Some Studies Suggest Intravenous Immunoglobulin Could Help Treat COVID-19
Researchers finding ways to use intravenous immunoglobulin for COVID-19 treatment.
As researchers and physicians try to identify ways to effectively treat and prevent COVID-19, the disease caused by the novel coronavirus SARS-CoV-2, some are studying whether high-dose intravenous immunoglobulin (IVIg) could work. IVIg is a common blood plasma product that is used to treat other immune disorders.
IVIg is purified from the mixed plasma of healthy people, with protein being the main component, which is abundant in bacterial antibodies and viral Immunoglobulin G (IgG). It is clinically used as an adjunctive therapy for the treatment of severe pneumonia caused by influenza, in addition to other immune disorders. There have now been several small studies of the use of IVIg in treating COVID-19.
This is different than using convalescent antibodies to treat the disease. Convalescent antibodies refer to taking the blood from people who have recovered from the disease, isolating the plasma, and using their immunoglobulins, a type of immune cell, to treat patients. IVIg is acquired from a more general healthy population, and hospitals typically already have it in stock.
“We want to help now and see what we could do with the product that is readily available,” Flemming Nielsen, president of the U.S. subsidiary of Switzerland-based Octapharma AG, told the Wall Street Journal.
Octapharma is studying whether IVIg can help COVID-19 patients and working with other companies to manufacture coronavirus-specific immunoglobulin.
It’s not known if off-the-shelf IVIg would be effective in treating COVID-19, and how it works is not well understood.
Last year, well before anyone had heard of COVID-19, there was an acute shortage of immunoglobulin in the U.S. It wasn’t a particularly new shortage at that time, either, although now, because of the pandemic, there are concerns of significant shortages.
In a January 2019 article written by John G. Boyle, president, and chief executive officer of the Immune Deficiency Foundation (IDF), he noted that manufacturing and distribution of Ig is complex. It is also considered a specialty drug, meaning it’s not usually available at the local pharmacy.
Michelle Vogel, vice president of patient advocacy for CSI Pharmacy, a specialty pharmacy, told WSJ, “We are just starting to recover from the shortage and this hit.”
Although it’s possible that IVIg will be effective, most in the field believe working with convalescent plasma makes more sense. Still, a retrospective study of 58 cases of severe or critical COVID-19 in the Wuhan Third Hospital from January to February 2020 suggested that IVIg within 48 hour of admission reduced ventilator use, reduced hospital and ICU length of stay, and ultimately improved 28-day mortality.
A broader study of electronic medical records at eight treatment centers in China suggested the benefit was much smaller. Octapharma is supporting a trial of 20 patients at Sharp HealthCare hospitals in the San Diego area. Another company, Spain-based Grifols SA, has released non-peer-reviewed data showing antibodies in its IVIg products might bind to the virus, which suggests the products could help COVID-19 patients. The company is working to get a study going in Spain. And physicians at Sainte-Anne Hospital in Paris are launching a trial of IVIG in COVID-19 patients, potentially in 140 COVID-19 patients on mechanical ventilation.
A big question, not only is effectiveness, but at what point during the disease would IVIg be effective, if at all. A study in three patients in China at the Jin Yin-tan Hospital in Wuhan seemed to suggest that IVIg works best early in the disease.
“The best timing of antivirals, if there are any, may lie on the phase before acceleration,” the researchers wrote. “When clinical deterioration begins, the first few days of deterioration may present a critical point when potent suppression of inflammatory cascade could save the patients from fatal immune-mediated injuries.”
They add, “The timing of IVIg administration is very critical in practice. Patients might not receive much benefit when overall systemic damage has already taken place.”