WO2017014599A1 - Composition for stabilizing radiochemical purity of [18f]fluoro-dopa and method for preparing same - Google Patents

Abstract

The present invention relates to a composition for stabilizing the radiochemical purity of [¹⁸F]fluoro-dopa by inhibiting the formation of impurities during a predetermined time period, and a method for preparing the same. The composition according to the present invention comprises: [¹⁸F]fluoro-dopa; ethanol at a concentration of 5% to 30%(v/v) relative to the total composition; and a buffer having a pKa value of 6 to 8.1 at 25°C, wherein the composition stabilizes the radiochemical purity of [¹⁸F]fluoro-dopa by inhibiting the formation of impurities during a predetermined time period.

Description

Compositions for stabilizing radiochemical purity of [18 F] fluoro-waveguides and methods for preparing the same

The present invention is ^[18 F] fluoro-as for the method for producing the composition and its stabilizing the radiochemical purity of the waveguide, and more particularly, to a ^[18 F] fluoro By inhibiting for a predetermined time, impurity generation-guided radiation of the chemical It relates to a composition for stabilizing purity and a method for preparing the same.

Recent brain diseases such as Parkinson's disease, depression, schizophrenia and Alzheimer's disease; Heart disease due to stress and dietary changes; In order to diagnose various diseases such as cancer caused by exposure to various harmful substances in the human body, various imaging methods are used, and Positron Emission Tomography (PET) It is used. Positron emission tomography is a method of imaging the distribution and biochemical changes of radiopharmaceuticals in vivo by intravenous injection of an organic compound labeled with a radioisotope that emits positrons in vivo. Therefore, positron emission tomography can quantitatively measure the biochemical changes of living organisms at the site of lesions, thereby measuring disease development and predicting the extent of treatment (A. Agool, RH Slart, KK Thorp, AW Glaudemans, DC Cobben, LB Been, FR Burlage, PH Elsinga, RA Dierckx, E. Vellenga, JL Holter, Nucl.Med.Commun. 2011 , 32, 14 .; N. Aide, K. Kinross, C. Cullinane, P. Roselt , K. Waldeck.O, Neels, D. Dorow, G. McArthur, RJ Hicks, J. Nucl.Med. 2011 , 51, 1559 .; A. Debucquoy, E. Devos, P. Vermaelen, W. Landuyt, S De Weer, F. Van Den Heuvel, K. Haustermans, Int. J. Radiat. Biol. 2009 , 85, 763.).

Radioactive isotopes used for positron emission tomography include fluoride ([ ¹⁸ F] F), carbon ([ ¹⁵ C] C), nitrogen ([ ¹³ N] N), oxygen ([ ¹⁵ O] O) and gallium ([ ⁶⁸ Ga] Ga), among which [ ¹⁸ F] fluoride has a size similar to that of hydrogen, forms a stable bond with carbon of an organic compound, is easy to produce, and has an appropriate half-life (110 minutes). It is reported to be very suitable for performing positron emission tomography (Lasne, MC; Perrio, C .; Rouden, J .; Barre, L .; Roeda, D .; Dolle, F .; Crouzel, C). Contrast Agents II, Topics in Current Chemistry, Springer-Verlag, Berlin, 2002 , 222, 201-258 .; Bolton, RJ Labelled Compd. Radiopharm. 2002 , 45, 485-528). [ ¹⁸ F] fluorides are generally prepared by investigating protons in [ ¹⁸ O] H 2 O using cyclotron, a circular accelerator (MR Kilbourn, JT Hood, MJ Welch, Int. J. Appl. Radiat. Isot. 1984 , 35, 599 .; GK Mulholland, RD Hichwa, MR Kilbourn, J. Moskwa, J. Label.Compd. Radiopharm. 1989 , 26, 140.).

Positron emission tomography photographing radiopharmaceutical of ^[18 F] fluoro-waveguide ^{(18 F-FLUORODOPA, [18} F] FLUORODOPA, 18 F-6-L-FLUORODOPA, [18 F] -FLUORO-L-DOPA, L-6 PET or PET / CT imaging with [ ¹⁸ F] FLUORO-3,4-DIHYDROXYPHENYLALANINE (FDOPA) is used to measure the loss of dopamine nerve endings in the brain striatum. It can be used to differentiate between vocal progression and Parkinson's syndrome (Fischman, A. Radiol. Clin. N. Am. 2005 , 43, 93-106; Vingerhoets, FJ; Schulzer, M .; Ruth, TJ; Holden, JE; Snow , BJJ Nucl.Med. 1996 , 37, 421-426 .; Sawle, GW; Wroe, SJ; Lees, AJ; Brooks, DJ; Frackowiak, RS; Ann. Neurol. 1992 , 32, 609-617). In addition, it is possible to measure the pathophysiological function of tissues or organs with increased intracellular migration and decarboxylation of the amino acid dihydroxyphenylalanine, which is used for diagnosis and location of insulin species with hyperinsulinemia in infants and children. (Tessonnier, L .; Sebag, F .; Ghander, C .; De Micco, C .; Reynaud, R .; Palazzo, FF; Conte-Devolx, B .; Henny, JF; Mundler, O .; Taieb, DJ Clin.Endocrinol Metab. 2010 , 95, 303-307; Ribeiro, MJ; De Lonlay, P .; Delzescaux, T .; Boddaert, N .; Jaubert, F .; Bourgeois, S .; Dolle, F; Nihoul- Fekete, C .; Syrota, A .; Brunelle, FJ Nucl.Med. 2005 , 46, 560-566).

FDOPA is fluorinated L-DOPA and the bioclassification of FDOPA is similar to the normal classification of L-DOPA (http://interactive.snm.org/docs/PET_PROS/FDOPA.pdf).

