Formulations for radiotherapy and diagnostic imaging

Abstract

The present invention relates to formulations for radiotherapy and diagnostic imaging. In particular, the present invention relates to formulations of radiolabeled compounds for use in radiotherapy and diagnostic imaging.

Description

[0001] This application is a divisional application of Chinese patent application No. 201780081459.0, filed on November 2, 2017, entitled "Preparation for Radiotherapy and Diagnostic Imaging". Technical Field

[0002] This invention relates to formulations of radiolabeled compounds for use in radiotherapy and diagnostic imaging. Background Technology

[0003] Radiolabeled compounds or ligands can be used as radiopharmaceuticals in applications such as radiotherapy or diagnostic imaging. Radiolabeled compounds have particular uses where they exhibit a tendency to selectively target specific sites (e.g., specific receptors) in vivo and subsequently deliver a radioisotope to the desired site of action. This requires the ligand to contain a component that chelates the radioisotope and additional components that target the desired site.

[0004] One known problem associated with this ligand is the premature dissociation of the radioisotope before the ligand-radioisotope complex reaches its site of action. This not only reduces the efficacy of the complex, but also allows the radioisotope to leak into areas where radiation therapy is not needed, potentially leading to adverse consequences.

[0005] The dissociation of a radioactive isotope from its ligand can occur via transchelation, in which the radioactive isotope is transferred within the body to another biological ligand. This, too, leads to reduced therapeutic efficacy and can result in the radioactive isotope being delivered to areas where treatment is not desired.

[0006] The ligands to be radiolabeled and the radioisotopes are typically stored in separate containers and transported to patients to minimize the aforementioned issues related to pre-administration dissociation. The ligands can be transported as lyophilized powders at low temperatures, thus prolonging the stability of the compound. The radioisotopes can then be combined with the ligands to form a radiopharmaceutical prior to administration, which can help minimize the dissociation of the radioisotopes before the complex reaches its site of action.

[0007] Another problem associated with radiolabeled compounds is that the use of radioisotopes can lead to radiodecomposition, or ligand destruction. When a radioisotope undergoes spontaneous decay and subsequent radioactive release, the energy may be sufficient to induce bond cleavage and lead to subsequent ligand destruction. In addition to reduced efficacy of the radiopharmaceutical, the release of the radioisotope can result in radiation being delivered to undesirable sites.

[0008] Because many radiopharmaceuticals are designed for parenteral administration (i.e., non-oral administration) and are typically administered as solutions, the ligand itself must be soluble in pharmaceutically acceptable solvents or carriers. As is known in the art, the solubility of a particular compound in any given solvent can be unpredictable. While the solubility of a particular compound in a particular solvent may be known, the solubility of analogues of the compound can vary considerably in different solvent systems. This presents a challenge for those seeking to develop formulations of compounds, particularly pharmaceutically acceptable injectable formulations.

[0009] Pharmaceutical formulations typically contain one or more excipients that affect the compound in certain ways, such as enhancing its solubility or increasing its stability in solution. Alternatively, additional excipients may be used to provide other characteristics to the formulation, such as preservatives, buffers, etc.

[0010] Although thousands of ligand-radioisotope complex formulations have been documented, it cannot be expected that the excipients used in these formulations will provide the solubility and bioavailability required for any newly developed complex. Furthermore, it cannot be expected that specific combinations of excipients will further prevent or minimize the dissociation of the radioisotope or minimize radiodecomposition.

[0011] Therefore, there is a need to tailor formulations of desired ligand-radioisotope complexes to exhibit the necessary stability associated with radiodecomposition and radioisotope dissociation, while also being pharmaceutically acceptable. This invention seeks to address these problems associated with specific ligand complexes. Summary of the Invention

[0012] In one aspect of the invention, an aqueous formulation for parenteral administration is provided, comprising a compound of formula (I) or a salt thereof complexed with Cu ions: Formula (I) The formulation further comprises: Approximately 7% to approximately 13% (v / v) ethanol; Sodium chloride, approximately 0.3% to approximately 1.2% (w / v); About 0.02 to about 0.1% (w / v) gentianic acid or its salt; The formulation described therein has a pH of about 4 to about 8.

[0013] In another aspect of the invention, an aqueous formulation for parenteral administration is provided, comprising a compound of formula (I) or a salt thereof complexed with Cu ions: Formula (I) The formulation further comprises: Approximately 7% to approximately 13% (v / v) ethanol; Sodium chloride, approximately 0.3% to approximately 1.2% (w / v); About 0.02 to about 0.1% (w / v) gentianic acid or its salts; and Approximately 1.0 to approximately 4.0 mg / mL of L-methionine or its salts; The formulation described therein has a pH of about 4 to about 8.

[0014] In one implementation scheme and relating to both of the above aspects, the compound of formula (I) is provided as an acetate.

[0015] According to another aspect of the present invention, a method is provided for preparing an aqueous formulation comprising a compound of formula (I) complexed with Cu ions, the method comprising the following steps: i) Prepare a buffer solution of acetate, wherein the buffer solution further comprises ethanol and gentianic acid or a salt thereof; ii) Dissolve the compound of formula (I) or a salt thereof in the buffer solution obtained in step i); iii) Add the Cu ion solution to the solution obtained in step ii); iv) Filter the solution obtained in step iii) onto the stationary phase; and v) Wash the stationary phase from step iv) with ethanol and brine; To recover aqueous formulations containing compounds of formula (I) or their salts that are complexed with Cu ions.

[0016] According to another aspect of the present invention, a method is provided for preparing an aqueous formulation comprising a compound of formula (I) complexed with Cu ions, the method comprising the following steps: i) Prepare a buffer solution of acetate, wherein the buffer solution further comprises ethanol and gentianic acid or a salt thereof; ii) Dissolve the compound of formula (I) or a salt thereof in the buffer solution obtained in step i); iii) Add the Cu ion solution to the solution obtained in step ii); iv) Filter the solution obtained in step iii) onto the stationary phase; and v) Wash the stationary phase from step iv) with ethanol and saline solution into a vial containing a solution of L-methionine or its salt; To recover aqueous formulations containing compounds of formula (I) or their salts that are complexed with Cu ions.

[0017] According to another aspect of the invention, an aqueous formulation prepared by the method defined in the foregoing aspects is provided.

[0018] The aqueous formulation of the present invention can also be prepared by providing certain components of the formulation as kit ofparts, wherein the kit contains at least one compound of formula (I) or a salt thereof, and Cu ions intended to complex with the compound of formula (I), wherein the compound of formula (I) or a salt thereof and the Cu ions are provided separately in the kit and can be combined prior to application to form the complex mentioned above.

[0019] Therefore, in another aspect, the present invention provides a kit for preparing an aqueous formulation for parenteral administration comprising a compound of formula (I) or a salt thereof complexed with Cu ions, the kit comprising: A container containing a lyophilized compound of formula (I) or a salt thereof; Formula (I) Containers containing solutions of Cu ions; and Instructions for use in preparing aqueous formulations as defined in the foregoing include the addition of a buffered solution of ethanol, sodium chloride and gentisic acid, or a salt thereof.

