# US 9,517,267 B2 · Photodynamic diagnostic agent and photobleaching inhibitor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,517,267 B2 - Document ID: US9517267B2 - Status: Granted - Kind: B2 - Application number: 14/373,341 - Filed: 2013-01-22 - Published: 2015-10-22 - Granted: 2016-12-13 - Earliest claimed: 2012-01-26 - Assignees: SBI Pharmaceuticals Co., Ltd.; Tokyo Institute of Technology - Applicants: SBI Pharmaceuticals Co., Ltd.; Tokyo Institute of Technology - Inventors: Masahiro Ishizuka; Tohru Tanaka; Shun-ichiro Ogura; Takuya Ishii - Web page: https://patentgrep.com/patent/US9517267B2 ## CPC - A61K 41/0061: {5-aminolevulinic acid-based PDT: 5-ALA-PDT involving porphyrins or precursors of protoporphyrins generated in vivo from 5-ALA} - A61K 31/216: of acids having aromatic rings, e.g. benactizyne, clofibrate - A61K 41/0057: {Photodynamic therapy with a photosensitizer, i.e. agent able to produce reactive oxygen species upon exposure to light or radiation, e.g. UV or visible light; photocleavage of nucleic acids with an agent} - A61K 45/06: Mixtures of active ingredients without chemical characterisation, e.g. antiphlogistics and cardiaca - A61K 49/0036: {Porphyrins (used in photodynamic therapy A61K41/0071 or A61K41/0076; used as targeting group or modifying agent for targeting a therapeutic compound A61K47/546)} - C07C 69/84: of monocyclic hydroxy carboxylic acids, the hydroxy groups and the carboxyl groups of which are bound to carbon atoms of a six-membered aromatic ring - A61K: PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES (devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms A61J3/00; chemical aspects of, or use of materials for deodorisation of air, for disinfection or sterilisation, or for bandages, dressings, absorbent pads or surgical articles A61L; soap compositions C11D) - C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS ## Abstract The objects of the present invention are to inhibit photobleaching of porphyrins as well as to provide a superior photodynamic diagnostic agent and a photodynamic diagnostic method employing the photobleaching inhibitor for porphyrins. The present invention provides a photodynamic diagnostic agent containing a precursor of porphyrins and a gallic acid. The present invention also provides a photobleaching inhibitor for porphyrins containing a gallic acid. ## Claims ### Claim 1 A method for detecting a porphyrin accumulation site, comprising: irradiating a subject with the excitation light for porphyrins, wherein said subject has been administered in advance of said irradiation a precursor of porphyrins and a compound of the following formula (I): wherein R1 is selected from the group consisting of an alkyl group having 1-10 carbons, a cycloalkyl group having 3-8 carbons, an aryl group having 6-14 carbons, and an aralkyl group having 7-15 carbons, and R2, R3, and R4 each represent a hydroxyl group, or a salt thereof, said precursor of porphyrins and compound of formula (I) having been administered to said subject at simultaneous or different times, and detecting the fluorescence of porphyrins, thereby detecting the porphyrin accumulation site. ### Claim 2 A photodynamic diagnostic method for measuring a range of a lesion site in a subject, comprising: administering to said subject a precursor of porphyrins and a compound of the following formula (I): wherein R1 is selected from the group consisting of an alkyl group having 1-10 carbons, a cycloalkyl group having 3-8 carbons, an aryl group having 6-14 carbons, and an aralkyl group having 7-15 carbons, and R2, R3, and R4 each represent a hydroxyl group or a salt thereof, at simultaneous or different times, irradiating the subject with the excitation light for porphyrins, identifying the porphyrins accumulation site by detecting the fluorescence of porphyrins, and measuring the range of the lesion site. ### Claim 3 (depends on 1) The method according to claim 1, wherein R1 is selected from the group consisting of a methyl group, a propyl group, a butyl group, and an octyl group. ### Claim 4 (depends on 2) The method according to claim 2, wherein R1 is selected from the group consisting of a methyl group, a propyl group, a butyl group, and an octyl group. ### Claim 5 (depends on 1) The method according to claim 1, wherein said precursor of porphyrins is a 5-aminolevulinic acid (ALA). ### Claim 6 (depends on 2) The method according to claim 2, wherein said precursor of porphyrins is a 5-aminolevulinic acid (ALA). ### Claim 7 (depends on 1) The method according to claim 1, wherein said precursor of porphyrins is a compound of the following formula (II): R1—NHCH2COCH2CH2COOR2 (II), wherein R1 represents a hydrogen atom or an acyl group, and R2 represents a hydrogen atom, a linear or branched alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group, or a salt thereof. ### Claim 8 (depends on 2) The method according to claim 2, wherein said precursor of porphyrins is a compound of the following formula (II): R1—NHCH2COCH2CH2COOR2 (II), wherein R1 represents a hydrogen atom or an acyl group, and R2 represents a hydrogen atom, a linear or branched alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group, or a salt thereof. ### Claim 9 (depends on 1) The method according to claim 1, wherein said porphyrins are selected from the group consisting of protoporphyrin IX, uroporphyrin I, uroporphyrin III, coproporphyrin I, coproporphyrin III, heptacarboxylporphyrin I, heptacarboxylporphyrin III, hexacarboxylporphyrin I, hexacarboxylporphyrin III, pentacarboxylporphyrin I, pentacarboxylporphyrin III, isocoproporphyrin, harderoporphyrin, isoharderoporphyrin, mesoporphyrin IX, deuteroporphyrin IX, and pemptoporphyrin. ### Claim 10 (depends on 2) The method according to claim 2, wherein said porphyrins are selected from the group consisting of protoporphyrin IX, uroporphyrin I, uroporphyrin III, coproporphyrin I, coproporphyrin III, heptacarboxylporphyrin I, heptacarboxylporphyrin III, hexacarboxylporphyrin I, hexacarboxylporphyrin III, pentacarboxylporphyrin I, pentacarboxylporphyrin III, isocoproporphyrin, harderoporphyrin, isoharderoporphyrin, mesoporphyrin IX, deuteroporphyrin IX, and pemptoporphyrin. ### Claim 11 (depends on 9) The method according to claim 9, wherein said porphyrins are protoporphyrin IX (PpIX). ### Claim 12 (depends on 10) The method according to claim 10, wherein said porphyrins are protoporphyrin IX (PpIX).