Summary of COVID-19 convalescent plasma studies
Studies
Meta Analysis
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Early terminated RCT 44 hospitalized COVID-19 patients showing no significant differences with convalescent plasma treatment.
Feb 2024, Acta Medica Philippina, https://actamedicaphilippina.upm.edu.ph/index.php/acta/article/view/4903, https://c19p.org/gauiran
Small RCT with 28 early and 30 deferred (treated according to prespecified deterioration criteria) convalescent plasma patients, not showing significant differences. "Early" is relative, with a median of 5 days from symptom onset. 13 patients in the deferred group received plasma.
Mar 2021, PLOS Medicine, https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1003415, https://c19p.org/balcells
RCT 147 patients in Denmark, showing no significant difference in outcomes with convalescent plasma. The trial was terminated due to futility.
Sep 2022, Scientific Reports, https://www.nature.com/articles/s41598-022-19629-z, https://c19p.org/thorlaciusussing
RCT 34 hospitalized patients in the USA, showing no significant difference with convalescent plasma treatment.
Aug 2021, NCT04421404, https://clinicaltrials.gov/ct2/show/results/NCT04421404, https://c19p.org/hsue
129 patient convalescent plasma late treatment RCT: 52% higher mortality (p=0.37).
RCT 129 severe COVID-19 patients in Brazil, showing no significant difference in outcomes with convalescent plasma.
Jun 2022, The Lancet Regional Health - Americas, https://www.sciencedirect.com/science/article/pii/S2667193X22000333, https://c19p.org/song4
RCT 160 hospitalized patients in Brazil, showing no significant difference in outcomes with convalescent plasma.
Jul 2021, European Respiratory J., http://erj.ersjournals.com/lookup/doi/10.1183/13993003.01471-2021, https://c19p.org/sekine
RCT 29 severe COVID-19 patients showing no significant differences with convalescent plasma compared to fresh frozen plasma.
Oct 2020, Anais da Academia Brasileira de Ciências, https://www.scielo.br/j/aabc/a/sFk4vCTR69vjG9wTsKHxLwC/?lang=en#, https://c19p.org/bajpai
RCT 511 emergency department patients, 257 assigned to convalescent plasma, showing no significant difference in outcomes.
Aug 2021, NEJM, https://www.nejm.org/doi/full/10.1056/NEJMoa2103784, https://c19p.org/korley
120 patient convalescent plasma late treatment RCT: 25% higher mortality (p=0.54), 10% higher combined mortality/intubation (p=0.76), and 6% slower viral clearance (p=0.76).
RCT 180 hospitalized COVID-19 patients with respiratory impairment in Italy showing no significant improvement in mortality or mechanical ventilation with either standard plasma or COVID-19 convalescent plasma compared to standard of care.
Nov 2022, BMC Infectious Diseases, https://bmcinfectdis.biomedcentral.com/articles/10.1186/s12879-022-07716-5, https://c19p.org/manzini
RCT 400 hospitalized severe COVID-19 patients in India showing no significant difference in time to clinical improvement, mortality, or other outcomes with convalescent plasma compared to standard treatment. In a subgroup analysis, results were better for patients receiving plasma within 3 days of admission. There was no difference in outcomes based on patient baseline antibody levels.
Apr 2022, BMJ Open, https://bmjopen.bmj.com/lookup/doi/10.1136/bmjopen-2021-055189, https://c19p.org/bajpai2
RCT 72 outpatients in the USA showing no significant difference with convalescent plasma treatment.
Aug 2021, NCT04438057, https://clinicaltrials.gov/study/NCT04438057, https://c19p.org/vanhise
RCT 12 patients in Italy, showing no significant difference with convalescent plasma treatment. Results are from [Axfors].
May 2021, NCT04374526, https://clinicaltrials.gov/study/NCT04374526, https://c19p.org/teofili
RCT 1,070 outpatients in the USA, showing no significant difference in recovery with convalescent plasma treatment. Long COVID results are from [Gebo]
Jan 2023, The J. Infectious Diseases, https://academic.oup.com/jid/advance-article/doi/10.1093/infdis/jiad023/7017764, https://c19p.org/baksh
960 patient convalescent plasma late treatment RCT: 3% higher mortality (p=0.86) and 4% worse 7-point scale results (p=0.76).
RCT 947 hospitalized patients in the USA, showing no signficant difference with convalescent plasma treatment.
Nov 2022, Chest, https://www.sciencedirect.com/science/article/pii/S0012369222012016, https://c19p.org/self4
RCT 940 hospitalized patients, 614 assigned to convalescent plasma, showing no significant differences.
Sep 2021, Nature Medicine, https://www.nature.com/articles/s41591-021-01488-2, https://c19p.org/begin
RCT 120 hospitalized patients in Iran, showing no significant differences with convalescent plasma treatment.
Dec 2021, Tanaffos 21:1, https://europepmc.org/article/med/36258918, https://c19p.org/jalili
Retrospective 430 hospitalized COVID-19 patients with type 2 diabetes in Poland showing lower mortality with metformin and higher mortality with remdesivir, convalescent plasma, and aspirin in univariable analysis. These results were not statistically significant except for aspirin, and no baseline information per treatment is provided to assess confounding.
Mar 2024, Biomedicines, https://www.mdpi.com/2227-9059/12/3/605, https://c19p.org/lewandowski2cp
Case control study with 2,431 hospitalized COVID-19 patients in India, showing higher mortality with convalescent plasma treatment, without statistical significance.
Apr 2023, The American J. Tropical Medicine and Hygiene, https://www.ajtmh.org/view/journals/tpmd/108/4/article-p727.xml, https://c19p.org/krishnan2cp
22 patient convalescent plasma late treatment RCT: 17% higher mortality (p=1).
