Administration of immunoglobulins may improve the clinical course of people suffering from severe COVID-19

After almost 200 million people having passed COVID-19 worldwide, the functioning of this disease is still a great unknown. Even so, one thing that the scientific community associates with severe symptomatology of this disease is an excessive inflammatory response. Now, a study led by IrsiCaixa has shown that high-dose intravenous immunoglobulins administration (IVIG) may be useful as a treatment for COVID-19 in people with severe symptomatology, thanks to its ability to fight inflammation.

Although we currently have vaccines that can effectively prevent severe disease caused by SARS-CoV-2, we still have a long way to go in developing drugs and therapies to help alleviate the severe symptoms of COVID-19. "One of the strategies we are studying is the intravenous administration of a high dose of immunoglobulins, which are antibodies obtained from people who have not necessarily been infected by SARS-CoV-2", says Mª Luisa Rodríguez de la Concepción, postdoctoral researcher at IrsiCaixa and co-author of the study.

Inflammation markers

Researchers involved in the study analysed a total of 41 inflammation-related markers from plasma samples obtained from 5 hospitalized COVID-19 patients treated with IVIG. These markers were analysed just before the start of treatment, and on days 3, 7 and 14 post-treatment. "What we have been able to observe is that some of the markers analyzed decreased during the two weeks after the start of treatment. Therefore, we can say that the administration of IVIG in these patients can improve their clinical evolution thanks to the fact that it fights the excessive inflammatory response developed by the patient", explains Erola Ainsua Enrich, postdoctoral researcher at IrsiCaixa and co-author of the study. Specifically, the study shows that molecules such as cytokines, among other factors that determine a high state of inflammation, are reduced after treatment.

Avoiding disease severity

The excessive inflammation that occurs in severe cases of COVID-19 is related, in part, to an uncontrolled response by the immune system in trying to fight the virus. This response may be responsible for the damage to some organs, such as the lungs, in the most severe patients. "The administration of IVIG was well tolerated by the patients in the study and improved their recovery process, reducing the levels of inflammation", describes Jorge Carrillo, principal investigator at IrsiCaixa and co-leader of the study. "These results represent a proof of concept and open the way for new clinical studies with more patients to corroborate the results. In fact, a global clinical trial is currently underway to study the possibility of using these immunoglobulins in the most severe cases for which we currently have no specific treatment", he concludes.