An Adaptive, Randomized, doublE-blind, Placebo-controlled, Prospective, Pharmacological interVention Study In Participants With Long COVID-19 Syndrome: REVIVE-TOGETHER Trial
Phase: PHASE3
Conditions: Long COVID-19 Syndrome, Chronic Fatigue Syndrome
Sponsor: Cardresearch

 
 
 
Clinical Trial Protocol 
 
 REVIVE_TOGETHER  
 
“A Multicenter, Adaptive, Randomized, Double-Blind, Placebo-Controlled, Prospective Study 
of Pharmacological Interventions in Participants with Clinical Features Consistent with Long 
COVID-19: The REVIVE-TOGETHER Protocol” 
 
OFFICIAL STUDY TITLE :  A Multicenter, Adaptive, Randomized, doublE-blinded, Placebo-
controlled Study in Participants With Long COVID-19: The REVIVE 
Trial  
NCT06128967 
UNIQUE PROTOCOL ID - TOGETHER_REVIVE 
DOCUMENT TYPE -  Study Protocol 
English Translation of Original Portuguese Version 
PROTOCOL VERSION / AMENDMENT NUMBER:  
Version 2.0 – Amendment 1.0 
ORIGINAL PROTOCOL AMENDMENT DATE:  
 
11 April 2024 
DATE OF THIS ENGLISH TRANSLATION VERSION:  
07 April 2026 
SPONSOR / RESPONSIBLE PARTY: CARDRESEARCH – Cardiologia Assistencial e de 
Pesquisa LTDA 
ORIGINAL DOCUMENT LANGUAGE:  
 
 
Portuguese 
BRAZILIAN PROTOCOL UNIQUE IDENTIFIER (CAAE):  73272623.2.1001.5120 
IRB AMENDMENT APPROVAL LETTER NUMBER:  
6.762.896 
IRB AMENDMENT APPROVAL LETTER DATE:   
14 APRIL 2024 
 
STATEMENT 
This following document is an English translation of the original Portuguese study protocol. It is 
provided for public posting and informational purposes in ClinicalTrials.gov. The original Portuguese 
version remains the source document maintained by the sponsor/ investigator in accordance with 
applicable local regulatory, ethics, and institutional requirements in Brazil. 
CONFIDENTIALITY NOTE 
No research participant names or directly identifying personal information are included in this 
document. 

 
REVIVE_TOGETHER COVID Long-Term - Clinical Protocol 
 
              
    Clinical Protocol 
V2.0 – April 11, 2024  
 
Total pages: 123 
1 
 
Clinical Trial Protocol 
 
 REVIVE_TOGETHER 
 
 
 
“A 
Multicenter, 
Adaptive, 
Randomized, 
Double-Blind, 
Placebo-
Controlled, Prospective Study of Pharmacological Interventions in 
Participants with Clinical Features Consistent with Long COVID-19: The 
REVIVE-TOGETHER Protocol” 
 
Authors:  
Gilmar Reis, MD, PhD1,2  ; Leonardo Cançado Monteiro Savassi, MD, 
PhD1,2  ; Thiago Santiago Ferreira, MD1 ; Edward J Mills, PhD3  ; 
Lehana Thabane, PhD3  , Gordon H. Guyatt, MD3 . 
 
Document type  
Clinical trial protocol 
 
Study code  
REVIVE_TOGETHER_Brasil_ 
 
Registration number  None 
 
Version Number  
v2.0 (Amendment 1) 
 
Development phase  III (New indication) 
 
Version release date April 11, 2024 
 
1. Cardresearch - Cardiology Care and Research, Belo Horizonte, Brazil 
2. Pontifical Catholic University of Minas Gerais, Belo Horizonte, Brazil 
3. McMaster University, Hamilton, Canada 
 
 
All rights reserved  
May not be used, disclosed, published, or otherwise disseminated  
without the express consent of CARDRESEARCH 
 
 

 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
2 
OVERVIEW OF THE PROTOCOL .................................................................................................................................. 9 
1 INTRODUCTION .................................................................................................................................................... 21 
1.1 
BACKGROUND ..................................................................................................................................................... 21 
1.2 
MECHANISMS OF INFECTIVITY ................................................................................................................................. 21 
1.3 
IMMUNE RESPONSE IN COVID-19 .......................................................................................................................... 22 
1.4 
SUPPRESSION OF NLRP3 INFLAMMASOME ACTIVATION ............................................................................................... 25 
1.5 
SUPPRESSION OF THE NLRP3 INFLAMMASOME VIA PHASE 2 INDUCTION ......................................................................... 25 
1.6 
THROMBOSIS, COAGULOPATHY, SEPSIS, AND GASTROINTESTINAL LESIONS ........................................................................ 27 
1.7 
THE LONG COVID PHENOMENON ........................................................................................................................... 28 
1.8 
DEFINITION OF LONG COVID ................................................................................................................................. 28 
1.9 
IMMUNE DYSREGULATION, INFLAMMATORY STORM, AND PERSISTENT INFLAMMATION ASSOCIATED WITH LONG COVID .......... 29 
1.10 
CLINICAL MANIFESTATIONS, SYMPTOMS, AND PATHOGENESIS ........................................................................................ 30 
1.11 
RISK FACTORS ...................................................................................................................................................... 31 
1.12 
DIAGNOSTIC TOOLS .............................................................................................................................................. 32 
1.13 
THERAPEUTIC POTENTIAL ....................................................................................................................................... 33 
1.14 
FLUVOXAMINE ..................................................................................................................................................... 34 
1.14.1 
ANTI-INFLAMMATORY EFFECTS VIA THE S1R - IRE  .................................................................................................. 34 
1.14.2 
ANTIVIRAL ACTION THROUGH EFFECTS ON LYSOSOMES, AUTOPHAGY, AND/OR ENDOCYTOSIS. .......................................... 35 
1.14.3 
ANTIVIRAL EFFECTS AND PREVENTION OF ORGAN DAMAGE THROUGH REGULATION OF THE ER/UPR STRESS RESPONSE. ........... 
 
 .................................................................................................................................................................... 35 
1.14.4 
ANTIPLATELET EFFECTS (COMMON TO ALL SSRIS) ................................................................................................... 36 
1.14.5 
ELEVATED MELATONIN LEVELS ............................................................................................................................ 36 
1.14.6 
STUDIES OF FLUVOXAMINE IN COVID-19 ............................................................................................................. 37 
1.14.7 
STUDIES OF FLUVOXAMINE IN COVID-19 ............................................................................................................. 38 
1.15 
METFORMIN AND COVID-19 ................................................................................................................................ 40 
1.15.1 
ELEVATED GLUCOSE IS ASSOCIATED WITH WORSE OUTCOMES IN COVID-19 ................................................................ 40 
1.15.2 
METFORMIN MAY REDUCE ENDOTHELIAL INJURY AND ITS COMPLICATIONS. .................................................................. 41 
1.15.3 
REDUCTION OF “NEUTROPHIL EXTRACELLULAR TRAPS” (NETS) .................................................................................. 41 
1.15.4 
METFORMIN AND ITS IMMUNOMODULATORY EFFECTS ............................................................................................. 41 
1.16 
METFORMIN AND LONG COVID ............................................................................................................................. 44 
 
2 
STUDY OBJECTIVES ......................................................................................................................................... 46 
2.1 OBJECTIVES/PRIMARY OUTCOME .................................................................................................................................... 46 
2.2 SECONDARY OBJECTIVES/OUTCOMES ............................................................................................................................... 46 
 
3 
RESEARCH DESIGN .......................................................................................................................................... 46 
3.1 
STUDY DESIGN ..................................................................................................................................................... 47 

 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
3 
3.2 
RATIONALE FOR THE STUDY DESIGN .......................................................................................................................... 48 
3.3 
RATIONALE FOR THE DOSE/REGIMEN, ROUTE OF ADMINISTRATION, AND DURATION OF TREATMENT ...................................... 49 
3.3.1 
FLUVOXAMINE ..................................................................................................................................................... 49 
3.3.2 
METFORMIN ....................................................................................................................................................... 49 
3.5 RATIONALE FOR THE TEST .............................................................................................................................................. 50 
 
4 
RESEARCH PLAN .............................................................................................................................................. 51 
4.1 
OVERALL STUDY DESIGN ......................................................................................................................................... 51 
4.1.1 
VISIT V1: SCREENING VISIT/BASELINE VISIT/RANDOMIZATION GENERAL STUDY DESIGN ...................................................... 51 
4.1.2 
TREATMENT PHASE (RANDOMIZATION) ..................................................................................................................... 52 
4.1.3 
DURATION OF STUDY PARTICIPATION ........................................................................................................................ 52 
 
5 
PARTICIPANT SELECTION AND WITHDRAWAL ................................................................................................. 54 
5.1 
NUMBER OF PARTICIPANTS ............................................................................................................................. 54 
5.2 
INCLUSION CRITERIA ........................................................................................................................................ 54 
5.3 
EXCLUSION CRITERIA ....................................................................................................................................... 54 
5.4 
INCLUSION CRITERIA ........................................................................................................................................ 56 
5.5 
DISCONTINUATION OF THE INVESTIGATIONAL PRODUCT OR REMOVAL OF PARTICIPANTS .......................... 56 
5.5.1 
Discontinuation of the investigational ........................................................................................................ 56 
5.5.2 
Withdrawal from the study ......................................................................................................................... 56 
5.5.2.1 
Withdrawal of informed consent ........................................................................................................... 56 
5.5.2.2 
Participant suspended by the study investigator ................................................................................... 57 
5.5.2.3 
Participants with early discontinuation of the study .............................................................................. 57 
 
6. 
STUDY TREATMENTS ....................................................................................................................................... 58 
6.1 
TREATMENT BLINDING .......................................................................................................................................... 58 
6.2 
DOSAGE FORM/ADMINISTRATION OF THE FORMULATION ............................................................................................. 59 
6.3 
DOSAGE AND ADMINISTRATION .............................................................................................................................. 59 
6.4 
SUPPLY OF THE INVESTIGATIONAL MEDICAL PRODUCT .................................................................................................. 59 
6.5 
ALLOCATION OF STUDY TREATMENT ......................................................................................................................... 59 
6.6 
DELIVERY, STORAGE, AND INVENTORY MANAGEMENT BY THE RESEARCH CENTER ............................................................... 60 
6.6.1 
Delivery by the study site ............................................................................................................................ 60 
6.6.2 
Storage ........................................................................................................................................................ 61 
6.6.3 
Accounting .................................................................................................................................................. 61 
6.7 
CHANGE IN MEDICATION DOSE ................................................................................................................................ 61 

 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
4 
6.7.1 
Adverse reactions during medication use ................................................................................................... 61 
6.7.2 
Routine care ................................................................................................................................................ 61 
6.8 
PROHIBITED THERAPY, SPECIAL CONSIDERATIONS, AND CONCOMITANT TREATMENT ........................................................... 62 
6.8.1 
Prohibited medications ............................................................................................................................... 62 
6.8.2 
Concomitant medications ........................................................................................................................... 62 
 
7. 
RISKS AND PRECAUTIONS ............................................................................................................................... 63 
7.1 
PRECAUTIONS ............................................................................................................................................. 63 
7.2 
ADVERSE REACTIONS .................................................................................................................................. 63 
7.2.1 
Fluvoxamine ................................................................................................................................................ 63 
7.2.2 
Metformin ................................................................................................................................................... 63 
 
8. 
STUDY PROCEDURES ....................................................................................................................................... 64 
8.1 
SCREENING PROCEDURES ........................................................................................................................... 64 
8.2 
BASELINE PROCEDURES / RANDOMIZATION ............................................................................................................... 64 
8.3 
PROCEDURES DURING PARTICIPANT FOLLOW-UP ....................................................................................................... 65 
8.4 
PROCEDURES FOR UNSCHEDULED VISITS .................................................................................................................... 66 
8.5 
PROCEDURES FOR EARLY TREATMENT DISCONTINUATION/STUDY WITHDRAWAL .............................................................. 66 
 
9 
STUDY EVALUATIONS AND PROCEDURES ........................................................................................................ 67 
9.1 
LABORATORY TESTS .................................................................................................................................... 67 
9.2 
VITAL SIGNS ................................................................................................................................................ 67 
9.3 
PHYSICAL EXAMINATION ............................................................................................................................ 67 
9.4 
RESULTS REPORTED BY PARTICIPANTS ....................................................................................................................... 67 
9.5 
COLLECTION OF ADDITIONAL DATA ........................................................................................................................... 68 
9.6 
CONTRACEPTION IN WOMEN OF CHILDBEARING POTENTIAL ........................................................................................... 68 
 
10 
EVALUATION, RECORDING, AND REPORTING OF ADVERSE EVENTS ............................................................. 69 
10.1 
DEFINITION OF ADVERSE EVENTS ............................................................................................................................. 69 
10.2 
ADVERSE EVENT REPORTING PERIOD ......................................................................................................................... 69 
10.3 
COLLECTION OF ADVERSE EVENTS ............................................................................................................................. 70 
10.4 
EVALUATION OF ADVERSE EVENTS ............................................................................................................................ 70 
10.4.1 
Intensity/severity .................................................................................................................................... 70 
10.4.2 
Causality and reporting .......................................................................................................................... 70 

 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
5 
10.4.3 
Categorization of results ......................................................................................................................... 71 
10.5 
RECORDING AND REPORTING .................................................................................................................................. 72 
10.5.1 
Persistent or recurrent adverse events ................................................................................................... 72 
10.5.2 
Diagnosis versus signs and symptoms .................................................................................................... 72 
10.5.3 
Pre-existing medical conditions .............................................................................................................. 73 
10.5.4 
Clinical laboratory tests .......................................................................................................................... 73 
10.5.5 
Abnormal vital signs and other abnormalities ........................................................................................ 74 
10.6 
ADVERSE DRUG REACTIONS AND REFERENCE SAFETY INFORMATION ................................................................................ 75 
10.6.1 
Adverse drug reactions ........................................................................................................................... 75 
10.6.2 
Safety reference information .................................................................................................................. 75 
10.7 
SERIOUS ADVERSE EVENT ....................................................................................................................................... 75 
10.7.1 
Definition of a serious adverse event ...................................................................................................... 75 
10.7.2 
Reporting of serious adverse events ....................................................................................................... 76 
10.7.3 
SUSARs .................................................................................................................................................... 78 
10.8 
SPECIAL SITUATIONS .............................................................................................................................................. 79 
10.8.1 
Definition of special situations ............................................................................................................................ 79 
10.8.2 
RECORDING AND REPORTING OF SPECIAL SITUATIONS .............................................................................................. 80 
10.8.3 
EXPOSURE DURING PREGNANCY AND BIRTH EVENTS ................................................................................................ 80 
10.8.3.1 
Definition of exposure during pregnancy and birth events ................................................................................. 80 
10.8.3.2 
Exposure during pregnancy and recording and reporting of birth events .......................................... 80 
 
11 
STUDY COMMITTEES ................................................................................................................................... 82 
11.1 
DATA MONITORING COMMITTEE (DMC) ................................................................................................................. 82 
11.2 
EVENT ADJUDICATION COMMITTEE .......................................................................................................................... 82 
 
12 
STATISTICAL CONSIDERATIONS ................................................................................................................... 83 
12.1 
STUDY DESIGN ..................................................................................................................................................... 83 
12.2 
RANDOMIZATION ................................................................................................................................................. 84 
12.3 
SAMPLE SIZE CALCULATION .................................................................................................................................... 84 
12.4 
STATISTICAL ANALYSIS AND REPORTING .................................................................................................................... 85 
12.5 
ANALYSIS OF PRIMARY AND SECONDARY OUTCOMES .................................................................................................... 86 
12.6 
SENSITIVITY ANALYSES ........................................................................................................................................... 86 
12.7 
SUBGROUP ANALYSES ............................................................................................................................................ 87 
12.8 
MISSING DATA ..................................................................................................................................................... 87 
12.9 
ANALYSIS POLICY FOR COMBINED STUDIES ................................................................................................................. 88 
12.11 SUMMARY TABLE OF SITE ANALYSES ............................................................................................................................. 89 
 
13 
ETHICAL CONSIDERATIONS OF THE STUDY .................................................................................................. 91 

 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
6 
13.1 
ETHICAL CONDUCT OF THE STUDY ............................................................................................................................ 91 
13.2 
INFORMED CONSENT ............................................................................................................................................. 91 
13.3 
RESEARCH ETHICS COMMITTEE (CEP) ...................................................................................................................... 92 
 
14 
QUALITY CONTROL AND QUALITY ASSURANCE ........................................................................................... 93 
14.1 
QUALITY MANAGEMENT: CRITICAL PROCESSES AND DATA ............................................................................................. 93 
 
15 
REPORTING AND DATA RECORDING ............................................................................................................ 94 
15.1 
SOURCE DOCUMENTATION ..................................................................................................................................... 94 
15.2 
MEDICAL RECORDS ............................................................................................................................................... 95 
15.3 
RECORD RETENTION .............................................................................................................................................. 96 
 
16 
PROCEDURES FOR PROTOCOL AMENDMENTS OR EARLY TERMINATION OF THE STUDY .............................. 96 
16.1 
PROTOCOL DEVIATION .......................................................................................................................................... 96 
16.2 
PROTOCOL AMENDMENTS ...................................................................................................................................... 97 
16.3 
STUDY TERMINATION ............................................................................................................................................ 97 
 
17 
PUBLICATION AND DATA SUBMISSION POLICY ........................................................................................... 98 
 
 
 
 
 
 
 
 

 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
7 
GLOSSARY OF TERMS 
Evaluation 
A procedure used to generate the data needed for the study 
Cohort 
A group of newly enrolled participants treated with a specific dose 
and regimen (i.e., treatment group) at the same time  
Control medication 
Any medication (an active drug or an inactive drug, such as a 
placebo) that is used as a comparator for the drug being tested in 
the study 
Drug dose 
The dose of the drug administered to the participant (daily or 
weekly total, etc.).  
Inclusion 
The point/time of entry into the study for which informed consent 
must be obtained (i.e., before initiating any procedure described 
in the protocol) 
Period 
A part of the study that serves a specific purpose. Typical periods 
include: selection/recruitment, washout period, treatment, and 
follow-up 
Investigational drug 
 
The drug whose properties are being tested in the study; this 
definition is consistent with US CRF 21, Section 312.3, and is 
synonymous with "new investigational drug" or "experimental 
medicinal product." 
Treatment under 
investigation 
All drugs whose properties are being tested in the study, as well 
as their associated control treatments. 
This includes any placebo, any active control, and also approved 
drugs used outside their approved indications/doses or tested in 
a fixed combination. 
The investigational treatment generally does not include 
concomitant background therapies specified by the protocol when 
these are standard treatments for that indication 
Drug number 
A unique identifier on the label of each package of the 
study/investigational drug in studies dispensing the drug using an 
IRT system 
Protocol 
A written record of all procedures to be followed in a study that 
describes all administrative, documentation, analytical, and 
clinical processes to be used in the study. 
Arm 
A single component of a study that contains different objectives or 
populations within a single study. Common parts of a study 
include: a single-dose part and a multiple-dose part, or a part 
involving participants with established disease and those with 
newly diagnosed disease. 

 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
8 
Period 
A subdivision of a crossover study 
Premature withdrawal of a 
participant/patient  
 
 
 
 
 
The point at which a participant leaves the study before the 
planned completion of all study treatment administrations and/or 
assessments; at this point, all study treatment administrations are 
discontinued and no further assessments are planned, unless the 
participant is followed up regarding disease progression and/or 
survival 
Randomization number 
A unique identifier assigned to each randomized participant, 
corresponding to a specific treatment arm assignment 
Study drug/treatment 
 
Any single drug or combination of drugs administered to the 
patient as part of the required study procedures; includes the 
investigational drug, active treatment periods (run-in), or 
background therapy 
Discontinuation of 
study/investigational 
treatment 
 
The point/time at which the participant permanently discontinues 
use of the study/investigational treatment for any reason; may or 
may not also be the point/time of the patient’s early withdrawal 
Participant number 
A number assigned to each patient included in the study 
Variable 
A measured value or an assessed response that is determined at 
a specific assessment and used in data analysis to evaluate the 
investigational drug in the study 

 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
9 
PROTOCOL OVERVIEW 
Protocol - Long COVID Chronic Fatigue  
Title: 
“A multicenter, adaptive, randomized, double-blind, placebo-controlled, 
prospective study of pharmacological interventions in participants with 
a clinical presentation consistent with Long COVID-19: The REVIVE-
TOGETHER Protocol” 
 
Abbreviated 
Title: 
Long COVID Chronic Fatigue Syndrome 
Investigational 
product: 
Metformin, Fluvoxamine 
Indication: 
Long COVID with chronic fatigue syndrome 
Phase: 
PHASE III – New indication 
Sponsor: 
CARDRESEARCH - Cardiology Care and Research, LLC  
Study code  
LONG-COVID_REVIVE_TOGETHER 
Principal 
Investigators:  
Gilmar Reis, Leonarco Cançado Monteiro Savassi, Edward J Mills, Lehana 
Thabane, Gordon H Guyatt 
Proposing 
institution:  
Cardresearch - Cardiology Care and Research, LLC 
Collaborating 
Researchers 
Scientists  
Ed. J. Mills, PhD.  
Lehana Thabane, PhD 
Gordon H Guyatt, MD 
 
Objectives: 
The primary objective is to compare metformin, fluvoxamine, and placebo for 
the mean Fatigue Severity Scale (FSS) score at 60 days after randomization. 
 The secondary objectives are: 
1. To compare metformin, fluvoxamine, and placebo for the mean FFS 
score 30 days after randomization.  
2. To compare metformin, fluvoxamine, and placebo for the mean FSS 
score 90 days after randomization.  
3. To compare metformin, fluvoxamine, and placebo regarding the mean 
difference in change in health-related quality of life (EQ-5D-5L) at 60 
days after randomization.   
4. Compare metformin, fluvoxamine, and placebo for the odds ratio of 
all-cause mortality at 60 days after randomization.   
5. Compare metformin, fluvoxamine, and placebo for the odds ratio of 
unexpected hospitalization from all causes at 60 days.   
6. To assess the safety of metformin and fluvoxamine in this population 
of participants. 
7. To assess the medium-term effects (90 and 180 days) of the 
investigational medical products on the chronic fatigue scale (FSS 
scale) and quality of life (EQ-5D-5L).  
Design: 
A multicenter, double-blind, adaptive, prospective, randomized, parallel-
group, placebo-controlled study evaluating metformin and fluvoxamine with a 
90-day follow-up after randomization. 
Inclusion 
Criteria 
Participants must meet all of the following criteria to be eligible for 
participation in this study:  

 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
10 
 
 
 
 
 
1. Age 18 years or older at the time of screening.  
2. Willing and able to provide written informed consent, or have a legal 
representative who can provide informed consent (when approved 
locally and nationally).  
3. A previous SARS-CoV-2 infection confirmed by the participant (e.g., 
reports having had a positive nucleic acid amplification test or a 
positive professional-use or self-test SARS-CoV-2 rapid antigen test). 
4. Participants with a clinical presentation consistent with LONG COVID 
according 
to 
international 
definitions:   
(www.nice.org.uk/guidance/ng188 
, 
https://www.who.int/publications/i/item/WHO-2019-nCoV-
Post_COVID-19_condition-Clinical_case_definition-2021.1), 
and 
fatigue symptoms with an average score of at least 03 on the Fatigue 
Scale (FSS); 
5. Have had the most recent episode of COVID-19 within 24 months of 
screening;  
6. Not currently hospitalized or in need of hospitalization, or having been 
hospitalized in an intensive care unit during the COVID-19 episode.  
7. Participants with the following vital signs: 
a. Heart rate between 55 and 100 bpm; 
b. Temperature below 38°C; 
c. Oxygen saturation ≥ 95%.  
8. Participants who are capable of becoming pregnant or whose partners 
are capable of becoming pregnant must agree to use appropriate 
contraceptive methods during the study and for up to 90 days of 
follow-up.  
9. Symptoms of fatigue cannot be attributed to another cause (in the 
researcher’s opinion).  
10. Willingness to follow all study procedures.  
  
Exclusion 
criteria  
Participants who meet any of the following criteria will not be eligible to 
participate in the study:   
1. Known acute SARS-CoV-2 infection; 
2. Inability to understand the content of the Informed Consent Form or to 
follow the study procedures; 
3. Known prior diagnosis of myalgic encephalomyelitis/chronic fatigue 
syndrome, unrelated to SARS-CoV-2 infection;   
4. Known pre-existing dysautonomia, unrelated to SARS-CoV-2 
infection; 
5. Diabetes mellitus (exclusion criterion for the Metformin and Metformin 
Placebo arms); 
6. Known history of creatinine clearance below 30 mL/min or on dialysis. 
7. Known stroke within the 3 months prior to screening; 
8. Known severe anemia, defined as < 8 g/dL;   
9. Body Mass Index (BMI) > 40. 
10. Known diagnosis of Lyme disease;  
11. Any use of illicit drugs other than marijuana within 30 days prior to 
informed consent;   

 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
11 
12. Pregnant women or women of childbearing age who do not agree to 
use an effective method of contraception for 90 days from the date of 
signing this consent form; 
13. Women who are breastfeeding; 
14. Expected hospitalization for elective surgical procedures lasting more 
than 48 hours; 
15. Contraindications for the METFORMIN arm 
a. Participants currently taking metformin; 
b. Participants with creatinine clearance < 30 ml/min, a history of 
KIDIGO IV, or currently undergoing dialysis. 
16. Contraindications for the FLUVOXAMINE arm 
a. Use of serotonin reuptake inhibitors (donepezil, fluoxetine, 
escitalopram, paroxetine); 
17. Current severe comorbid psychiatric disorder (e.g., clinical 
depression, anxiety, sleep disorder, eating disorder, substance 
abuse) that is uncontrolled and associated with significant symptoms 
or requiring the use of a medication contraindicated in this study; 
18. Clinical history of moderate to severe hepatic impairment or hepatic 
cirrhosis with a Child-Pugh score of C or higher; 
19. Clinical history of severe chronic lung disease with significant 
limitation of activities; 
20. Inability of the participant to provide informed consent or adhere to the 
procedures proposed in the study;    
21. Taking medications known to cause chronic fatigue as a side effect 
(except for participants with chronic cardiovascular disease who are 
on chronic beta-blocker therapy);  
22. Known hypersensitivity and/or intolerance to fluvoxamine or 
metformin; 
23. Any clinical condition that, in the investigator’s opinion, may preclude 
participation in this study. 
 
Primary 
and 
secondary 
outcomes: 
 
 
 
The primary outcome is a reduction in the FSS score of at least one standard 
deviation 60 days after randomization. 
  
The secondary outcomes are: 
1. The FFS score 30 days after randomization.  
2. The FFS score 90 days after randomization.  
3. HRQL, assessed using the EuroQol-5D-5L 60 days after 
randomization.  
4. All-cause mortality up to 60 days after randomization.  
5. Unexpected hospitalization from any cause up to 60 days after 
randomization.  
6. Safety and tolerability of the investigational products 
7. Adverse events experienced by participants during treatment 
Procedures 
 
 
 
Screening procedures  

 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
12 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Before any study-specific procedure, the participant will receive an 
explanation of all study procedures and must date and sign an informed 
consent form (ICF) approved by a Research Ethics Committee (REC). The 
screening visit will be conducted in person. The ICF may be provided in 
physical, paper form or via an electronic informed consent form, in 
accordance with the guidelines recommended by CONEP. 
 
Eligible participants will be identified during the clinical consultation. 
Participants identified as having a probable diagnosis of Long COVID will be 
invited to learn about the research project. If they express interest, they will 
be referred to a designated and trained research team member who will 
present the proposed research program, verify the criteria for diagnosing 
Long COVID, and, if the diagnosis is confirmed, present the Informed 
Consent Form (ICF), which will be provided in accordance with current 
regulatory standards for clinical research.  Research procedures will only 
begin if participants who express interest in participating in the research 
program sign the TCLE, which is the first step in the research process. During 
the screening visit, participants will receive a unique participant number, 
which will be generated during the registration of the screening visit in the 
IWRS.  
  
Female participants are initially screened to identify those who meet the 
eligibility criteria. After obtaining informed consent, participants of 
childbearing potential will be asked to take a pregnancy test. Participants will 
also be asked to complete the FSS to determine if they have a moderate 
score to qualify for participation.    
  
