ENHANCED SKIN PENETRATION SYSTEM FOR IMPROVED TOPICAL DELIVERY OF DRUGS

Abstract: The invention involves pharmaceutical compositions for topical application comprising: (a) a safe and effective amount of a pharmaceutical active; and (b) from about 0.05 % to about 5 % of a non-ionic polyacrylamide having a molecular weight of from about 1,000,000 to about 30,000,000.

Description: ENHANCED SKIN PENETRATION SYSTEM FOR IMPROVED TOPICAL DELIVERY OF DRUGS TECHNICAL FIELD The present invention relates to compositions for the topic administration of drugs, especially such compositions havin enhanced penetration of the drug through the skin. BACKGROUND OF THE INVENTION Because of the accessibility and large area of the skin, i has long been considered a promising route for the administratio of drugs, whether dermal, regional, or systemic effects ar desired. The advantages of the topical route of drug administratio include: avoidance of the risks and inconvenience of parentera treatment; avoidance of the variable absorption and metabolis associated with oral treatment; continuity of drug administration permitting use of pharmacologically active agents with shor biological half-lives; potential reduction of gastrointestina irritation in systemic administration; and treatment of curtaneou manifestations of diseases usually treated systemically. However, the impermeability of skin is well-known, serving a a barrier to ingress of pathogens and toxic chemica s, and egres of physiologic fluids. This impermeability is the result o normal physiologic changes in developing skin. A typical cell i the epidermis is formed in the basal layer. It typically take approximately thirty days for a cell to migrate from the basa layer of the epidermis to sloughing off and discarding at th outer layers of the stratum corneum. As the cell migrates outwar from the basal layer, it progressively keratinizes until it i relatively impermeable. The result is the stratum corneum, a extremely thin surface layer (10 microns) with substantial barrie properties. The cell envelopes of the cells in the stratu corneum tend to be mainly polar lipids, such as ceramides, sterols, and fatty acids while the cytoplasm of stratum corneu cells remains polar and aqueous. Despite the close packing of the cells, some 15% of the stratum corneum is intercellular and, generally, lipid based. It is generally recognized that over the very short term, penetration occurs through the hair follicles and the sebaceous apparatus; long-term penetration occurs across cells (non-polar route). Poor penetration of many drugs across the epidermal lipid barrier has, until now, frustrated attempts to deliver clinically significant doses of many drugs by the topical route. One route of internal delivery of drugs is by transdermal administration. Transdermal administration of drugs can be used in many instances to achieve therapeutic levels of the drugs in the systemic circulatory system, as well as for more localized internal dosing of drugs. Where such therapeutic levels of drugs can be achieved by transdermal administration, several potential advantages exist over other routes of administration. Sustained systemic delivery of drug controlled at therapeutic but below toxic levels over long periods of time with a single continuous application is often an advantage of transdermal drug administra¬ tion. Potential contamination of internal tissues with undesired foreign substances or microbes, often associated with parenteral administration of drugs, is avoided with transdermal drug admin- istration. Oral administration of many drugs is undesirable or unfeasible because the drug decomposes in the harsh environment of the gastrointestinal tract, lacks sufficient absorption from the gastrointestinal tract, or causes gastrointestinal upset or tissue damage in the gastrointestinal tract. First-pass metabolism of orally administered drugs can increase the dosage required to achieve therapeutic levels and thereby increase undesirable side effects either from the primary drug or the metabolites. Main¬ tenance of uniform, optimal systemic levels of drugs for long periods of time is often difficult through oral administration. Such problems can often be reduced or avoided by transdermal drug administration. Despite the substantial potential advantages for transderma administration of drugs, relatively few drugs are so administered The skin is a formidable barrier to the passage of most drugs. I is often necessary to provide a composition containing a ski penetration enhancing vehicle in order to provide sufficien transdermal penetration of the drug to achieve therapeutic level of the drug at the target internal tissue. A number of ski penetration enhancing vehicles for drugs have been disclosed, including those in the following references: U.S. Patent No. 3,536,816 issued to Kellner on October 27, 1970; U.S. Patent No. 4,006,218 issued to Sipos on February 1, 1977; U.S. Patent No. 4,124,720 issued to Wenmaekers on November 7, 1978; U.S. Patent No. 4,126,681 issued to Reller on November 21, 1978; U.S. Patent No. 4,299,826 issued to Luedders on November 10, 1981; U.S. Patent No. 4,305,936 issued to Klein on December 15, 1981; U.S. Patent No. 4,309,414 issued to Inagi, Mura atsu & Nagai on January 5, 