# US 8,916,205 B2 · Polymeric nanoparticles for photosensitizers

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 8,916,205 B2
- Document ID: US8916205B2
- Status: Granted
- Kind: B2
- Application number: 14/236,212
- Filed: 2011-08-11
- Published: 2014-06-19
- Granted: 2014-12-23
- Earliest claimed: 2011-08-11
- Assignees: Quest Pharmatech Inc.
- Applicants: Azita Haddadi; Ragupathy Madiyalakan; Thomas Woo
- Inventors: Azita Haddadi; Ragupathy Madiyalakan; Thomas Woo
- Web page: https://patentgrep.com/patent/US8916205B2

## CPC

- 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 9/0014: {Skin, i.e. galenical aspects of topical compositions (non-active ingredients are additionally classified in A61K47/00; A61K9/0009, A61K9/0021, A61K9/7015, A61K9/7023 take precedence; cosmetic preparations A61K8/00, A61Q; preparations for wound dressings or bandages A61L26/00)}
- A61K 9/0019: {Injectable compositions; Intramuscular, intravenous, arterial, subcutaneous administration; Compositions to be administered through the skin in an invasive manner (non-active ingredients are additionally classified in A61K47/00)}
- A61K 9/06: Ointments; Bases therefor; {Other semi-solid forms, e.g. creams, sticks, gels (composition of ointments, creams or gels A61K47/00)}
- A61K 9/5153: {Polyesters, e.g. poly(lactide-co-glycolide)}
- A61K 31/122: having the oxygen directly attached to a ring, e.g. quinones, vitamin K1, anthralin
- A61P 35/00: Antineoplastic agents
- C07C 49/84: containing ether groups, [IMAGE cpc-sch-C07C-0958.gif] groups,[IMAGE cpc-sch-C07C-0959.gif] groups, or[IMAGE cpc-sch-C07C-0960.gif] groups
- Y10S 977/773: Nanoparticle, i.e. structure having three dimensions of 100 nm or less
- 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)
- A61P: SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
- C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS
- Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS

## Abstract

Biodegradable polymeric nanoparticles comprising an inner core formed of a photodynamic agent capable of being activated to generate cytotoxic singlet oxygen are prepared. These nanoparticles have anti-cell proliferation activity and are useful in treating both cancerous and non-cancerous conditions including actinic keratosis, psoriasis and acne vulgaris. Preferably, the photodynamic agent is a hypocrellin B derivative while the polymeric nanoparticle comprises polyglycolic acid, polylactic acid or poly(lactide-co-glycolide). Hypocrellin-comprising nanoparticles are demonstrated to be activated by light or hydrogen peroxide.

## Claims

### Claim 1

A method for providing singlet oxygen for anti-cell proliferation activity topically to target tissue comprising the steps of:
a) contacting said tissue with an effective amount of a biodegradable polymeric nanoparticle comprising:
an inner core formed of a photodynamic agent selected from the group consisting of
or a combination thereof, and
a polymer selected from the group consisting of polyglycolic acid, polylactic acid or a poly(lactic-co-glycolic acid); and
b) contacting said tissue with hydrogen peroxide.

### Claim 2 (depends on 1)

The method of claim 1, wherein the polymer comprises poly(lactic-co-glycolic acid) having an ester-terminus.

### Claim 3 (depends on 1)

The method of claim 1, wherein the polymer comprises poly(lactic-co-glycolic acid) having a free carboxylic acid terminus.

### Claim 4 (depends on 1)

The method of claim 1, wherein the nanoparticles have an average diameter that is approximately 100-400 nm.

### Claim 5 (depends on 4)

The method of claim 4, wherein the nanoparticles have an average diameter of approximately 200 nm.