Devices and methods for delivering a therapeutic agent produced via a genetically-altered chondrocyte are provided. More specifically, the device includes a housing which defines a cell chamber configured to retain a large volume of chondrocytes while selectively releasing therapeutic agents produced via these entrapped cells. In an exemplary embodiment, the cell chamber can be configured such that a portion of cells can be positioned at least about 1.5 mm from an external wall of the device (i.e., about 1.5 mm away from an external nutrient supply). For example, the cell chamber can have a tubular configuration having a length and a diameter wherein each of these dimensions is at least about 3 mm (thereby the central core to the chamber is at least about 1.5 mm from the outer wall of the device).