GB2151921A - Controlled release form of ketoprofen for oral administration - Google Patents
Controlled release form of ketoprofen for oral administration Download PDFInfo
- Publication number
- GB2151921A GB2151921A GB08431987A GB8431987A GB2151921A GB 2151921 A GB2151921 A GB 2151921A GB 08431987 A GB08431987 A GB 08431987A GB 8431987 A GB8431987 A GB 8431987A GB 2151921 A GB2151921 A GB 2151921A
- Authority
- GB
- United Kingdom
- Prior art keywords
- ketoprofen
- tablet
- gastro
- resistant coating
- oral administration
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
- A61K9/00—Medicinal preparations characterised by special physical form
- A61K9/20—Pills, tablets, discs, rods
- A61K9/2004—Excipients; Inactive ingredients
- A61K9/2022—Organic macromolecular compounds
- A61K9/205—Polysaccharides, e.g. alginate, gums; Cyclodextrin
- A61K9/2054—Cellulose; Cellulose derivatives, e.g. hydroxypropyl methylcellulose
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
- A61K31/00—Medicinal preparations containing organic active ingredients
- A61K31/185—Acids; Anhydrides, halides or salts thereof, e.g. sulfur acids, imidic, hydrazonic or hydroximic acids
- A61K31/19—Carboxylic acids, e.g. valproic acid
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
- A61K9/00—Medicinal preparations characterised by special physical form
- A61K9/20—Pills, tablets, discs, rods
- A61K9/28—Dragees; Coated pills or tablets, e.g. with film or compression coating
- A61K9/2806—Coating materials
- A61K9/2833—Organic macromolecular compounds
- A61K9/286—Polysaccharides, e.g. gums; Cyclodextrin
- A61K9/2866—Cellulose; Cellulose derivatives, e.g. hydroxypropyl methylcellulose
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
- A61P29/00—Non-central analgesic, antipyretic or antiinflammatory agents, e.g. antirheumatic agents; Non-steroidal antiinflammatory drugs [NSAID]
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- Health & Medical Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Medicinal Chemistry (AREA)
- Pharmacology & Pharmacy (AREA)
- Life Sciences & Earth Sciences (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Epidemiology (AREA)
- Pain & Pain Management (AREA)
- Rheumatology (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Bioinformatics & Cheminformatics (AREA)
- Acyclic And Carbocyclic Compounds In Medicinal Compositions (AREA)
- Medicinal Preparation (AREA)
Abstract
Sustained release tablets for oral administration of ketoprofen comprise ketoprofen in a hydrophilic matrix covered with a gastro-resistant coating.
Description
SPECIFICATION
Controlled release form of ketoprofen for oral administration
The present invention relates to compositions for oral administration containing 2-(3-benzoylphenyl)propionic acid, a powerful non-steroidal anti-inflammatory agent known as ketoprofen.
Ketoprofen is absorbed very rapidly from the upper part of the digestive tract. It has a short half-life and is rapidly eliminated.
The usual forms of ketoprofen for oral administration, such as gelatin capsules, which have a rapid rate of dissolution, do not modify the rate of absorption of ketoprofen, and it is necessary, for an effective dosage to take 2 gelatin capsules containing a 50 mg dose 2 to 3 times a day. As a result, the repeated administration is accompanied by peaks of relatively high maximum plasma concentration, which can cause gastric intolerance phenomena.
It is advantageous to be able to dispense to patients a controlled release form of ketoprofen for oral administration which permits gradual release of the ketoprofen, so as to reduce the number of administrations per day, to level out the peaks of maximum concentration, and to maintain a therapeutically effective plasma concentration for at least 12 hours.
It has now been found that tablets can be made which make it possible to control the release of ketoprofen.
According to the present invention, controlled release tablets for oral administration of ketoprofen comprise ketoprofen in a hydrophilic matrix covered with a gastro-resistant coating.
The gastro-resistant coating makes it possible to avoid any direct contact between the irritant active substance and the gastric mucous membrane. Disaggregation of the gastro-resistant coating takes place beyond the stomach by virtue of the pH difference which exists between the gastric liquid and the intestinal liquids. Free of its coating, the hydrophilic matrix can then play its part in regulating the release of the active principle.