RCT 22 hospitalized patients, show no significant difference in mortality with convalescent plasma. Results are from [Axfors].
Nov 2021, PACTR202006760881890, https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=12168, https://c19p.org/abayomi2
RCT 91 hospitalized patients in Colombia showing shorter time to discharge with convalescent plasma, but higher mortality (without statistical significance).
Jun 2022, BMC Infectious Diseases, https://bmcinfectdis.biomedcentral.com/articles/10.1186/s12879-022-07560-7, https://c19p.org/rojas
RCT 136 hospitalized COVID-19 patients in Uganda, showing no significant benefit with convalescent plasma treatment.
Aug 2021, BMJ Open Respiratory Research, https://bmjopenrespres.bmj.com/lookup/doi/10.1136/bmjresp-2021-001017, https://c19p.org/kirenga3
PSM retrospective 29 hospitals in Saudi Arabia, showing longer ICU and hospitalization time with convalescent plasma, but no significant difference in mortality.
Feb 2023, Saudi Pharmaceutical J., https://www.sciencedirect.com/science/article/pii/S1319016423000348, https://c19p.org/alshamranicp
Prospective study of 65 hospitalized COVID-19 patients in the Philippines treated with convalescent plasma and 65 matched controls showing no significant difference in mortality and longer hospitalization with treatment.
Feb 2022, medRxiv, https://www.medrxiv.org/content/10.1101/2022.02.23.22271424, https://c19p.org/mesina
RCT 57 hospitalized COVID-19 patients showing no significant difference in outcomes with convalescent plasma treatment.
Mar 2024, Infectious Diseases, https://www.tandfonline.com/doi/full/10.1080/23744235.2024.2329957, https://c19p.org/khawaja
Retrospective propensity-matched analysis of 290 hospitalized COVID-19 patients who received convalescent plasma (CCP) compared to 290 controls, showing no significant difference in 30-day mortality, ECMO/mechanical ventilation, or hospital length of stay.
Oct 2024, PLOS ONE, https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0309449, https://c19p.org/iasella
Retrospective 144 immunocompromised patients treated with anti-CD20 therapy prior to contracting COVID-19. Among 50 patients hospitalized within 14 days, administration of high-titer convalescent plasma in the first 14 days was not associated with improved outcomes.
Nov 2023, Scientific Reports, https://www.nature.com/articles/s41598-023-48145-x, https://c19p.org/kasten
5,044 patient convalescent plasma late treatment study: 4% higher mortality (p=0.88).
Target trial emulation with 4,755 patients showing no significant difference in 30-day mortality with convalescent plasma.
Jun 2021, The J. Infectious Diseases, https://academic.oup.com/jid/article/224/6/967/6307367, https://c19p.org/cho2
RCT 464 hospitalized patients in India, 235 treated with convalescent plasma, showing no improvement in combined death at 28 days or progression to severe disease.
Oct 2020, BMJ, https://www.bmj.com/content/371/bmj.m3939, https://c19p.org/agarwal
RCT 190 hospitalized severe condition patients in Mexico, showing no significant difference between convalescent plasma and human immunoglobulin treatment.
Mar 2021, medRxiv, https://www.medrxiv.org/content/10.1101/2021.03.28.21254507, https://c19p.org/gonzalez
RCT 16,287 hospitalized patients in the UK, showing no significant differences with convalescent plasma treatment. Subgroup analysis shows better results for those treated <= 7 days from symptom onset.
Jan 2021, Recovery Collaborative Group, The Lancet, https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00897-7/fulltext, https://c19p.org/recoverycp
RCT 489 hospitalized COVID-19 patients in Belgium, showing no significant difference in outcomes with convalescent plasma.
Aug 2021, European Respiratory J., http://erj.ersjournals.com/lookup/doi/10.1183/13993003.01724-2021, https://c19p.org/devos
RCT 120 hospitalized patients in France, showing no significant difference in outcomes with convalescent plasma treatment, with the exception of lower mortality in the subgroup of immunosuppressed patients.
Aug 2022, medRxiv, https://www.medrxiv.org/content/10.1101/2022.08.09.22278329, https://c19p.org/lacombe
RCT 134 hospitalized patients showing no significant difference in outcomes with convalescent plasma for all patients, however significantly improved mortality and time to improvement was seen for patients with cancer.
Dec 2022, Nature Cancer, https://www.nature.com/articles/s43018-022-00503-w, https://c19p.org/denkinger
Long-term followup for the REMAP-CAP very late stage ICU trial, showing no significant difference with convalescent plasma treatment.
Dec 2022, JAMA, https://jamanetwork.com/journals/jama/fullarticle/2799870, https://c19p.org/higginscp
RCT 416 outpatients in the Netherlands, showing no significant difference with convalesent plasma treatment. Hospitalization was lower, and improved results were seen with ≤5 days of symptoms, without statistical significance.
Aug 2022, Clinical Microbiology and Infection, https://www.sciencedirect.com/science/article/pii/S1198743X22004219, https://c19p.org/gharbharan2
RCT 941 hospitalized patients in the USA, showing no significant difference with convalescent plasma treatment. PASC results are from [Yoon]
Dec 2021, JAMA Internal Medicine, https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2787090, https://c19p.org/ortigoza
RCT 110 hospitalized patients in Brazil, showing no significant difference in outcomes with high-dose convalescent plasma.
Mar 2022, Emerging Infectious Diseases, https://wwwnc.cdc.gov/eid/article/28/3/21-2299_article.htm, https://c19p.org/desantis
RCT 158 patients in Ecuador, showing no significant difference in mortality with convalescent plasma. Authors note indications of improved results for earlier treatment.
