Prospective individual patient data meta-analysis of two randomized trials on convalescent plasma for COVID-19 outpatients

Outpatient randomized controlled trials to reduce COVID-19 hospitalization: Systematic review and meta-analysis

This COVID-19 outpatient randomized controlled trials (RCTs) systematic review compares hospitalization outcomes amongst four treatment classes over pandemic period, geography, variants, and vaccine status. Outpatient RCTs with hospitalization endpoint were identified in Pubmed searches through May 2023, excluding RCTs <30 participants (PROSPERO-CRD42022369181). Risk of bias was extracted from COVID-19-NMA, with odds ratio utilized for pooled comparison. Searches identified 281 studies with 61 published RCTs for 33 diverse interventions analyzed. RCTs were largely unvaccinated cohorts with at least one COVID-19 hospitalization risk factor. Grouping by class, monoclonal antibodies (mAbs) (OR = 0.31 [95% CI = 0.24-0.40]) had highest hospital reduction efficacy, followed by COVID-19 convalescent plasma (CCP) (OR = 0.69 [95% CI = 0.53-0.90]), small molecule antivirals (OR = 0.78 [95% CI = 0.48-1.33]), and repurposed drugs (OR = 0.82 [95% CI: 0.72-0.93]). Earlier in disease onset interventions performed better than later. This meta-analysis allows approximate head-to-head comparisons of diverse outpatient interventions. Omicron sublineages (XBB and BQ.1.1) are resistant to mAbs Despite trial heterogeneity, this pooled comparison by intervention class indicated oral antivirals are the preferred outpatient treatment where available, but intravenous interventions from convalescent plasma to remdesivir are also effective and necessary in constrained medical resource settings or for acute and chronic COVID-19 in the immunocompromised.

Rates Among Hospitalized Patients With COVID-19 Treated With Convalescent Plasma: A Systematic Review and Meta-Analysis

Objective

To examine the association of COVID-19 convalescent plasma transfusion with mortality and the differences between subgroups in hospitalized patients with COVID-19.

Patients and Methods

On October 26, 2022, a systematic search was performed for clinical studies of COVID-19 convalescent plasma in the literature from January 1, 2020, to October 26, 2022. Randomized clinical trials and matched cohort studies investigating COVID-19 convalescent plasma transfusion compared with standard of care treatment or placebo among hospitalized patients with confirmed COVID-19 were included. The electronic search yielded 3841 unique records, of which 744 were considered for full-text screening. The selection process was performed independently by a panel of 5 reviewers. The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Data were extracted by 5 independent reviewers in duplicate and pooled using an inverse-variance random effects model. The prespecified end point was all-cause mortality during hospitalization.

Results

Thirty-nine randomized clinical trials enrolling 21,529 participants and 70 matched cohort studies enrolling 50,160 participants were included in the systematic review. Separate meta-analyses reported that transfusion of COVID-19 convalescent plasma was associated with a decrease in mortality compared with the control cohort for both randomized clinical trials (odds ratio [OR], 0.87; 95% CI, 0.76-1.00) and matched cohort studies (OR, 0.76; 95% CI, 0.66-0.88). The meta-analysis of subgroups revealed 2 important findings. First, treatment with convalescent plasma containing high antibody levels was associated with a decrease in mortality compared with convalescent plasma containing low antibody levels (OR, 0.85; 95% CI, 0.73 to 0.99). Second, earlier treatment with COVID-19 convalescent plasma was associated with a decrease in mortality compared with the later treatment cohort (OR, 0.63; 95% CI, 0.48 to 0.82).

Conclusion

During COVID-19 convalescent plasma use was associated with a 13% reduced risk of mortality, implying a mortality benefit for hospitalized patients with COVID-19, particularly those treated with convalescent plasma containing high antibody levels treated earlier in the disease course.

Quality assessment and harmonization of laboratories across Europe for multiple SARS-CoV-2 serology assays

BACKGROUND AND OBJECTIVES

There is a need for conversion of SARS-CoV-2 serology data from different laboratories to a harmonized international unit. We aimed to compare the performance of multiple SARS-CoV-2 antibody serology assays among 25 laboratories across 12 European countries.