L-DOPA, on the other hand, is known to be unstable in aqueous alkaline solutions and well oxidized by oxygen (https://www.sigmaaldrich.com/content/dam/sigmaaldrich/docs/Sigma/Product_Information_Sheet/d9628pis.pdf). The temperature is known as 2-8 ° C. (http://www.sigmaaldrich.com/catalog/product/aldrich/333786lang=en&region=US). Due to these chemical properties of L-DOPA, the [ ¹⁸ F] fluoro-dopa reported to date is also difficult to store and use. [ ¹⁸ F] fluoro-dopa is stable in acidic conditions and unstable in neutral conditions. It is known to be used in the acidic state and neutralized just before use. In the US Pharmacopoeia (USP) and the European Pharmacopeia (EP), the pH is set at 4.0 to 5.5 (USP31 / NF26, vol 2. 2008. 2193-2194 .; EP 6.0, 2008. 990-992 ,; Kao, CH; Hsu, WL; Xie, HL; Lin, MC; Lan, WC; Chao, HY; Ann Nucl Med. 2011 , 25, 309-316). When the pH is 2.3-3.0, it is a strong acid adult condition. In addition, referring to the IASOdopa SPC (summary of product characteristics, http://agence-prd.ansm.sante.fr/html/par_eu/20080604_fr328_iasodopa_spc.pdf), it must be stored at 2 to 8 ° C after pH neutralization, and after neutralization 2 It is stated to be used within hours and above pH 4.5 it is described that [ ¹⁸ F] fluoro-dopa is oxidized. Accordingly, due to the half-life of radioisotopes ( ¹⁸ F, 110 minutes), radiopharmaceuticals should be manufactured and used whenever necessary, and the radioactive content of radiopharmaceuticals may vary due to the difference in the amount and yield of starting radioactivity. And the volume of radiopharmaceutical administered to the patient over time due to the half-life nature after manufacture. In addition, since [ ¹⁸ F] fluoro-dopa is stored at acidic pH, it must be neutralized for administration in the human body, and there is a risk of causing metabolic acidosis if injected into a patient in a strong acid state without neutralization. .

Thus, to the PET diagnosis ^[18 F] fluoro-when using a wave guide, by ^[18 F] fluoro being stored in time limit, the acidic state according to the half-life of the radioisotope-neutralized necessarily to administration of the waveguide to the human body There are a lot of inconveniences due to the necessary constraints, the use time constraints that must be administered to the human body within 2 hours after neutralization, and the constraints that must be refrigerated.

Prior art documents related to the present invention include Korean Patent Application No. 10-2007-7020237 (name of the invention: a new pharmaceutical composition useful for treating Parkinson's disease, filed on Sep. 04, 2007).

In order to solve the above problems, ^[18 F] fluoro-a ^[18 F] fluoro after synthesis of the waveguide 2 to during 6 hours even with the available radiochemical purity as radiopharmaceuticals-composition to stabilize the radiochemical purity of the waveguide It is intended to provide a method of preparation thereof.

Additionally, ^[18 F] fluoro-after synthesis of the waveguide 2 to 6 hours without having the oxidation occurs at neutral pH, preferably pH 6 ~ 8 non-acidic pH with free radiochemical purity as radiopharmaceuticals ^[18 while F] to provide a composition for stabilizing the radiochemical purity of fluoro-dopa and a method for preparing the same.

In addition, the present invention provides a composition for stabilizing the radiochemical purity of [ ¹⁸ F] fluoro-dopa that does not require refrigeration and has a radiochemical purity that can be used as a radiopharmaceutical even at room temperature.

In order to achieve the above object, according to the present invention, [ ¹⁸ F] fluoro-dopa; Ethanol at a concentration of 5% to 30% (V / V) relative to the total composition; There is provided a composition comprising a buffer having a value of pKa 6 to 8.1 at 25 ° C. to stabilize the radiochemical purity of the [ ¹⁸ F] fluoro-waveguide by inhibiting the generation of impurities for a predetermined time.

The composition is a composition which exhibits at least 90% radiochemical purity by inhibiting the generation of impurities for 2-6 hours after the synthesis of the [ ¹⁸ F] fluoro-dopa at pH 6-8.

The composition is a composition that exhibits at least 90% of radiochemical purity by inhibiting the generation of impurities for 2 to 6 hours after the synthesis of the [ ¹⁸ F] fluoro-dopa at room temperature.

 The buffer having a value of pKa 6.1 to 8.1 at 25 ° C is PBS (PHOSPHATE BUFFERED SALINE), Citrate Buffer (CITRATE BUFFER), MES (2- (NMORPHOLINO) ETHANESULFONIC ACID), BIS-TRIS (2,2-BIS (HYDROXYMETHYL) -2,2 ', 2' '-NITRILOTRIETHANOL) Buffer, MOPSO (3-MORPHOLINO-2-HYDROXYPROPANESULFONIC ACID) Buffer, HEPES (4- (20HYDROXETHYL) -1-PIPERAZINEETHANSFULFONIC ACID) Buffer, and TRIS (TRIS (HYDROXYMET) ) AMINOMETHANE) at least one selected from the group consisting of buffers.

The dopa includes levodopa (L-dopa), carbadopa, dopamine or derivatives thereof.

In a composition for stabilizing the radiochemical purity of the [ ¹⁸ F] fluoro-dopa according to the present invention, the [ ¹⁸ F] fluoro-dopa is included at a radioactive concentration of 37 to 37,000 MBq / ml and the ethanol and the buffer The total volume of 100% (V / V) of the total composition is included. For example, if the ethanol is included at a concentration of 5% to 30% (V / V) of the total composition, the buffer is 70% of the total composition. % To 95%, so that the sum of the buffer concentration and the concentration of ethanol can be 100% (V / V).

Furthermore, in order to achieve the above object, according to the present invention, [ ¹⁸ F] fluoro-dopa; In case the total composition from about 5% to about 30% (V / V) of ethanol and 25 ℃ of concentrations, including the steps of mixing the buffer with a value of pKa 6 to 8.1, inhibit impurities generated for a predetermined period of time the ^[18 F] A method of preparing a composition for stabilizing the radiochemical purity of fluoro-dopa is provided.

The composition inhibits the generation of impurities for 2-6 hours after the synthesis of the [ ¹⁸ F] fluoro-dopa at pH 6-8, resulting in at least 90% radiochemical purity.

The composition inhibits the generation of impurities for 2-6 hours after the synthesis of the [ ¹⁸ F] fluoro-dopa at room temperature to exhibit at least 90% radiochemical purity.