Jan 2022, Transfusion Medicine, https://onlinelibrary.wiley.com/doi/10.1111/tme.12851, https://c19p.org/baldeon
RCT 86 hospitalized patients, 43 treated with convalescent plasma, showing no significant differences with treatment. Authors conclude that the most likely explanation was already high antibody titers on the day of inclusion, and they recommend treating patients early.
May 2021, Nature Communications, https://www.nature.com/articles/s41467-021-23469-2, https://c19p.org/gharbharan
RCT 62 hospitalized patients in Iran, showing no significant difference in mortality and length of stay with convalescent plasma.
Apr 2021, Internal and Emergency Medicine, https://link.springer.com/10.1007/s11739-021-02734-8, https://c19p.org/pouladzadeh
RCT 333 hospitalized patients in Argentina, 228 treated with convalescent plasma, showing no significant differences in clinical status or mortality.
Nov 2020, NEJM, https://www.nejm.org/doi/full/10.1056/nejmoa2031304, https://c19p.org/simonovich
RCT 74 hospitalized patients in the USA, showing no significant difference with convalescent plasma treatment.
Apr 2021, Critical Care Medicine, https://journals.lww.com/10.1097/CCM.0000000000005066, https://c19p.org/bennettguerrero
RCT 487 patients in Italy, showing no significant difference in outcomes with convalescent plasma.
Nov 2021, JAMA Network Open, https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2786680, https://c19p.org/menichetti
RCT 188 convalescent plasma and 188 control patients, showing no significant difference in outcomes.
Feb 2022, The Lancet Respiratory Medicine, https://www.sciencedirect.com/science/article/pii/S2213260021005452, https://c19p.org/alemany
RCT 80 severe COVID-19 patients in India showing no significant difference in 30-day mortality with convalescent plasma therapy (CPT). Patients receiving CPT had greater reduction in inflammatory cytokines, but this did not translate to clinical benefit in terms of survival or duration of hospital stay.
Nov 2020, Nature Communications, https://www.nature.com/articles/s41467-022-28064-7, https://c19p.org/ray
RCT 105 hospitalized patients in Germany, 53 treated with convalescent plasma, showing no significant difference in mortality or the primary composite outcome of survival and no longer fulfilling criteria for severe COVID-19 on day 21.
Oct 2021, J. Clinical Investigation, https://www.jci.org/articles/view/152264, https://c19p.org/korper
RCT 103 hospitalized patients in South Africa, showing no significant difference in outcomes with convalescent plasma.
Feb 2022, Scientific Reports, https://www.nature.com/articles/s41598-022-06221-8https://www.nature.com/articles/s41598-022-06221-8.pdf, https://c19p.org/vandenberg
RCT 31 hospitalized patients requiring supplemental oxygen in Sweden, showing no significant difference in outcomes with convalescent plasma.
Dec 2021, BMC Research Notes, https://bmcresnotes.biomedcentral.com/articles/10.1186/s13104-021-05847-7, https://c19p.org/holm
Small RCT with 40 hospitalized patients in Bahrain, 20 treated with convalescent plasma, not showing significant differences.
Nov 2020, Scientific Reports, https://www.nature.com/articles/s41598-021-89444-5, https://c19p.org/alqahtani
103 patient convalescent plasma late treatment RCT: 35% lower mortality (p=0.3), 15% greater improvement (p=0.37), and 76% improved viral clearance (p=0.01).
Small RCT 103 severe condition patients, 52 treated with convalescent plasma, showing improved viral clearance but no statistically significant improvements in mortality or clinical improvement. ChiCTR2000029757.
Jun 2020, JAMA, https://jamanetwork.com/journals/jama/fullarticle/2766943, https://c19p.org/li8
Early terminated RCT with 81 hospitalized patients, 38 treated with convalescent plasma, showing lower progression with treatment.
Sep 2020, medRxiv, https://www.medrxiv.org/content/10.1101/2020.08.26.20182444v3, https://c19p.org/avendanosola
RCT 1,181 outpatients in the USA, mean 6 days from symptom onset, showing lower hospitalization with treatment. NCT04373460.
Dec 2021, New England J. Medicine, https://www.nejm.org/doi/10.1056/NEJMoa2119657, https://c19p.org/sullivan
RCT 160 patients >=65 with symptom onset <72 hours, 80 treated with convalescent plasma, showing lower progression to severe disease with treatment.
Jan 2021, NEJM, https://www.nejm.org/doi/10.1056/NEJMoa2033700, https://c19p.org/libster
RCT 79 hospitalized patients in the USA, showing significant benefit in clinical severity score and 28-day mortality with convalescent plasma treatment.
Dec 2021, J. Clinical Investigation, https://www.jci.org/articles/view/155114, https://c19p.org/bar
1. Gauiran et al., Convalescent Plasma as Adjunctive Therapy for Hospitalized Patients with COVID-19: The Co-CLARITY Trial
44 patient convalescent plasma late treatment RCT: 400% higher mortality (p=0.49), 100% higher ICU admission (p=1), and 7% longer hospitalization (p=0.7).Early terminated RCT 44 hospitalized COVID-19 patients showing no significant differences with convalescent plasma treatment.
Feb 2024, Acta Medica Philippina, https://actamedicaphilippina.upm.edu.ph/index.php/acta/article/view/4903, https://c19p.org/gauiran
2. Balcells et al., Early versus deferred anti-SARS-CoV-2 convalescent plasma in patients admitted for COVID-19: A randomized phase II clinical trial
58 patient convalescent plasma early treatment RCT: 247% higher mortality (p=0.17), 163% higher ventilation (p=0.22), and 23% higher progression (p=0.51).Small RCT with 28 early and 30 deferred (treated according to prespecified deterioration criteria) convalescent plasma patients, not showing significant differences. "Early" is relative, with a median of 5 days from symptom onset. 13 patients in the deferred group received plasma.
