Use of monoolein in the treatment of the periodontal pocket

Abstract: This invention relates to compositions and methods for treating diseases of the oral cavity in humans and lower animals using a glycerol monooleate gel for releasing drugs in the oral cavity.

Description: This invention relates to compositions for treating diseases of the oral cavity, which compositions are placed in or around the periodontal pocket. Periodontal disease, for example, is a major cause of tooth loss in adults. Tooth loss from periodontal disease is a significant problem beginning at age 35, but even by age 15 it is estimated that about 4 out of 5 persons already have gingivitis and 4 out of 10 have periodontitis. While good oral hygiene, as achieved by brushing the teeth with a cleansing dentifrice, may help reduce the incidence of periodontal disease, it does not necessarily prevent or eliminate its occurrence. This is because microorganisms contribute to both the initiation and progress of periodontal disease. Thus, in order to prevent or treat periodontal disease, these microorganisms must be suppressed by some means other than simple mechanical scrubbing. Towards this end, there has been a great deal of research aimed at developing therapeutic dentifrices, mouthwashes, and methods of treating periodontal disease which are effective in suppressing these microorganisms. Recent developments in the art are directed toward delivering the therapeutic agent directly to the periodontal pocket, in some cases in a controlled release formulation. Gordon et al. have described the use of a drug-filled polymer hollow fiber. (J.M. Goodson et al., "Periodontal Therapy by local Delivery of Tetracycline", J. Clin. Periodontal . 6, 83 (1979), J. Lindhe et al., "Local Tetracycline Delivery Using Hollow Fiber Devices in Periodontal Therapy", J. Clin. Periodontal . 6, 141 (1979) and R.L. Dunn et al., "Monolithic Fibers for Controlled Delivery of Tetracycline", in Proc. Ninth Int. Symposium on Controlled Release of Bioactive Materials , Ft. Lauderdale, FL, July (1982). This device is tied around a tooth and gently pressed below the margin of the gingiva so that it resides in the periodontal pocket, and is capable of delivering an effective dose of 2.5 micrograms of tetracycline per day per periodontal pocket for a prolonged period of a week or more. Similar results have been obtained by Coventry and Newman (J. Coventry and H. N. Newman, "Experimental Use of a Slow Release Device Employing Chlorhexidine Gluconate in Areas of Acute Periodontal Inflammation", J. Clin. Periodontal . 9, 129 (1982) and Addy et al. (M. Addy et al., "The Development and in vitro Evaluation of Acrylic Strips and Dialysis Tubing for Local Drug Delivery", J. Periodontal 53, 693 (1982) using acrylic strips 1 mm or more long, impregnated with chlorhexidine, tetracycline or metronidazole, which were inserted into the periodontal pocket with tweezers. Such a strip, formed from ethylcellulose impregnated with metronidazole, is disclosed by Loesche in US-A-4,568,538 (February 1986). Another strip, employing a water soluble polymer of a particular elasticity and viscosity, is disclosed by Suzuki et al. in US-A-4,569,837 . In addition to the above approaches, the prior art also discloses using putty-like compositions containing an antimicrobial for insertion into the periodontal pocket. See US-A-4,650,665 , March 17, 1987 to Kronenthal et al.. Gel forming materials like hydroxypropyl methyl cellulose or pluronic F-127 polyol have been utilized in the past without success. It has been found that instead of using such hydrophilic or water soluble materials, desirable physical properties, convenience of placement and duration of retention can also be achieved by using materials that have limited water solubility. What is surprising, however, is that some of these materials are capable of absorbing water and undergoing increase in viscosity, providing a most desirable feature to treat disorders of the oral cavity. EP-A-0,267,617 discloses a penetration-enhancing pharmaceutical composition for topical application to the skin comprising 0.01-50% of active and 40-99.99% of a penetration-enhancing vehicle comprising one or more cell-envelope disordering compounds which can be glycerol monooleate and a lower alcohol in a ratio of between 50:1 and 1:50. There is no disclosure or suggestion of the rapid gelling mechanism exhibited by the monoolein gelling agent when placed under the conditions found in the periodontal pocket of the oral cavity or of the benefit of this rapid gelation behaviour in terms of providing compositions having extended duration of retention at the treatment site and controlled release of active. US-A-2,976, 251 relates to glycerol fatty acid partial ester compositions, especially to high purity monoglyceride compositions for use as carrier materials for medicaments. In addition, there is disclosure of firm, substantially clear gels which contain glycerol fatty partial ester compositions and from 10% to 90% water. It is to be noted that the gel compositions disclosed are prepared before being applied to the body as cosmetics, medicaments, etc. In addition, the gels are prepared by heating with water at temperatures from 50°C to 90°C (Column 4, lines 32 and 69). However, there is no disclosure or indication whatsoever in this document of the use of monoolein which is free of water for providing compositions which rapidly gel by water absorption "in situ" i.e. when placed in the periodontal pocket of the mouth, or of the benefits provided in terms of controlled delivery of active and improved retention at the treatment site. The present inventor has discovered that compositions employing glycerol monooleate (monoolein) gels provide for easy placement in and around the periodontal pocket and good drug release. When a material such as monoolein is compounded with an active agent and placed into or around the periodontal cavity, it absorbs water from the surrounding body fluid and becomes more viscous. Since monoolein is not miscible with water, it provides extended duration of retention at the site of treatment. The active agent is slowly released from the composition in a controlled manner over extended duration. It is therefore an object of the present invention to provide a use of monoolein in the manufacture of compositions suitable for treating diseases of the oral cavity. It is a further object of the present invention to provide such use wherein the monoolein compositions additionally employ a polymer. All percentages and ratios used in here are by weight unless otherwise indicated. All measurements are made at 25°C unless otherwise indicated. According to the present invention there is provided a use of monoolein in the manufacture of a composition suitable for insertion into or around the periodontal pocket of a person or lower animal suffering from diseases of the oral cavity wherein the composition consists of from 1% to 99% by weight of monoolein gelling agent, from 1% to 90% by weight of a drug active selected from antiinflammatory agents, antimicrobials, antibiotics, peroxides, anesthetic agents and vitamins and optional components selected from surfactants, viscosity controlling agents, complexing agents, antioxidants, polymers, gums and waxes/oils and wherein in use the monoolein gelling agent is capable of absorbing water from the body fluid of the periodontal pocket thereby undergoing increase in viscosity. The essential as well as optional components of the compositions herein are described below. Monoolein The gelling agent used in the present invention is a monooleate ester of glycerol (monoolein). Monoolein is an item of commerce and is available from C. P. Hall and Co. as CPH-362-N. This agent can easily be formulated with the drug active and be easily positioned into and around the periodontal pocket. Monoolein comprises the bulk of the compositions herein. The amount employed is in the range of from 1% to 99%, preferably from 10% to 90%, most preferably from 20% to 80%. Drug Active The drugs used in the present compositions are selected from antimicrobial agents such as iodine, sulfonamides, mercurials, bisbiguanides, or phenolics; antibiotics such as tetracycline, neomycin, kanamycin, metronidazole, or clindamycin; antiinflammatory agents such as aspirin, naproxen, ibuprofen, flurbiprofen, indomethacin, eugenol, or hydrocortisone; anesthetic agents such as lidocaine or benzocaine; vitamins; and peroxides such as urea peroxide. It is recognized that in certain forms of therapy, combinations of these agents in the same delivery system may be useful in order to obtain an optimal effect. Thus, for example, an antibacterial and an anti inflammatory agent may be combined in a single delivery system to provide combined effectiveness. The drug active is used at a level of from 1% to 90%, preferably from 5% to 50% of the compositions. Compositions can be desirably tailored to provide sustained retention and slow release of one or more actives at the treatment site, by varying the ratios of components and, quantity of the product applied at the treatment site. Optional Components In addition to the drug active, the compositions herein may include a variety of optional components. Such components are selected from surfactants, viscosity controlling agents, complexing agents, antioxidants, other polymers such as carboxymethyl cellulose, gums such as guar gum, waxes/oils such as castor wax, castor oil, glycerol, dibutyl phthalate and di(2-ethylhexyl phthalate). If used, these optional components comprise from about 0.1% to about 20%, preferably from about 0.5% to about 5% of the total composition. METHOD OF MANUFACTURE Methods of manufacturing the compositions herein are disclosed in the Examples. EXAMPLE I The following is an exemplary composition manufactured herein : Weight % Tetracycline hydrochloride 49.9 Hydroxypropyl cellulose 2.5 Glycerol monooleate 47.6 The above composition can be prepared in a number of different ways. One way is as follows: The monooleate is heated to about 50°C. The hydroxypropyl cellulose is then added in powdered form and dissolved. The drug is added and mixed until uniform. The mixture is then cooled and packaged. The compositions herein are inserted into or around the periodontal pocket or gingival region, and are administered in the form of a gel which sets up. The composition can be put into or around the pocket in any number of ways such as with a syringe. EXAMPLE II Given below is another composition manufactured herein : Wt. % Clindamycin phosphate 35 Hydroxypropyl cellulose 5 Lecithin 25 Glycerol monooleate 30 Polyethylene glycol-400 5 EXAMPLE III Given below is still another composition manufactured herein: Wt. % Metronidazole 30 Hydroxypropyl cellulose 2 Lecithin 15 Glycerol monooleate 53