The manner in which the hydrophilic matrix functions can be schematically broken down into three stages:
1) Under the effect of the intestinal fluids, a gelled barrier forms on the surface by hydration and gelling of the polymer which makes up the hydrophilic matrix. The few particles of active principle which are near the surface of the tablet dissolve at the same time; this portion constitutes the initial dose.
2) Water penetrates into the tablet and, in return, the active principle diffuses into solution. The water advances concentrically into the tablet and permits hydration of the hydrophilic polymer to give new gelled barriers at increasing depth, which in turn permit release of ketoprofen. The active principle dissolves at the water penetration front and diffuses through the gelled barrier.
3) The hydrogels formed by the gelled barriers are gradually destroyed starting from the surface of the tablet most exposed to the intestinal fluids. Two phenomena compete in the structure breakdown of these hydrogels: the dissolution of the skeleton formed by the active principle in solid form, and the loosening of the polymer network associated with swelling of the polymer.
For this complex system of structure formation breakdown of the viscous barriers to function appropriately, the swelling of the hydrophilic polymer must be capable of creating a gelled barrier on the surface without causing the tablet to disaggregate; there is competition between the gelling effect, which fuses the body of the tablet, and the disintegrating effect, which tends to disperse it. Numerous parameters take part in this competition, among which there may be mentioned the viscosity of the hydrophilic polymer in aqueous solution, its hydration rate, its gelling rate and also its particle size and its concentration in the tablet. It is therefore particularly advantageous to use a hydrophilic polymer whose viscosity in aqueous solution is high but compatible with the formation of the gelled barrier on the surface in a suitable time.
Furthermore, the hydrophilic polymer must be compatible with the active substance and pharmaceutically acceptable.
The hydrophilic polymers which are particularly suitable are chosen from cellulose derivatives such as hydroxyethylcellulose, hydroxypropylcellulose or hydroxypropylmethylcellulose. It is particularly advantageous to use hydroxyethylcellulose and more especially Natrosol 250 HHX (registered trademark of the
Hercules company).
Hydroxyethylcellulose permits the formation, within the tablet, after immersion in an aqueous phase, a gastric medium or an intestinal medium, of a hydrophilic matrix regulating the release of the ketoprofen.
This polymer, which is compatible with ketoprofen, has the advantage of a gelling rate which is sufficient to prevent disaggregation of the tablet while at the same time forming a crosslinking network suitable for controlled release of the active principle. Hydroxyethylcellulose has a high viscosity in aqueous solution and a fine particle size and it gives a good compressibility to the granules. The gastro-resistant coating has the effect of further delaying the release of the ketoprofen and of preventing any direct contact between the irritant active substance and the gastric mucous membrane. The gastro-resistant coating is preferably cellulose acetophthalate, but other gastro-resistant polymers can be used.
The tablets according to the invention can contain other adjuvants such as diluents (e.g. dicalcium phosphate, starch, lactose and microcrystalline cellulose), binders (e.g. polyvinylpyrrolidone and starch paste), wetting agents, lubricants (e.g. magnesium stearate, polyoxyethylene glycols and colloidal silicas) and colourants.
In general, a tablet according to the invention contains from 10 to 80% by weight of ketoprofen, from 10 to 60% by weight of hydrophilic polymers and from 0.5 to 10% by weight of gastro-resistant coating.
According to a feature of the invention, the new controlled release tablets are made by preparing granules containing the ketoprofen, one or more hydrophilic polymers, and optionally one or more adjuvants, e.g. as described above, compressing the granules to give tablets containing the required quantity of ketoprofen, and covering the tablets by lacquering with a gastro-resistant coating.
Depending on the particular case, the method of preparation of the granules will involve dry granulation, wet granulation or so-called direct compression. The granules are then compressed to give tablets containing the required quantity of ketoprofen. Finally, the tablets are covered with a gastro-resistant coating by lacquering, e.g. with a solution of cellulose acetophthalate.
The controlled-release ketoprofen tablets according to the present invention make it possible to prevent any contact between the particles of ketoprofen and the gastric mucous membrane, to level out the peaks of maximum plasma concentrations which would be obtained with an immediate-release form of ketoprofen, to maintain a plasma concentration which is still detectable after about 24 hours, and to produce a form which is bio-equivalentto ordinary gelatin capsules.
