Strengths and limitations of the model virus concept.
New plasma- or cell culture-based pharmaceutical manufacturing processes must be validated for their ability to eliminate potentially contaminating pathogens. To evaluate the virus elimination potential of such a process, current guidelines propose the use of model viruses. This approach is discussed based on two examples. These examples show the strengths of this approach but also its limitations. The blood processing industry was recently challenged by the emergence of a West Nile Virus (WNV) epidemic in the United States. The susceptibility of WNV and a frequently used model virus to commonly used inactivation methods is compared. Current data show a good correlation. Due to its physico-chemical properties and the high viremic titers, B19 virus (B19V), a small (diameter 18-26 nm), robust, non-enveloped parvovirus, is a considerable challenge for the plasma processing industry. Mice minute virus (MMV), an animal parvovirus, is used as a model for B19V. Data show that B19V is considerably more susceptible to some physico-chemical inactivation methods than MMV. The examples of WNV and B19V show that the model virus concept is a practicable tool to evaluate the safety of plasma- or cell culture-derived pharmaceuticals regarding known and emerging viruses. It also underlines the need for investigational studies of relevant viruses if they can be handled in a normal virology laboratory, under moderate biosafety conditions.
Käsermann
F
F
Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland.
Kempf
C
C
Boschetti
N
N
D001702:Biopharmaceutics / Q000379:methods*; D001769:Blood / Q000821:virology*; D006801:Humans; D007700:Kinetics; D008954:Models, Biological; D016732:Parvovirus B19, Human / Q000737:chemistry / Q000302:isolation & purification / Q000472:pathogenicity; D014902:West Nile virus / Q000737:chemistry / Q000302:isolation & purification / Q000472:pathogenicity