Screening Visit Procedures and Randomization  
The screening visit and randomization procedures should be performed 
immediately after confirming eligibility criteria and obtaining consent to 
participate in the study and may be performed during the same visit. The 
following procedures will be performed:  
1. Obtaining the TCLE; 
2. EQ-5D-5L questionnaire; 
3. FSS Scale (chronic fatigue) 
4. Verification of inclusion/exclusion criteria; 
5. Urinary pregnancy test for females of childbearing age; 
6. Registration in the IWRS; 
7. Demographic data;  
8. Medical history; 
9. Comorbidities and risk factors;  
10. Concomitant medications; 
11. Physical examination findings;  
12. Vital signs (including temperature, heart rate, respiratory rate, and 
oxygen saturation in room air);  
13. Details of your COVID-19 medical history; 
14. Randomization and administration of the first dose of the 
investigational product/placebo.  

 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
13 
15. Delivery of the investigational product/placebo and instructions 
regarding it.  
16. Instructions regarding subsequent visits.  
  
Investigational product 
Participants will receive the investigational products and instructions on 
dosing, which must be taken as directed for a period of 60 days. 
 
Follow-up procedures  
Follow-up visits will take place on days 7, 30, 60, 90, and 180 (± 7 days) after 
randomization. The visits on days 7, 30, 90, and 180 should preferably be 
conducted via telephone, telemedicine, or social media. The visit on day 60 
should preferably be conducted at the research center, but may also be 
conducted via telephone, telemedicine, or social media. Participants will be 
asked to complete the FSS and the EQ-5D-5L 30 days, 60 days, and 90 days 
after randomization. In addition, on days 30, 60, and 90, the local research 
team will verify the participant’s status and clinical outcomes (all-cause 
mortality and unplanned hospitalization). The research team will collect data 
on adherence to the experimental product and the placebo. The research 
team will also document concomitant medications. Participants will be 
monitored for adverse events and laboratory abnormalities at each visit.    
   
The above data will be collected directly from the participant, the participant’s 
medical record, or the healthcare professional(s) responsible for the 
participant’s care. If a participant is unable to return to the healthcare center 
for a follow-up visit, the research team may contact the participant and 
conduct the visit by telephone. Data may also be collected via valid methods 
of electronic communication.    
 
 
 
 
 
 
 
 
  
Study Committee 
The event adjudication committee is responsible for ensuring that the source 
documents supporting the study event/outcome are adequate and that the 
diagnosis of adverse events is correct and supported by supporting 
documentation. In the absence of such documentation, events will be 
reviewed in accordance with good research practices, and the information 
certified by the principal investigator at each center will be attached to the 
study file.  
 

 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
14 
The independent Data Monitoring Committee (DMC) has a predefined plan 
for statistical data analysis and research safety that was approved prior to the 
start of this clinical trial. The analyses follow good clinical practices, being 
conducted in a blinded manner with possible unblinding regarding the 
indicated study arms if the pre-specified criteria for such unblinding are met 
(see the committee’s composition in the document attached to the regulatory 
file).  
 
The steering committee has been in place since the start of the clinical trial, 
and its purpose is to ensure the scientific integrity of the study, as well as to 
oversee operational aspects for the proper conduct of the research.  
 
Sample Size 
The sample size is 1,500 participants, with 500 participants per treatment arm 
under evaluation, including the placebo arm, and its operational 
characteristics were confirmed through closed-form, analytical calculations, 
and numerical methods. The operational characteristics for the head-to-head 
comparison of the treatment arm versus the placebo arm in reducing the 
mean fatigue score measured by the Fatigue Severity Scale (1 to 9) on day 
60 are determined. For each head-to-head comparison against the placebo 
arm, the Type I error rate (alpha) is set at 0.025 (one-sided) using a Bayesian 
normal-normal model. For the planning of our study, we assumed a plausible 
standard deviation of 1.7, which was estimated from a recent study that 
evaluated the psychometric properties of the Fatigue Severity Scale in 
participants recovering from COVID-191 . 
  
With the proposed sample size of 1,500 participants (3 arms containing 500 
participants each), the study will have adequate statistical power to detect a 
clinically important treatment effect. A difference of 0.45 has been suggested 
as a minimally important difference (MID) on the Fatigue Severity Scale in 
population groups of participants with multiple sclerosis and chronic fatigue2 . 
Even with a 10% dropout rate, our estimated power to detect a difference of 
0.45 is above 90%.   
  
Interim analyses are planned upon reaching 25%, 50%, and 75% of the study 
population. The unblinded statistician advising the DMC will make 
recommendations based on the continuous evaluation of overall data and 
epidemiological data on Long COVID from Brazil and the state of Minas 
Gerais. We are continuously monitoring the literature for new findings relevant 
to chronic fatigue and to participants with Long COVID, and this protocol will 
be updated as needed based on relevant information and submitted to 
regulatory authorities for ethical review. 
    
Statistical 
Methods 
 
 
 
Overview 
 
 
Study design  
A phase III adaptive, randomized clinical trial to evaluate the efficacy and 
safety of new treatments and existing medications (new therapeutic 

 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
15 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
indications) in participants with symptoms of chronic fatigue from Long 
COVID-19 following resolution of acute COVID-19 infection.  
 
Internal pilot phase 
Phase to assess the feasibility of the study and address any issues that may 
arise, aiming to refine the trial, with a focus on identifying unforeseen 
feasibility problems and resolving them to improve the overall success of the 
research. In particular, we will evaluate issues related to recruitment, 
informed consent, availability and administration of medications, data 
collection and recording, and the safety and tolerability of the proposed 
interventions. There will be no analysis of clinical results at the end of this 
phase—since participants will be transferred to the main study and analyzed 
collectively. This will involve a blinded analysis of up to 10% of the target 
sample size, with an initial focus on the safety and tolerability of the IPs under 
evaluation. 
 
 
The main clinical study 
Full implementation of the clinical trial, with the primary clinical endpoint being 
a reduction in perceived fatigue on the Fatigue Severity Scale (FSS). This 
phase is an adaptive phase, with three interim analyses to evaluate 
therapeutic effects using the placebo arm as the baseline. The main 
adaptations include:  
 
i) 
Discard the placebo arm if there is strong evidence of benefit.  
ii) 
Discard active study arms that show statistically unfavorable 
results.  
iii) 
Partnering with study arms of common interest from other 
study platforms, with the goal of obtaining responses in less 
time compared to conducting the study in isolation.  
 
Randomization  
Participants will be randomly assigned to one of the study arms in an equal 
allocation (e.g., 1:1:1). Stratified permuted-block randomization will be used 
for this study. Randomization will be stratified by participating primary care 
facility with varying block sizes of participants.  

 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
16 
 
The analysis and reporting of results follow the CONSORT guidelines 
(www.consort-statement.org). The participant selection process and study 
flow will be summarized using a flow diagram. The results of the analysis of 
participants’ demographic data and baseline outcome variables (primary and 
secondary) will be summarized using descriptive summary measures: 
expressed as mean (standard deviation) or median (minimum–maximum) for 
continuous variables, as appropriate, and number (percentage) for 
categorical variables. We will adopt an intention-to-treat principle to analyze 
all results.   
  
Bayesian statistics is the standard statistical framework for this study. 
Statistical analyses of IPs are limited to concomitantly randomized controlled 
data. Sequential designs with Bayesian stopping rules are expected to be 
used to evaluate multiple IPs. Recruitment for an IP will be stopped before 
the maximum sample size using decision rules pre-specified in the statistical 
analysis plan (SAP). The maximum sample size and corresponding decision 
rules are determined a priori by dedicated statisticians and methodologists, 
who will remain blinded during the conduct of the study. The statistical 
analysis plan (SAP) was formulated to ensure that the expected one-sided 
Type I error is less than 0.025 for each treatment. We will also use multiple 
imputation to handle missing data. For all models, results will be expressed 
as the effect reported as the mean difference for continuous outcomes, odds 
ratios (OR) for binary outcomes, and hazard ratios (HR) for time-to-event 
outcomes, with their respective 95% confidence or credibility intervals.   
  
All analyses will be performed using the latest version of R at the time of 
analysis. A detailed analysis plan will be developed prior to database lock. 
Any relevant safety data specific to Brazil will be immediately reported to our 
group for appropriate regulatory action.  
 
The 90- and 180-day visits are post-study follow-up visits. The primary and 
secondary outcomes of the study are planned to be based on the D60 visit 
after randomization.  
 
  
Analysis of Primary and Secondary Outcomes  
To analyze the primary outcome of the mean fatigue score at day 60 
measured by the Fatigue Severity Scale, we will use the Bayesian normal-
normal model with non-informative prior distributions for the group means. 
This analysis will be adjusted for prespecified covariates. For all other 
continuous outcomes, we will use similar modeling approaches. For all binary 
outcomes, we will use logistic regression for analysis. The Cox proportional 
hazards model will be used for all time-to-event outcomes. All analyses of 
secondary outcomes will be exploratory in nature, without adjustment for 
alpha for multiple secondary analyses.  
  
Sensitivity Analyses  

 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
17 
We will perform several sensitivity analyses to assess the robustness of the 
results, particularly for the primary outcome. These include:   
1. Protocol analysis based only on participants who adhered to the 
protocol as described;   
2. concurrent risk analysis: this analysis will adjust for death as a 
competitive risk for any outcome;   
3. Missing data analysis: This analysis will assess the impact of missing 
data on the primary outcomes.   
4. We will also conduct sensitivity analyses to account for any 
unforeseen issues that arise during the study process and that may 
affect the main conclusions.  
  
Subgroup analyses  
We will conduct several subgroup analyses to assess the consistency of 
effects across subgroups of participants:  
1. Age—assumption that younger participants will benefit more than 
older ones.  
2. Gender—assumption that women will benefit more than men.  
3. Vaccination status—assumption that vaccinated individuals will 
benefit more than those who did not receive the vaccine. 
4. Comorbidities at screening - Our hypothesis is that participants 
without the clinical comorbidities described above will benefit more 
than those without these clinical data.   

18 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
Table1 : Flowchart of the procedure: Fluvoxamine, Metformin, and Placebo 
 
 
 
Screening and 
Baseline 
Day 1 
Day 07  
± 3 days 
Day 30  
± 7 days 
Day 60  
± 7 days 
Days 90, 180, EoT, or 
early termination 
± 7 days 
Review of initial eligibility criteria 
 X(1) 
 
 
 
 
Informed consent for screening  
X 
 
 
 
 
Pregnancy test 
X(2) 
 
 
 
 
Second review of eligibility criteria - Conclusion 
and FSS scoring 
X(3) 
 
 
 
 
Informed consent for participation 
X 
 
 
 
 
Demographic data 
X 
 
 
 
 
Medical history 
X 
 
 
 
 
Comorbidities and risk factors 
X 
 
 
 
 
Concomitant medications 
X 
X 
X 
X 
X 
Physical examination 
X 
 
 
 
 
Vital signs (temperature, heart rate, respiratory 
rate, oxygen saturation) 
X 
 
 
X 
 
COVID-19 medical history 
X 
 
 
 
 
Randomization 
X 
 
 
 
 
IP administration* 
X 
X 
X 
X 
 
IP Adherence 
X 
X 
X 
X 
 

19 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
Concomitant medications 
X 
X 
X 
X 
X 
Fatigue Severity Scale (FSS) 
X 
 
X 
X 
X 
Visual Analog Scale of Fatigue Intensity 
X 
 
X 
X 
X 
EQ-5D-5L 
X 
 
X 
X 
X 
X 
Hospitalization 
 
X 
X 
X 
X 
Mortality 
 
X 
X 
X 
X 
Adverse events (AE) 
 
X 
X 
X 
X 
 
*Fluvoxamine, metformin, and the corresponding placebo will be administered for 60 days s 
 
 
 
 
 
 
 
 
 
 
 
 

20 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 

21 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
1 INTRODUCTION 
 
1.1 Background 
In December 2019, a series of cases of unknown etiology with symptoms similar to those of 
viral pneumonia began to be reported in the city of Wuhan, in Hubei Province, China3 . These initial 
cases were reported among people linked to a local seafood market in Huanan (“wet market”)4 . 
Patients were hospitalized with this viral pneumonia, and bronchoalveolar lavage fluid samples were 
collected from three patients, from which a new coronavirus, named 2019-nCoV, was isolated. 
Evidence for the presence of this virus included its identification in the bronchoalveolar lavage fluid 
of three patients via genome sequencing, direct PCR, and culture. The disease likely caused by this 
CoV was named “novel coronavirus-infected pneumonia.” The complete genomes were submitted 
to GISAID. Phylogenetic analysis revealed that 2019-nCoV belonged to the genus betacoronavirus, 
which includes coronaviruses (SARS-CoV, SARS-like bat CoV, and others) discovered in humans, 
bats, and other wild animals3 .  
 
As the number of cases increased, on January 30, 2020, the outbreak was declared a Public 
Health Emergency of International Concern.  As of January 31, 2020, there were 9,826 confirmed 
cases of 2019-nCoV worldwide5 . On that same day, the first two cases of 2019-nCoV were reported 
in Italy, and both had a history of travel to the city of Wuhan, China. There were also confirmed cases 
in 18 other countries besides Italy, for a total of 19 countries outside of China5 .  
 
As of February 11, 2020, 43,103 cases had been confirmed (42,708 of them in China) and 
1,018 deaths had been reported.  On that same day, the World Health Organization (WHO), in 
collaboration with its departments (the World Organization for Animal Health and the Food and 
Agriculture Organization of the United Nations), named the disease COVID-19 (short for 
“coronavirus disease 2019”) 6 . On the same day, the Coronavirus Study Group (CSG) of the 
International Committee on Viral Taxonomy proposed naming the new coronavirus SARS-CoV-2 
(Severe Acute Respiratory Syndrome Coronavirus 2)7 . 
 
On March 11, 2020, the World Health Organization declared COVID-19 a global pandemic8,9 
. 
 
 
1.2 Mechanisms of Infectivity 

22 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
This global health emergency has intensified research efforts to better understand the 
pathogenesis, clinical manifestations, and outcomes of people affected by this new viral strain. It is 
known that the “spike proteins” of coronaviruses, including SARS-CoV-2, interact with Angiotensin-
Converting Enzyme 2 (ACE2) and type II transmembrane serine proteases to invade cells10,11 . Thus, 
cells expressing ACE2, including pneumocytes and ciliated lung cells of the tracheobronchial tree, 
cardiac endothelial cells, intestinal mucosal cells, and renal epithelial cells, may be affected, which 
could partly explain the multi-organ dysfunction observed in participants12 . Under physiological 
conditions, ACE2 acts as a natural antagonist of the renin-angiotensin-aldosterone system (RAAS) 
by degrading angiotensin II and thereby producing angiotensins 1–7, which limit the vasoconstrictive 
capacity of angiotensin I. Angiotensins 1 through 7 have protective pulmonary effects by attenuating 
the inflammatory response13 . In fact, as observed in recent SARS-CoV epidemics (SARS and 
MERS) and recently identified in genetic studies of SARS-CoV-2, the inhibition of ACE2 
transmembrane receptor expression resulting from viral infection occurs through their blockade by 
“spike proteins.” This abrupt reduction in ACE2 activity in lung cells is a critical factor in the resulting 
pulmonary complications, given its important inhibitory effect on pulmonary inflammatory mediators, 
thereby reducing pulmonary edema and the unwanted amplification of the inflammatory response 
resulting from COVID-197 .  
 
 
1.3 Immune Response in COVID-19 
In the early stage of SARS-CoV-2 infection, the immediate immune response triggered in 
response to the virus can effectively eliminate it14 . Stimulation of innate immune cells leads to the 
production of inflammatory mediators, which, together with the complement system, exert antiviral 
effects in the early stage15 . Viruses have evolved to employ various strategies to evade this innate 
immune response. For example, viruses can evade the complement system by removing antibody-
antigen complexes from cell surfaces, downregulating Fc receptor expression, or mimicking the 
regulatory component of the complement16,17 . Studies have shown that the replication efficiency of 
SARS-CoV-2 in releasing infectious viral particles and “deceiving” the innate immune response 
induced in human intestinal tissues is more intense than that of SARS-CoV infection18 .  
 
Elevated cytokine levels commonly occur in critically ill COVID-19 patients, including IL-6, IL-
2R, IL-10, and tumor necrosis factor-alpha 19  . Autopsy data revealed intense generalized 
inflammatory activation involving the gastrointestinal tract, with intense neutrophilic and reticular cell 
activity. Despite this inflammatory activation, cells infected with the SARS-CoV-2 virus were rarely 
identified, suggesting a maladaptive immune response (cytokine storm20 ). In these situations, the 

23 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
direct cytopathological effects of SARS-CoV-2 induce apoptosis (a highly inflammatory form of 
programmed cell death) and release cellular mediators that culminate in the amplification of the 
inflammatory cascade characterized by the secretion of pro-inflammatory cytokines and chemokines 
that attract monocytes, macrophages, and T cells, leading to extensive tissue damage21 . In these 
situations, macrophages frequently communicate with SARS-CoV-2 targets via chemokines and 
phagocytic signals22 . This inflammatory process can regulate ACE2 expression in macrophages, 
leading to an intense amplification of tissue damage23 . 
 
One of the potential catastrophic effects of SARS-CoV-2 infections is cytokine storms. In fact, 
concentrations of circulating pro-inflammatory factors, such as IL-1, IL-6, and TNF-α, are strongly 
associated with ICU admission and mortality in patients with COVID-19. Studies of the first pandemic 
coronavirus, SARS-CoV, have shown that viral proteins play an active role in the processing and 
release of two specific pro-inflammatory cytokines, IL-1β and IL-18, by increasing NF-κB 
transcriptional activity and promoting the formation of the NLRP3 inflammasome24 (Figure 10). 
 
 
Figure 4 - Regulation of the NLRP3 inflammasome by SARS-CoV infection and NAD+. Several proteins 
encoded by SARS-CoV promote NLRP3 inflammasome activity and the release of pro-inflammatory cytokines. 
ORF3a activates NF-κB through TRAF3-dependent ubiquitination, which facilitates ASC cluster formation and 

24 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
NLRP3 inflammasome assembly [86]. ORF3a also possesses transmembrane domains and ion channel 
activity that drives a K+ efflux [85]. Protein E is located in the ER-Golgi compartment and promotes Ca2+ efflux 
[87,88]. ORF8b interacts directly with NLRP3. All of these mechanisms activate the inflammasome [89]. Host 
cells SIRT1, SIRT2, and SIRT3 suppress the NLRP3 inflammasome [94-98]. SIRT1 deacetylates NF-κB, 
suppressing its activity, and reduces oxidative stress, thereby decreasing inflammasome activation. SIRT2 
deacetylates NLRP3. SIRT3 suppresses mitochondrial ROS production, thereby decreasing inflammasome 
activation. SIRT6 reduces inflammation through deacetylation of H3K9 in the promoters of NF-κB target genes 
[99]. PARPs promote the formation of antiviral SGs through ADP-ribosylation of SG components. 
Abbreviations: Ac, acetylation; ACE-2, angiotensin-converting enzyme 2; ASC, apoptosis-associated spot-like 
protein containing a caspase recruitment domain; Casp1, caspase-1; ER, endoplasmic reticulum; NF-κB, 
nuclear factor κB; NLRP3, NOD-, LRR-, and pyrin-domain-containing protein 3; ORF, open reading frame; 
SARS-CoV, severe acute respiratory syndrome coronavirus 1; SIRT, sirtuin; TRAF3, TNF receptor-associated 
factor 3; Ub, ubiquitination. 
 
 
SARS-CoV proteins that facilitate these processes include open reading frame (ORF) 3a, 
envelope (E) protein, and ORF8b25 . ORF3a mediates NF-κB activation through TRAF3-dependent 
ubiquitination of an NF-κB inhibitory subunit and mediates the formation of inflammasome ASC 
subunit aggregates, which accompanies NLRP3 inflammasome assembly in human cells. 
Furthermore, ORF3a possesses transmembrane domains and ion channel (IC) activity that drives 
K+ efflux, which further promotes NLRP3 inflammasome activation. In fact, IL-1β secretion was 
completely blocked when BMDMs, stimulated with lentiviruses expressing SARS-CoV ORF3a, were 
treated with K+-rich medium. The SARS-CoV E protein also promotes inflammasome activation 
through its intracellular activity; it forms lipid-protein channels in the endoplasmic reticulum (ER)-
Golgi intermediate compartment, and the resulting Ca2+ stimulates NLRP3 inflammasome 
activation. 
 
Like SARS-CoV, SARS-CoV-2 can also activate the inflammasome. Active NLRP3 
inflammasomes were found in peripheral blood mononuclear cells (PBMCs) and tissues from 
deceased COVID-19 patients following autopsy, along with higher concentrations of serum IL-18 
that correlated with the severity of COVID-19. SARS-CoV-2 can activate the inflammasome through 
mechanisms similar to those of SARS-CoV-26 .  
NAD+ may contribute to the resolution of inflammation and to limiting or preventing the effects 
of cytokine storms. In the presence of reduced NAD+ concentrations, there is an enhancement of 
cytokine and pro-inflammatory activation induced by SARS-CoV and SARS-CoV-2. Similarly, low 

25 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
NAD+ concentrations may exacerbate the severity of COVID-19; therefore, increasing levels of this 
metabolite in at-risk populations is a potential therapeutic strategy to prevent severe forms of COVID-
1927 .  
 
 
1.4 Suppression of NLRP3 inflammasome activation 
 
Inflammasomes are protein complexes that are activated in response to certain pro-
inflammatory signals and induce the auto-activation of caspase-1; this protease, in turn, cleaves pro-
interleukin-1β and pro-interleukin-18 to generate the active forms of these mediators, which exert a 
crucial pro-inflammatory and pro-apoptotic effect in many pathologies28,29 . Inflammasomes can also 
induce a type of cell death known as pyroptosis; this results from caspase-1-mediated cleavage of 
the Gasdermin-D protein, which subsequently forms a plasma transmembrane channel that allows 
the extracellular efflux of cytokines, such as interleukin-1β, and which can also induce edema and 
cell death30 . A variety of different types of inflammasomes have been characterized; these include 
the NLR subset (NLRP1, NLRP3, NAIP/NLRC4), as well as the AIM2 and IFI16 inflammasomes. 
Given that the NLRP3 inflammasome is closely associated with the uncontrolled activation of the 
inflammatory cascade in COVID-19, we will focus on this inflammasome. 
 
The NLRP3 inflammasome consists of the NLRP3 protein interacting with ASC and caspase-
1 proteins, along with several accessory proteins, including NEK731 . The formation of NLRP3 
inflammasomes typically requires a “priming” step, in which the activated transcription factor Nuclear 
Factor kappa beta (NF-kappaB) drives the increased expression of NLRP3 and pro-interleukin-1β 
and -18. Subsequent activation of NLRP3 inflammasomes, in which the NLRP3/ASC/caspase-1 
complex is formed, is typically triggered by oxidative stress, a drop in intracellular potassium, and/or 
lysosomal rupture, which releases cathepsins32,33 . The role of oxidative stress in triggering NLRP3 
inflammasome assembly is well characterized. This sequence requires an interaction between the 
thioredoxin-interacting protein (TXNIP) and NLRP334 ,35 . 
 
 
1.5 Suppression of the NLRP3 inflammasome via phase 2 induction  
Phase 2 inducers are agents that trigger increased expression of a wide range of antioxidant, 
detoxifying, and cytoprotective enzymes. Many of them do this by covalently interacting with the 
cysteine groups of Keap1, a protein that binds to the transcription factor Nrf2, retaining it in the 
cytoplasm and promoting its proteasomal degradation 36 , 37 . When phase 2 inducers—or their 

26 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
electrophilic metabolites—bind to Keap1, Nrf2 is released to migrate to the nucleus and promote the 
transcription of many cytoprotective enzymes, whose gene promoters contain antioxidant response 
elements capable of binding to Nrf2. Of fundamental importance to our discussion is the fact that 
phase 2 induction increases the expression of both thioredoxin and thioredoxin reductase, as well 
as glutathione peroxidase, which is capable of eliminating hydrogen peroxide38,39,40 . Phase 2 
nutraceutical inducers that have demonstrated significant clinical utility include lipoic acid, ferulic 
acid, melatonin, sulforaphane, and phycocyanobilin41,42,43,44 . 
 
 
In the early stages of SARS-CoV-2 infection, an appropriate immune response is initiated 
against the virus, as occurs against similar coronavirus infections such as SARS-CoV-1 and MERS-
CoV 45 , 46  . In a subset of participants, the course of the disease may progress to an 
immunodysregulated state characterized by systemic hyperinflammation (“cytokine storm 
syndrome”)47,48,49,50 . This state may manifest clinically as ARDS, shock, and multiple organ failure. 
The resulting mortality rate is equal to or greater than 50% in this population51,52 , making it essential 
to seek interventions that can effectively address this subgroup of patients. Current approaches are 
limited to immunosuppressive therapies, many of which are still experimental, in participants who 
have already developed advanced disease 53,54 . Disease-modifying therapies that address the 
underlying pathophysiology and prevent progression to the hyperinflammatory state will be essential 
to mitigate COVID-19-related morbidity and mortality at the population level52 . 
 
Biomarkers of advanced stages and poor outcomes in COVID-19 support immunopathology 
models and suggest potential intervention strategies. Absolute counts and relative proportions of 
immune cells and lymphocyte subsets are aberrant in COVID-19, especially in severe casesErro! 
Indicador não definido.,55(,)56, 57,58 ,59, 60 ,61 . Inflammatory cytokines, chemokines, and other markers of 
inflammation including IL-2, IL-6, IL-7, IL-8, soluble IL-2 receptor, interferon-γ-inducible protein 10, 
monocyte chemotactic protein 1, colony-stimulating factor for granulocytes, macrophage 
inflammatory protein 1-α, tumor necrosis factor-α, C-reactive protein, ferritin, and D-dimer, among 
others, are also elevated in severe casesErro! Indicador não definido.,Erro! Indicador não definido.,Erro! Indicador não 
definido.,Erro! Indicador não definido.(,)Erro! Indicador não definido.,Erro! Indicador não definido.,Erro! Indicador não definido.,Erro! Indicador 
não definido.,62,63,64,65 . IL-6 specifically differs between non-survivors and survivors and is predictive of 
COVID-19 severity and in-hospital mortalityErro! Indicador não definido.,Erro! Indicador não definido.,Erro! Indicador não 
definido. . The levels of these markers mirror those observed in the cytokine storm induced by SARS-
CoV-1 and MERS-CoV infection66,67,68,69 .  
 

27 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
The cytokine storm is associated with ARDS, the leading cause of mortality in SARS and 
MERS70,71 . COVID-19 cytokine profiles also resemble the state   of hyperinflammation seen in 
primary hemophagocytic lymphohistiocytosis (HLH), a hyperinflammatory syndrome caused by 
underlying defects in perforin signaling pathways, and macrophage activation syndrome (MAS) 
observed in a subset of participants with autoimmune rheumatic diseaseErro! Indicador não definido.,72,73,74,75 
. Furthermore, the profile of immune dysregulation in COVID-19 shares similarities with CRS seen 
as an adverse effect of cellular immunotherapies, including CAR-T cell therapy76,77,78,79 . 
 
Data from randomized controlled trials and retrospective case series of participants with 
severe or critical COVID-19 treated with tocilizumab or siltuximab suggest that inhibition of the IL-6 
signaling axis may be effectiveErro! Indicador não definido., 80  . However, preliminary findings from a 
randomized, double-blind, placebo-controlled trial of sarilumab in COVID-19 suggest that targeting 
the IL-6 signaling pathway in participants with advanced disease may not be  as  effective  as  
suggested  by  observational data81 . Although   immunosuppressive treatments likely play an 
important role in COVID-19Erro! Indicador não definido. , the considerable cost, limited availability, and 
potential for serious adverse events limit the application of biologic therapies targeting different 
cytokine axes in COVID-19. 
 
 
1.6 Thrombosis, coagulopathy, sepsis, and gastrointestinal lesions  
Some recent cases have reported acute diarrhea, bleeding, and acute mesenteric thrombosis 
in participants infected with the novel coronavirus 82,83 . According to a recent study, intestinal 
abnormalities were a common finding (31%) on abdominal imaging in participants with COVID-19, 
and participants who required laparotomy frequently presented with histological ischemia due to 
thrombosis of small blood vessels84 . The direct attack of SARS-CoV-2 on the vascular endothelial 
system eventually leads to a vicious cycle between sepsis and increased cytokine levels. Vascular 
damage associated with endothelial cells and the increase in circulating cytokines together lead to 
a state of blood hypercoagulability, thereby inducing the occurrence of intestinal coagulation 
disorders. 
 
