Abstract: Compositions and methods are provided for the administration of particulates comprising at least one bioactive agent which, in selected embodiments, may comprise and immunoactive agent. In this respect, the invention provides for both topical and systemic delivery of the bioactive agent using, for example, the respiratory, gastrointestinal or urogenital tracts. The particulates may be in the form of dry powders or combined with a non-aqueous suspension medium to provide stabilized dispersions. In preferred embodiments, the disclosed compositions will be used in conjunction with inhalation devices such as metered dose inhalers, dry powder inhalers, atomizers or nebulizers for targeted delivery of the agent to mucosal surfaces.