Claims: Use of monoolein in the manufacture of a composition suitable for insertion into or around the periodontal pocket of a person or lower animal suffering from diseases of the oral cavity wherein the composition consists of from 1% to 99% by weight of monoolein gelling agent, from 1% to 90% by weight of a drug active selected from antiinflammatory agents, antimicrobials, antibiotics, peroxides, anesthetic agents and vitamins and optional components selected from surfactants, viscosity controlling agents, complexing agents, antioxidants, polymers, gums and waxes/oils and wherein in use the monoolein gelling agent is capable of absorbing water from the body fluid of the periodontal pocket thereby undergoing increases in viscosity. Use of monoolein according to Claim 1 wherein the concentration of the drug active is from 5% to 50% and the active is selected from the tetracycline group of antibiotics. Use of monoolein according to Claim 1 or 2 which in addition contains a polymer. Use of monoolein according to any of Claims 1-3 wherein the monoolein concentration is from 20% to 80%. Use of monoolein according to any of Claims 1-4 wherein the drug active is an antiinflammatory agent. Use of monoolein according to any of Claims 1-5 wherein the drug active is a bisbiguanide compound.

Inventors: DAMANI NALINKANT CHUNILAL, DAMANI, NALINKANT CHUNILAL
Applicants: PROCTER & GAMBLE, THE PROCTER & GAMBLE COMPANY
Application year: 1990
Main classification: A61K9
IPC codes: A61P1, A61K9, A61K45, A61K31, A61K47