Emergent’s candidate - modified vaccinia Ankara (MVA) Ebola Zaire vaccine (MVA EBOZ) – is being testing with GSK’s developmental chimp Adenovirus type 3 (ChAd3) Ebola vaccine in Phase I trials taking place at the Jenner Institute in the UK.
MVA EBOZ supplies were produced using ProBioGen’s AGE1.CR.pIX virus platform, which uses cells from the Muscovy duck rather than fertilised hens’ eggs. The approach has many advantages for drugmakers according to a spokesman for the German firm.
“One main advantage of shifting away from embryonated eggs is that the overall logistics and continuous dependence on a primary material becomes obsolete. Our cell bank has been characterized ahead of producing the vaccines.
“Because timing is critical, material from embryonated eggs can be tested against adventitious agents only in the final vaccine bulk. This increases risks for the final bulk” he said.
Downstream processing
Harvesting the MVA produced by the duck cells is also more straightforward according to ProBioGen, whose spokesman told us “downstream processing is different for vaccines derived from eggs or a continuous cell line.”
He added that: “Generally one can say that, dependent on the scale and the product cell culture based processes can be much cheaper than egg based processes.”
The other advantage of using cell lines for vaccine production is that such manufacturing is not impacted by the availability of hens’ eggs, which is currently limited in the US as a result of avian influenza.
MVA EBOZ entered a Phase I study last month, the aim of which was to see it can boost response to GSK’s candidate. Maryland, US-based Emergent licensed non-exclusive rights to ProBioGen’s tech and produced its vaccine at its site in Baltimore.