The Examples which follow show how the invention can be put into practice.
Example 1
Granules (5 kg) having the following composition are prepared:
ketoprofen ........................................ 40%
dicalcium phosphate ........................................ 48%
hydroxyethylcellulose ........................................ 10%
magnesium stearate ........................................ 2%
A mixture of the first three constituents is granulated with water and the granules are then dried at 45 C for
20 hours in a ventilated oven. The dry granules are brought to a uniform size by passage through a sieve of 1
mm mesh size and then lubricated by mixing with the 2% of magnesium stearate.
The granules are compressed using either a reciprocating or a rotary compressor, the unit weight of the tablet being adjusted so that each tablet contains the chosen dose of ketoprofen (i.e. 500 mg for a tablet
containing a 200 mg dose of ketoprofen).
The gastro-resistant lacquer is applied by spraying a solution having the following composition:
cellulose acetophthalate ........................................ 5%
ethyl phthalate ........................................ 1.25%
ethyl acetate ........................................ 46.875%
denatured ethyl alcohol ........................................ 46.875%
onto the tablets rotating in a turbine, at a rate of 500 g per kilogram of tablets, using a compressed air gun.
After the lacquered tablets have dried for 2 hours at 45 C and then for 16 hours at a temperature of the
order of 20 C, the quantity of gastro-resistant lacquer corresponds to 3% of the weight of the coated tablets.
Example 2
The procedure of Example 1 is followed, but the unit weight of the tablets is adjusted to 250 mg to give a
tablet containing a 100 mg dose of ketoprofen.
Example 3
The procedure of Example 1 is followed, but the unit weight of the tablets is adjusted to 375 mg to give a tablet containing a 150 mg dose of ketoprofen.
The efficacy of the tablets of the present invention has been demonstrated in vitro and in vivo.
In vitro, the dissolution rate of a controlled-release tablet containing a 200 mg dose of ketoprofen is compared with the dissolution rate of an immediate-release form containing a 200 mg dose of ketoprofen, according to the USP technique using a rotating basket with changing of the medium. The results are collated in Table 1.
TABLE I
Dissolution Sampling Percentage of ketoprofen dissolved
Medium time
Immediate- Controlled
release form release form
30 minutes 75%
pH = 1 60 minutes 97%
2 hours 100% 1%
1 hour - 15%
3 hours - 27% pH = 7.4
5 hours - 37% 21 hours - 90%
In vivo, the rate of release can be monitored by measuring the plasma concentrations (in Fg/cc) after a single oral administration, to a healthy man, of a controlled-release tablet containing a 200 mg dose of ketoprofen and of an immediate-release form containing the same 200 mg dose. The results are collated in
Table II, which gives the averages obtained for 10 subjects treated.
TABLE II
Controlled-release form Immediate-release form
Time Average Standard Time Average Standard
(hours) plasma deviation (hours) plasma deviation
concentration concentration
0.75 11.31 7.63
1.00 0.00 0.02 1.00 14.62 6.72
1.25 13.73 5.55
1.50 12.41 3.98
1.75 12.92 3.97
2.00 0.57 0.91 2.00 11.16 3.93
2.50 9.42 4.12
3.00 1.96 1.76 3.00 6.96 3.39
3.50 2.40 1.48
4.00 2.34 1.06 4.00 4.06 1.61
4.50 2.39 0.98
5.00 2.44 0.55 5.00 2.40 0.74
5.50 2.51 0.57
6.00 2.62 0.85
6.50 2.61 0.87
7.00 2.65 1.00 7.00 0.93 0.33
7.50 2.54 0.99
8.00 2.41 0.94
9.00 2.56 1.03 9.00 0.38 0.07
13.00 2.25 0.98 13.00 0.15 0.13
17.00 1.40 0.47
20.00 0.87 0.31
24.00 0.64 0.52 24.00 0.04 0.06
Claims (9)
1. A controlled release tablet for oral administration of ketoprofen, comprising ketoprofen in a hydrophilic matrix covered with a gastro-resistant coating.
2. A tablet according to claim 1, wherein the hydrophilic matrix is a cellulose derivative.
3. Atablet according to claim 2, wherein the cellulose derivative is hydroxyethylcellulose, hydroxypropy Icellulose or hydroxypropylmethylcellulose.
