Abstract: This invention generally relates to immunogenic compositions that comprise an HIV RNA component and a HIV polypeptide component. Immunogenic compositions that deliver antigenic epitopes in two different forms—a first epitope from human immunodeficiency virus (HIV), in RNA-coded form; and a second epitope from HIV, in polypeptide form—are effective in inducing immune response to HIV. The invention also relates to a kit comprising an HIV RNA-based priming composition and an HIV polypeptide-based boosting composition. The kit may be used for sequential administration of the priming and the boosting compositions.