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US4976949A Expired / Lapsed US ⏱️ 0.0 years remaining

Controlled release dosage form

Assignee: University of Michigan (System)
•
Filing: 1990-01-29
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Granted: 1990-12-11
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Expires: 2010-01-29
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Abstract

Abstract A dosage system for administering drugs and conducting gastric flow studies is configured in the form of a multiplicity of substantially spherical subunits which have advantageously preselected particle diameter and density to customize the flow rate of the subunits with respect to the rate of flow of at least certain portions of the chyme. The diameter and density are related to one another in accordance with a relationship: <IMAGE> where NV is a dimensionless group having a predetermined value representing gastric residence time, g is the gravitational constant, DELTA p is the difference in density between the subunits and the chyme, and <v> is the linear velocity of the chyme. The flow rate of the subunits can be made slower, faster, or substantially equal to that of the chyme, as required to treat certain disease states. Also, the subunits can be provided with an enteric coating which permits more precise administration of certain drugs, such as those used in enzyme supplementation therapy. This is particularly useful in treating patients with abnormal duodenal pH levels, such as are encountered in victims of cystic fibrosis and other forms of pancreatic insufficiency.

Inventors

  • 👤 James H. Meyer
  • 👤 Gordon L. Amidon
  • 👤 Jennifer B. Dressman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 22:56
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/14; A61K9/16; A61K9/1605; A61K9/1611; Y; Y10; Y10T; Y10T436/00; Y10T436/13