Mar 2021, PLOS Medicine, https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1003415, https://c19p.org/balcells
3. Thorlacius-Ussing et al., A randomized placebo-controlled trial of convalescent plasma for adults hospitalized with COVID-19 pneumonia
144 patient convalescent plasma late treatment RCT: 76% higher mortality (p=0.43), 31% higher ICU admission (p=0.77), and 41% worse 7-point scale results (p=0.32).RCT 147 patients in Denmark, showing no significant difference in outcomes with convalescent plasma. The trial was terminated due to futility.
Sep 2022, Scientific Reports, https://www.nature.com/articles/s41598-022-19629-z, https://c19p.org/thorlaciusussing
4. Hsue et al., Effects of COVID-19 Convalescent Plasma (CCP) on Coronavirus-associated Complications in Hospitalized Patients (CAPRI)
34 patient convalescent plasma late treatment RCT: 425% higher ventilation (p=0.21) and 425% higher progression (p=0.21).RCT 34 hospitalized patients in the USA, showing no significant difference with convalescent plasma treatment.
Aug 2021, NCT04421404, https://clinicaltrials.gov/ct2/show/results/NCT04421404, https://c19p.org/hsue
129 patient convalescent plasma late treatment RCT: 52% higher mortality (p=0.37).
RCT 129 severe COVID-19 patients in Brazil, showing no significant difference in outcomes with convalescent plasma.
Jun 2022, The Lancet Regional Health - Americas, https://www.sciencedirect.com/science/article/pii/S2667193X22000333, https://c19p.org/song4
6. Sekine et al., Convalescent plasma for COVID-19 in hospitalised patients: an open-label, randomised clinical trial
160 patient convalescent plasma late treatment RCT: 38% higher mortality (p=0.42), 11% worse improvement (p=0.74), and 67% longer hospitalization (p=0.87).RCT 160 hospitalized patients in Brazil, showing no significant difference in outcomes with convalescent plasma.
Jul 2021, European Respiratory J., http://erj.ersjournals.com/lookup/doi/10.1183/13993003.01471-2021, https://c19p.org/sekine
7. Bajpai et al., Comparison of safety and efficacy of convalescent plasma with fresh frozen plasma in severe covid-19 patients
29 patient convalescent plasma late treatment RCT: 323% higher mortality (p=0.22), 221% higher ventilation (p=0.33), 25% shorter hospitalization (p=0.08), and 33% improved viral clearance (p=0.11).RCT 29 severe COVID-19 patients showing no significant differences with convalescent plasma compared to fresh frozen plasma.
Oct 2020, Anais da Academia Brasileira de Ciências, https://www.scielo.br/j/aabc/a/sFk4vCTR69vjG9wTsKHxLwC/?lang=en#, https://c19p.org/bajpai
8. Korley et al., Early Convalescent Plasma for High-Risk Outpatients with Covid-19
511 patient convalescent plasma early treatment RCT: 396% higher mortality (p=0.22), 10% lower hospitalization (p=0.59), and 6% lower progression (p=0.7).RCT 511 emergency department patients, 257 assigned to convalescent plasma, showing no significant difference in outcomes.
Aug 2021, NEJM, https://www.nejm.org/doi/full/10.1056/NEJMoa2103784, https://c19p.org/korley
120 patient convalescent plasma late treatment RCT: 25% higher mortality (p=0.54), 10% higher combined mortality/intubation (p=0.76), and 6% slower viral clearance (p=0.76).
RCT 180 hospitalized COVID-19 patients with respiratory impairment in Italy showing no significant improvement in mortality or mechanical ventilation with either standard plasma or COVID-19 convalescent plasma compared to standard of care.
Nov 2022, BMC Infectious Diseases, https://bmcinfectdis.biomedcentral.com/articles/10.1186/s12879-022-07716-5, https://c19p.org/manzini
10. Bajpai et al., Efficacy of convalescent plasma therapy in the patient with COVID-19: a randomised control trial (COPLA-II trial)
400 patient convalescent plasma late treatment RCT: 14% higher mortality (p=0.62), 13% higher ventilation (p=0.76), 2% longer ICU admission (p=0.8), and no change in hospitalization (p=0.98).RCT 400 hospitalized severe COVID-19 patients in India showing no significant difference in time to clinical improvement, mortality, or other outcomes with convalescent plasma compared to standard treatment. In a subgroup analysis, results were better for patients receiving plasma within 3 days of admission. There was no difference in outcomes based on patient baseline antibody levels.
Apr 2022, BMJ Open, https://bmjopen.bmj.com/lookup/doi/10.1136/bmjopen-2021-055189, https://c19p.org/bajpai2
11. Van Hise et al., Evaluating the Efficacy of Convalescent Plasma in Symptomatic Outpatients Infected With COVID-19
103 patient convalescent plasma early treatment RCT: 441% higher hospitalization (p=0.55).RCT 72 outpatients in the USA showing no significant difference with convalescent plasma treatment.
Aug 2021, NCT04438057, https://clinicaltrials.gov/study/NCT04438057, https://c19p.org/vanhise
12. Teofili et al., Early transfusIon of COVID-19 Convalescent Plasma in Elderly COVID-19 Patients to Prevent Disease Progression
29 patient convalescent plasma late treatment RCT: 100% higher mortality (p=1).RCT 12 patients in Italy, showing no significant difference with convalescent plasma treatment. Results are from [Axfors].