MATERIALS AND METHODS

To investigate this we have distributed to all participating laboratories a panel of 15 SARS-CoV-2 plasma samples and a single batch of pooled plasma calibrated to the WHO IS 20/136 standard.

RESULTS

All assays showed excellent discrimination between SARS-CoV-2 seronegative plasma samples and pre-vaccinated seropositive plasma samples but differed substantially in raw antibody titres. Titres could be harmonized to binding antibody units per millilitre by calibration in relation to a reference reagent.

CONCLUSION

The standardization of antibody quantification is of paramount importance to allow interpretation and comparison of serology data reported in clinical trials in order to identify donor cohorts from whom the most effective convalescent plasma can be collected.

Managing blood supplies during natural disasters, humanitarian emergencies, and pandemics: lessons learned from COVID-19

INTRODUCTION

The COVID-19 pandemic has resulted in a historic public health crisis with widespread social and economic ramifications. The pandemic has also affected the blood supply, resulting in unprecedented and sustained blood shortages.

AREAS COVERED

This review describes the challenges of maintaining a safe and sufficient blood supply in the wake of natural disasters, humanitarian emergencies, and pandemics. The challenges, which are accentuated in low- and high-income countries, span the impact on human capacity (affecting blood donors and blood collections personnel alike), disruption to supply chains, and economic sustainability. COVID-19 imparted lessons on how to offset these challenges, which may be applied to future pandemics and public health crises.

EXPERT OPINION

Pandemic emergency preparedness plans should be implemented or revised by blood centers and hospitals to lessen the impact to the blood supply. Comprehensive planning should address the timely assessment of risk to the blood supply, rapid donor recruitment, and communication of need, measures to preserve safety for donors and operational staff, careful blood management, and resource sharing.

Outpatient regimens to reduce COVID-19 hospitalisations: a systematic review and meta-analysis of randomized controlled trials

Background

During pandemics, early outpatient treatments reduce the health system burden. Randomized controlled trials (RCTs) in COVID-19 outpatients have tested therapeutic agents, but no RCT or systematic review has been conducted comparing the efficacy of the main outpatient treatment classes to each other. We aimed in this systematic review of outpatient RCTs in COVID-19 to compare hospitalisation rate reductions with four classes of treatment: convalescent plasma, monoclonal antibodies, small molecule antivirals and repurposed drugs.

Methods

We conducted a systematic review and meta-analysis of all COVID-19 outpatient RCTs that included the endpoint of progression to hospitalisation. We assembled, from multiple published and preprint databases, participant characteristics, hospitalisations, resolution of symptoms and mortality from January 2020 to May 21, 2023. The risk of bias from COVID-NMA was incorporated into the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. We measured heterogeneity with I 2 . Meta-analysis by a random or fixed effect model dependent on significant heterogeneity (I 2 >50%) was performed. The protocol was registered in PROSPERO, CRD42022369181.

Findings

The search identified 281 studies of which 54 RCTs for 30 diverse interventions were included in the final analysis. These trials, performed largely in unvaccinated cohorts during pre-Omicron waves, focused on populations with at least one COVID-19 hospitalisation risk factor. Grouping by class, monoclonal antibodies (OR=0.31 [95% CI=0.24-0.40]) had highest efficacy, followed by COVID-19 convalescent plasma (CCP) (OR=0.69 [95% CI=0.53 to 0.90]) and small molecule antivirals (OR=0.78 [95% CI=0.48-1.33]) for hospital reduction. Repurposed drugs (OR=0.82 [95% CI-0.72-0.93]) had lower efficacy.

Interpretation

Inasmuch as omicron sublineages (XBB and BQ.1.1) are now resistant to monoclonal antibodies, oral antivirals are the preferred treatment in outpatients where available, but intravenous interventions from convalescent plasma to remdesivir are also effective and necessary in constrained medical resource settings or for acute and chronic COVID-19 in the immunocompromised.

Funding

US Department of Defense and National Institute of Health.

Research in context

Evidence before this study: We systematically searched the published and preprint data bases for outpatient randomized clinical trials of treatment of COVID-19 disease with hospitalisation as an endpoint. Previous systematic reviews and meta-analyses have confined the reviews to specific classes such as convalescent plasma, monoclonal antibodies, small molecule antivirals or repurposed drugs. Few comparisons have been made between these therapeutic classes. The trials took place both in the pre-vaccination and the vaccination era, spanning periods with dominance of different COVID variants. We sought to compare efficacy between the four classes of treatments listed above when used in outpatient COVID-19 patients as shown in randomized, placebo-controlled trials.

