Drug – bio-affecting and body treating compositions – Designated organic active ingredient containing – Peroxide doai
Reexamination Certificate
2000-05-08
2002-08-13
Seidel, Marianne C. (Department: 1614)
Drug, bio-affecting and body treating compositions
Designated organic active ingredient containing
Peroxide doai
C514S859000, C424S047000, C424S062000, C424S230100
Reexamination Certificate
active
06433024
ABSTRACT:
TECHNICAL FIELD OF THE INVENTION
This invention relates to topical compositions for the treatment of acne.
BACKGROUND OF THE INVENTION
Acne and seborrhea are conditions of the skin characterized by an excessive flow of sebum from the sebaceous glands. Sebum reaches the skin surface through the duct of the hair follicle. The presence of excessive amounts of sebum in the duct and in the skin acts to block the continuous flow of sebum from the follicular duct. This produces a thickening of the sebum which becomes a comedone. Comedone formation is followed by hyperkeratinization of the follicular opening, completely closing the duct. The usual result is a papule, a pustule, or a cyst, often contaminated with bacteria which cause secondary infections.
Many topical therapeutic agents are used in the treatment of acne and seborrhea to prevent the blocking of the follicular duct, to reopen the duct once it has become blocked, to act against the infecting bacteria or the thickened sebum, or to provide combinations of each of these actions. Therapeutic agents which act to prevent the blocking of the follicular duct by promoting the removal or scuffing off of excess keratin are known as keratolytic agents. For example, the use of sulfur as a mild irritant to remove the horny layer of skin, and with it the debris clogging the follicular openings, is well known.
Several anti-acne agents are well known in the art. These include, for example, benzoyl peroxide, alpha hydroxy acids and detergents. Benzoyl peroxide is a colorless, odorless, tasteless crystalline solid that is stable at ordinary room temperatures. It is also a strong oxidizing agent which may be used as an antibacterial and keratolytic agent in the treatment of acne. Finely divided benzoyl peroxide often is incorporated in a cream or ointment for convenience in applying it to the skin. However, because of the powerful oxidizing properties of benzoyl peroxide, the inclusion of it in conventional ointment or cream bases often results in unstable compositions that display an unacceptably rapid loss in keratolytic potency. A stable benzoyl peroxide composition that is very effective in the treatment of acne and that has a projected shelf life of over eight years is described in U.S. Pat. No. 3,535,422 (the '422 patent) to Cox and Cuifo. The '422 patent describes a uniform dispersion of finely benzoyl peroxide particles in an emulsion of water and certain selected organic emollients. When the composition is applied to the patient's skin the water content of the emulsion evaporates leaving most of the organic emollients and the benzoyl peroxide particles on the surface of the skin near and in contact with the acne sites.
Benzoyl peroxide has been reported to be irritating to skin when applied at concentrations appropriate for the treatment of acne. The same is true of detergent-based anti-acne compositions. For example, detergent compositions based upon salts of lauryl sulfates (e.g., ammonium lauryl sulfate) are known to cause skin irritation.
Consequently, anti-acne compositions containing benzoyl peroxide and/or detergents often contain one or more moisturizers in order to minimize skin irritation associated with the anti-acne agent.
U.S. Pat. No. 4,056,611 discloses the use of benzoyl peroxide for the treatment of acne. The compositions also contain a surface active agent, an alkyl alcohol and water.
U.S. Pat. No. 4,105,782 discloses the use of amide and/or ammonium salts of &agr;- and &bgr;-hydroxy acids and &agr;-keto acids for the treatment of acne. The acne treatment compounds disclosed in the '782 patent include the amide and/or ammonium salts of citric acid, glycolic acid, glucuronic acid, galacturonic acid, glucuronolactone, gluconolactone, &agr;-hydroxybutyric acid, &agr;-hydroxyisobutyric acid, malic acid, mandelic acid, pyruvic acid and several others.
U. S. Pat. No. 4,923,900 discloses compositions containing benzoyl peroxide, water and a water miscible solvent having a boiling point greater than that of water. Dimethylisosorbide is disclosed as a particularly preferred solvent in the disclosed compositions. The disclosed compositions are said to be useful for the treatment of skin conditions such as acne and seborrhea, dermatophyte infection, reactions to irritative plant contactants such as the oleoresins of poison ivy, and development offensive body odor.
PanOxyl Bar® is a commercial product that is known for the treatment of acne. In addition to containing benzoyl peroxide, it also contains cetearyl alcohol, cocamidopropyl betaine, corn starch, glycerin, hydrogenated castor oil, lactic acid, mineral oil, optical brighteners, PEG-14M, potassium lauryl sulfate, potassium phosphate, silica, sodium lauryl sulfate, sodium sulfate, titanium dioxide and water. The consistency of PanOxyl Bar® is similar to that of bar soap.
None of the compositions of the aforementioned references provide a benzoyl peroxide composition which combines the desired anti-acne properties with the desired non-irritating properties in a cream-like formulation.
Accordingly, an object of the present invention is to provide a stable topical composition for the treatment of acne that is less irritating or is perceived to be less irritating than topical anti-acne compositions in the prior art.
A further object of the present invention is to provide a method for treating acne by applying to the affected areas of a patient's skin a topical anti-acne composition that is less irritating or perceived to be less irritating than compositions in the prior art.
SUMMARY OF THE INVENTION
The present invention is directed towards a topical composition for the treatment of acne comprising water, an organic peroxide, an alpha hydroxy acid, a moisturizer, an isosorbide and a detergent. This invention also is directed towards a method of making the composition of this invention. The method involves (1) heating water to between 60° C. and 70° C.; (2) adding a detergent base to the water and mixing the solution; (3) cooling the solution and adding an alpha hydroxy acid, an isosorbide and sodium pyrollidone carboxylate; (4) continuing to cool the solution to between 25° C. and 35° C. and then adding benzoyl peroxide and a preservative to the solution; (5) mixing and milling the product until smooth; and (6) adjusting the pH of the product to a pH of 3-5 with a base. This invention also is directed towards a method for treating a patient afflicted with acne by applying the composition of this invention to the affected areas of the patient's skin.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Benzoyl peroxide is a strong oxidizing agent which may be used in topical compositions for treating acne. However, when applied at concentrations that are effective for treating acne, benzoyl peroxide also may be irritating to the skin. Consequently, many compositions that contain benzoyl peroxide also include one or more moisturizers. Unfortunately, moisturizers often interfere with benzoyl peroxide's ability to be in contact with the skin, and thereby reduce its effectiveness in treating acne. This often occurs with oil-based moisturizers, such as isopropyl myristate, mineral oil or petrolatum.
The present invention is based in part on the use of more water-soluble moisturizers in combination with benzoyl peroxide. These moisturizers, such as, for example, dimethyl isosorbide and sodium pyrollidone carboxylate, reduce skin irritation associated with benzoyl peroxide but do not significantly reduce benzoyl peroxide's effectiveness in treating acne. Without wishing to be bound by theory, it is believed that these more water-soluble moisturizers may assist in solubilizing benzoyl peroxide in water without interfering with benzoyl peroxide's ability to be in contact with the skin.
Surprisingly, the present inventors have found that when combined with benzoyl peroxide in a pharmaceutically acceptable carrier, sodium pyrollidone carboxylate may be used alone or in combination with an alpha hydroxy acid (e.g., glycolic acid) or an alkyl est
Popp Karl F.
Stiefel Brent D.
Kwon Brian-Yong S.
Lott & Friedland, P.A.
Seidel Marianne C.
LandOfFree
Topical anti-acne composition does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Topical anti-acne composition, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Topical anti-acne composition will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2949403