May 2021, NCT04374526, https://clinicaltrials.gov/study/NCT04374526, https://c19p.org/teofili
13. Baksh et al., Symptom duration and resolution with early outpatient treatment of convalescent plasma for COVID- 19: a randomized trial
1,070 patient convalescent plasma late treatment RCT: 1% worse recovery (p=0.62) and 4% higher PASC (p=0.78).RCT 1,070 outpatients in the USA, showing no significant difference in recovery with convalescent plasma treatment. Long COVID results are from [Gebo]
Jan 2023, The J. Infectious Diseases, https://academic.oup.com/jid/advance-article/doi/10.1093/infdis/jiad023/7017764, https://c19p.org/baksh
960 patient convalescent plasma late treatment RCT: 3% higher mortality (p=0.86) and 4% worse 7-point scale results (p=0.76).
RCT 947 hospitalized patients in the USA, showing no signficant difference with convalescent plasma treatment.
Nov 2022, Chest, https://www.sciencedirect.com/science/article/pii/S0012369222012016, https://c19p.org/self4
15. Bégin et al., Convalescent plasma for hospitalized patients with COVID-19: an open-label, randomized controlled trial
938 patient convalescent plasma late treatment RCT: 13% higher mortality (p=0.33) and 16% higher combined mortality/intubation (p=0.18).RCT 940 hospitalized patients, 614 assigned to convalescent plasma, showing no significant differences.
Sep 2021, Nature Medicine, https://www.nature.com/articles/s41591-021-01488-2, https://c19p.org/begin
16. Jalili et al., Effect of Convalescent Plasma Therapy on Clinical Improvement of COVID-19 Patients: A Randomized Clinical Trial
120 patient convalescent plasma late treatment RCT: 45% higher mortality (p=0.38), 8% higher ICU admission (p=0.85), 250% higher ARDS (p=0.16), and 10% longer hospitalization (p=0.39).RCT 120 hospitalized patients in Iran, showing no significant differences with convalescent plasma treatment.
Dec 2021, Tanaffos 21:1, https://europepmc.org/article/med/36258918, https://c19p.org/jalili
17. Lewandowski et al., Insulin and Metformin Administration: Unravelling the Multifaceted Association with Mortality across Various Clinical Settings Considering Type 2 Diabetes Mellitus and COVID-19
430 patient convalescent plasma late treatment study: 62% higher mortality (p=0.12).Retrospective 430 hospitalized COVID-19 patients with type 2 diabetes in Poland showing lower mortality with metformin and higher mortality with remdesivir, convalescent plasma, and aspirin in univariable analysis. These results were not statistically significant except for aspirin, and no baseline information per treatment is provided to assess confounding.
Mar 2024, Biomedicines, https://www.mdpi.com/2227-9059/12/3/605, https://c19p.org/lewandowski2cp
18. Krishnan et al., Predictors of Mortality among Patients Hospitalized with COVID-19 during the First Wave in India: A Multisite Case-Control Study
convalescent plasma late treatment study: 270% higher mortality (p=0.07).Case control study with 2,431 hospitalized COVID-19 patients in India, showing higher mortality with convalescent plasma treatment, without statistical significance.
Apr 2023, The American J. Tropical Medicine and Hygiene, https://www.ajtmh.org/view/journals/tpmd/108/4/article-p727.xml, https://c19p.org/krishnan2cp
22 patient convalescent plasma late treatment RCT: 17% higher mortality (p=1).
RCT 22 hospitalized patients, show no significant difference in mortality with convalescent plasma. Results are from [Axfors].
Nov 2021, PACTR202006760881890, https://pactr.samrc.ac.za/TrialDisplay.aspx?TrialID=12168, https://c19p.org/abayomi2
20. Rojas et al., Safety and efficacy of convalescent plasma for severe COVID-19: a randomized, single blinded, parallel, controlled clinical study
91 patient convalescent plasma late treatment RCT: 220% higher mortality (p=0.16), 38% higher hospital discharge (p=0.04), and 25% worse viral clearance (p=0.72).RCT 91 hospitalized patients in Colombia showing shorter time to discharge with convalescent plasma, but higher mortality (without statistical significance).
Jun 2022, BMC Infectious Diseases, https://bmcinfectdis.biomedcentral.com/articles/10.1186/s12879-022-07560-7, https://c19p.org/rojas
21. Kirenga et al., Efficacy of convalescent plasma for treatment of COVID-19 in Uganda
136 patient convalescent plasma late treatment RCT: 21% higher mortality (p=0.8), 9% lower progression (p=1), no change in recovery (p=0.77), and 50% slower viral clearance (p=0.2).RCT 136 hospitalized COVID-19 patients in Uganda, showing no significant benefit with convalescent plasma treatment.
Aug 2021, BMJ Open Respiratory Research, https://bmjopenrespres.bmj.com/lookup/doi/10.1136/bmjresp-2021-001017, https://c19p.org/kirenga3
22. Alshamrani et al., Comprehensive evaluation of six interventions for hospitalized patients with COVID-19: A propensity score matching study
246 patient convalescent plasma late treatment PSM study: 14% higher mortality (p=0.39), 17% higher progression (p=0.05), 43% longer ICU admission (p=0.003), and 32% longer hospitalization (p=0.01).PSM retrospective 29 hospitals in Saudi Arabia, showing longer ICU and hospitalization time with convalescent plasma, but no significant difference in mortality.
Feb 2023, Saudi Pharmaceutical J., https://www.sciencedirect.com/science/article/pii/S1319016423000348, https://c19p.org/alshamranicp
23. Mesina et al., Use of Convalescent Plasma Therapy with Best Available Treatment (BAT) among Hospitalized COVID-19 Patients: A Multi-Center Study
130 patient convalescent plasma late treatment study: 29% higher mortality (p=0.54) and 60% longer hospitalization (p=0.07).Prospective study of 65 hospitalized COVID-19 patients in the Philippines treated with convalescent plasma and 65 matched controls showing no significant difference in mortality and longer hospitalization with treatment.
