days at day 28 versus alive and oxygen free for fewer than 10 
days or dead at day 28, etc.). 
 
Analysis of partially observed or missing outcome data requires assumptions regarding the 
mechanism by which censoring and missing values arise. The likelihood method described above, 
and other similar methods such as multiple imputation assume that missing values occur at random 
(i.e., missing at random or MAR). However, because censored and missing values cannot be 
observed, assumptions about the missingness mechanism are not verifiable. In order to assess the 
sensitivity of study findings to violations of this assumption, we will conduct additional sensitivity 
analyses by reproducing the primary analysis under alternative assumptions regarding the 
mechanism for missing values. Specifically, we will perform sensitivity analyses that vary 
assumptions about the missing outcomes on the two treatment arms separately. These analyses 
will consider the following two scenarios 1) each partially observed primary outcome in the placebo 
group will be assumed to have taken the highest/best possible value, whereas each partially 
observed primary outcome in the intervention group will be assumed to have taken the lowest/worst 
possible value, and 2)  each partially observed primary outcome in the placebo group will be 
assumed to have taken the lowest/worst possible value, whereas each partially observed primary 
outcome in the intervention group will be assumed to have taken the highest/best possible value. 
These analyses will be implemented using the primary analysis methodology, including an 
assessment of hypothesis testing outcomes. 
 
Co-enrollment in other studies testing COVID-19 therapeutics may occur. Co-enrollment may affect 
the treatment effect estimates if there is effect modification associated with co-enrollment. We 
expect co-enrollment to occur in fewer than 5% of patients enrolled in the trial. However, because 
the decision to co-enroll is not affected by the treatment assignment in ACTIV-4 Host Tissue, co-
enrollment will not favor any particular treatment. In addition, due to its rarity, we expect co-
enrollment to have little impact on the estimated treatment effects, even when there is effect 
modification.  
 
Differential treatment effect, also referred to as heterogeneity of treatment effect, refers to 
differences in efficacy as a function of pre-existing patient characteristics such as baseline 
variables. This is often assessed by forming subgroups or using an interaction analysis. 
Supplemental interaction analyses will be implemented to examine the potential for differential 
treatment effect. Differential treatment effect will be examined in strata defined by (but not limited 
to) respiratory support category at enrollment, status of co-enrollment in an open label clinical trial 
of antiplatelet agents (ACTIV-4a), age category, SARS-CoV-2 vaccination status, and passive 
immunity status, co-enrollment in other studies, and concomitant use of study drug and other 
medications during the study drug administration period. These analyses will be implemented using 
a modified version of the primary analysis method, where the treatment effect will be estimated 
separately for each level of the stratification variable. Stratum-specific treatment effect estimates 
will be presented with 95% Bayesian confidence interval. No formal hypothesis testing will be 
implemented for these analyses.  Studies under this master protocol will be sized only for assessing 
efficacy using the primary analysis. Thus, there may be inadequate power to examine differential 
treatment. 
 

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8.6.5 Sample Size and Decision Thresholds 
The maximum number of participants to be enrolled in sub studies under the Master Protocol is 600 
patients per trial, resulting in approximately 300 patients per active treatment arm, and 300 patients 
in the matching placebo arm. The placebo arm will be shared across all active treatment arms. We 
expect control arm participants to continue to accrue for as long as there are additional treatments 
to test and cases to enroll. New arms may be introduced according to scientific and public health 
needs.  
Type-I error and power regarding the analysis of the primary outcome was assessed based on the 
pooled (across all active and placebo arms) distribution of the primary outcome among the first 100 
participants to complete follow-up and monitoring. The efficacy threshold was identified using 
statistical simulation under the null hypothesis to ensure the study operating characteristics achieve 
design specifications. Pooled and blinded summaries of oxygen-free days at day 28 were used to 
approximate the distribution of the oxygen free days in the placebo group. Based on these data, the 
anticipated frequency distribution, mean, and median of oxygen-free days (OFDs) for the placebo 
group, and for the treatment group under hypothetical effect sizes computed using the PO model 
are displayed in the table below. 
 
 
Inferiority 
Superiority 
OFDs / Odds Ratio 
Placebo 
0.67 
0.80 
1.40 
1.45 
1.50 
1.55 
1.60 
1.65 
1.70 
Mean 
8.8 
6.6 
7.5 
10.8 
11.1 
11.3 
11.5 
11.7 
11.9 
12.0 
Median 
0 
0 
0 
6.5 
7.5 
9.0 
10.0 
10.5 
12.5 
14.5 
P(OFDs >= 22) 
0.19 
0.14 
0.16 
0.25 
0.26 
0.26 
0.27 
0.28 
0.29 
0.29 
Proportion: 
 
 
 
 
 
 
 
 
 
 
-1 (death) 
0.235 
0.316 0.279 0.181 0.176 0.171 0.166 0.162 0.158 0.154 
0 
0.296 
0.314 0.309 0.268 0.264 0.261 0.257 0.254 0.251 0.247 
1 
0.006 
0.006 0.006 0.006 0.006 0.006 0.006 0.006 0.006 0.006 
--- 
--- 
--- 
--- 
--- 
--- 
--- 
--- 
--- 
--- 
--- 
27 
0.050 
0.034 0.041 0.069 0.072 0.074 0.076 0.078 0.081 0.083 
28 
0.000 
0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 
 
Based on these data and effect size scenarios, a series of statistical simulations were implemented 
to examine the operating characteristics of the statistical study design described above, including 
the plan for randomization, interim analysis, and final assessments of efficacy using the odds ratio. 
In each simulation, participant age group, sex, and baseline WHO COVID severity score were 
randomly sampled with replacement from the values observed, and their effects on the primary 
outcome were simulated to match the estimated effects of age, sex, and WHO score on the primary 
outcome among the first 100 participants and loss-to-follow-up, partially observed oxygen free days 
were simulated to match the observed frequency of partially observed outcomes, which occurred in 
12% of the first 100 participants. To encode attrition, a subset of the simulated study participants 
was selected at random, each with probability 0.12. The primary outcome for each selected 
participant was encoded as partially observed by assuming that oxygen free days may have taken 
any value between -1 and a randomly sampled value ranging from the simulated oxygen free days 
to 28. For example, if the simulated oxygen free days is 10, then a value between 10 and 28 is 
sampled uniformly at random and this value is treated at the upper limit for the partially observed 
oxygen free days. This pattern of partially observed oxygen free days closely resembles the 
patterns observed among the first 100 participants. All simulation analyses, including those 

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associated with interim and final assessment of efficacy and inferiority were implemented using the 
methods described above for the analysis of the primary outcome. 
Simulation under the null hypothesis was used to select the efficacy threshold for the final analysis 
of the primary outcome. The efficacy threshold was selected to ensure no more than 2.5% type-I 
error. In this simulation, 10000 replicates were used to ensure ~0.31% simulation margin of error in 
estimating the type-I error rate. The efficacy threshold was identified as 0.9760. The efficacy and 
inferiority/harm thresholds will be applied as follows: 
Analysis 
Rule 
Result 
Final analysis (only) 
Efficacy probability > 0.976 
Conclude efficacy 
Each interim and final 
analysis 
Inferiority/harm probability > 0.950 
Stop and conclude  
inferiority/harm 
 
Using the selected efficacy and inferiority/harm thresholds, the results of 10000 simulations under 
the null hypothesis, and 1000 simulations per inferiority/efficacy scenario are summarized in the 
table below. In these simulations, the type-I error probability was 2.47%. The frequency of stopping 
early for inferiority under the null was 8.6%. A maximum sample size of 600 participants per arm 
(including matching placebo) provides greater than 85% power to detect an odds ratio of 1.65, 
corresponding to a 3.1-day difference in mean OFDs, and a 7.8 percentage point reduction in 28-
day mortality. Differences larger than 2 ventilator-free days on average have been considered 
clinically important in prior trials.32–34 Thus, the minimum detectable effect with 85% power (MDE85) 
is an odds ratio of 1.65. The frequency of stopping early for inferiority when there was an effect 
larger than OR=1.40 was <1%. When the simulated treatment was inferior/harmful relative to 
placebo, at OR=0.67, a conclusion of inferiority/harm occurred in 83.3% of simulated trials (39.1%at 
the first interim, 27.9% at the second interim, and 16.3% at the final analysis), and the average 
sample size was 193.9 participants receiving the active drug. 
 
Null 
Inferiority 
Superiority 
OFDs / Odds Ratio 
1.00 
0.67 
0.80 
1.40 
1.45 
1.50 
1.55 
1.60 
1.65 
1.70 
Pr(Efficacy) 
0.025 0.000 
0.001 
0.552 
0.631 
0.705 
0.782 
0.826 
0.856 
0.893 
Pr(Inferiority) 
0.108 0.833 
0.508 
0.003 
0.002 
0.001 
0.000 
0.000 
0.001 
0.000 
Pr(Inconclusive) 
0.867 0.167 
0.491 
0.445 
0.366 
0.294 
0.218 
0.173 
0.143 
0.107 
Average(N) 
286.1 193.9 
242.0 
299.4 
299.8 
299.8 
300.0 
300.0 
299.8 
300.0 
 
In order to characterize the effect of uncertainty in the distribution of the OFD outcome on the type-
1 error probability, simulations under the null hypothesis were twice repeated assuming a “mild” and 
“severe” distribution for the OFD outcome. The mild and severe distributions were selected such 
that the unadjusted mortality rate ranged ± 3% relative to the initial simulation. The results of 1000 
simulations in each of the mild placebo and severe placebo scenarios are summarized in the table 
below. In these simulations, the type-I error probability was 2.5% and 2.3%. 
 