[0020] In another aspect, the present invention provides a kit for preparing an aqueous formulation for parenteral administration comprising a compound of formula (I) or a salt thereof complexed with Cu ions, the kit comprising: A container containing a lyophilized compound of formula (I) or a salt thereof; Formula (I) Containers containing solutions of Cu ions; and Instructions for use in preparing aqueous formulations as defined above include the addition of a buffered solution of ethanol, sodium chloride, gentisic acid or a salt thereof, and L-methionine or a salt thereof.

[0021] Another aspect of the present invention provides a kit for preparing an aqueous formulation for parenteral administration as defined in the foregoing aspects, the kit comprising: A container containing a lyophilized compound of formula (I) or a salt thereof; Formula (I) Container for a solution containing Cu ions; A container containing a buffer solution of ethanol, sodium chloride, and gentianic acid or its salts; and Instructions for use in the preparation of aqueous formulations as defined in the foregoing aspects.

[0022] Another aspect of the present invention provides a kit for preparing an aqueous formulation for parenteral administration as mentioned above, the kit comprising: A container containing a lyophilized compound of formula (I) or a salt thereof; Formula (I) Container for a solution containing Cu ions; A container containing a buffer solution of ethanol, sodium chloride, gentianic acid or a salt thereof, and L-methionine or a salt thereof; and Instructions for use in the preparation of aqueous formulations as defined in the foregoing aspects.

[0023] Another aspect of the invention provides a method for radiographic imaging, diagnosis, or treatment of cancer, the method comprising administering an aqueous formulation as defined in the foregoing aspect to a subject in need of it. Attached Figure Description

[0024] Figure 1 Area percentage report, using gamma scintillation detector-high performance liquid chromatography (HPLC) to analyze low doses of Example 1 immediately after preparation. 64 The Cu-SARTATE formulation (radiochemical yield = 606 MBq) showed 97.3% detection rate. 64 Cu as 64 Cu-SARTATE exists.

[0025] Figure 2 Using a gamma scintillation detector to measure the low dose of Example 1 over 24 hours 64 The chromatograms of repeated HPLC analysis of the Cu-SARTATE formulation show that... 64 The radiochemical purity of Cu-SARTATE remained stable over time (> 90%).

[0026] Figure 3 Area percentage report, high dose of Example 2 analyzed immediately after preparation using gamma scintillation detector-HPLC. 64The Cu-SARTATE formulation (radiochemical yield = 3500 MBq) showed 98.2% detection rate. 64 Cu as 64 Cu-SARTATE exists.

[0027] Figure 4 High doses of Example 2 were administered using a gamma scintillation detector over 45 hours. 64 The chromatograms of repeated HPLC analysis of the Cu-SARTATE formulation show that... 64 The radiochemical purity of Cu-SARTATE remained stable over time (> 90%).

[0028] Figure 5 Area percentage report, analyzed immediately after preparation using gamma scintillation detector-HPLC in Example 3. 67 The Cu-SARTATE formulation (radiochemical yield = 3922 MBq) showed 98.6% detection rate. 67 Cu as 67 Cu-SARTATE exists.

[0029] Figure 6 Example 3 was tested using a gamma scintillation detector over 11 hours. 67 The chromatograms of repeated HPLC analysis of the Cu-SARTATE formulation show that... 67 The radiochemical purity of Cu-SARTATE remained stable over time (> 90%).

[0030] Figure 7 After incubation in fresh human serum for 43 hours, the effect on Example 2 was investigated. 64 A chromatogram of repeated HPLC analysis of the Cu-SARTATE formulation.

[0031] Figure 8 : 64 Cu-SARTATE in SSTR2 overexpressing cell line A427-7 (solid symbol) and cell line with excessive Tyr 3 -Octrete acid (hollow symbol) is internalized in vitro to increase incubation time.

[0032] Figure 9 : 64 Cu-SARTATE in SSTR2 overexpressing cell line A427-7 (solid symbol) and cell line with excessive Tyr 3 -Octreotide (hollow symbol) binds to the cell surface to increase incubation time.

[0033] Figure 10 : 64Comparison of normalized uptake of Cu-SARTATE in A427-7 and A427 parental cell lines within 2 hours (p < 0.0001).

[0034] Figure 11 : 64 In vivo biodistribution of Cu-SARTATE in selected tissues from Balb / c mice carrying A427-7 tumors at 2 and 24 hours. Biodistribution was also assessed at 2 hours via co-injection of an overdose of Tyr. 3 -Octreotide was used for blocking studies to confirm 64 Cu-SARTATE's specificity for SSTR2.

[0035] Figure 12 : 64 In vivo PET imaging of Cu-SARTATE with and without co-injection of excessive Tyr 3 -Octreotide acid, during injection 64 Small animal PET maximum intensity projection images of Balb / c mice carrying A427-7 tumors at 2 hours and 24 hours after Cu-SARTATE. Detailed Implementation

[0036] This invention relates to stable formulations of specific radioisotope-ligand complexes. The inventors have discovered that the formulations of the complexes disclosed herein minimize the dissociation of the radioisotope from the ligand and / or minimize radioactive decomposition of the ligand caused by the radioisotope.

[0037] The formulations of the radioisotope-ligand complexes mentioned in this article are stable in solution and under physiological conditions over a period of time. The stability of the formulation involves the stability of the complex, where the radioisotope may dissociate or the complex may undergo radiodecomposition. The stability of the complex can be measured by considering the radiochemical purity of the formulation. Radiochemical purity is defined as the amount of radioisotope complexed with sarcophagine ligands, expressed as a percentage of the total amount of radioisotope present in the formulation. The radioisotope may exist in the formulation as a complex with sarcophagine ligands, as a free radioisotope, or as part of the radiodecomposition products.

[0038] It has been previously discovered that ligands containing octreotate target somatostatin receptors, namely type 2 (SSTR2) and type 5 (SSTR5) receptors. Examples of octreotate-containing ligands are MeCOSar-octreotate or MeCOSar-D-Phe-Cys-Tyr-D-Trp-Lys-Thr-Cys-Thr-OH, where MeCOSar is the macrocyclic sarcophagine ligand 5-[[8-amino-3,6,10,13,19-hexaazabicyclo[6.6.6]eicosano-1-yl]amino]-5-oxo-pentyl, and octreotate is D-Phe-Cys-Tyr-D-Trp-Lys-Thr-Cys-Thr-OH. Those skilled in the art will understand that octreotide acid is a cyclic octapeptide and is derived from the corresponding linear peptide by forming Cys-Cys disulfide bonds. Those skilled in the art will also understand that sarcophagine (“sar”) is a nitrogen-containing hexadecimal macrocyclic ligand capable of complexing donor atoms, such as transition metal ions, and in the case of this invention, Cu ions.

[0039] MeCOSar-octreotide acid (also referred to as "SARTATE" in this paper) is also shown in formula (I): Formula (I) Compound (I) can be prepared via a coupling reaction between a sarcophagine ligand and an octreotide cyclic peptide, wherein the macrocyclic sarcophagine and octreotide fragments are synthesized separately prior to coupling. The sarcophagine of formula (I) is itself derived from an amino-terminated macrocyclic ligand coupled to an aliphatic carboxylic acid ester group. Previously... Dalton Trans. The synthetic route for obtaining the compound of formula (I) and components sarcophagine and octreotide acid fragment is disclosed in 2015, 43, 1386.

