CompletedNCT04447131Updated Apr 25, 2025

Effect of COVID-19 on Platelet Aggregation

An observational study in COVID-19 and SARS-CoV-2, sponsored by University of Sao Paulo. Completed at 2 sites in Brazil. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-04-25.

Sponsored by University of Sao Paulo · Observational

Study type: Observational
Model: Case-control
Time perspective: Prospective
Enrollment: 120
Ages: 18 Years and older
Sex: All

Study summary

This is a mechanistic, observational, prospective, case and control study, to compare platelet aggregation, analyzed by Multiplate-ADP, in hospitalized patients diagnosed with COVID-19 versus healthy controls. Thus will be included 60 patients who present with respiratory symptoms within 72 hours of hospitalization and confirmation of the diagnosis of COVID-19 by laboratory method (RT -PCR and / or positive serology for SARS-CoV-2 - COVID group); this group will be compared to 60 healthy individuals (asymptomatic and with negative SARS-CoV-2 serology), matched by sex and age to the previous group.

Read the detailed description

There is strong evidence that SARS-CoV-2 infection is associated with atherothrombotic phenomena. However, platelet activity in COVID-19 has not yet been studied.

Thus, the main objective of this project is to evaluate platelet aggregation by the Multiplate-ADP method in hospitalized patients diagnosed with COVID-19, in comparison with the platelet aggregation evaluated by the same method in healthy controls.

Secondary objectives include the assessment of parameters related to coagulation, inflammation, and clinical outcome variables.

This is a mechanistic, observational, prospective, case and control study, which will include 60 patients who present with respiratory symptoms within 72 hours of hospitalization and confirmation of the diagnosis of COVID-19 by laboratory method (RT -PCR and / or positive serology for SARS-CoV-2 - COVID group); this group will be compared to 60 healthy individuals (asymptomatic and with negative SARS-CoV-2 serology), matched by sex and age to the previous group.

Conditions studied

COVID-19
SARS-CoV-2

Browse trials for

COVID-19 7,640

Keywords

Platelet aggreggation
COVID-19
SARS-CoV-2
Multiplate

In context

COVID-19

7,640 studies on the registry are indexed under COVID-19; 488 are open to participants now.

This study's enrollment of 120 is below the median of 261 across 3,136 observational studies indexed under COVID-19.

Browse COVID-19 studies →

Lead sponsor

University of Sao Paulo is the lead sponsor of 1,005 studies on the registry; 90 are open to participants now.

Of its 7 completed or terminated interventional studies of FDA-regulated products, 0 (0%) have results posted.

Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: 18 Years and older
Sexes eligible: All
Accepts healthy volunteers: Yes
Sampling method: Non-probability sample

Study population

Patients with up to 72 hours of hospitalization for respiratory symptoms, tested with RT- PCR for respiratory viruses, will be evaluated for inclusion. Patients with diagnostic criteria for COVID-19 will be considered a case group (COVID-19 group) and will be compared to two other groups: patients hospitalized for respiratory symptoms with a negative test for SARS-CoV-2, and healthy control group.

Inclusion criteria

Agreement to sign the Free and Informed Consent Form (ICF).
Case group: patients with up to 72 hours of hospitalization for respiratory symptoms.
Control group: healthy volunteers, defined as having no history (confirmed or suspected) of COVID-19 or chronic diseases (except hypertension, obesity, dyslipidemia)

Exclusion criteria

Exclusion Criteria:

Known platelet dysfunction or platelet count \<100,000 / µL or> 450,000 / µL;
Terminal illness;
Known liver disease or clotting disorder;
Hematocrit less than 34% or greater than 55%;
Previous use of antiplatelet agents and / or anticoagulants (except acetylsalicylic acid and prophylactic heparin);
Patients on invasive mechanical ventilation or receiving high oxygen flow.

Study design

Observational model: Case-control
Time perspective: Prospective
Enrollment: 120 participants (actual)
Patient registry: No

Groups and cohorts

COVID-19
Confirmation of the diagnosis of COVID-19 by laboratory method (RT-PCR and / or positive serology for SARS-CoV-2 - COVID group).
Other: venipuncture in peripheral vein
Healthy Individuals
Asymptomatic and with negative SARS-CoV-2 serology
Other: venipuncture in peripheral vein
Respiratory symptoms but negative for COVID-19
Negative for SARS-CoV-2. But with respiratory symptoms
Other: venipuncture in peripheral vein

Interventions

Othervenipuncture in peripheral vein
single vacuum venipuncture in peripheral vein