1982; U.S. Patent No. 4,338,306 issued to Kitao & Nishi ura on July 6, 1982; U.S. Patent No. 4,442,090 issued to Kakeya, Kitao & Nishimura on April 10, 1984; U.S. Patent No. 4,485,033 issued to Kitao & Nishimura on November 27, 1984; U.S. Patent No. 4,537,776 issued to Cooper on August 27, 1985; U.S. Patent No. 4,552,872 issued to Cooper, Loomans & Fawzi on November 12, 1985; U.S. Patent No. 4,557,934 issued to Cooper on December 10, 1985; U.S. Patent No. 4,573,995 issued to Chen, Chun & Enscore on March 4, 1986; U.S. Patent No. 4,626,539 issued to Aungst & DiLuocio on December 2, 1986; U.S. Patent No. 4,637,930 issued to Konno, Kawata, Aruga, Sonobe & Mito i issued January 20, 1987; U.S. Patent No. 4,695,465 issued to Kigasawa, Ohtani, Tanaka & Hayashida on September 22, 1987; European Patent Application No. 0,043,738 of The Procter & Gamble Company in the names of Wickett, Cooper & Loomans, published on June 13 1982; European Patent Application No. 0,095,813 of The Procter & Gamble Company in the name of Cooper, published December 7, 1983; PCT International Patent Application No. W087/03490 of Key Pharmaceuticals, Inc. in the names of Bodor and Loftson, published on June 18, 1987; Washitake, M., T. Anmo, I. Tanaka, T. Arita & M. Nakano, "Percutaneous Absorption of Drugs from Oily Vehicles", Journal o Pharmaceutical Sciences. Vol. 64, No. 3 (March, 1975), pp 397-401; Shahi, V., & J. L. Zatz, "Effect of Formulation Factor on Penetration of Hydrocortisone through Mouse Skin", Journal o Pharmaceutical Sciences. Vol. 67, No. 6 (June, 1978), pp. 789-792 Cooper, E.R., "Increased Skin Permeability for Lipophilic Mole cules", Journal of Pharmaceutical Sciences. Vol. 73, No. (August, 1984), pp. 1153-1156; Aungst, B.J., N. J. Rogers & E. Shefter, "Enhancement of Naloxone Penetration through Human Skin In Vitro Using Fatty Acids, Fatty Alcohols, Surfactants, Sul- foxides and Amides", International Journal of Pharmaceutics. Vol. 33 (1986), pp. 225-234; Green, P.G., & J. Hadgraft, "Facilitated Transfer of Cationic Drugs Across a Lipoidal Membrane by Oleic Acid and Laurie Acid", International Journal of Pharmaceutics. Vol. 37 (JuTy, 1987), pp. 251-255. It is an object of the present invention to provide novel compositions for enhancing the skin penetration of drugs. It is a further object of the present invention to provide such compositions which provide sufficient skin penetration enhancement to achieve therapeutic levels of the drugs in target internal tissues. It is a further object of the present invention to provide such compositions with low dermal irritation, especially in compositions requiring a low pH. It is a still further object of the present invention to provide such compositions having good stability and good cosmetics. SUMMARY OF THE INVENTION The present invention relates to pharmaceutical compositions for topical application having enhanced penetration through the skin comprising: (a) a safe and effective amount of a pharmaceutical active; and (b) from about 0.05% to about 20% of a non-ionic polyacrylamide having a molecular ight of from about 1,000,000 to about 30,000,000. All concentrations and ratios herein are by weight of total composition and all measurements are at 25°C, unless otherwise specified. DETAILED DESCRIPTION OF THE INVENTION The present invention involves compositions comprising certain specific non-ionic polymers which may be applied topically to the skin and which result in improved transdermal penetration of the drugs through the skin. These compositions also have a high solvent tolerance, i.e., high level of solvents such as alcohol and other water-soluble components which may be necessary to solubilize the active can be included in the compositions. Druo Active The compositions of the present invention comprise a safe and effective amount of a drug active. The phrase "safe and effective amount", as used herein, means an amount of a drug high enough to significantly positively modify the condition to be treated, but low enough to avoid serious side effects (at a reasonable benefit/risk ratio), within the scope of sound medical judgement. A safe and effective amount of the drug will vary with the specific drug, the ability of the composition to penetrate the drug through the skin, the amount of composition to be applied, the particular condition being treated, the age and physical condition of the patient being treated, the severity of the condition, the duration of the treatment, the nature of concurrent therapy, and like factors. The drug compounds present in the compositions of the present invention preferably comprise from about 0.1% to about 20% by weight of the compositions, more preferably from aboutθ.1% to about 10%, and most preferably from about 0.1% to about 5%. Mixtures of drug actives may also be used. Useful drug actives in the compositions of the present invention include anti-acne drugs. Anti-acne drugs preferred for use in the present invention include the keratolytics such as salicylcic acid, sulfur, lactic acid, glycolic, pyruvic acid, urea, resorcinol, and N-acetylcysteine; retinoids such as retinoic acid and its derivatives (e.g., cis and trans); antibiotics and antimicrobials such as benzoyl peroxide octopirox, erythromycin, tetracyclin, triclosan, azelaic acid an its derivatives, phenoxy ethanol and phenoxy proponol ethylacetate, clindamycin and meclocycline; sebostats such a flavinoids; hydroxy acids; and bile salts such as scymnol sulfat and its derivatives, deoxycholate, and cholate. Useful drug actives in the compositions of the presen invention include non-steroidal anti-inflammatory drugs (NSAIDS) The NSAIDS can be selected from the following categories: propionic acid derivatives; acetic acid derivatives; fenamic aci derivatives; biphenylcarboxylic acid derivatives; and oxicams. All of these NSAIDS are fully described in the U.S. Patent 4,985,459 to Sunshine et al., issued January 15, 1991, incorporated by reference herein. Most preferred are the propionic NSAIDS including but not limited to aspirin, acetaminophen, ibuprofen, naproxen, benoxaprofen, flurbiprofen, fenoprofen, fenbufen, ketoprofen, indoprofen, pirprofen, carprofen, oxaprozin, pranoprofen, iroprofen, tioxaprofen, suprofen, alminoprofen, tiaprofenic acid, fluprofen and bucloxic acid. Also useful are the steroidal anti-inflammatory drugs including hydrocortisone and the like. Useful drug actives in the compositions of the present invention include antihistaminic drugs. Antihistaminic drugs preferred for inclusion in compositions of the present invention include pharmaceutically-acceptable salts of chlorpheniramine, triprolidine, diphenhydra ine, doxylamine, pyrilamine, phenindamine, pro ethazine, cyproheptadine, azatadine, clemastine, carbinoxamine, tripelennamine, terfenadine, dexchlorpheniramine, brompheniramine, chlorcyclizine, diphenylpyraline, phenira ine and phenyltoloxamine, and mixtures thereof. Useful drug actives in the compositions of the present invention include antitussive drugs. Antitussive drugs preferred for inclusion in compositions of the present invention include pharmaceutically-acceptable salts of dextromethorphan, codeine, caramiphen and carbetapentane. Useful drug actives in the compositions of the presen invention include antipruritic drugs. Antipruritic drug preferred for inclusion in compositions of the present inventio include pharmaceutically-acceptable salts of methdilizine an trimeprazine. Useful drug actives in the compositions of the presen invention include anticholinergic drugs. Anticholinergic drug preferred for inclusion in compositions of the present inventio include phar aceutically-acceptable salts of scopolamine, atropine, homatropine, levodopa, dicyclomine, hyoscyamine, procyclidine, trihexyphenidyl and ethopropazine. Useful drug actives in the compositions of the presen invention include anti-emetic and antinauseant drugs. Anti-emeti and antinauseant drugs preferred for inclusion in compositions o the present invention include pharmaceutically-acceptable salts o cyclizine, meclizine, chlorpro azine, buclizine, metoclopramide, prochlorperazine and trimethobenzamide. Useful drug actives in the compositions of the present invention include anorexic drugs. Anorexic drugs preferred for inclusion in compositions of the present invention include pharmaceutically-acceptable salts of benzpheta ine, phentermine, chlorphentermine, fenfluramine, diethylpropion and phendi etrazine. Useful drug actives in the compositions of the present invention include central stimulant drugs. Central stimulant drugs preferred for inclusion in compositions of the present invention include pharmaceutically-acceptable salts of amphetamine, ethamphetamine, dextroamphetamine and methylphenidate. Useful drug actives in the compositions of the present invention include antiarrhythmic drugs. Antiarrhythmic drugs preferred for inclusion in compositions of the present invention include pharmaceutically-acceptable salts of propranolol, procainamide, disopyramide, quinidine, encainide, flecanaide, mexiletine and tocainide. Other antiarrhythmic drugs preferred for inclusion in compositions of the present invention include pharfflaceutically-acceptable salts of the quinidine derivative disclosed in U.S. Patent No. 4,716,171 issued to Jarreau an Koenig on December 29, 1987, which is hereby incorporated herei in its entirety by reference. Highly preferred compounds include in this class include pharmaceutically-acceptable salts o 3S-hydroxy-10,ll-dihydroquinidine, 3R-hydroxy-10,ll-dihydro- quinidine, 3R-hydroxy-0-acetyl-10,ll-dihydroquinidine, and 3S- hydroxy-0-acetyl-10,ll-dihydroquinidine, especially 3S-hydroxy- 10,11-dihydroquinidine. Useful drug actives in the compositions of the present invention include ø-adrenergic blocker drugs. /3-Adrenergic blocker drugs preferred for inclusion in compositions of the present invention include pharmaceutically-acceptable salts of metoprolol, acebutolol, betaxolol, labetalol and ti olol. ϊ-Adrenergic blocker drugs more preferred for inclusion in compositions of the present invention include metoprolol tartrate, acebutolol hydrochloride, betaxolol hydrochloride, labetalol hydrochloride and timolol aleate. Useful drug actives in the compositions of the present invention include cardiotonic drugs. Cardiotonic drugs preferred for inclusion in compositions of the present invention include pharmaceutically-acceptable salts of milrinone, amrinone and dobutamine. Other cardiotonic drugs preferred for inclusion in compositions of the present invention include pharmaceutically-acceptable