WO2009145716A1

WO2009145716A1 - New pharmaceutical formulation useful in gerd therapy

Info

Publication number: WO2009145716A1
Application number: PCT/SE2009/050603
Authority: WO
Inventors: Anders Lehmann; Hans Rydholm; Michael Wrangstadh
Original assignee: Astrazeneca Ab
Priority date: 2008-05-28
Filing date: 2009-05-27
Publication date: 2009-12-03

Abstract

The present invention is directed to a pharmaceutical formulation comprising 3-Amino-2-f luoropropyl phosphinic acid or an enantiomer thereof, or a pharmaceutically and pharmacologically acceptable salt thereof, and its use for reducing paraesthesia in the treatment of GERD by administration of said compound.

Description

NEW PHARMACEUTICAL FORMULATION USEFUL IN GERD THERAPY

Field of the Invention

The present invention is directed to a pharmaceutical formulation comprising 3-Amino-2- fluoropropyl phosphinic acid, or an enantiomer thereof, as well as the use of said formulation for the treatment of gastro-esophageal reflux disease (GERD).

Background of the invention

Gastroesophageal reflux disease (GERD) is the most prevalent upper gastrointestinal tract disease. Current therapy has been aimed at reducing gastric acid secretion, or reducing esophageal acid exposure by enhancing esophageal clearance, lower esophageal sphincter tone and gastric emptying. The major mechanism behind reflux is the relaxation of the lower esophageal sphincter allowing gastric contents into the esophagus, (note: A hypotonic sphincter or a low sphincter pressure is not the primary cause of reflux). Recent research has shown that most reflux episodes occur during transient lower esophageal sphincter relaxations (TLESR) i.e. relaxations not triggered by swallows (e.g. Holloway & Dent, Gastroenterol. Clin. N. Amer. 19, 517-535). It has also been shown that gastric acid secretion usually is normal in patients with GERD.

GABA (4-aminobutanoic acid) is an endogenous neurotransmitter in the central and peripheral nervous systems. Receptors for GABA have traditionally been divided into GABA_A and GABA_B receptor subtypes. GABA_B receptors (for a review see Kerr, D. LB. and Ong, J (1995), Pharm. Ther., vol. 67, pp 187-246) belong to the superfamily of G- protein coupled receptors. GABA_B receptor agonists are described as being of use in the treatment of CNS disorders, such as muscle relaxation in spinal spasticity, gastroesophageal reflux inhibitors (WO 98/11885), cardiovascular disorders, asthma, gut motility disorders such as irritable bowel syndrome and as prokinetic and anti-tussive agents. GABA_B receptor agonists have also been disclosed as useful in the treatment of emesis (WO 96/11680). The GABA_B receptor agonist baclofen (4-amino-3-(4-chlorophenyl)-butanoic acid (CH 449,046), is the most studied of the GABA analogs. Baclofen is known as a muscle relaxant and antispasmic agent (see e.g. Martindale, The Extra Pharmacopoeia, 1993). GABA_B receptor agonists or partial agonists are also disclosed in EP 356128; EP 181833; EP 399949; EP 463969 and FR 2,722,192.

US 5,091,184 and US 5,651,985 disclose pharmaceutical compositions of baclofen.

WO 98/11885 discloses inter alia the use of a GABA_B receptor agonist for the inhibition of TLESR and treatment of GERD. WO 01/42252 discloses certain GABA_B receptor agonists useful for inter alia the inhibition of TLESR and treatment of GERD.

WO 2005/097079 discloses a pharmaceutical dosage form of a GABA_B receptor agonist.

WO 2006/128070 discloses pharmaceutical dosage forms of baclofen.

EP 220 143 discloses a formulation of metoprolol. EP 277 127 discloses a drug formulation with a compact insoluble core material. WO 2005/013939 discloses a method for the preparation of beads coated with a water-soluble drug.

GABA_B receptor agonists are inter alia known for use in the treatment of spasms, cramping, tightness of muscles, or spasticity associated with ailments such as multiple sclerosis, spinal cord diseases or certain spinal injuries (see e.g. Martindale, The Extra Pharmacopoeia, 1993). A side effect that has been reported for certain GABA_B receptor agonists (see e.g. Martindale, The Extra Pharmacopoeia, 1993) is paresthesiae (also sometimes referred to as tingling), a sensation of repetitive moving pin pricks, caused by cold or by striking a nerve, or as a result of various diseases of the central or peripheral nervous system.

WO 97/25028 discloses controlled release beads comprising furosemide, wherein the release profile of furosemide is not more than 30 % after 60 minutes, not more than 44 % after 120 minutes and more than 80 % after 360 minutes. Outline of the invention

An aspect of the invention is to provide a pharmaceutical formulation comprising the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, or a pharmaceutically and pharmacologically acceptable salt thereof.

Administration by slowly increasing the plasma concentration during 30 minutes from initiation of administration of 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, may reduce paraesthesia. Paraesthesia is a side effect that has been reported in clinical studies for (2R)-3-Amino-2-fluoropropyl phosphinic acid.

Yet an aspect of the invention, is a pharmaceutical formulation as described above, providing a drug release profile of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, such that substantially all administered compound is released in the gastrointestinal tract within 5 hours from the time of administration.

An aspect of the present invention is a pharmaceutical formulation comprising the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, or a pharmaceutically and pharmacologically acceptable salt thereof, said formulation having a release profile in vivo in human, such that

(i) up to 20% of the maximum mean blood plasma concentration (C_max) but not more than

0.2 μM, of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is obtained within 15 minutes after administration;

(ii) up to 60 % of the maximum mean blood plasma concentration (C_max) but not more than 0.60 μM, of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is obtained within 30 minutes after administration; and (iii) the maximum mean blood plasma concentration (C_max) of the compound 3-Amino-2- fluoropropyl phosphinic acid or an enantiomer thereof, is at least 1.3 μmol/1 and is obtained during 1.5-4.0 hours from the time of administration.

(i) up to 20% of the maximum mean blood plasma concentration (C_max) but not more than 0.2 μM, of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is obtained within 15 minutes after administration;

(ii) up to 60 % of the maximum mean blood plasma concentration (C_max) but not more than 0.60 μM, of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is obtained within 30 minutes after administration; and

(iii) the maximum mean blood plasma concentration (C_max) of the compound 3- Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is at least 1.3 μmol/1 and is obtained during 1.5-3.5 hours from the time of administration.

An aspect of the present invention is a pharmaceutical formulation comprising the compound 3 -Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, or a pharmaceutically and pharmacologically acceptable salt thereof, said formulation having a release profile in vivo in human, such that (i) up to 20% of the maximum mean blood plasma concentration (C_max) but not more than 0.2 μM, of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is obtained within 15 minutes after administration;

(iii) the maximum mean blood plasma concentration (C_max) of the compound 3-

Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is at least 1.3 μmol/1 and is obtained during 1.5-3.0 hours from the time of administration.

An aspect of the present invention is a pharmaceutical formulation comprising the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, said formulation having a release profile in vivo in human, such that

(i) up to 15 % of the maximum mean blood plasma concentration (C_max) but not more than 0.2 μM, of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is obtained within 15 minutes after administration;

(ii) up to 40 % of the maximum mean blood plasma concentration (C_max) but not more than 0.5 μM, of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is obtained within 30 minutes after administration; and

(iii) the maximum mean blood plasma concentration (C_max) of the compound 3-

Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is at least 1.3 μmol/1 and is obtained during 1.5-4.0 hours from the time of administration. An aspect of the present invention is a pharmaceutical formulation comprising the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, said formulation having a release profile in vivo in human, such that

(iii) the maximum mean blood plasma concentration (C_max) of the compound 3-

Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is at least 1.3 μmol/1 and is obtained during 1.5-3.5 hours from the time of administration.

