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AssigneeISP Investments Inc.
InventorsRobert B. Login, Mohammed Tazi, Jui-Chang Chuang, Rama K. Haldar, Dinesh Jaiswal, Chi-San Wu
Estimating the term…
A pharmaceutical tablet is provided herein having an effective dissolution rate. The tablet contains a pharmaceutically-active ingredient and a substantially linear, i.e. non-crosslinked K-30 to K-120 PVP as a binding agent. The PVP used herein is made by an initiated polymerization process in which vinyl pyrrolidone monomer is polymerized in the presence of an initiator which produces a linear PVP polymerization, i.e. is a poor hydrogen abstractor of PVP polymer backbones, which would produce a disadvantageous crosslinked PVP product. Suitable initiators include low energy peroxyester free radical initiators, such as t-amylperoxy pivalate, an azo initiator, or a redox initiator which can perform at low temperatures. Preferably the residual initiator level in the PVP is reduced to less than 500 ppm, thereby further precluding the possibility of crosslinking of the PVP polymer during the shelf-life of the tablet.
A pharmaceutical tablet having a predetermined dissolution rate upon a given shelf-life consisting essentially of an active pharmaceutical ingredient and PVP as a binder therefor, said PVP being prepared by polymerizing vinyl pyrrolidone in the presence of a polymerization initiator selected from the group consisting of a peroxyester free radical initiator whose thermal homolysis reaction provides free radicals which are weak hydrogen abstractors, an axo initiator, and a redox initiator, and said PVP is characterized by being a linear, non-crosslinked polymer which is water soluble, wherein said PVP has a residual initiator level of less than 500 ppm achieved without crosslinking by heat decomposition of the initiator after polymerization.
A pharmaceutical tablet having a predetermined dissolution rate upon a given shelf-life consisting essentially of an active pharmaceutical ingredient and PVP as a binder therefor, said PVP being prepared by polymerizing vinyl pyrrolidone in the presence of a polymerization initiator selected from the group consisting of a peroxyester free radical initiator whose thermal homolysis reaction provides free radicals which are weak hydrogen abstractors, an azo initiator, and a redox initiator, and said PVP is characterized by being a linear, non-crosslinked polymer which is water soluble, wherein said PVP has a residual initiator level of less than 500 ppm achieved without crosslinking by decomposition of the initiator after polymerization, and wherein said PVP is subjected to a post-heat treatment at about 60.degree.-85.degree. C. to reduce the initiator level to less than 500 ppm.
Dependencies are inferred from the claim text.