salts of 14-amino steroid derivatives, some of which are disclosed in U.S. Patent Nos. 4,325,879, 4,552,868 and 4,584,289, issued to Jarreau and Koenig on April 20, 1982, November 12, 1985 and April 22, 1986, respectively, each of which are hereby incorporated herein in their entirety by reference. Useful drug actives in the compositions of the present invention include antihypertensive drugs. Antihypertensive drugs preferred for inclusion in compositions of the present invention include pharmaceutically-acceptable salts of enalapril, clonidine, hydralazine, minoxidil (which is also a hair growth stimulator drugj, guanadrel, guanethidine, guanfacine, mecamylamin methyldopate, pargyline, phenoxybenzamine and prazosin. Useful drug actives in the compositions of the prese invention include diuretic drugs. Diuretic drugs preferred f inclusion in compositions of the present invention include pharma ceutically-acceptable salts of amiloride and hydrochlorothiazide Diuretic drugs more preferred for inclusion in compositions of th present invention include amiloride hydrochloride. Useful drug actives in the compositions of the presen invention include vasodilator drugs. Vasodilator drugs preferre for inclusion in compositions of the present invention includ pharmaceutically-acceptable salts of diltaze , amiodarone isoxsuprine, nylidrin, tolazoline and verapa il. Useful drug actives in the compositions of the presen invention include vasoconstrictor drugs. Vasoconstrictor drug preferred for inclusion in compositions of the present inventio include pharmaceutically-acceptable salts of dihydroergotamine ergota ine and methysergide. Useful drug actives in the compositions of the presen invention includes anti-ulcer drugs. Anti-ulcer drugs preferre for inclusion in compositions of the present invention includ pharmaceutically-acceptable salts of ranitidine and cimetidine. Useful drug actives in the compositions of the presen invention include include anesthetic drugs. Anesthetic drug preferred for inclusion in compositions of the present inventio include pharmaceutically-acceptable salts of lidocaine bupivacaine, chlorprocaine, dibucaine, etidocaine, mepivacaine, tetracaine, dyclonine, hexylcaine, procaine, cocaine, keta ine, pramoxine and phenol. Useful drug actives in the compositions of the presen invention include antidepressant drugs. Antidepressant drug preferred for inclusion in compositions of the present inventio include pharmaceutically-acceptable salts of imipramine, desipramine, amitriptyline, nortriptyline, protriptyline, doxepin, maprotiline, phenelzine, tranylcypromine, trazodone an trimipra ine. Useful drug actives in the compositions of the presen invention include tranquilizer and sedative drugs. Tranquilize and sedative drugs preferred for inclusion in compositions of th present invention include pharmaceutically-acceptable salts o chlordiazepoxide, benactyzine, benzquinamide, flurazepam, hydroxyzine, loxapine and promazine. Useful drug actives in the compositions of the present invention include antipsychotic drugs. Antipsychotic drugs preferred for inclusion in compositions of the present invention include pharmaceutically-acceptable salts of chlorprothixene, fluphenazine, haloperidol, olindone, thioridazine and trifluoperazine. Useful drug actives in the compositions of the present invention include antimicrobial drugs (antibacterial, antifungal, antiprotozoal and antiviral drugs). Antimicrobial drugs preferred for inclusion in compositions of the present invention include pharmaceutically-acceptable salts of 0-lactam drugs, quinolone drugs, ciprofloxacin, norfloxacin, tetracycline, erythromycin, amikacin, triclosan, doxycycline, capreomycin, chlorhexidine, chlortetracycline, oxytetracycline, clindamycin, ethambutol, metronidazole, pentamidine, genta icin, kana ycin, lineomycin, methacycline, methena ine, minocycline, neomycin, netilmicin, paromomycin, streptomycin, tobra ycin, iconazole and amanfadine. Antimicrobial drugs preferred for inclusion in compositions of the present invention include tetracycline hydrochloride, erythromycin estolate, erythromycin stearate (salt), amikacin sulfate, doxycycline hydrochloride, capreomycin sulfate, chlorhexidine gluconate, chlorhexidine hydrochloride, chlortetracycline hydro¬ chloride, oxytetracycline hydrochloride, clindamycin hydro- chloride, ethambutol hydrochloride, metronidazole hydrochloride, pentamidine hydrochloride, gentamicin sulfate, kanamycin sulfate, lineomycin hydrochloride, methacycline hydrochloride, methenamine hippurate, methenamine andelate, .minocycline hydrochloride, neomycin sulfate, netilmicin sulfate, paromomycin sulfate, streptomycin sulfate, tobramycin sulfate, miconazole hydrochloride, amanfadine hydrochloride, amanfadine sulfate, triclosan, octopirox, parachlorometa xylenol, nystatin, tolnaftat and clotrimazole. Useful drug actives in the compositions of the presen invention include antineoplastic drugs. Antineoplastic drug preferred for inclusion in compositions of the present inventio include pharmaceutically-acceptable salts of bleomycin daunorubicin, doxorubicin, mechlorethamine, procarbazine quinacrine, ta oxifen, vinblastine and vincristine. Useful drug actives in the compositions of the presen invention include antimalarial