Feb 2022, medRxiv, https://www.medrxiv.org/content/10.1101/2022.02.23.22271424, https://c19p.org/mesina
24. Khawaja et al., Double-blinded, randomised, placebo-controlled trial of convalescent plasma for COVID-19: analyses by neutralising antibodies homologous to donors’ variants
57 patient convalescent plasma late treatment RCT: 73% lower ventilation (p=0.28).RCT 57 hospitalized COVID-19 patients showing no significant difference in outcomes with convalescent plasma treatment.
Mar 2024, Infectious Diseases, https://www.tandfonline.com/doi/full/10.1080/23744235.2024.2329957, https://c19p.org/khawaja
25. Iasella et al., Impact of variable titer COVID-19 convalescent plasma and recipient SARS-CoV2-specific humoral immunity on survival in hospitalized patients
580 patient convalescent plasma late treatment PSM study: 26% higher mortality (p=0.14), 1% higher ventilation (p=1), and no change in progression (p=1).Retrospective propensity-matched analysis of 290 hospitalized COVID-19 patients who received convalescent plasma (CCP) compared to 290 controls, showing no significant difference in 30-day mortality, ECMO/mechanical ventilation, or hospital length of stay.
Oct 2024, PLOS ONE, https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0309449, https://c19p.org/iasella
26. Kasten et al., COVID-19 outcome is not affected by anti-CD20 or high-titer convalescent plasma in immunosuppressed patients
50 patient convalescent plasma late treatment study: 4% higher mortality (p=1).Retrospective 144 immunocompromised patients treated with anti-CD20 therapy prior to contracting COVID-19. Among 50 patients hospitalized within 14 days, administration of high-titer convalescent plasma in the first 14 days was not associated with improved outcomes.
Nov 2023, Scientific Reports, https://www.nature.com/articles/s41598-023-48145-x, https://c19p.org/kasten
5,044 patient convalescent plasma late treatment study: 4% higher mortality (p=0.88).
Target trial emulation with 4,755 patients showing no significant difference in 30-day mortality with convalescent plasma.
Jun 2021, The J. Infectious Diseases, https://academic.oup.com/jid/article/224/6/967/6307367, https://c19p.org/cho2
28. Agarwal et al., Convalescent plasma in the management of moderate covid-19 in adults in India: open label phase II multicentre randomised controlled trial (PLACID Trial)
464 patient convalescent plasma late treatment RCT: 7% higher mortality (p=0.74), 7% higher progression (p=0.74), 1% lower ventilation (p=0.98), and 28% improved viral clearance (p=0.02).RCT 464 hospitalized patients in India, 235 treated with convalescent plasma, showing no improvement in combined death at 28 days or progression to severe disease.
Oct 2020, BMJ, https://www.bmj.com/content/371/bmj.m3939, https://c19p.org/agarwal
29. Gonzalez et al., Efficacy and safety of convalescent plasma and intravenous immunoglobulin in critically ill COVID-19 patients. A controlled clinical trial
190 patient convalescent plasma late treatment study: 7% higher mortality (p=0.76).RCT 190 hospitalized severe condition patients in Mexico, showing no significant difference between convalescent plasma and human immunoglobulin treatment.
Mar 2021, medRxiv, https://www.medrxiv.org/content/10.1101/2021.03.28.21254507, https://c19p.org/gonzalez
30. Recovery Collaborative Group et al., Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial
11,558 patient convalescent plasma late treatment RCT: no change in mortality (p=0.95) and 1% lower hospital discharge (p=0.57).RCT 16,287 hospitalized patients in the UK, showing no significant differences with convalescent plasma treatment. Subgroup analysis shows better results for those treated <= 7 days from symptom onset.
Jan 2021, Recovery Collaborative Group, The Lancet, https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00897-7/fulltext, https://c19p.org/recoverycp
31. Devos et al., Early high antibody titre convalescent plasma for hospitalised COVID-19 patients: DAWn-plasma
483 patient convalescent plasma late treatment RCT: 1% lower mortality (p=0.98), 8% higher ventilation (p=0.78), and no change in ICU admission (p=1).RCT 489 hospitalized COVID-19 patients in Belgium, showing no significant difference in outcomes with convalescent plasma.
Aug 2021, European Respiratory J., http://erj.ersjournals.com/lookup/doi/10.1183/13993003.01724-2021, https://c19p.org/devos
32. Lacombe et al., COVID-19 convalescent plasma to treat hospitalised COVID-19 patients with or without underlying immunodeficiency
120 patient convalescent plasma late treatment RCT: 49% lower mortality (p=0.16), 68% higher progression (p=0.18), and 7% longer hospitalization (p=0.99).RCT 120 hospitalized patients in France, showing no significant difference in outcomes with convalescent plasma treatment, with the exception of lower mortality in the subgroup of immunosuppressed patients.
Aug 2022, medRxiv, https://www.medrxiv.org/content/10.1101/2022.08.09.22278329, https://c19p.org/lacombe
33. Denkinger et al., Anti-SARS-CoV-2 antibody-containing plasma improves outcome in patients with hematologic or solid cancer and severe COVID-19: a randomized clinical trial
134 patient convalescent plasma late treatment RCT: 8% lower mortality (p=0.39), 2% higher ventilation (p=1), and 22% improved 7-point scale results (p=0.22).RCT 134 hospitalized patients showing no significant difference in outcomes with convalescent plasma for all patients, however significantly improved mortality and time to improvement was seen for patients with cancer.