(ii) up to 40 % of the maximum mean blood plasma concentration (C_max) but not more than 0.5 μM, of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is obtained within 30 minutes after administration; and (iii) the maximum mean blood plasma concentration (C_max) of the compound 3- Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is at least 1.3 μmol/1 and is obtained during 1.5-3.0 hours from the time of administration.

A further aspect of the present invention is a pharmaceutical formulation comprising the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, said formulation having a release profile in vitro, wherein

(i) up to 45 % of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is released within 15 minutes after immersion in an USPII bath; and

(ii) up to 75 % of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is released within 30 minutes after immersion in an USPII bath.

Still a further aspect of the present invention is a pharmaceutical formulation comprising a compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, said formulation having a release profile in vitro, wherein

(i) up to 35 % of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is released within 15 minutes after immersion in an USPII bath; and

(ii) up to 65 % of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is released within 30 minutes after immersion in an USPII bath. An aspect of the present invention is a pharmaceutical formulation comprising the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, said formulation having a release profile in vitro, wherein

(i) up to 45 % of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is released within 15 minutes after immersion in an USPII bath;

(ii) up to 75 % of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is released within 30 minutes after immersion in an USPII bath;

(iii) 30-100 % of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is released within 60 minutes after immersion in an USPII bath; and

(iv) 60-100 % of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is released within 120 minutes after immersion in an USPII bath.

One embodiment of the present invention is a method for the treatment or prevention of gastro-esophageal reflux disease(GERD), wherein a pharmaceutical formulation as described herein is administered to a subject in need of such treatment or prevention.

Yet an aspect of the present invention is the use of a pharmaceutical formulation as herein described, for the manufacture of a medicament for the treatment of GERD.

Still an aspect of the present invention is a pharmaceutical formulation as herein described, for use in the treatment of GERD. One embodiment of the invention is a method for the treatment or prevention of GERD, wherein the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is administered by fractional administration to a subject in need of such treatment or prevention.

One aspect of present invention is a pharmaceutical formulation comprising:

(i) a core having a size of from 100-700 μm;

(ii) said core being coated with from 0.4 to 0.99 mg of the compound 3-Amino-2- fluoropropyl phosphinic acid or an enantiomer thereof, or a pharmaceutically and pharmacologically acceptable salt thereof, calculated based on the compound in non-salt form per mg pellet;

(iii) a polymer film coating which is a polymer mixture, in an amount of from 10-50

% by weight of the final coated product.

The wording "final coated product" is herein defined as a pellet coated with a polymer film coating as herein described and claimed.

A daily dose of (2i?)-(3-Amino-2-fluoropropyl)phosphinic acid or a pharmaceutically acceptable salt thereof useful in accordance with the invention, may be up to 2200 mg per day, such as up to 480 mg per day. The compound may for example be administered once or twice daily. In one embodiment of the invention the compound may be administered in a dose of up to 240 mg bid (i.e. twice daily amounting to up to 480 mg per day).

In one embodiment of the invention, (2i?)-(3-Amino-2-fluoropropyl)phosphinic acid or a pharmaceutically acceptable salt thereof, may be administered in a dose of from 60 to 240 mg bid. In yet an embodiment, the daily dose of (2i?)-(3-Amino-2-fluoropropyl)phosphinic acid or a pharmaceutically acceptable salt thereof, may be administered in a dosage such as 120 mg bid and 240 mg bid. The wording bid means that a compound is administered twice daily, and the daily dose of a compound may be such as 120 mg, 240 mg and 480 mg.

In one embodiment of the invention, a pharmaceutical formulation as herein described is administered once daily. In a further embodiment, a pharmaceutical formulation as herein described is administered twice daily.

A further aspect of the invention is a pharmaceutical formulation as herein described, for use in symptom control in "a partial responder to PPI therapy". The wording "partial responder to PPI treatment" is herein defined as a patient or subject with persistent GERD symptoms despite PPI treatment.

In one embodiment of the invention a pharmaceutical formulation according to the invention may be useful for the treatment of GERD-related or non-GERD related asthma, belching, coughing, pain, ***e addiction, hiccups, IBS, dyspepsia, emesis and nociception.

In yet a further embodiment of the invention the pharmaceutical formulation may be useful for the treatment of regurgitation, treatment or prevention of lung disease, management of failure to thrive, treatment or prevention of esophagitis, treatment of laryngitis such as chronic laryngitis, Barrett's esophageus, or prevention of reflux. Yet an aspect of the present invention is the use of a pharmaceutical formulation as described and claimed herein, for the manufacture of a medicament for the treatment of non-erosive reflux disease (NERD).

Examples of PPI therapy may without limitation be proton pump inhibitors such as pyridinylmethylsulfinyl benzimidazoles such as omeprazole, esomeprazole, lansoprazole, pantoprazole, rabeprazole or related substances such as leminoprazole. A further aspect of the present invention, is a pharmaceutical formulation as herein described, for use in a patient already being subjected to treatment with an acid inhibiting agent. The wording "acid inhibiting agent" used in accordance with the present invention comprises inter alia H2 blocking agents, such as cimetidine, ranitidine, famotidine, and nizatidine.

Yet an aspect of the present invention, is a pharmaceutical formulation as herein described, for use in a patient already being subjected to treatment with a potassium channel competitive acid blocker (PCAB).

The compound 3-Amino-2-fluoropropyl phosphinic acid is herein defined as the racemate as well as the R- and the S-enantiomer thereof. Thus, the wording "compound" as used throughout the specification and claims, includes 3-Amino-2-fluoropropyl phosphinic acid in the racemate form, (2R)-3-Amino-2-fluoropropyl phosphinic acid and (2S)-3-Amino-2- fluoropropyl phosphinic acid. Also within the scope of the wording "compound" is a pharmaceutically and pharmacologically acceptable salt of any one of said compounds.

Paresthesiae or tingling as used herein is defined as an unspecific symptom of central or peripheral origin and includes a sensation of repetitive moving pin pricks, caused by cold or by striking a nerve, or as a result of various diseases of the central or peripheral nervous system.

The phrase "USPII bath" or USP Apparatus II is the device commonly used to conduct dissolution testing in the pharmaceutical industry, see the US Pharmacopoeia chapter <711>, Dissolution.

The term "core" as used herein, is defined as a solid particle of a defined size, expressed as its diameter (volume based diameter as measured by Laser diffraction), used for further processing as herein described. A "core" material within the scope of the invention may be the compound 3-Amino-2-fluoropropyl phosphinic acid or a pharmaceutically and pharmacologically acceptable salt thereof; the compound (2R)-3-Amino-2-fluoropropyl phosphinic acid or a pharmaceutically and pharmacologically acceptable salt thereof; the compound (2S)-3-Amino-2-fluoropropyl phosphinic acid or a pharmaceutically and pharmacologically acceptable salt thereof; microcrystalline cellulose such as Celphere CP- 203 (200-300 μm), Celphere CP-305 (300-500 μm) or Celphere 507 (500-700 μm); silicon dioxide (sand); or sucrose.