The buffer having a value of pKa 6.1 to 8.1 at 25 ° C is PBS (PHOSPHATE BUFFERED SALINE), Citrate Buffer (CITRATE BUFFER), MES (2- (NMORPHOLINO) ETHANESULFONIC ACID), BIS-TRIS (2,2-BIS (HYDROXYMETHYL) -2,2 ', 2' '-NITRILOTRIETHANOL) Buffer, MOPSO (3-MORPHOLINO-2-HYDROXYPROPANESULFONIC ACID) Buffer, HEPES (4- (20HYDROXETHYL) -1-PIPERAZINEETHANSFULFONIC ACID) Buffer, and TRIS (TRIS (HYDROXYMET) ) AMINOMETHANE) at least one selected from the group consisting of buffers.

The dopa comprises levodopa (L-dopa), carbadopa, dopamine or derivatives thereof.

According to the invention, ^[18 F] fluoro-composition and its stabilizing the radiochemical purity of the waveguide - in ^[18 F] fluoro after synthesis of the waveguide 2 to during 6 hours even with the available radiochemical purity as a radiopharmaceutical A manufacturing method is provided.

Additionally, ^[18 F] fluoro-after synthesis of the waveguide 2 to 6 hours without having the oxidation occurs at neutral pH, preferably pH 6 ~ 8 non-acidic pH with free radiochemical purity as radiopharmaceuticals ^[18 while F] Provided are compositions for stabilizing the radiochemical purity of fluoro-waveguides and methods for their preparation.

There is also provided a composition for stabilizing the radiochemical purity of [ ¹⁸ F] fluoro-dopa that does not require refrigeration and has a radiochemical purity that can be used as a radiopharmaceutical even at room temperature.

1 is an HPLC chromatogram of ethanol-free [ ¹⁸ F] fluoro-dopa formulation showing impurity formation 2 hours after neutralization;

FIG. 2 is an HPLC chromatogram of ethanol-free [ ¹⁸ F] fluoro-dopa formulation showing impurity formation 6 hours after neutralization;

FIG. 3 is a graph showing the radiochemical purity of ethanol free and added [ ¹⁸ F] fluoro-dopa formulations over time after neutralization to pH 6;

FIG. 4 is a graph showing the radiochemical purity of ethanol free and added [ ¹⁸ F] fluoro-dopa formulations over time after neutralization to pH 7.

FIG. 5 is a graph showing the radiochemical purity of ethanol free and added [ ¹⁸ F] fluoro-dopa formulations over time after neutralization to pH 8;

FIG. 6 is a TLC chromatogram of [ ¹⁸ F] fluoro-dopa formulation with 10% ethanol showing impurity formation 1 hour after neutralization;

FIG. 7 is a graph showing the radiochemical purity of ethanol free and added [ ¹⁸ F] fluoro-dopa formulations, depending on the storage temperature after neutralization.

FIG. 8 is a PET image of ethanol addition buffer without addition [ ¹⁸ F] fluoro-dopa formulation over time after neutralization; FIG.

FIG. 9 is a graph depicting the radiochemical purity of ethanol and buffer addition [ ¹⁸ F] fluoro-dopa formulations over time after neutralization.

Hereinafter, the present invention will be described in detail so that those skilled in the art can easily implement the present invention. The invention may be embodied in many different forms and should not be construed as limited to the experimental examples set forth herein. In order to clearly describe the present invention, parts irrelevant to the description are omitted, and like reference numerals designate like elements throughout the specification.

The present invention is directed to [ ¹⁸ F] fluoro-dopa; Ethanol at a concentration of 5% to 30% (V / V) relative to the total composition; Provided is a composition comprising a buffer having a value of pKa 6 to 8.1 at 25 ° C. to inhibit impurity production for a predetermined time to stabilize the radiochemical purity of the [ ¹⁸ F] fluoro-waveguide.

[ ¹⁸ F] fluoro-dopa is levodopa (LEVODOPA, L-DOPA), carbidopa (CARBIDOPA), dopamine or derivatives thereof, preferably levodopa (LEVODOPA, L-DOPA) [ ¹⁸ F] fluoride It is prepared by labeling through a nucleophilic substitution reaction, and the labeling method thereof is according to a known procedure (Source: Appl. Radiat. Isot. 67 2009 1650-1653).

As the [ ¹⁸ F] fluoride source, a fluorine salt which is a compound containing fluorine-18 may be used, and a known fluorine salt may be used. Or the labeling of [ ¹⁸ F] fluoride can achieve radiolabeling with fluorine by electrophilic fluorination using ¹⁸ [F] F fluorine gas, preferably to [ ¹⁸ F] -fluoride ions By nucleophilic substitution of the appropriate leaving group.

Accordingly, [ ¹⁸ F] fluoro-dopa retains the chemical properties of levodopa (LEVODOPA, L-DOPA), which is unstable in aqueous alkaline solutions, oxidized well by oxygen and should be stored at 2-8 ° C. (Https://www.sigmaaldrich.com/content/dam/sigmaaldrich/docs/Sigma/Product_Information_Sheet/d9628pis.pdf; http://www.sigmaaldrich.com/catalog/product/aldrich/333786lang = ko & region = KR). Therefore, [ ¹⁸ F] fluoro-dopa, which has been reported so far due to this chemical property of levodopa, is also difficult to store and use. Since [ ¹⁸ F] fluoro-dopa is unstable in neutral state, in acidic and refrigerated state It is known to be stored and distributed, and to be neutralized for administration to the human body, and to be neutralized immediately before use, and to be used within 2 hours after neutralization. This is also specified in IASOdopa SPC (summary of product characteristics, http://agenceprd.ansm.sante.fr/html/par_eu/20080604_fr328_iasodopa_spc.pdf), a [ ¹⁸ F] fluoro-dopa product manufactured and sold in Europe. It is stated that, after pH neutralization, it must be stored at 2 to 8 ° C. and used within 2 hours after neutralization, and above pH 4.5, [ ¹⁸ F] fluoro-dopa is oxidized.

On the other hand, since [ ¹⁸ F] fluoro-dopa is decomposed by non-enzymatic oxidation 2 hours after synthesis, there is a paper on a method to prevent this (see J NUCL MED 30: 1249-1256). , 1989). These chemical properties of [ ¹⁸ F] fluoro-dopa are different from [ ¹⁸ F] FDG or [ ¹⁸ F] FLT, which are commonly used as PET imaging agents, and [ ¹⁸ F] FDG or [ ¹⁸ F] FLT. In the case of, the chemical properties are not affected by pH.

