) ( (51) International Patent Classification: TR), OAPI (BF, BJ, CF, CG, Cl, CM, GA, GN, GQ, GW, A61K9/20 (2006.01) A61K 31/205 (2006.01) KM, ML, MR, NE, SN, TD, TG). A61K9/28 (2006.01) Declarations under Rule 4.17: (21) International Application Number: — as to applicant's entitlement to apply for and be granted a PCT/IN20 19/050341 patent (Rule 4.17(H)) (22) International Filing Date: — as to the applicant's entitlement to claim the priority of the 27 April 2019 (27.04.2019) earlier application (Rule 4.17(iii)) — of inventorship (Rule 4.17(iv)) (25) Filing Language: English Published: (26) Publication Language: English — with international search report (Art. 21(3)) (30) Priority Data: 20172103875 1 27 April 2018 (27.04.2018) IN (71) Applicant: RUBICON RESEARCH PRIVATE LIMIT¬ ED [IN/IN]; Rubicon Research Private Limited, MedOne House, B - 75, Road No 33, Wagle Estate, Thane West 400604 (IN). (72) Inventors: PILGAONKAR, Pratibha; Rubicon Research Private Limited, MedOne House, B - 75, Road No 33, Wa¬ gle Estate, Thane West 400604 (IN). KARAJGI, Jayant; Rubicon Research Private Limited, MedOne House, B - 75, Road No 33, Wagle Estate, Thane West 400604 (IN). SARKAR, Shubhrangshu; Rubicon Research Pri¬ vate Limited, MedOne House, B - 75, Road No 33, Wagle Estate, Thane West 400604 (IN). PALANI, Anusha; Ru¬ bicon Research Private Limited, MedOne House, B - 75, Road No 33, Wagle Estate, Thane West 400604 (IN). (81) Designated States (unless otherwise indicated, for every kind of national protection available) : AE, AG, AL, AM, AO, AT, AU, AZ, BA, BB, BG, BH, BN, BR, BW, BY, BZ, CA, CH, CL, CN, CO, CR, CU, CZ, DE, DJ, DK, DM, DO, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, HN, HR, HU, ID, IL, IN, IR, IS, JO, JP, KE, KG, KH, KN, KP, KR, KW, KZ, LA, LC, LK, LR, LS, LU, LY, MA, MD, ME, MG, MK, MN, MW, MX, MY, MZ, NA, NG, NI, NO, NZ, OM, PA, PE, PG, PH, PL, PT, QA, RO, RS, RU, RW, SA, SC, SD, SE, SG, SK, SL, SM, ST, SV, SY, TH, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, ZW. (84) Designated States (unless otherwise indicated, for every kind of regional protection available) : ARIPO (BW, GH, GM, KE, LR, LS, MW, MZ, NA, RW, SD, SL, ST, SZ, TZ, UG, ZM, ZW), Eurasian (AM, AZ, BY, KG, KZ, RU, TJ, TM), European (AL, AT, BE, BG, CH, CY, CZ, DE, DK, EE, ES, FI, FR, GB, GR, HR, HU, IE, IS, IT, LT, LU, LV, MC, MK, MT, NL, NO, PL, PT, RO, RS, SE, SI, SK, SM, (54) Title: EXTENDED RELEASE COMPOSITIONS AND PROCESS FOR PREPARATION (57) Abstract: The present invention relates to multiple unit extended release pharmaceutical compositions comprising plurality of modified release units wherein each unit comprises of an active agent core comprising at least one pharmaceutically active agent and at least one pharmaceutically acceptable excipient substantially coated with at least one release-controlling agent. The present invention also relates to a process for the preparation of these multiple unit extended release pharmaceutical compositions. EXTENDED RELEASE COMPOSITIONS AND PROCESS FOR PREPARATION Field of the Invention The present invention relates to multiple unit, extended release pharmaceutical compositions and the process for their preparation. Particularly the extended release compositions comprise plurality of modified release units, with each unit comprising an active agent core substantially coated with at least one release controlling agent. The active agent core comprises at least one pharmaceutically active agent and at least one pharmaceutically acceptable excipient. The invention further relates to preparation of such extended release formulations in the form of tablets, capsules, mini-tablets, orally disintegrating tablets, granules, dispersible tablets, and the like. Background of the Invention The concept of extended release formulations was developed to reduce the number of daily drug administrations, particularly for those drugs requiring reasonably constant blood levels over a long period of time and to improve patient compliance. Extended release compositions have also been designed to reduce incidences of adverse drug reactions by providing reduced fluctuations in the concentrations of the drug in the plasma. Extended release formulations have been adopted for those drugs that need to be administered at high doses, but are likely to cause undesirable side effects by a fast release of the drug. Amongst various formulation approaches available towards extending the release of active agents, the development of multiple unit systems in which each individual unit is formulated with modified release characteristics, has unique advantages. Multiple unit dosage forms possess a large surface area, which advantageously promotes complete and uniform absorption, minimizes peak plasma fluctuations and thus