The term "pellet" as used herein is defined as a core coated with any one of the compound 3-Amino-2-fluoropropyl phosphinic acid or a pharmaceutically and pharmacologically acceptable salt thereof; the compound (2R)-3-Amino-2-fluoropropyl phosphinic acid or a pharmaceutically and pharmacologically acceptable salt thereof; or the compound (2S)-3- Amino-2-fluoropropyl phosphinic acid or a pharmaceutically and pharmacologically acceptable salt thereof.

The wording "pellet" as used herein also encompasses a solid particle as described above, compressed into a unit and having a diameter of approximately 1, 2, 3 or 4 mm.

In one aspect of the present invention, the wording "C_max " as used herein, is defined as the mean peak blood plasma concentration of the compound (2R)-3-Amino-2-fluoropropyl- phosphinic acid.

In one aspect of the present invention, the wording "C_max " as used herein, is defined as the mean peak blood plasma concentration of the compound (2S)-3-Amino-2-fluoropropyl- phosphinic acid.

In one aspect of the present invention, the wording "C_max " as used herein, is defined as the mean peak blood plasma concentration of the compound 3 -Amino-2-fluoropropyl phosphinic- acid as the racemate. Methods of preparation

Compounds

The compounds 3-Amino-2-fluoropropyl phosphinic acid, (2R)-3-Amino-2-fluoropropyl phosphinic acid and (2S)-3-Amino-2-fluoropropyl phosphinic acid, may be prepared as described in WO 01/42252.

(2R)-(3-Amino-2-fluoropropyl)phosphinic acid form A may be prepared by dissolution of (2R)-3-[(tert-butoxycarbonyl)amino]-2-fluoro-propyl phosphinic acid ammonium salt in a polar solvent, for example methanol, isopropanol or water and treatment of the solution with an acid at an elevated temperature, for example at a temperature of from 50-60⁰C. The reaction mixture is cooled to 3O⁰C and pH is adjusted to 5-6 by addition of a base. Inorganic salts may form which are precipitated and removed.

(2R)-(3-Amino-2-fluoropropyl)phosphinic acid form B is prepared by dissolving (2R)-(3- Amino-2-fluoropropyl)phosphinic acid form A in a polar solvent, for example methanol or water or a mixture thereof. The mixture is heated to an elevated temperature, for example 40-50⁰C. An anti-solvent is added over a period of hours, for example 10 hours. The mixture is stirred and held at an elevated temperature, for example at a temperature of 4O⁰C over a period of hours, for example at a time of 33 hours. The slurry is cooled and formed crystals are isolated and dried.

Crystallisation of (2R)-(3-Amino-2-fluoropropyl)phosphinic acid is initiated by adding an anti-solvent or a mixture of anti-solvents, for example acetonitrile, acetone, ethanol, isopropanol or ethylacetate at an elevated temperature, for example 40-70⁰C. The slurry is cooled and formed crystals are isolated and dried.

(2R)-(3-Amino-2-fluoropropyl)phosphinic acid is a zwitterion and zwitterions may be crystallised at the isoelectric point, in this case approximately at pH 5.3. As the reaction is performed during acidic conditions, the protonated species of (2R)-(3- Amino-2-fluoropropyl)phosphinic acid is formed. After completed reaction the pH is adjusted to 5-6 by addition of a base in order to isolate (2R)-(3-Amino-2- fluoropropyl)phosphinic acid crude as the zwitterion. The solution of (2R)-(3-Amino-2- fluoropropyl)phosphinic acid works as a buffer solution and the amount of base added to reach the set pH-interval (5-6) can be varied between 1.8-2.8 equivalents.

A solute is crystallized from a primary solvent by the addition of a second solvent, "anti- solvent", in which the solute is relatively insoluble. The anti-solvent is miscible with the primary solvent and brings about a solubility decrease of the solute in the resulting binary solvent mixture (see e.g. Allan S. Myerson, Handbook of Industrial Crystallization, second edition).

Bases used for pH adjustment is for example NH3 in methanol or ammonium acetate dissolved in methanol.

The formed crystals of (2R)-(3-Amino-2-fluoro-propyl)-phosphinic acid form A may be recrystallised by dissolution in a polar solvent or a mixture of polar solvents such as methanol, isopropanol or water or a mixture thereof. The solution is clear filtered and the filter is washed with the polar solvent used. The temperature is kept at room temperature, and an anti-solvent or a mixture of anti-solvents, for example acetonitrile, acetone, ethanol, isopropanol, ethylacetate or a mixture thereof are added during a period of 2 to 5 hours. The slurry is then stirred 5 to 12 hours. The formed product is filtered off and washed with the used anti-solvent and dried in vacuum.

The compound 3-Amino-2-fluoropropyl phosphinic acid, (2R)-3-Amino-2-fluoropropyl phosphinic acid as well as (2S)- 3-Amino-2-fluoropropyl phosphinic acid, may be presented in the form of internal salts. It can also form acid addition salts and salts with bases. Such salts are particularly pharmaceutically acceptable acid addition salts, as well as pharmaceutically acceptable salts formed with bases. Suitable acids for the formation of such salts include, for example, mineral acids such as hydrochloric, hydrobromic, sulfuric, or phosphoric acid or organic acids such as sulfonic acids and carboxylic acids. Salts with bases are, for example, alkali metal salts, e.g. sodium or potassium salts, or alkaline earth metal salts, e.g. calcium or magnesium salts, as well as ammonium salts, such as those with ammonia or organic amines. The salts may be prepared by conventional methods. (2R)-(3-Amino-2-fluoropropyl)phosphinic acid form A and its preparation is disclosed in WO 01/42252. PCT/SE2008/051491 discloses a process for the preparation of (2R)-(3- Amino-2-fluoropropyl)phosphinic acid form A. PCT/SE2008/051492 discloses (2R)-(3- Amino-2-fluoropropyl)phosphinic acid form B and its preparation. The disclosure of these documents are hereby incorporated by reference.

Preparation of the formulations - general process

A core of a solid material of a size of from 100-700 μm is coated with the compound 3-Amino-2-fluoropropyl phosphinic acid by a spray-crystallization process. A solution containing said compound is sprayed onto the solid material and the solvent is evaporated. The amount of the compound is in the range of from 0.4 to 0.99 mg per mg of the pellet.

Examples of core materials are: the compound 3-Amino-2-fluoropropyl phosphinic acid or a pharmaceutically and pharmacologically acceptable salt thereof; the compound (2R)-3- Amino-2-fluoropropyl phosphinic acid or a pharmaceutically and pharmacologically acceptable salt thereof; the compound (2S)-3-Amino-2-fluoropropyl phosphinic acid or a pharmaceutically and pharmacologically acceptable salt thereof; microcrystalline cellulose such as Celphere CP-203 (200-300 μm), Celphere CP-305 (300-500 μm) or Celphere 507 (500-700 μm); silicon dioxide (sand); or sucrose.

The release profile is thereafter adjusted by forming a film of a polymer mixture, such as a mixture of ethylcellulose (EC) and hydroxypropylcellulose (HPC).