Added value of this study

This systematic review and meta-analysis brings together trials that assessed hospitalisation rates in diverse COVID-19 outpatient populations varying in age and comorbidities, permitting us to assess the efficacy of interventions both within and across therapeutic classes. While heterogeneity exists within and between these intervention classes, the meta-analysis can be placed in context of trial diverse populations over variant time periods of the pandemic. At present most of the world population has either had COVID-19 or been vaccinated with a high seropositivity rate, indicating that future placebo-controlled trials will be limited because of the sample sizes required to document hospitalisation outcomes.

Implications of all the available evidence

Numerous diverse therapeutic tools need to be ready for a resilient response to changing SARS-CoV-2 variants in both immunocompetent and immunocompromised COVID-19 outpatient populations. To date few head-to-head randomized controlled trials (RCTs) has compared treatment options for COVID-19 outpatients, making comparisons and treatment choices difficult. This systematic review compares outcomes among RCTs of outpatient therapy for COVID-19, taking into account time between onset of symptoms and treatment administration. We found that small-chemical antivirals, convalescent plasma and monoclonal antibodies had comparable efficacy between classes and amongst interventions within the four classes. Monoclonals have lost efficacy with viral mutation, and chemical antivirals have contraindications and adverse events, while intravenous interventions like convalescent plasma or remdesivir remain resilient options for the immunocompromised, and, in the case of CCP, in resource constrained settings with limited availability of oral drugs.

Therapeutic strategies for COVID-19: progress and lessons learned

The coronavirus disease 2019 (COVID-19) pandemic has stimulated tremendous efforts to develop therapeutic strategies that target severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and/or human proteins to control viral infection, encompassing hundreds of potential drugs and thousands of patients in clinical trials. So far, a few small-molecule antiviral drugs (nirmatrelvir-ritonavir, remdesivir and molnupiravir) and 11 monoclonal antibodies have been marketed for the treatment of COVID-19, mostly requiring administration within 10 days of symptom onset. In addition, hospitalized patients with severe or critical COVID-19 may benefit from treatment with previously approved immunomodulatory drugs, including glucocorticoids such as dexamethasone, cytokine antagonists such as tocilizumab and Janus kinase inhibitors such as baricitinib. Here, we summarize progress with COVID-19 drug discovery, based on accumulated findings since the pandemic began and a comprehensive list of clinical and preclinical inhibitors with anti-coronavirus activities. We also discuss the lessons learned from COVID-19 and other infectious diseases with regard to drug repurposing strategies, pan-coronavirus drug targets, in vitro assays and animal models, and platform trial design for the development of therapeutics to tackle COVID-19, long COVID and pathogenic coronaviruses in future outbreaks.

Early, very high-titre convalescent plasma therapy in clinically vulnerable individuals with mild COVID-19 (COVIC-19): protocol for a randomised, open-label trial

INTRODUCTION

COVID-19 convalescent plasma (CCP) is a possible treatment option for COVID-19. A comprehensive number of clinical trials on CCP efficacy have already been conducted. However, many aspects of CCP treatment still require investigations: in particular (1) Optimisation of the CCP product, (2) Identification of the patient population in need and most likely to benefit from this treatment approach, (3) Timing of administration and (4) CCP efficacy across viral variants in vivo. We aimed to test whether high-titre CCP, administered early, is efficacious in preventing hospitalisation or death in high-risk patients.

METHODS AND ANALYSIS

COVIC-19 is a multicentre, randomised, open-label, adaptive superiority phase III trial comparing CCP with very high neutralising antibody titre administered within 7 days of symptom onset plus standard of care versus standard of care alone. We will enrol patients in two cohorts of vulnerable patients [(1) elderly 70+ years, or younger with comorbidities; (2) immunocompromised patients]. Up to 1020 participants will be enrolled in each cohort (at least 340 with a sample size re-estimation after reaching 102 patients). The primary endpoint is the proportion of participants with (1) Hospitalisation due to progressive COVID-19, or (2) Who died by day 28 after randomisation. Principal analysis will follow the intention-to-treat principle.

