Sr. No.

Patent Number

Type of Formulation

Salient feature

Year of publication

Reference

1

US20070134315A1

Extended release pellet and tablet formulations of isovaleramide

The patent application discloses extended release formulations of isovaleramide prepared using direct compression in which a sealing coating between said inner core and said rate controlling polymer system. Rate controlling polymer system is selected from the group consisting of ammonio methacrylate copolymer, cellulose derivatives, polyvinyl acetate, and derivatives thereof. It is used to effectively treat a variety of pathological conditions such as CNS disorders.

2007

[9]

2

US7674479B2

Sustained-release bupropion hydrochloride pharmaceutical tablets

This reference discloses sustained-release tablet containing sustained release granules of bupropion hydrochloride admixed with a hydroxyalkylcellulose and an extragranular phase comprising a particulate material that provides a sustained release matrix; said particulate material is selected from the group consisting of polyvinylacetate, blends of polyvinylacetate and polyvinylpyrrolidone etc. which then is coated, with a means to provide delayed release, such as with an enteric coating composition.

2010

[14]

3

US20100278918A1

Extended release  composition particularly tablet comprising nevirapine

Patent application discloses extended release tablet dosage form containing nevirapine and Hypromellose 2208 (Methocel™ K4M Premium CR) for treatment of HIV infection; wherein each tablet is compressed by a force of 10-25 kN.

In-vitro dissolution profile: at least 2% w/w and no more than 30% w/w of the nevirapine is released at 2 hours; at least 20% w/w and up to 100% w/w of the nevirapine is released at 8 hours; at least 40% w/w and up to 100% w/w of the nevirapine is released at 14 hours, when dissolution is measured by the USP Paddle Method at 50 rpm at a volume of 900 mL aqueous buffer containing 6% w/w of sodium lauryl sulfate, having a pH of 6.8 at 37° C.

2010

[15]

4

US20100144800A1

An extended release tablet comprising niacin

It discloses extended release tablet containing niacin and release retarding agent selected from hydroxypropyl cellulose, polyethylene oxide or mixtures thereof. It can be prepared by wet granulation, dry granulation or direct compression process.

2010

[16]

5

US20100247646A1

An extended release tablet containing nisoldipine

This patent application discloses extended release tablets containing a core having nisoldipine, a rate-controlling hydrophilic polymer and optionally, an enteric agent. These tablets may also be coated with a release rate-controlling coating comprising of a hydrophobic polymer or enteric agent or combinations thereof, in particular ethylcellulose, and Eudragits.Tablet coating also contains a channel forming agent.

2010

[17]

6

US7776358B2

An extended release coated pharmaceutical tablet

This patent discloses extended release coated pharmaceutical tablet containing core formed of Venlafaxine besylate as active agent and lipophilic matrix material and coating over tablet core containing an ammonio methacrylate copolymer component.
 Dissolution profile:
 Time Venlafaxine 2 hours <30% 4 hours 30-55% 8 hours 55-80% 12 hours  65-90% 24 hours >80% in USP 2 apparatus using SGF, pH 1.2, medium for hours 0-2 and then SIF, pH 6.8, medium for hours 2-24.

2010

[18]

7

US7695734B2

An extended release tablet comprising pramipexole

An extended release tablet formulation prepared using direct compression comprising pramipexole in a matrix comprising at least two water swelling hydrophilic polymers wherein at least one of the at least two polymers is an anionic polymer and the other is a substantially neutral polymer.

 The resulting tablet formulation provids a pH-dependent release rate in the range of pH<4.5, and a pH-independent release rate in the range from pH 4.5 to 7.5, wherein the release rate in the range of pH<4.5 is higher than the release rate in the range from pH 4.5 to 7.5.

2010

[19]

8

US7863316B2

Extended release tablet of levetiracetam

This patent discloses ER tablet containing levetiracetam and water dispersible rate controlling polymer selected from HEC, HPC, sodium alginate, carbomer, sodium carboxymethyl cellulose, xanthan gum, guar gum, locust bean gum, poly vinyl acetate, polyvinyl alcohol and HPMC which is prepared by wet granulation, dry granulation or direct compression and the core is coated either in a coating pan or in a fluidized bed system.

Tablet exhibiting a value of (AUCfed)/(AUCfasted) of at least 0.80 with a lower 90% confidence limit of at least 0.75. Also, the composition exhibits no food effect.

2011

[7]

9

US20110033536A1

Extended-release pharmaceutical composition of metoclopramide hydrochloride

This patent application discloses extended release composition containing hydrophilic, hydrophobic polymers as well as hydrophilic component which promote water penetration within the tablet. Tablet is administered for treatment or prevention of disorders such as vomiting, esophageal gastric reflux and nausea.

Mechanism: The hydrophobic polymer shows plastic deformation properties under compression, tending to surround the drug substance particles reducing the pore quantity and dimensions in the matrix structure, delaying as a consequence the drug substance release. The hydrophilic component is part of the gel coating structure providing support.