[0040] The present invention also contemplates the use of pharmaceutically acceptable salts of compounds of formula (I) as part of the claimed formulation. Examples of pharmaceutically acceptable salts of compounds of formula (I) may include the corresponding acetate, sodium, hydrochloride, potassium, magnesium, calcium, or ammonium salts. In one embodiment, the compound of formula (I) is provided as an acetate.

[0041] The applicable formulations of the present invention comprise a complex of a compound of formula (I) or a salt thereof with a radioactive isotope. The radioactive isotope may also be referred to as a radionuclide and may be a metal or a metal ion. It has been found that the ligands of this specification are effective in complexing copper ions, particularly Cu. 2+ Particular success has been achieved with ions. Previously, [this had already been done]. Dalton Trans. A complex of formula (I) comprising a radioactive isotope of copper ions is disclosed in 2015, 43,1386. Those skilled in the art will also understand that a complex of formula (I) and a radioactive isotope can be obtained by contacting a compound of formula (I) or a salt thereof with the radioactive isotope to be complexed, thereby complexing the compound of formula (I) or a salt thereof with the radioactive isotope. This may involve mixing the compound of formula (I) or a salt thereof with the radioactive isotope in a suitable solvent system (as specifically described herein).

[0042] In one embodiment, the ligand complexes with Cu ions. The copper ions can be radioactive, and therefore a radionuclide or radioisotope of copper. In one embodiment, the ligand... 60 Cu complexation. In another embodiment, the ligand and... 61 Cu complexation. In another embodiment, the ligand and... 64 Cu complexation. In another embodiment, the ligand and... 67 Cu complexation. In a preferred embodiment, the ligand and... 64 Cu complexation. In another preferred embodiment, the ligand and... 67 Cu complexation.

[0043] The formulation of the present invention comprises ethanol as a component. The ethanol used in the formulation may be anhydrous ethanol. Alternatively, the ethanol used in the formulation may not be dried and may be hydrated. Pharmaceutical grade ethanol is preferred. The presence of ethanol in the formulation may further help prevent radiodegradation of the radiolabeled complex of formula (I).

[0044] In one embodiment, the ethanol content in the formulation is from about 7% to about 13% (v / v). In another embodiment, the ethanol content in the formulation is about 7% (v / v). In another embodiment, the ethanol content in the formulation is about 8% (v / v). In another embodiment, the ethanol content in the formulation is about 9% (v / v). In another embodiment, the ethanol content in the formulation is about 10% (v / v). In another embodiment, the ethanol content in the formulation is about 11% (v / v). In another embodiment, the ethanol content in the formulation is about 12% (v / v). In another embodiment, the ethanol content in the formulation is about 13% (v / v). In a preferred embodiment, the ethanol content in the formulation is about 10% (v / v). In other embodiments, the invention also covers ethanol in the range of the amounts mentioned above.

[0045] The formulation of the present invention further comprises sodium chloride as a component. The sodium chloride in the formulation of the present invention can be provided as a saline solution. A saline solution is defined as an aqueous solution of sodium chloride. For example, physiological saline is defined as an aqueous solution of sodium chloride with a concentration of 0.9% (w / v). In one embodiment of the present invention, the sodium chloride in the formulation is provided by a saline solution.

[0046] In one embodiment, sodium chloride is present in the formulation at an amount of about 0.6% to 1.2% (w / v). In another embodiment, sodium chloride is present at an amount of about 0.6% (w / v). In another embodiment, sodium chloride is present at an amount of about 0.7% (w / v). In another embodiment, sodium chloride is present at an amount of about 0.8% (w / v). In another embodiment, sodium chloride is present at an amount of about 0.9% (w / v). In another embodiment, sodium chloride is present at an amount of about 1.0% (w / v). In another embodiment, sodium chloride is present at an amount of about 1.1% (w / v). In another embodiment, sodium chloride is present at an amount of about 1.2% (w / v). In a preferred embodiment, sodium chloride is present in the formulation at an amount of about 0.9% (w / v). In other embodiments, the invention also covers sodium chloride in the range of the amounts mentioned above.

[0047] The formulations of the present invention comprise gentianic acid or a pharmaceutically acceptable salt thereof and / or hydrate as a component. Gentianic acid is also known as 2,5-dihydroxybenzoic acid, 5-hydroxysalicylic acid, or hydroquinone carboxylic acid. Salts of gentianic acid may include sodium salts and sodium salt hydrates. Where applicable, any reference to gentianic acid may include a reference to its salts. The inventors have confirmed that gentianic acid or its salts, in formulations, help prevent or minimize the radiodegradation of the radiolabeled complex of formula (I).

[0048] In one embodiment, gentic acid or a salt thereof is present in the formulation at about 0.02% to about 0.1% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.02% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.025% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.03% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.035% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.04% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.045% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.05% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.055% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.6% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.065% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.07% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.075% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.08% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.085% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.09% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.095% (w / v). In another embodiment, gentic acid or a salt thereof is present in the formulation at about 0.1% (w / v). In other embodiments, the invention also covers gentic acid or its salts within the range of amounts mentioned above. In a preferred embodiment, the presence of gentic acid or its salts in the formulation is not more than 0.056% (w / v).

[0049] The formulations of the present invention have a pH of about 4 to about 8. Those skilled in the art will understand that the pH of the formulation is an inherent characteristic of the formulation and is attributed to the combination of the compound of formula (I) or its complexes and the remaining excipients of the formulation. The inventors have discovered that this pH range provides optimal radiolabeling efficiency.

[0050] In one embodiment, the pH of the formulation is from about 4 to about 8. In one embodiment, the pH of the formulation is about 4. In another embodiment, the pH of the formulation is about 4.5. In another embodiment, the pH of the formulation is about 5.0. In another embodiment, the pH of the formulation is about 5.5. In another embodiment, the pH of the formulation is about 5.6. In another embodiment, the pH of the formulation is about 5.7. In another embodiment, the pH of the formulation is about 5.8. In another embodiment, the pH of the formulation is about 5.9. In another embodiment, the pH of the formulation is about 6.0. In another embodiment, the pH of the formulation is about 6.1. In another embodiment, the pH of the formulation is about 6.2. In another embodiment, the pH of the formulation is about 6.3. In another embodiment, the pH of the formulation is about 6.4. In another embodiment, the pH of the formulation is about 6.5. In another embodiment, the pH of the formulation is about 7.0. In another embodiment, the pH of the formulation is about 7.5. In another embodiment, the pH of the formulation is about 8.0. In a preferred embodiment, the pH of the formulation is about 6.0.

[0051] In a preferred embodiment, the aqueous formulation of the present invention comprises a compound of formula (I) or a salt thereof complexed with Cu ions, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride, and about 0.06% gentic acid or a salt thereof, wherein the formulation has a pH of about 6.0. In another embodiment, the aqueous formulation of the present invention comprises a compound of formula (I) or a salt thereof complexed with Cu ions, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride, and no more than 0.056% gentic acid or a salt thereof, wherein the formulation has a pH of about 6.0. In a further embodiment, the aqueous formulation of the present invention comprises a compound of formula (I) or a salt thereof complexed with Cu ions, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride, and 0.056% gentic acid or a salt thereof, wherein the formulation has a pH of about 6.0. Those skilled in the art will understand that the amount of the formula (I)-Cu ion complex present in the aqueous formulation can be varied to suit different needs.