 
Severe 
Mild 
OR = 1.00 
OR = 1.00 
Mortality rate 
0.266 
0.206 
Pr(Efficacy) 
0.023 
0.025 
 

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Severe 
Mild 
OR = 1.00 
OR = 1.00 
Pr(Inferiority) 
0.0.119 
0.117 
Pr(Inconclusive) 
0.858 
0.858 
Average(N) 
284.0 
286.4 
 
Prior to the start of enrollment, initial sample size assessments were based on pooled and blinded 
summaries of OFDs from the PassItOn (convalescent plasma) trial of patients hospitalized for 
COVID-19. The inclusion and exclusion criteria for PassItOn are similar to that for ACTIV 4 Host 
Tissue. In these initial assessments, the estimated MDE85 was OR=1.55. Statistical power was 
subsequently reassessed using OFDs summaries in the first 100 participants enrolled in ACTIV 4 
Host Tissue, which demonstrated a more severe distribution relative to PassItOn participants 
(23.6% vs 17.6% mortality). The estimated MDE85 was OR=1.65 at the time of sample size 
reassessment. However, additional information from blinded summaries of the first 200 enrolled 
participants are consistent with the distribution of OFDs observed in PassItOn (18.6% vs 17.6% 
mortality). After discussion of these findings among the blinded study investigators and study 
sponsor, it was determined that statistical power was sufficient, and no sample size adjustment was 
warranted. 
8.7 Analysis of Secondary Outcomes 
The effect of active agent versus placebo on the odds of binary and ordinal secondary outcomes 
will be quantified using logistic and PO regression methods, respectively, adjusting for patient 
demographic and clinical factors (see Primary Analysis). Time-to-event outcomes will be analyzed 
using Cox proportional hazards methods. To incorporate death as an appropriately unfavorable 
possible outcome, deaths will be treated as censored at the end of the evaluation period for the 
endpoint (e.g., Day 28). Where appropriate, the competing risk of death will be addressed using the 
cause-specific hazards method. The proportion of participants who died at fixed time points (e.g., 
day 28) will be estimated using Kaplan-Meier methods. In order to preserve consistency across the 
primary and secondary analyses, we will uniformly apply a Bayesian approach using flat priors. For 
each key secondary outcome, efficacy testing (one-sided) will be assessed using the odds ratio or 
hazard ratio, by comparing the corresponding posterior probability of efficacy to a threshold. Each 
threshold will be selected using either a simulation-based method, or an approach similar to most 
conventional statistical testing procedures, to ensure each test for efficacy has a type-I error 
probability no more than 2.5%.  Odds ratio, hazard ratio, and differences in proportions (e.g., death 
at 28 days) estimates will be presented with a 95% credible interval.  
 
A gatekeeping/fixed-sequence testing approach will be used to preserve the type-I error rate across 
tests of the primary and secondary outcomes. Specifically, a conclusion of efficacy regarding the 
primary outcome will be required prior to testing the key secondary outcomes. The fixed-sequence 
method will be used to test the following key secondary outcomes in the order given: alive and 
respiratory failure-free at day 28, the WHO 8-point ordinal scale at day 28, and mortality at day 28. 
A one-sided type-I error rate of 2.5% will be used for each test. This approach preserves the 
familywise type-I error rate for the family of primary and key secondary outcomes. Heterogeneity of 
treatment effect may be examined for secondary and safety outcomes, as a function of pre-existing 
patient characteristics and baseline variables. 

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8.8 Analysis of Safety Outcomes 
Monitoring and reporting of safety events will be conducted continuously as described in the Data 
and Safety Monitoring Plan. This section describes the assessment of safety endpoints at the 
interim and final analyses. Agent-specific safety and toxicity endpoints (if any) are detailed in that 
therapy’s appendix. The frequencies of adverse events, mortality, and other safety endpoints, and 
the treatment effect on the odds of these events (i.e., the odds ratio) will be reported with 95% 
credible intervals, using Bayesian ordinal and binary logistic regression methods in a manner 
similar to that described for the analysis of secondary outcomes. 
8.9 Adherence and Retention Analyses 
Receipt of planned therapy will be recorded on case report forms and monitored continuously. 
Should minimum adherence not be achieved routinely, the arm may require modification. 
Adherence, retention, and accrual will be reported to the DSMB and may be considered as reasons 
for premature termination or suspension of arms, or the entire platform.  
8.10 Baseline Descriptive Statistics 
All variables will be summarized using median and other quantiles, mean, and Gini’s mean 
difference (a robust measure of variability defined as the mean absolute difference between any two 
patients’ values). Variable summaries will be presented by treatment group. Because treatments are 
randomized, differences in baseline characteristics will not be formally tested with respect to 
treatment groups. Emphasis is placed on describing the patient sample. In the case that inclusion 
criteria differ across the various treatment arms, treatment specific summaries will be made by 
combining patients enrolled in each specific treatment arm and its matching placebo group. 
8.11 Exploratory Analyses 
Exploratory analyses may proceed as specified within arm-specific SAPs. Exploratory analyses that 
are not specified prior to data collection, such as exploration of the association between novel 
biomarkers and treatment response, are acceptable. In general, the SAP for such exploratory 
analyses should be specified prior to executing the exploratory analysis. 
9 
Measures to Minimize Bias 
9.1 Enrollment/Randomization/Blinding 
All participants meeting eligibility for inclusion will be screened for exclusion criteria. Reasons for 
exclusion will be documented. Monitoring for systematic exclusions will be continuous and failure to 
screen and enroll without bias may result in termination of a site from the trial.  
To prevent bias in allocation of participants to individual sub studies or to arms within sub studies, 
participant eligibility should be confirmed prior to releasing the randomization allocation. 
Randomization will occur at baseline and will generally be equal across all arms for which a patient 
is eligible unless specified in an arm-specific appendix. Randomization will be stratified by study 
site. 
Blinding of patients, providers, and study team members to study arm allocation will be employed to 
reduce bias in conducting study activities and evaluations. Special precautions may be needed to 
blind outcomes assessors if patients or investigators are unblinded to treatment assignment. 
10 Source Documents and Access to Source Data/Documents 
Source documents are original documents, data, or records that are created during a clinical study, 
relating to the medical treatment and the history of the participant, and from which study data are 

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obtained. The purpose of source documents is to document the existence of study participants and 
substantiate the integrity of the study data collected. Any document in which information, an 
observation, or data generated relevant to a study is recorded for the first time is a source document.  
Each study participant will sign a consent form, which includes language on who may access their 
source data and documents used for the study. Locations where study data are generated must 
allow access to source documents as part of clinical study monitoring and oversight. 
11 Quality Assurance and Quality Control 
Quality assurance (QA) is implemented by the study team through a system of best-practice 
standards, reviews, and corrective actions ensuring products and services are of the highest 
achievable quality. The study team and staff members participate in a number of quality activities, 
ensuring the sponsor, OHRP, and FDA research standards are met. QA also encompasses 
independent QA oversight processes verifying the quality of the work through independent reviews, 
qualifications, inspections, and audits, assuring research staff members, contractors, and service 
providers are following the best research and professional practices. 
Quality control (QC) activities include data entry checks in the electronic data capture (EDC) 
system, centralized monitoring, in-person or remote site monitoring, and other activities. To monitor 
studies, clinical monitoring staff review research records and regulatory documents. Reports 
generated from the EDC system may also guide discussions with site research staff.  
12 Ethics/Protection of Human Subjects 
12.1 Ethical Standard 
All studies conducted under this Master Protocol will adhere to the highest ethical standards. The 
trial will be carried out in compliance with the protocol, the ethical principles laid down in the 
Declaration of Helsinki, in accordance with the ICH Harmonized Guideline for Good Clinical 
Practice (GCP), the EU directive 2001/20/EC/EU regulation 536/2014 and other relevant 
regulations. Further, studies will be conducted in full conformity with Regulations for the Protection 
of Human Subjects of Research codified in 45 CFR Part 46, 21 CFR Part 50, 21 CFR Part 56, 
and/or the ICH E6. 
12.2 IRB/Ethics Committee/Competent Authority 
This trial will be initiated only after all required legal documentation has been reviewed and 
approved by the Vanderbilt University Medical Center’s IRB (serving as the single IRB [sIRB])/ 
Independent Ethics Committee (IEC) and competent authority (CA) according to national and 
international regulations. The same applies for the implementation of changes introduced by 
amendments to both the protocol and informed consent form. A determination will be made 
regarding whether previously consented participants need to be re-consented. 
12.3 Posting of Clinical Trial Consent Form 
The informed consent form approved by the sIRB for US sites will be posted on the clinical 
trials.gov website after the clinical trial protocol is finalized and the first patient is enrolled. 
12.4 Participant and Data Confidentiality 
Participant confidentiality and privacy is strictly held in trust by the participating investigators, their 
staff, and the sponsor(s). This confidentiality is extended to cover testing of biological samples and 
genetic tests in addition to the clinical information relating to participants.  

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All investigators and trial site staff will comply with the requirements of the current General Data 
Protection Regulations (GDPR) where applicable with regards to the collection, storage, processing 
and disclosure of personal information and will uphold the applicable local regulations core principles. 
Personal information collected will be kept secure and data access will be limited to the minimum 
number of individuals necessary for quality control, audit, and analysis. 
The study monitor, other authorized representatives of the sponsor, representatives of the sIRB, and 
regulatory agencies may inspect all documents and records required to be maintained by the 
investigator, including but not limited to, medical records (office, clinic, or hospital) and pharmacy 
records for the participants in this study. The clinical study site will permit access to such records. In 
the case that a pharmaceutical company holds an IND for an agent contributing to this study and on 
which this study relies, the pharmaceutical company supplying study product may also inspect study 
records. 
The study participant’s research information will be securely stored at each clinical site and 
transmitted to and securely stored at the Data Coordinating Center. The study data entry and study 
management systems used by clinical sites and by the Data Coordinating Center research staff will 
be secure and password protected. Wherever feasible, data will be identified by a Participant ID 
number, and not by any direct identifiers. At the end of the study, all records at a clinical site will 
continue to be kept in a secure location for as long a period as dictated by the reviewing sIRB/IECs, 
Institutional policies, country-specific/local regulations, or sponsor requirements. On completion of 
the study, de-identified data may be made available to others outside the study team.  
12.5 Certificate of Confidentiality 
To further protect the privacy of study participants, a Certificate of Confidentiality will be issued by 
the NIH. This certificate protects identifiable research information from forced disclosure. It allows 
the investigator and others who have access to research records to refuse to disclose identifying 
information on research participation in any civil, criminal, administrative, legislative, or other 
proceeding, whether at the federal, state, or local level. By protecting researchers and institutions 
from being compelled to disclose information that would identify research participants, Certificates 
of Confidentiality help achieve the research objectives and promote participation in studies by 
helping assure confidentiality and privacy to participants. 
13 Adverse events 
Assuring patient safety is an essential component of this protocol. Use of these agents for COVID-
19 raises unique safety considerations. This protocol addresses these considerations through: 
1. Exclusion criteria designed to prevent enrollment of patients likely to experience adverse 
events with receipt of these agents 
2. Proactive education of treating clinicians regarding medication interactions relevant to use of 
these agents in the inpatient setting 
3. On-study monitoring of co-interventions and patient characteristics to intervene before 
adverse events occur 
4. Systematic collection of outcomes relevant to the safety of these agents in this setting 
5. Structured reporting of adverse events 
The safety and monitoring approach in this platform is aligned with the expected impact of the 
investigational agents in the hospitalized COVID-19 population. All of the investigational agents 
have short half-lives, and it is expected their biologic effect would be seen during or shortly after 
treatment. Thus, the focus of safety monitoring through day 60 will be broad safety monitoring and 
reporting of serious adverse events felt to be at least possibly related to the investigational agent. 
Importantly, patients with COVID-19 often experience multisystem illness, including ARDS, cardiac 

