Last month, the U.S. Food and Drug Administration (FDA) published a new set of guidelines for manufacturers of plasma-derived products. The recommendations are for performing nucleic acid testing (NAT) for human parvovirus B19 as an “in-process” test for the plasma used in manufacturing plasma-derived products. Such testing, according to the FDA, will identify and help to prevent the use of plasma units containing high levels of parvovirus B19.
Parvovirus B19 is a small, nonenveloped, single-stranded DNA virus. In animal studies it has been shown to be resistant to common inactivation methods. Its small size makes it is difficult to remove by filtration methods. It can be transmitted by certain blood components and plasma derivatives. However, disease transmission of the virus by transfusion is rare.
The parvovirus B19 virus causes “fifth disease,” a mild illness with a characteristic rash on the cheeks, which spread to the trunk, arms and legs. Some patients experience joint pain and swelling, which can last for several weeks. People who are immunocompromised by cancer, HIV, leukemia or who have had an organ transplant can develop chronic anemia after exposure to parvovirus B19.
The FDA noted that guidance documents such as these recommendations do not denote legally enforceable responsibilities. The guidelines state the following: “Instead, guidances describe the FDA’s current thinking on a topic and should be viewed only as recommendations, unless specific regulatory or statutory requirements are cited. The use of the word should in FDA’s guidances means that something is suggested or recommended, but not required.”
Read: “Guidance for Industry: Nucleic Acid Testing (NAT) to Reduce the Possible Risk of Parvovirus B19 Transmission by Plasma-Derived Products.”