Participants, interventions, and outcomes
Participating centers
Study clinical sites included 33 public and private tertiary hospitals across the different regions in Spain. The only requirement for the participating study sites was a local research team that include as co-principal investigators both a hematologist and an infectious diseases or internal medicine investigator, together with participation in the trial of the reference Transfusion Center. Transfusion services or centers at the hospitals or Autonomous Communities and National Army Transfusion Center are essential participants in this trial. ISCIII (Centro Nacional de Microbiología, Instituto de Salud Carlos III) centralized the antibodies and PCR microbiological testing from patients and donors. (Appendix 1)
Eligibility criteria
Eligibility criteria for patients
Inclusion criteria are:
- Written informed consent prior to performing study procedures. Witnessed oral consent will be accepted in order to avoid paper handling, which increased the risk of transmission of the infection. Written consent by patient or representatives will be obtained as soon as possible.
- Male or female adult patient ≥ 18 years of age at the time of enrolment.
- Laboratory-confirmed SARS-CoV-2 infection as determined by PCR in naso/oropharyngeal swabs or any other relevant specimen obtained in the ongoing COVID-19 symptomatic period. Alternative tests (i.e. rapid antigenic tests) are also acceptable as laboratory confirmation if their adequate specificity has been accepted by the sponsor.
- Patients requiring hospitalization for COVID-19 without mechanical ventilation (invasive or non-invasive) or high flow oxygen devices and at least one of the following:- Radiographic evidence of pulmonary infiltrates by imaging (chest x-ray, CT scan, etc.) OR- Clinical assessment (evidence of rales/crackles on exam) and SpO2 ≤ 94% on room air that requires supplemental oxygen.
- No more than 12 days between the onset of symptoms (fever or cough) and treatment administration day. Following 31st August amendment, only patients with no more than 7 days between the onset of symptoms and treatment administration day are allowed for inclusion.
Exclusion criteria are:
- Requiring mechanical ventilation (invasive or non-invasive) or high flow oxygen devices at screening.
- More than 12 days since symptoms (fever or cough) onset.
- Participation in any other clinical trial of an experimental treatment for COVID-19.
- In the opinion of the clinical team, progression to death is imminent and inevitable within the next 24 hours, irrespective of the provision of treatments.
- Any incompatibility or allergy to the administration of human plasma.
- Stage 4 severe chronic kidney disease or requiring dialysis (i.e. eGFR<30).
Eligibility criteria for donors
Inclusion criteria are:
- Subjects willing and able to provide written informed consent.
- Fulfilling all the current requirements to be a plasma apheresis donor according to the regulations for donation of blood products (European Guidelines and RD 1088/2005 in Spain).
- Absence of COVID-19 symptoms within the last 14 days.
- Anti SARS-CoV-2 IgG antibodies detectable in peripheral blood.
- ≥18 years of age at time of donation.
- Weight > 50kg and good vein access are standard criteria, for which exceptions could be considered according to the criteria of the blood bank and hematologist.
Exclusion criteria are:
- Plasmapheresis in the previous seven days.
- Whole blood donation in the previous 30 days.
- Donation of more than 25 liters of plasma in the previous 12 months.
Informed consent
Investigators will obtain the subject’s informed consent in accordance with Spanish Law 14/2007 on Biomedical Investigation and the internationally ethical accepted guidelines.
Patients will receive a concise and focused presentation of key information about the clinical trial, orally, and a written informed consent form will be handled to the patient. Due to paper handling limitation in COVID wards, oral witnessed consent will be accepted before entering into the trial, with written documentation in the patient clinical record. If possible, written consent form will be obtained from the patient himself or acceptable representatives, at a later time.
Donors will receive concise information about the clinical trial and will give written informed consent before donating convalescent plasma.
Additional consent provisions
The consent form includes provisions for research data and residual samples to be stored for future scientific research on COVID-19. These future studies will be previously evaluated by a Research Ethics Committee and will comply with the applicable ethical and legal requirements.
Study interventions
Intervention description
All trial participants will receive SOC for COVID-19. The control arm is SOC for COVID-19. In the treatment arm, patients will also receive intravenous pathogen reduced CP from patients recovered from COVID-19 (designated as donors) as add-on therapy to SOC.