Elevated levels of D-dimer and fibrinogen in many participants with COVID-19 may not only 
be a common cause of peripheral and pulmonary thrombosis, but also the primary cause of intestinal 
hypercoagulability and ischemic events85,86 . Among hospitalized participants with COVID-19, the 
proportion of participants with elevated D-dimer levels was as high as 47% 87 . Compared to 
participants with coagulopathy, the typical manifestation in participants with COVID-19 was an 

28 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
increase in D-dimer concentration and the induction of mononuclear cells through elevated IL-6, 
thereby expressing tissue factor, which in turn induces coagulation activation and thrombin 
generation. TNF-alpha and IL-1 are the main mediators that inhibit the endogenous anticoagulation 
pathway. 
 
 
1.7 The Long COVID Phenomenon 
 
Shortly after the onset of the global COVID-19 pandemic, reports emerged showing that 
some individuals infected with SARS-CoV-2 developed persistent symptoms and new health 
problems that arose long after the acute phase of infection and could not be explained by other 
factors88 . The community of researchers who first recognized and reported this new syndrome used 
the term “Long COVID-19” to describe the post-acute and chronic sequelae of SARS-CoV-2 
infection89 . Long COVID (sometimes called “post-acute sequelae of COVID-19”) is a multisystemic 
condition comprising often severe symptoms that follow infection with severe acute respiratory 
syndrome coronavirus 2 (SARS-CoV-2). 
Long COVID can affect people of all ages—children, young adults, and older adults—and across all 
genders, races, and ethnicities, regardless of baseline health status90 . It is important to note that 
this syndrome does not only affect participants who had severe COVID-19, but is also observed in 
individuals who were asymptomatic or mildly symptomatic during the acute phase of SARS-CoV-2 
infection.  
 
 
1.8 Definition of Long COVID 
Although there is still no formal clinical definition of this nosological entity, the findings 
attributed to this condition include persistent shortness of breath, sleep disturbances, hyperlipidemia, 
fatigue, gastroesophageal reflux disease (GERD), cough, muscle weakness, joint pain, 
thromboembolism, renal disorders, neurological deficits, and cardiopulmonary abnormalities91,92,93 . 
LONG COVID is distinguished from acute COVID-19 primarily by the timing of symptoms relative to 
the onset of the disease, with acute COVID-19 defined as symptoms persisting for up to four weeks 
after onset, and LONG COVID restricted to symptoms that persist or develop more than two months 
after the onset of symptoms. It is estimated that 10–15% of convalescent COVID-19 patients may 
develop Long COVID94 , with 40% of these individuals reporting that their symptoms significantly 
affect their ability to perform basic daily tasks. Given the high prevalence of this post-COVID-19 
clinical condition, Long COVID has become a major public health concern. 

29 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
Many clinical definitions have been proposed for the long-term, often permanent, sequelae 
of COVID-1995,96 . Using the Delphi methodology, involving scientists and participants from all 
regions of the world, the World Health Organization (WHO) defined Long COVID as a condition 
occurring in individuals with a history of probable or confirmed SARS-CoV-2 infection , which typically 
develops three months after the onset of symptoms, persists for at least two months, and cannot be 
explained by alternative diagnoses97 . Symptoms may develop after initial recovery from acute 
SARS-CoV-2 infection or persist from the original illness, fluctuate, or even relapse over time, and 
generally affect daily functioning. 
A core outcome for clinical research has also been defined98 , encompassing 4 domains 
(physiological or clinical outcomes, life-impact outcomes, survival, and outcomes from previous 
endpoints), broken down into 11 endpoints: cardiovascular functioning, symptoms, and conditions; 
fatigue or exhaustion; pain; nervous system functioning, symptoms, and conditions; cognitive 
functioning, symptoms, and conditions; mental functioning, symptoms, and conditions; respiratory 
functioning, symptoms, and conditions; post-exercise symptoms and conditions; changes in work, 
occupation, and studies; survival; and recovery from previous outcomes. 
 
 
 
1.9 Immune dysregulation, inflammatory storm, and persistent inflammation associated with 
Long COVID 
 
There is growing evidence that LONG COVID is accompanied by dysregulated and persistent 
inflammation in multiple organs99,100,101 . Elevated serum levels of inflammatory biomarkers such as 
C-reactive protein, TNFα, IFNγ, and IL-6 were observed in convalescent COVID-19 participants 
who progressed to LONG COVID, with the intensity of these markers directly associated with the 
number of post-acute COVID-19 syndrome (PACS) symptoms reported by the patient. 
Phetsouphanh et al. described persistent immune dysfunction in individuals 8 months after mild 
COVID-19, characterized by detectable signatures of a highly activated innate immune system and 
elevated expression of both type I and type III interferons, as well as elevated concentrations of 
CXCL9, CXCL10, IL-8, and sTIM-3102 . It is postulated that this persistent inflammatory “scar” may 
drive tissue damage, endothelial dysfunction, hypoxia-induced tissue injury, and activation of 
pathogenic effector lymphocyte subsets 103 , 104  . A consistent finding associated with chronic 
inflammatory dysregulation has been the near-universal detection of elevated plasma levels of IFN-
γ and IL-2, suggesting that uncontrolled immune activation may contribute to the persistence of 
LONG COVID symptoms following the acute episode of viral infection. Similarly, this inflammatory 
activation is an indicator of endothelial dysfunction, which may be followed by vascular injury as a 

30 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
consequence of this production of circulating cytokines, generally released by activated CD8+ 
cytotoxic lymphocytes105 . 
 
In addition to triggering uncontrolled inflammation, it has also been suggested that both 
severe COVID-19 and LONG COVID are accompanied by the development of an auto-reactive 
immune response. The resulting production of autoantibodies can be documented through the 
development of humoral immunity against SARS-CoV-2106,107,108 . 
 
 
 
1.10 
Clinical manifestations, symptoms, and pathogenesis 
Long COVID generally manifests as fatigue and neurocognitive impairment (also known as “brain 
fog”); however, hundreds of biomedical findings have been documented, with many participants 
presenting dozens of symptoms across multiple organ systems (Figure1 )92 . Long COVID 
encompasses various adverse outcomes, with common conditions of recent onset including 
cardiovascular, thrombotic, and cerebrovascular diseases90 , type 2 diabetes89 , myalgic 
encephalomyelitis/chronic fatigue syndrome (ME/CFS)109 , and dysautonomia, particularly postural 
orthostatic tachycardia syndrome (POTS)110 . 
Symptoms can last for years111 and, particularly in cases of ME/CFS and recent-onset 
dysautonomia, are expected to be lifelong112 . With significant proportions of individuals with long 
COVID unable to return to work92 , the scale of new individuals with disabilities is contributing to 
labor shortages113 .  
There are likely to be several, potentially overlapping, causes of long COVID. Several 
hypotheses for its pathogenesis have been suggested, including persistent reservoirs of SARS-CoV-
2 in tissues 114 ; immune dysregulation 115 with or without reactivation of underlying pathogens, 
including herpesviruses such as Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV-6), among 
others116 ;impacts of SARS-CoV-2 on the microbiota, including the virome117 ; autoimmunity118 and 
immune system priming through molecular mimicry 119  ; microvascular blood coagulation with 
endothelial dysfunction120 ; and dysfunctional signaling in the brainstem and/or vagus nerve121 . 
 
 

31 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
Figure1 : Long COVID symptoms and their impacts on various organs with 
different pathologies 
 
 
 
1.11 
Risk Factors 
Potential risk factors include female gender, type 2 diabetes, EBV reactivation, the presence 
of specific autoantibodies118 , connective tissue disorders122 , attention-deficit/hyperactivity disorder, 
chronic urticaria, and allergic rhinitis123 , although up to 33% of individuals with long COVID have no 

32 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
identified pre-existing conditions. A higher prevalence of long COVID has been reported in certain 
ethnic groups, including people of Hispanic or Latino origin124 . Socioeconomic risk factors include 
lower income and an inability to rest adequately in the first few weeks after developing COVID-19125 
. Prior to the emergence of SARS-CoV-2, various viral and bacterial infections were known to cause 
post-infectious illnesses, such as ME/CFS126 , and there is evidence that long COVID may share 
their mechanistic and phenotypic characteristics127 . Furthermore, dysautonomia has been observed 
in other post-viral illnesses and is frequently observed in long COVID92 . 
 
 
1.12 
Diagnostic Tools 
Although diagnostic tools exist for some components of long COVID (e.g., tilt table tests for POTS128 
and MRI scans to detect cardiovascular involvement)129 , diagnostic tools for long COVID are, for 
the most part, still under development, including imaging tests to detect microclots130 , corneal 
microscopy to identify small fiber neuropathy88 , new QRS complex fragmentation on 
electrocardiograms as an indicator of cardiac injury, and the use of hyperpolarized MRI to detect 
abnormalities in pulmonary gas exchange131 .  Based on the tests offered as standard care, results 
for participants with long COVID are generally normal; many providers are unaware of symptom-
specific tests and diagnostic recommendations from the ME/CFS community. Early biomarker 
research suggests that levels of extracellular vesicles132  and/or immune markers indicating high 
cytotoxicity133 could be indicative of long COVID. Interestingly, dogs can identify individuals with long 
COVID based on sweat samples134 .  
Biomarker research in MS/CFS may also be applicable to long COVID, including electrical 
impedance blood tests, saliva tests, erythrocyte deformation, sex-specific plasma lipid profiles, and 
variables related to isocapnic buffering135 .  The importance of developing and validating biomarkers 
that can be used for the diagnosis of long COVID cannot be overstated—they will not only be useful 
for establishing the diagnosis but also for objectively defining treatment responses. 
Specific functional assessment tools can be applied according to the patient’s condition. The 
Patient-Reported Outcome Measurement Information System,38 the Post-COVID-19 Function Status 
Scale136 ,  and EuroQol-5D can be used to assess the functional status or quality of life of the patient. 
The modified Medical Research Council Dyspnea Scale137  can be used in participants with dyspnea. 
For neurological conditions, the Montreal Cognitive Assessment138 , Compasso 31139 , and the 
Neurobehavioral System Inventory140  are useful tools. For psychiatric conditions, the Generalized 
Anxiety Disorder 7, the Patient Health Questionnaire 9, the PTSD Symptom Scale, the Post-
Traumatic Stress Symptom Screening, the DSM-5 PTSD Checklist, the Revised Impact of Event 
Scale, the Hospital Anxiety Scale,  and the Depression Scale141 can be used.  

33 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
 
1.13 
Therapeutic Options 
Although there are currently no widely effective treatments for long COVID, treatments for specific 
symptoms have been effective for certain subgroups of the population. Many strategies used for 
MS/CFS are effective for individuals with long COVID, including stimulation124 and symptom-specific 
pharmacological options (e.g., β-blockers for POTS, low-dose naltrexone for neuroinflammation142 
and intravenous immunoglobulin for immune dysfunction) and non-pharmacological options 
(including increased salt intake for POTS, cognitive stimulation for cognitive dysfunction, and 
elimination diets for gastrointestinal symptoms)143 . Low-dose naltrexone has been used for many 
conditions, including MS/CFS, and has also shown promise in the treatment of long COVID143,144 . 
H1and H2antihistamines, often following protocols for mast cell activation syndrome and particularly 
involving famotidine, are used to relieve a wide range of symptoms. Another drug, BC007, has the 
potential to treat autoimmunity by neutralizing levels of G protein-coupled receptor autoantibodies145 
.  Anticoagulant regimens are a promising way to treat abnormal coagulation. In one study, symptom 
resolution was observed in all 24 participants who received triple anticoagulant therapy130,146 . 
Apheresis has also shown promise in alleviating prolonged COVID-19 symptoms; it has been 
theorized that it helps remove microclots and has been shown to reduce autoantibodies in 
ME/CFS147 .  However, it is quite expensive and its benefits are uncertain. Some supplements have 
shown promise in the treatment of long COVID and MS/CFS, including coenzyme Q10  and D-ribose, 
and may warrant further study148 . 
 
Pilot studies and case reports have revealed additional treatment options worth exploring. 
One case report noted the resolution of long COVID following treatment with the antiviral Paxlovid149 
, and a study investigating the treatment of acute COVID-19 with Paxlovid showed a 25% reduction 
in the incidence of long COVID150 . A small study of sulodexide in individuals with endothelial 
dysfunction observed a reduction in symptom severity151 . Pilot studies of probiotics have indicated 
potential for alleviating gastrointestinal and non-gastrointestinal symptoms152 .   An initial study found 
that Pycnogenol statistically significantly improved physiological measures (e.g., reduced oxidative 
stress) and quality of life (indicated by higher scores on the Karnofsky Performance Scale Index)153 
, consistent with the hypothesis based on success in other clinical studies. 
 
Taken together, current treatment options are based on small-scale pilot studies on long-haul 
COVID-19 or on what has been effective for other diseases; several other studies are ongoing154 .  

34 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
There is a wide range of potential treatment options for ME/CFS that encompass various 
mechanisms, including enhancing natural killer cell function, removing autoantibodies, 
immunosuppressants, antivirals for reactivated herpesviruses, antioxidants, mitochondrial support, 
and mitochondrial energy generation155 ;  most need to be clinically tested, which should occur 
urgently. Many newer treatment options remain under-explored, including anticoagulants and SARS-
CoV-2-specific antivirals, and the lack of funding is a significant limitation to conducting robust trials. 
 
 
1.14 
Fluvoxamine 
Fluvoxamine is a selective serotonin reuptake inhibitor (SSRI) and an S1R receptor agonist156 
. The rationale for considering the use of fluvoxamine in participants with COVID-19 is that S1R 
receptor agonists may attenuate excessive inflammation in participants with COVID-19. This and 
other potential mechanisms by which fluvoxamine may act in COVID-19 are summarized below. 
 
 
1.14.1 Anti-inflammatory effects via the S1R-IRE pathway 
S1R is an endoplasmic reticulum (ER) chaperone protein involved in many cellular functions, 
including the regulation of the ER stress response / unfolded protein response (UPR) and 
inflammation157 . The S1R protein has been shown to inhibit the inositol-requiring ER stress sensor 
enzyme 1α (IRE1) via XBP1-mediated splicing, a key regulator in cytokine production 158 . These anti-
inflammatory effects may be the most likely explanation for the beneficial effects of fluvoxamine. In 
COVID-19, an excessive inflammatory process known as a “cytokine storm” can contribute to the 
worsening of symptoms and cardiopulmonary complications, which can sometimes occur around the 
second week of the disease. Fluvoxamine may attenuate this excessive inflammatory response. 
 
In a 2019 study conducted by Rosen, fluvoxamine demonstrated benefits in preclinical 
models of inflammation and sepsis159 . In one model, mice were exposed to Toll-like receptor 4 (TLR4), 
lipopolysaccharide (LPS), which can trigger an inflammatory response. In another model, a fecal 
concentrate was injected, triggering an infection and an inflammatory response that is generally 
sublethal. Mice lacking S1R receptors showed excessive increases in cytokine levels and 
significantly reduced survival under either of these conditions, suggesting that these receptors inhibit 
the exacerbated inflammatory response. Non-genetically manipulated mice exposed to the same 
inflammatory triggers exhibited reduced cytokine levels and increased survival when treated with 
fluvoxamine (an S1R agonist). In investigating the mechanism underlying this effect, the authors 
demonstrated that S1 R receptors inhibit IRE1 activity, which in turn prevents excessive cytokine 

35 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
production. In an experiment using human peripheral blood, they also showed that fluvoxamine can 
reduce LPS-induced cytokine production by human cells. In the case of COVID-19, the S1R agonist 
action of fluvoxamine may have a similar ability to reduce the excessive inflammatory response 
induced by viral infection, thereby reducing inflammation-mediated organ damage. 
 
 
1.14.2 Antiviral action through effects on lysosomes, autophagy, and/or endocytosis. 
Coronaviruses utilize cathepsin-like proteases, present in the late endosome, to facilitate 
entry into the cell and remodel phagosomes and endoplasmic reticulum membranes, transforming 
them into sites of “viral replication”160,161 . Both processes require the stimulation of endocytosis and 
autophagy-phagosome-mediated pathways, followed by the termination of autophagy prior to 
lysosomal fusion. It has been demonstrated that the SARS-CoV-2 proteins Nsp6, Nsp2, Orf7b, and 
Orf9b localize to and modulate components of the autophagy pathway 162 , 163  . It has been 
demonstrated that Nsp6 additionally physically associates with S1R164 . Critically, S1R not only drives 
early-stage autophagy via the IRE1/UPR pathway, but is also essential for lysosomal fusion and for 
completing autophagy, likely by interacting with components of the SNARE complex165 . It is possible 
that activation of S1R by fluvoxamine may overcome Nsp6 inhibition of S1R to allow autophagy to 
eliminate SARS-CoV-2. Others have also recognized targeting the autophagy pathway as a 
promising strategy for treating SARS-CoV-2166,167 . 
 
Chemically, fluvoxamine is a cationic amphiphilic drug (CAD) with a log P of 3.1 and a pKa 
of 9.4, and, along with a variety of antipsychotic and antihistamine drugs, it accumulates 
preferentially in lysosomes. Perhaps because of this, fluvoxamine reaches higher concentrations in 
the lungs (which are rich in lysosomes) than in the brain168 . In the case of COVID-19, this may 
enhance the effects of treatment on the airway epithelium169 . At high doses (10 μM), CADs including 
fluvoxamine have been shown to inhibit lysosomal acid sphingomyelinase and cause drug-induced 
phospholipidosis. This nonspecific activity can globally disrupt lipid homeostasis, which in turn 
modulates autophagy via the mTOR nutrient sensing pathway170,171 . 
 
 
1.14.3 Antiviral effects and prevention of organ damage through regulation of the ER 
stress/UPR response. 
Some viruses hijack the ER stress/UPR response to achieve viral functions, and a series of 
studies have suggested that drugs targeting the ER stress/UPR response may be beneficial in the 
treatment of COVID-19172,173,174 . S1R agonists (such as fluvoxamine) regulate ER-associated stress. 

36 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
The effects of S1R ligands during ER-mediated stress and other ER functions may reduce organ 
dysfunction/damage175,176 . 
 
 
1.14.4 Antiplatelet effects (common to all SSRIs) 
Platelet hyperactivity may contribute to pathophysiological processes leading to thrombotic 
complications in COVID-19. SSRIs may inhibit platelet activation, which may reduce the risk of 
thrombosis, and these antiplatelet effects may be cardioprotective177,178 . 
 
 
1.14.5 Elevated melatonin levels  
The SARS-CoV-2 virus can activate the NLRP3 inflammasome, which may contribute to the 
cytokine storm179,180 . Melatonin may act on this NLRP3 pathway to reduce inflammation181,182 . 
Fluvoxamine inhibits melatonin metabolism, and therefore may increase melatonin levels in the 
body, which may be beneficial in COVID-19183 . 
 
A summary of the potential benefits of fluvoxamine use in COVID-19 was described by one of the 
researchers associated with this arm and is summarized in the figure below184 .  
 
 

37 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
Figure 7 – Potential mechanisms of benefit from the use of fluvoxamine in participants with COVID-
19184 . 
 
 
 
1.14.6 Studies of Fluvoxamine in COVID-19  
In a preliminary, randomized, double-blind study with a small number of adult outpatients 
with symptomatic COVID-19 and using an indirect clinical outcome, 80 participants treated with FLV, 
compared to 72 treated with placebo, had a lower probability of clinical deterioration over 15 days185 
. Participants were randomized within 7 days of symptom onset. These phase II data are striking, as 
none of the participants treated with fluvoxamine experienced clinical deterioration, whereas 8.3% 
of participants in the control group experienced such complications.  
 

38 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
We tested the hypothesis that fluvoxamine reduces clinical events during the pandemic 
(TOGETHER Clinical Trial; CAAE 41174620.0.1001.5120). We recruited 1,497 participants, with 741 
in the fluvoxamine arm and 756 in the placebo arm. The median age was 50 years (18–102) and the 
mean time to symptom onset was 3.4 days. The proportion of participants with the study’s primary 
outcomes was lower in the fluvoxamine group compared with the placebo group (79 [11%] of 741 
vs. 119 [16%] of 756); relative risk [RR] 0.68; 95% confidence interval in the Bayesian analysis [95% 
CI]: 0.52–0.88), with a probability of superiority of 99.8%, exceeding the pre-specified superiority 
threshold of 97.6% (risk difference: 5.0%). Considering the composite clinical outcome, 87% of 
events were hospitalizations and 12% were emergency department visits and observation > 6 hours 
associated with SpO2 < 94%. The calculations for the study’s primary outcome were similar in the 
modified intention-to-treat analysis (RR 0.69, 95% CI: 0.53–0.90) and higher in the per-protocol 
analysis (RR: 0.34; 95% CI: 0.21–0.54). There were 17 deaths in the fluvoxamine group and 25 
deaths in the placebo group in the primary intention-to-treat analysis (odds ratio [OR] 0.68; 95% CI: 
0.36–1.27). In the per-protocol analysis, considering only participants who adhered to both treatment 
arms for at least 7 days, we observed 1 death in the fluvoxamine group and 12 deaths in the placebo 
group (OR 0.09; 95% CI: 0.01–0.47)186 . 
 
In this same context, we also tested the combination of fluvoxamine and budesonide (100 
mg every 12 hours of fluvoxamine combined with 800 mcg every 12 hours of budesonide, both for 
10 days) in the TOGETHER clinical trial, involving 1,478 participants with COVID-19, with 738 
assigned to the treatment arm and 738 assigned to the placebo arm. There was a significant 
reduction in primary outcomes (hospitalization and/or days spent in the emergency department) in 
the treatment arm (1.8 [95% CI – 1.1 – 3.0] vs. 3.7 [95% CI – 2.5 – 5.3], relative risk 0.50 [95% CI 
0.25–0.92) with a probability of superiority > 98.7%187 .  
 
 
1.14.7 Studies of Fluvoxamine in COVID-19  
 
A retrospective evaluation conducted by the “National COVID Cohort Collaborative Group, 
National Institutes of Health, USA” assessed the correlation between the use of serotonin reuptake 
inhibitors (SSRIs) with S1R receptor agonistic activity and the incidence of Long COVID. A total of 
17,933 individuals were evaluated, including 14,484 who were not using SSRIs, 1,328 using SSRIs 
without S1R agonistic activity, and 2,021 participants using SSRIs with S1R agonistic activity. After 
the necessary statistical adjustments, a 26% reduction in the incidence of Long COVID was 
observed in participants who were using SSRIs with S1R agonistic activity188 .  
 

39 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
Sidky et al., from reference 188. 
 
 
 
Farahani et al. evaluated 100 participants with Long COVID symptoms using 100 mg of 
fluvoxamine every 12 hours for 3 months in a prospective, randomized, double-blind clinical trial189 . 
Various symptoms were assessed.  At the end of 3 months, data were obtained from 85 participants 
(15 were considered lost to follow-up). In the evaluated participants, a 48% reduction in fatigue-
related symptoms was identified.  
 
 

40 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
Farahani et al.: data regarding long COVID 
 
 
 
1.15 
Metformin and COVID-19  
Since the emergence of the first cases of viral pneumonia associated with SARS-CoV-2 to 
the present day, various clinical conditions have been definitively linked to the complications that 
have occurred, progression of lower respiratory tract infection, respiratory failure, and death. It is 
believed that these conditions allow the virus to trigger the development of an exacerbated 
inflammatory response. These clinical conditions are now considered risk factors for severe COVID-
19. Among these, advanced age is one of the most important, and associated with it are 
hypertension, diabetes, coronary artery disease, smoking, and obesity. In this context, obesity 
stands out, since after adjusting for other risk factors, obesity emerges as a significant factor 
associated with worsening respiratory status and the need for mechanical ventilation190 . Participants 
with a body mass index > 25 kg/m²or men with excess visceral adipose tissue are at high risk of 
requiring invasive ventilatory support during the course of COVID-19191 . 
 
 
1.15.1 Elevated glucose is associated with worse outcomes in COVID-19  

41 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
Metformin reduces blood glucose levels, but not below physiological levels, by reducing hepatic 
gluconeogenesis. Poorer glucose control has also been associated with higher mortality and end-
organ complications in participants with COVID-19192 . 
 
 
1.15.2 Metformin may reduce endothelial damage and its complications.  
It has been demonstrated that metformin improves microvascular endothelial function in women, 
perhaps due to a significant increase in the response to acetylcholine, a decrease in insulin 
resistance, and a non-significant decrease in tissue plasminogen activator, as previously 
demonstrated in an 8-week randomized controlled trial of metformin versus placebo in women with 
angina and normal coronary arteries193 . Pulmonary vascular endotheliosis was observed in the 
lungs of participants with COVID-19 194 .69 Acute endothelial inflammatory changes may be an 
important mechanism and a therapeutic target in mitigating the sequelae of COVID-19. Metformin 
reduces thrombosis in long-term follow-up, possibly by inhibiting platelet-activating factor and the 
release of mitochondrial DNA (mtDNA) 195 , and may be associated with better cardiovascular 
outcomes through mechanisms beyond glucose control. Coagulopathy and thrombosis associated 
with COVID-19 are a hallmark of the disease, and the pathophysiology is poorly understood. 
Furthermore, widespread micro- and macrovascular thrombosis has frequently been reported in 
autopsies of participants with COVID-19196 .  
 
 
1.15.3 Reduction of “neutrophil extracellular traps” (NETs) 
Metformin is associated with a significant reduction in neutrophil extracellular traps (NETs) and the 
neutrophil-to-lymphocyte ratio197 .  NETs are microbiocidal compounds containing DNA, histones, 
and proteins. Serum from participants with COVID-19 shows elevated levels of these histone and 
DNA components. It has been hypothesized that excessive NET formation leads to a cytokine 
storm and microthrombi (possibly independent of tissue factor), culminating in acute respiratory 
distress syndrome (ARDS) in COVID-19 198 .  Lymphopenia and neutrophil infiltration in the 
pulmonary capillaries have been an important feature of severe COVID-19199 .  Inhibition of NET 
release by metformin could therefore attenuate the development of downstream lung injury. 
 
 
1.15.4 Metformin and its immunomodulatory effects 
Visceral adipocytes secrete various pro-inflammatory mediators and procoagulant 
molecules, including interleukin (IL)-6, tumor necrosis factor α (TNF-α), adipokines, and D-dimer; 

42 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
participants with COVID-19 exhibit elevated production of inflammatory and procoagulant cytokines, 
which have been identified and associated with the pulmonary inflammatory condition in these 
participants200,201 . In participants with type 2 diabetes mellitus, TNF-α and IL-6 are elevated, and IL-
10 levels are reduced, with a direct relationship between these changes and the degree of insulin 
resistance observed in these participants202 .  
 
Metformin, a medication for type 2 diabetes, decreases levels of TNF-α, adipokines, and IL-
6, and increases levels of IL-10; these changes have been observed in both experimental studies 
and studies conducted in participants with type 2 diabetes and are more evident in women203,204,205 . 
These effects, associated with a reduction in circulating adipokines, may help minimize the degree 
of inflammatory response and thus reduce the severity of the disease206 .  
 
 
The activation of the AMPK/mTor/Stat3 pathway by metformin appears to prevent 
macrophages from undergoing classic pro-inflammatory activation that produces TNF/IL-6/IL-1β, 
cytokines that contribute to morbidity in COVID-19207, 208 . Possible evidence of this effect was 
observed in a retrospective study by Chen et al., which analyzed 904 participants with COVID-19 
and showed that metformin users had lower levels of IL-6 compared to non-users of metformin209 
. Metformin also inhibits toll-like receptor 7 (TLR7) signaling and interferon production, which 
appears to be important for the pathophysiology of COVID-19210, 211 . Metformin also inhibits IgE- 
and aryl hydrocarbon-mediated mast cell activation212 . Mast cell activation has been implicated as 
an early indicator of the inflammatory response to SARS-CoV-2 and, possibly, an indicator of an 
impending cytokine storm. It has been found that mast cells from female rats cause a greater 
increase in tumor necrosis factor alpha (TNF-alpha) than mast cells from male rats, which may 
explain the observational findings of reduced mortality in women taking metformin, but not in men 
taking metformin213 .  
 
Clinical studies have suggested that clinical complications and mortality in participants with 
COVID-19 may be lower in those taking metformin; however, the observational and retrospective 
nature of these studies (medical record analysis), as well as the fact that other studies have not 
confirmed this association, makes it difficult to adopt metformin as part of the treatment for 
hospitalized participants214,215,216,217 . A recent observational study identified metformin as a potential 
mortality reducer in women218 . 
 