4. A tablet according to any of claims 1 to 3, wherein the gastro-resistant coating is cellulose acetophthalate.
5. A tablet according to any of claims 1 to 4, which also contains an adjuvant.
6. A tablet according to any of claims 1 to 5, which contains from 10 to 80% by weight of ketoprofen, from 10 to 60% by weight of the hydrophilic matrix and from 0.5 to 10% by weight of the gastro-resistant coating.
7. A tablet according to claim 1 substantially as hereinbefore described in Example 1,2 or 3.
8. A process for the preparation of a tablet according to any of claims 1 to 6, which comprises preparing granules containing the ketoprofen, one or more hydrophilic polymers, and optionally one or more adjuvants, compressing the granules to give a tablet containing the required quantity of ketoprofen, and covering the tablet by lacquering with a gastro-resistant coating.
9. A controlled release tablet for oral administration of ketoprofen, comprising ketoprofen in a hydrophilic matrix covered with a gastro-resistant coating when prepared by the process claimed in claim 8.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR8320470A FR2556965B1 (en) | 1983-12-21 | 1983-12-21 | NEW GALENIC FORM OF CONTROLLED RELEASE KETOPROFEN |
Publications (3)
Publication Number | Publication Date |
---|---|
GB8431987D0 GB8431987D0 (en) | 1985-01-30 |
GB2151921A true GB2151921A (en) | 1985-07-31 |
GB2151921B GB2151921B (en) | 1988-08-03 |
Family
ID=9295398
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB08431987A Expired GB2151921B (en) | 1983-12-21 | 1984-12-19 | Controlled release form of ketoprofen for oral administration |
Country Status (3)
Country | Link |
---|---|
JP (1) | JPH0635383B2 (en) |
FR (1) | FR2556965B1 (en) |
GB (1) | GB2151921B (en) |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0212745A2 (en) * | 1985-08-16 | 1987-03-04 | The Procter & Gamble Company | Drug particles having constant release |
EP0212746A2 (en) * | 1985-08-16 | 1987-03-04 | The Procter & Gamble Company | Drug particles having constant release |
EP0253541A2 (en) | 1986-07-09 | 1988-01-20 | Merck Sharp & Dohme Ltd. | Sustained release pharmaceutical compositions in oral dosage form |
EP0325086A2 (en) * | 1987-11-23 | 1989-07-26 | Jago Research Ag | Novel methods for obtaining therapeutic systems with controlled release of the drug |
FR2667242A1 (en) * | 1990-09-28 | 1992-04-03 | Rhone Poulenc Sante | New sustained-release oral dosage forms with a reduced latency time in the stomach |
US5651983A (en) * | 1993-02-26 | 1997-07-29 | The Procter & Gamble Company | Bisacodyl dosage form for colonic delivery |
US5686106A (en) * | 1995-05-17 | 1997-11-11 | The Procter & Gamble Company | Pharmaceutical dosage form for colonic delivery |
US5843479A (en) * | 1993-02-26 | 1998-12-01 | The Procter & Gamble Company | Bisacodyl dosage form with multiple enteric polymer coatings for colonic delivery |
US5914132A (en) * | 1993-02-26 | 1999-06-22 | The Procter & Gamble Company | Pharmaceutical dosage form with multiple enteric polymer coatings for colonic delivery |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2727009B2 (en) * | 1989-03-10 | 1998-03-11 | ダイト株式会社 | Sustained preparation |
CN102813638A (en) * | 2011-06-07 | 2012-12-12 | 贵阳医学院 | Preparation method of dexketoprofen trometamol double-layer sustained-release tablets |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1568837A (en) * | 1975-10-10 | 1980-06-04 | Squibb & Sons Inc | Controlled release tablet |
EP0013131A2 (en) * | 1978-12-27 | 1980-07-09 | Mundipharma A.G. | Pharmaceutical composition in solid dosage form, and process for its production |
