Synergistic Antimicrobial Preparations Containing Chlorite and Hydrogen Peroxide

Abstract

Antimicrobial / pharmaceutical preparations (e.g., solutions, gels, ointments, creams, sustained release preparations, etc.) which comprise chlorite (e.g., a metal salt of a chlorite) in combination with a peroxy compound (e.g., hydrogen peroxide), and methods for using such preparations for disinfection of articles or surfaces (e.g., contact lenses, counter tops, etc.), antisepsis of skin or other body parts, prevention or deterrence of scar formation and / or treatment and prophylaxis of dermal (i.e., skin or mucous membrane) disorders (e.g., wounds, burns, infections, cold sores, ulcerations, psoriasis, acne, or other scar-forming lesions).

Description

RELATED APPLICATIONS[0001]This is a continuation of copending U.S. patent application Ser. No. 10 / 938,797 filed Sep. 9, 2004, which is a continuation of U.S. patent application Ser. No. 10 / 308,229 filed Dec. 2, 2002, which is a continuation of U.S. patent application Ser. No. 09 / 722,919 filed Nov. 27, 2000 and issued as U.S. Pat. No. 6,488,965, which is a continuation of U.S. patent application Ser. No. 09 / 169,620 filed Oct. 8, 1998, the entire disclosure of each such patent and application being expressly incorporated herein by reference.FIELD OF THE INVENTION[0002]The present invention relates generally to medical compositions and methods, and more particularly to certain disinfectant / antimicrobial preparations and methods for using such preparations i) to disinfect articles or surfaces, ii) as a topical antiseptic for application to body parts, and iii) to prevent or deter scar formation and iv) to treat dermatological disorders such as wounds, burns, ulcers, psoriasis, acne and ...

AI Technical Summary

Benefits of technology

[0031]The present invention provides antimicrobial preparations (e.g., solutions, gels, ointments, creams, etc.) for disinfection of articles or surfaces (e.g., contact lenses, counter tops, etc.), antisepsis of skin or other body parts, prevention or minimization of scarring, and / or treatment or prophylaxis of dermal (Le., skin or mucous membrane) disorders (e.g., wounds, burns, infections, cold sores, ulcerations, psoriasis, scar forming lesions, acne). The antimicrobial preparations of this invention generally comprise from about 0.001% to about 0.10 by weight of a metal chlorite in combination with from 0.001% to 0.05% of a peroxy compound such as hydrogen peroxide. Additionally, the chlorite / peroxide preparations of the present invention may contain additional components such as polymeric lubricants and surfactants, and / or may be formulated in a polymeric drug delivery system or liposomal preparation. The chlorite / peroxide preparations of the present invention have broad antimicrobial activity, including for example activity against gram negative and gram positive bacteria, yeasts and fungi. Moreover, when applied or administered to treat dermal disorders (e.g.,wounds, bums, infections, ulcerations, acne and psoriasis), the chlorite / peroxide preparations of the present invention will not only prevent or lessen microbial infection, but will additionally provide oxygen to the affected tissue, aid in healing and deter scar formation.

Problems solved by technology

Thus, chlorite has not been routinely used as an active microbicidal ingredient in preparations for topical application to the skin.

Concentrated chlorine dioxide in its liquid or gaseous state is highly explosive and poisonous.

For this reason, it is generally not feasible to dispense pure chlorine dioxide for use as a topical antimicrobial agent or disinfectant.

Drawbacks or problems associated with these prior chlorine dioxide generating systems include a) the inconvenience of handing two separate containers or chemical components, b) the difficulty of delivering such two-component systems to the intended site of application, and c) the fact that these prior systems are of acid, rather than neutral, pH.

Moreover, the prior chlorine dioxide generating systems which utilize acid-induced generation of chlorine dioxide can, if uncontrolled, cause the generation of chlorine dioxide to occur quite rapidly and, as a result, the disinfectant or antimicrobial potency of the solution may be short lived.

Increasing the concentration of chlorite and acid within the solution may prolong its disinfectant or antimicrobial shelf life, but such Increased concentrations of these chemicals can result in toxicities or (in topical applications) skin irritation.

Such increased concentrations may also result in the generation of more chlorine dioxide than is required.

However, long term storage and stability are issues with the aqueous solutions described in the above-identified Laso patent, because such mixtures tend to generate chlorine dioxide very quickly, thus diminishing the long term stability of such mixtures.

States that temperatures “much below” 70 degrees C. are ineffective to drive of the free peroxide in the solution and that temperatures should not exceed 92 degrees C. because at higher temperatures the chlorine dioxide will be driven off.

While antibiotics may provide an effective form of treatment, several dangers are often associated with the use of antibiotics in the clinical environment.

These dangers may include but are not limited to: (1) changes in the normal flora of the body, with resulting “superinfection” due to overgrowth of antibiotic resistant organisms; (2) direct antibiotic toxicity, particularly with prolonged use which can result in damage to kidneys, liver and neural tissue depending upon the type of antibiotic; (3) development of antibiotic resistant microbial populations which defy further treatment by antibiotics.

While even minor wounds and abscesses can be difficult to treat in certain patients and / or under certain conditions, there are well known dermal disorders such as psoriasis and dermal ulcerations, which present particular challenges for successful treatment.

Once something triggers a person's genetic tendency to develop psoriasis, it is thought that in turn, the immune system triggers the excessive skin cell reproduction.

However, the effectiveness of the currently accepted treatments for psoriasis is subject to considerable individual variation.

a. Decubitus / Pressure Ulcers—A decubitus ulcer or pressure sore is a lesion caused by unrelieved pressure resulting in damage of the underlying tissue. Decubitus ulcers usually develop over a bony prominence such as the elbow or hip. The unrelieved pressure, along with numerous contributing factors, leads to the skin breakdown and persistent ulcerations.

b. Venous Ulcers—Venous ulcers may result from trauma or develop after chronic venous insufficiency (CVI). In CVI, venous valves don't close completely, allowing blood to flow back from the deep venous system through the perforator veins into the superficialvenous system. Over time, the weight of this column of blood causes fluid and protein to exude into surrounding tissues, resulting in swollen, hyperpigmented ankles, tissue breakdown, and ulceration. Venous ulcers may be shallow or extend deep into muscle.

c. Arterial Ulcers—Leg ulcers also can develop in patients with arterial insufficiency caused by arterial vessel compression or obstruction, vessel wall changes, or chronic vasoconstriction. Smokers face an especially high risk of arterial disease because nicotine constricts arteries, encourages deposits of atherosclerotic plaque, and exacerbates inflammatory arterial disease (Buerger's disease) and vasoconstrictive disease (Raynaud's disease or phenomenon). Arterial ulcers, caused by trauma to an ischemic limb, can be very painful,

However, most diabetic ulcers result from diabetic neuropathy—because the patient can't feel pain in his foot, he's unaware of injuries, pressure from too-tight shoes, or repetitive stress that can lead to skin breakdown.