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and renal injury. As a result, many anticipated serious adverse events will be collected as study 
outcomes (protocol-specified exempt serious events (PSESEs) as listed in section 13.2) and will be 
monitored by the DSMB rather than be subject to strict reporting criteria associated with adverse 
events. Adverse events and PSESEs will be monitored to ensure real-time participant protection. 
The safety evaluation of the study intervention includes several components to be reviewed 
regularly by the NHLBI-appointed independent DSMB.  
All other AEs are collected for the study intervention (either the blinded investigational agent or placebo). 
Events will be reported to regulators and IRBs/IECs as appropriate/required. 
Adverse events and unanticipated problems will be regularly reviewed by the DSMB.  
The following information will be collected on electronic case report forms, and will be regularly 
reviewed by the DSMB, to evaluate and help ensure safety: 
• 
Deaths through Day 90 
• 
Hospital readmissions through Day 60 
• 
Protocol-specified exempt serious events (PSESEs) (see section 13.2) through Day 60 
• 
Adverse Events that are Serious OR are Definitely or Possibly Related (or of Uncertain 
Relationship) OR are a Grade 3 or 4 Clinical AE (isolated laboratory abnormalities that 
are not associated with signs or symptoms are not collected)  
We outline the safety data collected in Table 2. 
 
Table 2.  
Overview of Safety Data Collection 
 
 Day 0–5 
Day 14 
Day 28 
Day 60 
Day 90 
All grade 3 and 4 clinical AEs 
(new or increased in severity 
to Grade 3/4) 
X 
Xa 
Xa 
Xa 
 
 
Protocol-specified exempt 
serious events (PSESEs)b 
X 
X 
X 
X 
 
 
Recordable AEs that are not 
PSESEs 
X 
X 
X 
X 
 
 
Unanticipated Problems  
X 
X 
X 
X 
 
Mortality  
X 
X 
X 
X 
X 
aParticipants will be asked about all new relevant adverse events which have occurred since the 
last data collection, up to that time point. On these visits, qualifying AEs will be collected. 
bThese are explained and defined in section 13.2. 
 
 
 

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13.1 Defining adverse events 
 
Adverse Events will be defined as any untoward medical occurrence associated with use of the 
study drug or study procedures, whether or not the event is related to the study drug or study 
procedures. If a diagnosis is clinically evident (or subsequently determined), the diagnosis, rather 
than the individual signs and symptoms or lab abnormalities, will be recorded as the AE.  
 
a. Seriousness:  
 
Serious Adverse Event will be defined as an adverse event that, in the view of the investigator, 
resulted in any of the following outcomes:  
1. Death 
2. A life-threatening event that places the patient at immediate risk of death 
o Does not include events that, had they been more severe, might have caused death 
3. Inpatient hospitalization or prolongation of existing hospitalization 
o As per http://www.fda.gov/Safety/MedWatch/HowToReport/ucm053087.htm 
4. Persistent or significant incapacity or substantial disruption of the ability to conduct 
normal life functions, or a congenital anomaly/birth defect 
o As per http://www.fda.gov/Safety/MedWatch/HowToReport/ucm053087.htm  
 
Important medical events that may not result in death, be life-threatening, or require hospitalization may 
be considered serious when, based on appropriate medical judgment, they jeopardize patient safety or 
require medical or surgical intervention to prevent one of the outcomes listed in this definition. 
b. Causality:  
A Related or Possibly Related Adverse Event will be defined as any adverse event for which 
there is a "reasonable possibility" of a causal relationship between the study drug or study 
procedure and the adverse event. For each recorded adverse event, investigators will grade the 
strength of the relationship of study drug or study procedure to the adverse event, as follows: 
o Definitely Related: The adverse event meets all three of the following criteria: (a) a temporal 
sequence from receipt of study drug or study procedure to the adverse event suggests 
relatedness, (b) the event cannot be explained by the known characteristics of the patient’s 
clinical state or other therapies, and (c) evaluation of the patient’s clinical state indicates to 
the investigator the experience is definitely related to study drug or study procedures.  
o Possibly Related: In the investigator’s opinion, the adverse event is possibly related to study 
procedures but one or more of the above criteria for “Definitely Related” are not met.  
o Probably Not Related: The adverse event occurred while the patient was on the study but, in 
the opinion of the investigator, can reasonably be explained by the known characteristics of 
the patient’s clinical state or other therapies.  
o Definitely Not Related: The adverse event was definitely produced by the patient’s clinical 
state or by other therapies and not by the study drug or study procedures.  
o Uncertain Relationship: The adverse event does not meet any of the criteria previously 
outlined.  
 
c. Expectedness:  
An Unexpected Adverse Event is defined as an adverse event that is not listed in the investigator 
brochure or study protocol or is not listed at the specificity or severity that has been observed.   

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d. Severity: 
The investigator will evaluate all AEs with respect to both seriousness (defined in 13.1.a. above) 
and severity (intensity or grade).  AEs will be graded for severity according to the DAIDS Table for 
Grading the Severity of Adult and Pediatric Adverse Events (also known at the DAIDS AE Grading 
Table). For specific events that are not included in the DAIDS AE Grading Table, the generic scale 
listed below is to be used: 
Generic AE Grading Scale 
 
Grade 1 
 
Events causing no or minimal interference with usual social and functional 
activities, and NOT raising a concern, and NOT requiring a medical 
intervention/ therapy. 
Grade 2 
Events causing greater than minimal interference with usual social and 
functional activities; some assistance may be needed; no or minimal 
medical intervention/therapy required. 
Grade 3 
Events causing inability to perform usual social and functional activities; 
some assistance usually required; medical intervention/therapy required.  
Grade 4 
Events causing inability to perform basic self-care functions; medical or 
operative intervention indicated to prevent permanent impairment, 
persistent disability, or death. 
Grade 5 
Events resulting in death. 
 
An Adverse Event of Special Interest (AESI) will be defined as a pre-specified event of scientific 
or medical concern that has the potential of being related to study drug and is important to 
understand regardless of investigator classifications.  AESIs included below will be recorded in the 
adverse event eCRF and will require a written narrative. 
13.2 Protocol-specified exempt serious events (PSESEs) 
Outcomes of acute respiratory infection, COVID-19, and critical illness will be systematically 
collected as Protocol-specified exempt serious events (PSESEs) for all patients.   
 
PSESEs are exempt from adverse event reporting unless:  
1. the event is determined to be Serious and Definitely or Possibly Related to the study drug or 
study procedures;  
2. the event is determined to be Unexpected and Definitely or Possibly Related to the study 
drug or study procedures; or  
 
This approach is taken to avoid creating an overly cumbersome safety oversight environment by 
identifying expected clinical outcomes as safety events and obscuring real safety signals. Even as 
they are exempted from expedited reporting requirements, PSESEs will be reviewed regularly 
(unblinded, by treatment arm) by the DSMB to maintain the integrity of safety monitoring for the 
trial. PSESEs that meet none of the criteria above will not be recorded or reported as AEs.  
PSESEs may occur during the initial hospitalization, lead to a re-admission, or occur in a later 
hospitalization during follow-up. The following are study-specific exempt serious events: 
 
• 
Death (not Definitely or Possibly Related to the study drug or study procedures) 
• 
Neurological Events: 
o Seizure 

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o Stroke  
• 
Cardiovascular Events:  
o Hypotension as defined by low arterial blood pressure leading to either [1] initiation 
or increase in vasopressor therapy, [2] administration of a fluid bolus of 500 ml or 
more, or [3] modification of the dose or discontinuation of the study drug.  
o Atrial or ventricular arrhythmia 
o Cardiomyopathy 
o Cardiac arrest 
o Myocardial injury  
o Acute coronary syndrome  
o Hypertension as defined by elevated arterial blood pressure leading to either [1] 
initiation or increase in antihypertensive medications or [2] discontinuation of the 
study drug  
• 
Respiratory events: 
o Hypoxemia requiring supplemental oxygen 
o Acute respiratory distress syndrome 
o Receipt of non-invasive or invasive mechanical ventilation 
o Receipt of extra-corporeal membrane oxygenation 
• 
Gastrointestinal events: 
o Elevation in aspartate aminotransferase or alanine aminotransferase 
o Acute pancreatitis 
• 
Renal events: 
o Acute kidney injury 
o Receipt of new renal replacement therapy 
• 
Endocrine events: 
o Symptomatic hypoglycemia 
• 
Hematologic or coagulation events: 
o Neutropenia, lymphopenia, anemia, or thrombocytopenia 
o Venous thromboembolism  
• 
Dermatologic events: 
o Severe dermatologic reaction (e.g., Steven’s Johnson Syndrome)  
 
A PSESE for “initiation of vasopressor therapy” should be recorded for patients who newly receive 
any vasopressor at a dose of at least 0.1 mcg/kg/min norepinephrine equivalents (see table).  A 
PSESE for an “increase in vasopressor therapy” should be recorded for patients receiving a 
vasopressor at a dose of at least 0.1 mcg/kg/min norepinephrine equivalents who experience a 
doubling of vasopressor dose compared to either the dose at the time of randomization or the 
lowest dose in the prior 24 hours. 
 

