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Details for Patent: 4,932,934

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Summary for Patent: 4,932,934

Title:	Methods for treatment of tumors
Abstract:	To obtain tumor-selective, photosensitizing drugs useful in the localization of neoplastic tissue and treatment of abnormal neoplastic tissue such as tumors, one of two methods is used. In the first method, a hydrolyzed mixture of the products of reaction of hematoporphyrin with acetic acid and sulfuric acid is cycled through a microporous membrane system to exclude low molecular weight products. In the second method, drugs are synthesized or derived from other pyrrole compounds. The drugs: (1) include two covalently bound groups, each with four rings, some of which are pyrroles such as phlorins, porphyrins, chlorins, substituted pyrroles, substituted chlorins or substituted phlorins, each group being arranged in a ring structure, connected covalently to another group and have a triplet energy state above 37.5 kilocalories per mole; (2) are soluble in water, forming an aggregate of over 10,000 molecular weight in water and have an affinity for each other compared to serum protein such that 10 to 100 percent remain self aggregated in serum protein; and (3) are lipophillic and able to disaggregate and attach to cell plasma, nuclear membrane, mitochondria, lysosomes and tissue. The drug obtained by the first method has an empirical formula of approximately C.sub.68 H.sub.70 N.sub.8 O.sub.11 or C.sub.68 H.sub.66 N.sub.8 O.sub.11 Na.sub.4. Neoplastic tissue retains the drug after it has cleared normal tissues and illumination results in necrosis. Moreover, other photosensitizing materials may be combined with a carrier that enters undesirable tissues and cells of the reticular endothelial system such as macrophages. These photosensitizing materials: (1) must have a triplet energy state above 3.5 kilocalories per mole; (2) cannot be easily oxidized; and (3) not physically quench any required energy state. Preferably, this photosensitizing material should be lipophilic.
Inventor(s):	Dougherty; Thomas J. (Grand Island, NY), Potter; William R. (Grand Island, NY), Weishaupt; Kenneth R. (Sloan, NY)
Assignee:	Health Research, Inc. (Buffalo, NY)
Application Number:	07/236,603
Patent Claim Types: see list of patent claims	Process; Composition; Use;

Drugs Protected by US Patent 4,932,934

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Patent Submitted

International Patents Family Members for US Patent 4,932,934

Country	Document Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Japan	2532368
European Patent Office	0161606
European Patent Office	0120054
Canada	1275452