[0052] In one embodiment, the aqueous formulation of the present invention comprises with 64 A Cu-ion-complexed compound of formula (I) or a salt thereof, about 10% ethanol, about 0.9% (w / v) sodium chloride, and about 0.06% gentian acid or a salt thereof, wherein said formulation has a pH of about 6.0. In one embodiment, the aqueous formulation of the present invention comprises with... 64A Cu-ion-complexed compound of formula (I) or a salt thereof, about 10% ethanol, about 0.9% (w / v) sodium chloride, and no more than 0.056% gentian acid or a salt thereof, wherein said formulation has a pH of about 6.0. In a further embodiment, the aqueous formulation of the present invention comprises with 64 A Cu ion-complexed compound of formula (I) or a salt thereof, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride and 0.056% gentianic acid or a salt thereof, wherein said formulation has a pH of about 6.0.

[0053] In one embodiment, the aqueous formulation of the present invention comprises with 67 A Cu-ion-complexed compound of formula (I) or a salt thereof, about 10% ethanol, about 0.9% (w / v) sodium chloride, and about 0.06% gentian acid or a salt thereof, wherein said formulation has a pH of about 6.0. In one embodiment, the aqueous formulation of the present invention comprises with... 67 A Cu-ion-complexed compound of formula (I) or a salt thereof, about 10% ethanol, about 0.9% (w / v) sodium chloride, and no more than 0.056% gentian acid or a salt thereof, wherein said formulation has a pH of about 6.0. In a further embodiment, the aqueous formulation of the present invention comprises with 67 A Cu ion-complexed compound of formula (I) or a salt thereof, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride and 0.056% gentianic acid or a salt thereof, wherein said formulation has a pH of about 6.0.

[0054] In one embodiment, the aqueous formulation of the present invention comprises with 64 A Cu-ion-complexed compound of formula (I) as an acetate, about 10% ethanol, about 0.9% (w / v) sodium chloride, and about 0.06% gentian acid or a salt thereof, wherein the formulation has a pH of about 6.0. In another embodiment, the aqueous formulation of the present invention comprises with... 64 A Cu-ion-complexed compound of formula (I) as an acetate, about 10% ethanol, about 0.9% (w / v) sodium chloride, and about 0.056% gentian acid or a salt thereof, wherein the formulation has a pH of about 6.0. In another embodiment, the aqueous formulation of the present invention comprises with... 64 The Cu ion-complexed compound of formula (I) as an acetate, about 10% ethanol, about 0.9% (w / v) sodium chloride and no more than 0.056% gentian acid or a salt thereof, wherein the formulation has a pH of about 6.0.

[0055] In one embodiment, the aqueous formulation of the present invention comprises with 67A Cu-ion-complexed compound of formula (I) as an acetate, about 10% ethanol, about 0.9% (w / v) sodium chloride, and about 0.06% gentian acid or a salt thereof, wherein the formulation has a pH of about 6.0. In another embodiment, the aqueous formulation of the present invention comprises with... 67 A Cu-ion-complexed compound of formula (I) as an acetate, about 10% ethanol, about 0.9% (w / v) sodium chloride, and about 0.056% gentian acid or a salt thereof, wherein the formulation has a pH of about 6.0. In another embodiment, the aqueous formulation of the present invention comprises with... 67 The Cu ion-complexed compound of formula (I) as an acetate, about 10% ethanol, about 0.9% (w / v) sodium chloride and no more than 0.056% gentian acid or a salt thereof, wherein the formulation has a pH of about 6.0.

[0056] The aqueous formulation of the present invention may also contain an acetate as a buffer salt. The acetate may be ammonium acetate or sodium acetate.

[0057] The inventors have also discovered that the formulation can be further stabilized by adding L-methionine or a salt thereof. Adding L-methionine to a formulation comprising a compound of formula (I), ethanol, sodium chloride, and gentianic acid or a salt thereof further enhances the stability of the formulation by preventing or minimizing the radiodecomposition of the radiolabeled complex of formula (I). The inventors have also discovered that adding L-methionine to a formulation comprising a compound of formula (I) and Cu ions yields a formulation with higher initial radioactivity, wherein the Cu ions are radioactive isotopes of Cu.

[0058] Therefore, the present invention also provides an aqueous formulation for parenteral administration, comprising a compound of formula (I) or a salt thereof complexed with Cu ions: Formula (I) The formulation further comprises: Approximately 7% to approximately 13% (v / v) ethanol; Sodium chloride, approximately 0.3% to approximately 1.2% (w / v); About 0.02 to about 0.1% (w / v) gentianic acid or its salts; and Approximately 1 to approximately 4 mg / mL of L-methionine or its salts; The formulation described therein has a pH of about 4 to about 8.

[0059] In one embodiment, L-methionine or a salt thereof is present in the formulation at an amount of about 1 mg / mL to about 4 mg / mL. In one embodiment, L-methionine or a salt thereof is present in the formulation at an amount of about 1.0 mg / mL. In another embodiment, L-methionine or a salt thereof is present in the formulation at an amount of about 1.5 mg / mL. In another embodiment, L-methionine or a salt thereof is present in the formulation at an amount of about 2.0 mg / mL. In another embodiment, L-methionine or a salt thereof is present in the formulation at an amount of about 2.5 mg / mL. In another embodiment, L-methionine or a salt thereof is present in the formulation at an amount of about 3.0 mg / mL. In another embodiment, L-methionine or a salt thereof is present in the formulation at an amount of about 3.5 mg / mL. In another embodiment, L-methionine or a salt thereof is present in the formulation at an amount of about 4.0 mg / mL.

[0060] In a further embodiment, the aqueous formulation of the present invention comprises a compound of formula (I) or a salt thereof complexed with Cu ions, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride, about 0.06% gentic acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein the formulation has a pH of about 6.0. In another embodiment, the aqueous formulation of the present invention comprises a compound of formula (I) or a salt thereof complexed with Cu ions, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride, not more than 0.056% gentic acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein the formulation has a pH of about 6.0. In a further embodiment, the aqueous formulation of the present invention comprises a compound of formula (I) or a salt thereof complexed with Cu ions, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride, 0.056% gentianic acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein the formulation has a pH of about 6.0. Those skilled in the art will understand that the amount of the formula (I)-Cu ion complex present in the aqueous formulation can be varied to suit different needs.

[0061] In a further embodiment, the aqueous formulation of the present invention comprises with 64 A Cu ion-complexed compound of formula (I) or a salt thereof, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride, about 0.06% gentianic acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein said formulation has a pH of about 6.0. In one embodiment, the aqueous formulation of the present invention comprises with 64A Cu ion-complexed compound of formula (I) or a salt thereof, about 10% (v / v) ethanol, not more than 0.9% (w / v) sodium chloride, not more than 0.056% gentianic acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein said formulation has a pH of about 6.0. In a further embodiment, the aqueous formulation of the present invention comprises with 64 The formulation comprises a Cu ion-encapsulated compound of formula (I) or a salt thereof, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride, about 0.056% gentianic acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein the formulation has a pH of about 6.0.

