The study will be an open-label, single-masked, randomized Phase I study that will investigate the safety and potential efficacy of the new formulation of TAC-PF. Sixteen participants with retinal vascular disease will be randomly assigned to receive via intravitreal injection at one of 4 dose levels (1 mg, 4 mg, 8 mg, or 16 mg) of TAC-PF. Depending on a participant's response, injections may be repeated at up to 3 month intervals. Participants will be followed for 3 years.