US Patent 9402919 Vectors conditionally expressing protein

This invention relates to the field of therapeutics. Disclosed are methods of conditionally expressing erythropoietin under the control of an ecdysone receptor-based gene expression modulation system in the presence of activating ligand and uses for therapeutic purposes in animals. The methods of the invention cause an in vivo increase in the expression of erythropoietin and an increase in the hematocrit or volume percentage of red blood cells in blood after administration of the ligand.