Safety, immunogenicity and efficacy of modified vaccinia Ankara (MVA) against Dryvax® challenge in vaccinia-naive and vaccinia-immune individuals

Modified vaccinia Ankara (MVA) was evaluated as an alternative to Dryvax (R) in vaccinia-naive and vaccinia-immune adult volunteers. Subjects received intramuscular MVA or placebo followed by Dryvax (R) challenge at 3 months. Two or more doses of MVA prior to Dryvax (R) reduced severity of lesion formation, decreased magnitude and duration of viral shedding, and augmented post-Dryvax (R) vaccinia-specific CD8+ T cell responses and extracellular enveloped virus protein-specific antibody responses. MVA vaccination is safe and immunogenic and improves the safety and immunogenicity of subsequent Dryvax (R) vaccination supporting the potential for using MVA as a vaccine in the general population to improve immunity to orthopox viruses. Published by Elsevier Ltd.