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Efficacy of convalescent plasma therapy for COVID-19 in Japan: An open-label, randomized, controlled trial
Sho Saito1, Satoshi Kutsuna2, Imamura Akifumi3
1Disease Control and Prevention Center, National Center for Global Health and Medicine, Tokyo, Japan.
Insights
Early convalescent plasma therapy for COVID-19 did not reduce viral load in high-risk patients. This study found no significant difference in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral load reduction compared to standard care alone.
Area of Science:
- Virology
- Immunology
- Infectious Diseases
Background:
- Convalescent plasma is a potential treatment for COVID-19.
- Limited data exists on its efficacy against SARS-CoV-2.
Purpose of the Study:
- To evaluate the efficacy of high-neutralizing activity convalescent plasma in reducing SARS-CoV-2 viral load in high-risk patients.
Main Methods:
- Multicenter, open-label, randomized controlled trial.
- 25 high-risk patients received convalescent plasma or standard care within 5 days of symptom onset.
- Primary endpoint: time-weighted average change in nasopharyngeal SARS-CoV-2 viral load (days 0-5).
Main Results:
- No significant difference in viral load reduction between convalescent plasma and standard care groups (P=0.94).
- Median time from symptom onset to plasma administration was 4.5 days.
- No deaths were reported in either group.
Conclusions:
- Early administration of high-neutralizing activity convalescent plasma did not decrease viral load within five days compared to standard care.
- Further research may be needed to determine optimal timing or patient selection for convalescent plasma therapy.
Background:
Convalescent plasma is a potential therapeutic option for patients with coronavirus disease 2019 (COVID-19). Despite its use for treating several viral infections, we lack comprehensive data on its efficacy against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
Methods:
We conducted a multicenter, open-label, randomized controlled trial of convalescent plasma therapy with high neutralizing activity against SARS-CoV-2 in high-risk patients within five days after the onset of COVID-19 symptoms. The primary endpoint was the time-weighted average change in the SARS-CoV-2 viral load in nasopharyngeal swabs from days 0-5.
Results:
Between February 24, 2021, and November 30, 2021, 25 patients were randomly assigned to either convalescent plasma (n = 14) or standard of care (n = 11) groups. Four patients discontinued their allocated convalescent plasma, and 21 were included in the modified intention-to-treat analysis. The median interval between the symptom onset and plasma administration was 4.5 days (interquartile range, 3-5 days). The primary outcome of the time-weighted average change in the SARS-CoV-2 viral load in nasopharyngeal swabs did not significantly differ between days 0-5 (1.2 log10 copies/mL in the convalescent plasma vs. 1.2 log10 copies/mL in the standard of care (effect estimate, 0.0 [95% confidence interval, -0.8-0.7]; P = 0.94)). No deaths were observed in either group.
Conclusions:
The early administration of convalescent plasma with high neutralizing activity did not contribute to a decrease in the viral load within five days compared with the standard of care alone.