What researchers measure

Primary outcomes

Platelet aggregation analyzed by Multiplate-ADP
Compare platelet aggregation analyzed by Multiplate-ADP in hospitalized patients diagnosed with COVID-19 versus healthy controls.
Time frame: at inclusion

Secondary outcomes

Platelet aggregation by Multiplate-ASPI and Multiplate-TRAP in patients hospitalized for COVID-19 versus healthy controls.
Compare platelet aggregation by Multiplate-ASPI and Multiplate-TRAP in patients hospitalized for COVID-19 versus healthy controls.
Time frame: at inclusion
Reticulated platelet fraction in patients hospitalized for COVID-19 versus healthy controls.
Compare the levels of the reticulated platelet fraction in patients hospitalized for COVID-19 versus healthy controls.
Time frame: at inclusion
Platelet aggregation for COVID-19 versus patients hospitalized for respiratory symptoms but negative for COVID-19.
Compare platelet aggregation by Multiplate-ADPMultiplate-ASPI and Multiplate-TRAP in patients hospitalized for COVID-19 versus patients hospitalized for respiratory symptoms but negative for COVID-19.
Time frame: at inclusion,
Reticulated platelet fraction in patients hospitalized for COVID-19 versus patients hospitalized for respiratory symptoms but negative for COVID-19 research.
Compare the levels of the reticulated platelet fraction in patients hospitalized for COVID-19 versus patients hospitalized for respiratory symptoms but negative for COVID-19.
Time frame: at inclusion
Platelet aggregation in patients hospitalized for COVID-19 versus patients hospitalized for Influenza.
Compare platelet aggregation by Multiplate-ADP, Multiplate-ASPI and Multiplate-TRAP in patients hospitalized for COVID-19 versus patients hospitalized for Influenza.
Time frame: at inclusion
Reticulated platelet fraction in patients hospitalized for COVID-19 versus patients hospitalized for Influenza.
Compare the levels of the reticulated platelet fraction in patients hospitalized for COVID-19 versus patients hospitalized for Influenza.
Time frame: at inclusion
Platelete aggreggation versus composite outcome of death from any cause, thrombotic events, need for ICU, need for intubation during hospitalization
Compare the levels of platelet aggregation (by Multiplate ADP, ASPI and TRAP) in patients with or without the composite outcome of death from any cause, thrombotic events, need for ICU, need for intubation during hospitalization Compare the levels of platelet aggregation (by Multiplate ADP, ASPI and TRAP) in patients with or without the composite outcome of death from any cause, thrombotic events, need for ICU, need for intubation during hospitalization
Time frame: at inclusion
Reticulated platelet fraction versus composite outcome of death from any cause, thrombotic events, need for ICU, need for intubation during hospitalization
Compare the levels of the reticulated platelet fraction in patients with or without the composite outcome of death from any cause, thrombotic events, need for ICU, need for intubation during hospitalization;
Time frame: at inclusion
Platelet aggregation versus time (days) of total hospitalization and in the ICU
Compare the levels of platelet aggregation (by Multiplate ADP, ASPI and TRAP) with the time (days) of total hospitalization and in the ICU;
Time frame: at inclusion
Reticulated platelet fraction versus time (days) of total hospitalization and in the ICU
Correlate the levels of the reticulated platelet fraction with the time (days) of total hospitalization and in the ICU;
Time frame: at inclusion

Study locations

2 sites

Instituto do Coracao (InCor), Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo
Sao Paulo, 05403-900, Brazil
Instituto de infectologia Emílio Ribas
São Paulo, Brazil

