The present invention relates to methods of inducing the self-renewal of stem/progenitor supporting cells, including inducing the stem/progenitor cells to proliferate while maintaining, in the daughter cells, the capacity to differentiate into hair cells. Specifically, the invention relates to methods of using compounds comprising a 2-pyrimidinylaminoethylamino-2-pyridyl moiety having a Formula Iand pharmaceutically acceptable salts thereof.