The U.S. Food and Drug Administration will allow an unapproved blood-transfusion system to be made available in an effort to increase the availability of plasma from Ebola survivors to treat newly infected patients.
California-based Cerus Corp. said the FDA has approved a request submitted in October to make its Intercept Blood System for plasma available for use under the agency's investigational device exemption.
Investigational device exemptions allow for an unapproved device to be used in a clinical study for the purpose of collecting data on its effectiveness and safety.
Under the exemption, the company said it will conduct a trial of its device in collaboration with researchers from Emory University Hospital in Atlanta, the University of Nebraska Medical Center in Omaha, the American Red Cross and America's Blood Centers. Approved for use in Europe for eight years, Intercept selectively inactivates pathogens that could potentially contaminate donated blood.
Emory will use the blood system at its facility, according to the company, in order to collect plasma from recovered Ebola patients for storage. The goal of the project will be to create a national network of collection sites for plasma that could be used to treat new Ebola cases.
“Having a supply of convalescent plasma that has been through pathogen inactivation is critical to making this therapy readily available as new Ebola patients are diagnosed and urgently require treatment,” said Dr. Anne Winkler, principal investigator for the clinical study and assistant professor of pathology and laboratory medicine at Emory, in a statement.
Ebola survivors' blood plasma has been used to treat those who are sick since the 1970s. The process, known as convalescent therapy, uses blood that has developed antibodies against the virus to help slow down the spread of the infection in order to give the patient's own immune system time to build up its own defenses.
Though evidence to support the use of such treatment has been limited, demand for blood plasma therapy has increased in light of the Ebola outbreak. In September the World Health Organization issued guidance (PDF) for health professionals on how to screen, collect, handle and store blood for convalescent therapy.
Last week the Bill and Melinda Gates Foundation announced it would donate $5.7 million to fund the study of convalescent plasma with the use of Intercept in West Africa.
In spite of the demand, it is largely unknown what role, if any, convalescent therapy plays toward the recovery of an Ebola patient. Convalescent plasma has been given to nine of the 10 Ebola patients treated in the U.S. Of those who received transfusions, all but one recovered.
Experts have questioned the feasibility of creating Ebola plasma stockpiles for use in the U.S. because there are only a few patients who could donate and they would need at least about two weeks between donations.
Researchers are hopeful that efforts to conduct convalescent therapy in West Africa may help to slow the spread of the disease that has infected more than 15,000 and killed more than 5,400 since March.
Cerus Chief Medical Officer Dr. Laurence Corash said in a news release that the Intercept “pathogen inactivation process can diminish the risk of other pathogens that may contaminate the plasma of valuable Ebola convalescent donors and will provide a new therapeutic resource for patients with Ebola.” The company did not respond to calls seeking comment.
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