Our research group evaluated the use of metformin in COVID-19219 . Between January 18, 
2021, and April 3, 2021, we evaluated 418 participants with early-stage COVID-19, with 215 

43 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
participants randomized to receive metformin (metformin XR 750 mg every 12 hours for 10 days) or 
a corresponding placebo. Recruitment took place in emergency departments and in dedicated acute 
respiratory syndrome emergency treatment units. On April 3, 2021, the Independent Data Safety 
Committee recommended discontinuing this arm due to futility, with a relative risk for primary 
outcomes of 1.14 (95% CI 0.73–1.81) and a probability of superiority of 0.28.  
 
 
 
 
Intent-to-treat analysis – Metformin in COVID-19, ref 204.  
 
 
Analysis of data related to symptoms on Day 60 post-randomization indicated a 26% 
reduction in symptoms of fatigue, dyspnea, and tiredness in the treated group (archived data, 
unpublished.  
 
 
Bramante et al. evaluated metformin in COVID-19 in a group of participants with COVID-19 
and mild symptoms220 . Between May 21, 2021, and February 14, 2022, 1,323 participants were 
recruited into the metformin group, in a factorial design (a subset of participants allocated to the 
metformin group also received fluvoxamine and ivermectin, with the same rationale applied to the 
metformin placebo group, resulting in an estimated 33% balance for each drug). Thus, 663 
participants were exposed to metformin and 660 participants were not exposed to metformin 
(considered the placebo- ). Recruitment occurred remotely via telephone contact with participants 
who tested positive for COVID-19. There were no in-person visits, and the primary outcome was 
clinical improvement on a symptom scale assessed 14 days after randomization. The adjusted rate 
of the primary outcome was 0.84 (95% confidence interval [CI], 0.66 to 1.09; P=0.19) for participants 
exposed to metformin, with no statistical significance.  
 
 

44 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
Symptom severity score in COVID-19, ref. 205. 
 
 
 
1.16 
Metformin and Long COVID  
 
Although clinical trials using metformin in participants with acute COVID-19 have not 
demonstrated efficacy in reducing clinically relevant events or symptoms, data suggest that 
prolonged use and/or prolonged follow-up of participants taking metformin may result in a lower 
incidence of dyspnea, fatigue, tiredness, and nonspecific neurological symptoms.  
 
 
Bramante et al. reported the results of a 10-month follow-up in their original clinical trial221 . 
The authors obtained data from 1,125 participants in a pre- follow-up specified as a secondary 
analysis of the original study, including 564 participants exposed to metformin and 561 participants 
not exposed to metformin. Assessments were conducted remotely via a questionnaire sent by email. 
Among participants randomized to the metformin arm, 6.2% (95% CI 4.2–8.2%) reported worsening 
symptoms after developing COVID-19, compared with 10.6% (95% CI 8.0–13.1%). The reduction in 
the risk of developing Long COVID in this population was estimated at 58% compared to the placebo 
group.   
 
 

45 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
Cumulative incidence of “Long COVID,” post-acute sequelae of SARS-CoV-2 infection 
(PASC), diagnosed by a physician more than 10 months after randomization. 
Adapted from ref 206. 
 
 
 
Although it shows a reduction of over 50% in the incidence rate of Long COVID compared to 
placebo, the clinical trial by Bramante et al. must be interpreted with caution. This data was collected 
remotely, without a standardized definition of Long COVID, as this diagnosis was reported by the 
attending physician at various clinics across the United States. Furthermore, the information was 
collected remotely, and data were missing for more than 6% of the original sample. The information 
was based on a proprietary scale, and participants were subsequently exposed to more than one 
potentially therapeutic agent.  
 
These limitations point to the need to seek evidence regarding a possible link between 
metformin and long COVID.  

46 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
2 STUDY OBJECTIVES 
 
The objective of this study is to evaluate the efficacy, safety, and benefits of using fluvoxamine and 
metformin in participants with a clinical diagnosis of long COVID who are being monitored at Primary 
Health Care Units in Brazil. The research subject’s participation in the protocol lasts up to 90 days, 
with an initial phase of up to 60 days considered the treatment phase and the period of up to 90 days 
considered the follow-up period for the study and verification of the study’s clinical results.  
 
 
2.1 Objectives/Primary Outcome 
The primary objective is to compare the use of Fluvoxamine and Metformin with placebo for the 
mean score on the Fatigue Severity Scale (FSS) on day 60 after randomization by at least 1 point. 
 
 
2.2 Secondary objectives/ outcomes  
The secondary objectives are:  
To compare fluvoxamine and metformin with placebo for the mean FFS score 30 days after 
randomization. 
To compare fluvoxamine and metformin with placebo for the mean FSS score 60 days after 
randomization. 
To compare fluvoxamine and metformin with placebo regarding the mean difference in the 
change in health-related quality of life (HRQL) as measured by the EQ-5D-5L at 60 days 
from randomization.  
Compare fluvoxamine and metformin with placebo for the odds ratio of all-cause mortality at 
60 days after randomization.  
Compare fluvoxamine plus metformin with placebo for the odds ratio of unexpected 
hospitalization from all causes at 60 days.  
To assess the safety of fluvoxamine and metformin in this population of participants. 
To evaluate the mid-term post-study effects (90 and 180 days) of the investigational 
medicinal products on the chronic fatigue scale (FSS scale) and quality of life (EQ-5D-
5L). 
 
 
 
3  RESEARCH PLAN  

47 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
3.1 Study Design 
This is a prospective, multicenter, adaptive, double-blind, randomized, placebo-controlled study to 
evaluate the effect of different therapies on reducing fatigue levels in participants with long-standing 
chronic fatigue syndrome. The treatment groups will be fluvoxamine, metformin, and the 
corresponding placebo. 
 
Participants will be randomized to one of the study arms using an independent, automated, 
iterative centralized randomization system (IVRS or IWRS).  The protocol includes an adaptive 
phase to accommodate any pre-specified modification needs.  
 
 
The protocol is designed to enroll 1,500 participants, with 500 participants in each study arm 
in an equal randomization ratio (e.g., 1:1:1). The protocol includes three planned interim analyses to 
occur at 25%, 50%, and 75% of the total number of participants. These interim analyses will allow 
for potential termination based on superiority, in the event of clear evidence of efficacy, or termination 
due to futility, in the event of insufficient evidence of efficacy. The decision thresholds for efficacy 
and futility are calibrated using statistical simulations to ensure control of the Type I error rate at 
0.025 in each of the pairwise comparisons between the experimental treatment arm and the control. 
These interim evaluations will be conducted by the Data Safety Committee, which will be supported 
by statisticians, and decisions will be communicated to the Steering Committee for appropriate 
regulatory action, when applicable. Any decision to discontinue treatment will be subject to 
immediate notification to regulatory authorities and the Ministry of Health, in accordance with current 
regulations. 

48 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
Research flowchart  
 
 
 
3.2 Rationale for the study design  
The COVID-19 pandemic has not only emphasized the importance of randomized clinical 
trials following proper methodology and adopting consistent practices in the planning, conduct, and 
analysis of the data obtained, but above all has demonstrated the need for the development and 
conduct of large-scale clinical trials, structured according to a master protocol, in a coordinated 
manner and through global collaboration222 . Therapeutic research for acute COVID-19 has resulted 
in futile efforts by most research groups, as, although thousands of trial records have emerged, most 
of them lack a consistent methodology, exhibit significant biases, and contain major flaws in their 
conduct and in the interpretation of results.  
Based on this perspective for long COVID-19, we proposed an adaptive platform study 
project, similar to the TOGETHER study conducted by our research group in several municipalities 
in the state of Minas Gerais and approved by this committee. Protocols with an adaptive design, 
through the “perpetual” study of more than one therapeutic intervention, can be evaluated and 
discarded (via a robust statistical analysis and evaluation plan) if they show no evidence of benefit223 
. These studies create opportunities to generate more efficient knowledge, which can be 

49 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
incorporated into routine clinical practice and promote continuous improvements. With their common 
platform and infrastructure, efficient use of control arms, and ability to expedite the launch of new 
study interventions, adaptive clinical trials can offer numerous advantages in identifying effective 
drugs and devices to combat COVID-19 and in comparative efficacy scenarios—quickly and 
efficiently, without compromising the quality of a randomized clinical trial224,225(,) 226 .  
 
 
3.3 Rationale for the dose/regimen, route of administration, and duration of treatment 
 
3.3.1 Fluvoxamine 
 
Fluvoxamine is an SSRI antidepressant with anti-inflammatory activity due to its S1R agonist 
effect. In the TOGETHER clinical trial, we administered a dose of 100 mg orally every 12 hours for 
10 consecutive days in patients with acute influenza-like illness. We used this dose in two arms: 
initially as monotherapy186 and subsequently in combination with budesonide187 , with tolerability and 
safety comparable to the placebo group. A dose of 50 mg administered orally every 12 hours was 
tested in some clinical trials but did not demonstrate efficacy, suggesting that a 50 mg dose every 
12 hours is insufficient to elicit anti-inflammatory effects via S1R receptors220,221 .  
 
The 60-day period is necessary because evidence suggests that Long COVID is related to a 
severe and persistent disruption of the immune-inflammatory balance, involving key pathways that 
require at least 3–4 weeks to restore equilibrium. Furthermore, clinical case reports using these 
drugs for a short period of time have failed to demonstrate benefits.  
 
 
 
3.3.2 Metformin 
 
Participants randomized to the metformin arm will receive a dose of 500 mg twice daily for a 
period of 60 days. We chose to modify the metformin dose in the clinical trial for two reasons: (1) To 
align with the international literature, which has used a 500 mg dose every 12 hours in clinical trials 
to evaluate Long COVID, and (2) following a blinded analysis of the first 100 recruited participants, 
where we identified a dropout rate due to mild adverse effects (diarrhea, abdominal pain, nausea) in 
9% of participants (common symptoms associated with the use of higher doses of metformin). In 
particular, the study by Bramante et al. observed a lower incidence of Long COVID in participants in 
the COVID OUT study’s Metformin Arm, where the dose used was 500 mg every 12 hours218 . There 
is evidence that doses exceeding 750 mg twice daily do not result in a better inflammatory profile. 
The metformin dose was selected based on previous observational evidence of a dose response at 

50 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
1,000 mg per day and is consistent with our previous TOGETHER study of metformin vs. placebo219 
and a similar study220 . We chose to use the extended-release formulation because it causes fewer 
gastrointestinal side effects and has more consistent and stable bioavailability, which is an 
advantage in providing a uniform serum dose. Since metformin is well tolerated over long periods227 
, to observe its potential effect in participants with prolonged COVID-19, we chose a 60-day duration, 
considering the pathogenesis of the immuno-inflammatory changes present in Long COVID, which 
often require a therapeutic action period of 3–4 weeks for the expected effects, this being a 
posspossible explanation for the futility of using metformin in acute forms of COVID-19.  
 
 
 
3.5 Rationale for the trial 
 
Currently, there are no approved therapies for the treatment of Long COVID. Given the 
complex disease process, high work disability, and persistent symptoms associated with the 
condition, evidence is needed to support the safety and efficacy of treatments. 
 
 
Few randomized studies of outpatient treatment for COVID-19 have followed participants for 
a  long period after acute treatment to assess the effect of early treatments on the incidence of post-
COVID-19 conditions. Although the mechanism of action has not been fully elucidated, metformin is 
known to alter glucose metabolism and is being investigated as an antiviral agent, demonstrating in 
vitro and in vivo activity against SARS-CoV-2. Recent studies suggest that metformin may also serve 
as a therapeutic option for participants with long COVID-19221 . 
 
  

51 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
4 RESEARCH PLAN 
 
 
4.1  Study Design  
 
The study consists of an in-person screening and randomization visit, which will occur 
simultaneously, and visits conducted via in-person visits, telephone contact, and social media 
applications using video conferencing.  The following visit schedule will be implemented for the 
metformin and corresponding placebo arms (adjusted for treatment days according to the 
intervention arms): 
 
V1 (Day 1) - Screening, Baseline, Randomization (Start of treatment phase) 
V2 (Day 7) - Follow-up Visit / Tolerance to Investigational Medicinal Products 
V3 (Day 30) - Follow-up visit 
V4 (Day 60) - Follow-up visit (in-person visit recommended) 
V5 (Day 90) - Follow-up visit after completion of the investigational product 
V6 (Day 180) - Follow-up visit after completion of the investigational product 
 
The D90 and D180 visits are considered post-study visits. The objective of these visits is to 
evaluate late effects of the investigational medical products and the persistence of any 
therapeutic effect observed during the treatment phase. This phase is an open-label, 
post-study phase.  
 
 
4.1.1 Visit V1: Screening visit/baseline visit/randomization General study design  
Screening and the baseline visit (randomization) (Day 1) will take place in person at the participating 
research center. After providing informed consent for the screening process, potential participants 
will be asked to complete the FSS questionnaire. The questionnaire will be scored to determine 
whether the potential participant meets the moderate fatigue threshold. If the participant meets this 
threshold, as well as all other inclusion criteria and none of the exclusion criteria, they will be invited 
to participate in the study. 
 
After completing the above screening activities, the research team will obtain the participant’s 
informed consent to participate in the study. Participants who do not provide informed consent will 
be considered screening dropouts. 
 

52 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
The following items will be collected at the baseline visit: participant demographics, medical 
history, comorbidities, risk factors, concomitant medications, physical examination findings, vital 
signs (including temperature, heart rate, respiratory rate, and oxygen saturation in room air), and 
details of the participant’s COVID-19 medical history. 
 
4.1.2 Treatment Phase (Randomization) 
After all procedures for the baseline visit have been completed, all inclusion criteria have been 
verified, and it has been determined that the patient does not meet any exclusion criteria for the 
study, participants will be considered eligible for the treatment phase and then randomized to 
fluvoxamine, metformin, or placebo in a 1:1:1 ratio.  
 
This randomization process will be conducted centrally or via the IWRS system, and treatment 
kits identified by random numbers will be allocated. The kits will be provided in a manner that 
prevents any individual from identifying the study drug. Participants will begin the assigned treatment 
(fluvoxamine, metformin, or placebo). 
 
 
4.1.3 Post-treatment phase (post-study follow-up)  
This phase aims to monitor the medium-term effects of using the investigational medical products, 
with a primary focus on the chronic fatigue scale (FSS scale) and quality of life (EQ-5D-5L scale). 
 
 
4.1.4 Duration of Participation in the Study  
Participation for each eligible study participant includes a screening visit (Day 1), followed by 
the 60-day treatment phase. A post-treatment visit will be conducted 30 days after the end of the 
treatment phase. The first day of medication administration is at the time of randomization and before 
the participant is discharged from the facility where they were enrolled in the study. The study will 
continue into a follow-up phase after completion of the investigational product, with follow-up visits 
on Day 30 and Day 60, with the final visit occurring 90 days after the randomization date (30-day 
post-investigational product visit). Results will be evaluated on Days 30, 60, and 90 after 
randomization. 
 

53 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
A safety assessment visit will be conducted on Day 7 post-randomization to assess the 
tolerability of the interventions and check for possible adverse events or adverse reactions to the 
investigational medical product under evaluation. 
 
Participants who discontinue the investigational product prematurely will be invited to remain 
in the study to complete the remaining procedures and will receive standard care for the long-term 
treatment and follow-up of COVID-19. 
 

54 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
5 SELECTION AND WITHDRAWAL OF PARTICIPANTS 
 
 
5.1 Number of Participants 
For detailed information on the rationale for the sample size, see Section 12. 
 
5.2 Inclusion Criteria 
Participants must meet all of the following criteria to be eligible for participation in this study:  
1. Age 18 years or older at the time of screening.  
2. Willing and able to provide written informed consent, or have a legal representative who can 
provide informed consent (where approved locally and nationally).  
3. A previous confirmed case of SARS-CoV-2 infection (e.g., reports having had a positive 
nucleic acid amplification test or a positive professional-use or self-test SARS-CoV-2 rapid 
antigen test). 
4. Participants with clinical symptoms consistent with LONG COVID according to international 
definitions: 
 
 
(www.nice.org.uk/guidance/ng188 
, 
https://www.who.int/publications/i/item/WHO-2019-nCoV-Post_COVID-19_condition-
Clinical_case_definition-2021.1), and fatigue symptoms with an average score of at least 03 
on the Fatigue Severity Scale (FSS); 
5. Have a diagnosis of the most recent episode of COVID-19 within 24 months of the screening 
visit date. 
6. Not currently hospitalized or in need of hospitalization, or having been hospitalized in an 
intensive care unit during the COVID-19 episode.  
7. Participants with the following vital signs: 
a. Heart rate between 55 and 100 bpm; 
b. Temperature below 38°C; 
c. Oxygen saturation ≥ 95%.  
8. Participants who are capable of becoming pregnant or whose partners are capable of 
becoming pregnant must agree to use appropriate contraceptive methods during the study 
and for up to 90 days of follow-up.  
9. Symptoms of fatigue cannot be attributed to another cause (in the researcher’s opinion).  
10. Willingness to follow all study procedures.  
 
 
5.3 Exclusion Criteria 

55 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
Participants who meet any of the following criteria will not be eligible to participate in the study:  
1. Known acute SARS-CoV-2 infection; 
2. Inability to understand the content of the Informed Consent Form or to follow the study 
procedures; 
3. Known prior diagnosis of myalgic encephalomyelitis/chronic fatigue syndrome, unrelated to 
SARS-CoV-2 infection;   
4. Known pre-existing dysautonomia, unrelated to SARS-CoV-2 infection; 
5. Diabetes mellitus (exclusion criterion for the Metformin and Metformin Placebo arms); 
6. Known history of creatinine clearance below 30 ml/min or on dialysis; 
7. Known stroke within the 3 months prior to screening; 
8. Known severe anemia, defined as < 8 g/dL;   
9. Body Mass Index (BMI) > 40. 
10. Known diagnosis of Lyme disease;  
11. Any use of illicit drugs other than marijuana within 30 days prior to informed consent;   
12. Pregnant women or women of childbearing age who do not agree to use an effective method 
of contraception for 90 days from the date of signing this consent form; 
13. Women who are breastfeeding; 
14. Expected hospitalization for elective surgical procedures lasting more than 48 hours; 
15. Contraindications for the METFORMIN arm 
a. Participants currently taking metformin; 
b. Participants with creatinine clearance < 30 ml/min, a history of KIDIGO IV, or currently 
undergoing dialysis. 
16. Contraindications for the FLUVOXAMINE arm 
a. Use of serotonin reuptake inhibitors (donepezil, fluoxetine, escitalopram, paroxetine); 
17. Current severe comorbid psychiatric disorder (e.g., clinical depression, anxiety, sleep 
disorder, eating disorder, substance abuse) that is uncontrolled and associated with 
significant symptoms or requiring the use of a medication contraindicated in this study; 
18. Clinical history of moderate to severe hepatic impairment or hepatic cirrhosis with a Child-
Pugh score of C or higher; 
19. A clinical history of severe chronic lung disease with significant limitation of activities; 
20. Inability of the participant to provide informed consent or adhere to the procedures proposed 
in the study;    
21. Taking medications known to cause chronic fatigue as a side effect (except for participants 
with chronic cardiovascular disease who are on chronic beta-blocker therapy);  
22. Known hypersensitivity and/or intolerance to fluvoxamine or metformin; 

56 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
23. Any clinical condition that, in the investigator’s opinion, may preclude participation in this 
study. 
 
 
5.4 Inclusion Criteria 
Participants may be randomized if they meet the inclusion criteria and do not meet any exclusion 
criteria for the study.  
 
 
5.5 Discontinuation of the investigational product or removal of participants 
 
 
5.5.1 Discontinuation of the investig  
During the treatment phase of the study, the participant may discontinue the investigational product 
at any time and at their discretion. Similarly, the investigator may discontinue the investigational 
product whenever deemed necessary, whether due to an adverse event or to ensure patient safety.  
Participants who discontinue treatment with the investigational drug without apparent 
justification after randomization and before the conclusion of the study will be encouraged to resume 
the medication and continue in the study as usual. If the medication is discontinued, the participant 
will be offered the option to remain in the study for the collection of outcomes. These participants will 
be treated according to the standard of care determined by the investigator. 
 
 
 
 
5.5.2 Withdrawal from the Study 
 
5.5.2.1 Withdrawal of Informed Consent 
Within the provisions of informed consent and clinical judgment regarding participant safety, 
every effort should be made to ensure that participants complete the treatment phase and post-
treatment visits. Participants will be informed that they may withdraw from the study at any time. 
However, if a participant withdraws from the study, every effort will be made to determine the reasons 
why the participant withdrew their consent. Although participants are not required to provide a reason 
for withdrawing consent, the investigator will make every effort to understand these reasons, fully 
respecting the participant’s rights. The reasons for withdrawal of consent, when provided by the 

57 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
participant, will be recorded in the medical record, and the center will do everything possible to 
ensure that the participant completes the early termination procedures described. Every effort will 
be made to contact a participant who fails to attend and/or does not attend a study visit by telephone 
to ensure that the participant is in satisfactory health. 
 
A participant who wishes to withdraw consent for the use of investigational medical 
products may agree to: 
Provide information about their own health status by phone or other means until the date of 
the final study visit. 
Allow family physicians or family members to be contacted to provide information about the 
participant’s health status 
Allow for a final contact at the end of the study 
 
 
5.5.2.2 Participant suspended by the investigator of the Study  
The investigator and the designated team may use their medical judgment to terminate a 
participant’s enrollment in the study if they determine that the participant’s continued participation in 
the study could result in safety risks to the participant. The investigator must immediately inform the 
study’s medical monitor of plans for the early withdrawal of a participant from the study. Participants 
withdrawn by the investigators will also have the opportunity to consent to the three options 
described above. All participants withdrawn early from the study for any reason must complete the 
Early Study Termination procedures described and be monitored for safety after receiving the last 
dose of study medication. Randomized participants who are withdrawn from the study for any reason 
will not be replaced. 
 
 
 
5.5.2.3 Participants with early discontinuation 
For all participants who drop out or discontinue the study prematurely (including participants 
who withdraw their consent), survival information may be verified through a search of a public 
database at the end of the study. 
 
 
 
 

58 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6. STUDY TREATMENTS 
 
 
6.1 Treatment blinding 
To minimize the potential for bias during the treatment phase, treatment randomization 
information will be kept confidential by a non-blinded biostatistician and will not be disclosed to third 
parties until the study database is finalized for statistical analysis upon completion of recruitment 
and follow-up of the last scheduled patient. The study is blinded, and neither the patient nor the 
investigator, the research team, nor existing committees will have access to the contents of the vials, 
which are produced sealed and hermetically closed. Similarly, the sponsor and the designated 
person will not have access to the randomization data. Treatment vials will be distributed using codes 
maintained by an unblinded biostatistician not involved in the research. The Data Monitoring 
Committee (DMC) and the drug safety team will not have access to participant allocation during the 

59 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
interim assessments planned in the study, except in foreseeable situations (decision to discontinue 
any arm of the study, whether due to efficacy or futility, termination of the study, or for reasons of 
overall participant safety). 
The clinical trial supply management team will have access to general information on 
investigational products at the site level for the management of packaging and distribution activities, 
as well as for the supervision of investigational product inventory levels in drug warehouses and at 
study sites, but will not have access to the allocation codes for these products. 
 
 
6.2 Dosage Form/Administration 
Metformin will be provided to the participant in the form of 500 mg extended-release tablets 
for oral use. 
Fluvoxamine will be provided to the participant in the form of 100 mg tablets for oral use. 
 
 
6.3 Dosage and administration 
Participants assigned to the 500 mg extended-release metformin treatment group should 
take the medication every 12 hours for 60 days. 
Participants assigned to the 100 mg dose of fluvoxamine should take the medication every 12 hours 
for 60 days. 
 
 
6.4 Supply of the investigational medicinal product 
The investigational products will be provided to the participant at no cost, with instructions 
for use solely for the purpose of the research. Bottles of identical format will be provided, containing 
sufficient medication for use as scheduled. The patient must return the blister packs for accounting 
of the medications delivered.  
The medications used in the study will come from pharmaceutical manufacturers with 
commercial authorization for their production, already approved by ANVISA, or through imports 
authorized by ANVISA for specific use in this research protocol.  
 
 
 
6.5 Study Treatment Allocation 

60 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
Each eligible participant will be assigned to one of three treatment groups via an Internet-
based remote randomization system (IWRS), namely: metformin, fluvoxamine, or the corresponding 
placebo. 
After enrollment in the initial phase of the study, each participant will receive instructions on 
the appropriate dosage of the medications and individualized instructions on when to take them and 
other concomitant medications, after considering the participant’s current medication regimen. The 
participant will be instructed to follow the agreed-upon dosing instructions for the remainder of the 
study to encourage adherence. The investigator will determine whether the study medication 
administration instructions need to be changed at each scheduled telephone follow-up visit, and any 
changes will be communicated to the participant. 
Participants who qualify for the treatment phase will be randomized to receive the study 
products as allocated to one of the study arms.  
 
Participants will also be instructed to keep their empty/unused medication bottles, which will 
be collected by the research team on Day 60for assessment of compliance during the treatment phase. 
Participants will be instructed to return empty/unused medication blister packs in the containers in 
which they were originally provided.  
Adherence will be documented. Adherence will be assessed based on the number of 
prescribed medications, the duration of treatment, and the quantity of dispensed and returned 
medications (used and unused). Adherence as reported by the study participant will also be 
considered.  
 
Treatment adherence will be considered satisfactory if the participant has taken 80% of the 
prescribed dose for the study period.  
 
 
6.6 Delivery , storage, and accounting by the research center  
 
 
6.6.1 Delivery by the study site 
Once the study site has been approved to receive the study drug, it will receive an initial 
shipment of investigational medicinal products sufficient to treat 20 participants. The need for 
replenishment of the study drug will be assessed regularly, taking into account the number of 
enrolled participants, the number of participants currently being treated at the study site, and overall 
study participation. 
 

61 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
6.6.2 Storage 
The pharmacist or their representative will verify and confirm receipt of each shipment of 
medication. The medications will be shipped and stored at room temperature not exceeding 30°C 
and away from direct sunlight. All study medications will be stored in a secure location. No 
participants other than those included in this specific clinical trial should take the medications 
provided for this study. The medication provided for this study must not be used in any animal or 
laboratory research. 
 
6.6.3 Accounting 
All investigational products dispensed to participants must be accurately recorded in the 
investigational product inventory maintained at the study site by the study pharmacist or qualified 
representative. Participants must be instructed to return all investigational products dispensed to 
them (blister packs and containers, whether used or unused), which will be collected by the research 
team during follow-up visits. All used investigational product blister packs and containers will be 
retained on-site by the study pharmacist or qualified representative for verification by the study 
monitor. Verification of inventory and adherence to the investigational product for all investigat s will 
be performed by the study pharmacist or qualified representative at each scheduled study visit. 
 
 
 
6.7 Change in medication dose 
 
6.7.1 Adverse reactions during use of investigational products  
The study participant must contact the study team if they experience any adverse reaction 
they believe is associated with the investigational product. Similarly, the patient will be monitored 
daily via safety phone calls to check for the presence of unwanted symptoms, adverse reactions, 
and other signs or symptoms that may be present. The participant may be scheduled for an 
additional safety visit whenever the investigator deems it necessary, based on the information 
obtained during the telephone contact.  
The decision to temporarily discontinue the medication may be made at any time by the 
patient or the investigator. An attempt should be made to resume the investigational products 
whenever possible.  
 
 
6.7.2 Standard of Care 

62 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
During the treatment phase, all participants will receive standard of care in accordance with the 
recommendations of the guidelines.   
 
 
6.8 Prohibited therapy, special considerations, and concomitant treatment 
 
6.8.1 Prohibited medications 
During the study, the following medications will be prohibited while the patient is being treated 
with the study medications: 
 
Fluvoxamine Arm: Selective serotonin reuptake inhibitors (except sertraline) 
1. Metformin Arm: Metformin 
 
 
6.8.2 Concomitant medications 
Information regarding concomitant medications (prescription medications, over-the-counter 
medications, herbal and naturopathic medications, etc.) will be collected at the start of screening 
and at each follow-up visit.  
In general, participants should continue with the same medications and regimens they were 
taking at the time of study enrollment. The doses of these concomitant medications should be kept 
as stable as possible during the study. In general, medications that the investigator considers 
appropriate for the treatment of any intercurrent illness or preexisting condition that is not on the list 
of prohibited medications or that does not constitute an exclusion criterion for participation in this 
study will be permitted. 