In the current status of a worldwide pandemic for which we have no approved vaccines or drugs, for the purpose of this trial SOC will include any medicinal products being used in clinical practice (e.g. lopinavir/ritonavir; darunavir/cobicistat; hydroxy/chloroquine, tocilizumab, remdesivir, allowed as SOC when its use outside clinical trials was permitted), other than those used as part of another clinical trial.
Donor assessment, pathogen reduced plasma collection and production will be performed by hospital Transfusion Services and Regional Transfusion Centres. Local organization will be adapted to the existing structure at the regional level.
Criteria for discontinuing or modifying allocated interventions
A patient may be removed from the study treatment for the reasons mentioned below, although whenever possible the patient should be followed regardless of their protocol adherence as per the efficacy and safety evaluations:
- Patient withdraws consent or requests discontinuation from the study for any reason
- Termination of the study.
- Lost to follow-up.
Patients who withdraw from this study or are lost to follow-up after signing the informed consent form (ICF) will not be replaced. The reason for patient discontinuation from the study will be recorded on the appropriate case report form.
Strategies to improve adherence to interventions
This item is not applicable, since active agent is administered intravenously by health care professionals in a single dose administration.
Relevant concomitant care permitted or prohibited during the trial
This study seeks to investigate the effects of CP in addition to standard of care. All concomitant care and interventions are permitted other than concomitant administration of any other experimental treatment.
Provisions for post-trial care
No special arrangements for post-trial care are anticipated.
Outcomes
Primary outcome measure
The primary outcome measure is the proportion of patients that progress to categories 5, 6 or 7 (hospitalized severe disease or death categories) on the 7-point ordinal scale recommended in the Master Protocol of the WHO R&D Blueprint expert group, at day 15 (Table 1).

Secondary outcome measures
The secondary outcome measures include:
-Ordinal scale (see 7-point ordinal scale above):
- Status at day 30
- Time to category 5, 6 or 7 of the ordinal scale.
- Time to an improvement of one category from admission on the ordinal scale.
- Time to first deterioration
- Mean change in the ranking on an ordinal scale from baseline to days 3, 5, 8, 11, 15, 29 and 60.
-Ordinal scale of 11 points (Appendix 2):
- Mean change in the ranking on an ordinal scale from baseline to days 3, 5, 8, 11, 15, 29 and 60
- Status at day 15 and 30
-Mortality rate (all cause) at day 15, at day 29, and at day 60
-Oxygenation free days in the first 28 days (day 29).
-Ventilator free days in the first 28 days (day 29).
-Duration of hospitalization (days).
-Incidence of thrombotic arterial events
-Incidence of thrombotic venous events
-Rate of rehospitalizations.
-Serum level of CRP, lymphocyte count, LDH, D Dimer, IL-6, coagulation tests at baseline and at days 3, 5, 8, 11, 15, 29 and 60.
-Safety assessments of CP+SOC as compared to SOC alone through day 60 considering cumulative incidence of serious adverse events (SAEs), cumulative incidence of Grade 3 and 4 adverse events (AEs), and infusion-related adverse reactions.
Exploratory outcomes include the following virology and immunology assessments:
- Qualitative and quantitative RT-PCR for SARS-CoV-2 in nasopharyngeal/oropharyngeal swabs at baseline and at hospital discharge;
- Qualitative and quantitative RT-PCR for SARS-CoV-2 in blood on Days 3, 5, 8, 11, 15, 29 and 60 (while hospitalized), until two of them are negative consecutively;
- Quantitative anti SARS-CoV-2 antibodies level at baseline and on days 8, 15, 29, and 60 (while hospitalized);
- Neutralizing antibodies study in plasma donors and a subset of patients at baseline.
Participant timelines
The schedule of interventions and visits can be found in Figure 2.
Sample size
We propose an open-label, standard of care controlled, randomised (1:1 ratio); clinical trial with stopping boundaries for efficacy and futility at 20%, 40%, 60 and 80% of the final sample size. The statistical design including the sample size and stopping have been calculated using the East validated software v6.5 by Cytel Inc. The stopping boundaries for superiority and inferiority have been calculated using the Rho family Spending functions.
