Drug – bio-affecting and body treating compositions – Designated organic active ingredient containing – Heterocyclic carbon compounds containing a hetero ring...
Reexamination Certificate
1999-12-10
2004-04-27
Pryor, Alton (Department: 1616)
Drug, bio-affecting and body treating compositions
Designated organic active ingredient containing
Heterocyclic carbon compounds containing a hetero ring...
C514S202000, C514S772400
Reexamination Certificate
active
06727243
ABSTRACT:
The present invention relates to &bgr;-lactam compositions, specifically in respect with cefuroxime axetil which is the 1-acetoxyethyl ester of cefuroxime and which is a well known second generation cephalosporin antibiotic, e.g. useful in the treatment of microbial infections, e.g. described in The Merck Index, 12th edition, p. 324 and 325, no. 2002. The in vivo active ingredient in cefuroxime axetil is cefuroxime because in vivo the carboxylic ester in position 4 of the ring system is split off, the carboxylic acid is set free and the compound cefuroxime is formed.
Cefuroxime axetil, e.g. in crystalline form or in amorphous form, may for example be administered orally, e.g. in the form of, e.g. film-coated, tablets, or in the form of a dry powder which may e.g. be administered as such, e.g. together with an aqueous liquid or, reconstituted with an aqueous liquid, e.g. water, in the form of a suspension/syrup. However cefuroxime axetil in crystalline or in amorphous form may undergo gelatination, e.g. it may form a gelatinous mass, in contact with an aqueous liquid, e.g. water or salvia; e.g. a gel may be formed on the surface of, e.g. galenically formulated, cefuroxime axetil particles. Gelatination, e.g. gel formation on the surface of, e.g. galenically formulated, cefuroxime axetil particles, may result in poor dissolution of cefuroxime axetil, with e.g. the consequence that adsorption of cefuroxime axetil from the gastrointestinal tract may be reduced.
It was now surprisingly found that gelatination of cefuroxime axetil, e.g. gel formation on the surface of, e.g. galenically formulated, cefuroxime axetil particles, upon contact with an aqueous liquid may be, e.g. substantially, avoided if cefuroxime axetil is neither in crystalline nor amorphous form, but in non-gelatinous form on contact with an aqueous liquid.
Although it is not intended to be bound on any theory it is believed that in a non-gelatinous form on contact with an aqueous liquid according to the present invention cefuroxime axetil may be incorporated in a polymer in the form of a molecular dispersion which is a solid solution of cefuroxime axetil in the polymer; and/or in the form of a surface solid (molecular) dispersion on an adsorbent.
A non-gelatinous form, e.g. galenically formulated, of cefuroxime axetil, e.g. which does not form a gel on the surface of cefuroxime particles, on contact with an aqueous liquid according to the present invention and as used herein includes a form of cefuroxime axetil, e.g. galenically formulated cefuroxime axetil, e.g. a dosage form, e.g. solid, e.g. containing cefuroxime axetil as active ingredient and pharmaceutically acceptable excipients, having a dissolution rate of the active ingredient at 37° C. in aqueous medium, e.g. acidic, e.g. hydrochloric acid-acidic, e.g. buffered, which is higher, equal, or not lower
than 5% at a pH of around 1, e.g. at pH 1 after 10 to 15 minutes from the start of the dissolution test; and/or
than 20% at a pH<0 after 25 to 30 minutes from the start of the dissolution test, than the dissolution rate of the active ingredient at a pH of around 4, e.g. at pH 4.
Cefuroxime axetil in non-gelatinous form on contact with an aqueous liquid thus includes cefuroxime axetil in a form, e.g. galenically formulated, having a dissolution rate which is substantially pH independent, e.g. at pH<0, pH 1, and pH 4.
An appropriate method to determine said dissolution rate includes e.g. a method as conventional, e.g. determining the dissolution rate of cefuroxime axetil, e.g. in a dosage form, as set forth in USP(US Pharmacopaea) test <711> in a USP-2 apparatus under conditions at least as stringent as the following: 900 ml of an aqueous medium, 37° C. with paddles turning at 55 rpm; determining an average dissolution rate of at least 6 samples, containing substantially the same amount of cefuroxime axetil, and substantially the same excipients in substantially the same amount; at appropriate pH, e.g. at (around) pH 4, at (around) pH 1 and pH<0. Dosage forms which pass this test under more stringent conditions, e.g. lower volume of aqueous medium, lower temperature, lower paddle speed, are also included under the above definition. An appropriate aqueous medium useful for determination at pH 4 comprises e.g. an acetate buffer (pH 4) e.g. according to USP; and for determination at (around) pH 1 and pH<0 an hydrochloric acid-acidic aqueous solution having the appropriate pH. Detection of the dissolution rate of cefuroxime axetil at a defined time point may be carried out according to a method as conventional, e.g. by means of UV, HPLC.
