Abstract: The present invention provides novel compositions for transdermal delivery of at least one immunogen to an individual, which compositions comprise (a) said at least one immunogen (b) an occlusion vehicle and (c) an immunogen delivery system in the form of a PosIntro or a cationic ISCOM or comprising at least one saponin and at least one sterol, as well as a process for preparation of the compositions. The invention further provides constructs comprising these compositions. The compositions and constructs may be used in methods for generating an immunological response, methods for treating or preventing a condition of illness and methods for vaccination. The occlusion vehicle is e.g. a pressure sensitive adhesive, such as a hydrocolloid adhesive or a hydrogel adhesive, which may be cross-linked, or the occlusion vehicle may be non-adherent.