US4963365A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controlled release dosage form
Assignee: Tanabe Pharma Corp
•
Filing: 1988-11-04
•
Granted: 1990-10-16
•
Expires: 2008-11-04
Abstract
Abstract A controlled release dosage form which consists essentially of a core containing a medicament; an inner coating layer composed of ethylcellulose and a hydrophobic substance; and an outer coating layer containing a medicament are disclosed. Said dosage form shows rapid increase in blood concentration of the medicament and at the same time maintains the high level of the blood concentration over a prolonged period time.
Inventors
- 👤 Masayoshi Samejima
- 👤 Kazuo Noda
- 👤 Masao Kobayashi
- 👤 Shigeyuki Ishikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:55
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/20; A61K9/48; A61K9/50; A61K9/5073; A61K9/5078
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
69 words
A controlled release pharmaceutical dosage from which consists essentially of a water-soluble core containing diltiazem hydrochloride; an inner coating layer composed of ethylcellulose and a hydrophobic substance selected from the group consisting of talc and an alkali earth metal stearate, the quantitative ratio of ethylcellulose to said hydrophobic substance being in the range of about 1:1 to about 1:15 by weight; and an outer coating layer containing diltiazem hydrochloride.
Claim 2
Dependent Claim
69 words
A controlled release pharmaceutical dosage from which consists essentially of a water-soluble core containing diltiazem hydrochloride; an inner coating layer composed of ethylcellulose and a hydrophobic substance selected from the group consisting of talc and an alkali earth metal stearate, the quantitative ratio of ethylcellulose to said hydrophobic substance being in the range of about 1:1 to about 1:15 by weight; and an outer coating layer containing diltiazem hydrochloride.
Claim 3
Dependent Claim
76 words
The controlled release dosage form claimed in claim 1 in which a middle coating layer composed of ethylcellulose alone or a mixture of ethylcellulose and a water-soluble substance selected from the group consisting of sucrose, lactose, macrogol, mannitol and sorbitol, the quantitative ratio of said water soluble substance to said ethylcellulose being in the range of about 1:1 to about 20:1 by weight, is further formed between the inner coating layer and the outer coating layer.
Claim 4
Dependent Claim
40 words
The controlled release dosage form claimed in claim 2, in which the quantitative ratio of the medicament incorporated in the core to the medicament incorporated in the outer coating layer is within a range of 1:1 to 20:1 (by weight).
Claim 5
Dependent Claim
85 words
The controlled dosage form claimed in claim 3, in which the particle size of the medicament-containing core is in the range of 300 μm to 2000 μm in diameter, the coating ratio [(weight of ethylcellulose + hydrophobic substance/weight of the medicament-containing core) × 100] of the inner coating layer is in the range of 5-50%, and the amount of ethylcellulose to be used in the middle coating layer is in the range of 0.1 to 10% of the amount of the inner coating layer-coated core.
Claim 6
Dependent Claim
28 words
The controlled release dosage form claimed in claim 3, in which said dosage form is granules having a particle size of 500 μm to 2500 μm in diameter.
Claim 7
Dependent Claim
21 words
The controlled release dosage form claimed in claim 4, in which the hydrophobic substance is talc, magnesium stearate or calcium strearate.
Claim 8
Dependent Claim
16 words
The controlled release dosage form claimed in claim 6, in which the hydrophobic substance is talc.
References Cited (Backward Citations)
GB857550A
Cited
US2921883A
Cited
US2928770A
Cited
US3492397A
Cited
EP0092060A1
Cited
US4390406A
Cited
JPS604120A
Cited
EP0149920A2
Cited
EP0148811A1
Cited
US4780318A
Cited
EP0163000A2
Cited
US4851228A
Cited
US4681755A
Cited
US4600645A
Cited
EP0220670A2
Cited
US4842867A
Cited
US4795644A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-10-15 | 1994-04-16 | 1994-10-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-10-15 | 1998-04-16 | 1998-10-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-10-15 | 2002-04-16 | 2002-10-16 | $7700.00 | Window Closed / Lapsed |