Photodynamic therapy (PDT) is a new modality for the treatment of diseases which involves the rapid proliferation of cells such as; cancer, psoriasis, proliferative diabetic retinopathy, restenosis and benign prostate hyperplasia. While a small number of photosensitizing compounds are being evaluated for use in PDT, research into new compounds that show improvements in efficacy over existing drugs needs to be undertaken. Structure-activity relationships are not well established in this therapy and unless concerted efforts are undertaken to determine what factors influence activity, one can not begin to rationally design drugs that will be predictably effective in the treatment of the diseases mentioned above. A goal of this project is to develop new sensitizers that possess different functionality which may aid in the understanding of factors which influence drug efficacy. These compounds will be evaluated using both in vitro and in vivo model systems. Properties such as dark toxicity, light toxicity, cell uptake, and tumor phototoxicity will be evaluated. Compounds that show promise will be further evaluated in detailed preclinical studies. PROPOSED COMMERCIAL APPLICATION: PDT has a wide range of applications that make in unique in the field of photosensitized medicine. Several important diseases are currently being targeted for PDT application by several companies world wide. Of these diseases, those applications most actively being pursued (but not limited to) are in the areas of; cancers, skin diseases, neovascular eye diseases, cardiovascular disease and urological disorders.