Removal and inactivation of enveloped and non-enveloped viruses during the purification of a high-purity factor IX by metal chelate affinity chromatography.

Virus reduction during the copper chelate affinity chromatography stage used during the purification of a new high-purity factor IX (BPLs 9MC) has been investigated. Virus reduction for the enveloped virus Sindbis was 6.5 log, a value which included approximately 2 log of inactivation due to the use of an acidic wash buffer (pH 4.4) during chromatography. In the case of the non-enveloped hepatitis-A-like poliovirus, which is acid-resistant, the virus reduction value was 4.0 log and was exclusively due to physical virus removal during the chromatographic process.