63 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
7. RISKS AND PRECAUTIONS 
 
7.1 Precautions 
The investigator must be aware of the administration of investigational drugs in the following 
situations: 
• Depression or psychiatric conditions: These participants must be carefully 
evaluated, and participation may be permitted if there is no evidence of uncontrolled 
symptoms, worsening, or major depression. Participants with severe psychiatric 
conditions should not participate in this research program.  
• Participants should eat after taking the medications. It is not recommended to take 
them on an empty stomach or to fast immediately after taking the medications.  
• Participants with a history of seizures may participate if they have not occurred in the 
past 60 days and are stable and under pharmacological control.  
 
 
7.2 Adverse Reactions 
 
7.2.1 Fluvoxamine 
Most adverse reactions reported in clinical studies conducted with fluvoxamine are 
gastrointestinal symptoms, generally of mild intensity (nausea, dyspepsia, mild diarrhea, abdominal 
pain). Other adverse reactions: agitation, anxiety, insomnia, headache, anorexia, palpitations, 
hyperhidrosis, malaise, QT interval prolongation (QTcF ≥ 450 msec). Aside from gastrointestinal 
symptoms, the occurrence of other symptoms is uncommon in treatments lasting less than 30 days.  
 
7.2.2 Metformin 
Most adverse reactions reported in clinical studies conducted with metformin are self-limiting 
and resolve upon discontinuation of the medication or with non-pharmacological measures. 
Common reactions to metformin use include: heartburn, stomach pain, nausea or vomiting, 
bloating, gas, diarrhea, constipation, weight loss, headache, and an unpleasant metallic taste in 
the mouth. 

64 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
8. STUDY PROCEDURES 
 
8.1 Screening Procedures 
Before any specific study procedure, the participant will receive an explanation of all study 
procedures and must date and sign an informed consent form (ICF) approved by a Research Ethics 
Committee (REC). The screening visit will be conducted (1) at Primary Health Care Units / Outpatient 
Clinics. 
 
Eligible participants will be identified during the clinical consultation. Participants diagnosed 
with long COVID-19 will be invited to learn about the research project. If they express interest, they 
will be referred to a designated and trained research team member who will present the proposed 
research program and provide the Informed Consent Form (ICF), which will be presented in 
accordance with current regulatory standards for clinical research. Research procedures will only 
begin if participants express interest in participating in the research program and sign the ICF. During 
the screening visit, participants will receive a unique participant number, which will be generated 
during the registration of the screening visit in the IWRS. 
 
Participants are first screened to identify those who meet the eligibility criteria. When a 
participant meets all eligibility criteria, they begin the baseline visit phase. 
 
The participant signs the TCLE 
Review of eligibility criteria. 
Pregnancy test for women of childbearing age. 
Completion and scoring of the FSS. 
Other procedures scheduled for the visit. 
 
 
8.2 Day-1 procedures ation / randomization 
 
The procedures performed prior to administration of the investigational drug and 
randomization must be performed immediately after confirmation of eligibility criteria and obtaining 
informed consent for participation in the study. The following procedures will be performed during 
this visit: 
• 
Registration in the IWRS. 
• 
Participant demographic data. 

65 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
• 
Medical history, including elective surgical procedures scheduled within 60 days of 
randomization; 
• 
Comorbidities and risk factors. 
• 
Concomitant medications. 
• 
Physical examination findings. 
• 
Vital signs (including temperature, heart rate, respiratory rate, and oxygen saturation in room 
air). 
• 
Details of your medical history of COVID-19. 
• 
Randomization and administration of the first dose of the investigational product/placebo. 
• 
Dispensing of the investigational product/placebo and instructions regarding it. 
• 
Instructions regarding subsequent visits. 
Participants will receive their first dose of the investigational medical product (fluvoxamine, 
metformin, or corresponding placebo) at the research center before being discharged 
home. They will be instructed to take the medications twice daily for 60 days. 
  
 
8.3 Procedures during participant follow-up 
In-person follow-up visits will take place on days 7, 30, 60, 90, and 180, all at intervals of ± 5 
days, following randomization. Participants will be asked to complete the FSS and the EQ-5D-5L 30 
days, 60 days, and 90 days after randomization. Additionally, on days 7, 30, 60, and 90, the local 
research team will verify the participant’s status regarding the outcomes of all-cause mortality and 
unplanned hospitalization for all causes. The research team will collect data on adherence to the 
experimental product and the placebo (Days 7, 30, and 60). The research team will also document 
concomitant medications. Participants will be monitored for adverse events and laboratory 
abnormalities (if they have undergone tests) at each visit.   
During the post-study period (visits on days 90 and 180 after randomization), symptoms 
present at the Day 60 visit will be recorded, as well as new events and symptoms. The D90 and 
D180 questionnaires (FSS Scale and EQ-5D-5L) will be administered.  
 
The above data will be collected directly from the participant, from the participant’s medical 
record, or from the healthcare professional(s) responsible for treatment if it is impossible to collect 
the data directly from the participant. If a participant is unable to return to the health center for a 
follow-up visit, the research team may contact them and conduct the visit via telephone, social media, 
and/or telemedicine. Data may also be collected through valid electronic communication methods.  
 
 

66 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
8.4 Procedures for Unscheduled Visits 
An unscheduled visit may occur at the researcher’s discretion or due to the patient’s need 
and may take place during the treatment period up to the final study visit. During an unscheduled 
visit at any stage of the study, the following activities will be performed if conducted via telephone: 
 
• 
Assessment of the reason for the unscheduled visit and determination of the course of action. 
• 
Assessment of adverse events. 
• 
Documentation of concomitant medications. 
• 
Adherence to the investigational product/placebo.  
 
 
Any other study assessments may be performed at the investigator’s discretion during an 
unscheduled visit. In the event of clinical progression of complications expected for long 
COVID-19, related adverse events will be considered as expected for the clinical 
condition presented.  
 
 
8.5 Procedures for early discontinuation of treatment/study withdrawal 
For participants who withdraw prematurely from the study (before the Day 90 visit), the center 
must make every effort to ensure that the participant completes the follow-up visit, which must be 
conducted on the day of withdrawal or as soon as possible after withdrawal. The assessments 
conducted at the end-of-study visit must be the same as those for the Day 90 visit. 
Participation in the study implies agreement to the proposed post-study period, which 
consists of two visits (conducted via telephone, social media, or telemedicine), one to be conducted 
on Day90(30 days) and the other on Day180(120 days) after the end of the therapeutic intervention 
phase. 
 

67 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
9 
STUDY ASSESSMENTS AND PROCEDURES 
 
 
9.1 Laboratory Tests 
In women of childbearing age, a pregnancy test is planned, and the biological material to be 
used is urine or serum. Laboratory tests may be performed to investigate adverse events or changes 
for which the researcher deems laboratory evaluations necessary, always with the participant’s 
safety and well-being in mind.  
 
9.2 Vital signs 
The following vital signs data will be collected: 
Temperature 
Heart rate 
Respiratory rate 
Arterial oxygen saturation using a digital oximeter. 
Weight and height (reported by the patient) 
Respiratory rate will be measured by digital oximetry or physical examination (vital signs). 
 
9.3 Physical Examination  
The researcher will perform a brief physical assessment of the participant and document 
relevant findings in the participants’ medical records.   
 
9.4  -reported outcomes 
The patient-reported outcome questionnaires (FSS and EQ-5D-5L) will be completed by 
participants at each visit, always as the first activity of the visit. Study coordinators will review the 
participant’s responses immediately after the participant completes the questionnaires to ensure that 
all questions are answered. 
 
The FSS questionnaire is a validated 9-item scale that measures the severity of fatigue and 
its effect on an individual’s activities and lifestyle, using a 7-point Likert scale (1 = strongly disagree 
and 7 = strongly agree). The questionnaire asks the individual to rate the severity of fatigue over the 
past week. A low score indicates that the individual disagrees with the statement, and a high score 
indicates that the individual agrees with the statement. The response options selected for each of 
the 9 statements are summed, and the sum is divided by 9 (the number of questions) to obtain the 

68 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
final mean score. The minimum average score is 1, and the maximum average score is 7. A score 
below 4 indicates that participants are not experiencing clinically relevant fatigue, which is 
considered an exclusion criterion for participation in the study. The Fatigue Severity Scale is 
commonly used in participants diagnosed with arthritis, fibromyalgia, multiple sclerosis, chronic 
fatigue syndrome, Parkinson’s disease, stroke, and COVID-19. The validity and reliability of the 
questionnaire have been evaluated in different populations, including those studied following 
COVID-19.   
 
  
The EQ-5D-5L is used globally as a generic measure of health status. The EQ-5D-5L 
descriptive system includes five dimensions: mobility, self-care, usual activities, pain/discomfort, and 
anxiety/depression. Each dimension has five levels: no problems, slight problems, moderate 
problems, severe problems, and extreme problems. Participants are also asked about their health 
status by checking the box next to the most appropriate statement in each of the five dimensions. 
This results in a single-digit number that expresses the selected level for that dimension. The digits 
from the five dimensions can be combined into a 5-digit number that describes the patient’s health 
status. The EQ visual analog scale records the patient’s self-assessment of health on a vertical 
visual analog scale, where the endpoints are labeled “The best health you can imagine” and “The 
worst health you can imagine.” This can be used as a quantitative measure of health outcomes that 
reflect the patient’s own judgment. The EQ-5D-5L is widely validated, and its applicability is 
recommended by regulatory agencies (FDA, EMA, and ANVISA). 
 
9.5 Collection of Additional Data 
The research team will also collect data on adherence to the investigational medical product. 
The research team will also document concomitant medications. Participants will be monitored for 
adverse events and laboratory abnormalities in tests performed for other purposes at each visit.  
 
9.6 Contraception in women of childbearing potential 
For women of childbearing potential, a urine or serum pregnancy test will be performed at 
the screening visit. A pregnancy test will be performed on all women of childbearing potential 
(childbearing potential being defined in this protocol as at least one menstrual period occurring in 
the past 12 months in women aged 18 to 55 years). Any pregnancy s during the treatment phase of 
the study will be monitored until delivery to assess potential complications and adverse events.  

69 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
10 EVALUATION, RECORDING, AND REPORTING OF ADVERSE EVENTS 
 
10.1 
Definition of Adverse Events 
228An adverse event is any unfavorable medical occurrence experienced by a patient or clinical trial 
participant who has received a drug and that does not necessarily have a causal relationship with 
that treatment. Therefore, an ADE may be any unfavorable and unintended sign (including an 
abnormal laboratory finding), symptom, or illness temporarily related to the use of an (experimental) 
drug, whether or not it is related to the (experimental) drug. This includes:  
(1) Any new clinical condition, sign, or symptom, clinically significant physical examination 
abnormality, or newly diagnosed event occurring during the ADR reporting period, 
including signs or symptoms associated with an underlying condition that was not 
present prior to the ADR reporting period;  
(2) A preexisting condition that has worsened in severity or frequency or changed in character 
after the participant signed the RCT during the ADR reporting period; and  
(3) Complications that occur as a result of interventions required by the protocol. An ADE 
may arise from any use of the investigational drug (e.g., off-label use, use in combination 
with another drug) and from any route of administration, formulation, or dose, including 
an overdose. Any side effects, harm, toxicity, or hypersensitivity reactions that may occur 
in a participant in this clinical trial may also be considered AEs. 
 
For the purposes of this protocol, events that will not be considered AEs include: 
o Fluctuating signs or symptoms expected from a pre-existing medical condition (e.g., tremor 
in a participant with Parkinson’s disease; migraine episodes) that did not worsen in severity 
or frequency or change in character during the ADE reporting period; 
o Surgeries or medical procedures are not AEs; however, the clinical condition (new or 
worsened) that led to the surgery or medical procedure is the reported AE (e.g., for 
appendicitis resulting in an appendectomy, the appendicitis should be reported as the AE); 
o Overdose without clinical signs or symptoms. 
 
10.2 
Adverse Event Reporting Period 
AEs, including serious adverse events (SAEs), will be collected throughout the study period, 
from the time the participant signs the WIC until the EoS visit. All AEs still present at the time of study 
completion will be monitored by the investigator through contact with the participant until resolution 
or stabilization, or until the participant is lost to follow-up and can no longer be contacted. The 
outcome must be documented in the participant’s source documents. The investigator must report 

70 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
all SAEs that occur after the reporting period specified in the protocol if, in the investigator’s judgment, 
there is a reasonable possibility that the SAE is related to the investigational product or any study 
procedure. 
 
10.3 
Identification of Adverse Events 
If a participant reports an adverse event, it is the investigator’s responsibility to obtain 
sufficient information to assess causality. This may require additional laboratory tests, a physical 
examination, telephone contact, etc. 
To avoid bias in the collection of AEs, participants should be asked to answer a neutral 
question, such as “How are you feeling?” It is also important to ask the participant, in a non-leading 
manner, about changes in their health or use of concomitant medications since the last visit. This 
information should be collected prior to the assessments at all study visits. In addition, any 
symptoms/conditions reported during the assessments and considered clinically significant by the 
investigator will be evaluated as AEs. 
 
 
10.4 
Adverse Event Assessment 
 
10.4.1 Intensity/ Severity 
The medical assessment of intensity will be determined using the following definitions: 
Mild: The AE is easily tolerated and does not affect usual activities. 
Moderate: The AE affects daily activities, but the participant is still able to perform them. 
Severe: The AE is incapacitating, and the participant cannot work or perform their usual 
activities. 
 
A new event will be documented whenever the intensity of an event changes. It is important 
to note the distinctions between serious AEs and serious adverse events (SAEs). Severity is a 
classification of the intensity of a specific event (such as mild, moderate, severe); however, the event 
itself may be of relatively minor clinical importance (such as a severe headache).  
A SAE, however, is an AE that meets any of the specified regulatory criteria required for 
severity designation (for example, a headache may be severe [significantly affecting the participant’s 
usual functions], but would not be classified as severe unless it met any of the criteria for SAEs). 
 
 
10.4.2 Causality and Reporting 

71 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
The investigator will provide a causality assessment for all AEs using their best clinical 
judgment based on the available medical information regarding the event being reported. The 
causality assessment will be reevaluated as new information becomes available. If the investigator’s 
causality assessment is not reported, the event will be considered “related” until such information is 
received. Each investigator will assess the degree to which the ADR is related to the investigational 
drugs using the following definitions: 
 
Unrelated: There is no reasonable possibility that the investigational product caused or 
contributed to the ADE. 
• 
The event is related to an etiology other than the investigational drug, such as an 
underlying disease, study-unrelated procedures, concomitant medication, or the subject’s 
clinical condition. 
• 
The timing of the ADE is not reasonably related to the administration of the investigational 
drug. 
 
Related: There is a reasonable possibility that the investigational product caused or 
contributed to the AE. 
• 
There is no compatible temporal association between the event and the administration of 
the investigational drug. 
• 
Is there a biologically plausible mechanism by which the study treatment could have 
caused or contributed to the ADE? 
• 
The event improves or resolves after discontinuation of the study drug without the initiation 
of any specific treatment for the event (withdrawal from exposure) and/or the event recurs or 
worsens after reintroduction of the study therapy. 
• 
The event cannot reasonably be attributed to a concomitant or underlying disease or to 
other medications or procedures. 
 
For the purposes of causality assessment, “reasonable possibility” means that, based on the 
investigator’s medical judgment regarding the available information, there are facts or arguments 
suggesting a positive causal relationship. 
 
10.4.3 Categorization of Outcomes 

72 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
The outcome may be classified as: recovered/resolved (e.g., without sequelae); 
recovered/resolved with sequelae; not recovered/not resolved; fatal; or unknown (if follow-up is not 
possible). 
 
If the outcome of an AEFI is reported as recovered/resolved with sequelae, the investigator 
must specify the type of sequelae on the AEFI form. If the outcome of an AEFI is reported as 
unknown, the investigator must specify (on the AEFI form) the rationale for selecting “unknown.” 
 
"Fatal" must be recorded as an outcome when the AE results in death. The cause of death 
is required when known. If an autopsy was performed, an autopsy report must be provided. If an 
autopsy was not performed, a death certificate must be provided, if obtainable. Death will be reported 
as an outcome and not as an event. If more than one AEs is possibly related to the participant’s 
death, the outcome of death should be attributed to the AE that, in the investigator’s opinion, is the 
most plausible cause of death. All other ongoing AEs/AEGs should be recorded as 
unrecovered/unresolved at the time of death. 
 
 
10.5 
Recording and Reporting 
 
10.5.1 Persistent or recurrent adverse events 
AEs that persist continuously, without resolution, between clinical trial assessments should 
be recorded. A new event should be documented whenever the severity of an event changes. AEs 
that resolve and then recur should have each recurrence recorded separately in the medical record. 
 
10.5.2 Diagnosis versus signs and symptoms 
Whenever possible, the investigator should report a diagnosis rather than individual signs 
and symptoms or abnormal laboratory values. However, if a cluster of signs and/or symptoms cannot 
be clinically characterized as a single diagnosis or syndrome at the time of reporting, each individual 
event should be recorded in the medical record. If a diagnosis is established later, all previously 
reported AEs based on signs and symptoms should be canceled and replaced with an AE report 
based on that single diagnosis, with an onset date corresponding to the onset date of the first 
symptom of the eventual diagnosis. 
 

73 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
The investigator should use standard medical terminology/concepts and avoid colloquial 
terms and abbreviations. Only one AD term should be recorded in each event field in the medical 
record. 
 
10.5.3 Pre-existing clinical conditions 
A pre-existing condition is one that is present at the screening visit for this study. This 
condition must be recorded on the medical history form. A pre-existing condition should only be 
recorded as an AE if the frequency, severity, or nature worsens during the study. When recording 
these events in the AE clinical record, it is important to indicate the concept of change regarding the 
pre-existing condition, including applicable descriptors (e.g., “more frequent headaches”) 
 
10.5.4 Clinical Laboratory Tests 
Not every laboratory test with results outside the reference range qualifies as an AE. A 
laboratory test result should be reported as an AE if it meets any of the following criteria: 
• 
Be accompanied by clinical symptoms 
• 
Result in a change in the study treatment (e.g., modification of the dosage regimen, 
discontinuation of treatment, or discontinuation of the study) 
• 
Result in an unplanned medical intervention 
• 
Show a change in a parameter from a normal value to a pathological value or a further 
worsening of an already pathological value 
• 
be considered clinically significant in the investigator’s opinion 
 
It is the investigator’s responsibility to review all laboratory results. Medical and scientific 
judgment must be exercised to decide whether an isolated laboratory abnormality should be 
classified as an ADE. When evaluating such changes, the extent of the deviation from the reference 
range, the duration until return to the reference range—whether during continuous treatment or after 
discontinuation of treatment with the investigational product—and the range of variation of the 
respective parameter within its range must be taken into account. 
 
The researcher is responsible for determining the clinical significance of each abnormality. 
If pathological laboratory values are present at the end of the treatment phase that were not 
present at baseline, additional clinical or laboratory investigations must be conducted until the values 
return to the reference range or a plausible explanation (e.g., concomitant disease) for the 
pathological laboratory values is found. The investigator must decide, based on the above criteria 
and the participant’s clinical condition, whether a change in a laboratory parameter is clinically 

74 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
significant and therefore constitutes an ADE. If the investigator considers this ADE to be serious, it 
must be reported as a SAE. 
 
If a laboratory abnormality meeting the above criteria is a sign of a disease or syndrome, only 
the diagnosis should be recorded in the medical record. If a laboratory abnormality that meets the 
above criteria is not a sign of a disease or syndrome, the abnormality itself should be recorded in 
the medical record, along with a descriptor indicating whether the test result is above or below the 
normal range (e.g., “elevated potassium” rather than “abnormal potassium”). If the laboratory 
abnormality can be characterized by a precise clinical term according to standard definitions, the 
clinical term should be recorded as the AE, for example, hypercalcemia or hypoglycemia. The initial 
severity of the event should be recorded, and the severity should be updated at any time if the event 
worsens. 
 
All pathological laboratory values/findings diagnosed during the treatment period must be 
reviewed by the investigator to provide a final clinical assessment in light of the dynamics of the 
laboratory changes/abnormalities. 
 
 
10.5.5 Abnormal vital signs and other abnormalities 
Laboratory results, ECGs, vital signs, and other non-standard safety assessments will be 
considered AEs if they meet at least one of the following criteria: 
• 
They are associated with symptoms or result in a diagnosis (in which case, the 
symptom or diagnosis will be recorded as an ADR) 
• 
Lead to discontinuation of the investigational product 
• 
Require treatment or referral of the participant for additional off-protocol testing 
(retesting or titration are within the protocol procedures). 
 
It is the investigator’s responsibility to review all vital signs, ECGs, and other safety findings. 
Medical and scientific judgment should be exercised to decide whether an isolated laboratory 
abnormality should be classified as an AE. If a clinically significant abnormality is a sign of a disease 
or syndrome (e.g., high blood pressure), only the diagnosis (e.g., hypertension) should be recorded 
in the medical record. 
 

75 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
Observations regarding the same clinically significant laboratory abnormality between visits 
should not be recorded repeatedly, unless there are changes in the etiology. The initial severity of 
the event should be recorded, and the severity should be updated at any time if the event worsens. 
 
 
10.6 
Adverse drug reactions and reference safety information 
 
 
10.6.1 Adverse drug reaction 
An adverse drug reaction (ADR) is an undesirable and unintended response to a drug related 
to any administered dose. This definition implies a reasonable possibility of a causal relationship 
between the event and the investigational drug. This means that there are facts (evidence) or 
arguments suggesting a causal relationship. 
Given that the investigational drugs have been commercially approved by ANVISA for 
decades, in this study only adverse reactions not yet described in ANVISA’s drug dossier and 
assessed by the investigator as having a reasonable causal relationship with a drug (under 
investigation) will be considered ADRs.  
Thus, no reports of ADRs related to the drugs used in 
this study are expected. 
 
10.6.2 Safety Reference Information 
Basic safety information (RSI) forms the basis for assessing the predictability of an AEF for 
accelerated reports and annual safety reports, as well as for the safety monitoring of clinical trial 
participants by regulatory agencies (or ethics committees). In the context of this study, no ADR 
reports are expected, as potential adverse reactions are expected to already be described in the SIR 
for the investigational drugs ( , and ANVISA Drug Dossier, and the package insert for the drug 
registered with ANVISA), except in exceptional cases, for the investigational medical products in this 
study.  
 
 
10.7 
Serious adverse event 
 
10.7.1 Definition of a serious adverse event ( )  
A SAE is defined as any adverse medical event that, at any dose: 
Results in death 

76 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
Be life-threatening (the term “life-threatening” in the definition of severity refers to an event 
during which the participant was at risk of death; it does not refer to an event that 
hypothetically could have caused death if it had been more severe) 
Require hospital admission or prolongation of an existing hospitalization. Hospitalizations for 
elective surgery (i.e., a planned, non-emergency medical procedure), social 
hospitalizations, and hospitalizations lasting less than 24 hours are not considered SAEs 
Result in persistent or significant disability/impairment 
Be a congenital anomaly/birth defect 
Be a significant medical event (i.e., clinically significant) 
 
Medical and scientific judgment must be exercised to decide whether prompt reporting is 
appropriate in other situations, such as for medically significant events that may not be an immediate 
life-threatening event or result in death or hospitalization, but that may put the participant at risk or 
require intervention to prevent one of the other outcomes listed in the definition above. These events 
should also be considered serious. 
Any worsening of a pre-existing condition or any new condition that meets the above SAE 
criteria should be considered an SAE, and the investigator is encouraged to discuss with the study 
coordination any SAE for which the severity assessment is uncertain or questionable. 
 
The following situations are not considered SAEs: 
Elective or pre-planned surgery for a pre-existing condition that has not worsened 
Routine health evaluations requiring hospitalization not associated with a deteriorating 
clinical condition 
Social hospitalization (homelessness, family circumstances, etc.) 
Adverse reactions associated with the investigational drugs, which are expected for such 
drugs according to the drug dossier registered with ANVISA 
Results under investigation  
 
10.7.2 Reporting of serious adverse events 
The SAE reporting period begins when the consent form is signed by the participant. The 
SAE reporting period ends at the 90-day visit.  
The occurrence of an SAE must be reported immediately to the study monitoring committee 
within 24 hours of its notification via fax, email, or telephone. This includes all SAEs (regardless of 
their relationship to the study treatment). 
 

77 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
A death occurring during the study or reported to the investigator, whether considered 
treatment-related or not, must be reported to the study monitoring committee. 
 
Any SAE considered to have a causal relationship (e.g., related) with the investigational 
product and discovered by the investigator at any time after the study must be reported. The 
investigator must provide a rationale for the assessment of a causal relationship. All safety 
information obtained after the clinical database has been closed must be documented in the safety 
database, and the implications for handling the data in the clinical database must be evaluated on a 
case-by-case basis. 
 
The onset date of an SAE is defined as the date on which the signs/symptoms/diagnoses 
became serious (i.e., meet at least one of the severity criteria). If a participant experiences an AE 
and it progresses to an SAE, a new SAE must be recorded. The resolution date of the original AE 
must be the same as the onset date of the SAE. However, when the AE is resolved and the pre-
existing AE is still ongoing, this should be recorded as a new AE. The resolution date of an AE is 
defined as the time when symptoms disappear or when the event is considered chronic (e.g., 
sequelae) or stable and/or if the severity criteria are no longer applicable. 
 
The investigator must complete the EAS report form and verify the accuracy of the 
information recorded on the EAS pages against the source documents. The sponsor’s EAS report 
form must be completed in capital letters, using medical terminology, in English, and within the 
specified time limits. Any supporting documentation (e.g., hospital discharge summary, autopsy 
report/death certificate, etc.) must be submitted/transmitted with the SAE report form (attachment). 
The supporting information provided must not reveal the participant’s identity beyond the agreed-
upon study identifier. The investigator must ensure that the reported information is accurate and 
consistent. 
 
At a minimum, the following information must be provided at the time of creating the initial SAE 
report: 
• 
Study name and/or number 
• 
The participant’s number, age, and sex/gender 
• 
The description/exact wording of the event (including the onset date of the SAE, its 
outcome, and the reason it was considered serious) 
• 
Relationship to the investigational medical product (e.g., causality) 

78 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
• 
Dose of the investigational medical product (number of packages) and dates of 
administration 
• 
Action taken regarding the investigational medical product 
• 
Severity of the event 
• 
Name and address of the investigator 
• 
Name of the reporter (including center name or number and country) and, 
• 
Dated signature of the investigator or sub/co-investigator 
 
When using electronic methods for reporting SAEs, some of the information listed above may 
be generated by the electronic system. Since SAEs are also AEs, the information in the AE clinical 
record and the SAE form must be consistent. 
 
Follow-up information must be handled in the same manner and reported within the same 
timeframe as the initial SAE report. A safety contact sheet will be provided to the Investigator (before 
the first participant provides informed consent), detailing all applicable contact information for safety 
reporting. This contact sheet will be kept up to date, and any changes will be provided immediately 
to the Investigator. 
 
Whenever possible, the investigator should report a diagnosis rather than individual signs 
and symptoms or abnormal laboratory values. 
 In the event of a fatal outcome, the investigator should provide a working diagnosis (the 
event that caused the outcome, e.g., death due to fatal myocardial infarction) rather than reporting 
only the death; and an autopsy report should be provided when possible. If the cause of death 
becomes known later (e.g., after autopsy), this working diagnosis should be replaced by the 
established cause of death. 
 
All reported SAEs, regardless of their relationship to the investigational product, must be 
followed up until resolution or stabilization, or until the participant is lost to follow-up and can no 
longer be contacted. At the EoS visit, updates must be recorded and submitted. In circumstances 
where the investigator cannot contact the participant (or their relatives), the investigator must provide 
a written statement (recorded in the participant’s source documents) to the study steering committee, 
confirming that the participant is no longer being followed up. 
 
10.7.3 SUSARs 

79 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
A suspected unexpected serious adverse reaction (SUSAR) is defined as any serious and 
unexpected adverse drug reaction (ADR). 
For the purposes of this protocol, the occurrence of SUSARs is not expected, since the drugs 
were approved several years ago by ANVISA and have been used in hundreds of thousands of 
participants, and potential adverse reactions and/or idiosyncrasies are already well known to 
regulatory authorities.  
 
The sponsor or investigator must notify the ethics committee and regulatory authorities of all 
SUSARs and other types of AEs (if applicable) in accordance with local safety requirements. 
 