In one aspect of the invention, the release profile is adjusted by forming a film of a polymer mixture selected from any one of: • polymethyl methacrylate-ethylacrylate copolymer dispersion / polyethylene glycol - polyvinyl alcohol copolymer (mixture of Eudragit^® NE30D/ Kollicoat^® IR);

• polymethyl methacrylate-ethylacrylate copolymer dispersion / polyethylen glycol - polyvinyl alcohol copolymer (Eudragit^® NM30D/ Kollicoat^® IR); and • polymethyl methacrylate-ethylacrylate copolymer dispersion)/ sodium stearyl fumarate (Eudragit^® NM30D/ Pruv^®).

Ethylcellulose (EC) is commercially available as Ethocel^™ from Dow Chemical Company. Hydroxypropylcellulose (HPC) is commercially available as Klucel from Aqualon (Hercules). Eudragit^®NE 30 D is an aqueous dispersion of a neutral co-polymer based on ethyl acrylate and methyl methacrylate and is commercially available from Evonik Industries Rohm GmbH. Eudragit^® NM 30 D is an aqueous dispersion of a neutral copolymer based on ethyl acrylate and methyl methacrylate and is commercially available from Evonik Industries Rohm GmbH. Kollicoat^® IR is commercially available from BASF.

Pruv^®is sodium stearyl fumarate which is commercially available from JRS Pharma GmbH.

One embodiment of the present invention, is a pharmaceutical formulation as herein described, wherein the polymer mixture is ethylcellulose (EC) and hydroxypropylcellulose (HPC) in a ratio of 78-65/ 22-35 % by weight.

Yet an embodiment of the invention, is a pharmaceutical formulation as herein described, wherein the polymer mixture is polymethyl methacrylate-ethylacrylate copolymer dispersion / polyethylene glycol - polyvinyl alcohol copolymer (mixture of Eudragit^® NE30D/ Kollicoat^® IR) wherein the ratio between each polymer is 75-80/ 25-20 % by weight. Yet an embodiment of the invention, is a pharmaceutical formulation as herein described, wherein the polymer mixture is polymethyl methacrylate-ethylacrylate copolymer dispersion / polyethylen glycol - polyvinyl alcohol copolymer (Eudragit^® NM30D/ Kollicoat^® IR), wherein the ratio between each polymer is 75-80/ 25-20 % by weight.

Still an embodiment of the invention, is a pharmaceutical formulation as herein described, wherein the polymer mixture is polymethyl methacrylate-ethylacrylate copolymer dispersion)/ sodium stearyl fumarate (Eudragit^® NM30D/ Pruv^®), wherein the ratio between each polymer is 75-80/ 25-20 % by weight.

The amount of film-forming polymer mixture may be from 10-50 % by weight of the final coated product.

Step 1 , Coating of a core to provide a pellet

A solution of the compound 3-Amino-2-fluoropropyl phosphinic acid, (2R)-3-Amino-2- fluoropropyl phosphinic acid, or (2S)-3-Amino-2-fluoropropyl phosphinic acid,or a pharmaceutically and pharmacologically acceptable salt thereof, is prepared in a concentration of from 38-60 % w/w, such as from 48-58 % w/w. Examples of solvents that may be used in accordance with the invention are water or an alcohol such as ethanol, or a mixture thereof. The solution is held at a temperature of from 20⁰C - 60 ⁰C. The solution of said compound is sprayed onto the core material in a fluidised bed drier such as Aeromatic MPl or Glatt GPCG at a temperature of from 30-100⁰C, such as from 35-8O⁰C, or from 45- 6O⁰C, for example from 30 - 500 minutes.

Examples of batch sizes useful in accordance with the invention are from 1O g and up to and including 400 kg.

The crystallization of the compound 3-Amino-2-fluoropropyl phosphinic acid, (2R)-3- Amino-2-fluoropropyl phosphinic acid, or (2S)-3-Amino-2-fluoropropyl phosphinic acid, onto the core may be initiated or effected with or without seeding with crystals of said compound and can be performed in one step or be divided in several sub-batches. For a batch size of 1 kg, a pump speed of from 0.5 - 5 g/min may be suitable. The pump speed is kept at this lower range for the first 30 minutes to allow initiation of crystallisation. The pump speed is thereafter increased.

Step 2, Polymer coating of pellets from step 1

The pellets formed in step 1 are coated with a polymer mixture as described in the specification and claims. The polymer mixture is dissolved in a solvent such as water, a ketone such as acetone or methyl ethylketone or an alcohol such as ethanol and/or mixtures thereof. The solution is sprayed onto the pellets in a fluidised bed equipment such as

Aeromatic MPl or Glatt GPCG at a temperature of from 35-70⁰C, such as from 35-50⁰C. The solution is sprayed onto the pellets for a sufficient period of time, such as from 30 to 600 minutes. The time required is dependent on the batch size and the desired thickness of the polymer film. The batch size may be from 10 g up to 400 kg.

Step 3, Capsule filling

The final coated product comprising the compound 3-Amino-2-fluoropropyl phosphinic acid, (2R)-3-Amino-2-fluoropropyl phosphinic acid, or (2S)-3-Amino-2-fluoropropyl phosphinic acid, prepared according to step 2, may be filled into a capsule. Examples of capsule material that may be used in accordance with the invention are hydroxypropyl methylcellulose or gelatine.

In an alternative embodiment of the invention, a solid particle as described above and compressed into a unit having a diameter of approximately 1, 2, 3 or 4 mm (a "pellet"), a small tablet. Determination of the In vitro drug release profile

The wording "//? vitro drug release profile" as used herein, is defined as the percentage compound dissolved at different time points, in relation to the total amount of compound comprised within each formulation that is tested. Release of the compound 3-Amino-2- fluoropropyl phosphinic acid, (2R)-3-Amino-2-fluoropropyl phosphinic acid, or (2S)-3- Amino-2-fluoropropyl phosphinic acid of a formulation is performed in 900 ml phosphate buffer at a pH of 6.8, using an USP dissolution apparatus II at 37°C and rotational speed 75 rpm. During the dissolution analysis, samples are collected at different time points. The compound 3-Amino-2-fluoropropyl phosphinic acid, (2R)-3-Amino-2-fluoropropyl phosphinic acid, or (2S)-3-Amino-2-fluoropropyl phosphinic acid is derivatised by ortho- phthaldialdehyde and 3-mercaptopropionic acid to form an UV absorbing derivative. The reaction is carried out on-line in an autoinjector of the chromatographic system. The analysis is performed by Liquid Chromatography with UV detection at 334 nm on an octadecylsilyl (C- 18) column. The compound 3-Amino-2-fluoropropyl phosphinic acid, (2R)-3-Amino-2-fluoropropyl phosphinic acid, or (2S)-3-Amino-2-fluoropropyl phosphinic acid, is quantified by external standard methodology

Determination of In vivo blood plasma concentration

The wording "//? vivo blood plasma concentration" as used herein, is defined as the concentration of the compound in blood plasma at different time points, after administration of a pharmaceutical formulation as described and claimed herein. At different time points after administration, blood samples (2 mL) for the determination of the compound 3-amino-2-fluoropropyl phosphinic acid, (2R)-3-Amino-2-fluoropropyl phosphinic acid, or (2S)-3-Amino-2-fluoropropyl phosphinic acid in plasma are collected into lithium heparin tubes and mixed carefully. Samples are centrifuged for 10 minutes at approximately 4°C at a relative centrifugal force of approximately 150Og. Following centrifugation the plasma is transferred into a 4.5 mL Cryovial™ tube and immediately frozen in an upright position. The frozen samples are stored at -18°C or lower until analysis. Samples for the determination of the compound 3-amino-2-fluoropropyl- phosphinic acid, (2R)-3-Amino-2-fluoropropyl phosphinic acid, or (2S)-3-Amino-2- fluoropropyl phosphinic acid, in plasma are analysed by using liquid chromatography and mass spectrometric detection after sample preparation with protein precipitation.

