WO2019097120A1

WO2019097120A1 - New use and pharmaceutical dosage forms

Info

Publication number: WO2019097120A1
Application number: PCT/FI2018/050834
Authority: WO
Inventors: Frederic Dargelas; Juha Ellmen; Satu LAKIO; Heidi LEPPINEN; Toni SARAPOHJA; Elina TURUNEN; Mikko Vahteristo
Original assignee: Orion Corporation
Priority date: 2017-11-16
Filing date: 2018-11-15
Publication date: 2019-05-23

Abstract

The present disclosure relates to 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use in a method for the treatment of Parkinson's disease as well as to pharmaceutical dosage forms used in said method.

Description

NEW USE AND PHARMACEUTICAL DOSAGE FORMS

FIELD OF THE INVENTION

BACKGROUND OF THE INVENTION

4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is a catechol O-methyltransferase (COMT) inhibitor disclosed in WO 2013/175053.

Levodopa ((-)-L-alpha-amino-beta-(3,4-dihydroxybenzene)propanoic acid) is a commonly used drug in the treatment of Parkinson's disease (PD). It is commercially available as a combination with an aromatic amino acid decarboxylase (AADC) inhibitor, such as carbidopa ((-)-L-alpha-hydrazino-alpha-methyl-beta-(3,4-dihydroxybenzene)propionic acid

monohydrate) or benserazide hydrochloride (N-(DL-seryl)-N’-(2,3,4- trihydroxybenzyl)hydrazine hydrochloride). The combination of levodopa with carbidopa is sold under, for instance, the trademark

Sinemet®, and the combination of levodopa, carbidopa and the COMT inhibitor entacapone under the trademark Stalevo®.

Corvol et al (Annals of Neurology, Volume 69, No. 1, 1 11-118) discloses the influence of COMT Vall58Met polymorphism in homozygous (COMT™ and COMT^LL) patients on entacapone after a single dose administration in combination with Madopar®

(benserazidedevodopa).

The most effective therapy for symptom control in Parkinson's disease is levodopa therapy. However, with disease progression and long-term levodopa treatment, PD patients frequently experience motor complications, including wearing off symptoms, such as "end-of-dose wearing off' symptoms, "early morning dystonia" and "on/off fluctuations", and dyskinesia. During end-of-dose wearing off, the effect of a dose of a PD drug decreases (wears off), the drug concentration decreases in plasma and subsequently in the brain, and the severity of PD symptoms, e.g., bradykinesia, rigidity, and resting tremor, are increased before the next dose is taken. Partly related to the motor symptoms and partly to the autonomic dysfunction, a PD patient with "end-of-dose wearing off' or "on/off fluctuations" may experience poor gastrointestinal tract mobility and swallowing difficulties.

In addition to the symptoms relating to motor function, the wearing off symptoms may also include non-motor symptoms, such as anxiety and pain. The reasons for the fluctuation episodes are not completely understood but may be, in part, related to oscillating plasma levels of levodopa in turn leading to intermittent or pulsatile stimulation of striatial dopamine receptors in the brain. End-of-dose wearing off symptoms or on/off fluctuations comprise alternations between periods of relatively good mobility ("on" periods) and periods of relatively impaired motor function ("off periods) often associated with simultaneous non motor symptoms. Dyskinesia are involuntary movements in the body of a PD patient often associated with high maximum or peak concentrations (C_max) of a PD drug, such as levodopa.

Thus, there is a continuing need to improve the present levodopa therapies by striving towards more steady plasma levels of levodopa and subsequently more continuous dopaminergic stimulation. SUMMARY OF THE INVENTION

The present disclosure provides 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use in a method for the treatment of Parkinson's disease by a simultaneous or sequential administration to a patient of

(i) 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile in an amount ranging from 50 to 100 mg,

(ii) carbidopa in an amount ranging from 65 to 105 mg, and

(iii) levodopa in an amount ranging from 50 to 200 mg.

The present disclosure also provides an oral dosage form comprising

(ii) carbidopa in an amount ranging from 65 to 105 mg, and

(iii) levodopa in an amount ranging from 50 to 200mg.

In Parkinson's disease, the selective catechol O-methyltransferase (COMT) Vall58Met polymorphism (RS4860) is equally distributed in PD patients and modulates COMT activity, which can be high (Val/Val, COMT^HH), intermediate (Val/Met, COMT^HL), or low (Met/Met, COMT^LL). Patients that may benefit the most from the treatment and dosage form according to the invention are patients having high catechol O-methyltransferase activity (COMT™ patients) or intermediate activity (COMT™ patients). BRIEF DESCRIPTION OF THE DRAWING

Figure 1 : X-ray powder diffractogram of crystalline form II of 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile monohydrate obtained in Example 18.