The inventors of the present invention is ^[18 F] fluoro-Waveguide synthesis after storage pH, hours of use, the ^[18 F] fluoro receiving a lot of effect on the storage temperature reason radiation affecting radiochemical purity since the waveguide synthetic chemical It was found that impurities were produced. Accordingly, the present inventors have studied the [ ¹⁸ F] fluoro-dopa formulation that can be stored at neutral pH, prolonged use time after neutralization, storage at room temperature after neutralization, 5% to 30% (V / V) concentration of the total composition With ethanol; The present invention was completed by confirming that a buffer having a value of pKa 6 to 8.1 at 25 ° C can inhibit the production of radiochemical impurities.

Ethanol can be used to purchase 100% pure ethanol from the manufacturer, it can be used 5% to 30% (V / V) concentration of the total composition. Since the formation of the first and second radiochemical impurities affected by hydrogen ion concentration and storage time, which is detected by HPLC after neutralization from [ ¹⁸ F] fluoro-dopa synthesized by ethanol addition, is inhibited [ ¹⁸ F] ] The radiochemical purity of the fluoro-waveguide can be maintained at least 90% or more.

Buffers with pKa 6 to 8.1 at 25 ° C. can also be purchased from the manufacturer. The buffer having a value of pKa 6.1 to 8.1 at 25 ° C is PBS (PHOSPHATE BUFFERED SALINE), Citrate Buffer (CITRATE BUFFER), MES (2- (NMORPHOLINO) ETHANESULFONIC ACID), BIS-TRIS (2,2-BIS (HYDROXYMETHYL) -2,2 ', 2' '-NITRILOTRIETHANOL) Buffer, MOPSO (3-MORPHOLINO-2-HYDROXYPROPANESULFONIC ACID) Buffer, HEPES (4- (20HYDROXETHYL) -1-PIPERAZINEETHANSFULFONIC ACID) Buffer, and TRIS (TRIS (HYDROXYMET) ) AMINOMETHANE, or TRIZMA®) buffer is at least one selected from the group consisting of.

[ ¹⁸ F] fluoro-waveguided by the addition of a buffer of the above conditions inhibits the formation of a third radiochemical impurity affected by the storage temperature, which is detected by TLC after neutralization from [ ¹⁸ F] fluoro-waveguided The radiochemical purity of may be maintained at least 90% or more.

Accordingly, the composition according to the present invention can exhibit radiochemical purity of at least 90% by inhibiting the generation of impurities for 2 to 6 hours after the synthesis of the [ ¹⁸ F] fluoro-dopa at pH 6-8.

In addition, the composition according to the present invention may exhibit at least 90% of radiochemical purity by inhibiting the generation of impurities for 2 to 6 hours after the synthesis of the [ ¹⁸ F] fluoro-dopa at room temperature.

In addition, the composition according to the present invention can exhibit radiochemical purity of at least 90% by inhibiting the generation of the impurities for 2 to 6 hours after the synthesis of the [ ¹⁸ F] fluoro-dopa at pH 6 ~ 8 and room temperature conditions have.

On the other hand, the [ ¹⁸ F] fluoro-dopa prepared by the above known synthesis method is in an acidic state of pH 2-4, which needs to be adjusted to a pH suitable for human or mammalian administration, for example pH 6-8. Sodium bicarbonate, sodium carbonate or mixtures thereof may be used.

In addition, a composition for stabilizing the radiochemical purity of [ ¹⁸ F] fluoro-dopa according to the present invention is supplied to a clinical syringe or container provided with a seal suitable for single or multiple puncture with a hypodermic needle while maintaining sterile integrity It is provided, for example, in a single vial or multi-use vial. The multi-use vial, like a single-use vial, does not use the medicine contained in one vial to one patient, and discards the rest, but for injection that can use the medicine contained in one vial to two or more patients Refers to a glass container.

The composition for stabilizing the radiochemical purity of [ ¹⁸ F] fluoro-waveguide according to the present invention may be for positron emission tomography (PET) imaging, PET / CT combined with the PET or computed tomography, or the PET and magnetic resonance imaging may be used for imaging such as PET / MRI.

The radiochemical purity (RCP) refers to the ratio of the presence of other radionuclides to the radionuclide of interest, and in the present invention, the RCP is [ ¹⁸ F] fluoro- with respect to the total radioactivity present in the sample. Expressed in% of waveguide activity.

In addition, the present invention provides [ ¹⁸ F] fluoro-dopa; In case the total composition from about 5% to about 30% (V / V) of ethanol and 25 ℃ of concentrations, including the steps of mixing the buffer with a value of pKa 6 to 8.1, inhibit impurities generated for a predetermined period of time the ^[18 F] A method of preparing a composition for stabilizing the radiochemical purity of fluoro-dopa is provided. The same or similar description with respect to the composition is omitted herein.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are provided to illustrate the present invention, and the scope of the present invention is not limited only to the following examples, and those skilled in the art should understand the present invention without departing from the technical spirit of the present invention. Various modifications and variations can be made to the same, which of course fall within the scope of the invention.

Experimental Example 1. Effect of hydrogen ion concentration on the radiochemical purity of [ ¹⁸ F] fluoro-waveguide

[ ¹⁸ F] fluoro-dopa (100% radiochemical purity) was prepared according to a known procedure (Appl. Radiat. Isot. 67 2009 1650-1653) and [ ¹⁸ F] fluoro-dopa prepared above The initial hydrogen ion concentration (100% of radiochemical purity) is 4. This was formulated with physiological saline, and the sodium ion concentration was adjusted to 6, 7, and 8, respectively, followed by HPLC (high performance liquid) every 0 hours, 2 hours, 4 hours, and 6 hours at room temperature (or room temperature). Chromatograph) was used to measure radiochemical purity, and the results are shown in Table 1.