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Note: Consistent with this approach, sites will evaluate a potential adverse event to determine 
whether it is a PSESE. If it is not a PSESE, it will be recorded and reported as an adverse event as 
outlined below. If the event is a PSESE, it will be evaluated for relatedness and expectedness. If the 
event is Serious and Definitely or Possibly Related, Unexpected and Definitely or Possibly Related 
it will be recorded as both a PSESE and an Adverse Event. If the PSESE does not meet either of 
these three criteria, then the event will be recorded as a PSESE in the PSESE eCRF as a study 
outcome. A study-specific clinical outcome may also qualify as a reportable adverse event. For 
example, a ventricular arrhythmia the investigator considers Serious and Definitely or Possibly 
Related to the study drug would be both recorded as a study-specific clinical outcome and reported 
as a Serious and Definitely or Possibly Related Adverse Event. 
13.3 Monitoring and recording adverse events 
The principal investigator at each study site has the responsibility for the safety of the individual 
participants under his or her care. For inpatients through day 28, on a daily basis the investigator or 
designee will determine if any adverse event has occurred.  For each adverse event, the 
investigator will determine whether the adverse event was serious, whether it was definitely or 
possibly related to study drug or study procedures, whether it was unexpected, and of what severity 
it was. 
The following categories of adverse events will be recorded as AEs in the Adverse Event case 
report form: 
o Adverse Events that Qualify for Expedited Reporting: 
o Serious Unexpected, and Definitely or Possibly Related Adverse Events [also known 
as “Suspected Unexpected Serious Adverse Reactions” (SUSARs)]- adverse events 
that are considered by the investigator to be serious, unexpected, and definitely or 
possibly related to the study drug or study procedures 
o Adverse Events that Qualify for Recording and Routine Reporting through Day 60 
o Non-SUSAR adverse events that are ‘Serious and Definitely or Possibly Related or 
of Uncertain Relationship’ OR that are “Unexpected and Definitely or Possible 
Related or of Uncertain Relationship”, regardless of whether they are PSESEs 
o Non-SUSAR adverse events that are Serious and are not PSESEs 

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o Non-SUSAR adverse events that are Definitely Related, Possibly Related, or of 
Uncertain Relationship and are not PSESEs 
o Non-SUSAR adverse events that are Grade 3 or 4 Clinical AEs and are not PSESEs 
o AESIs will include a narrative and will be reported in a routine manner 
13.4 Reporting adverse events 
This section describes the schedule for recording and reporting different types of safety events on 
eCRFs. In the care of study participants more information may be collected and recorded in the 
participant’s medical record. The information collected in the medical record serves as source 
documentation of events (e.g., signs, symptoms, diagnoses) considered for reporting on eCRFs as 
part of protocol data collection. 
 
13.4.1 Adverse Events that Qualify for Expedited Reporting 
Adverse Events that qualify for Expedited Reporting include events that: are Serious, Unexpected 
and Definitely or Possibly Related (also known as Suspected Unexpected Serious Adverse 
Reactions, SUSARs.  Adverse Events that qualify for Expedited Reporting (SUSARs) must be 
reported to the coordinating center by site investigators within 24 hours of site investigators 
becoming aware of the adverse event. The investigator at the study site or designee should inform 
the clinical coordinating center both by telephone and by official notification via completion of the 
Adverse Event case report form (Figure 2). The Medical Monitor may discuss with the site PI to 
determine if this event meets criteria for requiring Expedited Reporting (SUSAR). Events requiring 
Expedited Reporting (SUSARs)will be reported by the clinical coordinating center to the DSMB, 
sIRB, FDA and NHLBI within 7 calendar days of receipt of the report from the study site (as well as 
CA, IECs and other bodies per applicable local regulations for ex-U.S. sites). A copy of the Adverse 
Event case report form will be sent to the FDA, DSMB, sIRB, and NHLBI and appropriate regulatory 
bodies for ex-U.S. sites per applicable local regulations within 14 calendar days of receipt of the 
report from the study site. Adverse Events requiring Expedited Reporting (SUSARs) are followed 
until the outcome of the Adverse Event is known. If the outcome of an Adverse Events is still 
unknown at the time of the final follow-up visit, the outcome will be entered in the database as 
“unknown.” 
In parallel, non-U.S. participant SAEs should be reported to the NEAT ID Sponsor using the study 
specific Safety Event Reporting Form (SERF), within 24 hours of a member of the study team 
becoming aware of the event via e-mail to Safety@rokcservices.com or via the fax number 
provided on the SERF. 
 
For non-U.S. participants, processing of relevant safety events, including expedited SAE reporting 
pertinent to those ex-US territories, including electronic reporting via EudraVigilance of suspected 
unexpected serious adverse reactions (SUSARs) via ICH E2B compliant safety reports 
(ICSRs/acknowledgements) will be in line with Directive 2001/20/EC Detailed guidance on the 
collection, verification and presentation of adverse event/reaction reports arising from clinical trials 
on medicinal products for human use (CT-3). 
 
Adverse Events, that qualify for recording, but do not qualify for Expedited Reporting (i.e., adverse 
events that are not SUSARs), will be recorded on the Adverse Event eCRF through day 60. The 
DSMB will review all recorded adverse events during the scheduled meetings. The clinical 
coordinating center will distribute the written summary of the DSMB’s review including the review of 
adverse events to the sIRB. If the DSMB determines the overall rate of adverse events is higher in 

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the intervention group than the control group, the coordinating center will notify the sIRB and the 
Food and Drug Administration within 14 calendar days of this determination. 
All deaths are reported on the eCRF for deaths. Deaths considered definitely or possibly related 
to the study intervention (blinded investigational agent/placebo) must also be reported as an AE 
and may qualify for Expedited Reporting.  
 
All deaths that are felt to be possibly or definitely related to study drug would be unexpected (for    
reporting purposes). 
 
Unanticipated problems are findings discovered during the conduct of the trial that suggest 
participation in the trial may have more risk than was anticipated prior to the initiation of the trial.  
Unanticipated problems will also be reported within 14 days of the coordinating center learning 
about them to the DSMB and NHLBI.  
13.4.2 Grade 3 and 4 Clinical Adverse Events 
From Day 0 through Day 60, Clinical Adverse Events that are not PSESEs reaching Grade 3 or 4 
severity level will be recorded on an eCRF. For a Clinical Adverse Event that was present at 
baseline, only those newly reaching Grade 3 or 4 will be recorded. 
 
Clinical Adverse Events that are not PSESEs reaching Grade 3 or 4 severity level that occur between 
days 0 through 60 will be recorded on an eCRF at the time of phone follow-up. The date the event 
reaches the indicated grade will be collected to permit time-to-event analyses. These Clinical Adverse 
Events should be assessed for seriousness, relatedness, expectedness, severity (Section 13.3) and 
unanticipated problems. These events should be reported on the Adverse Event eCRF. 
13.4.3 Pregnancy 
The investigator or designee will collect pregnancy information on any female participants who 
become pregnant up to 30 days after receiving study drug unless indicated differently in the drug-
specific appendix. The participant will be followed to determine the outcome of the pregnancy.  
 
 
 

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Figure 1.  
Adverse Event and Clinical Outcome Assessment, Recording, and Reporting 
 
 
 
 
 
 

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13.5 Medical Monitor 
An experienced medical monitor is assigned to the trial. The medical monitor will work with the site 
PI and study team to review Adverse Events that potentially require Expedited reporting and make 
an assessment of seriousness, relatedness, expectedness, and severity. The medical monitor will 
work with the Coordinating Center to prepare sponsor safety report and communicate as needed 
with the DSMB and the Investigational New Drug (IND) holder through the study safety office or 
other mechanism mutually agreed to and documented. An Urgent Safety Measure (USM) is a 
procedure which is not defined by the protocol that can be put in place to protect clinical trial 
participants from any immediate hazard to their health and safety. It is the responsibility of the 
investigator to apply the appropriate level of USM for the safety and protection of each participant 
in this study in order to prevent harm. USMs may be applied immediately without prior approval 
from the sponsor, competent authority (CA) or IRB/IEC. However, they must be reported to the 
sponsor and to the PI immediately (within 24 hours) who will then inform the CA and IRB/IEC 
according to local regulation. In addition to the expedited safety reporting mentioned above, the ex-
US sponsor (NEAT-ID) will provide Development Safety Update Reports (DSURs) once a year 
throughout the clinical trial, or on request, to the CA and IRB/IEC. The report will be submitted 
within 60 days of the Developmental International Birth Date (DIBD) of the trial each year until the 
trial is declared ended or as per local regulation, if different.  
 
The medical monitor will remain blinded in all discussions with the study team regarding expedited 
reporting and recording to perform an unbiased assessment of seriousness, relatedness, 
expectedness, and severity. In the event the monitor and clinical team feel that unblinding is 
needed for safety purposes the monitor will communicate this with the Coordinating Center for 
documentation purposes who will confer treating assignment to the medical monitor. When this 
occurs, an alternate medical monitor will be utilized to review the AE with the study team to 
determine seriousness, severity, and relatedness. 
 
