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Published on: August 24, 2015
Pathogen reduction with methylene blue does not have an impact on the clinical effectiveness of COVID-19 convalescent
Irene Romera Martínez1,2, José Luis Bueno Cabrera1,2, José María Domingo-Morera3
1Department of Hematology, Hospital Universitario Puerta de Hierro Majadahonda, Madrid, Spain.
Background And Objectives:
There is a concern about a possible deleterious effect of pathogen reduction (PR) with methylene blue (MB) on the function of immunoglobulins of COVID-19 convalescent plasma (CCP). We have evaluated whether MB-treated CCP is associated with a poorer clinical response compared to other inactivation systems at the ConPlas-19 clinical trial.
Materials And Methods:
This was an ad hoc sub-study of the ConPlas-19 clinical trial comparing the proportion of patients transfused with MB-treated CCP who had a worsening of respiration versus those treated with amotosalen (AM) or riboflavin (RB).
Results:
One-hundred and seventy-five inpatients with SARS-CoV-2 pneumonia were transfused with a single CCP unit. The inactivation system of the CCP units transfused was MB in 90 patients (51.4%), RB in 60 (34.3%) and AM in 25 (14.3%). Five out of 90 patients (5.6%) transfused with MB-treated CCP had worsening respiration compared to 9 out of 85 patients (10.6%) treated with alternative PR methods (p = 0.220). Of note, MB showed a trend towards a lower rate of respiratory progressions at 28 days (risk ratio, 0.52; 95% confidence interval, 0.18-1.50).
Conclusion:
Our data suggest that MB-treated CCP does not provide a worse clinical outcome compared to the other PR methods for the treatment of COVID-19.
Insights
Methylene blue (MB) pathogen reduction (PR) treatment of COVID-19 convalescent plasma (CCP) did not worsen patient respiratory outcomes compared to alternative PR methods. MB-treated CCP showed a trend towards improved respiratory progression in SARS-CoV-2 pneumonia patients.
Area of Science:
- Immunology
- Infectious Diseases
- Plasma Therapeutics
Background:
- Concerns exist regarding the impact of methylene blue (MB) pathogen reduction (PR) on immunoglobulin function in COVID-19 convalescent plasma (CCP).
- Evaluating the clinical efficacy of MB-treated CCP is crucial for patient safety and treatment protocols.
Purpose of the Study:
- To assess if MB-treated CCP is associated with poorer clinical outcomes compared to other inactivation systems.
- To compare respiratory worsening in patients receiving MB-treated CCP versus amotosalen (AM) or riboflavin (RB) treated CCP.
Main Methods:
- An ad hoc sub-study of the ConPlas-19 clinical trial was conducted.
- Compared the proportion of patients experiencing respiratory worsening after transfusion with MB-treated CCP versus alternative PR methods (AM or RB).
Main Results:
- 175 SARS-CoV-2 pneumonia patients received a single CCP unit.
- 5.6% of patients receiving MB-treated CCP (n=90) had respiratory worsening versus 10.6% receiving alternative PR methods (n=85).
- MB treatment showed a trend towards a lower rate of respiratory progression at 28 days (RR 0.52).
Conclusions:
- MB-treated CCP did not result in worse clinical outcomes compared to other PR methods.
- MB treatment appears safe and potentially beneficial for COVID-19 treatment with CCP.
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