Comparative Example 1. Effect of Hydrogen Ion Concentration on the Radiochemical Purity of [ ¹⁸ F] FDG

[ ¹⁸ F] FDG (100% radiochemical purity) was prepared according to a known procedure (Ind. J. Appl. Radiatl Isot 35 1984 985-986), formulated with physiological saline and hydrogen ion concentration using sodium bicarbonate. After adjusting to 6, 7, and 8, at room temperature (or room temperature) at 0, 2, 4 and 6 hours respectively, radiochemical purity was measured by thin layer chromatography (TLC). As shown in 1.

Comparative Example 2 Effect of Hydrogen Ion Concentration on the Radiochemical Purity of [ ¹⁸ F] FLT

[ ¹⁸ F] FLT (100% radiochemical purity) was prepared according to known procedures (Eur. J. Nucl. Med. Mol. Imaging. 2007, 34, 1406-1409), formulated with physiological saline and bicarbonate at room temperature Adjust the hydrogen ion concentration to 6, 7, and 8 using sodium, and then use the HPLC (High Performance Liquid Chromatograph) at 0, 2, 4, and 6 hours at room temperature (or room temperature). Was measured, and the results are shown in Table 1. The numerical values in Table 1 are in units of hydrogen ion concentration and time, based on 100% of the radiochemical purity of each of the originally prepared [ ¹⁸ F] fluoro-dopa, [ ¹⁸ F] FDG and [ ¹⁸ F] FLT, respectively. Shows the change in radiochemical purity over time.

	[ 18 F] fluoro-dopa			[ 18 F] FDG			[ 18 F] FLT
	pH6	pH7	pH8	pH6	pH7	pH8	pH6	pH7		pH8
0 hours	100	100	99.73	99.07	99.23	99.78	100	100	99.15
2 hours	96.66	92.02	91.14	98.04	100	99.01	100	100	100
4 hours	92.6	78.67	76.58	98.12	99.46	99.89	99.78	100	99.29
6 hours	87.95	63.81	51.78	99.12	98.12	100	100	100	100

As shown in Table 1, [ ¹⁸ F] FDG of Comparative Example 1 and [ ¹⁸ F] FLT of Comparative Example 2 were formulated in physiological saline after synthesis and 90% even if time elapsed at neutral pH (pH 6-8). While it can be used as a radiopharmaceutical with the above radiochemical purity, the [ ¹⁸ F] fluoro-dopa of Experimental Example 1 rapidly decreases over time at a neutral pH (pH 6-8), resulting in a rapid decrease in radiochemical purity for 2 hours. Thereafter it showed radiochemical purity that cannot be used as a radiopharmaceutical. This was due to the characteristics of [ ¹⁸ F] fluoro-dopa, and non-enzymatic oxidation occurred at room temperature and neutral pH, and it was confirmed that it is not worth it as an anti-drug medicine after 2 hours.

For PET diagnosis, it should be maintained at neutral pH, not acidic, for patient administration of [ ¹⁸ F] fluoro-dopa, and for the convenience of storage and distribution there is no need to maintain radiochemical purity for longer periods at room temperature. have.

Experimental Example 2 [ ¹⁸ F] Fluoro-dopa ( ¹⁸ % of radiochemical purity) [ ¹⁸ F] fluoro-dopa (100% of radiochemical purity) was prepared according to a known procedure (see Appl. Radiat). Isot. 67 2009 1650-1653), formulated with physiological saline and adjusted to pH (7) using sodium bicarbonate, followed by HPLC (high performance) at 2 and 6 hours at room temperature (or room temperature). Liquid chromatography was used to determine whether radioactive impurities were generated and the results are shown in FIGS. 1 and 2.

1 is then neutralized after 2 hours ^[18 F] fluoro-a HPLC chromatogram of the waveguide, Figure 2 after 6 hours after neutralization with ^[18 F] fluoro-HPLC chromatogram of the waveguide.

As shown in FIG. 1, the first impurity (IMP 1) was produced when 2 hours had elapsed after neutralizing to pH 7 at room temperature, and after neutralizing to pH 7 at room temperature as shown in FIG. 2. After 6 hours, it was confirmed that the first impurity (IMP 1) and the second impurity (IMP 2) were produced. As shown in Table 1, after 2 hours of neutralization to pH 7 at room temperature, the radiochemical purity of [ ¹⁸ F] fluoro-dopa is 92.02%, and after 6 hours, it is significantly lowered to 63.81%. As time passed after neutralization, it was shown that impurities were generated due to oxidation of [ ¹⁸ F] fluoro-dopa, thereby reducing radiochemical purity.

Experimental Example 3. Effect of Ethanol on the Radiochemical Purity of [ ¹⁸ F] fluoro-dopa

In order to determine the effect of ethanol on the radiochemical purity of [ ¹⁸ F] fluoro-dopa in the composition of the present invention, the following experiment was performed.

[ ¹⁸ F] fluoro-dopa (radiochemical purity of 100%) was prepared according to known procedures under conditions of hydrogen ion concentration 4 (Appl. Radiat. Isot. 67 2009 1650-1653), ethanol (purity 100 %) Was purchased from Merck and used. Thereafter, the [ ¹⁸ F] fluoro-dopa was added to the prepared vial, and then 1.0%, 5.0%, 10.0%, 20.0% and 30.0% (v / v) of ethanol were added to the vial, respectively, relative to the total composition. Neutralize pH to 6, 7, and 8 using sodium bicarbonate, and neutralize pH by performing HPLC (High Performance Liquid Chromatograph) every 0 hours, 2 hours, 4 hours, and 6 hours, respectively. After that, the change in radiochemical purity of [ ¹⁸ F] fluoro-dopa according to ethanol content was examined.

Experimental Example 3-1. When neutralized with hydrogen ion concentration 6

When neutralizing the hydrogen ion concentration to 6, the addition of 1.0%, 5.0%, 10.0%, 20.0% and 30.0% (v / v) of ethanol, respectively, compared to the total composition resulted in the radiochemical purity of [ ¹⁸ F] fluoro-dopa. Looking at the effect on as follows, the ethanol addition (0%) was performed as a control, the results are shown in Table 2.

The numerical values in Table 2 are shown in%, which shows the ethanol addition amount and the change in radiochemical purity over time based on 100% of the radiochemical purity of the originally prepared [ ¹⁸ F] fluoro-dopa.