The invention will now be illustrated by the following non-limited examples.

EXAMPLES

Example 1 Preparation of (2R)-(3-Amino-2-fluoropr()pyl)phosphinic acid, Form A

320 g (1.11 moles) (2R)-3-[(tert-butoxycarbonyl)amino]-2-fluoro-propyl phosphinic acid ammonium salt dissolved in methanol (960 ml, 23.72 moles ) was treated with sulphuric acid (105.43 ml, 1.90 moles) at 55°C. After complete reaction, the reaction mixture was cooled to 30⁰C and pH was adjusted to approximately 5 by addition of ammonium acetate dissolved in methanol (180 g, 2.34 moles, 420 ml methanol). During the pH-adjustment ammonium sulphate remaining ammonium acetate and other salts precipitated. The neutralised reaction mixture was clear filtrated. Isopropanol (3.84 L, 50.23 moles) was added at 50⁰C and (2R)-(3-Amino-2-fluoropropyl)phosphinic acid, Form A, crystallised. The slurry was cooled to 0⁰C. The crystals were isolated and dried under vacuum.

¹H-NMR (400 MHz, D₂O): δl.93 (1 H, m), 2.13 (1 H, m), 3.31 (2 H, m), 5.14 (1 H, dm, J=50 Hz), 7.07 (1 H, d, J=528 Hz).

The crystals were analysed by X-ray powder diffraction (XRPD). The diffractogram of form A shows the following d- values given in Angstrom and relative intensities:

The relative intensities are presented by the following definitions.

The relative intensities were derived from diffractograms measured with variable slits. Example 2

Preparation of (2RH3-Amino-2-fluoropropyr)phosphinic acid, form B

40 g of (2R)-(3-Amino-2-fluoropropyl)phosphinic acid form A, was added to 15OmL methanol and 65 mL water. The slurry was heated to 40⁰C until all was dissolved. 320 mL of acetone was added to the solution over 10 hrs. The slurry was stirred at 40⁰C for 33 hours. Then obtained crystals were filtered and dried in vacuum at 40⁰C overnight. 36.67 g of (2R)-(3-Amino-2-fluoropropyl)phosphinic acid, form B, was obtained after drying. ¹H-NMR (400 MHz, D₂O): δl.95 (1 H, m), 2.15 (1 H, m), 3.33 (2 H, m), 5.16 (1 H, dm, J=50 Hz), 7.08 (1 H, d, J=528 Hz).

The crystals were analysed by X-ray powder diffraction (XRPD). The diffractogram of form B shows the following d- values given in Angstrom and relative intensities:

The relative intensities are presented by the following definitions:

The relative intensities are derived from diffractograms measured with variable slits.

Example 3

Composition of (2R)-(3-amino-2-fluoropr()pyl)phosphinic acid oral solution 2 mg/mL

A formulation comprising the following ingredients was prepared:

An oral solution was prepared by dissolving citric acid monohydrate, sodium citrate dihydrate, disodium edetate, sodium chloride and (2R) -(3-amino-2- fluoropropyl)phosphinic acid, Form A, in purified water. Purified water was added to the final volume. The solution was sterile filtered and filled into colourless glass vials. The vials were sealed with rubber stoppers and secured with aluminium caps.

Example 4

Composition of (2R)-(3-amino-2-fluoropr()pyl)phosphinic acid modified release capsules 100 mg

A formulation comprising the following ingredients was prepared:

An aqueous solution of 225 g of the compound 3-Amino-2-fluoropropyl phosphinic acid in 244 g water was prepared. The solution was held at 20⁰C and sprayed at a pump speed of 1 g solution/min for the first 30 minutes and thereafter up to 10 g solution/min for another 60 minutes onto 225 g microcrystalline cellulose (MCC) powder spheres (Celphere CP-305 (300-500 μm)) in a fluidised bed drier (Aeromatic MPl, temperature air inlet about 80⁰C, temperature product container 65°C, fluidising speed 80 m³/h and an atomizer pressure of 2.7-2.8 bar) giving 50 % (w/w) active drug/MCC pellets. The process was repeated by spraying a solution of 350 g of the compound 3-Amino-2-fluoropropyl phosphinic acid in 379 g water onto the prepared 50 % (w/w) drug/MCC mixture obtaining a 75 % (w/w) active drug/MCC product. The process was further repeated (twice) until a 93.8 % (w/w) drug/MCC product was obtained (990 g) using the same process parameters. The process could be made in one or several steps depending on the batch size.

250 g of the pellets formed (990 g) containing 938 mg/g of the compound 3-Amino-2- fluoropropyl phosphinic acid were coated with a solution of 51 g ethyl cellulose 10 cP (EC) and 24 g hydroxypropyl cellulose (HPC) dissolved in 863 g 95 % ethanol in a fluidised bed equipment (Aeromatic MPl) at a temperature of product container of 45⁰C with a pump speed from initially 5 g solution/min and then successively up to 25 g solution/min for 60 minutes. The coated pellets contained 721 mg of compound according to examples 1-2 per gram of final formulation. 12O g of the final coated productwere filled into hydroxypropyl methylcellulose capsules (hard, size 0, white).

Example 5

A formulation comprising the following ingredients was prepared:

Pellets containing 93.8 % of the compound 3-Amino-2-fluoropropyl phosphinic acid and 6.2 % microcrystalline cellulose was prepared according to example 4. The pellets (250 g) were coated with a solution of 58.5 g ethyl cellulose 10 cP (EC) and 16.5 g hydroxypropyl cellulose (HPC) dissolved in 863 g 95 % ethanol in a fluidised bed equipment (Aeromatic MPl) at a temperature of the product container of 45 ⁰C with a pump speed initially 5 g solution/min and then successively up to 25 g solution/min for 40 minutes. The coated pellets contained 721 mg of the compound 3-Amino-2-fluoropropyl phosphinic acid per gram of final formulation. 12O g of the final coated product was filled into hydroxypropyl methylcellulose capsules (hard, size 0, white).

Example 6 Composition of (2RH3-amino-2-fluoropropyr)phosphinic acid modified release capsules 100 mg

A formulation comprising the following ingredients was prepared:

Pellets containing 93.8 % of the compound 3-Amino-2-fluoropropyl phosphinic acid and 6.2 % microcrystalline cellulose was prepared according to example 4. These pellets (250 g) containing 93.8 % of the compound 3-Amino-2-fluoropropyl phosphinic acid and 6.2 % microcrystalline cellulose were coated with a solution of 67.5 g ethyl cellulose 10 cP (EC) and 7.5 g hydroxypropyl cellulose (HPC) dissolved in 863 g 95 % ethanol in a fluidised bed equipment (Aeromatic MPl) at a temperature of the product container of 45⁰C with a pump speed of initially 5 g solution/min and then successively up to 25 g solution/min for 55 minutes. The coated pellets contained 721 mg of the compound 3-Amino-2- fluoropropyl phosphinic acid per gram of final formulation. 175 g of the final coated product was filled into hydroxypropyl methylcellulose capsules (hard, size 0, white).

