NEW PHARMACEUTICAL FORMULATIONS WITH PROGRAMMED RELEASE CONTAINING ANTIPHLOGISTICS

Abstract: New galenic formulations with programmed release, to be administered by oral route, containing as the active ingredient a compound endowed with antiphlogistic, analgesic and antipyretic activity like, for instance, an arylacetic or an arylpropionic acid and the pharmaceutical­ ly acceptable salts thereof. In these new formulations, a portion of the active ingredient is released in a short time, so that the drug can quickly develop its therapeutic action reaching the necessary hematic levels, while the remaining portion of the active constituent is released in a longer interval of time so as to allow the therapeutic coverage till the subsequent administration. Said therapeutic coverage can even last 24 hours; thus the new galenic formulations object of the present invention are suitable for a once a day administration.

Description: New pharmaceutical formulations with programmed release, to be administered by oral route, containing as the active ingredient a compound endowed with antiphlogistic, analgesic and antipyretic activity like, for instance, an arylacetic or an arylpropionic acid and the pharmaceutically acceptable salts thereof. In these new formulations, a portion of the active ingredient is released in a short time, so that the drug can quickly develop its therapeutic action reaching the necessary hematic levels, while the remaining portion of the active constituent is released in a longer interval of time so as to allow the therapeutic coverage till the subsequent administration. Said therapeutic coverage can even last 24 hours; thus the new galenic formulations object of the present invention are suitable for a once a day administration. The art skilled man knows well the problems connected with the repeated administrations of drugs. Apart from the trouble and the discomfort, mostly psychologic, which the patient can experience when he has to recollect of taking that determinate medicine three or four times a day (as it happens, for instance, with paracetamol), it must be borne in mind that, from the point of view of the absorption kinetics, a repeated administration is responsible of very high hematic levels of the drug which repeatedly occur in the organism of the patient, with a remarkable increase in the possibility of side effects. In the literature many methodologies are described, generically called "retard", by means of which the number of administrations of a drug can be reduced while keeping unaltered its therapeutic effectiveness along the time. Thus, for instance, slow-release tablets of indomethacin, where the active principle is coated by a film of a hydrophilous polymer and by a cellulose ether, are claimed in JP-A-58170712, while in JP-A-59084821, diclofenac, which is another well known antiphlogistic agent, is mixed with β-cyclodestrin. In DE-OS 3001797, indoprofen, a good analgesic and antiinflammatory agent which has the drawback of having a short plasmatic half-life, is microencapsulated in a protective layer of a cellulose ether, thus obtaining a remarkable improvement of its plasmatic half-life. Finally, in EP-A-0094116, EP-A-0094117 and EP-A-0094123, granules are described which have a double coating, the first are made by polyvinylpyrrolidone and the second one made by acrilic polymers or by cellulose esters or by fatty or oily substances, which should allow a better release of antiphlogistic drugs either in the stomach and in the gut. JP-A-79129115 discloses formulations of amoxycillin which are prepared from a mixture of slow-release and fast-release granules containing lactose and starch and whereby the intestinal solubility or insolubility respectively are obtained through the granulation with a solution of gum arabic or of cellulose acetate phthalate. In all of these pharmaceutical formulations, however, the initial release of the active ingredient is gradual and slow, so that the therapeutic effect begins only some hours after the administration. This is an evident drawback, especially in case of drugs which contemporaneously present antiinflammatory, analgesic and antipyretic activity, where often a quick release is needed in order to obtain a prompt analgesic effect, besides the slow and regular release in order to cure the inflammation. New pharmaceutical formulations with programmed release immediate and delayed, are the object of the present invention. These formulations are administrable by oral route and contain, as the active principle, an antiinflammatory, analgesic and antipyretic drug such as, for instance, an arylacetic or arylpropionic acid, both as the free acid and as the