 
10.8 
Special Situations 
 
10.8.1 Definition of special situations 
The following situations are defined as special: 
Medication abuse: persistent or sporadic, intentional, and excessive use of the study 
medication by the participant (not for therapeutic purposes) 
Medication error: An unintentional error in the prescribing, dispensing, or administration of 
an investigational medicinal product (IMP) during the study. (A medication error is any 
preventable event that may cause or lead to the inappropriate use of the medication or 
harm to the patient while the medication is under the control of the healthcare 
professional or the patient). 
Medication misuse: Intentional and inappropriate use of an EFP by the participant for 
therapeutic purposes that does not conform to the dose, route of administration, and/or 
indication(s) specified in the protocol (e.g., the participant deliberately took the medication 
twice daily instead of once daily) 
Drug overdose: administration of an amount of the study drug equivalent to three times the 
maximum dose permitted by the protocol per administration or per day. 
Drug-drug interaction involving the study drug 
Unexpected therapeutic or clinical benefit from the use of the study medication 
 
Suspected AEs associated with medication errors or unauthorized use (e.g., overdose) must 
be reported and documented in the medical record.  
 

80 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
10.8.2 Recording and reporting of special situations 
All special situations must be documented in the participant’s source documents. If a special 
situation leads to a serious adverse event (SAE), the event must be reported immediately within 24 
hours of notification via fax, email, or telephone. 
 
 
10.8.3 Exposure during pregnancy and birth events 
 
10.8.3.1 
Definition of exposure during pregnancy and birth events 
Decades of experience with metformin use suggest that this medication should not be 
prescribed to pregnant   participants without a careful assessment of the risks and benefits of its use 
during this phase. Thus, pregnancy is not expected during the treatment phase, and women must 
use contraceptive methods to prevent pregnancy (if necessary, we will provide an effective 
contraceptive method for use during the medication period).    
When a female participant becomes pregnant during the study and has received study 
treatment, the pregnancy outcome must be monitored, and the safety of the mother and fetus must 
be assessed. Therefore, the outcome of all such pregnancies (including normal births) must be 
monitored and documented, even if the participant has been withdrawn from the study or the study 
has been terminated. 
A female participant must immediately inform the investigator if she becomes pregnant during 
the study. The investigator must counsel the participant and discuss the risks and benefits of 
continuing the study medication and advise the patient on follow-up until the child is born.  
The investigator is responsible for monitoring the participant and the pregnancy outcome and 
for reporting this information to the sponsor. Every effort should be made to collect information on 
the pregnancy outcome up to 90 days after delivery (or otherwise, as appropriate). 
 
 
10.8.3.2 
Exposure during pregnancy and recording and reporting of birth events 
Pregnancies must be reported throughout the study, including up to 4 weeks after the last 
dose of the study drug received. Pregnancy reporting includes exposure of the female partner of a 
male participant. Although pregnancy is not considered an AEFI, it must be reported within 24 hours 
of notification by the participant. Pregnancy complications are reported as AEs or SAEs (if 
applicable). All pregnancies will be followed through delivery to record any SAEs. Deaths, 
spontaneous or elective abortions, congenital anomalies/birth defects, and AEs/SAEs occurring in 
newborns must be reported as SAEs. Newborns potentially exposed to the study drug through 

81 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
maternal or paternal sources who present with an AEFI before, during, or after delivery (including 
those who were breastfed by the participating mother) will be followed up until the event is resolved 
(or for a period of 1 year). 

82 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
11 STUDY COMMITTEES 
 
 
11.1 
Data Monitoring Committee (DMC) 
An independent DMC will be established, composed of scientists of good reputation and experience, 
with no involvement in this research protocol. The DMC will act as a research advisor to monitor the 
safety of participants in this study. The DMC is governed by a charter that outlines the working 
procedures and responsibilities of the DMC. The Steering Committee will define the working 
procedures and responsibilities of the DMC. The charter will be agreed upon in advance by the DMC 
and will adhere to good research practices.  
 
 
11.2 
Event Adjudication Committee 
The independent Event Adjudication Committee (EAC) will evaluate all events related to the study 
outcomes based on pre-established criteria in a prospective and blinded manner. EAC members 
must not be directly involved in the research and must include at least two qualified members. The 
EAC will not be aware of the study’s treatment assignments when evaluating events. Outcome 
adjudication will occur continuously throughout the blinded treatment phase of the study. 
 

83 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
12 STATISTICAL CONSIDERATIONS 
 
12.1 
 Study Design  
This study is a randomized, adaptive-platform Phase III clinical trial. The study evaluates the 
efficacy and safety of novel and repurposed therapies (investigational products [IPs]) in participants 
with symptoms of chronic fatigue from long COVID-19 following resolution of acute COVID-19 
infection. This study evaluates various IPs for chronic fatigue syndrome from long COVID-19 under 
a common platform.  
 
 
12.1.1 Internal Pilot Phase 
Due to the rapidly evolving knowledge regarding LONG COVID, it is necessary to assess 
various aspects related to the study’s feasibility that need to be evaluated as soon as we begin 
implementation.  
 
The objective of the internal pilot phase is to identify and resolve any unforeseen feasibility 
issues to enhance the overall success of the research. In particular, we will assess issues related to 
recruitment, informed consent, medication availability and administration, and data collection and 
recording. There will be no analysis of clinical results at the end of this phase—since participants will 
be transferred to the main study and analyzed collectively. This will involve a blinded analysis of up 
to 10% of the target sample size, with an initial focus on the safety and tolerability of the 
investigational products under evaluation. 
 
 
12.1.2 The Main Clinical Study 
This phase involves the full implementation of the clinical trial, with the primary clinical 
endpoint being a reduction in perceived fatigue on the Fatigue Severity Scale (FSS). This phase is 
also an adaptive phase, with three interim analyses to evaluate the effects against the placebo arm. 
The main adaptations include:  
 
I. Discarding the placebo arm if there is strong evidence of benefit.  
II. Discard active study arms that show statistically unfavorable results.  
III. Partnering with study arms of common interest from other study platforms, with the goal 
of obtaining responses in less time compared to conducting the study in isolation.  

84 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
IV. Add new arms with investigational medicinal products that demonstrate significant 
potential for benefit in preclinical and Phase II clinical evidence (safety, tolerability, and 
potential dose-effectiveness). 
 
There will be three interim analyses (at 25%, 50%, and 75% of the proposed sample size of 
1,500 participants, with 500 participants per intervention arm) to assess the effects of the proposed 
interventions compared with the placebo arm. 
 
 
12.2 
 Randomization  
Participants will be randomly assigned to one of the study arms in an equal allocation (e.g., 
1:1:1). Stratified permuted block randomization will be used for this study. Randomization will be 
stratified by participating primary care facility with varying block sizes of participants. We will use a 
computer-generated interactive voice/web response system to implement randomization. For each 
active drug arm, there will be a placebo (or active control) arm, including for the different formulations 
and dosages in the study.  
 
12.3 
Sample Size Calculation l 
The sample size of 500 participants per arm and its operational characteristics were 
confirmed using closed-form, analytical, and numerical methods. The operational characteristics for 
the head-to-head comparison of the treatment arm versus the placebo arm in reducing the mean 
fatigue score measured by the Fatigue Severity Scale (1 to 9) on day 60 are shown inTable2 . For 
each pairwise comparison against the placebo arm, the Type I error rate (alpha) was set at 0.025 
(one-sided) using a Bayesian normal-normal model. For the planning of our study, we assumed a 
plausible standard deviation value of 1.7, which was estimated from a recent study that evaluated 
the psychometric properties of the fatigue severity scale in participants recovering from COVID-19.1 
 
Table2 : Simulated operational characteristics of our study for varying sample sizes 
Dropout rate 
Reduction in FSS score 
Sample  
(n = 252) 
Sample  
(n = 500) 
Sample  
(n = 752) 
Sample  
(n = 1000) 
0.0 
0.00 
2.5% 
2.5% 
2.5% 
2.5% 
0.15 
13.2% 
22.6% 
32.3% 
41.5% 
0.30 
41.8% 
71.2% 
87.8% 
95.2% 

85 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
Dropout rate 
Reduction in FSS score 
Sample  
(n = 252) 
Sample  
(n = 500) 
Sample  
(n = 752) 
Sample  
(n = 1000) 
0.45 
76.8% 
97.1% 
99.7% 
100.0% 
2.5 
0.00 
2.5% 
2.5% 
2.5% 
2.5% 
0.15 
12.9% 
22.0% 
31.5% 
40.5% 
0.30 
40.6% 
69.7% 
86.8% 
94.7% 
0.45 
75.4% 
96.6% 
99.7% 
100.0% 
5.0 
0.00 
2.5% 
2.5% 
2.5% 
2.5% 
0.15 
12.6% 
21.6% 
30.8% 
39.6% 
0.30 
39.5% 
68.5% 
85.9% 
94.1% 
0.45 
73.9% 
96.3% 
99.6% 
100.0% 
10.0 
0.00 
2.5% 
2.5% 
2.5% 
2.5% 
0.15 
12.2% 
20.6% 
29.4% 
37.8% 
0.30 
37.7% 
66.1% 
84.0% 
92.9% 
0.45 
71.5% 
95.4% 
99.4% 
99.9% 
 
 
Thus, the clinical trial will recruit 1,500 participants, divided into three groups of 500 
participants each. With the proposed sample size of 500 participants in each group, the study will 
have adequate statistical power to detect a clinically significant treatment effect. A difference of 0.45 
has been suggested as the minimum clinically important difference (MID) on the fatigue severity 
scale in population groups of participants with multiple sclerosis and chronic fatigue.2 Even with a 
10% dropout rate, our estimated power to detect a difference of 0.45 is above 90%.  
 
During interim analyses, the unblinded statistician advising the DMC will make 
recommendations regarding sample size based on the ongoing evaluation of global data and 
epidemiological data from Brazil and the state of Minas Gerais. We are continuously monitoring the 
literature for new findings relevant to chronic fatigue and to participants with long-haul COVID-19.  
 
12.4 
Statistical analysis and reporting 
 
The analysis and reporting of results follow the CONSORT guidelines (www.consort-
statement.org). The participant selection process and flow throughout the study will be summarized 

86 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
using a flow diagram. The results of the analysis of participants’ demographic data and baseline 
outcome variables (primary and secondary) will be summarized using descriptive summary 
measures: expressed as mean (standard deviation) or median (minimum-maximum) for continuous 
variables, as appropriate, and number (percentage) for categorical variables. We will adopt an 
intention-to-treat principle to analyze all outcomes.  
 
Bayesian statistics is the standard statistical framework. Statistical analyses of IPs are limited 
to simultaneously randomized controlled data. Sequential designs with Bayesian stopping rules are 
expected to be used to evaluate multiple IPs. Recruitment for an IP will be stopped before the 
maximum sample size using pre-specified decision rules. The maximum sample size and 
corresponding decision rules are determined a priori by dedicated statisticians and methodologists, 
who will remain blinded during the conduct of the study. The statistical analysis plan (SAP) will be 
formulated to ensure that the expected one-sided Type I error is less than 0.025 for each treatment. 
We will also use multiple imputation to handle missing data. For all models, results will be expressed 
as the effect reported as the mean difference for continuous outcomes, odds ratios (OR) for binary 
outcomes, and hazard ratios (HR) for time-to-event outcomes, with their respective 95% confidence 
or credibility intervals.  
 
All analyses will be performed using the latest version of R at the time of analysis. A detailed 
analysis plan will be developed prior to database lock. Any relevant safety data specific to Brazil will 
be immediately reported to our group for appropriate regulatory action. 
 
 
12.5 
Analysis of primary and secondary outcomes  
 
To analyze the primary outcome of the mean fatigue score at day 90 as measured by the 
Fatigue Severity Scale, we will use the Bayesian normal-normal model with non-informative prior 
distributions for the group means. This analysis will be adjusted for prespecified covariates. For all 
other continuous outcomes, we will use similar modeling approaches. For all binary outcomes, we 
will use logistic regression for analysis. The Cox proportional hazards model will be used for all time-
to-event outcomes. All analyses of secondary outcomes will be exploratory in nature, without 
adjustment for alpha across multiple secondary analyses. 
 
 
12.6 
Sensitivity Analyses 

87 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
We will perform several sensitivity analyses to assess the robustness of the results, 
particularly for the primary outcome. These include:  
i) 
Protocol-based analysis limited to participants who adhered to the protocol as 
described;  
ii) 
Competitive risk analysis: This analysis will treat death as a competitive risk factor for 
any outcome;  
iii) 
Missing data analysis: This analysis will assess the impact of missing data on the 
primary outcomes.  
iv) 
We will also conduct sensitivity analyses to account for any unforeseen issues that 
arise during the study process and that may affect the main conclusions. 
 
 
12.7 
Subgroup analyses 
 
We will conduct several subgroup analyses to assess the consistency of effects across 
subgroups of participants: 
i. Age - Assumption that older participants will benefit more than younger ones. 
ii. Gender - Assumption that female participants will benefit more than male 
participants. 
iii. Vaccination status - Assumption that vaccinated participants will benefit more 
than unvaccinated participants. 
iv. Comorbidities at screening: 
• 
Obesity status (yes or no)  
• 
Cardiovascular disease (yes or no); 
• 
Lung disease (yes or no); 
 
Our hypothesis is that participants with the clinical comorbidities described above will benefit 
more than those without these clinical conditions. All subgroup hypotheses are based on emerging 
data from other countries indicating the differential impact of COVID-19 by age, sex, vaccination 
status, and the presence of clinical comorbidities at baseline. Subgroup effects will be assessed by 
including an interaction term between the treatment group and the subgroup variables. These 
interaction effects will be exploratory in nature.  
 
12.8 
Missing Data 
Due to the study design and short duration, we expect to obtain data from all participants. 
However, in the unlikely event of missing data, they will be addressed.  

88 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
12.9 
Policy on pooled analysis 
It is expected that data from individual participants in similar studies may be pooled in a 
pooled analysis. De-identified data from the present study may be made available for these purposes 
following discussion by the Steering Committee and in accordance with a policy of academic-
scientific cooperation to find solutions for the treatment of long COVID-19.  
 

89 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
12.11 Summary table of analyses from the website  
Result 
Hypothesis 
Outcome 
Measure 
Statistical analysis 
method 
Primary 
Mean score measured by the 
fatigue severity scale on day 60 
after randomization 
 
Drug treatment will be 
better than placebo 
 
Fatigue Severity 
Scale 
 
Bayesian 
Normal-
Normal analysis  
Secondary 
Mean score measured by the 
fatigue severity scale on day 30 
after randomization  
 
 
Drug treatment will be 
better than placebo 
 
Fatigue Severity 
Scale 
 
Bayesian 
Normal-
Normal Analysis  
Mean score measured by the 
fatigue severity scale on day 90 
after randomization  
 
Drug treatment will be 
better than placebo 
Fatigue Severity 
Scale 
Bayesian 
Normal-
Normal Analysis  
Health-related quality of life on 
day 60 after randomization 
Drug treatment will be 
better than placebo 
 
Bayesian 
Normal-
Normal Analysis  
All-cause mortality by day 60 
after randomization 
Treatment will prevent 
overall mortality 
Measuring deaths 
in the groups 
Logistic regression 
Time to all-cause mortality up to 
day 60 after randomization 
The 
treatment 
will 
prevent 
overall 
mortality 
Interval in days 
between 
randomization 
and mortality 
Cox regression 
Unexpected hospitalization from 
any cause by day 60 after 
randomization 
The 
treatment 
will 
prevent hospitalization 
Measurement of 
deaths 
in 
the 
groups 
Logistic regression 
Unexpected hospitalization for 
any cause up to day 60 after 
randomization 
The 
treatment 
will 
prevent hospitalization 
Interval in days 
between 
randomization 
and mortality 
Cox regression 
Safety of the IP 
The drugs are safe in 
participants with long 
COVID 
Measurement of 
adverse events in 
treatment groups 
Descriptive analysis 
3) Subgroup analysis: 
    i) Age (young vs. elderly) 
 
 
 
  (ii) Sex (male vs. female)  
         female) 
 
 
Older adults are at 
higher 
risk 
of 
complications 
 
Men are at higher risk 
 
 
 
Risk assessment 
Regression methods 
with 
appropriate 
interaction terms.  

90 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
iv) Vaccination status 
 
 
 
v) Obesity  
 
 
vi) Diabetes 
 
vii) Hypertension 
 
viii) 
Cardiovascular disease  
 
 
ix) Chronic lung disease 
 
Unvaccinated 
individuals 
are 
at 
higher risk 
 
 
Obesity 
carries 
a 
higher risk 
 
Diabetes 
carries 
a 
higher risk 
 
People with high blood 
pressure are at higher 
risk 
 
 
Lung disease carries a 
higher risk 
 
 
4) Sensitivity analysis  
 
 
The 
results 
remain 
robust 
Primary and key 
secondary 
outcomes (fatigue 
score at day 30 
and day 60) 
 
 
IMPORTANT NOTES: 
• 
In all analyses, results will be expressed as estimated effects with corresponding 95% uncertainty 
estimates 
 
 
 

91 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
13 ETHICAL CONSIDERATIONS OF THE STUDY 
 
13.1 
Ethical conduct of the study 
 
The study will be conducted in accordance with the principles of the World Medical 
Association’s Declaration of Helsinki 229 and the International Council for Harmonisation (ICH) 
guidelines for Good Clinical Practice (GCP), as amended. 
 
The investigator must ensure the anonymity of all study participants. Each participant must 
be assigned a unique participant number, which must be used on all forms associated with the 
participant’s documents or samples that will be provided to the sponsor or any party performing tests 
on behalf of the sponsor (e.g., blood for central laboratory testing). 
 
All anonymous data remain the property of the Steering Committee. 
 
 
13.2 
Informed consent 
 
The participants’ individual medical information obtained as a result of this study is 
considered confidential, and its disclosure to unauthorized persons is prohibited. Participant 
confidentiality will be ensured by using unique participant numbers instead of names. If the results 
of this study are reported in medical journals or at meetings, or if they are submitted to the 
appropriate regulatory authorities in connection with regulatory procedures, such as applications for 
marketing authorization of pharmaceutical products, the participant’s identity will not be disclosed. 
 
With the participant’s permission, medical information may be provided to the participant’s 
personal physician or other appropriate medical staff responsible for the participant’s well-being. 
 
In accordance with GCP guidelines, all participants will be informed about the purpose of the 
research, the possible risks, and their right to withdraw from the study at any time, without any harm 
and without risk to their future medical care at the center. Each participant must agree to cooperate 
in all aspects of the study and must provide written confirmation (signed informed consent form) to 
the investigator prior to participation in the study. If the informed consent form is modified during the 
course of the study, active participants must sign the new version to continue participating in the 
study. For any updated or revised ICF, if applicable, the participant record must state that written 
informed consent was obtained for the use of the updated/revised consent form for continued 
participation in the clinical study. The ICF must be revised whenever there are changes to the 

92 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
procedures in the protocol amendment associated with the ICF procedures or when new information 
becomes available that may affect the participant’s willingness to participate. Each participant will 
receive a copy of each version of the form that they sign before and during the study. 
Informed consent may be obtained in electronic format, with a copy made available to the 
participant. In this situation, the Ethics Committee must approve the step-by-step procedure to be 
adopted in the process of obtaining informed consent, which must be approved in advance so that 
this method may be adopted by participating centers.  
 
No participant should participate in study activities until informed consent has been obtained. 
Documentation of the informed consent process and the discussion of the information provided to 
the participant must be included in the participant’s medical record and include a statement that 
informed consent was obtained prior to participation in the study. Signed forms (ICFs) must remain 
in the participant’s files and must be available for review by monitors, auditors, and/or inspectors 
from regulatory agencies at any time.  
 
 
13.3 
Research Ethics Committee (CEP)  
 
All researchers participating in this study must be governed by an appropriate REC. The 
REC/CONEP system must review and approve this protocol, the TCLE, the study documents, and 
any information to be provided to the participant before a site may begin conducting any study-
related activities.  
 
Subsequently, the investigator is responsible for obtaining renewed approval from the CEP 
annually, or more frequently, in accordance with regulatory requirements and the policies and 
procedures established by the CEP. Copies of the investigator’s annual report and other reports 
required to be submitted to the CEP, as well as copies of the CEP’s ongoing approval, must be 
provided to the Steering Committee. The investigator must also inform the REC of any protocol 
changes or amendments, expedited SAE reports submitted to regulatory authorities, and other 
significant safety concerns, in accordance with the IRB policy. Written documentation of the IRB’s 
approval of protocol amendments must be received prior to their implementation. Upon completion 
or termination of the study, investigators must notify their IRBs. The investigator shall comply with 
IRB policies throughout the study period. 

93 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
14 QUALITY CONTROL AND QUALITY ASSURANCE 
 
 
The integrity and quality of participant data will be ensured through training and instruction 
on the completion of clinical records, quality control checks, ongoing analysis of clinical data 
(including medical history and safety reviews), and verification and reconciliation of source data. 
 
The investigator will also allow the Steering Committee or its audit representative, the CEP, 
ANVISA, or other regulatory authority inspectors to review and inspect the facilities, procedures, and 
all records relevant to this study. These records include, among others, the informed consent form 
signed by the participant, source documentation, regulatory and essential documents, clinical 
records, and drug accounting records.  
 
The following measures will be taken to ensure that the study is conducted by the research 
center in accordance with the study protocol, GCP, and other applicable regulatory requirements: 
• 
Meeting with the investigator 
• 
Site Initiation Visit 
• 
Routine monitoring of the study and the research center, if applicable 
• 
Training on the protocol and documented GCP 
• 
Review of medical records and questionnaires against source documents 
• 
Collection of normal reference ranges from the local laboratory 
 
 
14.1 
Quality management: critical processes and data 
 
The following processes and data were identified during the risk management activities for 
this study as essential to ensuring the protection of human participants and the reliability of the study 
results. 
 
Throughout the study, the clinical study team will work to ensure that the clinical study is 
operationally feasible, focusing on the study and on activities essential to the protection of human 
participants and the reliability of the study results, including, but not limited to, the following: 
 
Design and implementation of the study protocol. 
Tools and procedures for collecting and processing supporting data. 
Tools and procedures to ensure the rights and protection of research participants. 
Activities essential for study decision-making and adherence. 

94 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
15 REPORTING AND DATA RECORDING 
 
 
Source documents are original documents, data, and records (e.g., case histories, physician 
progress notes, nursing notes, medical records, hospital records, clinical and office charts, laboratory 
notes, evaluation memos or checklists, pharmacy dispensing records, automated instrument data 
records, certified copies or transcripts after verification as accurate and complete, records 
maintained in the pharmacy or laboratories, and participant records). Source data are contained in 
the source documents and must be sufficient to reconstruct all data transcribed into clinical records 
and to evaluate the study. Examples of source data include clinical findings, observations, 
summaries of inclusion information and RCT procedures, assessment of the clinical significance of 
laboratory results, severity and intensity of AEs, and the investigator’s judgment regarding the 
relationship of AEs to study medications. 
 
The investigator must prepare and maintain adequate and accurate case records that 
document all observations and other data relevant to the investigation for all participants. 
 
Source documentation must be available during the monitoring visit to verify the data entered 
in the eCRFs, as necessary. Source documentation must also be available for verification by auditors 
and/or inspectors, as necessary. 
 
 
15.1 
 Documentation source 
 
The investigator must maintain adequate and accurate source documents on which the case 
reports for each participant are based. They must be separate and distinguishable. These records 
must include detailed notes on: 
• 
The medical history prior to study participation; 
• 
Basic identifying information, such as demographic data, that links the participant’s 
source documents; 
• 
The results of all diagnostic tests performed, diagnoses made, therapy provided, and 
any other data regarding the participant’s medical condition; 
• 
The participant’s exposure to the study treatment; 
• 
All AEs and pregnancies; 
• 
All special circumstances; 
• 
The participant’s exposure to any concomitant therapy; 

95 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
• 
All relevant observations and data regarding the participant’s clinical condition during 
the study; 
• 
Verbal and written communication with the participant regarding the study treatment 
(including the risks and benefits of the study); the date of informed consent must be 
recorded in the source documentation. 
 
All study data must be available in the source documentation. 
 
 
15.2 
Medical records 
 
A clinical record is designed to record all information required by the protocol to be reported 
on each clinical trial participant. The investigator is responsible for ensuring the accuracy, 
completeness, legibility, clarity, and timeliness of the data reported in participants’ clinical records. 
Reported data transcribed from source documents must be consistent with the source documents, 
or discrepancies must be explained. An explanation must be provided for all missing data. 
 
All clinical record data and visit reports must be entered only by the clinical study staff 
designated by the investigator. The site staff will receive appropriate training before accessing the 
electronic data capture (EDC) system. 
 
Any change or correction to a medical record will be tracked via an audit trail within the EDC 
system. The audit trail will contain the original data value, the new data value, the date it was 
changed, the user who made the change, and the reason(s) for the change. 
 
Health records must be completed in a timely manner for the respective visit (for example, 
the site should not wait for a monitoring visit before entering the data). Data from clinical records and 
visits will be tracked and entered into a clinical database. The database system will be a secure, 
password-protected system with a full audit trail utility. 
Participant data will be reviewed through scheduled quality checks and manually by 
reviewing data lists. Data that appear inconsistent, incomplete, or inaccurate will be flagged by the 
site for clarification. Data corrections will be updated in the database and tracked in the audit trail. 
AEs and concomitant medications will be coded using standardized healthcare dictionaries (e.g., 
MedDRA and the World Health Organization Drug Dictionary). 
The investigator is responsible for reviewing, verifying, and approving all participant data (e.g., 
medical records and completed questionnaires). 

96 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
15.3 
Record Retention 
 
The investigator must maintain adequate records for the study, including complete clinical 
records, medical records, laboratory reports, signed ICFs, drug distribution records, adverse event 
reports, information on participants who discontinued the study, all correspondence with the IRB and 
the research steering committee, and other relevant data. 
The investigator must maintain all records at the healthcare institution. The investigator must 
notify in writing the transfer of any study records outside the research institution after the study’s 
completion. The retention period for research records is that recommended by regulatory authorities 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
16 PROCEDURES FOR PROTOCOL AMENDMENTS OR EARLY TERMINATION OF THE 
STUDY 
 
 
16.1 
Protocol Deviation 
 
The investigator must not perform unplanned procedures or deviate from the protocol without 
prior written approval, except in medical emergencies. In the event of a medical emergency, the 
investigator must notify the medical monitor as soon as possible. Any other changes to the protocol 
must be implemented as an amendment to the protocol. The criteria for describing protocol 
deviations and how they will be handled will be documented in the study manual. 

97 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
16.2 
Protocol Amendments 
 
Changes to the protocol, except when necessary to eliminate an immediate risk to 
participants, shall be made only with the prior approval of the Steering Committee. Each applicable 
regulatory authority/IRB must review and approve the changes prior to their implementation. 
Approval from the regulatory authority/IRB does not need to be obtained prior to the removal of an 
immediate risk to participants. 
 
16.3 
Study termination 
 
The Steering Committee reserves the right to terminate the study in its entirety or at a single 
site at any time. Reasons for termination may include (but are not limited to) unsatisfactory 
enrollment of participants in terms of quality and/or quantity, the site’s failure to meet the 
requirements of the protocol or GCP, or inaccurate and/or incomplete data recording. 
In the event of study termination, the Steering Committee and the investigator must ensure 
that due consideration is given to protecting the interests of the subjects. Both parties must organize 
the procedures individually following the review and site visit, and in accordance with the study 
contract. 
Based on its analysis of the data, the DMC may make recommendations to discontinue the 
study, as indicated in the DMC’s internal bylaws. The Steering Committee will determine whether 
the study should be discontinued early. 
The study may be terminated or suspended at the request of regulatory authorities. 

98 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
17 PUBLICATION AND DATA SHARING POLICY 
 
Data generated through this research protocol belong to the Steering Committee. No data 
may be disclosed or published without the prior consent of the Steering Committee. The 
confidentiality agreement to be established with the participating research centers will set forth the 
publication policy. 
 
In accordance with applicable laws and regulations, the sponsor will record and publicly 
provide all mandatory information related to this study, including, to the extent and within the 
timeframes required, a summary of the clinical trial data and results. 
 
 

99 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
REFERENCES 
 
 
 
1  
Naik H, Shao S, Tran KC, et al. Assessment of fatigue in participants recovering from COVID-
19: validation of the Fatigue Severity Scale and single-item screening questions. Health and 
Quality of Life Outcomes 2022; 20(1): 1-9. 
 
2  
Rooney S, McFadyen DA, Wood DL, Moffat DF, Paul PL. Minimally important difference of the 
Fatigue Severity Scale and the Modified Fatigue Impact Scale in people with multiple sclerosis. 
Mult Scler Relat Disord 2019; 35: 158-63. 
 