EP0014514A2 (en) * | 1979-02-02 | 1980-08-20 | Orion-Yhtymä Oy | Process for the preparation of tablets |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3247066A (en) * | 1962-09-12 | 1966-04-19 | Parke Davis & Co | Controlled release dosage form containing water-swellable beadlet |
US3909444A (en) * | 1971-08-05 | 1975-09-30 | Ncr Co | Microcapsule |
IT1168014B (en) * | 1981-08-05 | 1987-05-20 | Erba Farmitalia | PHARMACEUTICAL FORMS WITH PROTRACTED SALE |
US4369172A (en) * | 1981-12-18 | 1983-01-18 | Forest Laboratories Inc. | Prolonged release therapeutic compositions based on hydroxypropylmethylcellulose |
-
1983
- 1983-12-21 FR FR8320470A patent/FR2556965B1/en not_active Expired
-
1984
- 1984-03-19 JP JP59051310A patent/JPH0635383B2/en not_active Expired - Lifetime
- 1984-12-19 GB GB08431987A patent/GB2151921B/en not_active Expired
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB1568837A (en) * | 1975-10-10 | 1980-06-04 | Squibb & Sons Inc | Controlled release tablet |
EP0013131A2 (en) * | 1978-12-27 | 1980-07-09 | Mundipharma A.G. | Pharmaceutical composition in solid dosage form, and process for its production |
EP0014514A2 (en) * | 1979-02-02 | 1980-08-20 | Orion-Yhtymä Oy | Process for the preparation of tablets |
Non-Patent Citations (2)
Title |
---|
GB THE PHARMACEUTICAL CODEX, 11TH EDITION 1979 LONDON, (PAGES 481-182)US THE THEORY AND PRACTICE OF INDUSTRIAL PHARMACY 2ND EDITION, 1976 PHILADELPHIA PAGEE 445 PAGE 450 PAGE 452 * |
LA SEMEINE DES HOSPITAUX DE PARIS VOL 59 NO 46 P. 3240-3242 * |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0212745A2 (en) * | 1985-08-16 | 1987-03-04 | The Procter & Gamble Company | Drug particles having constant release |
EP0212746A2 (en) * | 1985-08-16 | 1987-03-04 | The Procter & Gamble Company | Drug particles having constant release |
EP0212745A3 (en) * | 1985-08-16 | 1987-11-11 | The Procter & Gamble Company | Drug particles having constant release |
EP0212746A3 (en) * | 1985-08-16 | 1987-11-11 | The Procter & Gamble Company | Drug particles having constant release |
EP0253541A2 (en) | 1986-07-09 | 1988-01-20 | Merck Sharp & Dohme Ltd. | Sustained release pharmaceutical compositions in oral dosage form |
EP0253541A3 (en) * | 1986-07-09 | 1988-04-27 | Merck Sharp & Dohme Ltd. | Sustained release pharmaceutical compositions in oral dosage form |
EP0325086A2 (en) * | 1987-11-23 | 1989-07-26 | Jago Research Ag | Novel methods for obtaining therapeutic systems with controlled release of the drug |
EP0325086A3 (en) * | 1987-11-23 | 1990-10-31 | Jago Research Ag | Novel methods for obtaining therapeutic systems with controlled release of the drug |
FR2667242A1 (en) * | 1990-09-28 | 1992-04-03 | Rhone Poulenc Sante | New sustained-release oral dosage forms with a reduced latency time in the stomach |
US5651983A (en) * | 1993-02-26 | 1997-07-29 | The Procter & Gamble Company | Bisacodyl dosage form for colonic delivery |
US5843479A (en) * | 1993-02-26 | 1998-12-01 | The Procter & Gamble Company | Bisacodyl dosage form with multiple enteric polymer coatings for colonic delivery |
US5914132A (en) * | 1993-02-26 | 1999-06-22 | The Procter & Gamble Company | Pharmaceutical dosage form with multiple enteric polymer coatings for colonic delivery |
US5686106A (en) * | 1995-05-17 | 1997-11-11 | The Procter & Gamble Company | Pharmaceutical dosage form for colonic delivery |
Also Published As
Publication number | Publication date |
---|---|
FR2556965A1 (en) | 1985-06-28 |
GB8431987D0 (en) | 1985-01-30 |
JPH0635383B2 (en) | 1994-05-11 |
GB2151921B (en) | 1988-08-03 |
FR2556965B1 (en) | 1986-08-22 |
JPS60132915A (en) | 1985-07-16 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PE20 | Patent expired after termination of 20 years |
Effective date: 20041218 |