Plant-based vaccines are recombinant protein subunit vaccines. The challenges facing plant-based vaccine development include technical, regulatory and economic aspects and public perception. In the technical challenges it is very difficult to select a plant system where it grows under optimized conditions to minimize the environmental risks. Ideally, the plant species choice used to produce the selected antigen should applicable for oral drug delivery in an edible vaccine form. To date, the most advanced human vaccine projects have successfully completed phase I clinical trials, & animal vaccine projects have given promising data in early phase trials targeting the specific animal species.