The primary outcome measure is the proportion of patients that progress to categories 5, 6 or 7 (hospitalized with severe disease or death categories of the 7-point ordinal scale), at day 15. With this design, 278 patients (139 per arm) will be required assuming 20% rate in the control group and an absolute reduction of 10% (10% rate in experimental group), with 80% statistical power a 2.5% one-sided alpha level (5% two-sided). Likewise, approximately 140-200 CP donors will be needed.
With regards to the final sample size, it is predefined that a sample size recalculation will be put in place when 60% of the patients with assessed events at day 15 are available and the 3rd analyses are conducted.
Recruitment
Patients with COVID-19 will be recruited at the participating clinical sites.
Assignment of interventions: allocations
Sequence generation
Randomization among the two arms will be 1:1 and will be stratified per center.
The randomization process has been developed using the RERAND system integrated within the RDC Onsite ECRF system based on Oracle.
Concealment mechanism
This open-label trial will use blind randomization of patients in a 1:1 ratio to CP (+SOC) or SOC alone through a centralized system embedded in the eCRF (Oracle Clinical). Baseline clinical data will be entered in the eCRF before the patient can be randomly assigned via the eCRF at 1:1 ratio to receive standard of care with or without CP as add-on therapy. The system will automatically notify the assigned treatment arm at the eCRF screen and will send a confirmatory message at the email with the randomization information.
Implementation
Patients in the treatment arm will receive a single unit of CP (250-300 mL) after randomization on day 1 under control of the patient´s clinician and the Transfusion Service´s hematologist of the hospital.
Pathogen reduced plasma bags will be frozen below -25ºC, and stored and shipped following European guidelines for blood components storage (36 months below -25ºC or 3 months below -18ºC). For transport, plasma bags must be kept frozen. No special containers are needed if plasma units are kept frozen at the delivery.
Assignment of interventions: blinding
This is an open-label study. To reduce treatment bias, the eCRF did not allow randomizing a subject until sufficient clinical information from the subject was already included, reducing the possibility that a given subject could be re-randomized. Additional measures were implemented to reduce assessment bias, e.g. clinical information was collected, and daily clinical decisions were taken by the medical staff at each study center, that in most cases were not part of the research team. The primary endpoint was restricted to WHO scores ≥ 5 in an attempt to not only focus on relevant outcomes, but also to increase the robustness of the endpoint; although some scores are subjected to clinical judgement these are hardly influenced by the clinical trial participation and/or treatment assignment.
Data collection and management
Plans for assessment and collections of outcomes
Investigators are responsible for assessment and collection of outcomes, baseline, and other trial data. Data will be entered in the CRF by delegated team members and will be monitored by the clinical research associated. Subjects will be assessed daily while hospitalized. Patients discharged before the end of follow up will be regularly phoned or asked to attend study visits. NP/OP swabs for virus analysis and blood samples for serological analysis will be sent to a central laboratory, where test will be performed according to laboratory standard operating procedures.
Plans to promote participants retention and complete follow-up
Patients are free to withdraw from participation in the study at any time. The decision must be communicated and reviewed by investigators. Staff at study sites should explain to these subjects the importance of staying in the study for the full duration of follow-up of this trial for safety reasons. The reason for patient discontinuation from the study will be recorded on the appropriate case report form.
In cases where that a patient becomes lost to follow-up, attempts to contact the patient should be made and documented in the patient’s medical records. Patients who withdraw from this study or are lost to follow-up after signing the informed consent form (ICF) and receiving the study product, will not be replaced.
Data management
Data will be examined for compliance with the trial protocol by the monitor and the data manager. Deviations will be sent to the project statistician to plan listings for the Data Review (DR). The objective is to carry out the population selection and definition of the final study populations as well as a preliminary assessment of the quality of the trial data.
All data will be recorded using the defined CRF guidelines for this trial. Also, the blood bank software in each hospital Transfusion Service will be used for recording the plasma units transfused.
