The use of cell therapy in patients with Covid-19 reduced the risk of death from the disease by 60%.
Conclusion, published in the journal Inside the border Immunology , is from a review study conducted by researchers at the University of São Paulo (USP) in collaboration with German and North American scientists. The article summarizes data from 195 clinical trials conducted in 30 countries between January 2020 and December 2021.
In recent years, so-called advanced cell therapies have gained the upper hand in the fight against various diseases, especially cancer.
Basically, the techniques consist of replacing whole cells in the patient's body to regenerate or change certain sets of cells. Another strategy is to modulate the function of a population of diseased cells by injecting new cells (or cell products).
These various techniques may use the patient's own (autologous) or donor (allogeneic) stem cells (or their derivatives) that are cultured or transformed outside the body before administration.
According to the study, the most commonly used cell types in Covid-19 clinical trials were multipotent stromal or mesenchymal stem cells (derived from connective tissue), natural killer cells (derived from lymphoblasts) and mononuclear cells (derived from blood). . ), accounting for 72%, 9% and 6% of the studies, respectively.
“Cell therapy has advanced greatly in recent years and has been used to treat cancer, autoimmune, heart and infectious diseases. During the pandemic, they were used to treat Covid-19 in several clinical trials. Our work is the first to collect all these data scattered around the world and with the help of a meta-analysis ( (a statistical method that allows the pooling of data from several independent studies) to test the effectiveness of these therapies in the fight against the new disease as well as the health problems caused by Covid-19,” says Otávio Cabrals-Marques, professor and research coordinator at USP's Faculty of Medicine.
The researcher recalls that since the beginning of the pandemic, stem cell therapy and organoid models derived from stem cells have received wide attention as a new method of treating and researching Covid-19.
This is because stem cells, especially mesenchymal stem cells, have shown remarkable power in immune regulation and tissue damage repair functions.
For example, in the case of the lungs, clinical trials show, to a lesser or greater degree, that advanced cell therapies can limit the severe inflammatory response in patients infected with SARS-CoV-2, reducing lung damage. Thus, these therapies are expected to improve lung function, which, for example, will have a positive effect on fibrosis.
Despite the attention this type of approach has gained, Cabral-Marques believes it is important to reinforce the real protective effects of vaccination.
“Although research results suggest that advanced cell therapies may become an important adjuvant for patients affected by Covid-19, in the near future disease prevention through vaccination will remain the best defense”, the warning.
Data standardization
Trials of advanced cell therapy for Covid-19 were conducted in 30 countries, with an emphasis on the US, China, Iran and Spain. However, these were very heterogeneous studies, not only with very different numbers of participants, but also with different designs and methodologies.
Thus, to perform the meta-analysis, the research team collected the data to be analyzed in the Cell Trials Data Database and included information about national data, as well as excluded information such as false positives and double counting.
The authors note that there were also differences related to study phases. Many countries, especially in Europe, have strict regulations on human cell therapy that limit the number of cell therapy products. Thus, 56% of the studies did not even reach a phase 2 clinical trial involving patients with the disease, which aims to establish short-term safety, dose-response and efficacy of the product. Another limiting factor was the fact that 31% of the analyzed clinical trials did not have a control group.
“To get this figure for reducing the risk of death, it was necessary to take into account the results and characteristics of different studies, as well as make some corrections and estimates,” explains PhD student Igor Salerno Filgueiras, co-author of the study. review article.
“There are techniques to standardize this data, remove biases, and gain an unbiased perspective. This allows for conclusions that are often overlooked in a given study, but when reinforced by other analyses, provide an interesting scientific perspective,” Denny says. Leandro M Fonseca, PhD student at FAPESP, who is part of the team.
The article also highlights that studies using mesenchymal cells have had extremely heterogeneous methods of production and clinical delivery.
“The results highlight the important role that cell therapy products can play as adjuvant therapy in the management of Covid-19 and related complications. However, we still need to control key manufacturing parameters of these products to ensure comparability of the studies,” says. Cabral-Marques.
Research Systematic review and meta-analysis of cell therapy for Covid-19: global clinical trial landscape, published safety/efficacy results, cellular product manufacturing and clinical delivery can be read at: www.frontiersin.org/articles/10.3389/fimmu.2023.1200180/full.
– 17.08.2023. — Equilíbrio e Saúde