DETAILED DESCRIPTION OF THE INVENTION

The inventors have surprisingly found that the COMT inhibitor 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile, when administered in combination with a carbidopa dose from 65 to 105 mg, dose dependently significantly increases the AUC_0-24h and also the minimum concentrations

of levodopa without significantly increasing its maximum

concentration

This leads to improved levodopa pharmacokinetics and metabolism and subsequently to improved control of PD symptoms and motor complications. Furthermore, the inventors have found that the said effect is more pronounced in PD patients having a high catechol O-methyltransferase activity (COMT™ ) or an intermediate activity (COMT™) than in PD patients having a low catechol O-methyltransferase activity.

Thus, when compared to Sinemet® IR (100 mg levodopa, 25 mg carbidopa), the treatment according to the invention (100 mg of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile, 65 mg of carbidopa and 100 mg of levodopa) doubles the levodopa AUC_0-24h and almost triples without significantly increasing Thus, the treatment decreased levodopa

fluctuation

( ) by 62 % (p < 0.0001) and increased and

by 105 % (p < 0.0001). Fevodopa

was increased by 24 % (p = 0.5). Furthermore, with the treatment according to the invention, the fluctuations of levodopa plasma concentrations, i.e. levodopa peak-through fluctuation for each dosing interval

decreased by more than

was increased by 36 % and

was increased by 15 % compared to Stalevo®, with a trend towards reduced

by 10 %.

Thus, the present disclosure provides 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use in a method for the treatment of Parkinson's disease by a simultaneous or sequential administration to a patient of

(ii) carbidopa in an amount ranging from 65 to 105 mg, and

(iii) levodopa in an amount ranging from 50 to 200 mg.

The present disclosure provides a method for the treatment of Parkinson's disease by a simultaneous or sequential administration to a patient in need of treatment of Parkinson's disease of

(ii) carbidopa in an amount ranging from 65 to 105 mg, and

(iii) levodopa in an amount ranging from 50 to 200 mg. The present disclosure provides the use of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa in a method for the manufacture of a medicament for the treatment of Parkinson's disease by a simultaneous or sequential administration to a patient of

(ii) carbidopa in an amount ranging from 65 to 105 mg, and

(iii) levodopa in an amount ranging from 50 to 200 mg.

The present disclosure also provides an oral dosage form comprising

(i) 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile in an amount ranging from 50 to 100 mg, (ii) carbidopa in an amount ranging from 65 to 105 mg, and

(iii) levodopa in an amount ranging from 50 to 200 mg.

In particular, the present disclosure provides an oral dosage form comprising

(i) 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile in an amount of 100 mg,

(ii) carbidopa in an amount ranging from 65 to 105 mg, and

(iii) levodopa in an amount ranging from 50 to 200 mg.

In one embodiment of the invention, the PD patient to be treated is a high catechol O- methyltransferase activity (COMT^HH) or an intermediate activity (COMT^HL) patient.

In one embodiment of the invention, the patient is a wearing off patient.

In one embodiment of the invention, the three active ingredients are administered to the PD patient in a repeated manner.

In one embodiment of the invention, carbidopa is present in an amount of 65 mg.

In one embodiment of the invention, 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is present in an amount of 100 mg.

In one embodiment of the invention, 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate having at least peaks at 20 of about 6.1° and 11.2° in an X-ray powder diffractogram.

In one embodiment of the invention, 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate having at least peaks at 20 of about 6.1° and 14.7° in an X-ray powder diffractogram.

In one embodiment of the invention, 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate having at least peaks at 20 of about 6.1°, 11.2°, 14.7°, 16.2°, 21.8°, 24.0°, 26.2° and 26.9° in an X- ray powder diffractogram.

In one embodiment of the invention, 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate characterized by an X-ray powder diffractogram substantially as illustrated in Figure 1. In one embodiment of the invention, 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate containing less than 25 % by weight of other 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile solvates and crystalline forms thereof.

In one embodiment of the invention, 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate containing less than 10 % by weight of other 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile solvates and crystalline forms thereof

In one embodiment of the invention, 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate containing less than 6 % by weight of other 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile solvates and crystalline forms thereof

In one embodiment of the invention, 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate containing less than 4 % by weight of other 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile solvates and crystalline forms thereof.

In one embodiment of the invention, levodopa is present in an amount of 50 mg, 100 mg, 150 mg or 200 mg.

In one embodiment of the invention, the treatment comprises administering an oral solid dosage form.

In one embodiment of the invention, the oral dosage form is a combination dosage form.

In one embodiment of the invention, the oral dosage form is a capsule

In one embodiment of the invention, the oral dosage form is a tablet.

In one embodiment of the invention, 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile and carbidopa are in the same granules. In one embodiment of the invention, the total drug load of 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile and carbidopa in the granules is from 60 to 95 w/w % or from 70 to 85 w/w % or from 80 to 85 w/w %.

In one embodiment of the invention, levodopa is in a pellet.

In one embodiment of the invention, the pellet is coated.

In one embodiment of the invention, the pellet is uncoated.