[0062] In a further embodiment, the aqueous formulation of the present invention comprises with 67 A Cu ion-complexed compound of formula (I) or a salt thereof, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride, about 0.06% gentianic acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein said formulation has a pH of about 6.0. In one embodiment, the aqueous formulation of the present invention comprises with 67 A Cu ion-complexed compound of formula (I) or a salt thereof, about 10% (v / v) ethanol, not more than 0.9% (w / v) sodium chloride, not more than 0.056% gentianic acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein said formulation has a pH of about 6.0. In a further embodiment, the aqueous formulation of the present invention comprises with 67 A Cu ion-complexed compound of formula (I) or a salt thereof, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride, about 0.056% gentianic acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein the formulation has a pH of about 6.0. In a further embodiment, the aqueous formulation of the present invention comprises with 67 The formulation comprises a Cu ion-encapsulated compound of formula (I) or a salt thereof, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride, about 0.056% gentianic acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein the formulation has a pH of about 6.0.

[0063] In a further embodiment, the aqueous formulation of the present invention comprises with 64 A Cu-ion-complexed compound of formula (I) as an acetate, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride, about 0.06% gentianic acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein the formulation has a pH of about 6.0. In another embodiment, the aqueous formulation of the present invention comprises with 64A Cu-ion-complexed compound of formula (I) as an acetate, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride, about 0.056% gentianic acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein the formulation has a pH of about 6.0. In another embodiment, the aqueous formulation of the present invention comprises with... 64 The Cu ion-complexed compound of formula (I) as an acetate, about 10% ethanol, about 0.9% (w / v) sodium chloride, not more than 0.056% gentian acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein the formulation has a pH of about 6.0.

[0064] In a further embodiment, the aqueous formulation of the present invention comprises with 67 A Cu-ion-complexed compound of formula (I) as an acetate, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride, about 0.06% gentianic acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein the formulation has a pH of about 6.0. In another embodiment, the aqueous formulation of the present invention comprises with 67 A Cu-ion-complexed compound of formula (I) as an acetate, about 10% (v / v) ethanol, about 0.9% (w / v) sodium chloride, about 0.056% gentianic acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein the formulation has a pH of about 6.0. In another embodiment, the aqueous formulation of the present invention comprises with... 67 The Cu ion-complexed compound of formula (I) as an acetate, about 10% ethanol, about 0.9% (w / v) sodium chloride, not more than 0.056% gentian acid or a salt thereof, and about 2.5 mg / mL L-methionine or a salt thereof, wherein the formulation has a pH of about 6.0.

[0065] According to the present invention, 64 Formulations of the complex of Cu and compound (I) can maintain at least approximately 90% radiochemical purity for at least 45 hours. This means that at least approximately 90% of the components present in the formulation remain radiochemically pure after preparation. 64 The radioactive Cu isotope complexes with the compound of formula (I) or its salt for at least 45 hours. When present in the formulation... 64 When the radioactive Cu isotope is not complexed with the compound of formula (I) or its salt, 64 Radioactive Cu isotopes can be used as free... 64 Cu ions may exist as part of the radiodecomposition products.

[0066] In one embodiment, approximately 45 hours after formulation preparation, the present invention comprises... 64The formulation of Cu and a complex of a compound of formula (I) or a salt thereof has a radiochemical purity of about 90%. In another embodiment, the present invention comprises, approximately 45 hours after formulation preparation, [the following is a description of the process:] 64 The formulation of Cu and a complex of a compound of formula (I) or a salt thereof has a radiochemical purity of about 91%. In another embodiment, the present invention comprises, approximately 45 hours after formulation preparation, [the following is a description of the process:] 64 The radiochemical purity of preparations of Cu and complexes of compounds of formula (I) or their salts is approximately 92%.

[0067] In another embodiment, the present invention comprises approximately 45 hours after formulation preparation. 64 The formulation of Cu and a complex of a compound of formula (I) or a salt thereof has a radiochemical purity of about 93%. In another embodiment, the present invention comprises, approximately 45 hours after formulation preparation, [the following is a description of the process:] 64 The formulation of Cu and a complex of a compound of formula (I) or a salt thereof has a radiochemical purity of about 94%. In another embodiment, the present invention comprises, approximately 45 hours after formulation preparation, [the following is a description of the process:] 64 The formulation of Cu and a complex of a compound of formula (I) or a salt thereof has a radiochemical purity of about 95%. In another embodiment, the present invention comprises, approximately 45 hours after formulation preparation, [the following is a description of the process:] 64 The formulation of Cu and a complex of a compound of formula (I) or a salt thereof has a radiochemical purity of about 96%. In another embodiment, the present invention comprises, approximately 45 hours after formulation preparation, [the following is a description of the process:] 64 The formulation of Cu and a complex of a compound of formula (I) or a salt thereof has a radiochemical purity of about 97%. In another embodiment, the present invention comprises, approximately 45 hours after formulation preparation, [the following is a description of the process:] 64 The formulation of Cu and a complex of a compound of formula (I) or a salt thereof has a radiochemical purity of about 98%. In another embodiment, the present invention comprises, approximately 45 hours after formulation preparation, [the following is a description of the process:] 64 The radiochemical purity of preparations of Cu and complexes of compounds of formula (I) or their salts is approximately 99%.

[0068] In one embodiment, the present invention includes 64 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is approximately 99% immediately after formulation preparation. In another embodiment, the present invention comprises... 64 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% about 1 hour after formulation preparation. In another embodiment, the present invention comprises 64The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% about 3 hours after formulation preparation. In another embodiment, the present invention comprises 64 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% about 6 hours after formulation preparation. In another embodiment, the present invention comprises 64 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% about 9 hours after formulation preparation. In another embodiment, the present invention comprises 64 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% about 12 hours after formulation preparation. In another embodiment, the present invention comprises 64 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% about 15 hours after formulation preparation. In another embodiment, the present invention comprises 64 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% about 18 hours after formulation preparation. In another embodiment, the present invention comprises 64 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% approximately 21 hours after formulation preparation. In another embodiment, the present invention comprises... 64 The radiochemical purity of the formulation of Cu and complexes of compounds of formula (I) or their salts is approximately 99% approximately 24 hours after formulation preparation.

[0069] According to the present invention, 67 Formulations of Cu and complexes of compound (I) can also maintain at least 90% radiochemical purity for at least 11 hours. This means that at least approximately 90% of the components present in the formulation remain intact after preparation. 67 The radioactive Cu isotope complexes with the compound of formula (I) or its salt for at least 11 hours. When present in the formulation... 67 When the radioactive Cu isotope is not complexed with the compound of formula (I) or its salt, 67 Radioactive Cu isotopes can be used as free... 67 Cu ions may exist as part of the radiodecomposition products.

