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LONDON, March 16 (Reuters) - Scientists are to test a newtwo-shot Ebola vaccine using an experimental shot from Britain'sGlaxoSmithKline, which is already in clinical trials inAfrica, and a new kind of booster from Emergent BioSolutions.
The Maryland-based biotech company said on Monday itsmodified vaccinia Ankara (MVA) Ebola Zaire vaccine would be usedin an initial Phase I clinical study to be conducted byresearchers at the University of Oxford.
Although Ebola case numbers have fallen to a low level, drugcompanies are still pushing ahead with efforts to develop aneffective vaccine, which may help fight the next outbreak, evenif it does not come in time for the current epidemic.
One big area of debate is whether it is better to have asingle or double-shot vaccine. Administering a follow-up boosterwould almost certainly give greater protection but it would alsomake immunisation far more complicated.
Currently, Denmark's Bavarian Nordic, which isworking with Johnson & Johnson, has the most advancedMVA booster vaccine, which has also been tested in a small trialwith GSK's shot.
However, Bavarian's booster component needs to be grown inchicken eggs, which makes production difficult, while Emergent'scell-based vaccine does away with the need for eggs. (Reporting by Ben Hirschler, editing by William Hardy)