In one embodiment of the invention, levodopa is in a granule.

In one embodiment of the invention, the drug load of levodopa in the pellet is from 60 to 90 w/w % or from 70 to 80 w/w % or from 70 to 75 w/w %.

A high drug load of granules and/or pellets is considered to be preferred, especially when the dosage form is a capsule as patients suffering from Parkinson^'s disease have often swallowing problems.

In one embodiment of the invention, the dosage form is an immediate release dosage form with regard to 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile and carbidopa.

In one embodiment of the invention, the dosage form is immediate release or slightly modified release dosage form with regard to levodopa.

It is to be understood that the amounts and ranges mentioned in this disclosure apply to all embodiments disclosed herein irrespective of whether methods (i.e. compounds for use in methods for the treatment or methods for the manufacture) or dosage forms are concerned.

A person skilled in the art recognizes that the position of peaks in X-ray powder

diffractograms can be subject to variation of ±0.2° 20 depending on various factors, such as temperature, concentration and instrumentation used. Therefore, the position of peaks is referred to herein as being at“about” specific values.

Polymorphic purity can be assessed with a method known in the art. Suitable methods include, but are not limited to, gas chromatography, column chromatography, liquid chromatography, high-pressure liquid chromatography, thin layer chromatography, mass spectrometry and high-resolution mass spectrometry.

Definitions

4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa, when used in the context of this disclosure also include pharmaceutically acceptable salts, hydrates or prodrugs (including esters) thereof.

The term "pharmaceutically acceptable salt" refers to a salt of a compound that is

pharmaceutically acceptable and possesses the desired pharmacological activity of the parent compound. Representative examples of pharmaceutically acceptable salts of 4,5-dihydroxy-2- (4-methylbenzyl)isophthalonitrile include, but are not limited to, potassium and sodium salts.

The term "ester" refers to an ester of a compound that is pharmaceutically acceptable and possesses the desired pharmacological activity of the parent compound. Such esters may be prepared by known methods using pharmaceutically acceptable acids that are conventional in the field of pharmaceuticals. Non-limiting examples of these esters include esters formed with aliphatic or aromatic alcohols. Representative examples of pharmaceutically acceptable esters include, but are not limited to, methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec- butyl, tert-butyl, and benzyl esters.

The term "prodrug" refers to a derivative of a drug substance which releases said active parent drug substance in vivo when such prodrug is administered to a patient. There are several publications disclosing different prodrugs of levodopa, for instance, EP 0 309 827 Bl, WO 2005/121069, WO 2007/067495, WO 02/28882, WO 2005/121070, WO

2006/056604, WO 2008/076458, WO 2008/079387, WO 2009/022098, WO 2009/101616, US 2009/0285888, WO 2009/156466, WO 2010/103273, WO 2012/079072, US

2013/0245074, WO 2014/139161, WO 2016/065019, and WO 2017/184871. Also, various carbidopa prodrugs have been disclosed e.g. in GB 940,596, WO 2004/052841, WO

2016/065019, and WO 2017/184871.

The term "treatment of Parkinson's disease" refers to relieving and/or delaying the worsening of one or more of the symptoms and/or motor complications related to idiopathic Parkinson's disease, e.g. bradykinesia, rigidity, and resting tremor. The term "simultaneous administration" refers to administration of the disclosed drug substances at the same time in separate formulations or as a combination formulation, i.e. in a single dosage form.

The term "sequential administration" refers to administration of the disclosed drug substances one after the other, i.e. not at the same time, in two or more separate dosage forms, for example, 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile may be administered as a separate dosage form and levodopa and carbidopa may be administered in a combination formulation. If the disclosed drug substances are administered sequentially, then typically administration of the last drug substance is begun an hour or less, generally 30 minutes or less, after administration of the first drug substance is begun.

The term "COMT^HH patient" is a PD patient with a homozygous polymorphic genotype having a high catechol O-methyltransferase enzyme activity.

The term "COMT^HL patient" is a PD patient with a heterozygous polymorphic genotype having an intermediate catechol O-methyltransferase enzyme activity. The term "COMT^LL patient" is a PD patient with a homozygous polymorphic genotype having a low catechol O-methyltransferase enzyme activity.

The term“wearing off patient” refers to a patient experiencing symptoms of end-of-dose wearing off, i.e. shortened duration of the motor response after a PD drug intake and increased severity of e.g. bradykinesia, rigidity, and resting tremor. The term comprises the so-called predictable end-of-dose motor fluctuations characterised by end-of-dose failure of the symptom control. End-of-dose wearing off symptoms may also include fluctuating non motor symptoms, such as anxiety and pain. Motor complications may also include rapid and unpredictable swings from mobility to immobility ("on-off" phenomenon).

The terms "repeated dose" and "in a repeated manner" refer to multiple administration of a drug during the day, usually from at least 3 up to 10 times a day, depending on the severity of the disease of a patient with Parkinson's disease and on the subsequent need of levodopa.