[0070] In one embodiment, the present invention includes 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 90% at about 11 hours after formulation preparation. In another embodiment, the present invention comprises 67The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 91% at about 11 hours after formulation preparation. In another embodiment, the present invention comprises 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 92% at a time of about 11 hours after formulation preparation. In another embodiment, the present invention comprises 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 93% at a time of about 11 hours after formulation preparation. In another embodiment, the present invention comprises 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 94% at a time of about 11 hours after formulation preparation. In another embodiment, the present invention comprises 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 95% at a time of about 11 hours after formulation preparation. In another embodiment, the present invention comprises 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 96% at a time of about 11 hours after formulation preparation. In another embodiment, the present invention comprises 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 97% at a time of about 11 hours after formulation preparation. In another embodiment, the present invention comprises... 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 98% at about 11 hours after formulation preparation. In another embodiment, the present invention comprises 67 The radiochemical purity of the formulation of Cu and complexes of compounds of formula (I) or their salts was approximately 99% at approximately 11 hours after formulation preparation.

[0071] In one embodiment, the present invention includes 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is approximately 99% immediately after formulation preparation. In another embodiment, the present invention comprises... 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% about 1 hour after formulation preparation. In another embodiment, the present invention comprises 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% about 3 hours after formulation preparation. In another embodiment, the present invention comprises 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% about 6 hours after formulation preparation. In another embodiment, the present invention comprises67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% about 9 hours after formulation preparation. In another embodiment, the present invention comprises 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% about 12 hours after formulation preparation. In another embodiment, the present invention comprises 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% about 15 hours after formulation preparation. In another embodiment, the present invention comprises 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% about 18 hours after formulation preparation. In another embodiment, the present invention comprises 67 The radiochemical purity of the formulation of Cu and a complex of a compound of formula (I) or a salt thereof is about 99% approximately 21 hours after formulation preparation. In another embodiment, the present invention comprises... 67 The radiochemical purity of the formulation of Cu and complexes of compounds of formula (I) or their salts is approximately 99% approximately 24 hours after formulation preparation.

[0072] Preparation of the aqueous formulation of the present invention A compound of formula (I) or a salt thereof, complexed with Cu ions, can be provided by mixing the compound of formula (I) or a salt thereof with a solution of Cu ions in the presence of a buffer solution. The solution can then be filtered and subsequently washed to provide a formulation comprising a compound of formula (I) or a salt thereof complexed with Cu ions. Therefore, the present invention provides a method for preparing an aqueous formulation comprising a compound of formula (I) complexed with Cu ions, the method comprising the following steps: i) Prepare a buffer solution of acetate, wherein the buffer solution further comprises ethanol and gentianic acid or a salt thereof; ii) Dissolve the compound of formula (I) or a salt thereof in the buffer solution obtained in step i); iii) Add the Cu ion solution to the solution obtained in step ii); iv) Filter the solution obtained in step iii) onto the stationary phase; and v) Wash the stationary phase from step iv) with ethanol and brine; To recover aqueous formulations containing compounds of formula (I) or their salts that are complexed with Cu ions.

[0073] The buffer solution can be an ammonium acetate solution. Alternatively, the buffer solution can be a sodium acetate solution. The use of an acetate buffer solution is to maintain the pH within the range that allows for maximum and rapid complexation of the compound of formula (I) or its salt with Cu ions. The buffer solution can contain an aqueous solution of ammonium acetate at a concentration of about 0.08 to about 0.12 mol / L. In one embodiment, the buffer solution contains an aqueous solution of ammonium acetate at a concentration of about 0.08 mol / L. In another embodiment, the buffer solution contains an aqueous solution of ammonium acetate at a concentration of about 0.09 mol / L. In another embodiment, the buffer solution contains an aqueous solution of ammonium acetate at a concentration of about 0.1 mol / L. In another embodiment, the buffer solution contains an aqueous solution of ammonium acetate at a concentration of about 0.11 mol / L. In another embodiment, the buffer solution contains an aqueous solution of ammonium acetate at a concentration of about 0.12 mol / L. In a preferred embodiment, the buffer solution contains a 0.1 mol / L aqueous solution.

[0074] The buffer solution also contains ethanol as a component. As described above, the ethanol may be anhydrous or may have undergone a drying process known in the art beforehand. The buffer solution may contain ethanol at a concentration of about 3% to about 11% (v / v). In one embodiment, the buffer solution contains ethanol at a concentration of about 3% (v / v). In another embodiment, the buffer solution contains ethanol at a concentration of about 3.5% (v / v). In another embodiment, the buffer solution contains ethanol at a concentration of about 4% (v / v). In another embodiment, the buffer solution contains ethanol at a concentration of about 4.5% (v / v). In another embodiment, the buffer solution contains ethanol at a concentration of about 5% (v / v). In another embodiment, the buffer solution contains ethanol at a concentration of about 6% (v / v). In another embodiment, the buffer solution contains ethanol at a concentration of about 7% (v / v). In another embodiment, the buffer solution contains ethanol at a concentration of about 8% (v / v). In another embodiment, the buffer solution contains ethanol at a concentration of about 9% (v / v). In another embodiment, the buffer solution contains ethanol at a concentration of about 10% (v / v). In another embodiment, the buffer solution contains ethanol at a concentration of about 10% (v / v). In another embodiment, the buffer solution contains ethanol at a concentration of about 11% (v / v). In a preferred embodiment, the buffer solution contains ethanol at a concentration of about 10% (v / v).

[0075] The buffer solution also contains gentianic acid or a salt thereof as a component. As described above, salts of gentianic acid may include sodium salts or sodium salt hydrates. Other salts of gentianic acid are also considered. The buffer solution may contain sodium gentianate at a concentration of about 0.1% to about 0.55% (w / v). In one embodiment, the buffer solution contains sodium gentianate at a concentration of about 0.1% (w / v). In another embodiment, the buffer solution contains sodium gentianate at a concentration of about 0.15% (w / v). In another embodiment, the buffer solution contains sodium gentianate at a concentration of about 0.2% (w / v). In another embodiment, the buffer solution contains sodium gentianate at a concentration of about 0.25% (w / v). In another embodiment, the buffer solution contains sodium gentianate at a concentration of about 0.25% (w / v). In another embodiment, the buffer solution contains sodium gentianate at a concentration of about 0.3% (w / v). In another embodiment, the buffer solution contains sodium gentianate at a concentration of about 0.35% (w / v). In another embodiment, the buffer solution contains sodium gentianate at a concentration of about 0.4% (w / v). In another embodiment, the buffer solution contains sodium gentiolate at a concentration of about 0.45% (w / v). In another embodiment, the buffer solution contains sodium gentiolate at a concentration of about 0.5% (w / v). In yet another embodiment, the buffer solution contains sodium gentiolate at a concentration of about 0.55% (w / v). In a preferred embodiment, the buffer solution contains sodium gentiolate at a concentration of about 0.228% (w / v).