	Ethanol 0%		Ethanol 1%		Ethanol 5%	Ethanol 10%		Ethanol 20%	Ethanol 30%
0 hours	100	100	100	100	100	100
2 hours	96.66	99.29	100	100	100	100
4 hours	92.6	98.61	100	100	100	100
6 hours	87.95	97.82	100	100	100	100

As shown in Table 2, after neutralization to pH 6, in the case of no ethanol addition (0%), the radiochemical purity began to decrease to 96.66% from 2 hours, then 92.6% after 4 hours, and 87.95 after 6 hours. After 6 hours, the percentage was reduced to less than 90%, the lowest radiochemical purity available for radiopharmaceuticals. On the other hand, when ethanol was added, it showed a radiochemical purity of 90% or more after 6 hours at room temperature after neutralization to pH 6, especially when 5% or more of ethanol was added. It has been found to maintain chemical purity. In addition, Figure 3 is a diagram showing the results of the Table 2, it was confirmed that the radiochemical purity decreases with linearity with time in 0 ~ 1% ethanol content.

As a result, it can be seen that ethanol suppresses the generation of impurities due to oxidation of [ ¹⁸ F] fluoro-dopa over time to maintain radiochemical purity.

Experimental Example 3-2. Neutralized to pH 7.

When the hydrogen ion concentration was neutralized to 7, the addition of 1.0%, 5.0%, 10.0%, 20.0% and 30.0% (v / v) of ethanol, respectively, relative to the total composition resulted in the radiochemical purity of [ ¹⁸ F] fluoro-dopa. Looking at the effect on as follows, ethanol addition (0%) was performed as a control, the results are shown in Table 3.

The numerical values in Table 3 are shown in%, showing the ethanol addition amount and the change in radiochemical purity over time based on 100% of the radiochemical purity of the originally prepared [ ¹⁸ F] fluoro-dopa.

	Ethanol 0%		Ethanol 1%		Ethanol 5%	Ethanol 10%		Ethanol 20%	Ethanol 30%
0 hours	100	100	100	100	100	100
2 hours	92.02	95.97	97.36	98.6	96.38	100
4 hours	78.67	87.6	95.84	97.24	97.72	100
6 hours	63.81	75.64	84.83	96.42	96.77	100

As shown in Table 3, after neutralization to pH 7, in the case of no ethanol addition (0%), the radiochemical purity began to decrease to 95.97% after 2 hours, then 87.6% after 4 hours, and 75.64 after 6 hours. After 4 hours, the percentage was reduced to less than 90%, the lowest radiochemical purity available for radiopharmaceuticals. On the other hand, when ethanol is added, the chemical purity is maintained even after 6 hours at room temperature after neutralization to pH 7. In the case of adding 5% ethanol, the radiochemical purity is maintained at 90% or more until 4 hours. The addition of more than 10% ethanol showed more than 90% radiochemical purity even after 6 hours. In addition, Figure 4 is a diagram showing the results of Table 3, it was confirmed that the ethanol content affects the radiochemical purity according to the linear pattern of the decrease in radiochemical purity according to the ethanol content.

In addition, as shown in Experimental Example 2, in the case of no ethanol addition, after neutralizing to pH 7, impurities were generated after 2 hours and 6 hours at room temperature, and thus the radiochemical purity was lowered. It can be seen that at least 95% is maintained, ethanol inhibits the generation of impurities due to oxidation of [ ¹⁸ F] fluoro-dopa over time to maintain radiochemical purity.

Experimental Example 3-3. When neutralized with hydrogen ion concentration 8

When neutralizing the hydrogen ion concentration to 8, the addition of 1.0%, 5.0%, 10.0%, 20.0% and 30.0% (v / v) of ethanol, respectively, compared to the total composition resulted in the radiochemical purity of [ ¹⁸ F] fluoro-dopa. Looking at the effect on as follows, the ethanol addition (0%) was performed as a control, the results are shown in Table 4.

The numerical values in Table 4 are shown in%, which shows the ethanol addition amount and the change in radiochemical purity over time based on 100% of the radiochemical purity of the originally prepared [ ¹⁸ F] fluoro-dopa.

	Ethanol 0%		Ethanol 1%		Ethanol 5%	Ethanol 10%		Ethanol 20%	Ethanol 30%
0 hours	99.73	100	100	100	100	100
2 hours	91.14	94.48	96.26	97.07	98.31	100
4 hours	76.58	85.9	93.64	97.54	100	98.96
6 hours	51.87	75.76	62.19	96.47	97.42	97.84

As shown in Table 4, after neutralization to pH 8, in the case of no ethanol addition (0%), the radiochemical purity began to decrease to 91.14% from 2 hours, then 76.58% after 4 hours, and 51.87 after 6 hours. After 4 hours, the rate was sharply reduced to less than 90%, the lowest radiochemical purity that can be used as a radiopharmaceutical. On the other hand, when ethanol is added, the chemical purity is maintained even after 6 hours at room temperature after neutralization to pH 8, and when the ethanol is added 5%, the chemical purity is maintained at 90% or higher until 4 hours. The addition of more than 10% of ethanol showed more than 95% of radiochemical purity even after 6 hours. In addition, Figure 5 is a diagram showing the results of the table 4, it was confirmed that the ethanol content affects the radiochemical purity as the linear pattern of the decrease in radiochemical purity according to the ethanol content.

Experimental Example 4. Effect of storage temperature on the radiochemical purity of [ ¹⁸ F] fluoro-waveguide

Experimental Example 4-1. Defluorination phenomenon

After neutralizing the [ ¹⁸ F] fluoro-dopa prepared by adding 5% ethanol under the same conditions as in Experimental Example 3-2 to hydrogen ion concentration of 7 using sodium bicarbonate, after 0 and 15 minutes at room temperature, PET images were taken.

This result is as shown in FIG. As a ^[18 F] fluoro-8 left in the immediately neutralized at room temperature that has elapsed and the PET-up result by using the waveguide preparation, the right 15 minutes at room temperature after neutralization ^[18 F] fluoro-PET using a waveguide formulation This is the result of the shoot. In the case of the left picture, a normal [ ¹⁸ F] fluoro-waveguide image was confirmed, but in the case of the right picture, a bone (see red arrow) that was not visible was captured in the image. As a result, the inventors have confirmed that there is another impurity that is not analyzed by HPLC. That is, when stored at room temperature, it was confirmed that [18 F] fluoride was formed by the DEFLUORINATION phenomenon. Accordingly, in the case of the right picture of FIG. 8, the formed [ ¹⁸ F] fluoride is ingested into the bone, and bones that are not visible are taken on the PET image, which becomes a bad image and requires a retest. Thereby, [ ¹⁸ F] fluoride (defluorine) produced by the defluorine phenomenon is also an impurity, which should also be suppressed.

