The present disclosure relates to a method for treating diabetic macular edema (DME) and/or retinal vein occlusion (RVO) comprising administering to the retina of a patient in need thereof an effective amount of a caspase-9 signaling pathway inhibitor. The caspase-9 signaling pathway inhibitor may include a peptide caspase-9 inhibitor and/or may be conjugated to a cell-penetrating peptide. The present disclosure further includes pharmaceutical compositions including a caspase-9 signaling pathway inhibitor. The disclosure further relates to the use of such compositions in a method for treating DME and/or RVO.