Convalescent Plasma in Outpatients With COVID-19 (C3PO)
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ClinicalTrials.gov Identifier: NCT04355767 |
Recruitment Status :
Completed
First Posted : April 21, 2020
Results First Posted : October 19, 2021
Last Update Posted : October 19, 2021
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The overarching goal of this project is to confirm or refute the role of passive immunization as a safe and efficacious therapy in preventing the progression from mild to severe/critical COVID-19 illness and to understand the immunologic kinetics of anti-SARS-CoV-2 antibodies after passive immunization.The primary objective is to determine the efficacy and safety of a single dose of convalescent plasma (CP) for preventing the progression from mild to severe COVID-19 illness. The secondary objective is to characterize the immunologic response to CP administration.
This study will enroll adults presenting to the emergency department (ED) with mild, symptomatic, laboratory-confirmed COVID-19 illness, who are at high risk for progression to severe/critical illness, but who are clinically stable for outpatient management at randomization.
Condition or disease | Intervention/treatment | Phase |
---|---|---|
Covid19 | Biological: Convalescent Plasma Biological: Saline | Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 511 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Double (Participant, Outcomes Assessor) |
Primary Purpose: | Treatment |
Official Title: | Clinical-trial of COVID-19 Convalescent Plasma in Outpatients |
Actual Study Start Date : | August 11, 2020 |
Actual Primary Completion Date : | March 29, 2021 |
Actual Study Completion Date : | March 29, 2021 |

Arm | Intervention/treatment |
---|---|
Experimental: Convalescent Plasma
Participants receive 1 unit of convalescent plasma.
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Biological: Convalescent Plasma
SARS-CoV-2 convalescent plasma with neutralizing SARS-CoV2 antibodies titers of ≥1:160 administered via intravenous (IV) infusion. |
Placebo Comparator: Placebo
Participants receive 1 unit of saline with multivitamin.
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Biological: Saline
Saline with multivitamin administered via intravenous (IV) infusion.. |
- Number of Patients With Disease Progression (Intention-to-treat Population) [ Time Frame: 15 days ]Disease progression defined as death or hospital admission or seeking emergency or urgent care within 15 days of randomization.
- Number of Patients With Disease Progression (Per-protocol Population) [ Time Frame: 15 days ]Disease progression defined as death or hospital admission or seeking emergency or urgent care within 15 days of randomization.
- Worst Severity Rating on the WHO COVID Ordinal Scale for Clinical Improvement During the 30 Days Following Randomization [ Time Frame: 30 days ]
This scale was developed by a special World Health Organization (WHO) committee for quantifying COVID-19 illness severity.
- 1 = Not hospitalized without limitation in activity (no symptoms)
- 2 = Not hospitalized with limitation in activity (continued symptoms)
- 3 = Hospitalized not on supplemental oxygen
- 4 = Hospitalized on supplemental oxygen by mask or nasal prongs
- 5 = Hospitalized on non-invasive ventilation or high flow nasal cannula
- 6 = Hospitalized, intubated and mechanically ventilated
- 7 = Hospitalized, intubated, mechanically ventilated and requiring additional organ support (pressors, renal replacement therapy)
- 8 = Death
- Number of Patients With Worsening of Symptoms at Day 15 as a Measure of Time to Disease Progression [ Time Frame: 15 days ]
Assessed on the COVID Outpatient Ordinal Outcome Scale censored at 15 days after randomization. Scale provides more granular detail for outpatients than the WHO scale (adapted from Harrell and Lindsell, 2020). Worsening of symptoms is defined as any subject admitted to the hospital (level 1), seen in the emergency room (level 2), a patient who reports increased symptoms of 2 levels on the scale over a 24 hour period, or a patient who reports increased symptoms of 1 level observed for a 48 hour period.
COVID Outpatient Ordinal Outcomes Scale
- 1 = patient requires care in the hospital
- 2 = patient requires care in the emergency department or urgent care
- 3 = patient at home with symptoms rated as moderate (defined as fever, shortness of breath, abdominal pain)
- 4 = patient at home with symptoms rated as mild (defined as afebrile, constitutional symptoms (flu-like illness) without shortness
- 5 = patient in their usual state of health
- Number of Hospital-free Days During the 30 Days Following Randomization [ Time Frame: 30 days ]
- All-cause Mortality [ Time Frame: Assessed at 30 days ]

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- One or more symptoms of COVID-19 illness and laboratory-confirmed SARS-CoV-2 infection
- Has at least one study defined risk factor for severe COVID-19 illness
- Clinical team deems stable for outpatient management without supplemental oxygen
- CP available at the site at the time of enrollment
- Duration of symptoms ≤ 7 days at ED presentation
- Informed consent from subject
Exclusion Criteria:
- Age less than 18 years
- Prisoner or ward of the state
- Presumed unable to complete follow-up assessments
- Prior adverse reaction(s) from blood product transfusion
- Receipt of any blood product within the past 120 days
- Treating clinical team unwilling to administer 300 ml fluid
- Enrollment in another interventional trial for COVID-19 illness

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04355767

Principal Investigator: | Clifton W Callaway, MD, PhD | University of Pittsburgh | |
Principal Investigator: | Valerie Durkalski-Mauldin, PhD | Medical University of South Carolina | |
Principal Investigator: | Frederick Korley, MD, PhD | University of Michigan | |
Principal Investigator: | Sharon Yeatts, PhD | Medical University of South Carolina | |
Principal Investigator: | Robert Silbergleit, MD | University of Michigan | |
Principal Investigator: | William Barsan, MD | University of Michigan | |
Study Director: | Kevin Schulman, MD | Stanford University |
Documents provided by Stanford University:
Study Data/Documents: Individual Participant Data Set

Publications of Results:
Responsible Party: | Stanford University |
ClinicalTrials.gov Identifier: | NCT04355767 |
Other Study ID Numbers: |
C3PO 1OT2HL156812-01 ( U.S. NIH Grant/Contract ) |
First Posted: | April 21, 2020 Key Record Dates |
Results First Posted: | October 19, 2021 |
Last Update Posted: | October 19, 2021 |
Last Verified: | October 2021 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Yes |
Plan Description: | The complete de-identified patient data set will be shared. |
Supporting Materials: |
Study Protocol Statistical Analysis Plan (SAP) Informed Consent Form (ICF) |
Time Frame: | Data will be available indefinitely. |
Access Criteria: | Data requests will be managed by National Heart, Lung, and Blood Institute (NHLBI). |
URL: | https://biodatacatalyst.nhlbi.nih.gov/ |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
COVID-19 Respiratory Tract Infections Infections Pneumonia, Viral Pneumonia Virus Diseases |
Coronavirus Infections Coronaviridae Infections Nidovirales Infections RNA Virus Infections Lung Diseases Respiratory Tract Diseases |