Experimental Example 4-2. Effect of storage temperature on the radiochemical purity of [ ¹⁸ F] fluoro-waveguides

In order to determine how the storage time at room temperature affects the defluorine phenomenon, 0% (no addition), 10.0% and 20.0% (v / v), respectively, of the total composition under the same conditions as in Experimental Example 3-2. Neutralize the [ ¹⁸ F] fluoro-dopa prepared by the addition of ethanol to a hydrogen ion concentration of 7 using sodium bicarbonate, and then at room temperature for 0 minutes, 10 minutes, 20 minutes, 30 minutes, 60 minutes, 90 minutes, 120 Radiochemical purity at minutes, 180 minutes, 240 minutes, 300 minutes and 360 minutes was measured by thin layer chromatography (TLC). The reason for the measurement using the TLC is to identify a third impurity not analyzed by HPLC as in Experimental Example 4-1.

At this time, if the ethanol is not added, after further neutralizing, 0 minutes, 10 minutes, 20 minutes, 30 minutes, 60 minutes, 90 minutes under refrigerated storage (4 ℃, 2 ~ 8 ℃) and frozen storage (-20 ℃). Radiochemical purity at minutes, 120 minutes, 180 minutes, 240 minutes, 300 minutes and 360 minutes was further measured, and the results are shown in Table 5 below.

Minutes				Ethanol 0% (no addition)			Ethanol 10%		Ethanol 20%
	Neutralization-room temperature	Chinese-Refrigerated	China-Frozen	Neutralization-room temperature	Neutralization-room temperature
0	97.41	98.55	98.23	98.02	98.42
10	89.77	98.22	98.25	97.62	96.05
20	83.20	97.88	98.10	96.77	96.02
30	52.20	96.06	97.20	89.57	83.84
60	50.93	94.76	96.71	81.07	81.04
90	45.64	94.55	96.20	70.09	75.66
120	37.44	91.01	94.75	67.45	77.21
180	35.07	84.58	91.74	59.57	68.25
240	23.95	81.24	85.24	46.70	63.12
300	22.23	79.00	80.20	40.59	58.24
360	16.52	73.66	77.53	34.4	55.56

As shown in Table 5, as a result of measuring the radiochemical purity by using TLC, when ethanol-free was added and stored at room temperature after neutralization, the radiochemical purity was 89.77% after 10 minutes, and rapidly decreased to 16.52% after 6 hours. Could confirm. On the other hand, in the case of refrigeration, even when ethanol-free is added, the radiochemical purity was 90% or less after 3 hours after neutralization, and the radiochemical purity was 90% or less after 4 hours after neutralization in case of refrigeration, [ ¹⁸ F ] In the case of fluoro-wave, the storage temperature was found to affect the radiochemical purity. As a result, the storage temperature was confirmed to affect the production of the third impurity ([ ¹⁸ F] fluoride).

On the other hand, when ethanol is added, when stored at room temperature after neutralization, when the ethanol is added at 10% and 20%, the radiochemical purity is 90% or less after 30 minutes after neutralization. Although it was possible to delay the time indicating that it was confirmed that the effect is not good compared to the case of refrigeration and freezing storage.

6 is a TLC chromatogram of [ ¹⁸ F] fluoro-dopa prepared by adding 10% of ethanol 1 hour after neutralization, and as shown in FIG. 6, a third impurity ([ ¹⁸ F] The production of fluoride, IMP3) could be confirmed. 7 is a diagram showing the results of Table 5 in the drawings, it can be seen that the difference in the amount of decrease in radiochemical purity in the case of cold storage and freezing storage and room temperature storage.

The result of Experiment 4-2 is that the third impurity ([ ¹⁸ F] fluoride) produced by the defluorine phenomenon is not measured by HPLC, but it is regarded as a result detected by TLC, and the formation of the third impurity is ethanol Even if it is added, it can be judged that it is influenced by the storage temperature.

Experimental Example 5. Effect on the radiochemical purity of the [ ¹⁸ F] fluoro-waveguide of the buffer

In order to suppress the generation of the third impurity generated when stored at room temperature as shown in Experimental Example 4 to determine whether it can represent the radiochemical purity usable as a radiopharmaceutical even at room temperature, the buffer of [ ¹⁸ F] fluoro-dopa The effect on radiochemical purity was tested.

As in Experimental Example 3, [ ¹⁸ F] fluoro-dopa (radiochemical purity of 100%) was prepared according to a known procedure under a condition of hydrogen ion concentration 4, and added to a vial, 5.0% (v) of the total composition. / v) ethanol and a buffer having a value of pKa 6 to 8.1 at 25 ° C. and neutralized to pH 7 with sodium bicarbonate, followed by 0, 10, 20, 30, 60, 90, The production of the third impurity was confirmed by measuring radiochemical purity at 120, 180, 240, 300 and 360 minutes using HPLC (High Purity Liquid Chromatography) and TLC (Thin Film Chromatography). The results are shown in Table 6 below. The numerical values of the results in Table 6 are in%, showing the change in radiochemical purity according to the type of buffer added with ethanol based on 100% of the radiochemical purity of the originally prepared [ ¹⁸ F] fluoro-dopa. As a numerical value, the sum of the HPLC measurement value and the TLC measurement value was expressed as the negative value at the initial radiochemical purity of 100%. This can finally confirm whether the production of the first and second impurities measured by HPLC and the third impurities measured by TLC is suppressed.