drugs. Antimalarial drug preferred for inclusion in compositions of the present inventio include pharmaceutically-acceptable salts of chloroquine hydroxychloroquine primaquine and quinine. Useful drug actives in the compositions of the presen invention include muscle relaxant drugs. Muscle relaxant drug preferred for inclusion in compositions of the present inventio include pharmaceutically-acceptable salts of cinnamedrine, cyclobenzaprine, flavoxate, orphenadrine, papaverine, mebeverine, idaverine, ritodrine, dephenox late, dantrolene and azumolene. Useful drug actives in the compositions of the present invention include antispas odic drugs. Antispasmodic drugs preferred for inclusion in compositions of the present invention include pharmaceutically-acceptable salts of the compounds disclosed in U.S. Patent Number 3,856,825 issued to Wright, Burch and Goldenburg on December 24, 1974, which is hereby incorporated herein in its entirety by reference. Useful drug actives in the compositions of the present invention include antidiarrheal drugs. Antidiarrheal drugs preferred for inclusion in compositions of the present invention include pharmaceutically-acceptable salts of loperamide. Useful drug actives in the compositions of the present invention include bone-active drugs. Bone-active drugs preferred for inclusion in compositions of the present invention include pharmaceutically-acceptable salts of diphosphonate drug compounds and phosphonoalkylphosphinate drug compounds, including the prodrug esters thereof. Such compounds are disclosed, for example, in U.S. Patent Nos.3,683,080 issued to Francis on Augu 8, 1972; 4,304,734 issued to Jary, Rihakova & Zobacova on Decemb 8, 1981; 4,687,768 issued to Benedict & Johnson on August 1 1987; 4,711,880 issued to Stahl & Schmitz on December 8, 1987; a 4,719,203 issued to Bosies & Gall on January 12, 1988; copendi U.S. patent application Serial Nos. 808,584, of Benedict & Perkin filed December 13, 1985; 945,069 of Ebetino, Buckingham & McOske filed December 19, 1986; 945,068*of Ebetino & Benedict file December 19, 1986; and 069,666 of Ebetino filed July 6, 1987; an European Patent Application Nos. 0,001,584 of Blum, Hempel Worms, published May 2, 1979; 0,039,033 published April 11, 1981 0486,405 of Benedict & Perkins, published July 2, 1986; an 0,243,173 of Oku, Todo, Kasahara, Nakamura, Kayakiri & Hashimoto published October 28, 1987; all of which are hereby incorporate herein in their entirety by reference. Also useful in the present invention are sunless tannin agents including di ydroxyacetone, indole derivatives, and th like. These sunless tanning agents may also be used i combination with conventional sunscreen agents such as thos disclosed in Segarin, et al., at Chapter VIII, pages 189 et seq., of Cosmetics Science and Technology, incorporated by reference herein, as well as wound healing agents such as peptide derivatives, yeast, panthenol, lamin and kinetin. Other usefulskin actives include skin bleaching (or lightening) agents including but not limited to hydroquinone, ascorbic acid, kojic acid and sodium metabisulfite. Nonionic Polyacrylamide The non-ionic polymers useful in the present invention are polyaery1amides and substituted polyacrylamides, branched or unbranched. These polymers are non-ionic water-dispersable polymers which can be formed from a variety of monomers including acrylamide and methacrylamide which are unsubstituted or substituted with one or two alkyl groups (preferably C1-C5). Preferred acrylate amides and methacrylate amides in which the amide nitrogen is unsubstituted, or substituted with one or two C1-C5 alkyl groups (preferably: methyl, ethyl or propyl), for example, acrylamide, methacrylamide, (*See page 19 for equivalents.) N-methylacrylamide, N-methylmethacrylamid N,N-dimethyl ethacrylamide, N-isopropylacrylamid N-isopropylmethacrylamide and N,N-dimethylacrylamide. The monomers are generally disclosed in U. S. Patent 4,963,348 t Bolich, Jr. et al., issued October 16, 1990, incorporated b reference herein in its entirety. These copolymers may optionall be formed using conventional neutral crosslinking agents such a dialkenyl compounds. The use of such crosslinking agents fo cationic polymers is disclosed in U.S. Patent 4,628,078 to Glove et al. issued December 9, 1986 and U.S. Patent 4,599,379 t Flesher et al. issued July 8, 1986 both of which are incorporate by reference herein. These non-ionic co-polymers have a molecula weight greater than about 1,000,000 preferably greater than abou 1,500,000 and range up to about 30,000,000. Preferably, as result of being synthesized by reverse phase emulsio polymerization, these non-ionic polyacrylamides are predisperse in a water-immiscible solvent such as mineral oil and the like containing a high HLB surfactant (HLB from about 7 to about 10 which helps to facilitate water dispersibility of th polyacrylamide. Most preferred for use herein is the non-ioni polymer under the CTFA designation: polyacrylamide and isoparrafi and laureth-7, available as Sepigel from Seppic Corporation. These non-ionic polyacrylamides are present at a level fro about 0.05% to about 20%, preferably from about 0.05% to 5% an most preferably from about 0.1% to about 10%. Vehicle The compositions of the present invention are use along