Confidentiality
Subject confidentiality is strictly held in trust by the participating investigators, their staff, and the sponsor and their agents. This confidentiality is extended to cover clinical information relating to subjects, test results of biological samples and all other information generated during participation in the study. All study data and research specimens that leave the site (including any electronic transmission of data) will be identified only by a coded number that is linked to a subject through a code key maintained at the clinical site. All source records including electronic data will be stored in secured systems.
No identifiable information concerning subjects in the study will be released to any unauthorized third party. Subject confidentiality will be maintained when study results are published or discussed in conferences. The study monitor, other authorized representatives of the sponsor, representatives of the Research Ethics Committees (RECs), and/or regulatory agencies may inspect all documents and records required to be maintained by the investigator, including but not limited to, medical records (office, clinic, or hospital) for the subjects in this study. The clinical study site will permit access to such records.
Plans for collection, laboratory evaluation, and storage of biological specimens for genetic or molecular analysis in this trial/future use
Samples will be collected by investigators or designees. After that, handling, labeling, processing, storage and/or shipping according to protocol will be performed and the samples will ultimately be sent to the central laboratory.
The Sponsor and the center, may use data and samples for future research projects related with COVID-19, taking the appropriate measures to ensure the protection of their privacy and will not allow their encrypted data to cross with other data bases that could allow their identification. Any future studies will be previously evaluated by a Research Ethics Committee and will comply with the applicable ethical and legal requirements.
Statistical methods
Statistical methods for primary and secondary outcomes
A detailed Statistical Analysis Plan (SAP) agreed upon by the CT Executive Board and the Project Statistician will be available early during the recruitment phase. This SAP will follow the general regulatory recommendations given in the ICHE9 (CPMP/ICH /363/96) guidance, as well as other specific guidance on methodological and statistical issues (8).
Likewise, it will stick to the recommendations given by the consensus documents of the scientific journals to improve reliability and value of medical research literature by promoting transparent and accurate reporting of clinical research studies.
The proportion of patients with failure, defined as categories 5, 6 or 7 of the 7-point ordinal scale at day 15, will be estimated using a log-binomial regression model including stratification variables. In the unexpected event that the model does not fit, the Poisson regression model with long-link and robust variance estimator will be used instead.
Binary efficacy and safety outcomes will be analysed as described for the primary endpoint.
Kaplan-Meier model will be used to analyse survival endpoints (TTF and OS). In all these analyses, in addition to the Kaplan-Meier curve, median, Q1, Q3 and their corresponding 95% CI, number of events and censored cases distribution will be shown. Group comparisons will be done using the (stratified) log-rank test and the (stratified) hazard ratios -HR- (95%CI) from the Cox model.
Interim analyses
Interim analyses for comprehensive efficacy (or futility) and safety data monitoring analyses will be conducted when 20%, 40%, 60% and 80% of patients have been recruited and completed day 15 assessment, or at the discretionary criteria of the DSMB, when needed. The study may be stopped prematurely if either the efficacy or the futility boundaries are crossed. The boundaries will be adapted to the actual information rates in each inspection using the Rho family Spending functions with (rho=7) implemented in the East validated software v6.5 (or later releases) by Cytel Inc. up.
Ad hoc reviews will be undertaken at any time if there are other specific safety concerns. The study will not stop enrolment awaiting these DSMB reviews, though the DSMB may recommend temporary or permanent cessation of enrolment based on their safety reviews.
Methods for additional analyses (e.g. subgroups)
Subgroup analyses will be performed to assess the impact on efficacy of two different key factors, i.e. the level of neutralizing antibodies in the administered plasma and the timing of the disease i.e. early or late stages considering 7 days as cut-off, viral load and IgG or IgM. The following strategy will be conducted before splitting the analysis into subgroups: test of the overall treatment effect, test of the treatment-by-subgroup interaction at the 10% level of significance or test of the treatment effect in each subgroup category
Methods to handle missing data
In principle, the rate of missing data is estimated to be very low due to the type of endpoint, easily available with a fast-clinical assessment, so no impact on the primary analysis is expected. In any case, a very conservative strategy will be implemented consisting of imputing any missing data or other binary efficacy secondary outcomes will be considered to failures, irrespectively to the reason for missingness. With regards to the continuous variables, mixed models ([(9)-(11)]) are robust to the presence of missing at random (MAR) and conducts the analysis with all participants despite the presence of missingness. Of note, this method calculates the estimations based on the variance- covariance structure but without any formal imputations.