corresponding pharmaceutically acceptable salt with organic or inorganic bases. In order to remove the drawbacks of the known controlled release formulations, and in order to obtain an adequate therapeutic response since the beginning, the galenic formulations object of the present invention are made by a mixture of a granulate having an immediate release with a granulate having a controlled release, in terms of active ingredient. In this way, by suitably selecting both the kind and the amount of the agents to be used in the manufacture of the two granulates, and the weight ratio between the two types of granulate, it is possible to obtain pharmaceutical formulations having an immediate therapeutic activity which protracts along 12-24 hours, being therefore suitable for a once a day administration. We have found that the better therapeutic result is obtained when, in the pharmaceutical formulations described in the present invention, the active principle is contained in amounts comprised from 30% to 70% in weight of the whole weight of the active principle itself both in the immediate release granulate and in the controlled release granulate. The arylacetic and arylpropionic acids which can advantageously be used for the purposes of the present invention comprise, among the others, internationally known antiinflammatories like naproxen, ibuprofen, indoprofen, ketoprofen, flurbiprofen, diclofenac, indomethacin, fenoprofen, fentiazac and analogs. A preferred aspect of the present invention comprises pharmaceutical formulations as above described wherein the active constituent is an antiinflammatory agent selected among diclofenac, ibuprofen, naproxen and ketoprofen. Tablets, capsules, sugar coated tablets and granulates for suspension or for solution in suitable liquid media are the preferred pharmaceutical formulations. In the preparation of the pharmaceutical formulations object of the present invention, the immediate release granulate is prepared by dry granulating the active principle with suitable adjuvant agents like binding, disintegrating and lubricating agents and then sifting the granules on a sieve having meshes of 1 mm. Polyvinylpyrrolidone, carboxymethylcellulose, micro-crystalline cellulose, lactose, saccharose, mannitol, gum-arabic, pectin and gelatin can be advantageously used as binding agents. Starch, sodium starch glycolate, alginates and reticutaled polyvinylpyrrolidone can be used as disintegrating agents. Talc, magnesium stearate, stearlc acid and silica gel can be used as lubricating agents. Polyvinylpyrrolidone, lactose, maize starch, sodium starch glycolate and magnesium stearate are the preferred adjuvants in the fulfillment of the present invention. The granulate having a controlled release, in its turn, is prepared by wet granulating the active principle together with the retarding agents by means of a solvent selected among an alcohol containing from 1 to 4 carbon atoms, an aromatic hydrocarbon, a ketone containing from 3 to 6 carbon atoms, an alkyl halide containing from 1 to 4 carbon atoms, mixtures thereof or mixtures thereof with water, then drying the granules in oven at 50°C and sifting them through a sieve having meshes of 1 mm. Alcohols containing from 1 to 4 carbon atoms and their mixtures with water are the preferred solvents, mostly 95% ethyl alcohol. Many retarding agents can be advantageously used; they are preferably selected among ethylcellulose, methylcellulose, polyvinylacetate, methacrylic acid esters, cellulose acetate, fatty alcohols containing from 12 to 32 carbon atoms, glyceric esters of fatty acids containing from 10 to 22 carbon atoms, like the mono- and di-stearate of glycerine, esters of fatty acids and alcohols having from 12 to 31 carbon atoms, paraffin, natural waxy substances like beeswax, unbleached wax, candelilla wax, carnauba wax, sealing wax, spermaceti, ozokerite and hydrogenated vegetable oils like hydrogenated castor oil, hydrogenated peanut oil, hydrogenated cotton seed oil and mixtures thereof. Methylcellulose, ethylcellulose, hydrogenated vegetable oils and mixtures thereof are the retarding agents preferred in the fulfillment of the present invention. The two granulates are mixed in such weight ratios that the active principle contained in the final pharmaceutical formulation belongs to each one of the two granulates for a percent comprised between 30% and 70% of the whole active principle. The granulate having immediate release, contains from 60% to 70% of active principle, from 20% to 30% of binding agents, from 8% to 12% of disintegrating agents and from 0.2% to 1% of a lubricating agent. The granulate having controlled release contains from 60% to 