2011

[13]

10

US8039009B2

Modified release solid oral dosage form

Patent discloses modified release solid oral dosage form for the treatment of Alzheimer's disease containing memantine and polymeric carrier substantially contributing to the modification of the release of the memantine. Polymeric carrier is a polymeric matrix is a swellable matrix and comprises hydroxypropyl methylcellulose.
 The dissolution rate of more than about 80% is achieved after about 12 hours and dosage form provides a Tmax of more than 10 hours.

2011

[20]

11

US20110262537A1

An extended release tablet

This patent application discloses an extended release tablet containing an inner tablet of ropinirole with one or more rate controlling polymers. The rate controlling polymers are selected from one or more of gums or its derivatives, polyuronic acid salts or its derivatives, cellulosic polymers or its derivatives, acrylic acid polymers or its derivatives and waxes.
 
 Dissolution profile: at least 5% of ropinirole is released within 1 hour; at least 10% of ropinirole is released within 2 hours; at least 35% of ropinirole is released within 6 hours; at least 5O% of ropinirole is released within 12 hours.

2011

[21]

12

US20110217373A1

Extended release tablet
 of guanfacine

This particular patent application discloses extended release tablet containing guanfacine and one or more of pH-independent rate controlling polymer( s)

2011

[22]

13

US20110052686A1

A modified-release uncoated tablet of lamotrigine

This patent application discloses multi-layer tablet containing
 (a) a first portion consisting of lamotrigine in an admixture with a pH-dependent polymer such as polyacrylic and polymethacrylic acids and polyacrylate and methacrylate based polymers etc; and
 (b) a second portion comprising the remaining amount of lamotrigine and a pH-independent polymer such as methylcellulose, ethylcellulose, hydroxymethyl cellulose, etc.
 In vitro dissolution profile when measured in a USP type II apparatus, at 50 rpm, at a temperature of 37° C.±0.5° C. in 900 mL of 0.1 N HCl medium:
 (i) at most about 35% drug released in 2 hours;
 (ii) at most about 55% drug released in 4 hours;
 (iii) at most about 80% drug released in 8 hours; and
 (iv) at least about 80% drug released in 16 hours.

2011

[23]

14

US20110027361A1

An extended release tablet or capsule containing Paliperidone

This patent application discloses extended release matrix composition containing Paliperidone and matrix agent is selected from a insoluble release controlling agent such as pH dependent polymer like Eudragit® FS 30D or pH independent polymer like Eudragit® RL 100, a hydrophilic release controlling agent such as hydroxyethyl cellulose or hydroxyl propyl methyl cellulose., a fatty release controlling agent.

2011

[24]

15

US20120219625A1

An extended-release tablet comprising Clarithromycin

This patent application discloses an extended-release tablet containing Clarithromycin, a water soluble diluent and an acidic compound chosen from potassium bitartrate, sodium bitartrate and monosodium citrate; wherein the acidic compound is operable to increase a rate of dissolution of Clarithromycin. Tablet comprises a film coating surrounding the tablet.
 The tablet is free from polymers or contains polymer that is insufficient to function as a release controlling agent.
 Disclosed tablet exhibits dissolution from about 50% to about 80% at 6 hours.

2012

[25]

16

US20120201886A1

A non-osmotic coated extended release composition specifically tablet

This patent application discloses non-osmotic coated extended release composition with core containing Paliperidone with one or more pharmaceutical excipients wherein the core is coated with a release controlling composition comprising one or more hydrophobic agents and one or more hydrophilic agents.
 Tablet is prepared using direct compression, dry granulation, wet granulation (aqueous/non-aqueous or combination) or melt granulation.

2012

[26]

17

US20120058183A1

Tablets with modified release containing retigabine

This patent application discloses tablet containing retigabine, water-soluble excipient, and a non-water-soluble excipient wherein, use of a combination of water-soluble and non-water-soluble excipients provides modified release The tablet contains 1 to 45% by weight of the amount of active agent as an initial dose for immediate release and 55 to 99% of the amount of active agent is present as a matrix formulation for delayed release.

2012

[27]

18

US8309122B2

An analgesically effective controlled release tablet

This patent discloses controlled release tablet with a twelve hour dosing interval containing Oxymorphone wherein the controlled release delivery system comprises a hydrophilic material that forms a gel upon exposure to gastrointestinal fluid. System further comprises a hydrophobic polymer such as alkylcellulose.

Specifically, controlled release delivery system comprises a heteropolysaccharide such as xanthan gum or deacylated xanthan gum and an agent capable of cross-linking the heteropolysaccharide such as locust bean gum in presence of gastrointestinal fluid.

2012

[28]

19

US20130034604A1

An extended release monolithic tablet

This patent application discloses ER tablet containing Desvenlafaxine and release controlling agent selected from water soluble/swellable polymers such as hydroxypropyl methylcellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, sodium carboxymethyl cellulose, xanthan gum, karaya gum, locust bean gum, alginic acid, sodium alginate, polyvinyl alcohol, polyvinylpyrrolidone or mixtures thereof and prepared using dry/wet granulation technique.