[0076] According to one embodiment of the invention, a buffer solution can be prepared by mixing ethanol and gentian acid or a salt thereof with an aqueous solution of ammonium acetate. The buffer solution can be prepared by sequentially adding ethanol and gentian acid or a salt thereof to the aqueous solution of ammonium acetate, or alternatively, by adding ethanol and gentian acid or a salt thereof together to the ammonium acetate solution. In one embodiment of the invention, the buffer solution comprises ammonium acetate at a concentration of about 0.1 M, ethanol at a concentration of about 4-11% (v / v), and gentian acid or a salt thereof at a concentration of about 0.5% (w / v).

[0077] According to one embodiment of the invention, a compound of formula (I) or a salt thereof is mixed with an aqueous buffer solution of ammonium acetate containing ethanol and gentic acid or a salt thereof. The compound of formula (I) or a salt thereof may be obtained as a solid. In one embodiment, the compound of formula (I) or a salt thereof is obtained as a lyophilized powder. In one embodiment, the compound of formula (I) or a salt thereof obtained as a lyophilized powder is mixed with an aqueous buffer solution of ammonium acetate containing ethanol and gentic acid or a salt thereof. In one embodiment, about 15 μg to about 65 μg of the lyophilized powder of the compound of formula (I) or a salt thereof is mixed with an aqueous buffer solution of ammonium acetate containing ethanol and gentic acid or a salt thereof. In another embodiment, about 15 μg of the lyophilized powder of the compound of formula (I) or a salt thereof is mixed with an aqueous buffer solution of ammonium acetate containing ethanol and gentic acid or a salt thereof. In another embodiment, about 20 μg of the lyophilized powder of the compound of formula (I) or a salt thereof is mixed with an aqueous buffer solution of ammonium acetate containing ethanol and gentic acid or a salt thereof. In another embodiment, about 25 μg of the compound of formula (I) or a salt thereof as a lyophilized powder is mixed with an ammonium acetate aqueous buffer solution containing ethanol and gentic acid or a salt thereof. In another embodiment, about 30 μg of the compound of formula (I) or a salt thereof as a lyophilized powder is mixed with an ammonium acetate aqueous buffer solution containing ethanol and gentic acid or a salt thereof. In another embodiment, about 35 μg of the compound of formula (I) or a salt thereof as a lyophilized powder is mixed with an ammonium acetate aqueous buffer solution containing ethanol and gentic acid or a salt thereof. In another embodiment, about 40 μg of the compound of formula (I) or a salt thereof as a lyophilized powder is mixed with an ammonium acetate aqueous buffer solution containing ethanol and gentic acid or a salt thereof. In another embodiment, about 45 μg of the compound of formula (I) or a salt thereof as a lyophilized powder is mixed with an ammonium acetate aqueous buffer solution containing ethanol and gentic acid or a salt thereof. In another embodiment, about 50 μg of the compound of formula (I) or a salt thereof as a lyophilized powder is mixed with an ammonium acetate aqueous buffer solution containing ethanol and gentic acid or a salt thereof. In another embodiment, about 55 μg of the compound of formula (I) or a salt thereof as a lyophilized powder is mixed with an ammonium acetate aqueous buffer solution containing ethanol and gentic acid or a salt thereof. In another embodiment, about 60 μg of the compound of formula (I) or a salt thereof as a lyophilized powder is mixed with an ammonium acetate aqueous buffer solution containing ethanol and gentic acid or a salt thereof. In another embodiment, about 65 μg of the compound of formula (I) or a salt thereof as a lyophilized powder is mixed with an ammonium acetate aqueous buffer solution containing ethanol and gentic acid or a salt thereof.

[0078] A solution of Cu ions is added to a mixture of a compound of formula (I) or a salt thereof with an aqueous buffer solution of ammonium acetate containing ethanol and gentian acid or a salt thereof, and allowed to stand for a period of time.

[0079] In one embodiment, the Cu ion solution is a solution of a Cu salt. In another embodiment, the Cu ion solution is a solution of a copper chloride salt. In yet another embodiment, the Cu ion solution is a solution of a copper(II) chloride salt. In yet another embodiment, the Cu ion solution contains... 60 A solution of a copper salt of a radioactive Cu isotope. In another embodiment, the solution of Cu ions is a solution containing... 61 A solution of a chloride salt of a radioactive Cu isotope. In another embodiment, the solution of Cu ions is a solution containing... 64 A solution of a chloride salt of a radioactive Cu isotope. In another embodiment, the solution of Cu ions is a solution containing... 67 A solution of a chloride salt of a radioactive Cu isotope. In another embodiment, the Cu ion solution is a solution of a radioactive copper(II) chloride salt. In another embodiment, the Cu ion solution is a solution of a copper(II) chloride salt, wherein the copper is... 61 Cu isotopes. In another embodiment, the Cu ion solution is a solution of copper(II) chloride salt, wherein the copper is... 64 Cu isotopes. In another embodiment, the Cu ion solution is a solution of copper(II) chloride salt, wherein the copper is... 67 Cu isotopes. In another embodiment, the solution of Cu ions is [ 61 A solution of CuCl2. In another embodiment, the solution of Cu ions is […]. 64 A solution of CuCl2. In another embodiment, the solution of Cu ions is […]. 67 Cu]CuCl2 solution.

[0080] The Cu ion solution is provided as an aqueous solution. Cu ions can be provided in an aqueous hydrochloric acid solution. In one embodiment, Cu ions are provided in a hydrochloric acid solution of about 0.01 to about 0.1 mol / L. In another embodiment, Cu ions are provided in a hydrochloric acid solution of about 0.01 mol / L. In another embodiment, Cu ions are provided in a hydrochloric acid solution of about 0.02 mol / L. In another embodiment, Cu ions are provided in a hydrochloric acid solution of about 0.05 mol / L. In another embodiment, Cu ions are provided in a hydrochloric acid solution of about 0.075 mol / L. In another embodiment, Cu ions are provided in a hydrochloric acid solution of about 0.1 mol / L. In a preferred embodiment, Cu ions are provided in a hydrochloric acid solution of about 0.05 mol / L. 64 Cu ions are provided in the form of CuCl2. In another preferred embodiment, Cu ions are provided in a solution of approximately 0.05 mol / L hydrochloric acid. 67 Cu ions are provided in the form of CuCl2.

[0081] 64 A solution of the Cu-radioactive isotope is provided as an aqueous solution, with a radioactivity of approximately 750 to approximately 3500 MBq. In one embodiment, 64 The radioactivity of the Cu-radioisotope solution is approximately 750 MBq. In another embodiment, 64 The radioactivity of the Cu-radioisotope solution is approximately 1000 MBq. In another embodiment, 64 The radioactivity of the Cu-radioisotope solution is approximately 1250 MBq. In another embodiment, 64 The radioactivity of the Cu-radioisotope solution is approximately 1500 MBq. In another embodiment, 64 The radioactivity of the Cu-radioisotope solution is approximately 1750 MBq. In another embodiment, 64 The radioactivity of the Cu-radioisotope solution is approximately 2000 MBq. In another embodiment, 64 The radioactivity of the Cu-radioisotope solution is approximately 2250 MBq. In another embodiment, 64 The radioactivity of the Cu-radioisotope solution is approximately 2500 MBq. In another embodiment, 64 The radioactivity of the Cu-radioisotope solution is approximately 2750 MBq. In another embodiment, 64 The radioactivity of the Cu-radioisotope solution is approximately 3000 MBq. In another embodiment, 64 The radioactivity of the Cu-radioisotope solution is approximately 3250 MBq. In another embodiment, 64 The radioactivity of the Cu-radioisotope is approximately 3500 MBq.

