A Biologics License Application (BLA) for the Procleix West Nile Virus (WNV) Assay for blood screening has been submitted to the US FDA, Gen-Probe Incorporated and Chiron Corporation jointly announced here.

"Gen-Probe's submission of the BLA for the Procleix West Nile Virus Assay ahead of schedule is another important milestone in our efforts to help safeguard the US blood supply with the most sensitive nucleic acid testing technologies," said Henry L. Nordhoff, Gen-Probe's chairman, president and chief executive officer.

"Using the Procleix West Nile Virus Assay, our customers are making an important contribution to blood safety, especially those that serve areas where there is a high incidence of mosquitoes carrying the virus," Gene Walther, acting president of Chiron Blood Testing said adding, "Regulatory submission of the West Nile Virus Assay fulfils one of the five Blood Testing goals Chiron has established for 2005."

Since July of 2003, US blood centres have used the Procleix WNV Assay to screen more than 19 million units of donated blood under an Investigational New Drug (IND) application. This testing has intercepted approximately 1,200 WNV-infected units, thereby preventing transfusion of contaminated blood into as many as 3,600 people. This investigational testing is expected to continue during the regulatory review process.

Procleix Assays and Systems incorporate state-of-the-art NAT technology to detect viral RNA and DNA in donated blood and plasma during the very early stages of infection, when those infectious agents are present but cannot be detected by immunodiagnostic tests.

WNV is a mosquito-borne virus associated with a human form of the disease ranging from mild, flu-like symptoms to severe neurological disease.