US4897267A
Expired / Lapsed
US
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Microparticles comprising a biodegradable polymer controlling the release of an antimalaria active principle, pharmaceutical compositions comprising it and process for its preparation
Assignee: La Region Wallonne
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Filing: 1988-07-28
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Granted: 1990-01-30
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Expires: 2008-07-28
Abstract
Abstract The present invention relates to microparticles containing an active principle against malaria, such as primaquine, one of its amino acid derivatives, or their conjugates with a hepatotropic vector or their pharmaceutically acceptable salts, and a biocompatible and biodegradable polymer controlling the kinetics of release of the active principle, like (DL)polylactide. The invention also relates to pharmaceutical compositions comprising microcapsules according to the invention. Lastly, the invention relates to processes for the preparation of microparticles as mentioned above, the processes comprising: dissolving the polymer in a volatile solvent, adding to this solution the active principle and possibly a substance regulating the size of the microparticles, and at the end of evaporation, recovering the microparticles by centrifugation and filtration.
Inventors
- 👤 Jose Bontemps
- 👤 Philippe Pirson
- 👤 Jean-Bernard Falmagne
- 👤 Robert Jerome
- 👤 Philippe Teyssie
- 👤 Luc Delattre
- 👤 Brigitte Evrard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:57
CPC Classifications
A; A61; A61K; A61K31/00; A61K31/33; A61K31/395; A61K31/435; A61K31/47; A61K47/00; A61K47/50; A61K47/51; A61K47/54; A61K47/542; A61K9/00; A61K9/14; A61K9/16; A61K9/1605; A61K9/1629; A61K9/1641; A61K9/1647; A61P; A61P33/00; A61P33/02; Y; Y02; Y02A; Y02A50/00; Y02A50/30
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
85 words
Microparticles consisting of microspheres constituted by a polylactide polymer matrix, within which is distributed an active principle which is primaquine, one of its derivatives of the formula PQ--X in which, PQ represents primaquine, X represents an amino acid or a peptide of 2 to 4 amino acids, the linkage PQ--X being a peptide covalent linkage between the free amine group of PQ and the carboxylic group of X, or conjugates of PQ or PQ--X with a hepatotropic vector, or one of their pharmaceutically acceptable salts.
Claim 2
Dependent Claim
85 words
Microparticles consisting of microspheres constituted by a polylactide polymer matrix, within which is distributed an active principle which is primaquine, one of its derivatives of the formula PQ--X in which, PQ represents primaquine, X represents an amino acid or a peptide of 2 to 4 amino acids, the linkage PQ--X being a peptide covalent linkage between the free amine group of PQ and the carboxylic group of X, or conjugates of PQ or PQ--X with a hepatotropic vector, or one of their pharmaceutically acceptable salts.
Claim 3
Dependent Claim
17 words
Microparticles according to claim 1, wherein the molecular weight of the polymer is between 10,000 and 200,000.
Claim 4
Dependent Claim
17 words
Microparticles according to claim 1, wherein the ratio by weight active principle/polymer is from 1 to 50%.
Claim 5
Dependent Claim
13 words
Microparticles according to claim 1, with a dimension between 1 and 250 μm.
Claim 6
Dependent Claim
9 words
Pharmaceutical composition, which contains microparticles according to claim 1.
Claim 7
Dependent Claim
9 words
Composition according to claim 5, said composition being injectable.
Claim 8
Dependent Claim
37 words
Process for the preparation of microparticles, according to claim 1, said process comprising: dissolving the polymer in a volatile solvent, adding to this solution, the active principle and after evaporation, recovering the microparticles by centrifugation and filtration.
Claim 9
Dependent Claim
54 words
Process according to claim 7, wherein the primaquine or one of its derivatives or conjugates, or one of their pharmaceutically acceptable salts is incorporated in polylactide, the solvent being acetone and the dispersing medium being a mineral oil, such as paraffin, the substance regulating the size of the particles being a non-ionic surface-active agent.
Claim 10
Dependent Claim
12 words
Process according to claim 8, wherein the polylactide is in (DL) form.
Claim 11
Dependent Claim
30 words
Process according to claim 7, wherein the ratio by weight of polymer/solvent is from 10 to 30%, and the ratio by weight of active principle/polymer is from 1 to 50%.
Claim 12
Dependent Claim
22 words
Process according to claim 7, wherein the dispersion of the active principle in the acetone is done by the use of ultrasound.
Claim 13
Dependent Claim
22 words
Process according to claim 8, comprising using as non-ionic detergent, a sorbitan ester preferably in a concentration comprised between 1 and 10%.
Claim 14
Dependent Claim
25 words
Process according to claim 8, wherein the sorbitan ester is sorbitan monooleate used in the proportion of 5% by weight with respect to the acetone.
Claim 15
Dependent Claim
14 words
Microparticles according to claim 1, wherein the polylactide polymer matrix is in (DL) form.
Claim 16
Dependent Claim
17 words
Microparticles according to claim 1, wherein the molecular weight of the polymer is between 50,000 and 100,000.
Claim 17
Dependent Claim
17 words
Microparticles according to claim 1, wherein the ratio by weight active principle/polymer is from 15 to 25%.
Claim 18
Dependent Claim
13 words
Microparticles according to claim 1, with a dimension between 100 and 200 μm.
Claim 19
Dependent Claim
31 words
Process according to claim 7, further comprising the step of adding a substance regulating the size of the microparticles to the solution of the polymer in the volatile solvent, before evaporation.
Claim 20
Dependent Claim
17 words
Process according to claim 10, wherein the ratio by weight of polymer/solvent is from 15 to 20%.
Claim 21
Dependent Claim
18 words
Process according to claim 10, wherein the ratio by weight of active principle/polymer is from 15 to 25%.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1993-01-29 | 1993-07-31 | 1994-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-29 | 1997-07-31 | 1998-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-29 | 2001-07-31 | 2002-01-30 | $7700.00 | Window Closed / Lapsed |