Example 7

Composition of (2RH3-amino-2-fluoropropyr)phosphinic acid modified release capsules 100 mg

A formulation comprising the following ingredients was prepared:

An aqueous solution of 2500 g of the compound 3-Amino-2-fluoropropyl phosphinic acid in 2045 g water was prepared. The solution was held at 40⁰C and sprayed at a pump speed of about 1 g solution/min for the first 30 minutes and thereafter up to 65 g solution /min for another 105 minutes onto 1200 g microcrystalline cellulose (MCC) powder spheres (Celphere CP-203 (200-300 μm)) in a fluidised bed drier (Glatt GPCG, temperature of the product container about 45°C, fluidising speed 60-75 m /h and an atomizer pressure of 2.5 bar) giving 68 % (w/w) active drug/MCC pellets. The process was further repeated (twice) until a 96 % (w/w) drug/MCC product was obtained using the same process parameters. The process could be made in one or several steps depending on batch sizes.

150O g of pellets containing 96 % of the compound 3-Amino-2-fluoropropyl phosphinic acid and 4 % microcrystalline cellulose was prepared. These pellets were coated with a solution of 510 g ethyl cellulose 10 cP (EC) and 240 g hydroxypropyl cellulose (HPC) dissolved in 8625 g 95 % ethanol in a fiuidised bed equipment (Glatt GPCG) at a temperature of 45⁰C with a pump speed of initially 4 g solution/min and then successively up to 40 g solution/min for 330 minutes. The coated pellets contained 640 mg of the compound 3-Amino-2-fluoropropyl phosphinic acid per gram of final coated formulation.

Example 8

Composition of (2RH3-amino-2-fluoropropyr)phosphinic acid modified release capsules 60 mg - large scale manufacturing

A formulation comprising the following ingredients was prepared:

An aqueous solution of 120 kg of the compound 3-Amino-2-fluoropropyl phosphinic acid in 111 kg water was prepared. The solution was held at 50-60 ⁰C and sprayed onto 30 kg microcrystalline cellulose spheres (Celphere CP-203 (150-300 μm)) in a fluidised bed drier (Glatt GPCG 120 spray 1 FBD, inlet air temperature 80-100 ⁰C, fluid bed product temperature 45-55 ⁰C, fluidising air flow 1000-2500 Nm /h and an atomizing air pressure of 2-4 bar) giving 80 % (w/w) active drug/MCC pellets. The process could be made in one or several steps depending on the batch size.

134 kg of the pellets formed, containing 800 mg/g of the compound 3-Amino-2- fluoropropyl phosphinic acid, were coated with a solution of 39 kg ethyl cellulose 10 cP (EC) and 15 kg hydroxypropyl cellulose (HPC) dissolved in 262 kg 95 % ethanol in a fluidised bed equipment (Glatt GPCG 200 CC7, inlet air temperature 80-90 ⁰C, fluidising air flow 1750-1850 Nm³/h and an atomizing air pressure of 1-4 bar. The coated pellets were sieved after coating to remove potential lumps or agglomerated pellets. The sieved material was deairated to decrease the level of remaining ethanol. Before capsule filling, 178 kg coated, sieved and deairated pellets were mixed with 1 kg sodium stearyl fumarate. 40 kg of these pellets were filled into hydroxypropyl methylcellulose capsules (hard, size 1, white).

Example 9

A clinical study in healthy volunteers was performed. Oral single 100 mg doses according to example 3 were given and compared to capsules prepared according to examples 4 to 7. An oral fractionated solution according to example 3 was given with 30 minutes between fractions (5 mg, 5 mg, 30 mg, 60 mg, 400 mg). Determination of the In vivo blood plasma concentration for a pharmaceutical formulation of Examples 4, 5 and 6 above.

At different time points after administration, blood samples (2 mL) for the determination of the compound (2R)-3-amino-2-fluoropropyl phosphinic acid in plasma were collected into lithium heparin tubes and mixed carefully. Samples were centrifuged for 10 minutes at approximately 4°C at a relative centrifugal force of approximately 150Og. Following centrifugation the plasma was transferred into a 4.5 mL Cryovial™ tube and immediately frozen in an upright position. The frozen samples were stored at -18°C or lower until analysis. Samples for the determination of the compound (2R)-3-amino-2-fluoropropyl phosphinic acid in plasma were analysed by using liquid chromatography and mass spectrometric detection after sample preparation with protein precipitation.

Table A below shows:

(i) The percentage of study subjects experiencing paraesthesia in the study, when administered with an oral solution of the compound (2R)-3-Amino-2-fluoropropyl- phosphinic acid as described in Example 3 above (100 mg and 500 mg respectively), as well as subjects which were administered with an MR capsule formulation, each comprising 100 mg of the compound (2R)-3-Amino-2-fluoropropyl phosphinic acid, as described in Examples 4, 5 and 6 respectively.

(ii) The concentration of (2R)-3-Amino-2-fluoropropyl phosphinic acid in blood plasma after 15 minutes and after 30 minutes from administration, respectively, expressed as the percentage of C_maX-. Table A

Limit of quantification (LOQ) was 0.03 μM., * Average % Cmax

Reversible and short lasting paresthesia perceived as tingling sensations was observed after administration of (2R)-(3-amino-2-fluoro propyl)phosphinic acid as a single oral solution. The reported paresthesia occured with a mean time of onset of 8 minutes after dosing.

In vitro determination of the drug release profile

Release of the compound (2R)-3-Amino-2-fluoropropyl phosphinic acid of the formulation was performed in 900 ml phosphate buffer at a pH of 6.8 by using a USP dissolution apparatus II at a temperature of 37°C and at a rotational speed of 75 rpm. During the dissolution analysis, samples were collected at different time points. The compound (2R)- 3-Amino-2-fluoropropyl phosphinic acid is derivatised by ortho-phthaldialdehyde and 3- mercaptopropionic acid to form an UV absorbing derivative. The reaction was carried out on-line in an autoinjector of the chromatographic system. The analysis was performed by Liquid Chromatography with UV detection at 334 nm on an octadecylsilyl (C- 18) column. The compound (2R)-3-Amino-2-fluoropropyl phosphinic acid was quantified by external standard methodology. Table B below shows:

The in vitro amount of compound dissolved in the formulations comprising (2R)-3-Amino- 2-fluoropropyl phosphinic acid as described in Examples 4, 5, 6, 7 and 8, respectively, were measured 15 minutes, 30 minutes, 60 and 120 minutes after dissolution initiation respectively, expressed as the percentage compound dissolved in relation to the total amount of (2R)-3-Amino-2-fluoropropyl- phosphinic acid comprised within each formulation that was tested.

Table B

*mean value.

Example 10

Composition of (2RH3-amino-2-fluoropropyr)phosphinic acid immediate release capsules 65 mg

A formulation comprising the following ingredients was prepared:

An aqueous solution of 480 g of the compound 3-Amino-2-fluoropropyl phosphinic acid in 443 g water was prepared. The solution was held at about 50 ⁰C and sprayed onto 120 g microcrystalline cellulose spheres (Celphere CP-203 (150-300 μm)) in a fluidised bed drier (Gandalf 3, inlet air temperature about 60-72 ⁰C, outlet air temperature 41-49 ⁰C, fluidising air flow 40 Nm³/h and an atomizing air pressure of 2-3 bar) giving 80 % (w/w) active drug/MCC pellets. The process could be made in one or several steps depending on the batch size.