with pharmaceutically-acceptable carrier (or vehicle components. The term "pharmaceutically-acceptable carrie components", as used herein, means compatible solid or liqui filler diluents which are suitable for administration to a huma or lower animal. The term "compatible", as used herein, mean that the components are capable of being commingled with the dru compounds, diols and fatty acids of the compositions of th present invention, and with each other, in a manner such tha there is no interaction which would substantially reduce th pharmaceutical efficacy of the compositions of the presen invention under ordinary use situations. Pharmaceutically-acceptable carrier components must, of course, be of sufficiently high purity and sufficiently low toxicity to render them suitable for administration to the human or lower animal being treated. Some examples of substances which can serve as pharmaceuti¬ cally-acceptable carrier components are polyethylene glycol; glycerol; ethanol; water; antioxidants; surfactants; chelating agents; preservatives; thickeners; as well as other non-toxic com- patible substances used in pharmaceutical formulations. These compositions can also contain one or more humectants/moisturizers many of which may also be useful as pharmaceutical actives. A variety of humectants/moisturizers can be employed and can be present at a level of from about 1% to about 30%, more preferably from about 2% to about 8% and most preferably from about 3% to about 5%. These materials include polyhydroxy alcohols such as sorbitol, glycerin, hexanetriol, propylene glycol, hexylene glycoT and the like; polyethylene glycol; sugars and starches; sugar and starch derivatives (e.g. alkoxylated glucose); D-panthenol; hyaluronic acid; lactamide monoethanolamine; acetamide monoethanola ine; and mixtures thereof. Preferred humectants/moisturizers for use in the compositions of the present invention are the C3-C6 diols and triols. Especially preferred is the triol, glycerin. The compositions of this invention may also contain pharmaceutically acceptable optional components that modify the physical and/or therapeutic effects of the compositions. Such optional components may include, for example, additional solvents, emulsifiers, gelling agents, fragrances, preservatives, and stabilizers. However, such optional materials must not unduly interfere with the transdermal delivery of the drug active. Optional components useful in the compositions of this invention are described in the following patent documents, incorporated by reference herein: European Patent Publication 43,738, Wickett et al., published January 13, 1982; and U.S. Patent 4,552,872, Cooper et al., issued Novem 12, 1985. Most preferred compositions herein are gel-type composition Another optional material is a solvent or co-solve material. Such solvent materials include, for example, sho chain alcohols and ethers. Preferred optional solvent materia include polyethylene glycols, dipropylene glycol, ethylene glyc monoethyl ether, ethanol, isopropanol, and dimethyl isosorbid Water may also be used as a solvent or co-solvent in t compositions of this invention. If water is used in a saturat system, a gel or emulsion is preferably formed. Most preferred compositions have a pH of below about preferably below about 4, and most preferably below about 3. While particular embodiments of the present invention ha been described, it will be obvious to those skilled in the a that various changes and modifications to the compositions di closed herein can be made without departing from the spirit a the scope of the invention. It is intended to cover, in t appended claims, all such modifications that are within the sco of this invention. Test Method Transdermal penetration of drugs is conveniently determin and compared from various vehicles using the apparatus a procedure described below. Full thickness excised human thigh skin is obtained fr cadavers after all hair had been clipped and the skin washed. T skin samples are then bathed in 10% glycerin and stored frozen The glycerin prevents the formation of ice crystals which coul possibly damage the keratinized cells and/or the intercellula lipid matrix. After a rapid thawing, the skin is conditioned fo 24 hours in Hank's Balanced Salt Solution with 1 antibacterial-antimycotic solution. Then the skin is washed wit distilled water. A single skin donor is used for each experiment and individual sections for use are selected based on integrity o the stratum corneum (visual determination). Selected areas ar cut to 1cm 2 using a scalpel. Tests are conducted using glass diffusion cells placed in temperature-regulated stirring modules. Skin sections are mounted in the cells, and the receptor phase is added. The receptor phase is 50% Hank's Balance Salt Solution with 1% antibiotic-antimycotic solution. Each diffusion cell has an exposed area of 0.79cm2 and a receptor capacity of 5ml. Sufficient formulation is applied (750ul) to the surface of the skin to ensure infinite dose conditions, and the diffusion cell is covered with plastic wrap or parafilm to prevent product evaporation. At each sampling time the receptor phase is removed for analysis of drug content. The receptor phase is removed for analysis of drug content. The receptor phase is