References and documents

Publications

Kwong JC, Schwartz KL, Campitelli MA, Chung H, Crowcroft NS, Karnauchow T, Katz K, Ko DT, McGeer AJ, McNally D, Richardson DC, Rosella LC, Simor A, Smieja M, Zahariadis G, Gubbay JB. Acute Myocardial Infarction after Laboratory-Confirmed Influenza Infection. N Engl J Med. 2018 Jan 25;378(4):345-353. doi: 10.1056/NEJMoa1702090. PubMed 29365305 ↗
Hottz ED, Bozza FA, Bozza PT. Platelets in Immune Response to Virus and Immunopathology of Viral Infections. Front Med (Lausanne). 2018 Apr 30;5:121. doi: 10.3389/fmed.2018.00121. eCollection 2018. PubMed 29761104 ↗
McNicol A, Israels SJ. Beyond hemostasis: the role of platelets in inflammation, malignancy and infection. Cardiovasc Hematol Disord Drug Targets. 2008 Jun;8(2):99-117. doi: 10.2174/187152908784533739. PubMed 18537597 ↗
Corrales-Medina VF, Madjid M, Musher DM. Role of acute infection in triggering acute coronary syndromes. Lancet Infect Dis. 2010 Feb;10(2):83-92. doi: 10.1016/S1473-3099(09)70331-7. PubMed 20113977 ↗
Rondina MT, Brewster B, Grissom CK, Zimmerman GA, Kastendieck DH, Harris ES, Weyrich AS. In vivo platelet activation in critically ill patients with primary 2009 influenza A(H1N1). Chest. 2012 Jun;141(6):1490-1495. doi: 10.1378/chest.11-2860. Epub 2012 Mar 1. PubMed 22383669 ↗
Le VB, Schneider JG, Boergeling Y, Berri F, Ducatez M, Guerin JL, Adrian I, Errazuriz-Cerda E, Frasquilho S, Antunes L, Lina B, Bordet JC, Jandrot-Perrus M, Ludwig S, Riteau B. Platelet activation and aggregation promote lung inflammation and influenza virus pathogenesis. Am J Respir Crit Care Med. 2015 Apr 1;191(7):804-19. doi: 10.1164/rccm.201406-1031OC. PubMed 25664391 ↗
Zhou F, Yu T, Du R, Fan G, Liu Y, Liu Z, Xiang J, Wang Y, Song B, Gu X, Guan L, Wei Y, Li H, Wu X, Xu J, Tu S, Zhang Y, Chen H, Cao B. Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study. Lancet. 2020 Mar 28;395(10229):1054-1062. doi: 10.1016/S0140-6736(20)30566-3. Epub 2020 Mar 11. PubMed 32171076 ↗
Zheng YY, Ma YT, Zhang JY, Xie X. COVID-19 and the cardiovascular system. Nat Rev Cardiol. 2020 May;17(5):259-260. doi: 10.1038/s41569-020-0360-5. PubMed 32139904 ↗
Wang D, Hu B, Hu C, Zhu F, Liu X, Zhang J, Wang B, Xiang H, Cheng Z, Xiong Y, Zhao Y, Li Y, Wang X, Peng Z. Clinical Characteristics of 138 Hospitalized Patients With 2019 Novel Coronavirus-Infected Pneumonia in Wuhan, China. JAMA. 2020 Mar 17;323(11):1061-1069. doi: 10.1001/jama.2020.1585. PubMed 32031570 ↗
Levey AS, Bosch JP, Lewis JB, Greene T, Rogers N, Roth D. A more accurate method to estimate glomerular filtration rate from serum creatinine: a new prediction equation. Modification of Diet in Renal Disease Study Group. Ann Intern Med. 1999 Mar 16;130(6):461-70. doi: 10.7326/0003-4819-130-6-199903160-00002. PubMed 10075613 ↗
Rubak P, Villadsen K, Hvas AM. Reference intervals for platelet aggregation assessed by multiple electrode platelet aggregometry. Thromb Res. 2012 Sep;130(3):420-3. doi: 10.1016/j.thromres.2012.06.017. Epub 2012 Jul 17. PubMed 22809844 ↗
Bertolin AJ, Dalcoquio TF, Salsoso R, de M Furtado RH, Kalil-Filho R, Hajjar LA, Siciliano RF, Kallas EG, Baracioli LM, Lima FG, Giraldez RR, Cavalheiro-Filho C, Vieira A, Strunz CMC, Giugliano RP, Tantry US, Gurbel PA, Nicolau JC. Platelet Reactivity and Coagulation Markers in Patients with COVID-19. Adv Ther. 2021 Jul;38(7):3911-3923. doi: 10.1007/s12325-021-01803-w. Epub 2021 Jun 4. PubMed 34086266 ↗

Individual participant data

Plan to share: No

Updates

Tracking since Sep 25, 2026

No changes since tracking began. The registry record was last updated on Apr 25, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT04447131
Lead sponsor: University of Sao Paulo
Collaborators: Fundação de Amparo à Pesquisa do Estado de São Paulo
Responsible party: Jose Carlos Nicolau (Director of Coronary Care Unit, University of Sao Paulo) — Principal investigator
First posted: Jun 25, 2020
Start date: Apr 29, 2020
Primary completion: Jun 30, 2020
Completion: Nov 27, 2023
Last update: Apr 25, 2025

Oversight

Data monitoring committee: No
FDA-regulated drug: No
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Apr 2025. You cannot join it, but the record below documents what was studied.

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