reduces the potential for systemic side effects. A further advantage of these dosage forms is that high local concentrations of the active substance in the gastrointestinal system is avoided as a consequence of the units being distributed freely throughout the tract. Additionally, the chances of dose dumping likely with certain actives and systems is also minimized with the multiple unit systems. Hence, the multiple unit dosage form ensures appropriate release of the active agent, resulting in a decreased dosing frequency and consequently better patient compliance. Formulation of drugs in multiple-unit dosage forms with units filled in capsules or compressed into tablets, offers flexibility to provide desired drug release properties. Multiple unit systems, also referred to as multiple unit pellet systems (MUPS) are usually prepared by the process of drug layering wherein the modified release units are prepared by coating inert beads or spheres, followed by coating with release rate controlling polymers. Numerous marketed products are based on this approach. Some examples include, metoprolol succinate (Toprol-XL® tablet), cyclobenzaprine hydrochloride (Amrix® E.R. capsules), fluvoxamine maleate (Luvox® E.R. capsule); tolterodine tartrate (Detrol® LA E.R. capsule). The currently marketed extended release dosage form of metoprolol succinate Toprol-XL® tablet, for example, a multiparticulate tablet dosage form comprises silicon dioxide beads as an inert core coated with active agent and release rate controlling polymers. Various patents and patent applications have also been filed for extended release formulations of metoprolol succinate based on this layering concept. U.S. Patent No. 8,815,285 discloses an extended dosage form of metoprolol or a salt comprising an inert core, wherein inert core is coated with a drug coat comprising metoprolol or a salt thereof and optionally other pharmaceutically acceptable excipients, said drug coat optionally being further coated with one or more pharmaceutically acceptable release rate-controlling polymers. U.S. Patent No. 4,957,745 discloses controlled release preparation containing a number of beads comprising a salt of metoprolol as the main soluble component, and a method for the production thereof. The beads may contain metoprolol alone or may consist of insoluble cores coated with metoprolol. Examples of insoluble cores are silicon dioxide and small particles of glass. U.S. Patent Application No. 20070202172 discloses an extended release tablet comprising metoprolol succinate pellets and pharmaceutically acceptable excipients, each pellet comprising an inert core, a drug layer and a rate controlling film coating. U.S. Patent No. 4,927,640 describes controlled release beads having glass or silicon dioxide core, metoprolol succinate sprayed on to the cores of silicon dioxide, glass or sodium chloride from a solution of ethanol 95% and methylene chloride. Then, the coated beads are filled into hard gelatin capsules. The drug layering approach however requires specialized equipment and is time consuming. It also results in batch to batch assay variations and uniformity issues. Drug layering approach is also associated with long production cycle times and scale-up concerns due to the complex and tedious nature of the drug layering process. Further with the conventional drug layering approach, large amounts of cushioning granules are often required to compress the coated drug layered pellets without causing any rupturing of the release controlling coats. This not only results in increased tablet weight and size but could also cause potential blend segregation during the manufacturing operations due to differences in the physical nature of the conventional drug layered pellets and cushioning granules. A need therefore exists to have a multiple unit system that is simple, robust, economical and less time consuming to manufacture. Such a system should not require specialized equipment and should provide greater assurance of uniformity, scalability and commercial viability. Such a system should also reduce batch to batch variability while providing the desired extended drug release profile. The present inventors after excessive efforts and experimentation have developed the extended release pharmaceutical formulations that address such a need and eliminate the drawbacks associated with the conventional multiple unit systems involving drug layering. The present invention provides multiple unit extended release system that avoids the tedious and time- consuming step of drug layering and thereby provides formulations with reduced batch to batch assay variations. The systems of the present invention prevent process loss of active and minimize the production cycle times when compared to the