ETHICS AND DISSEMINATION

Ethical approval has been granted by the University of Ulm ethics committee (#41/22) (lead ethics committee for Germany), Comité de protection des personnes Sud-Est I (CPP Sud-Est I) (#2022-A01307-36) (ethics committee for France), and ErasmusMC ethics committee (#MEC-2022-0365) (ethics committee for the Netherlands). Signed informed consent will be obtained from all included patients. The findings will be published in peer-reviewed journals and presented at relevant stakeholder conferences and meetings.

TRIAL REGISTRATION

Clinical Trials.gov (NCT05271929), EudraCT (2021-006621-22).

Subcutaneous anti-COVID-19 hyperimmune immunoglobulin for prevention of disease in asymptomatic individuals with SARS-CoV-2 infection: a double-blind, placebo-controlled, randomised clinical trial

BACKGROUND

Anti-COVID-19 hyperimmune immunoglobulin (hIG) can provide standardized and controlled antibody content. Data from controlled clinical trials using hIG for the prevention or treatment of COVID-19 outpatients have not been reported. We assessed the safety and efficacy of subcutaneous anti-COVID-19 hyperimmune immunoglobulin 20% (C19-IG20%) compared to placebo in preventing development of symptomatic COVID-19 in asymptomatic individuals with SARS-CoV-2 infection.

METHODS

We did a multicentre, randomized, double-blind, placebo-controlled trial, in asymptomatic unvaccinated adults (≥18 years of age) with confirmed SARS-CoV-2 infection within 5 days between April 28 and December 27, 2021. Participants were randomly assigned (1:1:1) to receive a blinded subcutaneous infusion of 10 mL with 1 g or 2 g of C19-IG20%, or an equivalent volume of saline as placebo. The primary endpoint was the proportion of participants who remained asymptomatic through day 14 after infusion. Secondary endpoints included the proportion of individuals who required oxygen supplementation, any medically attended visit, hospitalisation, or ICU, and viral load reduction and viral clearance in nasopharyngeal swabs. Safety was assessed as the proportion of patients with adverse events. The trial was terminated early due to a lack of potential benefit in the target population in a planned interim analysis conducted in December 2021. ClinicalTrials.gov registry: NCT04847141.

FINDINGS

461 individuals (mean age 39.6 years [SD 12.8]) were randomized and received the intervention within a mean of 3.1 (SD 1.27) days from a positive SARS-CoV-2 test. In the prespecified modified intention-to-treat analysis that included only participants who received a subcutaneous infusion, the primary outcome occurred in 59.9% (91/152) of participants receiving 1 g C19-IG20%, 64.7% (99/153) receiving 2 g, and 63.5% (99/156) receiving placebo (difference in proportions 1 g C19-IG20% vs. placebo, -3.6%; 95% CI -14.6% to 7.3%, p = 0.53; 2 g C19-IG20% vs placebo, 1.1%; -9.6% to 11.9%, p = 0.85). None of the secondary clinical efficacy endpoints or virological endpoints were significantly different between study groups. Adverse event rate was similar between groups, and no severe or life-threatening adverse events related to investigational product infusion were reported.

INTERPRETATION

Our findings suggested that administration of subcutaneous human hyperimmune immunoglobulin C19-IG20% to asymptomatic individuals with SARS-CoV-2 infection was safe but did not prevent development of symptomatic COVID-19.

FUNDING

Grifols.

Effectiveness of COVID-19 Convalescent Plasma (CCP) During the Pandemic Era: A Literature Review