The medical monitor or the DSMB may request enrollment be halted for safety reasons (e.g., 
unacceptably high rate of Serious Adverse Events). If the treatment arm is temporarily halted or 
stopped for safety reasons, IRBs/ethics committees will be informed. The IND holder(s) and 
sponsor(s), in collaboration with the protocol chair and the DSMB, will determine if it is safe to 
resume the study. The sponsor will notify the Site Investigators of this decision. The conditions for 
resumption of the study will be defined in this notification. The Site Investigators will notify their 
local IRBs/ethics committees of the decision to resume the study. 
14 Risk Assessment 
14.1 Potential risks of other study procedures 
See agent-specific appendices for agent-specific safety risks.   
14.2 Minimization of risk 
Federal regulations at 45 CFR 46.111(a)(1) require that risks to participants are minimized by using 
procedures which are consistent with sound research design. This trial protocol incorporates 
numerous design elements to minimize risk to patients that meet this human subject protection 
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14.3 Potential benefit 
Study participants may or may not receive any direct benefits from their participation in this study. 
Administration of these agents may improve clinical outcomes among adults hospitalized for 
COVID-19 infection.  
14.4 Risk in relation to anticipated benefit 
Federal regulations at 45 CFR 46.111 (a)(2) require “the risks to subjects are reasonable in relation 
to anticipated benefits, if any, to subjects, and the importance of the knowledge that may 
reasonably be expected to result.” Based on the preceding assessment of risks and potential 
benefits, the risks to subjects are reasonable in relation to anticipated benefits All agents have an 
acceptable safety profile and have been or are currently being studied in Phase 2 trials of patients 
with COVID-19. As new agents are added, any change in risks in relation to anticipated benefit will 
be described in the agent-specific appendix. 
15 Data and Safety Monitoring Board (DSMB) 
The role of the DSMB is to monitor patient safety and integrity of the trial. The full details of the 
DSMB will be provided separately by NHLBI in the DSMB charter. We outline the role of the DSMB 
here. The independent DSMB will be comprised of individuals with appropriate expertise such as 
clinician scientists in critical care, emergency medicine, pulmonology, nephrology, cardiology, trial 
design, biostatistics, and ethics. The DSMB will review reports. Any post-randomization or 
outcomes data presented by treatment group in reports will be prepared by unmasked statisticians 
not otherwise involved with trial conduct or design decisions, who will conceal such information from 
the investigator team. These unmasked statisticians will compute the efficacy and inferiority criteria 
at regular intervals as described previously. The DSMB chairperson will be alerted to any decision 
threshold for stopping being met. Beyond assessing fidelity to pre-specified adaptations, the 
principal role of the DSMB is to assure the safety of participants in this trial. They will regularly 
monitor data from this trial, review and assess the performance of its operations, and make 
recommendations with respect to aspects of trial conduct such as: 
• 
Adverse events 
• 
Evidence of efficacy or adverse events 
• 
New external information, early attainment of study objectives, safety concerns 
• 
Possible modifications in the clinical trial protocol  
• 
Inadequate performance of the trial overall  
 
16 Data Handling and Record Keeping 
16.1 Data Collection and Management Responsibilities 
Data collection is the responsibility of the delegated clinical trial staff at the site under the 
supervision of the site investigator. The investigator is responsible for ensuring the accuracy, 
completeness, legibility, and timeliness of the data reported. 
All source documents should be completed in a neat, legible manner to ensure accurate 
interpretation of data.   
Source document worksheets for recording data for each participant enrolled in the study will be 
provided as needed.  Data recorded in the eCRF derived from source documents should be 
consistent with the data recorded on the source documents.  
Clinical data (including AEs, concomitant medications, and expected adverse reactions data) and 
clinical laboratory data will be entered into secure, compliant data capture systems provided by the 

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Data Coordinating Center. The data system includes password protection and internal quality 
checks, such as automatic range checks, to identify data that appear inconsistent, incomplete, or 
inaccurate.  
16.2 Study Records Retention 
Per FDA regulation 312.62C, study documents should be retained for a minimum of 2 years after 
the last approval of a marketing application in an International Conference on Harmonization (ICH) 
region and until there are no pending or contemplated marketing applications in an ICH region or 
until at least 2 years have elapsed since the formal discontinuation of clinical development of the 
study intervention. Study documents may be retained for a longer period, however, if required by 
local regulations. No records will be destroyed without the written consent of the sponsor, if 
applicable. It is the responsibility of the sponsor to inform the investigator when these documents no 
longer need to be retained.  
16.3 Protocol Deviations 
A protocol deviation is any noncompliance with the clinical trial protocol and GCP requirements. 
The noncompliance may be either on the part of the participant, the investigator, or the study site 
staff. As a result of deviations, corrective actions are to be developed by the site and implemented 
promptly. 
 
It is the responsibility of the site PI/study staff to use continuous vigilance to identify and report 
deviations. 
Protocol deviations must be reported to the sIRB per their guidelines. The site PI/study staff is 
responsible for knowing and adhering to requirements for reporting protocol deviations to the study 
coordinating center and sIRB, and these details will be included in the platform MOP. Where 
applicable in ex-US territories, guidelines for reporting serious breach of protocol and GCP to the 
appropriate regulatory bodies will be followed. 
16.4 21 CFR Part 11 Compliance 
 
16.4.1 Record locking 
This trial will utilize the REDCap record-locking feature, that will allow the users to lock a participant 
record. A complete audit trail of the locked records will be kept in the data instrument’s history log. 
Users will receive a prompt when locking an entire record. They will be asked to review a PDF copy 
of the entire record to confirm it is the correct record and/or file.  Once the PDF has been reviewed 
and confirmed, the record will be locked. All records that are locked using record-level locking will 
have a duplicate copy of the Portable Document Format (PDF) file automatically stored on a secure 
file server outside of REDCap. The record-locking feature complies with all the requirements 
described in 21 CFR Part 11 for FDA trials and has been validated at VUMC. 
16.4.2 eConsent  
Informed consent should follow both local institutional policy and national regulatory guidance. One 
option in this trial is to utilize the REDCap eConsent feature. VUMC has developed an electronic 
consent (eConsent) framework within the REDCap platform allowing research participants to rapidly 
review and sign consent documentation for delivery via web, tablet, or smartphone. Electronic 
consent forms can leverage standard REDCap survey features including multi-lingual language 
capacity for information rendering and capture. Upon completion, the system documents the 

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‘consent transaction’ and stores final, “frozen” consent PDFs in REDCap, allowing researchers to 
retrieve information on the consent type, status, and version at any time. Consents are also stored 
in a separate secure document system for redundancy and permanent archival. The REDCap 
eConsent framework has been 21 CFR Part 11 validated at VUMC. 
17 End of Trial 
The “end of the trial” occurs when patient enrolment, follow-up, data cleaning and analysis have 
been completed. 
18 Study Finances 
18.1 Funding Source 
Support for studies conducted under the protocol includes funding from the National Institutes of 
Health. 
18.2 Costs to the Participant 
In sites and countries where health insurance is applicable, participant health insurance may be 
billed for the costs of medical care and activities occurring outside this protocol. If their insurance 
does not cover these costs or participants do not have insurance, these costs will be participant 
responsibility. 
Activities of the sub studies may take advantage of standard of care activities for collecting 
information, such as at routine follow-up visits. Such visits will generally be charged to insurance 
unless the visit is required only for research. At mixed visits where both research and clinical care 
occur such as for inpatients enrolled in this trial, clinical care will generally be charged to insurance. 

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19 Appendix A: Primary study outcomes 
19.1 Approach to ascertainment and verification of outcomes 
Outcomes will be assessed locally and will not be centrally adjudicated unless specified in the arm-
specific appendix. Outcomes should be assessed by a local investigator or other qualified study 
team member who is blinded to treatment assignment. 
19.2 Primary outcome: Oxygen free days  
The primary outcome for this platform is oxygen free days through day 28 (OFD). OFD is a clinically 
relevant, longitudinal measure of lung function and mortality for the first 28 days after 
randomization. OFD will be calculated using principles developed during the past 20 years for other 
free-day clinical trial outcomes, including ventilator free days,32,33 organ support free days,34 and 
hospital free days.35  Free-day outcomes have also been successfully utilized in COVID-19 clinical 
trials.36  
 
OFD will be calculated as the number of calendar days during the first 28 days after randomization 
during which the patient was alive and not receiving supplemental oxygen by nasal cannula, face 
mask, high flow nasal cannula (HFNC), non-invasive ventilation (NIV), invasive mechanical 
ventilation (IMV), or extracorporeal membrane oxygenation (ECMO). The day of randomization is 
denoted as Day 0. Starting with calendar day 1 (the day after randomization) and continuing for 28 
days, study personnel will document whether supplemental oxygen therapy was received for any 
duration. While the patient is in the hospital, the highest level of respiratory support will be classified 
daily according to the 8-category WHO COVID-19 clinical status scale (Table 3).48 Calendar days 
on which the patient received supplemental oxygen (category 4), HFNC or NIV (category 5), or IMV 
or ECMO (categories 6 and 7) will be classified as a day with oxygen use.   
 
After hospital discharge, patients will be assessed for home oxygen use via serial telephone follow-
up calls to the patient or surrogate. During these calls, study personnel will assess for new home 
oxygen use with the following questions: 
 
(1) Were you discharged from the hospital on oxygen? 
 
(2) Did you use oxygen at any time after hospital discharge? 
 
(3) Are you still using oxygen? 
(4) If you received oxygen at any time after hospital discharge and are no longer on oxygen, 
what was the last day you used oxygen at home?  
 
Patients who chronically used supplemental oxygen prior to their COVID-19 illness will be 
considered oxygen free when they return to the same level of oxygen support, they had been using 
prior to COVID-19 illness. For example, a patient who chronically used supplemental oxygen at 4 
liters per minute via nasal cannula before COVID-19 and who was intubated for acute management 
of COVID-19 would be considered oxygen free for calculation of the primary outcome when he/she 
returned to oxygen support via nasal cannula at 4 liters per minute or less. 
 
Data collected reflecting the patient’s status after day 28 will not be used for the calculation of OFD. 
OFD will be calculated as 28 minus the number of days with supplemental oxygen use during the 
first 28 days following randomization. OFD will be coded as -1 for patients who died before study 
day 28. Hence, the range for OFD is from -1 to 28 days. Examples of OFDs are shown in Table 4. 
Some patients will enter the trial with supplemental oxygen use (enrolled while in WHO category 4, 
5, 6 or 7), while others will enter the trial without oxygen therapy (enrolled while in WHO category 
3).   

