First pathogen-reduction system for plasma approved by FDA

The Intercept Blood System for plasma--Courtesy of Cerus

Small cap Cerus ($CERS) gained more than 10% in early trading on Dec. 17 after the FDA approved its Intercept Blood System for plasma. This is the first pathogen-reduction system approved by the regulator to prepare plasma to reduce the risk of transfusion-transmitted infections.

Blood donation agencies, like the American Red Cross, typically rely on screening processes to determine if their blood products are safe. This device would allow plasma collected through apheresis, a process that separates red blood cells from plasma and returns the former to the donor, to be treated to reduce any potential pathogens including HIV, hepatitis B and hep C viruses and West Nile virus.

"The approval of devices like the Intercept Blood System allows blood establishments to prepare plasma that carries a lower risk of transmitting infectious pathogens through transfusion," Dr. Karen Midthun, director of the FDA's Center for Biologics Evaluation and Research, said in a statement from the agency.

According to the company, the Intercept system inactivates a broad spectrum of enveloped viruses, nonenveloped viruses, Gram-positive and Gram-negative bacteria, spirochetes and parasites.

"Plasma transfusions are an essential therapeutic treatment for many patients," Dr. Susan Stramer, VP of scientific affairs and biomedical services for the American Red Cross, said in a statement. "Pathogens for which there are no available screening tests continue to emerge or reemerge in the population due to increases in travel, immigration and climate change, thus potentially increasing risk of transmission to patients and impacting donor availability. Pathogen reduction adds an additional layer of safety for our plasma supply."

The company said it is awaiting FDA review of a similar system to prepare platelets; a decision could come before year end or during the first quarter, the company said on a conference call. Cerus expects to give its 2015 revenue guidance in late February on its fourth-quarter earnings call.

Cerus CEO William Greenman

"It's early to provide information on how quickly we'll see the first U.S. customers adopt the product. Blood centers need to complete the number of regulatory steps to go from initial evaluation of the product, through validations and into routine distribution to their hospital customers. We've worked closely with a number of blood centers during the clinical development program and have established strong collaborative relationships," Cerus President and CEO William Greenman said on a conference call. He added that there are more than 60 potential blood center customers in the U.S.

The system is based on a photochemical process involving a controlled exposure to ultraviolet light and amotosalen, a chemical that facilitates the inactivation process. The plasma is then purified to remove the chemical and its byproducts. There are some viral and bacterial pathogens that have been shown to be resistant to the Intercept process, such as human parvovirus B19 and spores formed by certain bacteria, the FDA said.

The Intercept system works by activating, binding to and blocking the replication of DNA and RNA, thereby preventing nucleic acid replication and rendering a pathogen inactive. Platelets, plasma and red blood cells do not require functional DNA or RNA to be effective.

It was tested in 8 clinical trials involving a total of 704 patients, the agency noted. These patients included those with acquired clotting disorders associated with liver disease and thrombotic thrombocytopenic purpura, a rare disorder of the blood coagulation system that can cause blood clots to form in small blood vessels throughout the body.

Approved in Europe for more than 10 years, the system has also been made available by the FDA for two studies: one on reducing the risk of transfusion-transmitted dengue and chikungunya viruses and the other to prepare plasma from Ebola survivors for transfusion to actively infected patients. Treated plasma from Ebola patients will be used to create a U.S. stockpile for future patients, the company said.

- here are the releases from Cerus and the FDA