Worldwide pandemic with coronavirus disease-2019 (COVID-19) was caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). As November 2, 2022, World Health Organization (WHO) received 628,035,553 reported incidents on COVID-19, with 6,572,800 mortalities and, with a total 12,850,970,971 vaccine doses have been delivered as of October 31, 2022. The infection can cause mild or self-limiting symptoms of pulmonary and severe infections or death may be caused by SARS-CoV-2 infection. Simultaneously, antivirals, corticosteroids, immunological treatments, antibiotics, and anticoagulants have been proposed as potential medicines to cure COVID-19 affected patients. Among these initial treatments, COVID-19 convalescent plasma (CCP), which was retrieved from COVID-19 recovered patients to be used as passive immune therapy, in which antibodies from cured patients were given to infected patients to prevent illness. Such treatment has yielded the best results in earlier with preventative or early stages of illness. Convalescent plasma (CP) is the first treatment available when infectious disease initially appears, although few randomized controlled trials (RCTs) were conducted to evaluate its effectiveness. The historical record suggests with potential benefit for other respiratory infections, as coronaviruses like Severe Acute Respiratory Syndrome-CoV-I (SARS-CoV-I) and Middle Eastern Respiratory Syndrome (MERS), though the analysis of such research is constrained by some non-randomized experiments (NREs). Rigorous studies on CP are made more demanding by the following with the immediacy of the epidemics, CP use may restrict the ability to utilize it for clinical testing, non-homogenous nature of product, highly decentralized manufacturing process; constraints with capacity to measure biologic function, ultimate availability of substitute therapies, as antivirals, purified immune globulins, or monoclonal antibodies. Though, it is still not clear how effectively CCP works among hospitalized COVID-19 patients. The current review tries to focus on its efficiency and usage in clinical scenarios and identifying existing benefits of implementation during pandemic or how it may assist with future pandemic preventions.

Immune Plasma for the Treatment of COVID-19: Lessons Learned so far

COVID-19 convalescent plasma (CCP) has been explored as one of the treatment options for COVID-19. Results of many cohort studies and clinical trials have been recently published. At first glance, the results of the CCP studies appear to be inconsistent. However, it became clear that CCP is not beneficial if CCP with low anti-SARS-CoV-2 antibody concentrations is used, if it is administered late in advanced disease stages, and to patients who already mounted an antibody response against SARS-CoV-2 at the time of CCP transfusion. On the other hand, CCP may prevent progression to severe COVID-19 when very high-titer CCP is given early in vulnerable patients. Immune escape of new variants is a challenge for passive immunotherapy. While new variants of concern developed resistance to most clinically used monoclonal antibodies very rapidly, immune plasma from individuals immunized by both a natural SARS-CoV-2 infection and SARS-CoV-2 vaccination retained neutralizing activity against variants. This review briefly summarizes the evidence on CCP treatment to date and identifies further research needs. Ongoing research on passive immunotherapy is not only relevant for improving care for vulnerable patients in the ongoing SARS-CoV-2 pandemic, but even more as a model for passive immunotherapy in case of future pandemics with a newly evolving pathogen. Compared to other drugs, which must be newly developed in a pandemic (e.g., monoclonal antibodies, antiviral drugs), convalescent plasma is rapidly available, inexpensive to produce, and can be adaptive to viral evolution by selection of contemporary convalescent donors.

Convalescent plasma therapy for coronavirus disease 2019 in ambulatory versus hospitalized patients: Efficacy and risk of thromboembolism

Background

Although early evidence concluded a lack of clinical benefit of convalescent plasma therapy (CPT) in COVID-19 management, recent trials have demonstrated the therapeutic potential of CPT in ambulatory care. CPT may also potentiate thromboembolic events, given the presence of coagulation factors and the prothrombotic state of COVID-19.

Objectives

The present study aimed to assess and compare the clinical efficacy and the risk of venous thromboembolism (VTE)/arterial thromboembolism (ATE) of CPT in ambulatory versus hospitalized patients with COVID-19.

Methods

MEDLINE, Embase, and Cochrane CENTRAL were searched from December 2019 to December 2022 for randomized controlled trials that investigated the use of CPT against placebo or standard of care in adult patients with COVID-19. The primary outcome was nonmortality disease progression. Secondary outcomes include VTE, ATE, 28-day mortality, clinical improvement, length of hospitalization, sepsis/fever, and major adverse cardiovascular events.

Results

Twenty randomized controlled trials, with 21,340 patients, were included. CPT significantly reduced nonmortality disease progression in ambulatory patients (odds ratio [OR], 0.72; 95% CI, 0.56-0.92; P = .009) but not in hospitalized patients (OR, 1.03; 95% CI, 0.94-1.12; P = .58). The risk of VTE and ATE did not differ between the CPT and the control group (OR, 1.16; 95% CI, 0.82-1.66; P = .40; and OR, 1.01; 95% CI, 0.37-2.79; P = .98, respectively). No conclusive differences between CPT and control groups were noted in 28-day mortality, clinical improvement, length of hospitalization, risk of sepsis/fever, and major adverse cardiovascular events.

