A Phase Ia study to assess the safety and immunogenicity of new malaria vaccine candidates ChAd63 CS administered alone and with MVA CS de réir De Barra, E, Hodgson, S, Ewer, K, Bliss, C, Hennigan, K, Collins, A, Berrie, E, Lawrie, A, Gilbert, S, Nicosia, A, McConkey, S, Hill, A