Reuters schreef:
"We are working on an hexavalent vaccine but for competitive reasons we are not mentioning what the sixth antigen will be," Crucell spokeswoman Oya Yavuz said.
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Despite Crucell's reluctance to reveal what antigen it will acquire, the World Health Organisation said polio is likely to be added in future to the pentavalent paediatric vaccines bought by UNICEF, forming an hexavalent vaccine.
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The NVI -- one of four groups that produce injectible polio vaccines including Sanofi-Aventis, GlaxoSmithKline (GSK.L) and the smaller Statens Serum Institute in Denmark...