New efficient near-IR photosensitizer based on bacteriochlorin p N-methoxycycloimide oxyme methyl ester

This work is devoted to investigation of new photosensitizer Bacteriochlorin p N-methoxycycloimide oxyme methyl ester (BchlpOx-NOMe). Investigations of photosensitizer in vivo and experimental PDT were performed on animals bearing intramuscularly inoculated Erlich tumor and B16 melanoma. Characteristic absorption maximum of BchlpOx-NOMe around 795 nm is within the range of minimum intrinsic absorption of biological tissue. Dynamics and selectivity of sensitizer accumulation in tumor and normal tissue were estimated from spectra of absorption of sensitized tissue in vivo. The investigation has shown that the optimum time range to start PDT irradiation of tumor is 10-30 min after administration. Photosensitizer has shown high photodynamic efficiency of relatively large tumors, including high PDT efficiency in preliminary experiments with BDF1 mice bearing B16 melanoma, causing tumor growth inhibition more than 90% and prolongation of lifespan of tumor-bearing animals more than 60%.