In one aspect the present invention provides cefuroxime axetil in a non-gelatinous form on contact with an aqueous liquid, e.g. water, e.g. in the form of a solid solution in a polymer; e.g. in a weight ratio of cefuroxime axetil:polymer of 1:0.1 to 1:0:8, e.g. 1:0.15 to 1:08, such as 1:0.15 to 1:06, e.g. 1:0.35 to 1:0.6, e.g. 1:0.35 to 1:0.55, e.g. 1:0.35 to 1.0.45; or in the form of a surface solid dispersion on an adsorbent, e.g. in a weight ratio cefuroxime axetil:adsorbent of 1:0.1 to 1:1.5; e.g. 1:03 to 1.1.3, preferably in the form of a solid solution in a polymer.
Cefuroxime axetil in non-gelatinous form, e.g. in the form of a solid solution in a polymer or in surface solid dispersion may be e.g. obtained as follows: A solution or suspension of cefuroxime axetil in free form, e.g. in crystalline form, or in amorphous form, e.g. in the form of a solvate or in non-solvate form, and of a polymer and/or of adsorbent may be produced in organic solvent, e.g. in the presence of water.
A polymer includes polymer, e.g. one or more, which is able to form a solid solution of cefuroxime axetil in a polymer, e.g. according to the definition of cefuroxime axetil in non-gelatinous form on contact with an aqueous liquid as indicated above, preferably polymer which is soluble in the solvent (system) used. A polymer includes preferably a pharmaceutically acceptable polymer, e.g. a homo- and a copolymer, e.g. a homo- and a copolymer of a polyvinylpyrrolidone, e.g as commercially available under the trade name Kollidon®, e.g a homopolymer such as a povidone, cross-linked povidone, e.g. crospovidone, polyplasdone; and a polyvinylpyrrolidone copolymer; polyethylene glycol, polyethylene oxide, cellulose. Cellulose include alkylcelluloses, e.g. methyl-, ethyl-, propylcelluloses; hydroxalkylcelluloses, e.g. hydroxymethylcellulose, hydroxyethylcellulose, hydroxyproylcellulose; hydroxypropylmethylcellulose, and a cellulose which is, e.g. chemically, modified, e.g. which carry carboxyl groups as substituents, such as a carboxymethylcellulose. Preferred is a polyvinylpyrrolidone, e.g. as commercially available under the trade name Kollidon®, e.g. povidone, cross-linked povidone, e.g. crospovidone or polyplasdone, polyvinylpyrrolidone copolymer, celluloses, e.g. alkylcelluloses, hydroxylkylcelluloses, hydroxymethylpropylcelluloses; for example ethyl- and propylcelluloses, hydroxymethylcellulose, hydroxyethylcellulose, hydroxypropylmethylcellulose, a cellulose which is, e.g. chemically, modified, e.g. which carry carboxyl groups as substituents, polyethylene oxide, crospovidone and polypalsdone, and a copolymer of polyvinylpyrrolidone. Preferred is a polyvinylpyrrolidone copolymer, such as vinylpyrrolidone-vinylacetate copolymer, e.g. consisting of N-vinyl-2-pyrrolidone and vinyl acetate, e.g. in a random 60:40 ratio, e.g. having units of formula
e.g. as commercially available under the trade name Kollidon® (e.g. VA64) or Plasdone® (e.g. S-630). An appropriate weight ratio of cefuroxime axetil and the polymer include a ratio of 1:0.1 to 1:0:8, e.g. 1:0.15 to 1:08, such as 1:0.15 to 1:06, e.g. 1:0.35 to 1:0.6, e.g. 1:0.35 to 1:0.55, e.g. 1:0.35 to 1.0.45.
Appropriate adsorbent includes, e.g. pharmaceutically acceptable, adsorbent, e.g. one or more, which is able to form a surface solid dispersion with cefuroxime axetil, e.g. according to the definition of cefuroxime axetil in non-gelatinous form on contact with an aqueous liquid as indic
Jennewein Herwig
Raneburger Johannes
Biochemie Gesellschaft m.b.H.
Pryor Alton
Waibel Peter J.
LandOfFree
Compositions comprising cefuroxime axetil does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Compositions comprising cefuroxime axetil, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Compositions comprising cefuroxime axetil will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3272638