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Table 3.  
WHO COVID-19 Clinical Status Scale and its use for enrollment eligibility and 
 
 
calculation of oxygen free days (OFD) 
Category 
Category Description 
Notes for eligibility 
(baseline status) 
Notes for OFD calculation (daily 
status on days 1 – 28) 
1 
Not hospitalized without 
limitation in daily activity 
Patients in category 1 at 
baseline are not eligible for 
enrollment. 
 Classified as oxygen free day 
2 
Not hospitalized with 
limitation in daily activity 
or home oxygen use 
Patients in category 2 at 
baseline are not eligible for 
enrollment. 
Days with home oxygen use are 
classified as days with 
supplemental oxygen. Days at 
home with limitations in daily 
activity but with no home oxygen 
use are classified as oxygen free 
days. 
3 
Hospitalized not on 
supplemental oxygen  
Patients in category 3 at 
baseline are not eligible for 
enrollment. 
Classified as oxygen free day 
after enrollment  
4 
Hospitalized on standard 
supplemental oxygen via 
nasal cannula or mask 
Eligible for enrollment 
Classified as day with 
supplemental oxygen use  
5 
Hospitalized on high-flow 
nasal cannula or non-
invasive ventilation  
Eligible for enrollment 
Classified as day with 
supplemental oxygen use 
6 
Hospitalized on invasive 
mechanical ventilation 
without other organ 
support 
Eligible for enrollment 
Classified as day with 
supplemental oxygen use 
7 
Hospitalized on invasive 
mechanical ventilation 
and other organ support 
(including vasopressors, 
RRT or ECMO) 
Eligible for enrollment 
Classified as day with 
supplemental oxygen use 
8 
Death 
Patients who die before 
randomization are not 
eligible for enrollment 
Death at any time prior to the 
earlier of hospital discharge or day 
28 is coded as -1 OFD 
The baseline (pre-randomization) clinical status will be used to determine eligibility for enrollment. Clinical 
status will be scored every day the patient is in the hospital through day 28; these daily scores will be used to 
calculate OFD.  
 
 
 
 
 
 
 
 

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Table 4.  
Descriptions of OFD Data 
 
OFD (days) 
Description 
More 
Severe 
-1 
Patient died before the end of day 28. 
 
0 
Patient survived through day 28 and had oxygen use on every calendar day 
between day 1 and day 28. 
1 
Patient survived through day 28 and was free from oxygen use for 1 
calendar day in the first 28 days following randomization. The patient was on 
nasal cannula, face mask, HFNC, NIV, IMV or ECMO on 27 of the first 28 
calendar days following randomization.    
10 
Patient survived through day 28 and was free from oxygen use for 10 days in 
the first 28 days following randomization. The patient was on nasal cannula, 
face mask, HFNC, NIV, IMV or ECMO on 18 of the first 28 calendar days 
following randomization.      
25 
Patient survived through day 28 and was free from oxygen use for 25 days in 
the first 28 days following randomization. The patient was on nasal cannula, 
face mask, HFNC, NIV, IMV or ECMO on 3 of the first 28 calendar days 
following randomization.     
 
Less 
Severe 
28 
Patient survived through day 28 and was free from oxygen use on every 
calendar day after the day of randomization (Day 0) for the first 28 days of 
follow-up. The patient did not receive oxygen by nasal cannula, face mask, 
HFNC, NIV, IMV, or ECMO at any time between day 1 and day 28.  
19.3 Definitions 
 
19.3.1 ICU Level of care 
Defined as planned admission to ICU.   
19.3.2 Myocardial injury 
Myocardial injury will be defined as an increase in troponin above the 99th percentile with or without 
ECG changes consistent with ischemia. This diagnosis is made locally. 
19.3.3 Acute Kidney Injury 
Acute kidney injury after enrollment is defined by KDIGO criteria for Acute Kidney Injury in the 
setting of not meeting these criteria upon enrollment. We will define AKI as Stage 2 or higher for 
purposes of our AKI outcome: 
     THREE STAGES: 
• 
Stage 1: Serum Cr 1.5–1.9 times baseline, OR ≥ 0.3 mg/dl increase in serum Cr 
• 
Stage 2: Serum Cr 2.0–2.9 times baseline 
• 
Stage 3: Serum Cr ≥ 3.0 times baseline OR Increase in serum creatinine to ≥ 4.0mg/dl, OR 
Initiation of renal replacement therapy 
 
19.3.4 Disseminated Intravascular Coagulation (DIC) (Overt) – DIC score ≥ 5 
1. Platelet count ≥ 100 K (0); 50–100K (1 point); < 50K (2 points) 

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2. Elevated D-dimer: no increase (0 points); moderate increase (1 point); severe increase (3 
points) according to local criteria. 
3. Prolonged PT < 3 seconds (0 points); 3–6 seconds (1 point); ≥ 6 seconds (2 points) 
4. Fibrinogen level ≥ 100 (0 points); < 100 (1 point) mg/dL 
 
19.3.5 ISTH Defined Major Bleeding 
Bleeding that: 
1. Resulted in death,  
2. Occurred in a critical organ (intracranial, intraspinal, intraocular, retroperitoneal, 
intraarticular, intramuscular with compartment syndrome, or pericardial), or 
3. Associated with either a decrease in the hemoglobin level of at least 2 g per deciliter or a 
transfusion of at least 2 units of packed red cells 
 
 

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20 Appendix B: Data and Safety Monitoring Plan 
20.1 Overview 
The purpose of a monitoring plan is to facilitate compliance with good clinical practice guidelines 
and federal regulations by: documenting a plan for verifying that the rights and well-being of 
participants are protected; the reported trial data are accurate, complete and verifiable from source 
documents; the confidentiality of participant data is maintained; serious adverse events and 
unanticipated problems are adequately addressed; and the trial is conducted in compliance with the 
protocol, prevailing SOPs, federal regulations, and other relevant requirements. The full Data and 
Safety Monitoring plan is described in detail in a separate document. The scope and content of this 
monitoring plan is based on the objective, purpose, design, and complexity of this platform, which is 
a multi-arm, blinded, randomized placebo-controlled trial. The safety profile of the selected agents 
being considered for this platform is based on prior clinical trials in patients with acute illness, both 
COVID-19 and non-COVID-19 related. Thus, a monitoring approach of surveillance and reporting of 
serious adverse events is sufficient. The trial is designed to enroll subjects at multiple sites, to 
include within-site randomization. A comprehensive project and data management system is in 
place to support real-time review of regulatory compliance, screening, enrollment, and data integrity 
with automated reporting to the study team. A risk management plan will also be deployed. 
Intensive patient monitoring in the clinical setting during and immediately following treatment is 
planned. These features mitigate risks from conduct of the trial and suggest verification of consent, 
eligibility, and primary outcomes with targeted verification of other data are sufficient to ensure 
study integrity and protection of the rights and welfare of participants. The data and safety 
monitoring plan will be approved by the DSMB prior to enrolling patients in this trial. The details of 
the scope of monitoring, monitoring personnel, site visits (remote and in-person) are delineated in 
the separate DSMP document.  
 
 
 

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21 Appendix C: Minimum Biological Specimen collection 
Baseline specimens to be collected 
Sample Processing 
Biorepository 
 
Study-specific biospecimen collection for exploratory outcomes will be collected, when possible, at 
participating U.S. Sites.  
 
Blood collection times (4 total timepoints): 
• 
Baseline—at time of randomization (Study Day 0).  
• 
Two time points on study drug (Study Day 1 + 1 day and Study Day 3 ± 1 day) 
• 
Within 2-36 hours after inpatient study treatment ends (or any time on Study Day 5 + 36 
hours for final blood collection in the Fostamatinib arm for those still hospitalized at Day 5) 
 
Standard samples to be collected & volumes at each time point: 
• 
Plasma – 30.4 mL 
• 
Serum – 6 mL 
• 
Total blood collection at each time point = 36.4 mL 
o  
Peptides/enzymes to be measured at each time point: 
• 
1st priority: 
o  Ang-(1-7), Ang II, NT-proBNP and hsTn, (plasma, collected in pretreated tubes) 
o ACE, ACEII activity and level, (serum)  
• 
2nd priority: 
o Renin, Ang I, Neprilysin, Prolyl oligopeptidase  
 
Supplies: 
• 
Source – The University of Vermont: packages sent to sites with EDTA plasma tubes 
(inhibitor cocktail) including labels and special tubes   
• 
Sites – Batch shipping (overnight on dry ice)  
 
Note 1: We anticipate that some sites may not be able to collect & process all the samples and time 
points listed above. We plan to work with those sites to identify more limited time points and/or 
discarded samples that could be collected, processed, and sent to the biorepository. 
Note 2: If a participant’s blood specimens are unable to be obtained at the timepoints outlined in 
the protocol due to unforeseen circumstances such as a non-functioning IV, or the patients desire to 
not have blood drawn, this will not be considered a protocol violation.  
 
 
 

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22 Appendix D: Arm 3: Fostamatinib 
22.1 Description of active therapy 
Fostamatinib is an oral spleen tyrosine kinase inhibitor FDA approved for the treatment of adult 
patients with chronic immune thrombocytopenia (ITP) who have had insufficient response to previous 
treatment. Fostamatinib is a prodrug with an active metabolite, R406. R406 is protein bound and has a 
half-life of 15 hours, with 80% of excretion occurring in feces and 20% excreted in urine.  
22.2 Rationale for evaluating Fostamatinib 
Spleen tyrosine kinase is a cytoplasmic tyrosine kinase that signals through Fc receptors, B-cell 
receptors, and c-type lectin receptors. Robust antibody responses are associated with severe 
disease in COVID-19 and may drive thromboinflammation. In vitro evidence suggests, R406, the 
active component of fostamatinib, can inhibit the release of cytokines by macrophages and platelet-
mediated thrombosis provoked by SARS-CoV-2 specific spike antigen/antibody complexes. R406 
also inhibits the release of neutrophil extracellular traps from neutrophils stimulated with plasma 
from patients with COVID-19, ultimately resulting in decreasing immunothrombosis. A recent 
placebo-controlled randomized phase 2 study in hospitalized adults with Covid-19 (NCT04579393) 
suggested fostamatinib in addition to usual care was safe and did not result in more serious 
adverse events (10.5% in the fostamatinib group vs. 22% in the placebo group). Additionally, 
multiple secondary efficacy endpoints showed trends favoring the patients receiving fostamatinib, 
including 28-day mortality, days free of oxygen, and recovery as measured on the 8-point ordinal 
scale at day 15.  
 