70% of active principle and from 30% to 40% of a retarding agent or of a mixture of retarding agents. In a preferred, but not limiting, aspect of the invention, where naproxen is the antiphlogistic drug used as active principle, the composition of the granulates is as follows: a) Granulate having immediate release : from 60% to 70% of naproxen, from 17% to 23% of lactose, from 3% to 7% of polyvinylpyrrolidone, from 4% to 8% of maize starch, from 3% to 6% of sodium starch glycolate, from 0.2% to 0.5% of magnesium stearate. b) Granulate having controlled release : from 60% to 70% of naproxen, from 20% to 30% of hydrogenated castor oil, from 6% to 12% of ethylcellulose. The two granulates are mixed in such weight ratios that the percents of naproxen present in the two granulates of the final pharmaceutical formulation are comprised between 30% and 70% of the whole amount of naproxen present in the formulation itself. Some examples of pharmaceutical formulations obtained according to that previously said are hereunder reported in order to illustrate that invention; nevertheless such examples are not to be interpreted as a limitation of the invention itself. Pharmacokinetic tests have been carried out in man in order to verify the effectiveness both immediate and in the long time of the above described pharmaceutical formulations. These pharmacokinetic tests have been carried out on groups each made of six healthy volunteers, by examining the hematic levels of naproxen 2, 3, 4, 6, 8, 10, 12, 24 and 36 hours after the administration of the pharmaceutical formulations. The values reported in the following table 1 are calculated over the mean of the values of the single values of the six healthy volunteers; the naproxen has been checked in the plasma by spectrophotometric route at 272 nm after crossing through a column for liquid chromatography under high pressure (HPLC) by using a LC 601 Perkin-Elmer apparatus; the values are expressed in mcg/ml of plasma. Hematic levels of naproxen expressed in mcg/ml of human plasma Times of drawing hours Example 1 (mcg/ml) Example 2 (mcg/ml) Example 3 (mcg/ml) Example 4 (mcg/ml) 2 35.7 43.9 57.0 39.4 3 42.8 48.3 52.2 41.1 4 44.3 45.7 48.6 40.8 6 50.1 54.8 57.8 46.5 8 48.4 47.9 51.8 40.9 10 49.6 45.3 46.9 38.1 12 52.8 34.5 39.8 34.3 24 38.1 20.6 26.2 17.1 32 30.9 15.8 19.0 13.7

Claims: Claims for the following Contracting States : BE, CH, DE, FR, GB, IT, LI, LU, NL, SE Pharmaceutical formulation for oral use with programmed release containing as the active principle a compound endowed with antiinflammatory, analgesic and antipyretic activity, formed by a mixture of a granulate having immediate release containing from 30% to 70% of the whole amount of the active principle In admixture with binding, disintegrating and lubricating agents, and of a granulate having controlled release containing from 30% to 70% of the whole amount of the active principle in admixture with retarding agents selected from ethylcellulose, methylcellulose, polyvinylacetate, methacrylic acid esters, cellulose acetate, fatty alcohols containing from 12 to 32 carbon atoms, glyceric esters of fatty acids containing from 10 to 22 carbon atoms, esters of fatty acids and alcohols having from 12 to 31 carbon atoms, paraffin, beeswax, unbleached wax, candelilla wax, carnauba wax, sealing wax, spermaceti, ozokerite, hydrogenated vegetable oils and mixtures thereof. Pharmaceutical formulations according to claim 1, characterized in that the active principles having antiinflammatory, analgesic and antipyretic activity are arylacetic and arylpropionic acids both as free acids and as pharmaceutically acceptable salts with organic or inorganic bases. Pharmaceutical formulations according to claim 2, characterized in that the active principles having antiinflammatory, analgesic and antipyretic activity are selected from naproxen, ibuprofen, flurbiprofen, ketoprofen, fenoprofen, indomethacin, diclofenac and fentiazac. Pharmaceutical formulations according to claim 3 wherein the active principles having antiinflammatory, analgesic and antipyretic activity are selected from naproxen, ibuprofen, ketoprofen and diclofenac. Pharmaceutical formulations according to claim 1 wherein the binding agents are selected from polyvinylpyrrolidone, carboxymethylcellulose, microcrystalline cellulose, lactose, saccharose, mannitol, arabic gum, pectin and gelatin, the disintegrating agents are selected from starchs, alginates, sodium starch glycolate and reticulated polyvinylpyrrolidone, the lubricating agents are selected from magnesium stearate, talc, stearic acid and silica gel. Pharmaceutical formulations according to claim 1 wherein the retarding