The final phase of the clinical trial of convalescent plasma treatment, a randomized controlled study in which 91 patients with COVID-19 were evaluated, showed that those who received it had a significantly earlier hospital discharge and required, on average, 3 days less of hospitalization when compared with those who only received conventional therapy.
This is one of the conclusions of the final results of this study by the PC-COVID-19 group, made up of researchers from the Universidad del Rosario, the District Institute of Science, Biotechnology and Innovation in Health (IDCBIS), the CES University, the Clínica del Occidente, the Mayor Méderi University Hospital, the CES Clinic, the University Foundation for Health Sciences (FUCS), and Services and Advice on Infectology (SAI). This project was financed by the Universidad del Rosario, Grupo ISA, IDCBIS and Suramericana.
The clinical trial included 46 patients who received convalescent plasma and conventional therapy; and 45 who only received conventional therapy. Excellent plasma tolerability was observed in the former.
Rubén Manrique, Doctor in Epidemiology and Director of Research and Innovation at CES University, said that patients who received convalescent plasma had, on average, 3 days less hospitalization compared to those who received conventional therapy. However, in patients with convalescent plasma, no greater reduction in mortality was observed compared to those who received conventional therapy.
In order to increase the sample size and obtain more evidence-based results, a prospective meta-analysis of 27 published and unpublished randomized clinical trials was performed, which included 2437 patients, all hospitalized.
It was observed that in the group that received convalescent plasma, fewer patients died (151/1304; 11.6%) than in the group that did not receive it (214/1133; 18.9%); with a combined risk ratio of 0.68 (95% CI: 0.51-0.91). That is to say,mortality could be reduced by one in three patients who receive convalescent plasma, said Dr. Juan-Manuel Anaya, director of the Center for the Study of Autoimmune Diseases (CREA) at the Universidad del Rosario.
Immunological effects in patients with severe disease
In the laboratories of CREA, IDCBIS, GenomaCES and in collaboration with the Universidad de los Andes and the Universidad de Antioquia, the composition of convalescent plasma and its effect in patients with severe disease was investigated. The results showed a significant difference between convalescent people and those with severe and active disease.
Convalescent plasma induces an early but transient effect on SARS-CoV-2 antibodies in patients with severe disease. At 28 days it was observed that convalescent plasma reduced the profile of inflammatory proteins (called cytokines).
Additionally, convalescent plasma increased memory immune cells at 28 days. Together, these results indicate that convalescent plasma has immunomodulatory properties that explain its therapeutic effect, said the director of CREA at the Universidad del Rosario.
Finally, the presence of latent autoimmunity was observed, that is, the presence of autoantibodies that would indicate autoimmune disease, as well as anti-IFN-α antibodies (an anti-viral defense cytokine) in patients with COVID-19, the meaning of which will be discussed. as well as its impact on Post-COVID-19.