Dec 2022, Nature Cancer, https://www.nature.com/articles/s43018-022-00503-w, https://c19p.org/denkinger
34. Higgins et al., Long-term (180-Day) Outcomes in Critically Ill Patients With COVID-19 in the REMAP-CAP Randomized Clinical Trial
1,734 patient convalescent plasma ICU RCT: 1% lower mortality (p=0.9).Long-term followup for the REMAP-CAP very late stage ICU trial, showing no significant difference with convalescent plasma treatment.
Dec 2022, JAMA, https://jamanetwork.com/journals/jama/fullarticle/2799870, https://c19p.org/higginscp
35. Gharbharan et al., Outpatient convalescent plasma therapy for high-risk patients with early COVID-19. A randomized placebo-controlled trial
416 patient convalescent plasma early treatment RCT: 14% lower progression (p=0.42), 39% lower hospitalization (p=0.22), and 1% worse recovery (p=0.92).RCT 416 outpatients in the Netherlands, showing no significant difference with convalesent plasma treatment. Hospitalization was lower, and improved results were seen with ≤5 days of symptoms, without statistical significance.
Aug 2022, Clinical Microbiology and Infection, https://www.sciencedirect.com/science/article/pii/S1198743X22004219, https://c19p.org/gharbharan2
36. Ortigoza et al., Efficacy and Safety of COVID-19 Convalescent Plasma in Hospitalized Patients
941 patient convalescent plasma late treatment RCT: 12% lower mortality (p=0.45), 8% improved 7-point scale results (p=0.5), and 2% higher PASC (p=0.88).RCT 941 hospitalized patients in the USA, showing no significant difference with convalescent plasma treatment. PASC results are from [Yoon]
Dec 2021, JAMA Internal Medicine, https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2787090, https://c19p.org/ortigoza
37. De Santis et al., High-Dose Convalescent Plasma for Treatment of Severe COVID-19
107 patient convalescent plasma late treatment RCT: 13% lower mortality (p=0.67).RCT 110 hospitalized patients in Brazil, showing no significant difference in outcomes with high-dose convalescent plasma.
Mar 2022, Emerging Infectious Diseases, https://wwwnc.cdc.gov/eid/article/28/3/21-2299_article.htm, https://c19p.org/desantis
38. Baldeón et al., Effect of convalescent plasma as complementary treatment in patients with moderate COVID-19 infection
158 patient convalescent plasma late treatment RCT: 12% lower mortality (p=1).RCT 158 patients in Ecuador, showing no significant difference in mortality with convalescent plasma. Authors note indications of improved results for earlier treatment.
Jan 2022, Transfusion Medicine, https://onlinelibrary.wiley.com/doi/10.1111/tme.12851, https://c19p.org/baldeon
39. Gharbharan et al., Effects of potent neutralizing antibodies from convalescent plasma in patients hospitalized for severe SARS-CoV-2 infection
86 patient convalescent plasma late treatment RCT: 4% lower mortality (p=0.95) and 12% higher hospital discharge (p=0.68).RCT 86 hospitalized patients, 43 treated with convalescent plasma, showing no significant differences with treatment. Authors conclude that the most likely explanation was already high antibody titers on the day of inclusion, and they recommend treating patients early.
May 2021, Nature Communications, https://www.nature.com/articles/s41467-021-23469-2, https://c19p.org/gharbharan
40. Pouladzadeh et al., A randomized clinical trial evaluating the immunomodulatory effect of convalescent plasma on COVID-19-related cytokine storm
60 patient convalescent plasma late treatment RCT: 30% longer hospitalization (p=0.06).RCT 62 hospitalized patients in Iran, showing no significant difference in mortality and length of stay with convalescent plasma.
Apr 2021, Internal and Emergency Medicine, https://link.springer.com/10.1007/s11739-021-02734-8, https://c19p.org/pouladzadeh
41. Simonovich et al., A Randomized Trial of Convalescent Plasma in Covid-19 Severe Pneumonia
333 patient convalescent plasma late treatment RCT: 4% lower mortality (p=1) and 19% improved 7-point scale results (p=0.4).RCT 333 hospitalized patients in Argentina, 228 treated with convalescent plasma, showing no significant differences in clinical status or mortality.
Nov 2020, NEJM, https://www.nejm.org/doi/full/10.1056/nejmoa2031304, https://c19p.org/simonovich
42. Bennett-Guerrero et al., Severe Acute Respiratory Syndrome Coronavirus 2 Convalescent Plasma Versus Standard Plasma in Coronavirus Disease 2019 Infected Hospitalized Patients in New York
74 patient convalescent plasma late treatment RCT: 19% lower mortality (p=0.75) and no change in improvement (p=1).RCT 74 hospitalized patients in the USA, showing no significant difference with convalescent plasma treatment.
Apr 2021, Critical Care Medicine, https://journals.lww.com/10.1097/CCM.0000000000005066, https://c19p.org/bennettguerrero
43. Menichetti et al., Effect of High-Titer Convalescent Plasma on Progression to Severe Respiratory Failure or Death in Hospitalized Patients With COVID-19 Pneumonia
471 patient convalescent plasma late treatment RCT: 23% lower mortality (p=0.47), 4% higher ventilation (p=1), and 12% lower progression (p=0.54).RCT 487 patients in Italy, showing no significant difference in outcomes with convalescent plasma.
Nov 2021, JAMA Network Open, https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2786680, https://c19p.org/menichetti
44. Alemany et al., High-titre methylene blue-treated convalescent plasma as an early treatment for outpatients with COVID-19: a randomised, placebo-controlled trial
376 patient convalescent plasma early treatment RCT: 80% lower mortality (p=0.5), 5% higher hospitalization (p=1), 5% worse recovery (p=0.67), and 4% worse viral clearance (p=0.33).RCT 188 convalescent plasma and 188 control patients, showing no significant difference in outcomes.