3  
WHO. Novel Coronavirus–China. 2020a. Available at:  https://www.who.int/csr/don/12- january-
2020-novel-coronavirus-china/en/. Accessed on: March 21, 2020. 
 
4  
ZHOU P, YANG XL, WANG XG, HU B, ZHANG L, ZHANG W, et al. Discovery of a novel 
coronavirus associated with the recent pneumonia outbreak in humans and its potential bat 
origin. bioRxiv. 2020; doi: https://doi.org/10.1101/2020.01.22.914952 
 
5  
WHO. Novel Coronavirus (2019-nCoV) Situation Report – 11. 2020b. Available at: 
https://www.who.int/docs/default-source/coronaviruse/situation-reports/20200131-sitrep-11-
ncov.pdf?sfvrsn=de7c0f7_4 .  Accessed on: March 21, 2020. 
 
6  
WHO. Novel Coronavirus (2019-nCoV) Situation Report – 22. 2020. Available at: 
https://www.who.int/docs/default-source/coronaviruse/situation-reports/20200211-sitrep-22-
ncov.pdf?sfvrsn=fb6d49b1_2 . Accessed on: March 21, 2020. 
 
7  
GORBALENYA, Alexander E.; BAKER, Susan C.; BARIC, Ralph S.; GROOT, Raoul J. de; 
DROSTEN, Christian; GULYAEVA, Anastasia A.; HAAGMANS, Bart L.; LAUBER, Chris; 
LEONTOVICH, Andrey M; NEUMAN, Benjamin W.; PENZAR, Dmitry; PERLMAN, Stanley; 
POON, Leo L.M.; SAMBORSKIY, Dmitry; SIDOROV, Igor A.; SOLA, Isabel; ZIEBUHR, John. 
Severe acute respiratory syndrome-related coronavirus: The species and its viruses – a 
statement of the Coronavirus Study Group. Available at: bioRxiv 2020.02.07.937862; doi: 
https://doi.org/10.1101/2020.02.07.937862 . 
 
 

100 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
8  
WHO Director-General's opening remarks at the media briefing on COVID-19 - March 11, 2020 
[Internet]. World Health Organization. World Health Organization; 2020 [cited 2020Mar19]. 
Available at: https://www.who.int/dg/speeches/detail/who-director-general-s-opening-remarks -
at-the-media-briefing-on-covid-19---11-march-2020 Accessed on March 21, 2020.  
 
9  
WHO Coronavirus disease 2019 (COVID-19) Situation report – 62. Retrieved on March 23, 
2020, 
and 
available 
at 
https://www.who.int/docs/default-source/coronaviruse/situation-
reports/20200322-sitrep-62-covid-19.pdf?sfvrsn=f7764c46_2 
 
10  Zhou P, Yang XL, Wang XG, Hu B, Zhang L, Zhang W, Si HR, Zhu Y, Li B, Huang CL, Chen 
HD, Chen J, Luo Y, Guo H, Jiang RD, Liu MQ, Chen Y, Shen XR, Wang X, Zheng XS, Zhao K, 
Chen QJ, Deng F, Liu LL, Yan B, Zhan FX, Wang YY, Xiao GF, Shi ZL (2020) A pneumonia 
outbreak 
associated 
with 
a 
new 
coronavirus 
of 
probable 
bat 
origin. 
Nature. 
https://doi.org/10.1038/s41586-020-2012-7 
 
11  Xu X, Chen P, Wang J, Feng J, Zhou H, Li X, Zhong W, Hao P (2020) Evolution of the novel 
coronavirus from the ongoing Wuhan outbreak and modeling of its Spike protein for risk of 
human transmission. Sci China Life Sci. https://doi.org/10.1007/s11427-020-1637-5 
 
12  Zhang H, Penninger JM, Li Y, Zhong N, Slutsky AS. Angiotensin-converting enzyme 2 (ACE2) 
as a SARS-CoV-2 receptor: molecular mechanisms and potential therapeutic target. Intensive 
Care Medicine. 2020 Mar 3:1-5. https://doi.org/10.1007/s00134-020-05985-9. 
 
13  Kuba K, Imai Y, Rao S, Gao H, Guo F, Guan B, Huan Y, Yang P, Zhang Y, Deng W, Bao L. A 
crucial role of angiotensin-converting enzyme 2 (ACE2) in SARS coronavirus–induced lung 
injury. Nature Medicine. 2005 Aug;11(8):875-9. 
 
14  Ebrahimi N, Aslani S, Babaie F, Hemmatzadeh M, Hosseinzadeh R, Joneidi Z, et al. Recent 
Findings on the Coronavirus Disease 2019 (COVID-19); Immunopathogenesis and 
Immunotherapeutics. 
Int 
Immunopharmacol 
(2020) 
89:107082. 
doi: 
10.1016/j.intimp.2020.10708  
15  Katze MG, He Y, Gale MJr. Viruses and Interferon: A Fight for Supremacy. Nat Rev Immunol 
(2002) 2:675–87. doi: 10.1038/nri888 
 

101 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
 
16  Bernet J, Mullick J, Singh AK, Sahu A. Viral Mimicry of the Complement System. J Biosci (2003) 
28:249–64. doi: 10.1007/bf02970145  
 
17  Schulz KS, Mossman KL. Viral Evasion Strategies in Type I IFN Signaling - A Summary of 
Recent Developments. Front Immunol (2016) 7:498. doi: 10.3389/fimmu.2016.00498 
 
18  Chu H, Chan JF, Wang Y, Yuen TT, Chai Y, Shuai H, et al. SARS-CoV-2 Induces a More Robust 
Innate Immune Response and Replicates Less Efficiently Than SARS-CoV in the Human 
Intestines: An Ex Vivo Study With Implications on Pathogenesis of COVID-19. Cell Mol 
Gastroenterol Hepatol (2020) 11(3):771–81. doi: 10.1016/j.jcmgh.2020.09.017. 
 
19  Pedersen SF, Ho Y-C. SARS-CoV-2: A Storm is Raging. J Clin Invest (2020) 130:2202–5. doi: 
10.1172/JCI137647. 
 
20  Schurink B, Roos E, Radonic T, Barbe E, Bouman CSC, de Boer HH, et al. Viral Presence and 
Immunopathology in Patients With Lethal COVID-19: A Prospective Autopsy Cohort Study. 
Lancet Microbe (2020) 1:e290–9. doi: 10.1016/S2666-5247(20)30144-0  
 
21  Rosen HR, O'Connell C, Nadim MK, DeClerck B, Sheibani S, DePasquale E, et al. 
Extrapulmonary Manifestations of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-
CoV-2) Infection. J Med Virol (2020) 93(5):2645–53. doi: 10.1002/jmv.26595  
 
22  Qi F, Qian S, Zhang S, Zhang Z. Single-Cell RNA Sequencing of 13 Human Tissues Identifies 
Cell Types and Receptors of Human Coronaviruses. Biochem Biophys Res Commun (2020) 
526:135–40. doi: 10.1016/j.bbrc.2020.03.044  
 
23  Merad M, Martin JC. Pathological Inflammation in Patients With COVID-19: A Key Role for 
Monocytes and Macrophages. Nat Rev Immunol (2020) 20:355–62. doi: 10.1038/s41577-020-
0331-4 
24  Zheng M, Schultz MB, Sinclair DA. NAD+ in COVID-19 and viral infections. Trends Immunol. 
2022 Feb 11:S1471-4906(22)00025-4. doi: 10.1016/j.it.2022.02.001 
 
 

102 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
25  Siu, K.-L. et al. (2019) Severe acute respiratory syndrome coronavirus ORF3a protein activates 
the NLRP3 inflammasome by promoting TRAF3-dependent ubiquitination of ASC. FASEB J. 33, 
8865–8877  
 
26  Rodrigues, T.S. et al. (2021) Inflammasomes are activated in response to SARS-CoV-2 infection 
and are associated with COVID-19 severity in patients. J. Exp. Med. 218, e20201707  
 
27  Verdin, E. (2015) NAD+ in aging, metabolism, and neurodegeneration. Science 350, 1208–1213  
 
28  Gross, O.; Thomas, C.J.; Guarda, G.; Tschopp, J. The inflammasome: an integrated view. 
Immunol. Rev. 2011, 243, 136–151. 
 
29  Suárez, R.; Buelvas, N. Inflammasome: activation mechanisms. Investig. Clin. 2015, 56, 74–99.  
 
30  Kolbrink, B.; Riebeling, T.; Kunzendorf, U.; Krautwald, S. Plasma Membrane Pores Drive 
Inflammatory Cell Death. Front. Cell Dev. Biol. 2020, 8.  
 
31  El-Sharkawy, L.Y.; Brough, D.; Freeman, S. Inhibiting the NLRP3 inflammasome. Molecules 
2020, 25, 5533.   
 
32  Weber, A.N.R.; Bittner, Z.A.; Shankar, S.; Liu, X.; Chang, T.-H.; Jin, T.; Tapia-Abellán, A. Recent 
insights into the regulatory networks of NLRP3 inflammasome activation. J. Cell Sci. 2020, 133, 
jcs248344. 
 
33  Moretti, J.; Blander, J.M. Increasing complexity of NLRP3 inflammasome regulation. J. Leukoc. 
Biol. 2020.  
 
34  Zhou, R.; Tardivel, A.; Thorens, B.; Choi, I.; Tschopp, J. Thioredoxin-interacting protein links 
oxidative stress to inflammasome activation. Nat. Immunol. 2010, 11, 136–140. 
 
 

103 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
35  Oslowski, C.M.; Hara, T.; O’Sullivan-Murphy, B.; Kanekura, K.; Lu, S.; Hara, M.; Ishigaki, S.; 
Zhu, L.J.; Hayashi, E.; Hui, S.T.; et al. Thioredoxin-interacting protein mediates ER stress-
induced Î2 cell death through initiation of the inflammasome. Cell Metab. 2012, 16, 265–273. 
 
36  Kobayashi, A.; Ohta, T.; Yamamoto, M. Unique Function of the Nrf2–Keap1 Pathway in the 
Inducible Expression of Antioxidant and Detoxifying Enzymes. Methods Enzymol. 2004, 378, 
273–286.  
 
37  Naidu, S.D.; Dinkova-Kostova, A.T. KEAP1, a cysteine-based sensor and a drug target for the 
prevention and treatment of chronic disease. Open Biol. 2020, 10, 200105. 
 
38  Tanito, M.; Agbaga, M.-P.; Anderson, R.E. Upregulation of the thioredoxin system via the Nrf2-
antioxidant responsive element pathway in adaptive retinal neuroprotection in vivo and in vitro. 
Free Radic. Biol. Med. 2007, 42, 1838–1850.  
 
39  Thimmulappa, R.K.; Mai, K.H.; Srisuma, S.; Kensler, T.W.; Yamamoto, M.; Biswal, S. 
Identification of Nrf2-regulated genes induced by the chemopreventive agent sulforaphane using 
oligonucleotide microarray. Cancer Res. 2002, 62, 5196–5203.  
 
40  Brigelius-Flohé, R.; Muller, M.; Lippmann, D.; Kipp, A.P. The Yin and Yang of Nrf2-Regulated 
Selenoproteins in Carcinogenesis. Int. J. Cell Biol. 2012, 2012, 1–8. 
 
41  Fayez, A.M.; El-Emam, S.Z.; Moustafa, D. Alpha lipoic acid exerts an antioxidant effect via 
Nrf2/HO-1 pathway activation and suppresses methotrexate-induced activation of hepatic 
stellate cells in rats. Biomed. Pharmacother. 2018, 105, 428–433.  
 
42  Mahmoud, A.M.; Hussein, O.E.; Hozayen, W.G.; Bin-Jumah, M.; El-Twab, S.M.A. Ferulic acid 
prevents oxidative stress, inflammation, and liver injury via upregulation of Nrf2/HO-1 signaling 
in methotrexate-induced rats. Environ. Sci. Pollut. Res. 2020, 27, 7910–7921. 
43  Ruhee, R.T.; Suzuki, K. The Integrative Role of Sulforaphane in Preventing Inflammation, 
Oxidative Stress, and Fatigue: A Review of a Potential Protective Phytochemical. Antioxidants 
2020, 9, 521.  
 

104 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
44Alzokaky, A.A.; Abdelkader, E.M.; El-Dessouki, A.M.; Khaleel, S.A.; Raslan, N.A. C-phycocyanin 
protects against ethanol-induced gastric ulcers in rats: Role of the HMGB1/NLRP3/NF-κB 
pathway. Basic Clin. Pharmacol. Toxicol. 2020, 127, 265–277.  
 
45  Siddiqi, H. K. & Mehra, M. R. COVID-19 Illness in Healthy and Immunocompromised Individuals: 
A Clinical-Therapeutic Staging Proposal. The Journal of Heart and Lung Transplantation 
S105324982031473X (2020) doi:10.1016/j.healun.2020.03.012. 
 
46  Li, G. et al. Coronavirus infections and immune responses. J Med Virol 92, 424–432 (2020). 
 
47  Konig, M. F. et al. Preventing cytokine storm syndrome in COVID-19 using α-1 adrenergic 
receptor antagonists. J. Clin. Invest. (2020) doi:10.1172/JCI139642. 
 
48  Siddiqi, H. K. & Mehra, M. R. COVID-19 Illness in Native and Immunosuppressed States: A 
Clinical-Therapeutic Staging Proposal. The Journal of Heart and Lung Transplantation 
S105324982031473X (2020) doi:10.1016/j.healun.2020.03.012. 
 
49  Mehta, P. et al. COVID-19: consider cytokine storm syndromes and immunosuppression. The 
Lancet S0140673620306280 (2020) doi:10.1016/S0140-6736(20)30628-0. 
 
50  McGonagle, D., Sharif, K., O’Regan, A., & Bridgewood, C. The Role of Cytokines, including 
Interleukin-6, in COVID-19-induced Pneumonia and Macrophage Activation Syndrome-Like 
Disease. Autoimmunity Reviews 102537 (2020) doi:10.1016/j.autrev.2020.102537. 
 
51  Arentz, M. et al. Characteristics and Outcomes of 21 Critically Ill Patients With COVID-19 in 
Washington State. JAMA (2020) doi:10.1001/jama.2020.4326. 
 
52  Vital Surveillance: The Epidemiological Characteristics of an Outbreak of 2019 Novel 
Coronavirus 
Disease 
(COVID-19) 
— 
China, 
2020. 
http://weekly.chinacdc.cn/en/article/id/e53946e2-c6c4-41e9-9a9b-fea8db1a8f51 (2020). 
 
53  Xu, X. et al. Effective treatment of severe COVID-19 patients with tocilizumab. PNAS 
 
(2020) doi:10.1073/pnas.2005615117. 
 

105 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
 
54  Cavalli, G. et al. Interleukin-1 blockade with high-dose anakinra in patients with COVID-19, acute 
respiratory distress syndrome, and hyperinflammation: a retrospective cohort study. The Lancet 
Rheumatology S2665991320301272 (2020) doi:10.1016/S2665-9913(20)30127-2. 
 
55   Zhou, F. et al. Clinical course and risk factors for mortality of adult inpatients with COVID-19 in 
Wuhan, China: a retrospective cohort study. The Lancet S0140673620305663 (2020) 
doi:10.1016/S0140-6736(20)30566-3. 
 
56   Guan, W.-J. et al. Clinical Characteristics of Coronavirus Disease 2019 in China. N. Engl. J. 
Med. (2020) doi:10.1056/NEJMoa2002032. 
 
57   Chen, T. et al. Clinical characteristics of 113 deceased patients with coronavirus disease 2019: 
retrospective study. BMJ 368, m1091 (2020). 
 
58   Qin, C. et al. Dysregulation of immune response in patients with COVID-19 in Wuhan, China. 
Clinical Infectious Diseases ciaa248 (2020) doi:10.1093/cid/ciaa248. 
 
59  Wan, S. et al. Characteristics of lymphocyte subsets and cytokines in peripheral blood of 123 
hospitalized 
patients 
with 
2019 
novel 
coronavirus 
pneumonia 
(NCP). 
medRxiv 
2020.02.10.20021832 (2020) doi:10.1101/2020.02.10.20021832. 
 
60  Wu, C. et al. Risk Factors Associated With Acute Respiratory Distress Syndrome and Death in 
Patients With Coronavirus Disease 2019 Pneumonia in Wuhan, China. JAMA Internal Medicine 
(2020) doi:10.1001/jamainternmed.2020.0994 
 
61  Liu, J. et al. Longitudinal characteristics of lymphocyte responses and cytokine profiles in the 
peripheral 
blood 
of 
SARS-CoV-2-infected 
patients. 
http://medrxiv.org/lookup/doi/10.1101/2020.02.16.20023671 
(2020) 
doi:10.1101/2020.02.16.20023671. 
 
62  Chen, G. et al. Clinical and immunologic features in severe and moderate Coronavirus Disease 
2019. J. Clin. Invest. (2020) doi:10.1172/JCI137244. 
 

106 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
 
63  Chen, X. et al. Detectable serum SARS-CoV-2 viral load (RNAaemia) is closely associated with 
drastically elevated interleukin 6 (IL-6) levels in critically ill COVID-19 patients. medRxiv 
2020.02.29.20029520 (2020) doi:10.1101/2020.02.29.20029520. 
 
64  Liu, T. et al. The potential role of IL-6 in monitoring severe cases of coronavirus disease 2019. 
http://medrxiv.org/lookup/doi/10.1101/2020.03.01.20029769 
(2020) 
doi:10.1101/2020.03.01.20029769. 
 
65  Mehta, P. et al. COVID-19: consider cytokine storm syndromes and immunosuppression. The 
Lancet S0140673620306280 (2020) doi:10.1016/S0140-6736(20)30628-0. 
 
66  Channappanavar, R. & Perlman, S. Pathogenic human coronavirus infections: causes and 
consequences of cytokine storm and immunopathology. Semin Immunopathol 39, 529–539 
(2017). 
 
67  Wong, C. K. et al. Plasma inflammatory cytokines and chemokines in severe acute respiratory 
syndrome. Clin. Exp. Immunol. 136, 95–103 (2004). 
 
68  Mahallawi, W. H., Khabour, O. F., Zhang, Q., Makhdoum, H. M., & Suliman, B. A. MERS-CoV 
infection in humans is associated with a pro-inflammatory Th1 and Th17 cytokine profile. 
Cytokine 104, 8–13 (2018). 
 
69  Cai, X. An Insight into the Comparison between COVID-19 (2019-nCoV Disease) and SARS in 
Pathology and Pathogenesis. https://osf.io/hw34x (2020) doi:10.31219/osf.io/hw34x. 
 
70  Kim, E. S. et al. Clinical Progression and Cytokine Profiles of Middle East Respiratory Syndrome 
Coronavirus Infection. J Korean Med Sci 31, 1717 (2016). 
 
71  Lew, T. W. K. Acute Respiratory Distress Syndrome in Critically Ill Patients With Severe Acute 
Respiratory Syndrome. JAMA 290, 374 (2003). 
 
 

107 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
72  McGonagle, D., Sharif, K., O’Regan, A., & Bridgewood, C. The Role of Cytokines, Including 
Interleukin-6, in COVID-19-Induced Pneumonia and Macrophage Activation Syndrome-Like 
Disease. Autoimmunity Reviews 102537 (2020) 
 
73  Ramos-Casals, M., Brito-Zerón, P., López-Guillermo, A., Khamashta, M. A., & Bosch, X. Adult 
hemophagocytic syndrome. Lancet 383, 1503–1516 (2014). 
 
74  Karakike, E. & Giamarellos-Bourboulis, E. J. Macrophage Activation-Like Syndrome: A Distinct 
Entity Leading to Early Death in Sepsis. Front Immunol 10, 55 (2019). 
 
75  Crayne, C. B., Albeituni, S., Nichols, K. E., & Cron, R. Q. The Immunology of Macrophage 
Activation Syndrome. Front. Immunol. 10, 119 (2019). 
 
76  Brudno, J. N. & Kochenderfer, J. N. Toxicities of chimeric antigen receptor T cells: recognition 
and management. Blood 127, 3321–3330 (2016). 
 
77  Hay, K. A. et al. Kinetics and biomarkers of severe cytokine release syndrome after CD19 
chimeric antigen receptor–modified T-cell therapy. Blood 130, 2295–2306 (2017). 
 
78  Neelapu, S. S. et al. Chimeric antigen receptor T-cell therapy — assessment and management 
of toxicities. Nat Rev Clin Oncol 15, 47–62 (2018). 
 
79  Moore, J. B. & June, C. H. Cytokine release syndrome in severe COVID-19. Science 
 
368, 473–474 (2020). 
 
80  Gritti, G. et al. Use of siltuximab in patients with COVID-19 pneumonia requiring ventilatory 
support. 
http://medrxiv.org/lookup/doi/10.1101/2020.04.01.20048561 
(2020) 
doi:10.1101/2020.04.01.20048561. 
 
81  Sanofi: Press Releases, Monday, April 27, 2020. https://www.sanofi.com/en/media- room/press-
releases/2020/2020-04-27-12-58-00 
https://www.sanofi.com/media-room/press- 
releases/2020/2020-04-27 12-58-00 2022288. 
 
 

108 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
82  Sharma S, Kumar R, Shalimar. Management of Gastrointestinal Bleeding in Coronavirus 
Disease: Exploring the Options. Am J Gastroenterol (2020) 116 (4):843–4. doi: 
10.14309/ajg.0000000000000979 
 
83  Rodriguez-Nakamura RM, Gonzalez-Calatayud M, Martinez Martinez AR. Acute Mesenteric 
Thrombosis in Two Patients With COVID-19. Two Case Reports and Literature Review. Int J 
Surg Case Rep (2020) 76:409–14. doi: 10.1016/j.ijscr.2020.10.040 
 
84  Bhayana R, Som A, Li MD, Carey DE, Anderson MA, Blake MA, et al. Abdominal Imaging 
Findings in COVID-19: Preliminary Observations. Radiology (2020) 297:E207–15. doi: 
10.1148/radiol.2020201908 
 
85  Connors JM, Levy JH. COVID-19 and its Implications for Thrombosis and Anticoagulation. Blood 
(2020) 135:2033–40. doi: 10.1182/blood.2020006000  
 
86  Levi M, Thachil J, Iba T, Levy JH. Coagulation Abnormalities and Thrombosis in Patients With 
COVID-19. Lancet Haematol (2020) 7:e438–40. doi: 10.1016/S2352-3026(20)30145-9 
 
87  Mehta P, McAuley DF, Brown M, Sanchez E, Tattersall RS, Manson JJ, et al. COVID-19: 
Consider Cytokine Storm Syndromes and Immunosuppression. Lancet (2020) 395:1033–4. doi: 
10.1016/S0140-6736(20)30628-0 
 
88 Bitirgen G, Korkmaz C, Zamani A, et al. Corneal confocal microscopy identifies corneal nerve 
fiber loss and increased dendritic cells in patients with long COVID. British Journal of 
Ophthalmology 2022; 106(12): 1635-41. 
 
89 Xie Y, Al-Aly Z. Risks and burdens of incident diabetes in long COVID: a cohort study. The Lancet 
Diabetes & Endocrinology 2022; 10(5): 311-21. 
 
90 Xie Y, Xu E, Bowe B, Al-Aly Z. Long-term cardiovascular outcomes of COVID-19. Nature Medicine 
2022; 28(3): 583-90. 
 
 

109 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
91  Al-Aly Z, Xie Y, Bowe B: High-dimensional characterization of post-acute sequelae of COVID-
19. Nature 2021, 594:259-264  
  
92  Davis HE, Assaf GS, McCorkell L, et al.: Characterizing long COVID in an international cohort: 
7 months of symptoms and their impact. EClinicalMedicine 2021, 38:101019. 
 
93  Sudre CH, Murray B, Varsavsky T, Graham MS, Penfold RS, Bowyer RC, Pujol JC, Klaser K, 
Antonelli M, Canas LS, et al.: Attributes and predictors of long COVID. Nat Med 2021, 27:626-
631.  
  
94  Xie Y, Bowe B, Al-Aly Z: Burdens of post-acute sequelae of COVID-19 by severity of acute 
infection, demographics, and health status. Nat Commun 2021, 12:6571. 
 
95 Al-Aly Z, Xie Y, Bowe B. High-dimensional characterization of post-acute sequelae of COVID-19. 
Nature 2021; 594(7862): 259-64. 
 
96 Fernández-de-Las-Peñas C. Long COVID: current definition. Infection 2022; 50(1): 285-6. 
 
97 World Health Organization. A clinical case definition of post-COVID-19 condition by a Delphi 
consensus, October 6, 2021: World Health Organization, 2021. 
 
98 Munblit D, Nicholson T, Akrami A, et al. A core outcome set for post-COVID-19 condition in adults 
for use in clinical practice and research: an international Delphi consensus study. The Lancet 
Respiratory Medicine 2022. 
 
99  Forman CA, Munter SE, Hoh R, Tai V, et al.: Markers of immune activation and inflammation in 
individuals with post-acute sequelae of severe acute respiratory syndrome coronavirus 2 
infection. J Infect Dis 2021, 224:1839-1848. 
 
100  
Sun B, Tang N, Peluso MJ, Iyer NS, Torres L, Donatelli JL, Munter SE, Nixon CC, 
Rutishauser RL, Rodriguez-Barraquer I, et al.: Characterization and biomarker analyses of post-
COVID-19 complications and neurological manifestations. Cells 2021, 10:386 
 
 

110 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
101  
Ryan FJ, Hope CM, Masavuli MG, Lynn MA, Mekonnen ZA, Yeow AEL, Garcia-Valtanen P, 
Al-Delfi Z, Gummow J, Ferguson C, et al.: Long-term perturbation of the peripheral immune 
system months after SARS-CoV-2 infection. BMC Med 2022, 20:26. 
 
102  
Phetsouphanh C, Darley DR, Wilson DB, Howe A, Munier CML, Patel SK, Juno JA, Burrell 
LM, Kent SJ, Dore GJ, et al.: Immunological dysfunction persists for 8 months following initial 
mild-to-moderate 
SARS-CoV-2 
infection. 
Nat 
Immunol 
2022, 
23:210-216, 
https://doi.org/10.1038/s41590-021-01113-x. 
 
103  
Chun HJ, Coutavas E, Pine AB, Lee AI, Yu VL, Shallow MK, Giovacchini CX, Mathews AM, 
Stephenson B, Que LG, et al.: Immunofibrotic drivers of impaired lung function in postacute 
sequelae of SARS-CoV-2 infection. JCI Insight 2021, 6:e148476. 
 
104  
Proal AD, VanElzakker MB: Long COVID or post-acute sequelae of COVID-19 (PASC): an 
overview of biological factors that may contribute to persistent symptoms. Front Microbiol 2021, 
12:698169. 
 
105  
Chioh FW, Fong S-W, Young BE, Wu K-X, Siau A, Krishnan S, Chan Y-H, Carissimo G, Teo 
LL, Gao F, et al.: Convalescent COVID-19 patients are susceptible to endothelial dysfunction 
due to persistent immune activation. eLife 2021, 10:e64909. 
 
106  
Chang SE, Feng A, Meng W, Apostolidis SA, Mack E, Artandi M, Barman L, Bennett K, 
Chakraborty S, Chang I, et al.: New-onset IgG autoantibodies in hospitalized patients with 
COVID-19. Nat Commun 2021, 12:5417.  
 
107  
Wang EY, Mao T, Klein J, Dai Y, Huck JD, Jaycox JR, Liu F, Zhou T, Israelow B, Wong P, et 
al.: Diverse functional autoantibodies in patients with COVID-19. Nature 2021, 595:283-288.  
 
108  
Bastard P, Rosen LB, Zhang Q, Michailidis E, Hoffmann H-H, Zhang Y, Dorgham K, Philippot 
Q, Rosain J, Béziat V, et al.: Autoantibodies against type I IFNs in patients with life-threatening 
COVID-19. Science 2020, 370:eabd4585. 
 
 

111 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
109 Larsen NW, Stiles LE, Shaik R, et al. Characterization of autonomic symptom burden in long 
COVID: a global survey of 2,314 adults. Frontiers in Neurology 2022; 13: 1012668. 
 
110  Mancini DM, Brunjes DL, Lala A, Trivieri MG, Contreras JP, Natelson BH. Use of 
cardiopulmonary stress testing for patients with unexplained dyspnea following coronavirus 
disease. Heart Failure 2021; 9(12): 927-37. 
 