Conclusion

In conclusion, treatment of COVID-19 with CPT prevents the progression of COVID-19 in the ambulatory care. It is not associated with an increased risk of VTE, ATE, or other adverse events.

Therapeutic advances in COVID-19

Over 2 years have passed since the start of the COVID-19 pandemic, which has claimed millions of lives. Unlike the early days of the pandemic, when management decisions were based on extrapolations from in vitro data, case reports and case series, clinicians are now equipped with an armamentarium of therapies based on high-quality evidence. These treatments are spread across seven main therapeutic categories: anti-inflammatory agents, antivirals, antithrombotics, therapies for acute hypoxaemic respiratory failure, anti-SARS-CoV-2 (neutralizing) antibody therapies, modulators of the renin-angiotensin-aldosterone system and vitamins. For each of these treatments, the patient population characteristics and clinical settings in which they were studied are important considerations. Although few direct comparisons have been performed, the evidence base and magnitude of benefit for anti-inflammatory and antiviral agents clearly outweigh those of other therapeutic approaches such as vitamins. The emergence of novel variants has further complicated the interpretation of much of the available evidence, particularly for antibody therapies. Importantly, patients with acute and chronic kidney disease were under-represented in many of the COVID-19 clinical trials, and outcomes in this population might differ from those reported in the general population. Here, we examine the clinical evidence for these therapies through a kidney medicine lens.

One-year follow-up of the CAPSID randomized trial for high-dose convalescent plasma in severe COVID-19 patients

BACKGROUNDResults of many randomized trials on COVID-19 convalescent plasma (CCP) have been reported, but information on long-term outcome after CCP treatment is limited. The objectives of this extended observation of the randomized CAPSID trial are to assess long-term outcome and disease burden in patients initially treated with or without CCP.METHODSOf 105 randomized patients, 50 participated in the extended observation. Quality of life (QoL) was assessed by questionnaires and a structured interview. CCP donors (n = 113) with asymptomatic to moderate COVID-19 were included as a reference group.RESULTSThe median follow-up of patients was 396 days, and the estimated 1-year survival was 78.7% in the CCP group and 60.2% in the control (P = 0.08). The subgroup treated with a higher cumulative amount of neutralizing antibodies showed a better 1-year survival compared with the control group (91.5% versus 60.2%, P = 0.01). Medical events and QoL assessments showed a consistent trend for better results in the CCP group without reaching statistical significance. There was no difference in the increase in neutralizing antibodies after vaccination between the CCP and control groups.CONCLUSIONThe trial demonstrated a trend toward better outcome in the CCP group without reaching statistical significance. A predefined subgroup analysis showed a significantly better outcome (long-term survival, time to discharge from ICU, and time to hospital discharge) among those who received a higher amount of neutralizing antibodies compared with the control group. A substantial long-term disease burden remains after severe COVID-19.Trial registrationEudraCT 2020-001310-38 and ClinicalTrials.gov NCT04433910.FundingBundesministerium für Gesundheit (German Federal Ministry of Health).

Home and Out-of-Hospital Therapy with COVID-19 Convalescent Plasma in Europe

COVID19 convalescent plasma (CCP) has proven an effective treatment for outpatients, and CCP collected from vaccinated donors is among the few effective therapeutic options for immunocompromised patients. Despite this, most countries are still relying over in-hospital compassionate usages outside clinical trials. Given the need for early treatment, home transfusions are expecially needed. We review here the state of the art for out-of-hospital CCP transfusions and discuss solutions to potential burocratic hurdles.

Clinical Practice Guidelines From the Association for the Advancement of Blood and Biotherapies (AABB): COVID-19 Convalescent Plasma

DESCRIPTION

Coronavirus disease 2019 convalescent plasma (CCP) has emerged as a potential treatment of COVID-19. However, meta-analysis data and recommendations are limited. The Association for the Advancement of Blood and Biotherapies (AABB) developed clinical practice guidelines for the appropriate use of CCP.

METHODS

These guidelines are based on 2 living systematic reviews of randomized controlled trials (RCTs) evaluating CCP from 1 January 2019 to 26 January 2022. There were 33 RCTs assessing 21 916 participants. The results were summarized using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) method. An expert panel reviewed the data using the GRADE framework to formulate recommendations.