2013

[29]

20

US8343544B2

Oral sustained-release tablet

The patent discloses oral sustained-release tablet containing 4-(2-methyl-1-imidazolyl)-2,2-diphenylbutylamide (KRP-197) as active agent and hydroxypropylmethylcellulose which is used for the treatment for increased urinary frequency and urinary incontinence.

2013

[30]

21

US8399016B2

Sustained-release tablet composition of pramipexole

Patent discloses sustained-release tablet used to treat Parkinson's disease or a complication associated therewith containing core comprising pramipexole dispersed in a matrix comprising 

(a) hydroxypropylmethylcellulose and (b) a pregelatinized starch having a tensile strength of at least about 0.15 kN cm−2 , core being substantially enclosed in a coating comprising an ethylcellulose-based hydrophobic or water-insoluble component and an HPMC-based pore-forming component.
 The hydrophilic polymer functions to provide extended or sustained release of the pramipexole, for example by gradual dissolution or erosion of the polymer in the gastrointestinal tract.

2013

[31]

22

US8545886B2

Extended release system in the form of a tablet or bilayer tablet

This particular patent discloses extended release system containing active substance with pH-dependent water solubility such as flibanserin, pH-dependent polymers and pH-independent polymers using process such as wet granulation, direct compression or roller compaction

2013

[8]

23

US8778417B2

Sustained-release tablet of elemene

Sustained-release tablet is obtained containing elemene as an anti-tumor active agent, more specifically mixture of β-elemene, gamma-elemene and delta-elemene, or is a β-elemene monomer and sustained-release agent is chosen from hydroxypropyl methyl cellulose, polyvinyl pyrollidone, ethylcellulose, methyl cellulose, hydroxyethyl cellulose, sodium carboxymethyl cellulose.

2014

[32]

24

US8865778B2

A slow or extended release tablet formulation

This patent discloses extended release tablet containing synergistic mixture of substantially uncross-linked carboxymethyl starch, or sodium starch glycolate (SSG), and hydroxypropylmethylcellulose and active ingredient
 Mechanism: Water or gastrointestinal fluid first hydrates the polymers at the surface of the tablet and the hydrated polymers form a viscous gelled outer layer to the tablet. This layer contains not only the polymers but also all the other formulation components including the active ingredient. 

2014

[12]

25

US20140335175A1

An extended release tablet formulation comprising pramipexole

It discloses an extended release tablet formulation tablets manufactured via a direct compression process comprising pramipexole in a matrix comprising one water swelling polymer. The water swelling polymer is an anionic polymer such as acrylic acid polymerisate, methacrylic acid copolymers, alginates, carrageenans, acacia, xanthan gum, chitin derivates, carmellose sodium and carmellose calcium.
 The resulting tablet provided a pH-independent in vitro release characteristic in the range from pH 1 to 7.5, or the resulting tablet providing a pH-dependent release characteristic with a faster release characteristic in the range of pH<4.5, and a slower and further on pH-independent release characteristic in the range from pH 4.5 to 7.5.

2014

[33]

26

US8771732B2

An oral sustained release formulation specifically tablet, powder or capsule of nalbuphine

An oral sustained release formulation as analgesic comprising nalbuphine homogeneously dispersed within a hydrophilic gel matrix wherein the hydrophilic gel matrix comprises xanthan gum, a hydrophilic cellulose ether (hydroxypropylcellulose/ hydroxypropylmethylcellulose) or both.
 The solid dosage form wherein 75%-100% of the nalbuphine or a pharmaceutically acceptable salt thereof is released after about 12 hours as determined using USP Apparatus III at 15 dpm in a pH 6.8 buffer at 37° C.

2014

[34]

27

US20150283084A1

Disintegrating monolithic modified release tablets containing sustained release granules

This patent application discloses modified release formulation containing sustained release granules which comprises overlubricated drug particles which contain a core particle comprising a drug; and a hydrophobic adherent layer deposited over at least a portion of the core particle and hydrophobic binding layer, wherein the one or more overlubricated drug particles are suspended in the hydrophobic binding material; and
 a disintegrant layer deposited over the hydrophobic binding layer of the agglomerated drug particle. Tablets are prepared by over-mixing and hot melt granulation. Active agent in the core comprises amoxicillin, potassium clavulanate. 

2015

[11]

28

US9050335B1

Extended release tablet containing oxycodone and acetaminophen

Extended release pharmaceutical compositions comprising oxycodone and acetaminophen that produce a quick initial onset of analgesia, yet, maintain analgesia for about 12 hours after administration of the composition extended release component comprises extended release polymer such as polyethylene oxide.

2015

[35]

29

US9180104B2

12-hour anti-tussive modified release tablet or capsule

It discloses modified release solid oral composition containing a. solid dispersion of benzonatate and modified release pH-independent, hydrophilic or hydrophobic matrix-forming substance and b. a reverse enteric coating over the homogenous solid dispersion. Matrix-forming substance contains hydrophilic polymer such as hydroxypropyl methylcellulose and hydrophobic modified release wax or waxy substance such as glyceryl behenate. Reverse enteric coating comprises (a) a pH-dependent methyl methacrylate and diethylaminoethyl methacrylate copolymer or (b) a pH-dependent cationic copolymer based on dimethylaminoethyl methacrylate, butyl methacrylate and methyl methacrylate.