replenished at each sampling time in order to maintain sink conditions. Preferably 3 to 6 replicates are run with sampling intervals occurring at 1, 2, 4 & 6 hours. Penetration rate (Flux) is determined as the quantity of drug penetrating a measured area of skin per hour during the 5 hour interval between 1 hour and 6 hours. Generally steady state is reached before 1 hour. Penetration rate is usually expressed as ug drug per cm2 skin per hour. The following examples further describe and demonstrate embodiments within the scope of the present invention. The examples are given solely for the purpose of illustration and are not to be construed as limitations of the present invention, as many variations thereof are possible without departing from the spirit and scope of the invention. Ingredients are identified by chemical or CTFA name. EXAMPLES Example I An anti-acne composition is made by combining the followin ingredients. Ingredient (%W/Wι Water, Purified 52.395 Alcohol SDA 40 40.000 Polyacrylamide and Ci3-i Isoparaffin and Laureth-7 4.000 Salicylic Acid 2.000 Glycerin 1.000 Aloe Vera Gel 0.500 Menthol 0.100 Disodium EDTA 0.005 The alcohol is added to a suitable size container. Using Lightnin' mixer with a 3 blade paddle prop, the salicylic acid is added to the alcohol and mixed at low speed (100 rpm) until the salicylic acid is dissolved. Menthol is added to the alcohol and mixed until dissolved. Separately, water is added to a suitable size container. Aloe vera gel and disodium EDTA are added to the water and mixed at low speed (100 rpm) until completely dissolved. The water phase is then added to the alcohol phase and mixed until clear. Gylcerin is added and mixed until clear. While mixing at moderate speed (300 rpm), the polyacrylamide and C13-1 isoparaffin and laureth-7 is added to form a gel. The resulting gel is mixed at moderate speed until uniform. Example II An anti-acne and/or analgesic composition is made by combining the following ingredients utilizing conventional mixing techniques as described above in Example I. Inαredient (%W/W) Water, Purified 55.0 Ibuprofen 2.0 Alcohol SDA 40 40.0 Polyacrylamide and C13-14 Isoparaffin and Laureth-7 3.0 The compositions display skin penetration of the Ibuprofen active as well as improved skin feel and residue characteristics together with excellent moisturizing, emolliency, rub-in and absorption characteristics. Example HI A keratolytic composition for dermatological disorders is made by combining the following ingredients utilizing conventional mixing techniques as described above in Example I. Ingredient ι%W/W) Water 86.5 Urea 10.0 Benzyl Alcohol 0.5 Polyacrylamide and c 13-14 Isoparaffin and Laureth-7 3.0 The compositions display skin penetration of the Urea active as well as improved skin feel and residue characteristics together with excellent moisturizing, emolliency, rub-in and absorption characteristics. Example IV A composition for sunless tanning is made by combining the following ingredients utilizing conventional mixing techniques as described above in Example I. Ingredient (%W/W) Water 91.5 Benzyl Alcohol 0.5 Polyacrylamide and 5 Ci3-i4 Isoparaffin and Laureth-7 3.0 Dihydroxyacetyone 3.0 Glycerin 2.0 The compositions display improved skin penetration of 10 dihydroxyacetone as well as improved skin feel and residue ch teristics together with excellent moisturizing, emolliency, r and absorption characteristics. (♦Equivalents: USSN 808584 equivalent to US Patent 4,902,679; USSN 945069 equivalent to US Patent 4,868,164; USSN 945068 15 equivalent to EP Patent 0,274,158; and USSN 069666 equivalent EP Δppln. 298,553.)

Claims: CLAIMS: 1. A topical pharmaceutical composition having enhanced penetration through the skin comprising: (a) a safe and effective amount of a pharmaceutical active; and (b) from 0.05% to 5% of a non-ionic polyacrylamide having a molecular wight of from 1,000,000 to 30,000,000. 2. The composition of Claim 1 wherein the polyacrylamide comprises monomers selected from acrylamide and methacrylamide which are unsubstituted or substituted with at least one alkyl group having from 1 to 5 carbon atoms, preferably wherein the polyacrylamide comprises monomers selected from the group consisting of acrylamide, methacrylamide, N-methylacrylamide, N-methyl ethacrylamide, N,N-dimethylmethacrylamide, N-isopropylacrylamide, N-isopropylmethacrylamide and N,N-dimethylacrylamide, and more preferably wherein the polyacrylamide has a molecular weight greater than 1,500,000. 3. The composition of Claim 2 wherein said pharmaceutical active is selected from the group consisting of ant-acne drugs, non-steroidal anti-inflammatory drugs, steroidal ant -inflammatory drugs, sunless tanning agents, sunscreen agents, wound healing agents, skin bleaching or lightening agents, antihistaminic drugs, antitussive drugs, antipruritic drugs, anticholinergic drugs, anti-emetic and antinauseant drugs, anorexic drugs, central stimulant drugs, antiarrhythmic drugs,^-adrenergic blocker drugs, cardiotonic drugs, anti ypertensive drugs, diuretic drugs, vasodilator drugs, vasoconstrictor drugs, anti-ulcer drugs, anesthetic drugs, antidepressant drugs, tranquilizer and sedative drugs, antipsychotic drugs, antimicrobial drugs, antineoplastic drugs, antimalarial drugs, muscle relaxant drugs, antispasmodic drugs, antidiarrheal drugs and bone-active drugs and mixtures thereof. 