The term "oral solid dosage form" refers to a single unit or multiunit solid oral dosage form. A single unit oral dosage form may be a combination formulation, such as a tablet, which comprises two or more of the drug substances. In one embodiment the single unit oral dosage form is a combination formulation, such as a tablet or a capsule, which comprises all of the drug substances. A multi-unit solid oral dosage form may be a dosage form comprising a plurality of oral solid units in the form of small particles (for instance, a capsule or sachet filled with minitablets, granules or pellets) which, when taken simultaneously or sequentially, provide a unit dose. The terms "multiple-unit" or "multi-particulate" oral dosage form may also be used to refer to such a multi-unit solid oral dosage form. The particles may be also be used as such in a so-called sprinkle form that can be sprinkled directly onto food or liquids for easy ingestion. Multiple-unit dosage forms have been accepted to provide advantages over single-unit dosage forms. The pharmacokinetics of the drug release from a multiple-unit dosage form is more uniform than from the single-unit dosage form, because the

pharmacokinetics of the drug release from a multiple-unit dosage form is the average value of the kinetics of the drug release from individual subunits. The units of a multiple-unit dosage form may scatter freely in the gastrointestinal tract and act like liquids leaving the stomach within a short period of time, which results in improved biopharmaceutical characteristics, such as improved bioavailability, reduced food effect on plasma profiles and, ultimately, reduced variability of plasma profiles and a lower possibility of local irritation in the gastrointestinal tract.

The term "minitablet" refers to a compressed pharmaceutical formulation that has dimensions of length and breadth (or, depending on its shape, a diameter) each equal to or less than 5 mm.

The term "granule" refers to a pharmaceutical formulation in which the ingredients have been mixed together in order to intimately and evenly disperse the drug substance(s) within some or all of the other ingredients and to increase the particle size. Suitable techniques are known in the pharmaceutical industry and can be selected from wet granulation, melt granulation or dry granulation.

The term "pellet" refers to a substantially spherical solid particle, the diameter of which may range from about 100 microns to about 3 mm, which has been made by layering onto a particle (for instance, on a non-pareil) or by extrusion optionally followed by spheronisation or other similar known techniques. Generally pellets are more spherical in appearance than minitablets. The term "immediate release (IR) dosage form" refers to a pharmaceutical dosage form which releases the active ingredient immediately upon administration and will result in 80 - 100 %, preferably 90 - 100 %, dissolution of the dose amount within one hour. For 4,5- dihydroxy-2-(4-methylbenzyl)isophthalonitrile, the dissolution method is USP apparatus II (paddles): 75 rpm; medium: 0.05 M sodium acetate pH 5.5, 900 ml. For carbidopa, the dissolution method is USP apparatus II (paddles): 75 rpm; medium: 0.02 M hydrochloric acid and sodium chloride pH 1.6, 750 ml.

The term“immediate release or slightly modified release (IR or slightly MR) dosage form” refers to a pharmaceutical dosage form which releases the active ingredient upon

administration and will result in not less than 20 %, preferably not less than 30 %, in 30 min; not less than 50 %, preferably not less than 60 %, in 60 min; and not less than 80 % in 120 min. For levodopa, dissolution conditions are the same as for carbidopa (see above).

The term "solvent" refers to solid non-covalent combinations of a solvent and a solute. The solvent can be an organic solvent or water. When the solvent is water, the solvate can also be referred to as hydrate. Thus, the term "hydrate" refers to solid non-covalent combinations of water and a solute.

EXAMPLES

Example 1

The objective of the study was to evaluate the dose effects of 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile and carbidopa on levodopa plasma PK at 3 modified release levodopa strengths (50, 100 and 150 mg). In addition, the plasma PK of levodopa after administration of modified release levodopa in combination with carbidopa and 4,5- dihydroxy-2-(4-methylbenzyl)isophthalonitrile was compared to the standard

levodopa/carbidopa (Sinemet®) at levodopa dose level 100 mg. All treatments were administered orally.

An open, randomised, repeated dose PK study was conducted with 56 healthy male subjects. The study consisted of 4 parallel groups (14 subjects per group) with 4-treatment crossover design. The effect of three standard carbidopa (1 :4 carbidopa to levodopa ratio, 12.5, 25 and 37.5 mg) doses, 65 mg carbidopa dose and two 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile (50 and 100 mg) doses on MR levodopa (50, 100 and 150 mg) PK was investigated. Carbidopa and 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile (if included in the treatment period) were administered q.i.d for 7 days and on the 7^th day levodopa was added into the treatment. There was a wash-out for at least 4 days between the treatment periods.

On the 7^th day of treatment (levodopa administration day), peripheral venous blood samples were drawn frequently for determination of levodopa, carbidopa, the levodopa metabolite 3- O-methyldopa and 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile concentration in plasma. The concentrations were determined with validated LC-MS/MS method.

