Abstract: Disclosed are water-soluble gel-based compositions for the delivery of recombinant adeno-associated virus (rAAV) vectors that express nucleic acid segments encoding therapeutic constructs including peptides, polypeptides, ribozymes, and catalytic RNA molecules, to selected cells and tissues of vertebrate animals. Also disclosed are gel-based rAAV compositions are useful in the treatment of mammalian, and in particular, human diseases, including for example, cardiac disease or dysfunction, and musculoskeletal disorders and congenital myopathies, including, for example, muscular dystrophy, acid maltase deficiency (Pompe's disease), and the like. In illustrative embodiments, the invention provides rAAV vectors comprised within a biocompatible gel composition for enhanced viral delivery/transfection to mammalian tissues, and in particular to vertebrate muscle tissues such as a human heart or diaphragm tissue.