4. The composition of Claim 5 herein said pharmaceutical active is an acne active selected from the group consisting of salicylcic acid, sulfur, resorcinol, N-acetylcysteine, octopirox, retinoic acid and its derivatives, benzoyl peroxide, erythromycin, tetracyclin, azelaic acid and its derivatives, phenoxy ethanol and phenoxy proponol, ethylacetate, clindamycin and meclocycline, flavinoids, lactic acid, glycolic acid, pyruvic acid, urea, scymnol sulfate and its derivatives, deoxycholate and cholate and mixtures thereof. 5. The composition of Claim 3 wherein said antihistaminic drug is selected from the group consisting of chlorpheniramine maleate, chlorpheniramine tannate, triprolidine hydrochloride, triprolidine oxalate, diphenhydra ine hydrochloride, diphen- hydramine ascorbate, diphenhydramine citrate, doxylamine suc- cinate, pyrilamine maleate, pyrilamine hydrochloride, pyrilamine tannate, phenindamine tartrate, pro ethazine hydrochloride, cyproheptadine hydrochloride, azatadine maleate, clemastine fumarate, carbinoxa ine maleate, carbinoxamine hydrochloride, tripelennamine hydrochloride, tripelennamine citrate, dexchlorpheniramine maleate, brom- phenira ine maleate and chlorcyclizine hydrochloride and mixtures thereof; wherein said antitussive drug is selected from the group consisting of dextromethorphan hydrobromide, carbetapentane citrate, codeine phosphate and codeine N-oxide hydrochloride and mixtures thereof; wherein said anticholinergic drug is selected from the group consisting of scopolamine hydrobromide, scopolamine hydrochloride, atropine sulfate, atropine mucate, homatropine hydrobromide and homatropine hydrochloride and mixtures thereof; wherein said anti-emetic or antinauseant drug is selected from the group consisting of cyclizine hydrochloride, meclizine hydrochloride, chlorpromazine hydrochloride and chlorpromazine maleate and mixtures thereof; wherein said anorexic drug is selected from the group consisting of benzpheta ine hydrochloride, phentermine hydrochloride, chlorphentermine hydrochloride and fenfluramine hydrochloride and mixtures thereof; wherein said antimicrobial drug is selected from the group consisting of^-lacta drugs, quinolone drugs, c profloxacin, norfloxacin, tetracycline, erythromycin, amikacin, triclosan, doxycycline, capreomycin, chlorhexidine, chlortetracycline, oxytetracycline, clindamycin, ethambutol, metronidazole, pentamidine, gentamicin, kanamycin, lineomycin, methacycline, methenamine, minocycline, neomycin, netilmicin, paromomycin, streptomycin, tobramycin, miconazole and amanfadine, pharmaceutically-acceptable salts thereof and mixtures thereof; wherein said antiarrhythmic drug is selected from the group consisting of propranolol hydrochloride, procaina ide hydrochloride, quinidine sulfate and quinidine gluconate and mixtures thereof; wherein said antihypertensive drug is selected from the group consisting of enalapril maleate, clonidine hydrochloride, hydralazine hydrochloride and hydralazine sulfate and mixtures thereof; wherein said anesthetic or antipruritic drug is selected from the group consisting of lidocaine hydrochloride, bupivacaine hydro¬ chloride, chlorprocaine hydrochloride, dibucaine hydrochloride, etidocaine hydrochloride, mepivacaine hydro¬ chloride, tetracaine hydrochloride, dyclonine hydrochloride and hexylcaine hydrochloride and mixtures thereof; wherein said bone-active drug is selected from the group consisting of 6-amino-l-hydroxy-hexane-l,l-diphosphonic acid, 3-amino-l-hydroxy-propane-l,l-diphosphonic acid, octahydro-l-pyridine-6,6-diphosphonic acid, 2-(2'-piperi¬ dinyl)-ethane-l,l-diphosphonic acid; 2-(3'-piperi- dinyl)-ethane-l,l-diphosphonic acid; 2-(2'-piperidinyl)-l- hydroxy-ethane-l,l-diphosphonic acid; 2-(3'-piperidiny7)-l- hydroxy-ethane-l,l-diphosphonic acid; N-(2'-(3'-methyl)-piperidinylidene)-amino-methane diphosphonic acid; N-(2'-( ,3 Λ -diazinylidene))-aminomethane diphosphonic acid; and N-(2-(3-methylpiperidinylidene))-aminomethane- phosphonomethylphosphinic acid, or esters thereof and mixtures thereof; and wherein said non-steroidal anti-inflammatory drug is selected from the group consisting of propionic acid derivatives, acetic acid derivatives, fenamic acid derivatives, biphenylcarboxylic acid derivatives, and oxicams and mixtures thereof; preferably wherein said non-steroidal anti-inflammatory drug is a propionic acid derivatives selected from the group consisting of aspirin, acetaminophen, ibuprofen, naproxen, benoxaprofen, flurbiprofen, fenoprofen, fenbufen, ketoprofen, indoprofen, pirprofen, carprofen, oxaprozin, pranoprofen, miroprofen, tioxaprofen, suprofen, alminoprofen, tiaprofenic acid, fluprofen and bucloxic acid and mixtures thereof. 6. The composition of Claim 3 wherein said drug active is a sunless tanning agent selected from the group consisting of dihydroxyacetone, indole derivatives and mixtures thereof. 7. The composition of Claim 6 which further comprises a sunscreen active.

Inventors: DECKNER GEORGE ENDEL, LOMBARDO BRIAN SCOTT, DECKNER, GEORGE, ENDEL, LOMBARDO, BRIAN, SCOTT
Applicants: RICHARDSON VICKS INC, RICHARDSON-VICKS, INC.
Application year: 1992
Main classification: A61K47
IPC codes: A61K8, A61K9, A61K47, A61Q19