The primary PK variable for the evaluation of levodopa PK was AUCo-24_h to describe the total levodopa plasma exposure. The secondary PK variable was C_min,taU to describe minimum plasma concentrations of levodopa during the dosing intervals. The PK variables were analysed using a mixed linear model with a 90 % confidence interval (Cl) applicable for the crossover design. The statistical model included treatment and period as fixed effects and subject as a random effect.

56 healthy male subjects were randomised and entered into the study. 55 subjects were dosed with levodopa. Majority of the subjects were Caucasian. Mean (SD) age was 46.4 (12.2) years, weight 78.7 (9.6) kg, height 176.7 (7.0) cm and body mass index (BMI) 25.2 (2.4) kg/m². 50 of the randomised subjects completed the study. Statistical analyses for PK parameters were performed using subjects without major protocol violations (n = 48).

Results

At each levodopa dose level, 65 mg of carbidopa significantly increased the exposure (AUC_0- 24_h) of modified release levodopa when compared to standard carbidopa (1 :4 carbidopa to levodopa ratio) dose. Addition of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile (50 or 100 mg) into the treatment dose dependently, significantly further increased the AUC_0-24_h and also the minimum plasma concentrations of levodopa without significantly increasing

the maximum plasma concentrations of levodopa. Consequently, addition of 50 mg

of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile significantly decreased the fluctuation in levodopa plasma concentrations. 100 mg of 4,5-dihydroxy-2-(4-

methylbenzyl)isophthalonitrile further decreased the fluctuation in

levodopa plasma concentrations.

When compared to Sinemet®

100 mg + carbidopa 65 mg + MR levodopa 100 mg treatment increased levodopa A

by

and consequently decreased levodopa fluctuation

The results are summarised in table 1.

¹ Estimates are received from an RM-ANOVA model, where dosing intervals are used as within subject term. Example 2

The objective of the study was to evaluate the plasma pharmacokinetics (PK) of orally administered modified release levodopa in combination with carbidopa and 4,5-dihydroxy-2- (4-methylbenzyl)isophthalonitrile compared to the standard levodopa/carbidopa/entacapone (Stalevo®) containing 100 mg of levodopa.

An open, randomised, 3 -period crossover PK study was conducted with 15 healthy subjects (treatment of the invention). 100 mg of COMT inhibitor (IR) and 65 mg of carbidopa (IR) were administered q.i.d every 3.5 hours for 6 days and on the 7^th day 100 mg of levodopa (MR) q.i.d. was added to the treatment. There was a wash-out for at least 4 days between the treatment periods.

100 mg of 4, 5-dihydro xy-2-(4-methylbenzyl)isophthalonitrile and 65 mg of carbidopa and 100 mg of levodopa were compared to Stalevo®. On the 7^th day of treatment (levodopa administration day), peripheral venous blood samples were drawn frequently for determination of levodopa, carbidopa, the levodopa metabolite 3- O-methyldopa and 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile concentration in plasma. The concentrations were determined with validated LC-MS/MS method.

The primary PK variable for the evaluation of levodopa PK was peak-through fluctuation for each dosing interval (PTF_tau). The secondary PK variables were and

variables were analysed using a mixed linear model with a 90 % Cl applicable for the crossover design. The statistical model included treatment, treatment sequence, dosing interval and period as fixed effects and subject by period interaction as a random effect. The results were covariate adjusted for age, weight and gender. 15 healthy subjects were randomised and entered into the study. All subjects were Caucasian;

9 of them were females and 6 were males. Mean (SD) age was 28.1 (8.0) years, weight 70.3 (11.6) kg, height 174.5 (8.3) cm and BMI 22.9 (1.9) kg/m². 12 of the randomised subjects completed the study according to the protocol.

Results

The fluctuations of levodopa plasma concentrations, i.e. levodopa peak-through fluctuation for each dosing interval decreased by more than 30 %, C_min,tau was

increased by 36 % and AUC₀-24h was increased by 15 % compared to Stalevo®, with a trend towards reduced

The results are summarised in table 2. Table 2. Statistical analysis of levodopa PK parameters after multiple doses of study treatments (q.i.d. 3.5 h apart).

weight and gender as covariates

1 Estimates are received from an RM-ANOVA model, where dosing intervals are used as within subject term.

Example 3

In PD patients with COMT^HH and COMT^HL, increasing the dose of carbidopa to 65 mg in combination with the COMT inhibitor 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile in an amount of 100 mg increases the efficacy of levodopa (75, 100, 125 and 150 mg) treatment (“invention”) by reducing OFF-time significantly in comparison to standard Stalevo®

(75/18.75/200 mg, 100/25/200 mg, 125/31.25/200 mg and 150/37.5/200 mg levodopa, carbidopa and entacapone). In the cross-over study, the first randomized treatment (either the“invention” or standard) was administered for 4 weeks and then switched to the other treatment for another 4 weeks. Depending on each patient’s individual needs to control Parkinson’s disease symptoms, from 4 to 8 daily doses of the treatments were administered and the dosing frequency was kept the same during both of the 4 week treatment periods.