Feb 2022, The Lancet Respiratory Medicine, https://www.sciencedirect.com/science/article/pii/S2213260021005452, https://c19p.org/alemany
45. Ray et al., A phase 2 single center open label randomised control trial for convalescent plasma therapy in patients with severe COVID-19
80 patient convalescent plasma late treatment RCT: 33% lower mortality (p=0.34).RCT 80 severe COVID-19 patients in India showing no significant difference in 30-day mortality with convalescent plasma therapy (CPT). Patients receiving CPT had greater reduction in inflammatory cytokines, but this did not translate to clinical benefit in terms of survival or duration of hospital stay.
Nov 2020, Nature Communications, https://www.nature.com/articles/s41467-022-28064-7, https://c19p.org/ray
46. Körper et al., Results of the CAPSID randomized trial for high-dose convalescent plasma in patients with severe COVID-19
105 patient convalescent plasma late treatment RCT: 37% lower mortality (p=0.19) and 16% improved recovery (p=0.32).RCT 105 hospitalized patients in Germany, 53 treated with convalescent plasma, showing no significant difference in mortality or the primary composite outcome of survival and no longer fulfilling criteria for severe COVID-19 on day 21.
Oct 2021, J. Clinical Investigation, https://www.jci.org/articles/view/152264, https://c19p.org/korper
47. van den Berg et al., Convalescent plasma in the treatment of moderate to severe COVID-19 pneumonia: a randomized controlled trial (PROTECT-Patient Trial)
103 patient convalescent plasma late treatment RCT: 17% lower mortality (p=0.65), 67% lower ventilation (p=0.36), 5% greater improvement (p=1), and 3% lower hospital discharge (p=1).RCT 103 hospitalized patients in South Africa, showing no significant difference in outcomes with convalescent plasma.
Feb 2022, Scientific Reports, https://www.nature.com/articles/s41598-022-06221-8https://www.nature.com/articles/s41598-022-06221-8.pdf, https://c19p.org/vandenberg
48. Holm et al., Convalescence plasma treatment of COVID-19: results from a prematurely terminated randomized controlled open-label study in Southern Sweden
31 patient convalescent plasma late treatment RCT: 19% lower progression (p=1), 57% higher need for oxygen therapy (p=0.43), and 62% longer hospitalization (p=0.21).RCT 31 hospitalized patients requiring supplemental oxygen in Sweden, showing no significant difference in outcomes with convalescent plasma.
Dec 2021, BMC Research Notes, https://bmcresnotes.biomedcentral.com/articles/10.1186/s13104-021-05847-7, https://c19p.org/holm
49. AlQahtani et al., Randomized controlled trial of convalescent plasma therapy against standard therapy in patients with severe COVID-19 disease
40 patient convalescent plasma late treatment RCT: 33% lower ventilation (p=0.47) and 22% shorter hospitalization (p=0.12).Small RCT with 40 hospitalized patients in Bahrain, 20 treated with convalescent plasma, not showing significant differences.
Nov 2020, Scientific Reports, https://www.nature.com/articles/s41598-021-89444-5, https://c19p.org/alqahtani
103 patient convalescent plasma late treatment RCT: 35% lower mortality (p=0.3), 15% greater improvement (p=0.37), and 76% improved viral clearance (p=0.01).
Small RCT 103 severe condition patients, 52 treated with convalescent plasma, showing improved viral clearance but no statistically significant improvements in mortality or clinical improvement. ChiCTR2000029757.
Jun 2020, JAMA, https://jamanetwork.com/journals/jama/fullarticle/2766943, https://c19p.org/li8
51. Avendaño-Solà et al., Convalescent Plasma for COVID-19: A multicenter, randomized clinical trial
81 patient convalescent plasma late treatment RCT: 88% lower mortality (p=0.12) and 93% lower progression (p=0.01).Early terminated RCT with 81 hospitalized patients, 38 treated with convalescent plasma, showing lower progression with treatment.
Sep 2020, medRxiv, https://www.medrxiv.org/content/10.1101/2020.08.26.20182444v3, https://c19p.org/avendanosola
52. Sullivan et al., Early Outpatient Treatment for Covid-19 with Convalescent Plasma
1,181 patient convalescent plasma late treatment RCT: 86% lower mortality (p=0.12) and 54% lower hospitalization (p=0.005).RCT 1,181 outpatients in the USA, mean 6 days from symptom onset, showing lower hospitalization with treatment. NCT04373460.
Dec 2021, New England J. Medicine, https://www.nejm.org/doi/10.1056/NEJMoa2119657, https://c19p.org/sullivan
53. Libster et al., Early High-Titer Plasma Therapy to Prevent Severe Covid-19 in Older Adults
160 patient convalescent plasma early treatment RCT: 67% lower ICU admission (p=0.17) and 48% lower progression (p=0.03).RCT 160 patients >=65 with symptom onset <72 hours, 80 treated with convalescent plasma, showing lower progression to severe disease with treatment.
Jan 2021, NEJM, https://www.nejm.org/doi/10.1056/NEJMoa2033700, https://c19p.org/libster
54. Bar et al., A randomized controlled study of convalescent plasma for individuals hospitalized with COVID-19 pneumonia
79 patient convalescent plasma late treatment RCT: 81% lower mortality (p=0.03), 44% greater improvement (p=0.18), and 51% lower ventilation (p=0.16).RCT 79 hospitalized patients in the USA, showing significant benefit in clinical severity score and 28-day mortality with convalescent plasma treatment.
Dec 2021, J. Clinical Investigation, https://www.jci.org/articles/view/155114, https://c19p.org/bar
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