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US4012497A Expired / Lapsed US ⏱️ 0.0 years remaining

Drug excipient of silicone rubber

Assignee: Bayer Pharma AG
•
Filing: 1975-09-23
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Granted: 1977-03-15
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Expires: 1995-09-23
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Abstract

Abstract Nontoxic sustained release pharmaceutical compositions containing one or more nonionic, lipophilic drugs in a cured low temperature vulcanizable (LTV) silicone elastomer excipient are prepared substantially free of toxic vulcanizing agents or drug-reactive by-products in the elastomeric material by curing with a vulcanizable composition comprising A. a polydimethylsiloxane having vinyl groups on both ends; B. a copolymer consisting essentially of SiO 2 units, (CH 3 ) 3 SiO 0 .5 units, Vinyl(CH 3 ) 2 SiO 0 .5 units; and C. a cross-linking Si-H component, consisting essentially of (CH 3 ) 3 SiO 0 .5 units, (CH 3 ) 2 SiO units, and CH 3 HSiO units. The resultant compositions are characterized by good physical properties and a constant rate of drug release in the body over long periods of time.

Inventors

  • 👤 Gisela Schopflin

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-22 19:26
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/0012; A61K9/0019; A61K9/0024; A61K9/0034; A61K9/0039; A61K9/20; A61K9/2004; A61K9/2022; A61K9/2031; A61K9/2036

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 129 words
A non-toxic sustained release pharmaceutical composition in the form of a shaped object having a Shore A hardness of 45-70, consisting essentially of a safe and pharmaceutically active amount of a nonionic lipophilic drug having a dissociation constant of less than 10.sup. -7 and which is olefinically or acetylenically unsaturated and soluble in ether, chloroform or benzene, said drug being dissolved or uniformly suspended in a non-toxic vulcanized LTV linear dimethylpolysiloxane elastomer and said composition being prepared by reacting, at an elevated temperature and in contact with a catalytic amount of a platinum-based vulcanization catalyst capable of catalyzing the reaction between silicon-linked hydrogen residues and silicon-linked vinyl residues a mixture of said drug and a vulcanizable composition consisting essentially of: a. a polydimethylsiloxane having vinyl groups on both ends;
Claim 2
Dependent Claim 129 words
A non-toxic sustained release pharmaceutical composition in the form of a shaped object having a Shore A hardness of 45-70, consisting essentially of a safe and pharmaceutically active amount of a nonionic lipophilic drug having a dissociation constant of less than 10.sup. -7 and which is olefinically or acetylenically unsaturated and soluble in ether, chloroform or benzene, said drug being dissolved or uniformly suspended in a non-toxic vulcanized LTV linear dimethylpolysiloxane elastomer and said composition being prepared by reacting, at an elevated temperature and in contact with a catalytic amount of a platinum-based vulcanization catalyst capable of catalyzing the reaction between silicon-linked hydrogen residues and silicon-linked vinyl residues a mixture of said drug and a vulcanizable composition consisting essentially of: a. a polydimethylsiloxane having vinyl groups on both ends;
Claim 3
Dependent Claim 54 words
b. a copolymer consisting essentially of SiO 2 units, (CH 3 ) 3 SiO 0 .5 units, Vinyl (CH 3 ).sub. 2 SiO 0 .5 units; and c. a cross-linking Si-H component, consisting essentially of (CH 3 ) 3 SiO 0 .5 units, (CH 3 ) 2 SiO units and CH 3 HSiO units.
Claim 4
Dependent Claim 54 words
b. a copolymer consisting essentially of SiO 2 units, (CH 3 ) 3 SiO 0 .5 units, Vinyl (CH 3 ).sub. 2 SiO 0 .5 units; and c. a cross-linking Si-H component, consisting essentially of (CH 3 ) 3 SiO 0 .5 units, (CH 3 ) 2 SiO units and CH 3 HSiO units.
Claim 5
Dependent Claim 19 words
A pharmaceutical composition according to claim 1, further comprising a catalytic amount of a platinum metal-based catalyst dissolved therein.
Claim 6
Dependent Claim 181 words
A pharmaceutical composition according to claim 1, wherein component a) comprises 20-100 parts by weight of vinyl terminated linear organopolysiloxane having a viscosity of 500-200,000 centistokes (at 25° C.) of the general formula: ##EQU2## wherein R 2 is lower alkyl and n is an integer of about 200-1600; b. comprises 0-50 parts by weight of an organopolysiloxane copolymer consisting essentially of: i. R' 3 SiO 0 .5 units ii. R' 2 ViSiO 0 .5 units, and iii. SiO 2 units wherein Vi is a vinyl group, R' 2 and R' 3 are each a saturated, lower alkyl, at least 50% of R' being methyl; and c. comprises 5-15 parts by weight of an organohydrogen polysiloxane of the general formula ##STR3##wherein R" is lower alkyl, a and b are each positive numbers, the ratio of a:b is 0.5-10; the sum of a+b is 1-2.5; at least three hydrogen atoms linked to different Si atoms are present per molecule; and said component contains 50-500 molar percent, based on unsaturated end groups contained in components (a) and (b), of vinyl groups attached to Si-H.
Claim 7
Dependent Claim 16 words
A pharmaceutical composition according to claim 3 adapted for implantation into a human or animal body.
Claim 8
Dependent Claim 14 words
A pharmaceutical composition according to claim 3 in the form of a prosthetic device.
Claim 9
Dependent Claim 13 words
A pharmaceutical composition according to claim 3 wherein said medicament is a steroid.
Claim 10
Dependent Claim 16 words
A pharmaceutical composition according to claim 3 in a form suitable for intrauterine or intravaginal administration.
Claim 11
Dependent Claim 14 words
A pharmaceutical composition according to claim 7 in the form of a vaginal ring.
Claim 12
Dependent Claim 13 words
A pharmaceutical composition according to claim 8, wherein said medicament is a steroid.

References Cited (Backward Citations)

US3279996A Cited
US3545439A Cited
US3920805A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-03-14 1980-09-13 1981-03-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-03-14 1984-09-13 1985-03-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-03-14 1988-09-13 1989-03-15 $7700.00 Window Closed / Lapsed

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