59 g of the modified release pellets were filled into hydroxypropyl methylcellulose capsules (hard, size 0, white). Example 11

Composition of (2RH3-amino-2-fluoropropyr)phosphinic acid immediate release capsules 150 mg

A formulation comprising the following ingredients was prepared:

The pellets were prepared as described in Example 10 above. 135 g of the modified release pellets were filled into hydroxypropyl methylcellulose capsules (hard, size 0, white).

Example 12

Composition of (2RH3-amino-2-fluoropropyr)phosphinic acid modified release capsules 65 mg

A formulation comprising the following ingredients was prepared:

The pellets were prepared as described in Example 10 above.

400 g of the pellets formed, containing 800 mg/g of the compound 3-Amino-2- fluoropropyl phosphinic acid, were coated with a solution of 126 g ethyl cellulose 10 cP (EC) and 59 g hydroxypropyl cellulose (HPC) dissolved in 2129 g 95 % ethanol in a fluidised bed equipment (Gandalf 3, inlet air temperature about 70 ⁰C, outlet air temperaure of 44 - 52⁰C, fluidising air flow 35 Nm³/h and an atomizing air pressure of 2-3 bar. 86 g of the final coated product were filled into hydroxypropyl methylcellulose capsules (hard, size 0, white). Example 13

Composition of (2R)-(3-amino-2-fluoropr()pyl)phosphinic acid modified release capsules 150 mg

A formulation comprising the following composition was prepared:

An aqueous solution of 480 g of the compound 3-Amino-2-fluoropropyl phosphinic acid in 443 g water was prepared. The solution was held at about 50 ⁰C and sprayed onto 120 g microcrystalline cellulose spheres (Celphere CP-203 (150-300 μm)) in a fluidised bed drier (Gandalf 3, inlet air temperature about 60-70 ⁰C, outlet air temperature 41-49 ⁰C, fluidising air flow 40 Nm³/h and an atomizing air pressure of 2-3 bar) giving 80 % (w/w) active drug/MCC pellets. The process could be made in one or several steps depending on the batch size.

The pellets were coated with the polymer film mixture as described in Example 12 above.

197 g of the final coated product were filled into hydroxypropyl methylcellulose capsules (hard, size 0, white). Example 14

Composition of (2RH3-amino-2-fluoropropyr)phosphinic acid modified release capsules 150 mg

A formulation comprising the following composition was prepared:

An aqueous solution of 480 g of the compound 3-Amino-2-fluoropropyl phosphinic acid in 443 g water was prepared. The solution was held at about 50 ⁰C and sprayed onto 120 g microcrystalline cellulose spheres (Celphere CP-203 (150-300 μm)) in a fluidised bed drier (Gandalf 3, inlet air temperature about 60-73 ⁰C, outlet air temperature 41-49 ⁰C, fluidising air flow 40 Nm³/h and an atomizing air pressure of 2-3 bar) giving 80 % (w/w) active drug/MCC pellets. The process was repeated by spraying a solution of 480 g of the compound 3-Amino-2-fluoropropyl phosphinic acid in 443 g water onto the prepared 80 % (w/w) drug/MCC mixture onto 12O g microcrystalline cellulose spheres (Celphere CP-203 (150-300 μm) obtaining a 96 % (w/w) active drug/MCC product. The process could be made in one or several steps depending on the batch size. 400 g of the pellets formed, containing 960 mg/g of the compound 3-Amino-2- fluoropropyl phosphinic acid, were coated with a solution of 120 g ethyl cellulose 10 cP (EC) and 56 g hydroxypropyl cellulose (HPC) dissolved in 2203 g 95 % ethanol in a fluidised bed equipment (Gandalf 3, inlet air temperature about 70 ⁰C, outlet air temperaure of 44-55 ⁰C, fluidising air flow 35 Nm³/h and an atomizing air pressure of 2-3 bar. 161 g of the final coated product were filled into hydroxypropyl methylcellulose capsules (hard, size 0, white).

Example 15 MR Formulation study - ClinicalTrials.gov identifier NCT00688402

A clinical phase I study in healthy volunteers to compare the development of paraesthesiae after administration of different formulations of (2R)-3-Amino-2-fluoropropyl phosphinic acid (expressed as "compound" in Table D below) with different release rates was performed.

Seventy (70) subjects were enrolled in the study, 48 subjects were randomized and 47 subjects completed the study.

This was a double blind, randomized, cross-over study. The study was planned to randomize 48 healthy volunteers (hereafter referred to as subjects) in order to have at least 40 evaluable subjects. Each subject received single doses of 4 of the 5 possible treatments in a four- way cross-over design with wash-out periods of at least 5 days between dose administrations.

Thirty (30) male and 18 female subjects were included in the study. The mean age was 24.4 years (range 18-39 years). The subjects were divided into 2 groups, where Group A (24 randomized subjects) had PK samples drawn for 36h post-dose and Group B (24 randomized subjects) had PK samples drawn for 4h post-dose. The consignment to groups was not blinded. The treatment allocation was known to AstraZeneca Research and development (R&D) personnel but blinded to the clinical research organisation (CRO), the investigational site and the subjects.

The 5 possible treatments in the study are listed below:

• IR 65 mg (IR pellets in a capsule with <0.5h for 80% release) • IR 150 mg (IR pellets in a capsule with <0.5h for 80% release)

• MR Ih 65 mg (MR pellets in a capsule with Ih for 80% release)

• MR Ih 150 mg (MR pellets in a capsule with Ih for 80% release) • MR 2h 150 mg (MR pellets in a capsule with 2h for 80% release)

The wording "IR 65 mg" as used herein, is a pharmaceutical immediate release capsule formulation comprising 65 mg of the compound (2R)-3-Amino-2-fluoropropyl phosphinic acid, wherein at least 80 % of said compound is released in vitro within 30 minutes from the time of administration.

The wording "IR 150 mg" as used herein, is a pharmaceutical immediate release capsule formulation comprising 150 mg of the compound (2R)-3-Amino-2-fluoropropyl phosphinic acid, wherein at least 80 % of said compound is released in vitro within 30 minutes from the time of administration.

The wording "MR 1 h 65 mg" as used herein, is a pharmaceutical modified release capsule formulation comprising 65 mg of the compound (2R)-3-Amino-2-fluoropropyl phosphinic acid, wherein approximately 80 % of said compound is released in vitro within 1 hour/ 60 minutes from the time of administration.

The wording "MR 1 h 150 mg" as used herein, is a pharmaceutical modified release capsule formulation comprising 150 mg of the compound (2R)-3-Amino-2-fluoropropyl phosphinic acid, wherein approximately 80 % of said compound is released in vitro within 1 hour/ 60 minutes from the time of administration.

The wording "MR 2 h 150 mg" as used herein, is a pharmaceutical modified release capsule formulation comprising 150 mg of the compound (2R)-3-Amino-2-fluoropropyl phosphinic acid, wherein approximately 80 % of said compound is released in vitro within 2 hours/ 120 minutes from the time of administration. Table C

All doses of the investigational product (i.e. a formulation of the compound (2R)-3-Amino- 2-fluoropropyl phosphinic acid according to Table C/ Examples 10, 11, 12, 13 and 14, were administered at the investigational site under the supervision of study personnel. All investigational products were administered in the morning with 240 mL tap water of room temperature. Subjects were fasting (no meals after 11 :00 pm the day before and no fluids within Ih before dose). The capsules were to be swallowed whole and were not to be divided, chewed or crushed. Water was allowed Ih after dosing. No additional fluids were allowed within 2h after drug intake and no meals were allowed until after 4h when a standardized lunch was served.