2015

[36]

30

US9636305B2

Antiemetic extended release tablet

It discloses ondansetron tablet containing a monolithic core comprising hypromellose and ondansetron dispersed within the hypromellose, and sodium citrate anhydrous dispersed within the hypromellose. The sodium citrate anhydrous allows it to form a hardened boundary around the periphery of the hypromellose upon exposure to an aqueous medium so as to limit the rate at which the ondansetron is released from the core.
 This tablet yields a burst of approximately 25% ondansetron followed by a zero-order sustained release of ondansetron, and total amount of ondansetron is released over 24 hours.

2017

[37]

31

US9545399B2

An extended release racemic methylphenidate chewable tablet

The tablet contains a combination of an uncoated methylphenidate-ion exchange resin complex, a barrier coated methylphenidate-ion exchange resin complex-matrix, and an uncomplexed methylphenidate active component.
 Following the administration of a single dose of the prepared tablet, a therapeutically effective amount of methylphenidate is reached in less than about 20 minutes and the composition provides a twelve-hour extended release profile.

2017

[38]

32

US20180116967A1

A directly compressed extended release cyclobenzaprine tablet

This patent application discloses a directly compressed extended release cyclobenzaprine tablet using hydroxypropyl methylcellulose (HPMC) for treating a skeletal muscle disease or condition.
 Dissolution testing studies in which the % of cyclobenzaprine released from the tablet at 2 hours ranges from 30% to 45%, the % of cyclobenzaprine released from the tablet at 4 hours ranges from 45% to 70%, and the % of cyclobenzaprine released from the tablet at 8 hours is more than 65% in 900 mL of 0.1N HCl at 37°C. and a rotation speed of 50 rpm using USP apparatus I.

2018

[6]

33

US10172797B2

Oral, extended release abuse deterrent pill 

This patent discloses an oral, extended release, abuse deterrent pill containing oxymorphone HCl and controlled release agent selected from either HPMC or combination of PVA and PVP prepared using a hot melt extrusion process. This pill exhibits less than 10% increase in the release of the oxymorphone HCl or pharmaceutically acceptable salt thereof in a simulated alcoholic gastric fluid environment

2019

[10]

34

US20200188378A1

Methylphenidate extended release chewable tablet

This particular patent application discloses extended release chewable tablet containing a sustained release methylphenidate component comprising water-insoluble, water-permeable, pH-independent barrier coated, methylphenidate-ion exchange resin complex in a polymeric matrix. Chewable tablet is capable of being divided and providing tablet portions which retain a therapeutically effective immediate release and 12 hour extended release profile.

2020

[39]

35

US10624888B2

Extended release abuse deterrent tablet or capsules 

This patent discloses extended release, abuse deterrent dosage form having plurality of particles consists of a blend of polyvinyl acetate and polyvinylpyrrolidone, an optional polyethylene oxide and active agent chosen from oxycodone, oxymorphone, hydrocodone, hydromorphone, codeine, morphine preprared using hot melt extrusion process.

2020

[40]

Sr. No.

Patent Number

Type of Formulation

Salient features

Year of publication

Reference

1

US7270831B2

Capsule containing sustained release beads and the immediate release beads

It discloses oral analgesic dosage form for once-a-day administration as multiparticulate systems containing (a) sustained release beads comprising sugar beads, a coating comprising morphine sulphate on the sugar beads and an overcoating comprising one or more ammonio methacrylate copolymers; and (b) immediate release beads comprising sugar beads and a coating comprising morphine sulphate on the sugar beads

2007

[41]

2

US7476403B2

The controlled release dosage form in the form of capsule filled with tablet or caplet

A controlled release dosage form containing clarithromycin, polymer having a viscosity less than 50 cps such as hydroxypropyl cellulose or hydroxypropyl methylcellulose and polymer, having a viscosity greater than 200 cps such as hydroxypropyl cellulose or hydroxypropyl methylcellulose. Dosage form provides therapeutic effect for at least 12 hours and does not exhibit an in vivo food effect.

2009

[42]

3

US20110123610A1

An extended release hard gelatin capsule with a therapeutically effective
 number of mini tablets

This patent application discloses an extended release hard gelatin capsule containing therapeutically effective number of mini tablets, mini tablets contains: Tolterodine incorporated in a hydrophobic matrix comprising water insoluble polymer and wax which controls release of active agent. Tablet is prepared using technique such as direct compression, dry granulation, wet granulation or melt granulation.

2011

[43]

4

US8889190B2

Extended-release topiramate capsules

This patent discloses extended-release capsule dosed once daily to patients suffering from epilepsy which contains a capsule shell comprising coated particles which contains core containing topiramate and a coating, wherein the coating contains release controlling agent(s) such as ethylcellulose, polyvinyl acetate, polyacrylate and polymethacrylate, copolymers thereof which provide extended release. Capsule shell is made up of hydroxypropyl methylcellulose 

2014

[45]

5

US20170056342A1

An extended-release composition of cyclobenzaprine for oral administration in the form of a capsule containing one or more tablets

This patent application discloses an extended-release composition of cyclobenzaprine in the form of a capsule containing one or more tablets, wherein each of the tablet is a matrix-type tablet containing cyclobenzaprine. Polymer used to prepare tablet is one of water-insoluble and an enteric polymer specifically hydroxypropyl methylcellulose acetate succinate.

Dissolution studies: using USP Apparatus #2, complies with the following specifications: (1) after 2 hours in 900 mL of 0.1 N HCl, at 37° C. at 50 rpm, no more than about 40% of the cyclobenzaprine is released; and (2) after 8 hours in 900 mL of 0.05 M phosphate buffer at pH 6.5, 37° C. and 75 rpm, at least about 60% of the cyclobenzaprine is released.

2017

[46]

6

US9555005B2

Extended-release topiramate capsules

This patent discloses capsule containing capsule shell comprising coated particles in which each coated particle comprises a core and a coating thereon, core contains a homogeneous mixture of topiramate and other excipients and coating contains  release controlling agent(s) such as ethylcellulose, polyvinyl acetate, polyacrylate and polymethacrylate.
 Topiramate capsule when dosed once daily, achieves at steady-state, an AUC0-24h, Cmax, and Cmin in the subject's plasma that are within the 80% to 125% bioequivalence criteria compared to immediate-release topiramate dosed at the same total daily dose divided twice per day.

2017

[47]

7

US20180344653A1

An extended release multiparticulate composition comprising a plurality of discrete units filled into a capsule or a sachet

This patent applicationdiscloses extended release multiparticulate composition for the treatment of angina which contains a plurality of discrete units such as pellets, granules, minitablets and beads which contains a) a drug layered core comprising ranolazineb) an extended release coating comprising a water-insoluble polymer and a pH-dependent polymer. The composition releases about 15% to about 40% of the ranolazine in an initial 2 hours in 900 ml 0.1N HCl and releases about 60% to about 90% of the ranolazine in 6 hours in 900 ml pH 6.8 phosphate buffer; when measured in United States Pharmacopoeia (USP) type II dissolution apparatus, rotating at 50 rpm at a temperature of 37° C.

2018

[44]

8

US20200054573A1

Extended release composition in the form of once-a-day capsule filled with multiparticulates

This patent application discloses extended release pharmaceutical composition of Clozapine in the form of multiparticulates such as granules, pellets, beads, spheroids in which Clozapine is first coated with a seal coat, then an acidic coat which contains osmotic agent and an extended release coat. Extended release coating is of ethyl cellulose and polyethylene glycol. 

2020

[48]

Sr. No.

Patent Number

Type of Formulation

Salient features

Year of publication

Reference

1

US20050169991A1

A sustained release oral dosage form sometimes     bi-layer tablet 

This patent application discloses sustained release oral dosage form containing an effective amount of torsemide and a sustained release excipientwhich is selected from the group consisting of a gelling agent, a cellulose ether, an acrylic resin, a protein derived material, a wax, shellac, a sustained release polymer, oil, and mixtures thereof.
 In-vitro dissolution studies: sustained release dosage form providing dissolution rate when measured by USP 26 (2003) dissolution Apparatus type III, in pH change media with an agitation of 15 dpm in 250 ml and at 37° C. which is from 0 to about 50% torsemide released after 1 hour; from about 1 to about 60% torsemide released after 3 hours; from about 5 to about 70% torsemide released after 7 hours; from about 10 to about 95% torsemide released after 12 hours

2005

[53]

2

US7303761B2

A pharmaceutical composition specifically capsule having
 an extended-release first portion containing NSAIDs

It discloses a pharmaceutical composition for the treatment of inflammatory condition or disease such as osteoarthritis or rheumatoid arthritis containing

 a. an extended-release first portion containing therapeutically effective amounts of NSAIDs mixed with at least one retardant material for extended release delivery presenting a controlled availability of NSAIDs alongside the gastrointestinal tract and
 b. an immediate release second portion made of a powder a stabilized misoprostol. Both portions are encapsulated within a capsule made of hydroxyl-propyl-methyl-cellulose (HPMC) polymer. Retardant material of the first portion is selected from the group consisting of lipidic materials, acrylic and methacrylic acid polymers and copolymers, alkyl celluloses, gums, protein derived materials and a mixture thereof.

2007

[54]

3

US7682632B2

oral dosage form with controlled release opioid analgesic

This patent discloses a dosage form having particles containing (a) an opioid antagonist; (b) hydrophobic means for sequestering the opioid antagonist such as acrylic polymer.

Dissolution studies: The ratio of the amount of antagonist released from the dosage form after tampering to the amount of the antagonist released from the intact dosage form is about 4:1 or greater, based on the in-vitro dissolution at 1 hour of the dosage form in 900 ml of Simulated Gastric Fluid using a USP Type II (paddle) apparatus at 75 rpm at 37° C.

2010

[55]

4

US8231904B2

A two-layer extended release tablet for the oral administration of pralnacasan

It discloses atwo-layer extended release tablet containing rapid release layer comprising pralnacasan and croscarmellose as a disintegrant, and an extended release layer comprising pralnacasan and hydroxypropylmethylcellulose as a gel former
 At least 60% of the pralnacasan is released from the tablet not more than 30 minutes after administration, and at least 90% is released not more than 180 minutes after administration.
 It is suitable for the treatment of autoimmune diseases, type I and type II diabetes, rheumatoid arthritis, osteoarthritis or psoriasis

2012

[56]

5

US8313768B2

Tablet comprises both an immediate release region and a modified release region

This patent discloses tablet containing both an immediate release region and a modified release region, and its method of preparation is: (a) forming a tablet shape comprising a powder blend comprising active agent and a thermally-sensitive material; and (b) applying energy in different amounts to different regions of the surface of the tablet shape to form said tablet in a manner such that: (i) a first region of said tablet shape is exposed to said energy for a sufficient period of time to modify said thermally-sensitive material within said first region to form said modified release region of said tablet; and (ii) a second region of said tablet shape is not so exposed to said energy such that said second region forms said immediate release region of said tablet.

Tablet releases from about 1 to 50 percent is released in the 60 minutes following oral ingestion and about 50 to 99 percent is released from about 60 minutes to about 24 hours after oral ingestion.

2012

[50]

6

US20120064159A1

Multilayer tablet having immediate release layer and extended release layer

This patent application disclosesa multilayer tablet having (a) an immediate release layer containing NSAID & acetaminophen and a substituted alkylcellulose; and (b) an extended release layer containing a NSAID and/or acetaminophen, waxand alkylcellulose or

a substituted alkylcellulose

In-vitro dissolution studies: the NSAID and/or acetaminophen release rate from the tablet, when measured in vitro using a USP type II dissolution apparatus (paddle) in phosphate buffer at pH 6.8 and at 75 rotations per minute, corresponds to a dissolution pattern of: a) from 20 to 70% of the total NSAID and/or acetaminophen is released after 1 hour     b) not less than 50% of the total NSAID and/or acetaminophen is released after 3 hours and c) not less than 70% of the total NSAID and/or acetaminophen is released after a total of 6 hours

2012

[57]

7

US20120321713A1

Gastric retentive extended-release dosage forms

It discloses the dosage form comprising a dose of acetaminophen and a dose of an opioid, wherein the dosage form comprises an extended release matrix that imbibes fluid after administration and swells to a size sufficient to promote gastric retention of the matrix and a method for treating pain using same,  

Disintegration studies: within about 1 hour in an in vitro disintegration test the dosage form releases more than about 50% of the dose of acetaminophen, and wherein by about 6 hours in an in vitro disintegration test, the percent of opioid released from the dosage form is greater than the percent of acetaminophen released from the dosage form, and wherein the in vitro disintegration test is a USP type II apparatus at 37° C. in 0.1 N HCl.

2012

[58]

8

US8535715B2

A bilayer tablet having layer of metformin extended release formulation … 

This patent discloses a bilayer tablet used for the treatment of diabetes, impaired glucose tolerance, insulin resistance, hyperglycemia and hyperinsulinemia contains (1) first layer is a metformin extended release formulation comprising about metformin hydrochloride (HCl) in an  sodium carboxymethyl cellulose,  hydroxypropyl methylcellulose, and other excipients (2) second layer is a sodium-dependent glucose transporter (SGLT2) inhibitor formulation having of an SGLT2 inhibitor selected from dapagliflozin, lactose anhydrous, microcrystalline cellulose, pregelatinized starch, and other excipients ; and(3) optionally a film coating that covers the first layer and the second layer

2013

[59]

9

US8563034B2

A dual release oral tablet of dexlansoprazole

This patent discloses a dual release oral tablet for use in the treatment of gastrointestinal disorders contains a) dexlansoprazole in powder form; b)dexlansoprazole in granule form, hydrophobic agents, c) a single enteric coating that dissolves at between pH 5.5 and 6.4 The hydrophobic agents are selected from hydrogenated vegetable oils, wax, wax-like substance, fats, oils, fatty acid, fatty alcohol, shellac, pullulan, agar, gellan gum, guar gum, carageenan, acacia gum, gum arabic, dextran, pectin etc. and single enteric coating that dissolves at between pH 5.5 and 6.4 comprises cellulose acetate phthalate, cellulose acetate

2013

[60]

10

US8685451B2

Multi-layered tablet for a triple combination release of active agents 

This patent discloses combination release tablet having a) a drug-containing rapid release first compressed composition comprising of drug selected from the group consisting of levodopa, carbidopa, ondansetron, quetiapine and ergotamine and excipients; b) a drug-containing extended release second compressed composition comprising a release rate modifier extended release polymer, and at least one drug selected from the group consisting of levodopa, alprazolam, quetiapine, divalproex and naproxen; and c) an osmotic device comprising a drug-containing core, the core being surrounded by a membrane comprising cellulose ester and plasticizer and having a preformed passageway through it

2014

[61]

11

US8758818B2

A dual release oral tablet having a gradual release

This patent discloses a dual release oral tablet having a gradual release for use in the treatment of gastrointestinal disorders which contains a) dexlansoprazole in powder form;b) dexlansoprazole in granule form comprising the dexlansoprazole, lactose, and microcrystalline cellulose; andc) a single enteric coating that dissolves at between pH 5.5 and 6.4 Upon oral administration, the tablet achieves dual release of the dexlansoprazole in that the dexlansoprazole is released in the small intestine at pH 5.5, and then at pH 6.0 to 6.5, with prevention of dose dumping of the dexlansoprazole.

2014

[52]

12

US2020222401A1

Fixed combination of rosuvastatin and metformin solid dosage product  specifically bi-layer formulation

This particular patent application discloses fixed combination of rosuvastatin and metformin solid dosage product more particularly as bi-layer tablet prepared by compressionsuch that rosuvastatin is delivered immediately to the patient and metformin is delivered in a controlled fashion over a longer course of time. For prolonged delivery of metformin, it is provided in granules comprising cellulose, a polymer, water and organically soluble cellulose (hydroxypropyl cellulose).
 This fixed combination tablet is used for treatment of hyperlipidemia, simultaneously with type 2 diabetes

2020

[62]

13

US10632077B2

Oral sustained-release triple layer tablet containing Pregabalin
 gastro-retentive sustained-release preparation

This patent discloses a multilayer tablet having an upper layer and a lower layer comprising a swellable polymer; and an intermediate layer comprising a medium transfer agent, all 3 layers contain pregabalin
 medium transfer agent is hydrophillic and is selected from sugars, polyvinylpyrrolidone, salts, organic acids, starch, microcrystalline cellulose, and low-substituted hydroxypropylcelluloses which absorbs the aqueous medium and transfers it to the upper layer and the lower layer.

2020

[51]

Sr. No.

Patent Number

Type of Formulation

Salient features

Year of publication

Reference

1

WO2007078895

Once daily controlled-release  osmotic dosage form comprising tramadol

This patent application discloses first once daily controlled-release dosage form containing tramadol and means for controllably releasing the tramadol having at least one swellable and erodible matrix core. The means for- controllably-releasing-the-tramadol also contains at least one release-slowing coat, which contains at least one pH independent polymer, pH dependent polymer, soluble polymer, insoluble polymer or swellable polymer.
 Controlled-release dosage form exhibits an in- vitro release rate such that after about 2 hours from about 0 to about 22% by weight of tramadol is released, after about 4 hours from about 5 to '* about 30% by weight of tramadol is released, after about 6 hours, from about 15 to about 38% by weight of tramadol is released, and after about 8 hours

2007

[66]

2

US8329217B2

A dual controlled release osmotic device

Patent discloses a dual controlled release osmotic device containing a) a core comprising a first active agent-containing controlled release layer and a second active agent-containing controlled release layer in direct contact therewith, wherein the second active agent-containing layer surrounds the first active agent-containing layer; and the osmotic device excludes a push-layer b) a membrane surrounding the core, wherein the membrane comprises at least one preformed passageway in communication with at least one of the first and second active agent-containing controlled release layers. 

From osmotic device each drug is independently released according to a timed, targeted, pseudo-first order, first order, pseudo-zero order, zero-order, and/or delayed release profile and the first and second release profiles are different.

2012

[65]

3

US10172842B2

A sustained release oral osmotic tablet

Patent discloses sustained release oral osmotic tablet containing a drug compartment comprising dalfampridine, sodium chloride, HPMC; a push compartment, comprising sodium chloride, HPMC;
 a semipermeable membrane, coating on said tablet core and at least one passageway through said semipermeable membrane to said tablet core.  

It is used for treating spinal cord injury, Alzheimer's disease, multiple sclerosis, amyotrophic lateral sclerosis or post-stroke deficiency. 

Fluctuation index of osmotic tablet is not more than 1.5 and exhibits the following dissolution profile when placed in a USP type II apparatus in about 500 mL of purified water at about 37° C.: 

between 18.95% to 29.27% of said dalfampridine is released in 4 hours; 

between 45.62% to 52.90% of said dalfampridine is released in 8 hours; and 

between 73.66% to 81.62% of said dalfampridine is released in 18 hours.

2019

[67]

Sr. No.

Patent Number

Type of Formulation

Salient features

Year of publication

Reference

1

US20080050429A1

Extended-release matrix formulation containing Niacin

This patent application discloses extended-release matrix tablets which are effective in reducing a serum lipid and are prepared using direct compression contains niacin, a release-retarding agent and other excipients. The release-retarding agent is selected from the group consisting of hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC or hypromellose), methylcellulose (MC), hydroxyethyl cellulose (HEC), polyvinyl pyrrolidone (PVP) and xanthan gum, etc.