111 Demko ZO, Yu T, Mullapudi SK, et al. Post-acute sequelae of SARS-CoV-2 (PASC) impact 
quality of life at 6, 12, and 18 months post-infection. medRxiv 2022: 2022.08.08.22278543. 
 
112 Cairns R, Hotopf M. A systematic review describing the prognosis of chronic fatigue syndrome. 
Occupational Medicine 2005; 55(1): 20-31. 
 
113 Bach K. Is ‘long Covid’ worsening the labor shortage? Brookings. Published January 11, 2022. 
 
114 Swank Z, Senussi Y, Manickas-Hill Z, et al. Persistent circulating severe acute respiratory 
syndrome coronavirus 2 spike is associated with post-acute coronavirus disease 2019 sequelae. 
Clinical Infectious Diseases 2023; 76(3): e487-e90. 
 
115 Glynne P, Tahmasebi N, Gant V, Gupta R. Long COVID following mild SARS-CoV-2 infection: 
characteristic T cell alterations and response to antihistamines. Journal of Investigative Medicine 
2022; 70(1): 61-7. 
 
116 Zubchenko S, Kril I, Nadizhko O, Matsyura O, Chopyak V. Herpesvirus infections and post-
COVID-19 manifestations: a pilot observational study. Rheumatology International 2022; 42(9): 
1523-30. 
 
117 Yeoh YK, Zuo T, Lui GC-Y, et al. Gut microbiota composition reflects disease severity and 
dysfunctional immune responses in patients with COVID-19. Gut 2021; 70(4): 698-706. 
 
118 Su Y, Yuan D, Chen DG, et al. Multiple early factors predict post-acute COVID-19 sequelae. 
Cell 2022; 185(5): 881-95. e20. 
 
 

112 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
119 Proal AD, VanElzakker MB. Long COVID or post-acute sequelae of COVID-19 (PASC): an 
overview of biological factors that may contribute to persistent symptoms. Frontiers in 
Microbiology 2021; 12: 1494. 
 
120 Haffke M, Freitag H, Rudolf G, et al. Endothelial dysfunction and altered endothelial biomarkers 
in patients with post-COVID-19 syndrome and chronic fatigue syndrome (ME/CFS). Journal of 
Translational Medicine 2022; 20(1): 1-11. 
 
122  Renz-Polster H, Tremblay M-E, Bienzle D, Fischer JE. The pathobiology of myalgic 
encephalomyelitis/chronic fatigue syndrome: the case for neuroglial failure. Frontiers in Cellular 
Neuroscience 2022: 220. 
 
123 Merzon E, Weiss M, Krone B, et al. Clinical and socio-demographic variables associated with 
the diagnosis of long COVID syndrome in youth: a population-based study. International Journal 
of Environmental Research and Public Health 2022; 19(10): 5993. 
 
124 Ziauddeen N, Gurdasani D, O’Hara ME, et al. Characteristics and impact of Long Covid: 
Findings from an online survey. PloS one 2022; 17(3): e0264331. 
 
125 Williamson AE, Tydeman F, Miners A, Pyper K, Martineau AR. Short-term and long-term impacts 
of COVID-19 on economic vulnerability: a population-based longitudinal study (COVIDENCE 
UK). BMJ Open 2022; 12(8): e065083. 
 
126 Ziauddeen N, Gurdasani D, O’Hara ME, et al. Characteristics and impact of Long Covid: 
Findings from an online survey. PloS one 2022; 17(3): e0264331. 
 
127 Komaroff AL, Lipkin WI. Insights from myalgic encephalomyelitis/chronic fatigue syndrome may 
help unravel the pathogenesis of post-acute COVID-19 syndrome. Trends in Molecular Medicine 
2021; 27(9): 895-906. 
 
128 Jamal SM, Landers DB, Hollenberg SM, et al. Prospective evaluation of autonomic dysfunction 
in post-acute sequelae of COVID-19. Journal of the American College of Cardiology 2022; 
79(23): 2325-30. 
 

113 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
 
129 Roca-Fernández A, Wamil M, Telford A, et al. Cardiac impairment in Long COVID 1 year after 
SARS-CoV-2 infection. medRxiv 2022: 2022.04.03.22272610. 
 
130 Pretorius E, Venter C, Laubscher GJ, et al. Prevalence of symptoms, comorbidities, fibrin 
amyloid microclots, and platelet pathology in individuals with Long COVID/Post-Acute Sequelae 
of COVID-19 (PASC). Cardiovascular Diabetology 2022; 21(1): 148. 
 
131 Grist JT, Collier GJ, Walters H, et al. Lung abnormalities detected with hyperpolarized 129Xe 
MRI in patients with long COVID. Radiology 2022; 305(3): 709-17. 
 
132 Peluso MJ, Deeks SG, Mustapic M, et al. SARS-CoV-2 and mitochondrial proteins in neural-
derived exosomes of COVID-19. Annals of Neurology 2022; 91(6): 772-81. 
 
133 Galán M, Vigón L, Fuertes D, et al. Persistent overactive cytotoxic immune response in a 
Spanish cohort of individuals with long COVID: identification of diagnostic biomarkers. Frontiers 
in Immunology 2022; 13: 1129. 
 
134 Grandjean D, Slama D, Gallet C, et al. Screening for SARS-CoV-2 persistence in long COVID 
patients using sniffer dogs and scents from axillary sweat samples. medRxiv 2022: 
2022.01.11.21268036. 
 
135 Pifarré F, Rosselló L, Hileno R, et al. The use of oxygen as a potential screening biomarker for 
the diagnosis of chronic fatigue. Apunts Sports Medicine 2022; 57(214): 100379. 
 
136 Sacristán-Galisteo C, Del Corral T, Ríos-León M, et al. Construct validity of the Spanish version 
of the Post-COVID-19 Functional Status scale and validation of the web-based form in COVID-
19 survivors. Plos one 2022; 17(6): e0269274. 
 
137 Zheng B, Vivaldi G, Daines L, et al. Determinants of recovery from post-COVID-19 dyspnea: 
analysis of UK prospective cohorts of hospitalized COVID-19 patients and community-based 
controls. The Lancet Regional Health–Europe 2023. 
 
 

114 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
138 Aiello EN, Fiabane E, Manera MR, et al. Screening for cognitive sequelae of SARS-CoV-2 
infection: a comparison between the Mini-Mental State Examination (MMSE) and the Montreal 
Cognitive Assessment (MoCA). Neurological Sciences 2022: 1–4. 
 
139 Eldokla AM, Mohamed-Hussein AA, Fouad AM, et al. Prevalence and patterns of symptoms of 
dysautonomia in patients with long-COVID syndrome: A cross-sectional study. Annals of Clinical 
and Translational Neurology 2022; 9(6): 778-85. 
 
140 Ramos-Usuga D, Perrin PB, Bogdanova Y, et al. Moderate, little, or no improvements in 
neurobehavioral symptoms among individuals with long COVID: a 34-country retrospective 
study. International Journal of Environmental Research and Public Health 2022; 19(19): 12593. 
 
141 Zakia H, Pradana K, Iskandar S. Risk factors for psychiatric symptoms in patients with long 
COVID: A systematic review. Plos one 2023; 18(4): e0284075. 
 
142 Bolton MJ, Chapman BP, Van Marwijk H. Low-dose naltrexone as a treatment for chronic fatigue 
syndrome. BMJ Case Reports CP 2020; 13(1): e232502. 
 
143 Bateman L, Bested AC, Bonilla HF, et al. Myalgic encephalomyelitis/chronic fatigue syndrome: 
essentials of diagnosis and management.  Mayo Clinic Proceedings; 2021: Elsevier; 2021. p. 
2861-78. 
 
144 Pitt B, Tate AM, Gluck D, Rosenson RS, Goonewardena SN. Repurposing low-dose naltrexone 
for the prevention and treatment of immunothrombosis in COVID-19. European Heart Journal-
Cardiovascular Pharmacotherapy 2022; 8(4): 402-5. 
 
145 Hohberger B, Harrer T, Mardin C, et al. Case report: neutralization of autoantibodies targeting 
G-protein-coupled receptors improves capillary impairment and fatigue symptoms after COVID-
19 infection. Frontiers in Medicine 2021: 2008. 
 
146 Wang C, Yu C, Jing H, et al. Long COVID: the nature of thrombotic sequelae determines the 
necessity of early anticoagulation. Frontiers in Cellular and Infection Microbiology 2022; 12. 
 

115 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
 
147 Tölle M, Freitag H, Antelmann M, et al. Myalgic encephalomyelitis/chronic fatigue syndrome: 
efficacy of repeat immunoadsorption. Journal of Clinical Medicine 2020; 9(8): 2443. 
 
148  Wood E, Hall KH, Tate W. Role of mitochondria, oxidative stress, and the response to 
antioxidants in myalgic encephalomyelitis/chronic fatigue syndrome: a possible approach to 
SARS-CoV-2 ‘long-haulers’? Chronic Diseases and Translational Medicine 2021; 7(01): 14-26. 
 
149 Geng LN, Bonilla HF, Shafer RW, Miglis MG, Yang PC. Case report of breakthrough long COVID 
and the use of nirmatrelvir-ritonavir. 2022. 
 
150 Xie Y, Choi T, Al-Aly Z. Nirmatrelvir and the risk of post-acute sequelae of COVID-19. MedRxiv 
2022: 2022.11.03.22281783. 
 
151 Charfeddine S, Hadjamor HI, Torjmen S, et al. Sulodexide in the treatment of patients with long 
COVID-19 symptoms and endothelial dysfunction: the results of the TUN-EndCOV study. 
Archives of Cardiovascular Diseases Supplements 2022; 14(1): 127. 
 
152 Thomas R, Williams M, Aldous J, et al. A randomized, double-blind, placebo-controlled trial 
evaluating a concentrated phytochemical-rich nutritional capsule in addition to a probiotic 
capsule on clinical outcomes among individuals with COVID-19—the UK Phyto-V study. COVID 
2022; 2(4): 433-49. 
 
153 Crooks V, Waller S, Smith T, Hahn TJ. The use of the Karnofsky Performance Scale in 
determining outcomes and risk in geriatric outpatients. Journal of Gerontology 1991; 46(4): 
M139-M44. 
 
154 Ledford H. Long-COVID treatments: why the world is still waiting. Nature 2022; 608(7922): 258-
60. 
 
155 Toogood PL, Clauw DJ, Phadke S, Hoffman D. Myalgic encephalomyelitis/chronic fatigue 
syndrome (ME/CFS): Where will the drugs come from? Pharmacological Research 2021; 165: 
105465. 
 

116 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
 
156 Narita N, Hashimoto K, Tomitaka S, Minabe Y. Interactions of selective serotonin reuptake 
inhibitors with subtypes of sigma receptors in rat brain. Eur J Pharmacol. 1996;307(1):117-119. 
 
157 Delprat B, Crouzier L, Su TP, Maurice T. At the Intersection of ER Stress and MAMs: A Key 
Role for the Sigma-1 Receptor? Adv Exp Med Biol. 2020;1131:699-718. 
 
158 Mori T, Hayashi T, Hayashi E, Su TP. Sigma-1 receptor chaperone at the ER-mitochondrion 
interface mediates the mitochondrion-ER-nucleus signaling for cellular survival. PLoS One. 
2013;8(10):e76941 
 
159 Rosen DA, Seki SM, Fernandez-Castaneda A, et al. Modulation of the sigma-1 receptor-IRE1 
pathway is beneficial in preclinical models of inflammation and sepsis. Sci Transl Med. 
2019;11(478). 
 
160 Hoffmann M, Kleine-Weber H, Schroeder S, et al. SARS-CoV-2 cell entry depends on ACE2 
and TMPRSS2 and is blocked by a clinically proven protease inhibitor. Cell. 2020;181(2):271-
280 and 278 
 
161  Knoops K, Kikkert M, Worm SH, et al. SARS-coronavirus replication is supported by a 
reticulovesicular network of modified endoplasmic reticulum. PLoS Biol. 2008;6(9):e226. 
 
162 Gassen NC, Papies J, Bajaj T, et al. Analysis of SARS-CoV-2-controlled autophagy reveals 
spermidine, MK-2206, and niclosamide as putative antiviral therapeutics. bioRxiv. 
2020:2020.2004.2015.997254. 
 
163 Laurent EMN, Sofianatos Y, Komarova A, et al. Global BioID-based SARS-CoV-2 protein 
proximal interactome unveils novel ties between viral polypeptides and host factors involved in 
multiple COVID-19-associated mechanisms. bioRxiv. 2020:2020.2008.2028.272955 
 
164 Gordon DE, Jang GM, Bouhaddou M, et al. A SARS-CoV-2 protein interaction map reveals 
targets for drug repurposing. Nature. 2020;583(7816):459-468. 
 
 

117 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
165 Yang H, Shen H, Li J, Guo LW. SIGMAR1/Sigma-1 receptor ablation impairs autophagosome 
clearance. Autophagy. 2019;15(9):1539-1557. 
 
166 Gorshkov K, Chen CZ, Bostwick R, et al. The SARS-CoV-2 cytopathic effect is blocked by 
autophagy modulators. bioRxiv: the preprint server for biology. 2020:2020.2005.2016.091520. 
 
167 Homolak J, Kodvanj I. Widely available lysosome-targeting agents should be considered as 
potential therapies for COVID-19. Int J Antimicrob Agents. 2020;56(2):106044. 
 
168 Daniel WA, Wojcikowski J. Contribution of lysosomal trapping to the total tissue uptake of 
psychotropic drugs. Pharmacol Toxicol. 1997;80(2):62-68. 
 
169 Fung TS, Liu DX. The ER stress sensor IRE1 and MAP kinase ERK modulate autophagy 
induction in cells infected with infectious bronchitis virus. Virology. 2019;533:34-44. 
 
170 Kornhuber J, Tripal P, Gulbins E, Muehlbacher M. Functional inhibitors of acid sphingomyelinase 
(FIASMAs). Handb Exp Pharmacol. 2013(215):169-186. 
 
171 Breiden B, Sandhoff K. Emerging mechanisms of drug-induced phospholipidosis. Biol Chem. 
2019;401(1):31-46. 
 
172 Chan SW. The unfolded protein response in viral infections. Front Microbiol. 2014;5:518. 
 
173  Jheng JR, Ho JY, Horng JT. ER stress, autophagy, and RNA viruses. Front Microbiol. 
2014;5:388. 
 
174 Nabirotchkin S, Peluffo AE, Bouaziz J, Cohen D. Focusing on the Unfolded Protein Response 
and Autophagy-Related Pathways to Reposition Common Approved Drugs against COVID-19. 
Preprints. 2020. 
 
175 Hosszu A, Antal Z, Lenart L, et al. Sigma-1 Receptor Agonism Protects against Renal Ischemia-
Reperfusion Injury. J Am Soc Nephrol. 2017;28(1):152-165. 
 
 

118 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
176 Tagashira H, Bhuiyan MS, Fukunaga K. Diverse regulation of IP3 and ryanodine receptors by 
pentazocine through the sigma1 receptor in cardiomyocytes. Am J Physiol Heart Circ Physiol. 
2013;305(8):H1201-1212. 
 
177 Manne BK, Denorme F, Middleton EA, et al. Platelet gene expression and function in patients 
with COVID-19. Blood. 2020;136(11):1317-1329. 
 
178 Schlienger RG, Meier CR. Effect of selective serotonin reuptake inhibitors on platelet activation: 
can they prevent acute myocardial infarction? Am J Cardiovasc Drugs. 2003;3(3):149-162. 
 
179 Van den Berg DF, Te Velde AA. Severe COVID-19: NLRP3 Inflammasome Dysregulated. Front 
Immunol. 2020;11:1580. 
 
180 Ratajczak MZ, Kucia M. SARS-CoV-2 infection and overactivation of the NLRP3 inflammasome 
as a trigger of cytokine "storm" and a risk factor for damage to hematopoietic stem cells. 
Leukemia. 2020;34(7):1726-1729. 
 
181 Garcia JA, Volt H, Venegas C, et al. Disruption of the NF-κB/NLRP3 connection by melatonin 
requires retinoid-related orphan receptor-alpha and blocks the septic response in mice. FASEB 
J. 2015;29(9):3863-3875. 
 
182 Volt H, Garcia JA, Doerrier C, et al. Same molecule but different expression: aging and sepsis 
trigger NLRP3 inflammasome activation, a target of melatonin. J Pineal Res. 2016;60(2):193-
205. 
 
183  Hartter S, Wang X, Weigmann H, et al. Differential effects of fluvoxamine and other 
antidepressants 
on 
the 
biotransformation 
of 
melatonin. 
J 
Clin 
Psychopharmacol. 
2001;21(2):167-174. 
 
184 Sukhatme VP, Reiersen AM, Vayttaden SJ, Sukhatme VV. Fluvoxamine: A Review of Its 
Mechanism of Action and Its Role in COVID-19. Front Pharmacol. 2021 Apr 20;12:652688. doi: 
10.3389/fphar.2021.652688. 
 
 

119 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
185 Lenze EJ, Mattar C, Zorumski CF, Stevens A, Schweiger J, Nicol GE, Miller JP, Yang L, Yingling 
M, Avidan MS, Reiersen AM. Fluvoxamine vs Placebo and Clinical Deterioration in Outpatients 
With Symptomatic COVID-19: A Randomized Clinical Trial. JAMA. 2020 Dec 8;324(22):2292-
2300. doi: 10.1001/jama.2020.22760. 
 
186 Reis G, Dos Santos Moreira-Silva EA, Silva DCM, et al. TOGETHER investigators. Effect of 
early treatment with fluvoxamine on risk of emergency care and hospitalization among patients 
with COVID-19: the TOGETHER randomized, platform clinical trial. Lancet Glob Health. 2021 
Oct 27:S2214-109X(21)00448-4. doi: 10.1016/S2214-109X(21)00448-4. 
 
 
187 Reis G, Dos Santos Moreira Silva EA, Medeiros Silva DC et al. TOGETHER Investigators. Oral 
Fluvoxamine With Inhaled Budesonide for Treatment of Early-Onset COVID-19: A Randomized 
Platform Trial. Ann Intern Med. May 2023;176(5):667-675. doi: 10.7326/M22-3305.  
 
188 Sidky H, Sahner DK, Girvin AT et al. Assessing the Effect of Selective Serotonin Reuptake 
Inhibitors in the Prevention of Post-Acute Sequelae of COVID-19. medRxiv [Preprint]. 2023 Feb 
10:2022.11.09.22282142. doi: 10.1101/2022.11.09.22282142.  
 
189  Farahani RH, Ajam A, Naeini AR. Effect of fluvoxamine on preventing neuropsychiatric 
symptoms of post-COVID syndrome in mild to moderate patients: a randomized, placebo-
controlled, double-blind clinical trial. BMC Infect Dis. 2023 Mar 31;23(1):197. doi: 
10.1186/s12879-023-08172-5. 
190 Simonnet A, Chetboun M, Poissy J, et al. High prevalence of obesity in severe acute respiratory 
syndrome coronavirus-2 (SARS-CoV-2) patients requiring invasive mechanical ventilation. 
Obesity 2020; 28: 1195–99. 
 
191  Bosch TA, Steinberger J, Sinaiko AR, et al. Identification of sex-specific thresholds for 
accumulation of visceral adipose tissue in adults. Obesity 2015; 23: 375–82. 
 
192 Zhu L, She Z-G, Cheng X, et al. Association of blood glucose control and outcomes in patients 
with COVID-19 and pre-existing type 2 diabetes. Cell Metabolism 2020; 31(6): 1068–77. e3. 
 
 

120 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
193 Jadhav S, Ferrell W, Greer IA, Petrie JR, Cobbe SM, Sattar N. Effects of metformin on 
microvascular function and exercise tolerance in women with angina and normal coronary 
arteries: a randomized, double-blind, placebo-controlled study. Journal of the American College 
of Cardiology 2006; 48(5): 956-63. 
 
194 Ackermann M, Verleden SE, Kuehnel M, et al. Pulmonary vascular endothelialitis, thrombosis, 
and angiogenesis in Covid-19. New England Journal of Medicine 2020; 383(2): 120-8. 
 
195 Xin G, Wei Z, Ji C, et al. Metformin uniquely prevents thrombosis by inhibiting platelet activation 
and mtDNA release. Scientific Reports 2016; 6(1): 36222. 
 
196 Levi M, Thachil J, Iba T, Levy JH. Coagulation abnormalities and thrombosis in patients with 
COVID-19. The Lancet Haematology 2020; 7(6): e438-e40. 
 
197 Cameron AR, Morrison VL, Levin D, et al. Anti-inflammatory effects of metformin irrespective of 
diabetes status. Circulation Research 2016; 119(5): 652-65. 
 
198 Almeida VH, Rondon AM, Gomes T, Monteiro RQ. Novel aspects of extracellular vesicles as 
mediators of cancer-associated thrombosis. Cells 2019; 8(7): 716. 
 
199 Richardson S, Hirsch JS, Narasimhan M, et al. Presenting characteristics, comorbidities, and 
outcomes among 5,700 patients hospitalized with COVID-19 in the New York City area. JAMA 
2020; 323(20): 2052-9. 
 
200 Bray GA. Medical consequences of obesity. J Clin Endocrinol Metab 2004; 89: 2583–89. 
 
201  Tufan A, Avanoğlu Güler A, Matucci-Cerinic M. COVID-19, immune system response, 
hyperinflammation, and repurposing of antirheumatic drugs. Turk J Med Sci 2020; 50: 620–32. 
 
202 Blüher M, Fasshauer M, T.njes A, Kratzsch J, Sch.n MR, Paschke R. Association of interleukin-
6, C-reactive protein, interleukin-10, and adiponectin plasma concentrations with measures of 
obesity, insulin sensitivity, and glucose metabolism. Exp Clin Endocrinol Diabetes 2005; 113: 
534–37. 
 

121 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
 
203 Matsiukevich D, Piraino G, Lahni P, et al. Metformin ameliorates gender- and age-dependent 
hemodynamic instability and myocardial injury in murine hemorrhagic shock. Biochim Biophys 
Acta Mol Basis Dis 2017; 1863: 2680–91. 
 
204 Quan H, Zhang H, Wei W, Fang T. Gender-related differences in the effects of a combined 
therapy of exenatide and metformin on overweight or obese patients with type 2 diabetes 
mellitus. J Diabetes Complications 2016; 30: 686–92. 
 
205 Park JW, Lee JH, Park YH, et al. Sex-dependent difference in the effect of metformin on 
colorectal cancer-specific mortality in diabetic colorectal cancer patients. World J Gastroenterol 
2017; 23: 5196–205. 
 
206 Chen X, Guo H, Qiu L, Zhang C, Deng Q, Leng Q. Immunomodulatory and Antiviral Activity of 
Metformin and Its Potential Implications in Treating Coronavirus Disease 2019 and Lung Injury. 
Front Immunol. 2020 Aug 18;11:2056. doi: 10.3389/fimmu.2020.02056. 
 
207 Ingraham NE, Lotfi-Emran S, Thielen BK, et al. Immunomodulation in COVID-19. The Lancet 
Respiratory Medicine 2020; 8(6): 544-6. 
 
208 Mehta P, McAuley DF, Brown M, Sanchez E, Tattersall RS, Manson JJ. COVID-19: consider 
cytokine storm syndromes and immunosuppression. The Lancet 2020; 395(10229): 1033-4. 
 
209 Chen R, Sang L, Jiang M, et al. Longitudinal hematologic and immunologic variations associated 
with the progression of COVID-19 patients in China. Journal of Allergy and Clinical Immunology 
2020; 146(1): 89-100. 
 
210 Saenwongsa W, Nithichanon A, Chittaganpitch M, et al. Metformin-induced suppression of IFN-
α via mTORC1 signaling following seasonal vaccination is associated with impaired antibody 
responses in type 2 diabetes. Scientific Reports 2020; 10(1): 3229. 
 
211 Van Der Made CI, Simons A, Schuurs-Hoeijmakers J, et al. Presence of genetic variants among 
young men with severe COVID-19. JAMA 2020; 324(7): 663-73. 
 

122 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
 
212 Wang HC, Huang SK. Metformin inhibits IgE- and aryl hydrocarbon receptor-mediated mast cell 
activation in vitro and in vivo. European Journal of Immunology 2018; 48(12): 1989-96. 
 
213 Mackey E, Ayyadurai S, Pohl CS, D’Costa S, Li Y, Moeser AJ. Sexual dimorphism in the mast 
cell transcriptome and the pathophysiological responses to immunological and psychological 
stress. Biology of Sex Differences 2016; 7(1): 1-19. 
 
214  Scheen AJ. Metformin and COVID-19: From cellular mechanisms to reduced mortality. 
Diabetes Metab. 2020 Nov;46(6):423-426. doi: 10.1016/j.diabet.2020.07.006. 
 
215 Luo P, Qiu L, Liu Y, et al. Metformin treatment was associated with decreased mortality in 
COVID-19 patients with diabetes in a retrospective analysis. Am J Trop Med Hyg 2020; 103: 
69–72. 
 
216 Cariou B, Hadjadj S, Wargny M, et al. Phenotypic characteristics and prognosis of inpatients 
with COVID-19 and diabetes: the CORONADO study. Diabetologia 2020; 63: 1500–15. 
 
217  Pérez-Belmonte LM, Torres-Peña JD, López-Carmona MD. Mortality and other adverse 
outcomes in patients with type 2 diabetes mellitus admitted for COVID-19 in association with 
glucose-lowering drugs: a nationwide cohort study. BMC Med. 2020 Nov 16;18(1):359. doi: 
10.1186/s12916-020-01832-2. 
 
218 Bramante CT, Ingraham NE, Murray TA. Metformin and risk of mortality in patients hospitalized 
with COVID-19: a retrospective cohort analysis. Lancet Health Longevity 2020 Dec 3, S2666-
7568 (20) 30033-7. doi: https://doi.org/10.1016/S2666-7568(20)30033-7 
 
219 Reis G, Dos Santos Moreira Silva EA, Medeiros Silva DC et al. Effect of early treatment with 
metformin on risk of emergency care and hospitalization among patients with COVID-19: The 
TOGETHER randomized platform clinical trial. Lancet Reg Health Am. 2022 Feb;6:100142. doi: 
10.1016/j.lana.2021.100142. 
 
 

123 
 
 
 
REVIVE_TOGETHER COVID Long-Term 
 
                         
 
    Clinical Protocol 
V2.0 – April 11, 2024   
 
Total pages: 123 
 
 
220 Bramante CT, Huling JD, Tignanelli CJ et al. Randomized Trial of Metformin, Ivermectin, and 
Fluvoxamine 
for 
Covid-19. 
N 
Engl 
J 
Med. 
2022 
Aug 
18;387(7):599-610. 
doi: 
10.1056/NEJMoa2201662. 
 
221 Bramante CT, Buse JB, Liebovitz D et al. Outpatient treatment of Covid-19 with metformin, 
ivermectin, and fluvoxamine and the development of Long Covid over 10-month follow-up. 
medRxiv [Preprint]. 2022 Dec 23:2022.12.21.22283753. doi: 10.1101/2022.12.21.22283753. 
 
222 Park JJ, Mogg R, Smith GE, et al. How COVID-19 has fundamentally changed clinical research 
in global health. The Lancet Global Health 2021; 9(5): e711-e20. 
 
223 Woodcock J, LaVange LM. Master protocols to study multiple therapies, multiple diseases, or 
both. New England Journal of Medicine 2017; 377(1): 62-70. 
 
224  Adaptive platform trials: definition, design, conduct, and reporting considerations. Nature 
Reviews Drug Discovery 2019; 18(10): 797-807. 
 
225 Morris ZS, Wooding S, Grant J. The answer is 17 years, what is the question: understanding 
time lags in translational research. Journal of the Royal Society of Medicine 2011; 104(12): 510-
20. 
 
226 Rayner CR, Dron L, Park JJ, et al. Accelerating clinical evaluation of repurposed combination 
therapies for COVID-19. The American Journal of Tropical Medicine and Hygiene 2020; 103(4): 
1364. 
 
227 Ursini F, Russo E, Pellino G, et al. Metformin and autoimmunity: a “new deal” for an old drug. 
Frontiers in Immunology 2018; 9: 1236. 
 
228 International Council for Harmonisation of Technical Requirements for Pharmaceuticals for 
Human Use (ICH).  Integrated addendum to ICH E6(R1): guideline for good clinical practice. 
ICH Harmonised Guideline 2016 Nov 9. 
 
229 World Medical Association Declaration of Helsinki. Ethical principles for medical research 
involving human subjects. Oct. 2013.