The reduction of OFF-time was evident in the patients having at least one allele of the fast COMT gene COMT^HL or COMT^HH but not in patients with both alleles of low activity COMT^LL. The results are presented in table 3.

Table 3. OFF-time reduction from baseline by COMT enzyme RS4680 genotype

Example 4 The levodopa pellets according to the invention are described in table 4 and the granules made of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile and carbidopa in table 5.

Table 4. Levodopa pellets

Pellet ingredients are mixed in a high shear mixer. Purified water is added after which the formed wet mass is extruded in twin-screw or basket type extruder. The extrudate is charged and spheronised in a spheronizer. The spheres obtained from the spheronizer are dried in fluid bed dryer or on trays. Finally, the pellets are screened. The screened pellets may be lubricated with talc. Table 5. Granules made of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile and carbidopa

^{1 1} The amounts of active ingredients are expressed as anhydrate form. The active ingredients are weighed as hydrates.

Granule components are mixed in a high shear mixer. Granulation liquid is sprayed in the powder blend. The binder (polyvinylpyrrolidone) may be dissolved in purified water, added as a powder or a combination thereof. After addition of granulation liquid, the granules are dried in a fluid bed dryer and screened with a conical mill. The granules may be lubricated by adding extragranular magnesium stearate.

Granules and pellets are encapsulated, compressed into tablets or filled into sachets.

Example 5

Granule components are mixed in a fluid bed granulator. Granulation liquid is sprayed in the powder blend. After liquid addition, the granules are dried in a fluid bed granulator. After sieving, the granules are lubricated. Fast dissolution rate is achieved with compositions 1 and 2. Porous granules are achieved with compositions 3 and 4.

Example 6

Granule components are mixed in a high shear mixer. Granulation liquid is sprayed in the powder blend. After liquid addition, the granules are dried in a fluid bed granulator. After sieving, the granules are lubricated. Larger granules are achieved with composition 5. Granules with good flowability are achieved with composition 6. Granules with superior compactibility are achieved with composition 7.

Example 7

Granule components are fed into a continuous mixer. Powder blend is granulated with granulation liquid in a twin-screw granulator. The granules are dried in a fluid bed. After sieving, the granules are lubricated. Granules with bimodal particle size distribution are achieved. Granules with good compactibility are achieved with composition 10. Porous granules are achieved with compositions 11 and 12.

Example 8

Materials excluding magnesium stearate are mixed in a tumbling mixer. Magnesium stearate is added and the mixture is encapsulated. Fast dissolution is achieved. Example 9

Pellet components are mixed in a high shear mixer. Optional binder or release modifying agent is added dissolved in purified water, as a powder or a combination thereof

(compositions 19 and 20). After liquid addition, the formed wet mass is extruded in twin- screw or basket type extruder. The extrudate is charged and spheronised in a spheronizer. The spheres obtained from the spheronizer are dried in fluid bed dryer or on trays. Finally, blend is screened and the pellets retained on 0.5-mm screen are collected. Optionally, the final blend is prepared by blending the screened pellets with talc or colloidal silica. Pellets are hard and round with slightly modified or immediate release.

Example 10

Micronised levodopa is dispersed in a water solution of polyvinylpyrrolidone or other binder and then colloidal silica is added. Levodopa suspension is layered on top of sugar

(composition 22) or microcrystalline cellulose (composition 23) beads of size 100-1,500 pm. Layering is performed in fluid bed coater. Pellets are hard and round with immediate release.

Example 11

Pellets are manufactured with extrusion spheronisation or fluid bed layering and coated in fluid bed coater (Wurster or FlexStream) for modifying the release. Coating thickness is 4-15 % (weight gain). Coating liquid is aqueous or organic. Pellets are hard and round with slightly modified or modified release.

Example 12

Granule components are mixed in a high shear mixer. Granulation liquid is sprayed in the powder blend. Binder is added dissolved in purified water, as a powder or a combination thereof. After liquid addition, the granules are dried in a fluid bed dryer or on trays. After sieving, the granules are lubricated. With compositions 31, 32 and 33, release is modified, slightly modified and immediate, respectively.

Example 13

Levodopa, croscarmellose sodium, lactose monohydrate, microcrystalline cellulose, crospovidone and optionally hypromellose or hydroxyethylcellulose and optionally sodium lauryl sulphate are mixed in a suitable blender or the ingredients are fed to a ring layer granulator with multiple gravimetric feeders. Then granulation liquid (purified water or purified water with crospovidone and optionally sodium lauryl sulphate) is added to the ring layer granulator. The wet mass is fed to a radial extruder for extrusion. The extrudates are conveyed to a spheronizer. The spheronized pellets are dried in a fluid bed dryer. After drying, optionally talc is added onto the dry pellets with subsequent mixing in the fluid bed.

