The present invention provides a mechanism which enables the body to produce lasting supply of PYY as a clinical alternative to dispensing devices or slow release formulations capable of sustained drug delivery by developing recombinant adena associated virus (rAAV) vector for stable delivery of genes to a variety of cell types. The present invention also provides for a method of treating obesity and accompanying metabolic disorders by injecting the target tissue of the subject with a rAAV plasmid comprising a DNA cassette for expression of PYY or a PYY agonist.