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 180 words
A drug dosage system of the type wherein an active drug is administered orally to a living being so as to be transported by a chyme produced by the living being in response to an ingested meal, the chyme having a solid portion, the drug dose system comprising a multiplicity of subunits of the active drug, said subunits each having a substantially spherical configuration and a predeterminable density and diameter, said density and diameter being selectably related to one another in accordance with a relationship: ##EQU4## wherein N v is functionally related to the gastric residence time of said subunits relative to the liquid fraction of the meal, g is the gravitational constant, Δp is the difference in density between said subunits and the chyme, d p is the diameter of said subunits, μ is the viscosity of the chyme, and <v> is the linear velocity of the chyme; and wherein the value of |Δp|*d p 2 is selected to achieve a predetermined rate of transport of said subunits and concomitant emptying thereof with the solid portion of the chyme.
Claim 2
Dependent Claim 180 words
A drug dosage system of the type wherein an active drug is administered orally to a living being so as to be transported by a chyme produced by the living being in response to an ingested meal, the chyme having a solid portion, the drug dose system comprising a multiplicity of subunits of the active drug, said subunits each having a substantially spherical configuration and a predeterminable density and diameter, said density and diameter being selectably related to one another in accordance with a relationship: ##EQU4## wherein N v is functionally related to the gastric residence time of said subunits relative to the liquid fraction of the meal, g is the gravitational constant, Δp is the difference in density between said subunits and the chyme, d p is the diameter of said subunits, μ is the viscosity of the chyme, and <v> is the linear velocity of the chyme; and wherein the value of |Δp|*d p 2 is selected to achieve a predetermined rate of transport of said subunits and concomitant emptying thereof with the solid portion of the chyme.
Claim 3
Dependent Claim 14 words
The drug dosage system of claim 1 wherein said subunits are nondigestible and radiolabeled.
Claim 4
Dependent Claim 18 words
The drug dosage system of claim 1 wherein there is further provided an enteric coating for said subunits.
Claim 5
Dependent Claim 41 words
The drug dosage system of claim 1 wherein said density and diameter of said subunits are selected to achieve substantially concomitant emptying of said subunits and said chyme, whereby |Δp|·d p 2 has a value of between about 0 and 0.5.
Claim 6
Dependent Claim 20 words
The drug dosage system of claim 4 wherein said density of said subunits is approximately between 0.6 and 1.4 g/ml.
Claim 7
Dependent Claim 21 words
The drug dosage system of claim 5 wherein said diameter of said subunits is approximately between 0.5 mm and 2.0 mm.
Claim 8
Dependent Claim 18 words
The drug dosage system of claim 1 wherein the active drug is selected to be a digestive enzyme.
Claim 9
Dependent Claim 18 words
The drug dosage system of claim 7 wherein there is further provided an enteric coating for said subunits.
Claim 10
Dependent Claim 22 words
The drug dosage system of claim 8 wherein said enteric coating of said subunits is selected in response to predetermined gastrointestinal conditions.
Claim 11
Dependent Claim 33 words
The drug dosage system of claim 9 wherein said predetermined gastric condition is characterized by pancreatic insufficiency and said enteric coating is dissolvable in a pH range of approximately between 4.5 and 5.5.
Claim 12
Dependent Claim 22 words
The drug dosage system of claim 5 wherein there is further provided an alkaline component for increasing the pH of said subunits.
Claim 13
Dependent Claim 14 words
The drug dosage system of claim 11 wherein said alkaline component is sodium bicarbonate.
Claim 14
Dependent Claim 202 words
A drug dosage system of the type wherein an active drug is administered orally to a living being so as to be transported by a chyme produced by the living being in response to an ingested meal, the drug dose system comprising a multiplicity of subunits of the active drug, said subunits each having a substantially spherical configuration and a predeterminable density and diameter, said density and diameter being selectably related to one another in accordance with a relationship: ##EQU5## wherein N v is functionally related to the gastric residence time of said subunits relative to a liquid fraction of the meal, g is the gravitational constant, Δp is the difference in density between said subunits and the chyme, d p is the diameter of said subunits, μ is the viscosity of the chyme, and <v> is the linear velocity of the chyme; said density of the subunits being approximately between 0.6 and 1.4 g/ml; said diameter of said subunits being approximately between 0.5 and 2.0 mm; and |Δp|*d p 2 having a value between about 0 and 0.5, whereby the subunits are transported in the living being at approximately the same rate of transport as a solid portion of a chyme.
Claim 15
Dependent Claim 202 words
A drug dosage system of the type wherein an active drug is administered orally to a living being so as to be transported by a chyme produced by the living being in response to an ingested meal, the drug dose system comprising a multiplicity of subunits of the active drug, said subunits each having a substantially spherical configuration and a predeterminable density and diameter, said density and diameter being selectably related to one another in accordance with a relationship: ##EQU5## wherein N v is functionally related to the gastric residence time of said subunits relative to a liquid fraction of the meal, g is the gravitational constant, Δp is the difference in density between said subunits and the chyme, d p is the diameter of said subunits, μ is the viscosity of the chyme, and <v> is the linear velocity of the chyme; said density of the subunits being approximately between 0.6 and 1.4 g/ml; said diameter of said subunits being approximately between 0.5 and 2.0 mm; and |Δp|*d p 2 having a value between about 0 and 0.5, whereby the subunits are transported in the living being at approximately the same rate of transport as a solid portion of a chyme.
Claim 16
Dependent Claim 14 words
The drug dosage system of claim 13 wherein said subunits are nondigestible and radiolabeled.
Claim 17
Dependent Claim 15 words
The drug dosage system of claim 13 wherein the active drug is a digestive enzyme.
Claim 18
Dependent Claim 18 words
The drug dosage system of claim 15 wherein there is further provided an enteric coating for said subunits.
Claim 19
Dependent Claim 23 words
The drug dosage system of claim 16 wherein said enteric coating is dissolvable in a pH range of approximately between 4.5 and 5.5.
Claim 20
Dependent Claim 22 words
The drug dosage system of claim 17 wherein there is further provided an alkaline component for increasing the pH of said subunits.
Claim 21
Dependent Claim 14 words
The drug dosage system of claim 18 wherein said alkaline component is sodium bicarbonate.

References Cited (Backward Citations)

GB1509866A Cited
US4115540A Cited
US4193985A Cited
GB1561613A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-12-10 1994-06-11 1994-12-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-12-10 1998-06-11 1998-12-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-12-10 2002-06-11 2002-12-11 $7700.00 Window Closed / Lapsed

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