 

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Figure 2.  
Spleen tyrosine kinase inhibition in COVID-19 (Strich, Generated using  
 
 
Biorender) 
 
22.3 Fostamatinib dose, duration, and route of administration 
We will use a study dose of 150mg orally twice daily for 14 days (28 doses). This regimen was 
studied in the recently completed phase 2 trial in patients hospitalized with COVID-19. The dose 
may be modified to 100mg according to pre-defined criteria in section 22.7 (Dose Modification 
Considerations and Medication Interactions). Study medication will be continued as an outpatient if 
the patient is discharged prior to completing 28 doses. If necessary, in patients unable to swallow, 
tablets can be crushed until granular with an approximate particle size <2 mm, added to 
approximately 10 mL of water, and stirred to mix before administration through an enteral tube. 
 
While many patients on BiPAP can safely receive oral medications, it may be potentially unsafe to 
administer oral medications to patients at certain times while they are receiving BiPAP therapy due 
to risk of hypoxemia if the mask is removed and/or risk of aspiration if an oral medication is 
administered and BiPAP is immediately re-initiated. Determining whether an oral medication should 
be given to a patient receiving BiPAP therapy is a bedside clinical decision.  
The goal is to administer two doses of study medication each calendar day and approximately 12 
hours apart from one another. If the time between study medication doses needs to be reduced, the 
recommendation is to administer two doses at least 4 hours apart from one another. If a dose of 
study medication is entirely skipped, a missed dose should be noted in the electronic data capture 

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system (REDCap). Skipped doses are not “made up” by extending the dosing period; patients 
should only receive study drug for a maximum of 14 days, starting with randomization. 
22.4 Placebo 
The drug product is provided by Rigel Pharmaceuticals, Inc., and consists of 2 strengths of orange 
film-coated, plain, bioconvex tablets. The 150 mg tablet is oval, and the 100 mg tablet is round. The 
tablets are supplied in white opaque high-density polyethylene bottles capped with white 
polypropylene child resistant closures with foil induction seals. Placebo tablets to match 
fostamatinib 100 mg and 150 mg will be provided by Rigel Pharmaceuticals, Inc. An unblinded 
pharmacist at each study site will dispense and record randomization and treatment assignment.  
22.5 Fostamatinib-specific safety considerations and potential medication interactions 
Fostamatinib has a consistent safety profile, with the most common adverse reactions (≥5% and 
more than placebo) being diarrhea, hypertension, nausea, respiratory infection, dizziness, ALT/AST 
increase, rash, abdominal pain, fatigue, chest pain and neutropenia. Warnings and precautions 
included in the US product label include hypertension, elevated liver function tests, diarrhea, 
neutropenia, and embryo-fetal toxicity.  
 
• 
Fostamatinib must be discontinued in case the patient becomes pregnant. 
 
• 
Concomitant use with strong CYP3A4 inhibitors with fostamatinib will increase exposure to 
the active metabolite R406 and may result in increased risk of adverse reactions. Therefore, 
patients that cannot have strong CYP3A4 inhibitors held should be excluded from the 
Fostamatinib arm. Strong CYP3A4 inhibitors that should exclude patients from the 
fostamatinib arm include: Atazanavir, Certinib, Clarithromycin, Cobicistat and cobicistat-
containing coformulations, Idelalisib, Indinavir, Itraconazole, Ketocanazole, 
Levoketoconazole, Lonafarnib, Lopinavir, Mifepristone, Mibefradil, Nefazodone, Nelfinavir, 
Ombitasvir-paritaprevir-ritonavir plus dasabuvir, Posaconazole, Ribociclib, Ritonavir, 
Saquinavir, Telithromycin, Troleandomycin, Tucatinib, Voriconazole. Novel strong CYP3A4 
inhibitors may be released after the writing of this protocol appendix. If you anticipate the 
patient will require a strong CYP3A4 inhibitor that is not included in the list above, please 
reference this regularly updated list:  https://drug-
interactions.medicine.iu.edu/MainTable.aspx 
  
Fostamatinib itself is a weak CYP3A4 inhibitor and will result in a modest (~1.25 fold) 
increase in CYP3A4 substrates. Medications processed (activated or deactivated) by the 
CYP3A4 enzyme are here referred to as CYP3A4 substrate medications. Concomitant use 
of CYP3A4 substrate medications with Fostamatinib will modestly decrease the processing 
of the CYP3A4 substrate medication. If possible, CYP3A4 substrate medications should be 
held or have another medication substituted for them. Due to its modest effects, concomitant 
use of CYP3A4 substrate medications is not an exclusion criterion for this trial. However, 
investigators should carefully consider inclusion of patients taking CYP3A4 substrate 
medications with narrow therapeutic windows and should monitor closely for toxicities.  
• 
For a full list of CYP3A4 substrates, please reference this regularly updated list: https://drug-
interactions.medicine.iu.edu/MainTable.aspx.  

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• 
All participants who are randomized to this arm should refrain from drinking alcohol while 
taking study drug.  
 
• 
Once discharged, WOCBP must agree to use effective contraception to not get pregnant 
between the first dose of study drug and 30 days after the last day of study drug.  
 
Effective contraception is defined as:  
o A tubal ligation: for many teratogenic (and mutagenic) products, tubal ligation is 
considered a form of contraception, not a form of surgical sterilization (e.g., 
hysterectomy, bilateral oophorectomy).  
o An approved hormonal contraceptive such as oral contraceptives, emergency 
contraception used as directed, patches, implants, injections, rings, or hormonally 
impregnated intrauterine device (IUD). 
Less effective contraception is defined as: 
o  A form of less effective contraception is defined as Barrier methods (such as a 
condom used with or without a spermicide or a diaphragm or cervical cap used with 
a spermicide). 
22.6 Fostamatinib Arm-Specific Exclusion Criteria 
The following exclusion criteria differ from the master protocol criteria: 
1. Randomized in another trial evaluating fostamatinib in the prior 30 days  
 
Study arm exclusion criteria measured within 24 hours prior to randomization: 
1. AST or ALT ≥ 5 × upper limit of normal (ULN) or ALT or AST ≥ 3 × ULN and total bilirubin ≥ 2 × 
ULN 
2. SBP > 160 mmHg or DBP > 100 mmHg at the time of screening and randomization 
3. ANC < 1000/mL 
4. Patient is anticipated to require a strong CYP3A inhibitor (Atazanavir, Certinib, Clarithromycin, 
Cobicistat and cobicistat-containing coformulations, Idelalisib,Indinavir, Itraconazole, 
Ketoconazole, Levoketoconazole, Lonafarnib, Lopinavir, Mifeprostone, Mibefradil, Nefazodone, 
Nelfinavir, Ombitasvir-paritaprevir-ritonavir plus dasabuvir, Posaconazole, Ribociclib Ritonavir, 
Saquinavir, Telithromycin, Troleandomycin, Tucatinib, Voriconazole) from randomization to 21 
days post-randomization. For a full list of CYP3A4 substrates, please reference this regularly 
updated list: https://drug-interactions.medicine.iu.edu/MainTable.aspx.  
 
5. Patient unable to participate or declines participation in the fostamatinib arm.  
22.7 Dose Modification Considerations and Medication Interactions  
 
Dose Modifications: The following dose modifications will be utilized in patients randomized to the 
fostamatinib arm (active or placebo). Those patients who have doses held will only complete 14 
days (up to 28 doses) of study treatment. Dosing will not extend beyond day 14. Blood pressure will 
be monitored daily in the hospital while on study drug up until the time of discharge.  
 
Hypertension:  

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Blood pressure >140/90 should be treated with antihypertensives per usual care.  
 
During the inpatient hospitalization:  If systolic BP remains > 160 mmHg or diastolic BP > 100 
mmHg or higher despite antihypertensive therapy, interrupt study drug. When restarting study drug 
once BP is below 160 mmHg systolic and 100 mmHg diastolic, drug dose should be reduced to 100 
mg twice daily or matching placebo for the remainder of the study. 
 
• 
At the time of Hospital discharge: Patients still on study drug at the time of hospital 
discharge will have the following study procedures performed (see Figure 3): 
 
Figure 3.  
Schematic overview of blood pressure considerations and procedures  
 
 
performed for patients still on study drug at the time of hospital discharge 
 
 
 
1) Those with SBP < 160 mmHg and DBP < 100 mmHg will continue on study drug at the inpatient 
dose and have no further BP measurements for study purposes 
2) Those with SBP > 160 mmHg or DBP > 100 mmHg at the time of hospital discharge will have 
study medication stopped and undergo the following repeat testing:  
 
1) 7 (+/-2) days after post-hospital discharge a repeat blood pressure will be obtained.  
a. If the SBP is < 160 mmHg and DBP is < 100 mmHg no further BP monitoring will be 
performed for study purposes  
b. If the SBP is > 160 mmHg or the DBP is > 100 mmHg a follow-up will be performed 
in 7 (+/-2) days after the prior visit  
i. At the repeat visit if the SBP is < 160 mmHg and DBP is < 100 mmHg no 
further BP monitoring will be performed for study purposes  
ii. At the repeat visit if the SBP is > 160 mmHg or DBP is > 100 mmHg study 
guidance will recommend BP recheck by a healthcare provider   

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Hepatotoxicity: 
Inpatient monitoring: Liver function tests (LFT’s) will be checked daily during hospitalization while 
on study drug.   
1) Study drug should be stopped if there is an increase in either:  
a. AST or ALT greater than or equal to 5-times the upper limit of normal at the local lab 
or for those with elevated AST and ALT at the time of enrollment an increase to 5-
times the level at enrollment   
b. AST or ALT to greater than or equal to 3-times the upper limit of normal at the local 
lab AND total bilirubin to greater than or equal to 2-times the upper limit of normal at 
the local lab. 
Elevated unconjugated (indirect) bilirubin in absence of other LFT abnormalities – continue study 
drug with frequent monitoring since isolated increase in unconjugated (indirect) bilirubin may be due 
to UGT1A1 inhibition. 
 