Plans to give access to the full protocol, participant-level data, and statistical code
These plans are not yet in place.
Oversight and monitoring
Composition of the coordinating centre and trial steering committee
The study is led by the Hospital Universitario Puerta de Hierro Majadahonda.
The trial steering committee consists of the following members:
- Rafael Duarte, Hematology and Hemotherapy Department. Hospital Universitario Puerta de Hierro Majadahonda
- Cristina Avendaño Solà, Clinical Pharmacology Department. Hospital Universitario Puerta de Hierro Majadahonda
- Antonio Ramos-Martínez, Internal Medicine Department. Infectious diseases Unit. Hospital Universitario Puerta de Hierro Majadahonda
- José Luis Bueno, Hemotherapy & Apheresis Units. Hematology and Hemotherapy Department. Hospital Universitario Puerta de Hierro Majadahonda
- Elena Múñez, Internal Medicine Department. Infectious diseases unit. Hospital Universitario Puerta de Hierro Majadahonda
- Belén Ruiz-Antorán, Clinical Pharmacology Department. Hospital Universitario Puerta de Hierro Majadahonda
- Rosa Malo de Molina, Servicio de Pneumology. Hospital Universitario Puerta de Hierro Majadahonda
- Ferrán Torres, Clinical Pharmacology Department. Hospital Clínic Barcelona. Medical Statistics core facility - IDIBAPS.
- Inmaculada Casas Flecha, Flu and Respiratory Virus Unit. Centro Nacional de Microbiología, Instituto de Salud Carlos III
Trial monitoring
The Spanish Clinical Research Network (SCReN) is responsible for project management, regulatory compliance and trial monitoring.
Data management team
PIVOTAL is the CRO responsible for data management, preparation of the eCRD, quality assurance, and preparation of the SAP.
Composition of the data monitoring committee, its role and reporting structure
The independent DSMB in this study is responsible for reviewing the reports regarding the safety and efficacy of the study patients protocol adherence and making recommendations to continue or terminate the study or to modify the sample size of the basis of the results from the interim analysis. The DSMB members are all independent of the sponsor and have no financial or other conflict of interest.
Adverse event reporting
Serious adverse events (SAEs) and grade 3 or 4 adverse events will be collected from the time of informed consent to day 29. SAEs will be followed up until the SAE has subsided, returned to baseline, or is stable. Infusion-related adverse reactions will be recorded within 24 hours after the end of plasma administration by a trained Hemovigilance nurse or physician, according to the Active 24h quarantine Hemovigilance Program (HEMACUA)
Investigators will be instructed to actively monitor the occurrence of prespecified adverse events of special interest: TRALI (Transfusion-related acute lung injury), ADE (Antibody-dependent enhancement of infection and TACO (Transfusion-associated cardiac overload).
Plans for auditing trial conduct
Monitoring for this study will be performed by the sponsor and SCReN. Monitoring online visits will include, but not limited to, review of regulatory files, accountability records, CRFs, ICFs, medical and laboratory reports, site study intervention storage records, training records, and protocol and GCP compliance.
On site and off-site monitoring, central review of data collection and remote source data verification will be allowed according to EMA and AEMPS guidance/guidelines on the management of clinical trials during the covid-19 (coronavirus) pandemic.
Plans for communicating important protocol amendments to relevant parties (e.g. trial participants, ethical committees)
During the trial, any amendments to the protocol or consent materials will be approved by the REC before they are implemented.
Dissemination plans
Following completion of the study, the results will be published in a scientific journal. Nevertheless, due to the critical need of results during the current epidemic COVID-19 crisis, preliminary results will be released by the sponsor to the Health Authorities.
Ethical and regulatory
The clinical study will be conducted in accordance with the relevant national and international good clinical practice (GCP) guidelines, and the Declaration of Helsinki, each in the applicable version. The study protocol and the donors and the patients ‘written informed consent were submitted to and approved by the Research Ethics Committee of Hospital Puerta de Hierro Majadahonda on March 23th, 2020.