RECOMMENDATION 1 (OUTPATIENT)

The AABB suggests CCP transfusion in addition to the usual standard of care for outpatients with COVID-19 who are at high risk for disease progression (weak recommendation, moderate-certainty evidence).

RECOMMENDATION 2 (INPATIENT)

The AABB recommends against CCP transfusion for unselected hospitalized persons with moderate or severe disease (strong recommendation, high-certainty evidence). This recommendation does not apply to immunosuppressed patients or those who lack antibodies against SARS-CoV-2.

RECOMMENDATION 3 (INPATIENT)

The AABB suggests CCP transfusion in addition to the usual standard of care for hospitalized patients with COVID-19 who do not have SARS-CoV-2 antibodies detected at admission (weak recommendation, low-certainty evidence).

RECOMMENDATION 4 (INPATIENT)

The AABB suggests CCP transfusion in addition to the usual standard of care for hospitalized patients with COVID-19 and preexisting immunosuppression (weak recommendation, low-certainty evidence).

RECOMMENDATION 5 (PROPHYLAXIS)

The AABB suggests against prophylactic CCP transfusion for uninfected persons with close contact exposure to a person with COVID-19 (weak recommendation, low-certainty evidence).

GOOD CLINICAL PRACTICE STATEMENT

CCP is most effective when transfused with high neutralizing titers to infected patients early after symptom onset.

Multi-center matched cohort study of convalescent plasma for hospitalized patients with COVID-19

Background

Although frequently used in the early pandemic, data on the effectiveness of COVID-19 convalescent plasma (CCP) remain mixed. We investigated the effectiveness and safety of CCP in hospitalized COVID-19 patients in real-world practices during the first two waves of the pandemic in a multi-hospital healthcare system in Texas.

Methods and findings

Among 11,322 hospitalized patients with confirmed COVID-19 infection from July 1, 2020 to April 15, 2021, we included patients who received CCP and matched them with those who did not receive CCP within ±2 days of the transfusion date across sites within strata of sex, age groups, days and use of dexamethasone from hospital admission to the match date, and oxygen requirements 4–12 hours prior to the match date. Cox proportional hazards model estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for effectiveness outcomes in a propensity score 1:1 matched cohort. Pre-defined safety outcomes were described. We included 1,245 patients each in the CCP treated and untreated groups. Oxygen support was required by 93% of patients at the baseline. The pre-defined primary effectiveness outcome of 28-day in-hospital all-cause mortality (HR = 0.85; 95%CI: 0.66,1.10) were similar between treatment groups. Sensitivity and stratified analyses found similar null results. CCP-treated patients were less likely to be discharged alive (HR = 0.82; 95%CI: 0.74, 0.91), and more likely to receive mechanical ventilation (HR = 1.48; 95%CI: 1.12, 1.96). Safety outcomes were rare and similar between treatment groups.

Conclusion

The findings in this large, matched cohort of patients hospitalized with COVID-19 and mostly requiring oxygen support at the time of treatment, do not support a clinical benefit in 28-day in-hospital all-cause mortality for CCP. Future studies should assess the potential benefits with specifically high-titer units in perhaps certain subgroups of patients (e.g. those with early disease or immunocompromised).

Clinical and Virological Response to Convalescent Plasma in a Chronic Lymphocytic Leukemia Patient with COVID-19 Pneumonia

The burden of COVID-19 remains unchanged for immunocompromised patients who do not respond to vaccines. Unfortunately, Omicron sublineages are resistant to monoclonal antibodies authorized in Europe so far, and small chemical antivirals have contraindications and toxicities that have not been studied in these patients. We report here the successful treatment of COVID-19 pneumonia lasting for 4 months after the transfusion of COVID-19 convalescent plasma (CCP) in a patient with severe immunosuppression due to both chronic lymphocytic leukemia and venetoclax treatment. The patient achieved a complete clinical, radiological and virological response after six transfusions (600 mL each) of high-titer CCP collected from triple-vaccinated and convalescent donors. This dramatic case adds to the mounting evidence of CCP efficacy in immunocompromised patients, provided that high-titer and large volumes are infused.