The occurrence of paraesthesiae was the primary pharmacodynamic outcome variable in the study. The subjects were asked "Have you felt any tingling sensation and/or sensation of heat and/or burning sensation since intake of investigational product?". The occurrence of paraesthesiae was recorded during 4hours after administration of the investigational product. If present, the reported sensation was classified with regard to time of onset, duration, character, location, intensity and level of discomfort. Paraesthesiae was rated according to a 7-grade scale:

1. None

2. Minimal

3. Mild 4. Moderate

5. Rather severe

6. Severe

7. Very severe

The intensity rating is defined as 1 = mild (awareness of sign or symptom, but easily tolerated); 2 = moderate (discomfort sufficient to cause interference with normal activities); and 3 = severe (incapacitating, with inability to perform normal activities).

Only paraesthesiae observations rated Moderate (4) or worse are deemed relevant from a patient compliance perspective.

The following results were obtained:

Example 16

In vitro determination of the formulation release profile

Release of the compound (2R)-3-Amino-2-fluoropropyl phosphinic acid for each of the formulations in the clinical study described in Example 10, 1, 12, 13 and 14 above, was performed in 900 ml phosphate buffer at a pH of 6.8 by using a USP dissolution apparatus II at a temperature of 37°C and at a rotational speed of 75 rpm. During the dissolution analysis samples were collected at time points described in the Table E below. The compound (2R)-3-Amino-2-fluoropropyl phosphinic acid was derivatised in a pre-column by orto-phtaldialdehyde and 3-mercaptopropionic acid on-line in an autoinjector of the chromatographic system. The analysis was performed by using an Agilent 110 liquid Chromatography system with UV detection at 334 nm on an octadecylsilyl (C- 18) column. The compound (2R)-3-Amino-2-fluoropropyl phosphinic acid was quantified by external standard methodology. Table D below shows:

The in vitro amount of compound dissolved in the formulations comprising (2R)-3-Amino- 2-fluoropropyl phosphinic acid, were measured 15 minutes, 30 minutes, 60 and 120 minutes after dissolution initiation respectively, expressed as the percentage compound dissolved in relation to the total amount of (2R)-3-Amino-2-fluoropropyl- phosphinic acid comprised within each formulation that was tested.

Table D

Claims

1. A pharmaceutical formulation comprising the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, or a pharmaceutically and pharmacologically acceptable salt thereof, said formulation having a release profile in vivo in human, such that

(iii) the maximum mean blood plasma concentration (C_max) of the compound 3-

Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is at least 1.3 μmol/1 and is obtained during 1.5-4.0 hours from the time of administration.

2. A pharmaceutical formulation according to claim 1, wherein the maximum mean blood plasma concentration (C_max) of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is at least 1.3 μmol/1, obtained during 1.5-3.5 hours from the time of administration.

3. A pharmaceutical formulation according to claim 2, wherein the maximum mean blood plasma concentration (C_max) of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is at least 1.3 μmol/1, obtained during 1.5-3.0 hours from the time of administration.

4. A pharmaceutical formulation according to any one of the preceding claims, said formulation having a release profile in vivo in human, such that

(i) up to 15 % of the maximum mean blood plasma concentration (C_max) but not more than 0.2 μM, of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is obtained within 15 minutes after administration; and

(ii) up to 40 % of the maximum mean blood plasma concentration (C_max) but not more than 0.5 μM, of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is obtained within 30 minutes after administration;

5. A pharmaceutical formulation comprising the compound 3-Amino-2-fluoropropyl- phosphinic acid or an enantiomer thereof, or a pharmaceutically and pharmacologically acceptable salt thereof, said formulation having a release profile in vitro, wherein

6. A pharmaceutical formulation according to claim 5, said formulation having a release profile in vitro, wherein

(ii) up to 65 % of the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof, is released within 30 minutes after immersion in an USPII bath.

7. A pharmaceutical formulation according to claim 5 or 6, said formulation having a release profile in vitro, wherein

8. A pharmaceutical formulation comprising

(i) a core having a size of from 100-700 μm;

(ii) said core being coated with from 0.4 to 0.99 mg of the compound 3-Amino-2- fluoropropyl phosphinic acid or an enantiomer thereof , or a pharmaceutically and pharmacologically acceptable salt thereof, calculated based on the compound in non-salt form of said compound per mg pellet;

(iii) a polymer film coating which is a polymer mixture, in an amount of from

10-50 % by weight of the final coated product.

9. A pharmaceutical formulation according to claim 8, wherein said polymer film coating is a mixture of ethylcellulose (EC) and hydroxypropylcellulose (HPC).

10. A pharmaceutical formulation according to claim 8, wherein said polymer film coating is selected from any polymer mixture of:

• polymethyl methacrylate-ethylacrylate copolymer dispersion / polyethylene glycol

- polyvinyl alcohol copolymer (mixture of Eudragit^® NE30D/ Kollicoat^® IR);

• polymethyl methacrylate-ethylacrylate copolymer dispersion / polyethylen glycol - polyvinyl alcohol copolymer (Eudragit^® NM30D/ Kollicoat^® IR); or

• polymethyl methacrylate-ethylacrylate copolymer dispersion)/ sodium stearyl fumarate (Eudragit^® NM30D/ Pruv^®).

11. A pharmaceutical formulation according to claim 9, wherein the ratio of ethylcellulose (EC) and hydroxypropylcellulose (HPC) is 78-65/ 22-35 % by weight.

12. A pharmaceutical formulation according to claim 10, wherein the ratio of each polymer mixture is 75-80/ 25-20 % by weight.

13. A pharmaceutical formulation according to any one of claims 1-12, wherein the compound 3-Amino-2-fluoropropyl phosphinic acid or an enantiomer thereof is administered via fractionated administration.

14. A capsule comprising a pharmaceutical formulation according to any one of claims 1-13.

15. A tablet comprising a pharmaceutical formulation according to any one of claims 1-13.

16. A unit dosage form comprising a pharmaceutical formulation according to any one of claims 1-13.

17. A pharmaceutical formulation according to any one of the preceding claims, wherein the compound is (2R)-3-Amino-2-fluoropropyl phosphinic acid.

18. A pharmaceutical formulation according to any one of claims 1-17, wherein the daily dose of (2i?)-(3-Amino-2-fluoropropyl)phosphinic acid or a pharmaceutically acceptable salt thereof, is up to 2200 mg per day.

19. A pharmaceutical formulation according to claim 18, wherein (2i?)-(3-Amino-2- fluoropropyl)phosphinic acid or a pharmaceutically acceptable salt thereof is administered in a dose of from 60 to 240 mg bid.

20. A method for the treatment or prevention of GERD, wherein a pharmaceutical formulation according to any one of claims 1-19 is administered to a subject in need of such treatment or prevention.

21. Use of a pharmaceutical formulation according to any one of claims 1 - 19, for the manufacture of a medicament for the treatment of GERD.

22. A pharmaceutical formulation according to any one of claims 1-19, for use in the treatment of GERD.

23. A pharmaceutical formulation according to any one of claims 1-19, for use as add-on therapy in symptom control in a partial responder to PPI therapy.