§
Luxuse
Patent Intelligence
Sign In
← Back to Patent Explorer
US4673564A Expired / Lapsed US ⏱️ 0.0 years remaining

Sustained release pharmaceutical composition of solid medical material

Assignee: Astellas Pharma Inc
•
Filing: 1985-10-23
•
Granted: 1987-06-16
•
Expires: 2005-10-23
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Sustained release pharmaceutical compositions of a solid medical material which contains an amorphous solid medical material, polyethylene oxide, and at least one basic substance selected from the group consisting of hydroxypropylmethyl cellulose, hydroxypropyl cellulose, methyl cellulose, polyvinyl pyrrolidone, carboxyvinyl polymer, hydroxypropylmethyl cellulose phthalate, cellulose acetate phthalate, methyl meta-acrylate meta-acrylic acid copolymer, polyvinylacetal diethylaminoacetate, dimethylaminoethyl meta-acrylate meta-acrylic acid copolymer, 2-methyl-5-vinylpyridinemethyl acrylate meta-acrylic acid copolymer, citric acid, urea, succinic acid and amino acid, and may further contain one basic substance selected from the group consisting of a surface active agent, polyethylene glycol, propylene glycol, glycerin, a glycerin fatty acid ester and a vegetable oil (first embodiment); and in the case where the solid medical material in nicardipine, the composition may consist only of the amorphous nicardipine or a salt thereof without the above compound (second embodiment).

Inventors

  • 👤 Hiroitsu Kawata
  • 👤 Masayoshi Aruga
  • 👤 Tadayoshi Ohmura
  • 👤 Takashi Sonobe
  • 👤 Satoru Yoneya
  • 👤 Chiharu Sone

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 11:45
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/14; A61K9/141; A61K9/146; A61K31/00; A61K31/33; A61K31/395; A61K31/435; A61K31/44; A61K9/16; A61K9/1605; A61K9/1611

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 55 words
A process for producing amorphous nicardipine or its salt which comprises friction-pulverizing crystalline nicardipine or its salt to a fine powder using a ball mill or a vibrating ball mill for a period of at least 10 to 16 hours whereby said crystalline nicardipine or its salt is converted to amorphous nicardipine or its salt.
Claim 2
Dependent Claim 55 words
A process for producing amorphous nicardipine or its salt which comprises friction-pulverizing crystalline nicardipine or its salt to a fine powder using a ball mill or a vibrating ball mill for a period of at least 10 to 16 hours whereby said crystalline nicardipine or its salt is converted to amorphous nicardipine or its salt.
Claim 3
Dependent Claim 35 words
A process according to claim 1 wherein at least one anti-adherence or antimassing agent is present for decreasing the adherence and massing of nicardipine during friction-pulverizing in order to completely pulverize nicardipine to fine powder.
Claim 4
Dependent Claim 23 words
A process according to claim 2 wherein the substance is selected from the group consisting of calcium lactate, hydroxypropylmethyl cellulose and crystalline cellulose.
Claim 5
Dependent Claim 12 words
A process according to claim 3 wherein the substance is hydroxypropylmethyl cellulose.
Claim 6
Dependent Claim 15 words
A process according to claim 1 wherein friction-pulverizing is effected by a vibrating ball mill.

References Cited (Backward Citations)

US4151273A Cited
US4412986A Cited
US4344934A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-06-15 1990-12-15 1991-06-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-06-15 1994-12-15 1995-06-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-06-15 1998-12-15 1999-06-16 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag