WO2015110968A1 - Pharmaceutical grade ferric citrate and method for its production - Google Patents

Pharmaceutical grade ferric citrate and method for its production Download PDF

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Publication number
WO2015110968A1
WO2015110968A1 PCT/IB2015/050465 IB2015050465W WO2015110968A1 WO 2015110968 A1 WO2015110968 A1 WO 2015110968A1 IB 2015050465 W IB2015050465 W IB 2015050465W WO 2015110968 A1 WO2015110968 A1 WO 2015110968A1
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WO
WIPO (PCT)
Prior art keywords
ferric
ferric citrate
citrate
pharmaceutical grade
preparing
Prior art date
Application number
PCT/IB2015/050465
Other languages
French (fr)
Inventor
Sunilkumar Vinubhai Gohel
Yogesh Subhash AHER
Pankaj Ramchandra CHAUDHARI
Rajinder Singh Siyan
Nandu Baban Bhise
Girij Pal Singh
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Lupin Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Publication date
Application filed by Lupin Limited filed Critical Lupin Limited
Publication of WO2015110968A1 publication Critical patent/WO2015110968A1/en

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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
    • C07C51/41—Preparation of salts of carboxylic acids
    • C07C51/412—Preparation of salts of carboxylic acids by conversion of the acids, their salts, esters or anhydrides with the same carboxylic acid part
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K31/00—Medicinal preparations containing organic active ingredients
    • A61K31/28—Compounds containing heavy metals
    • A61K31/295—Iron group metal compounds

Definitions

  • the present invention relates to a coordination complex of ferric citrate and ferric containing compounds, a method for production and medical use thereof.
  • Coordination complexes of ferric citrate and ferric containing compounds are inorganic, iron- based compounds that have the capacity to bind to phosphates and form non-absorbable complexes with phosphates. Such ferric compounds are useful for the treatment of hyperphosphatemia and metabolic acidosis.
  • ferric compounds such as ferric citrate, ferric ammonium citrate and ferric chloride as phosphate binders have been reported in various publications.
  • Objective of the present invention is to provide a pharmaceutical grade ferric citrate.
  • a second objective of the present invention is to provide pharmaceutical grade ferric citrate having BET active surface area in the range of 1 - 15 m /gm.
  • a third objective of the present invention is to provide a pharmaceutical composition
  • a pharmaceutical composition comprising a therapeutically effective amount of pharmaceutical grade ferric citrate and a pharmaceutically acceptable carrier, excipient or diluent.
  • Another objective of the present invention is to provide a pharmaceutical grade ferric citrate for the treatment and/or prevention of hyperphosphatemia and metabolic acidosis.
  • Another objective of the present invention is to provide an improved process for preparation of the said pharmaceutical grade ferric citrate.
  • a process for the preparation of pharmaceutical grade ferric citrate of the present invention comprises of combining ferric and citrate ions in water and precipitating the ferric citrate from the aqueous solution by using an organic solvent.
  • the organic solvent comprises alcohols such as methanol, ethanol, isopropanol, etc.; ethers such as tetrahydrofuran etc.; and ketones such as acetone etc.; or a mixture thereof.
  • the present invention does not involve formation of ferric hydroxide, thereby avoids the cumbersome separation of the same. Said process also avoids formation of impurities due to exposure of ferric hydroxide to air during unit operations.
  • the source of ferric ion is ferric chloride, ferric nitrate or ferric sulfate; preferably hydrated ferric chloride salt and source of citrate ion is salt of citric acid; more preferably trisodiumcitrate dihydrate.
  • One of the methods for manufacturing pharmaceutical grade ferric citrate in accordance with the present invention comprises of mixing the source of citrate ion and ferric chloride hexahydrate in water to obtain a solution and precipitating the desired pharmaceutical grade ferric citrate by adding alcohol to the solution.
  • the pharmaceutical grade ferric citrate of the present invention is synthesized by adding citric acid monohydrate to aqueous solution of sodium hydroxide followed by addition of ferric chloride hexahydrate and precipitating the ferric citrate by gradual addition of methanol.
  • the pharmaceutical grade ferric citrate of the present invention is synthesized by mixing of aqueous solution of trisodiumcitrate dihydrate with ferric chloride hexahydrate and precipitating the ferric citrate by gradual addition of methanol.
  • the reaction is carried out at a temperature between about 50 and about 100 °C, preferably between about 55 and about 90 °C.
  • the obtained precipitate of ferric citrate is isolated, for example by decantation, filtration, centrifugation, preferably by filtration, and then washed with alcohol.
  • the alcohol comprises methanol, ethanol, isopropanol, etc.; preferably methanol.
  • the product is dried under vacuum at about 50 to 100 °C, preferably at about 75 to 95 °C for 5-24 hours, preferably for 5-18 hours, or more preferably for 10-12 hours.
  • the pharmaceutical grade ferric citrate is optionally purified by using alcohol to improve colour and texture.
  • the pharmaceutical grade ferric citrate according to the invention is useful in the treatment and/or prevention of hyperphosphatemia and metabolic acidosis in humans.
  • This invention further relates to a composition for treating hyperphosphatemia and metabolic acidosis in the humans, comprising an effective amount of the pharmaceutical grade ferric citrate.
  • a pharmaceutical composition, for the treatment of hyperphosphatemia and metabolic acidosis, comprising the ferric citrate of the present invention can be administered by orally.
  • the present invention also provides use of pharmaceutical grade ferric citrate of the present invention in the manufacture of a medicament for treatment of hyperphosphatemia and metabolic acidosis.
  • a pharmaceutical formulation can be adequately provided in unit dosage form and it can be prepared by any method well-known in the field of pharmaceutical technology. Such method comprises a step of mixing pharmaceutical grade ferric citrate of the present invention with at least one auxiliary ingredient (e.g., a carrier).
  • auxiliary ingredient e.g., a carrier
  • forms of pharmaceutical formulations include, but are not limited to, oral formulations, such as tablets, pills, capsules, granules, powders, and suspending agents.
  • Example- 1 Preparation of Ferric Citrate

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  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Organic Chemistry (AREA)
  • Animal Behavior & Ethology (AREA)
  • Epidemiology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Pharmacology & Pharmacy (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Engineering & Computer Science (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Medicinal Chemistry (AREA)
  • Medicinal Preparation (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)

Abstract

Ferric citrate is provided having a BET active surface area in the range of 1-15 m2 /gm. A method for preparing pharmaceutical grade ferric citrate is also provided.

Description

PHARMACEUTICAL GRADE FERRIC CITRATE AND METHOD FOR ITS
PRODUCTION
Field of the invention
The present invention relates to a coordination complex of ferric citrate and ferric containing compounds, a method for production and medical use thereof.
Background and the prior art
Coordination complexes of ferric citrate and ferric containing compounds are inorganic, iron- based compounds that have the capacity to bind to phosphates and form non-absorbable complexes with phosphates. Such ferric compounds are useful for the treatment of hyperphosphatemia and metabolic acidosis.
Studies on the efficacy and tolerability of ferric compounds such as ferric citrate, ferric ammonium citrate and ferric chloride as phosphate binders have been reported in various publications.
Prior studies (US5753706, J Am Soc Neprol, Vol.10, Pagesl274-1280, 1999) indicate that Ferric compounds are known to bind to dietary phosphate and dramatically alter phosphate metabolism.
Method of preparation of pharmaceutical grade ferric citrate having BET active surface area of at least 16 m /gm is mentioned in US7767851 & US8093423 for treating disorders related to hypophosphatemia.
So there exists a scope to develop an improved process that yields pharmaceutical grade ferric citrate having BET active surface area in the range of 1-15 m7 gm. Ob ject of the invention
Objective of the present invention is to provide a pharmaceutical grade ferric citrate.
A second objective of the present invention is to provide pharmaceutical grade ferric citrate having BET active surface area in the range of 1 - 15 m /gm.
A third objective of the present invention is to provide a pharmaceutical composition comprising a therapeutically effective amount of pharmaceutical grade ferric citrate and a pharmaceutically acceptable carrier, excipient or diluent.
Another objective of the present invention is to provide a pharmaceutical grade ferric citrate for the treatment and/or prevention of hyperphosphatemia and metabolic acidosis.
Another objective of the present invention is to provide an improved process for preparation of the said pharmaceutical grade ferric citrate.
Description of the invention
A process for the preparation of pharmaceutical grade ferric citrate of the present invention comprises of combining ferric and citrate ions in water and precipitating the ferric citrate from the aqueous solution by using an organic solvent. The organic solvent comprises alcohols such as methanol, ethanol, isopropanol, etc.; ethers such as tetrahydrofuran etc.; and ketones such as acetone etc.; or a mixture thereof.
The present invention does not involve formation of ferric hydroxide, thereby avoids the cumbersome separation of the same. Said process also avoids formation of impurities due to exposure of ferric hydroxide to air during unit operations. According to the present invention, the source of ferric ion is ferric chloride, ferric nitrate or ferric sulfate; preferably hydrated ferric chloride salt and source of citrate ion is salt of citric acid; more preferably trisodiumcitrate dihydrate. One of the methods for manufacturing pharmaceutical grade ferric citrate in accordance with the present invention comprises of mixing the source of citrate ion and ferric chloride hexahydrate in water to obtain a solution and precipitating the desired pharmaceutical grade ferric citrate by adding alcohol to the solution. According to the present invention, the pharmaceutical grade ferric citrate of the present invention is synthesized by adding citric acid monohydrate to aqueous solution of sodium hydroxide followed by addition of ferric chloride hexahydrate and precipitating the ferric citrate by gradual addition of methanol. Alternatively, the pharmaceutical grade ferric citrate of the present invention is synthesized by mixing of aqueous solution of trisodiumcitrate dihydrate with ferric chloride hexahydrate and precipitating the ferric citrate by gradual addition of methanol.
According to the present invention, the reaction is carried out at a temperature between about 50 and about 100 °C, preferably between about 55 and about 90 °C.
According to the present invention, the obtained precipitate of ferric citrate is isolated, for example by decantation, filtration, centrifugation, preferably by filtration, and then washed with alcohol. The alcohol comprises methanol, ethanol, isopropanol, etc.; preferably methanol.
According to the present invention, the product is dried under vacuum at about 50 to 100 °C, preferably at about 75 to 95 °C for 5-24 hours, preferably for 5-18 hours, or more preferably for 10-12 hours. The pharmaceutical grade ferric citrate is optionally purified by using alcohol to improve colour and texture.
The pharmaceutical grade ferric citrate according to the invention is useful in the treatment and/or prevention of hyperphosphatemia and metabolic acidosis in humans.
This invention further relates to a composition for treating hyperphosphatemia and metabolic acidosis in the humans, comprising an effective amount of the pharmaceutical grade ferric citrate.
A pharmaceutical composition, for the treatment of hyperphosphatemia and metabolic acidosis, comprising the ferric citrate of the present invention can be administered by orally.
The present invention also provides use of pharmaceutical grade ferric citrate of the present invention in the manufacture of a medicament for treatment of hyperphosphatemia and metabolic acidosis.
A pharmaceutical formulation can be adequately provided in unit dosage form and it can be prepared by any method well-known in the field of pharmaceutical technology. Such method comprises a step of mixing pharmaceutical grade ferric citrate of the present invention with at least one auxiliary ingredient (e.g., a carrier).
Examples of forms of pharmaceutical formulations (dosage forms) include, but are not limited to, oral formulations, such as tablets, pills, capsules, granules, powders, and suspending agents.
Present invention is further illustrated with the following non-limiting examples. Example- 1: Preparation of Ferric Citrate
To a 1.0L four-neck round bottom flask, 150 gm trisodiumcitrate dihydrate and 172 ml purified water were added. The reaction mass was stirred for 30 minutes to get clear solution. 138 gm ferric chloride hexahydrate was added to the solution and further stirred for 1 hour at 80-90°C. The reaction mass was cooled to 30°C and passed through filter paper. 1230 ml methanol was slowly added into the filtrate and stirred for 1 hour. Precipitated product was filtered and washed with 120 ml methanol. The product was dried under reduced pressure in vacuum oven at 90°C.
Yield: 78% molar yield
Description: light yellow to brown colored powder
BET Active Specific Surface Area: 1.7 m2/gm
Example-2: Preparation of Ferric Citrate
To a 2.0 L four-neck round bottom flask, 200 ml purified water and 44.4 gm sodium hydroxide were added and stirred to make a solution. To the reaction mass, 77.7 gm citric acid monohydrate was added and stirred for 30 minutes. Thereafter, 100 gm ferric chloride hexahydrate was added to the reaction mass and further stirred fori hour at 50-55°C. The reaction mass was cooled to 25 °C and subsequently, 1200 ml of methanol was slowly added to the reaction mass and stirred for 1 hour. Precipitated product was filtered and washed with 100 ml of methanol. The wet product was dried under reduced pressure.
Yield: 85% molar yield
Description: dark brown colored to red colored powder
BET Active Specific Surface Area: 11.7 m2/gm Example-3: Purification of Ferric Citrate:
To a 2.0 L four-neck round bottom flask, 150 ml of purified water and 100 gm ferric citrate was added under stirring at room temperature and the reaction mixture was stirred for 1 hour to get clear solution. Thereafter, 1000 ml of methanol was added to the reaction mass and further stirred for 1 hour at room temperature. Precipitated product was filtered and with 100 ml of methanol. The wet product was dried under reduced pressure.
Yield: 80% molar yield
Description: light yellow to brown colored powder
BET Active Specific Surface Area: 1.0 m2/gm

Claims

1. Ferric citrate having a BET active surface area in the range of 1-15 m7 gm.
2. A method for preparing pharmaceutical grade ferric citrate, comprising:
a. mixing source of citrate ion with source of ferric ion in aqueous solution;
b. adding alcohol to the above solution; and
c. filtering the mixture to obtain pharmaceutical grade ferric citrate.
3. A method for preparing the ferric citrate of claim 2, wherein the source citric ion is selected from citric acid or trisodium citrate.
4. A method for preparing the ferric citrate of claim 2, wherein the source ferric ion is selected from ferric chloride, ferric nitrate or ferric sulphate.
5. A method for preparing the ferric citrate of claim 4, wherein the source ferric ion is ferric chloride hexahydrate.
6. A method for preparing the ferric citrate of claim 2, wherein the alcohol is selected from methanol, ethanol or isopropyl alcohol.
7. A pharmaceutical composition comprising ferric citrate according to claim 1, having a BET active surface area in the range of 1-15 m /gm and a suitable carrier.
8. The pharmaceutical composition of claim 7, wherein said composition is in an orally administrable form.
9. The pharmaceutical composition of claim 8, wherein the orally administrable form is selected from a tablet, a pill, a capsule, a granule, a powder or a suspension.
10. The pharmaceutical composition of claim 9, wherein the orally administrable form is a tablet.
11. A method of treating hyperphosphatemia comprising administering ferric citrate according to claim 1, having a BET active surface area in the range of 1-15 m /gm.
12. A method of treating metabolic acidosis comprising administering ferric citrateaccording to claim 1, having a BET active surface area in the range of 1-15 m 2 //gm.
PCT/IB2015/050465 2014-01-23 2015-01-21 Pharmaceutical grade ferric citrate and method for its production WO2015110968A1 (en)

Applications Claiming Priority (2)

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IN241/MUM/2014 2014-01-23
IN241MU2014 2014-01-23

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016162888A1 (en) * 2015-04-09 2016-10-13 Actavis Group Ptc Ehf. Process for preparing pharmaceutical grade ferric citrate
WO2017021921A1 (en) * 2015-08-05 2017-02-09 Lupin Limited Process for the preparation of pharmaceutical grade ferric citrate
US10172882B2 (en) 2014-06-22 2019-01-08 Dexcel Pharma Technologies Ltd. Pharmaceutical compositions comprising ferric citrate and methods for the production thereof
WO2019012553A1 (en) * 2017-07-12 2019-01-17 Ra Chem Pharma Process for preparation of compositions of ferric organic compounds
WO2019012552A1 (en) * 2017-07-12 2019-01-17 Ra Chem Pharma Compositions of ferric organic compounds
WO2020100912A1 (en) * 2018-11-14 2020-05-22 株式会社トクヤマ Method for producing ferric citrate hydrate
WO2020100911A1 (en) * 2018-11-14 2020-05-22 株式会社トクヤマ Method for producing ferric citrate hydrate
WO2021089766A1 (en) 2019-11-08 2021-05-14 Química Sintética, S.A. Process for the preparation of ferric organic compounds
US11560339B2 (en) 2019-05-30 2023-01-24 Koch Agronomie Services, LLC Micronutrient foliar solutions

Citations (6)

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Publication number Priority date Publication date Assignee Title
US3091626A (en) * 1960-06-20 1963-05-28 Scherer Corp R P Method of making ferrous citrate
US5753706A (en) 1996-12-16 1998-05-19 Hsu; Chen Hsing Methods for treating renal failure
WO2004074444A2 (en) * 2003-02-19 2004-09-02 Globoasia Llc Ferric organic compounds, uses thereof and methods of making same
US20050080283A1 (en) * 2003-10-08 2005-04-14 Yih-Ming Hsiao Pharmaceutical-grade ferric citrate
US8093423B2 (en) 2003-02-19 2012-01-10 Globoasia, Llc Pharmaceutical-grade ferric organic compounds, uses thereof and method of making same
WO2013192565A2 (en) * 2012-06-21 2013-12-27 Keryx Biopharmaceuticals, Inc. Use of ferric citrate in the treatment of chronic kidney disease patients

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3091626A (en) * 1960-06-20 1963-05-28 Scherer Corp R P Method of making ferrous citrate
US5753706A (en) 1996-12-16 1998-05-19 Hsu; Chen Hsing Methods for treating renal failure
WO2004074444A2 (en) * 2003-02-19 2004-09-02 Globoasia Llc Ferric organic compounds, uses thereof and methods of making same
US7767851B2 (en) 2003-02-19 2010-08-03 Panion & Bf Biotech, Inc. Ferric organic compounds, uses thereof and methods of making same
US8093423B2 (en) 2003-02-19 2012-01-10 Globoasia, Llc Pharmaceutical-grade ferric organic compounds, uses thereof and method of making same
US20050080283A1 (en) * 2003-10-08 2005-04-14 Yih-Ming Hsiao Pharmaceutical-grade ferric citrate
WO2013192565A2 (en) * 2012-06-21 2013-12-27 Keryx Biopharmaceuticals, Inc. Use of ferric citrate in the treatment of chronic kidney disease patients

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
J AM SOC NEPROL, vol. 10, 1999, pages 1274 - 1280

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10172882B2 (en) 2014-06-22 2019-01-08 Dexcel Pharma Technologies Ltd. Pharmaceutical compositions comprising ferric citrate and methods for the production thereof
WO2016162888A1 (en) * 2015-04-09 2016-10-13 Actavis Group Ptc Ehf. Process for preparing pharmaceutical grade ferric citrate
WO2017021921A1 (en) * 2015-08-05 2017-02-09 Lupin Limited Process for the preparation of pharmaceutical grade ferric citrate
US20180222836A1 (en) * 2015-08-05 2018-08-09 Lupin Limited Process for the Preparation of Pharmaceutical Grade Ferric Citrate
WO2019012553A1 (en) * 2017-07-12 2019-01-17 Ra Chem Pharma Process for preparation of compositions of ferric organic compounds
WO2019012552A1 (en) * 2017-07-12 2019-01-17 Ra Chem Pharma Compositions of ferric organic compounds
CN112955138B (en) * 2018-11-14 2023-08-22 株式会社德山 Method for producing ferric citrate hydrate
WO2020100911A1 (en) * 2018-11-14 2020-05-22 株式会社トクヤマ Method for producing ferric citrate hydrate
CN112955138A (en) * 2018-11-14 2021-06-11 株式会社德山 Method for producing ferric citrate hydrate
CN112969456A (en) * 2018-11-14 2021-06-15 株式会社德山 Method for producing ferric citrate hydrate
WO2020100912A1 (en) * 2018-11-14 2020-05-22 株式会社トクヤマ Method for producing ferric citrate hydrate
JP7335268B2 (en) 2018-11-14 2023-08-29 株式会社トクヤマ Method for producing ferric citrate hydrate
JP7335269B2 (en) 2018-11-14 2023-08-29 株式会社トクヤマ Method for producing ferric citrate hydrate
CN112969456B (en) * 2018-11-14 2023-10-17 株式会社德山 Method for producing ferric citrate hydrate
US11560339B2 (en) 2019-05-30 2023-01-24 Koch Agronomie Services, LLC Micronutrient foliar solutions
WO2021089766A1 (en) 2019-11-08 2021-05-14 Química Sintética, S.A. Process for the preparation of ferric organic compounds
US11926586B2 (en) 2019-11-08 2024-03-12 Química Sintética, S.A. Process for the preparation of ferric organic compounds

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