agents are selected from methylcellulose, ethylcellulose, hydrogenated castor oil, hydrogenated peanut oil, hydrogenated cotton seed oil and mixtures thereof. Pharmaceutical formulations according to claim 1 wherein the granulate having immediate release contains from 60% to 70% of the active principle, from 20% to 30% of binding agents, from 8% to 12% of disintegrating agents and from 0.2% to 1% of lubricating agents. Pharmaceutical formulations according to claim 1 wherein the granulate having controlled release contains from 60% to 70% of the active principle and from 30% to 40% of a retarding agent selected from ethylcellulose, methylcellulose, polyvinylacetate, methacrylic acid esters, cellulose acetate, fatty alcohols containing from 12 to 32 carbon atoms, glyceric esters of fatty acids containing from 10 to 22 carbon atoms, esters of fatty acids and alcohols having from 12 to 31 carbon atoms, paraffin, beeswax, unbleached wax, candelilla wax,carnauba wax, sealing wax, spermaceti, ozokerite, hydrogenated vegetable oils and mixtures thereof. Pharmaceutical formulations according to claim 8 wherein the retarding agents are defined as in claim 6. Claims for the following Contracting States : AT, ES, GR Process for the production of a pharmaceutical formulation for oral use with programmed release containing as the active principle a compound endowed with antiinflammatory, analgesic and antipyretic activity, characterized by mixing a granulate having immediate release containing from 30% to 70% of the whole amount of the active principle in admixture with binding, disintegrating and lubricating agents, and a granulate having controlled release containing from 30% to 70% of the whole amount of the active principle in admixture with retarding agents selected from ethylcellulose, methylcellulose, polyvinylacetate, methacrylic acid esters, cellulose acetate, fatty alcohols containing from 12 to 32 carbon atoms, glyceric esters of fatty acids containing from 10 to 22 carbon atoms, esters of fatty acids and alcohols having from 12 to 31 carbon atoms, paraffin, beeswax, unbleached wax, candelilla wax, carnauba wax, sealing wax, spermaceti, ozokerite, hydrogenated vegetable oils and mixtures thereof. Process according to claim 1, characterized in that the active principles having antiinflammatory, analgesic and antipyretic activity are arylacetic and arylpropionic acids both as free acids and as pharmaceutically acceptable salts with organic or inorganic bases. Process according to claim 2, characterized in that the active principles having antiinflammatory, analgesic and antipyretic activity are selected from naproxen, ibuprofen, flurbiprofen, ketoprofen, fenoprofen, indomethacin, diclofenac and fentiazac. Process according to claim 3 wherein the active principles having antiinflammatory, analgesic and antipyretic activity are selected from naproxen, ibuprofen, ketoprofen and diclofenac. Process according to claim 1 wherein the binding agents are selected from polyvinylpyrrolidone, carboxymethylcellulose, microcrystalline cellulose, lactose, saccharose, mannitol, arabic gum, pectin and gelatin, the disintegrating agents are selected from starchs, alginates, sodium starch glycolate and reticulated polyvinylpyrrolidone, the lubricating agents are selected from magnesium stearate, talc, stearic acid and silica gel. Process according to claim 1 wherein the retarding agents are selected from methylcellulose, ethylcellulose, hydrogenated castor oil, hydrogenated peanut oil, hydrogenated cotton seed oil and mixtures thereof. Process according to claim 1 wherein the granulate having immediate release contains from 60% to 70% of the active principle, from 20% to 30% of binding agents, from 8% to 12% of disintegrating agents and from 0.2% to 1% of lubricating agents. Process according to claim 1 wherein the granulate having controlled release contains from 60% to 70% of the active principle and from 30% to 40% of a retarding agent selected from ethylcellulose, methylcellulose, polyvinylacetate, methacrylic acid esters, cellulose acetate, fatty alcohols containing from 12 to 32 carbon atoms, glyceric esters of fatty acids containing from 13 to 22 carbon atoms, esters of fatty acids and alcohols having from 12 to 31 carbon atoms, paraffin, beeswax, unbleached wax, candelilla wax, carnauba wax, sealing wax, spermaceti, ozokerite, hydrogenated vegetable oils and mixtures thereof. Process according to claim 8 wherein the retarding agents are defined as in claim 6.

Inventors: MARCHI, EGIDIO, ROTINI, LEONE GABRIELE
Applicants: ALFA WASSERMANN S.P.A.
Application year: 1987
Main classification: A61K9
IPC codes: A61K9, A61P25, A61P29, A61K31