The buffer having a value of pKa 6 to 8.1 at 25 ° C is PBS (PHOSPHATE BUFFERED SALINE), Citrate Buffer (CITRATE BUFFER), MES (2- (N-MORPHOLINO) ETHANESULFONIC ACID), BIS-TRIS (2,2 -BIS (HYDROXYMETHYL) -2,2 ', 2' '-NITRILOTRIETHANOL) Buffer, MOPSO (3-MORPHOLINO-2-HYDROXYPROPANESULFONIC ACID) Buffer, HEPES (4- (20HYDROXETHYL) -1-PIPERAZINEETHANSFULFONIC ACID) Buffer and TRIS (TRIS (HYDROXYMETHYL) AMINOMETHANE) and each of them was tested.

Minutes	PBS	Citrate	MES	Bis-tris	MOSPO	HEPES		Tris
0	100.00	99.26	99.34	99.89	99.78	99.14	99.76
10	100.00	99.04	99.08	99.79	99.84	98.18	98.65
20	100.00	98.65	98.45	99.34	99.57	99.81	98.76
30	97.41	99.18	98.75	97.34	99.04	98.14	98.04
60	98.62	98.57	98.67	98.67	98.00	97.89	97.65
90	98.91	98.40	98.57	98.51	97.59	98.27	97.14
120	98.72	98.72	96.75	96.37	96.57	97.15	97.86
180	97.41	96.81	97.38	97.51	97.48	96.67	96.37
240	98.62	97.34	96.34	95.67	96.97	95.67	96.48
300	97.66	96.77	95.37	95.31	95.76	96.08	95.71
360	97.51	95.52	95.72	95.04	96.14	95.21	95.07

As shown in Table 6 above, as a result of using a buffer having a value of pKa 6 to 8.1 at 25 ° C with ethanol, even if stored for 6 hours at room temperature after neutralization, it was confirmed that all of the radiochemical purity of 95% or more. . From this, it was confirmed that the defluorine side reaction was suppressed using a buffer to suppress radiochemical impurity (third impurity) generation, thereby maintaining a high level of radiochemical purity of [ ¹⁸ F] fluoro-dopa. In addition, Figure 9 shows the results of Table 6 above by using the ethanol and each buffer of the present invention, even after the storage time at room temperature after neutralization maintains the radiochemical purity of [ ¹⁸ F] fluoro-dopa at least 95% It was clearly confirmed that this was confirmed that this is the result of suppressing the production of the first to third impurities by ethanol and buffer.

The present invention can be used in a composition for stabilizing the radiochemical purity of [ ¹⁸ F] fluoro-dopa and a method for preparing the same.

Claims (10)

1. [ ¹⁸ F] fluoro-dopa;

   Ethanol at a concentration of 5% to 30% (V / V) relative to the total composition;

   Including a buffer having a value of pKa 6 to 8.1 at 25 ℃,

   A composition for stabilizing the radiochemical purity of the [ ¹⁸ F] fluoro-waveguide by inhibiting the generation of impurities for a predetermined time.
2. The method of claim 1,

   The composition,

   at pH 6-8, inhibiting the generation of impurities for 2-6 hours after the synthesis of the [ ¹⁸ F] fluoro-dopa to exhibit at least 90% radiochemical purity.
3. The method according to claim 1 or 2,

   The composition,

   At room temperature, inhibiting the generation of impurities for 2 to 6 hours after the synthesis of the [ ¹⁸ F] fluoro-dopa to exhibit radiochemical purity of at least 90%.
4. The method of claim 3,

   The buffer having a value of pKa 6.1 to 8.1 at 25 ° C,

   PBS (PHOSPHATE BUFFERED SALINE), CITATE Buffer (CITRATE BUFFER), MES (2- (N-MORPHOLINO) ETHANESULFONIC ACID), BIS-TRIS (2,2-BIS (HYDROXYMETHYL) -2,2 ', 2' '- NITRILOTRIETHANOL) buffer, MOPSO (3-MORPHOLINO-2-HYDROXYPROPANESULFONIC ACID) buffer, HEPES (4- (20HYDROXETHYL) -1-PIPERAZINEETHANSFULFONIC ACID) buffer, and TRIS (TRIS (HYDROXYMETHYL) AMINOMETHANE) buffer. It is a composition.
5. The method of claim 4, wherein

   The dopa comprises levodopa (L-dopa), carbadopa, dopamine or derivatives thereof.
6. [ ¹⁸ F] fluoro-dopa;

   Mixing ethanol at a concentration of 5% to 30% (V / V) relative to the total composition and a buffer having a value of pKa 6 to 8.1 at 25 ° C.,

   A method for producing a composition for stabilizing the radiochemical purity of the [ ¹⁸ F] fluoro-waveguide by inhibiting the generation of impurities for a predetermined time.
7. The method of claim 6,

   The composition,

   in that the, ^[18 F] fluoro that to indicate a radiochemical purity of at least 90% by suppressing the impurities generated for two to six hours after synthesis of the waveguide - in the pH 6 ~ 8 wherein the ^[18 F] fluoro-dopa Method for preparing a composition for stabilizing the radiochemical purity of.
8. The method according to claim 6 or 7,

   The composition,

   In that the, ^[18 F] fluoro that to indicate a radiochemical purity of at least 90% by suppressing the impurities generated for two to six hours after synthesis of the waveguide-at room temperature the ^[18 F] fluoro-guided radiation of the chemical Process for preparing a composition to stabilize the purity.
9. The method of claim 8,

   The buffer having a value of pKa 6.1 to 8.1 at 25 ° C,

   PBS (PHOSPHATE BUFFERED SALINE), CITATE Buffer (CITRATE BUFFER), MES (2- (N-MORPHOLINO) ETHANESULFONIC ACID), BIS-TRIS (2,2-BIS (HYDROXYMETHYL) -2,2 ', 2''- NITRILOTRIETHANOL) buffer, MOPSO (3-MORPHOLINO-2-HYDROXYPROPANESULFONIC ACID) buffer, HEPES (4- (20HYDROXETHYL) -1-PIPERAZINEETHANSFULFONIC ACID) buffer, and TRIS (TRIS (HYDROXYMETHYL) AMINOMETHANE) buffer. A process for the preparation of a composition for stabilizing the radiochemical purity of [ ¹⁸ F] fluoro-waveguide.
10. The method of claim 9,

    The dopa comprises a levodopa (L-dopa), carbadopa, dopamine or derivatives thereof, the method of producing a composition for stabilizing the radiochemical purity of [ ¹⁸ F] fluoro-dopa.

Images