Outpatient monitoring: Patients discharged while on study drug with AST/ALT or bilirubin elevated 
> 2x the upper reference limits or up trending from most recent value (but less than the inpatient 
stopping criteria) AND patients discharged not on study drug with either AST or ALT at least 3-times 
the upper limit of normal or total bilirubin at least 2-times the upper limit of normal at the time of 
discharge will have the following study procedures performed:  
 
1) 
7 (+/-2) days post-hospital discharge a repeat measurement of AST, ALT and total bilirubin 
will be obtained.  
a. 
Patients NOT on study drug at the time of repeat LFT measurement:  
*If these repeat measurements are less than 3-times the upper limit of normal for AST or 
ALT and less than 2-times the upper limit of normal for total bilirubin, then no further study 
procedures will be performed related to LFT monitoring. 
*If these repeat measurements are greater than 3-times the upper limit of normal for AST or 
ALT or greater than 2-times the upper limit of normal for total bilirubin, then a repeat 
measurement of AST, ALT and total bilirubin should be obtained 7 (+/-2) days later. If the 
AST or ALT remain above 3-times the upper limit of normal or total bilirubin is above 2-times 
the upper limit of normal after this repeat testing 7 days later, LFTs should be monitored per 
standard of care by a provider or if no provider followed-up by the study team. 
b.  
Patients ON study drug at the time of repeat LFT measurement:  
*If these repeat LFT measurements are below the upper reference limit of normal continue 
study drug to completion and no recheck is needed. 
*If these measurements remain above the upper reference limit of normal for either AST, 
ALT or total bilirubin but do not meet inpatient stopping criteria (defined above), continue 
study drug and a repeat measurement of AST, ALT and total bilirubin should be obtained 7 
(+/-2) days later. If this repeat testing remains above the upper limit of normal for AST, ALT 
or bilirubin it should be monitored per standard care by a provider or if no provider followed-
up by the study team.  
*If study drug is stopped (per inpatient stopping rules above) repeat measurement of AST, 
ALT and total bilirubin should be obtained 7 (+/-2) days later. If this repeat testing remains 
above the upper limit of normal for AST, ALT or bilirubin it should be monitored per standard 
care by a provider or if no provider followed-up by the study team. 

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Once study drug is stopped for abnormal LFT values, the study drug will not be restarted.  
 
 
 
Diarrhea: If symptoms become severe (grade 3 or above) while the patient is hospitalized, 
temporarily stop study drug until symptoms resolve to mild (grade 1). When restarting, study drug 
dose should be reduced to 100 mg twice daily or matching placebo for the remainder of the study. 
Study drug should be stopped if diarrhea becomes severe in the outpatient setting. 
 
Neutropenia:  
If the absolute neutrophil count (ANC) decreases to less than 1.0x10^9/L, the study drug should be 
discontinued.  
• 
If the ANC returns to above 1.0x10^9/L, the study drug may be restarted. When restarting 
the study drug, the dose should be reduced to 100 mg twice daily or matching placebo for 
the remainder of the study.  

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• 
In patients who restart fostamatinib at 100 mg BID after neutropenia resolves within the 14-
day window, and labs are not rechecked during hospitalization, the team must either: 1) 
repeat CBC with differential within 7 days of discharge OR 2) not restart the medication if 
they are unable to repeat CBC with differential in this 7-day time frame. 
• 
A CBC with differential will be checked daily while the patient is in the hospital and on study 
drug. If the patient is discharged with an ANC < 1.0x10^9/L then a repeat CBC with 
differential will be performed within 7 days of hospital discharge and repeated weekly for 4 
weeks or until the ANC is >1.0x10^9/L. 
• 
If a patient is found to have an ANC <1.0x10^9/L as part of routine care after hospital 
discharge while still in the follow-up period, then a CBC with differential should be checked 
weekly for 4 weeks or until the ANC is >1.0x10^9/L. 
• 
Study drug is not restarted when the ANC remains <1.0x10^9/L Those who are discharged 
with a normal ANC require no further measurement after discharge.    
 
Medication Interactions: 
Patients will be monitored after randomization to ensure the following medications are not started 
during study treatment: Atazanavir, Certinib, Clarithromycin, Cobicistat and cobicistat-containing 
coformulations, Idelalisib, Indinavir, Itraconazole, Ketoconazole, Levoketoconazole, Lonafarnib, 
Lopinavir, Mifeprostone, Mibefradil,Nefazodone, Nelfinavir, Ombitasvir-paritaprevir-ritonavir plus 
dasabuvir, Posaconazole, Ribociclib, Ritonavir, Saquinavir, Telithromycin, Troleandomycin, 
Tucatinib, Voriconazole) from randomization to 21 days post-randomization. For a full list of 
CYP3A4 substrates, please reference this regularly updated list: https://drug-
interactions.medicine.iu.edu/MainTable.aspx.  
  
 
22.8 Fostamatinib Arm Logistics 
The use of fostamatinib for the proposed indication is investigational and the study will be 
conducted under FDA IND #154000 and will cross reference IND #152131. Fostamatinib can be 
stored at room temperature, 20°C to 25°C (68°F to 77°F); excursions permitted between 15°C to 
30°C (59°F to 86°F). Rigel has adequate investigational product and placebo to enroll 300 active 
and 300 placebo patients.  
 
For regulatory reporting purposes, including identification and potential expedited reporting of 
‘SUSAR’ events, the following serious and/or non-serious Adverse Events/Reactions are among the 
events that are considered expected for this study: 
• 
Neutropenia 
• 
Diarrhea 
• 
Elevated AST, ALT, or bilirubin. However, AST or ALT greater than 10 times the local 
laboratory ULN or the baseline value at the time of randomization, whichever is greater, is 
considered unexpected for fostamatinib study drug for the purposes of adverse event 
reporting.  
• 
Hypertension  
 
 
The following is considered an AESI for the fostamatinib arm: 

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- 
AST or ALT greater than 5 times the local laboratory ULN or the baseline value at the time 
of randomization, whichever is greater  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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23 Appendix E. Non-NAT Tests Deemed with Equivalent Specificity to NAT by the Protocol Team 
Date EUA* Updated 
(first issued) 
Manufacturer 
Diagnostic 
(Letter of 
Authorization) 
PPA- Sensitivity 
NPA- Specificity 
Antigen 
Days since 
symptom 
onset 
13-Jan-2021  
(02-Jul-2020) 
Becton, Dickinson 
and Company (BD) 
BD Veritor System for 
Rapid Detection of 
SARS-CoV-2 
84% 
100% 
nucleocapsid 
5 
(11-Jan-2021)  
11-Jan-2021 
Ortho Clinical 
Diagnostics Inc. 
VITROS 
Immunodiagnostic 
Products SARS-CoV-2 
Antigen Reagent Pack 
90.0% 
(76.3–97.2%) 
100% 
(95% CI: 99.1–
100.0%) 
 
nucleocapsid 
7 
01-May-2021  
(01-May-2021) 
Quanterix 
Corporation 
Simoa SARS-CoV-2 N 
Protein Antigen Test 
97.7 % 
(95% CI: 92.03-99.72) 
100% 
(95% CI: 90.75-
100.0) 
nucleocapsid 
14 
23-Dec-2020  
(15-Dec-2020) 
Ellume Limited 
Ellume COVID-19 
Home Test 
95% 
[95% CI 82% - 99%] 
97% 
[95% CI 93% - 99%] 
nucleocapsid 
w/ or wo/ 
symptoms 
22-Dec-2020 
(18-Dec-2020) 
Quidel Corporation 
QuickVue SARS 
Antigen Test 
96.6% 
99.3% 
nucleocapsid 
5 
16-Dec-2020  
(26-Aug-2020) 
Abbott Diagnostics 
Scarborough, Inc. 
BinaxNOW COVID-19 
Ag Card 
84.6% 
(95% CI: 76.8% - 
90.6%) 
98.5% 
(95% CI: 96.6% - 
99.5%) 
 
nucleocapsid 
7 
16-Dec-2020 
(16-Dec-2020) 
Abbott Diagnostics 
Scarborough, Inc. 
BinaxNOW COVID-19 
Ag Card Home Test 
91.7% 
(95% CI: 73.0% - 
98.9%) 
100.0% 
(95% CI: 87.7% - 
100.0%) 
 
nucleocapsid 
7 
07-Dec-2020 
07-Dec-2020 
Luminostics, Inc. 
Clip COVID Rapid 
Antigen Test 
96.9% 
(95% CI: 83.8% - 
99.9%) 
100% 
(95% CI:    97.3% - 
100%) 
nucleocapsid 
7 
23-Oct-2020 
(23-Oct-2020) 
Celltrion USA, Inc. 
Sampinute COVID-19 
Antigen MIA 
 
 
99.4 % 
 
 
100% 
receptor binding 
domains 
(RBDs) spike 
proteins 
5 
13-Oct-2020 
(08-Oct-2020) 
Access Bio, Inc. 
CareStart COVID-19 
Antigen test 
88.4 % 
100% 
nucleocapsid 
5 
02-Oct-2020 
(02-Oct-2020) 
Quidel Corporation 
Sofia 2 Flu + SARS 
Antigen FIA 
95.2 % 
100% 
nucleocapsid 
5 
18-Aug-2020 
(18-Aug-2020) 
LumiraDx UK Ltd. 
LumiraDx SARS-CoV-
2 Ag Test 
97.6 % 
(91.6 % - 99.3 %) 
96.6 %  
(92.7 % - 98.4 %) 
nucleocapsid 
12 
17Jul 2020 
(08-May-2020) 
Quidel Corporation 
Sofia SARS Antigen 
FIA 
96.7 % 
(96.7% - 99.4 %) 
100 % 
(97.9 %- 100.0 %) 
nucleocapsid 
- 
 
 

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