2008

[70]

2

US20140302138A1

An extended release matrix tablet for once daily administration comprising Carbamazepine

This patent application discloses an extended release composition for treating epilepsy and trigeminal neuralgia containing a. a matrix core comprising Carbamazepine and b. a coating comprising at least one hydrophobic release controlling agent and at least one hydrophilic release controlling agent.
 Core tablets of composition can be prepared by wet granulation, dry granulation, melt granulation etc.
 In-vitro dissolution studies: dissolution rate when measured using the USP Type I (Basket apparatus) at 100 rpm in 1800 mL, 0.1N hydrochloric acid for first 2 hours followed by the media with pH 6.8 phosphate buffer at 37° C.±0.5° C. is configured to release: a. from about 5 to about 25% Carbamazepine after 1 hour; 

b. from about 10 to about 45% Carbamazepine after 4 hours;
 c. from about 35 to about 70% Carbamazepine after 8 hours;
 d. from about 55 to about 78% Carbamazepine after 12 hours;
 e. from about 70 to about 78% Carbamazepine after 16 hours; or
 f. greater than 78% Carbamazepine after 24 hours.

2014

[71]

3

US20150231267A1

Extended release potassium citrate wax-matrix tablet 

This particular patent application discloses extended release matrix tablet containing potassium citrate as active agent and carnauba wax.

Matrix tablet is prepared by mixing potassium citrate and carnauba wax and heating to a temperature below the temperature at which carnauba wax liquefies.

2015

[69]

4

US20190374473A1

Gastro-retentive dosage form comprising an extended release portion and an immediate release portion

This patent application discloses gastro-retentive dosage form for the treatment of myasthenia gravis which contains: an extended release portion and an immediate release portion, wherein the extended release portion contains a core comprising pyridostigmine bromide, an acid, a gas-generating agent, and a water-soluble hydrophilic polymer that swells via imbibition of gastric fluid in about 60 minutes or less to a size that prevents its passage through the pyloric sphincter; and a permeable elastic membrane surrounding the core. 

From the dosage form, reduced initial burst release comprises an in vitro release of between about 20% and about 35% of the pyridostigmine bromide within 2 hours of dissolution in a dissolution medium comprising 50 mM acetate buffer with 100 mMNaCl and dosage form maintains its integrity in a swollen state for a period of at least about 14 hours and capable of providing an extended plasma concentration profile for up to about 24 hours.

2019

[72]

Sr. No.

Patent Number

Type of Formulation

Salient features

Year of publication

Reference

1

US9884021B2

Delayed release tablet containing prednisone

This patent discloses press coated delayed release tablet with defined core containing a pharmaceutically active agent , and a compression coating around said core which is disposed within said compression coating such that the coating thickness about an axis (X-Y) is thicker and less dense than the coating about an axis (A-B) orthogonal to (X-Y), wherein said compression coating is formed of a water insoluble or poorly water soluble hydrophobic material and said coating is sufficiently porous about the (X-Y) plane of the tablet to permit the ingress of aqueous media to the core at a rate to ensure the release of the active agent after a period of time between 2 to 6 hours wherein said period of time is followed by rupture of the coating along the X-Y axis, and active agent is a glucocorticosteroid selected from prednisone, prednisolone or methylprednisolone.

Dissolution studies: The tablet has an in vitro dissolution profile using USP dissolution apparatus No. 2 at a stirring rate of 100 rpm and in a dissolution medium of 500 ml of purified water such that there is a median lag time of about 4 hours and at least 80% of active is released after 4.5 hours and about 100% of the active is released after 5 hours.

2018

[73]

2

US20190125682A1

Tablets that exhibit delayed release properties

This patent application discloses tablets that exhibit delayed release properties for the treatment of a neurodegenerative disease containing (a) a core comprising the active pharmaceutical ingredient such as deferiprone and an enteric polymer which can be chosen from hydroxypropyl methylcellulose acetate succinate (HPMCAS), HPMC phthalate, polyvinyl acetate phthalate, methacrylic acid copolymers etc., and (b) an enteric coating.

Pharmacokinetic parameters: single dose of the tablet provides a mean AUC∞/Cmax ratio between 3.5 hours and 6.0 hours in fasted state and/or fed state

2019

[74]

3

US20190151246A1

A delayed-release tablet/capsule

This patent application discloses a delayed-release tablet/capsule for the treatment of attention deficit hyperactivity disorder containing
 (a) core comprising methylphenidate and (b) release-modifying layer which comprises the combination of an enteric polymer and a hydrophobic agent.

2019

[75]

4

US10675247B2

A press coated tablet for delayed release of an active ingredient

This patent discloses a press coated tablet for delayed release of an active ingredient which contains
 (a) a core comprising one or more active ingredients, and;
 (b) an erodible delayed release barrier surrounding the core and comprising a wax and two or more grades of low-substituted hydroxypropyl cellulose (L-HPC)

Drug release: The core tablet releases drug in a sustained manner over a period of 2-12 hours after initiation of drug active ingredient release.

2020

[76]

5

US20200188309A1

Delayed release tablet

It discloses a delayed release tablet containing deferiprone and enteric polymer which is chosen from hydroxypropyl methylcellulose (HPMC) acetate succinate, HPMC phthalate, polyvinyl acetate phthalate, methacrylic acid copolymers, etc.
 Pharmacokinetic parameter: single dose of the tablet provides a mean AUCI/Cmax ratio between 3.5 hours and 6.0 hours in fasted state and/or fed state

2020

[77]