Example 14

Levodopa, croscarmellose sodium, lactose monohydrate, microcrystalline cellulose and crospovidone or gelatin and optionally sodium lauryl sulphate are mixed in a high shear mixer. Then granulation liquid (purified water or purified water with sodium lauryl sulphate and crospovidone or gelatin) is sprayed in the mixed powder blend. A predetermined amount of granulation liquid is used, after which a wet massing phase is possibly needed. The wet granules are dried and optionally sieved. Sodium stearyl fumarate or magnesium stearate is added and mixed with the granules. The dried granules are compressed into minitablets. Optionally talc is added. Minitablets are up to 4 mm in diameter and can be encapsulated in hard gelatin or hypromellose capsule shells.

Example 15

The aforementioned granules, pellets and optionally talc are encapsulated in hard gelatin or hypromellose capsule shells.

Example 16 The aforementioned granules, pellets and optionally filler, disintegrant and/or lubricant are blended and then compressed into tablets. The tablets might be coated.

Example 17

The aforementioned granules, pellets and optionally lubricant are blended and then filled into sachets.

Example 18

Acetonitrile (56 ml), aluminium chloride (8 g) and sodium iodide (9.5 g) are charged. 4- hydroxy-5-methoxy-2-(4-methylbenzyl)isophthalonitrile (10 g) is added. The mixture is heated to 45 °C, stirred for 4 h and cooled to 15 °C. Water (60 ml) and 30 % HC1 (15 ml) are added slowly at 15 °C. Sodium sulphite (2 g) is added and the mixture is stirred for 90 min at 22 °C. The phases are allowed to settle and the aqueous phase is separated off. Water (30 ml), sodium chloride (3 g), sodium sulphite (1 g) and 30 % HC1 (1.5 ml) are added. The mixture is stirred for 1 h at 22 °C and the phases are allowed to settle. The aqueous phase is separated off. Solvents are distilled off under atmospheric pressure until the volume of the residue is 20 ml. Ethanol (80 ml) is added and the distillation is continued until the volume of the residue is 30 ml. The residue is cooled to 70 °C and ethanol (16 ml) and water (65 ml) are added. The mixture is cooled to 0 °C in 9 h and stirred for at least 1 h at 0 °C. The crystalline product is filtered and washed with water (15 ml). The product is dried under reduced pressure at 35-40 °C in an agitated dryer. Crystalline form II of 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile monohydrate is obtained. The yield is 92.5 % and the high- performance liquid chromatography purity 99.5 %. X-ray powder diffraction pattern are obtained on a PANalytical X’Celerator Q-Q diffractometer with CuKa radiation (40 kV, 30 mA). The diffractometer is operated in reflection mode. The measurements are performed in the range of 3°-40° 20. 100-300 mg of the powder is placed in the sample holder and the surface is pressed. The X-ray powder diffractogram of crystalline form II of 4,5-dihydroxy-2- (4-methylbenzyl)isophthalonitrile monohydrate is shown in Figure 1.

Claims

1. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use in a method for the treatment of Parkinson's disease by a simultaneous or sequential administration to a patient of

(ii) carbidopa in an amount ranging from 65 to 105 mg, and

(iii) levodopa in an amount ranging from 50 to 200 mg.

2. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to claim 1, wherein the patient is a COMT^HH or a COMT^HL patient.

3. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to claim 1 or 2, wherein the patient is a wearing off patient and the three active ingredients are administered to the PD patient in a repeated manner.

4. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to any of claims 1 to 3, wherein carbidopa is present in an amount of 65 mg.

5. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to any of claims 1 to 4, wherein 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is present in an amount of 100 mg.

6. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to any of claims 1 to 5, wherein 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate having at least peaks at 20 of about 6.1° and 11.2° in an X-ray powder diffractogram.

7. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to any of claims 1 to 5, wherein 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate having at least peaks at 20 of about 6.1° and 14.7° in an X-ray powder diffractogram.

8. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to claim 6 or 7, wherein 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate having at least peaks at 20 of about 6.1°, 11.2°, 14.7°, 16.2°, 21.8°, 24.0°, 26.2° and 26.9° in an X- ray powder diffractogram.

9. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to any of claims 6 to 8, wherein 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate characterized by an X-ray powder diffractogram substantially as illustrated in Figure 1.

10. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to any of claims 6 to 9, wherein 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate containing less than 25 % by weight of other 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile solvates and crystalline forms thereof.

11. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to claim 10, wherein 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate containing less than 10 % by weight of other 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile solvates and crystalline forms thereof.

12. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to claim 11, wherein 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate containing less than 6 % by weight of other 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile solvates and crystalline forms thereof.

13. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to claim 12, wherein 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile monohydrate containing less than 4 % by weight of other 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile solvates and crystalline forms thereof.

14. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to any of claims 1 to 13, wherein levodopa is present in an amount of 50 mg, 100 mg, 150 mg or 200 mg.

15. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to any of claims 1 to 14, wherein said treatment comprises administering an oral solid dosage form.

16. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to claim 15, wherein the oral dosage form is a combination dosage form.

17. 4,5-Dihydroxy-2-(4-methylbenzyl)isophthalonitrile, carbidopa and levodopa for use according to claim 15 or 16, wherein the oral dosage form is a capsule.

18. An oral dosage form comprising

(ii) carbidopa in an amount ranging from 65 to 105 mg, and

(iii) levodopa in an amount ranging from 50 to 200 mg.

19. The oral dosage form according to claim 18, wherein carbidopa is present in an amount of 65 mg.

20. The oral dosage form according to claim 18 or 19, wherein 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile is present in an amount of 100 mg.

21. The oral dosage form according to any of claims 18 or 20, wherein 4,5-dihydroxy-2- (4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile monohydrate having at least peaks at 20 of about 6.1° and

11.2° in an X-ray powder diffractogram.

22. The oral dosage form according to any of claims 18 or 20, wherein 4,5-dihydroxy-2- (4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile monohydrate having at least peaks at 20 of about 6.1° and 14.7° in an X-ray powder diffractogram.

23. The oral dosage form according to claim 21 or 22, wherein 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile monohydrate having at least peaks at 20 of about 6.1°, 11.2°, 14.7°, 16.2°, 21.8°, 24.0°, 26.2° and 26.9° in an X-ray powder diffractogram.

24. The oral dosage form according to any of claims 21 to 23, wherein 4,5-dihydroxy-2- (4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile monohydrate characterized by an X-ray powder diffractogram substantially as illustrated in Figure 1.

25. The oral dosage form according to any of claims 21 to 24, wherein 4,5-dihydroxy-2- (4-methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile monohydrate containing less than 25 % by weight of other 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile solvates and crystalline forms thereof.

26. The oral dosage form according to claim 25, wherein 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile monohydrate containing less than 10 % by weight of other 4,5-dihydroxy-2-(4-methylbenzyl)isophthalonitrile solvates and crystalline forms thereof.

27. The oral dosage form according to claim 26, wherein 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile monohydrate containing less than 6 % by weight of other 4,5- dihydroxy-2-(4-methylbenzyl)isophthalonitrile solvates and crystalline forms thereof.

28. The oral dosage form according to claim 27, wherein 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile is crystalline form II of 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile monohydrate containing less than 4 % by weight of other 4,5- dihydroxy-2-(4-methylbenzyl)isophthalonitrile solvates and crystalline forms thereof.

29. The oral dosage form according to any of claims 18 to 28, wherein levodopa is present in an amount of 50 mg, 100 mg, 150 mg or 200 mg.

30. The oral dosage form according to any of claims 9 to 29, wherein the oral dosage form is a combination dosage form.

31. The oral dosage form according to any of claims 9 to 30, wherein the oral dosage form is a capsule or a tablet.

32. The oral dosage form according to any of claims 9 to 31 , wherein 4,5-dihydroxy-2- (4-methylbenzyl)isophthalonitrile and carbidopa are in the same granules.

33. The oral dosage form according to any of claims 9 to 32, wherein the dosage form is an immediate release dosage form with regard to 4,5-dihydroxy-2-(4- methylbenzyl)isophthalonitrile and carbidopa.

34. The oral dosage form according to any of claims 9 to 33, wherein levodopa is in a pellet.

35. The oral dosage form according to claim 34, wherein the pellet is coated.

36. The oral dosage form according to claim 34, wherein the pellet is uncoated.

37. The oral dosage form according to any of claims 9 to 33, wherein levodopa is in a granule.

38. The oral dosage form according to any of claims 9 to 37, wherein the dosage form is immediate release or slightly modified release dosage form with regard to levodopa.

39. The dosage form according to claim 32, wherein the total drug load of 4,5-dihydroxy- 2-(4-methylbenzyl)isophthalonitrile and carbidopa in the granules is from 60 to 95 w/w %.

40. The dosage form according to claim 39, wherein the total drug load of 4,5-dihydroxy- 2-(4-methylbenzyl)isophthalonitrile and carbidopa in the granules is from 70 to 85 w/w %.

41. The dosage form according to claim 40, wherein the total drug load of 4,5-dihydroxy-

2-(4-methylbenzyl)isophthalonitrile and carbidopa in the granules is from 80 to 85 w/w %.

42. The dosage form according to claim 34, wherein the drug load of levodopa in the pellet is from 60 to 90 w/w %.

43. The dosage form according to claim 42, wherein the drug load of levodopa in the pellet is from 70 to 80 w/w %.

44. The dosage form according to claim 43, wherein the drug load of levodopa in the pellet is from 70 to 75 w/w %.