[0082] 67 A solution of the Cu-radioactive isotope is provided as an aqueous solution, with a radioactivity of approximately 1000 to approximately 5000 MBq. In one embodiment, 67 The radioactivity of the Cu-radioisotope is approximately 1000 MBq. In another embodiment, 67 The radioactivity of the Cu-radioisotope is approximately 1500 MBq. In another embodiment, 67 The radioactivity of the Cu-radioisotope is approximately 2000 MBq. In another embodiment, 67 The radioactivity of the Cu-radioisotope is approximately 2500 MBq. In another embodiment, 67 The radioactivity of the Cu-radioisotope is approximately 3000 MBq. In another embodiment, 67The radioactivity of the Cu-radioisotope is approximately 3500 MBq. In another embodiment, 67 The radioactivity of the Cu-radioisotope is approximately 4000 MBq. In another embodiment, 67 The radioactivity of the Cu-radioisotope is approximately 4500 MBq. In another embodiment, 67 The radioactivity of the Cu-radioisotope is approximately 5000 MBq.

[0083] A mixture of a Cu ion, a compound of Formula (I), or asalt thereof, and the buffering solution of aqueous ammonium acetate comprising ethanol and gentisic acid, or a salt thereof, can be allowed to stand at room temperature. The mixture can be allowed to stand with stirring, or alternatively, without stirring. The mixture can be allowed to stand for about 5 to about 25 minutes. In one embodiment, the mixture of Cu ions, a compound of Formula (I), or a salt thereof, and the aqueous ammonium acetate buffer solution comprising ethanol and gentisic acid is allowed to stand without stirring for about 5 minutes. In another embodiment, the mixture of Cu ions, a compound of Formula (I), or a salt thereof, and the aqueous ammonium acetate buffer solution comprising ethanol and gentisic acid is allowed to stand without stirring for about 10 minutes. In another embodiment, the mixture of Cu ions, the compound of formula (I) or a salt thereof, and an aqueous ammonium acetate buffer solution containing ethanol and gentianic acid is allowed to stand without stirring for about 15 minutes. In another embodiment, the mixture of Cu ions, the compound of formula (I) or a salt thereof, and an aqueous ammonium acetate buffer solution containing ethanol and gentianic acid is allowed to stand without stirring for about 20 minutes. In another embodiment, the mixture of Cu ions, the compound of formula (I) or a salt thereof, and an aqueous ammonium acetate buffer solution containing ethanol and gentianic acid is allowed to stand without stirring for about 25 minutes. In a preferred embodiment, the mixture of Cu ions, the compound of formula (I) or a salt thereof, and an aqueous ammonium acetate buffer solution containing ethanol and gentianic acid is allowed to stand without stirring for about 15 minutes. In another preferred embodiment, the mixture of Cu ions, the compound of formula (I) or a salt thereof, and an aqueous ammonium acetate buffer solution containing ethanol and gentianic acid is allowed to stand without stirring for about 15 minutes. 64 The mixture of Cu-radioactive isotope, compound of formula (I) or its salt and ammonium acetate aqueous buffer solution containing ethanol and gentianic acid is left to stand for about 20 minutes without stirring.

[0084] According to another embodiment of the invention, a mixture of Cu ions, a compound of formula (I) or a salt thereof, and an aqueous buffer solution of ammonium acetate containing ethanol and gentianic acid or a salt thereof is filtered. The mixture may be filtered to remove any acetate that may remain in the solution. The mixture may be filtered by a solid-phase extraction method. The mixture may be filtered by a solid-phase extraction method in which the stationary phase of the solid-phase extraction column retains the compound of formula (I) or a salt thereof complexed with Cu ions, any uncomplexed compound of formula (I) or a salt thereof, and some gentianic acid present in salt form, such as sodium gentianate. As used herein, the term "stationary phase" refers to a resinous material that is held within the solid-phase extraction column and allows separation of compounds based on their polarity.

[0085] The solid-phase extraction method described herein can use a reversed-phase stationary phase. As used herein, the term "reverse-phase" in relation to the stationary phase refers to a stationary phase that is inherently hydrophobic and therefore has an affinity for hydrophobic or uncharged molecules. Examples of reversed-phase stationary phases may include Phenomenex Strata-X 33u polymer reversed-phase, Waters tC18, or Waters C18. Other similar stationary phases may be used. Because the solid-phase extraction method uses a reversed-phase stationary phase, ammonium acetate from the buffer solution, any free Cu ions, and most of the remaining gentianic acid or its salts are not retained by the stationary phase and are discarded.

[0086] In one embodiment, a mixture of Cu ions, compound (I), and an aqueous ammonium acetate buffer solution is filtered through a solid-phase extraction column. In another embodiment, the mixture of Cu ions, compound (I), and an aqueous ammonium acetate buffer solution is filtered through a solid-phase extraction column having a reversed-phase stationary phase. In one embodiment, ammonium acetate and gentianic acid from the buffer solution are removed by the solid-phase extraction column having a reversed-phase stationary phase. In one embodiment, the compound (I) complexed with Cu ions is retained by the solid-phase extraction column having a reversed-phase stationary phase. In a preferred embodiment, 64 A mixture of a Cu-radioactive isotope, a compound of formula (I), and an ammonium acetate aqueous buffer solution is filtered through a solid-phase extraction column with a reversed stationary phase. In a preferred embodiment, with 64 The Cu ion-complexed compound of formula (I) is retained by a solid-phase extraction column having a reversed stationary phase. In another preferred embodiment, the Cu ion-complexed compound of formula (I) is retained by a solid-phase extraction column having a reversed stationary phase. 67 A mixture of a Cu-radioactive isotope, a compound of formula (I), and an aqueous ammonium acetate buffer solution is filtered through a solid-phase extraction column with a reversed stationary phase. In another preferred embodiment, with 67 The Cu ion-complexed compound of formula (I) was retained by a solid-phase extraction column with a reversed stationary phase.

[0087] The compound of formula (I) complexed with Cu ions is eluted from a solid-phase extraction column containing a stationary phase by washing with a solvent. Since the solid-phase extraction column contains a reversed stationary phase, elution of the compound of formula (I) complexed with Cu ions requires washing the stationary phase with ethanol, brine, and / or another solvent. In one embodiment, the solid-phase extraction column is washed with ethanol to elute the compound of formula (I) complexed with Cu ions. In another embodiment, the solid-phase extraction column is washed with brine to elute the compound of formula (I) complexed with Cu ions. In yet another embodiment, the solid-phase extraction column is washed with both ethanol and brine to elute the compound of formula (I) complexed with Cu ions. In a preferred embodiment, the solid-phase extraction column is washed sequentially with ethanol and brine to elute the compound of formula (I) complexed with Cu ions. In a preferred embodiment, the solid-phase extraction column is washed sequentially with ethanol and brine to provide the formulation of the present invention. In a preferred embodiment, the solid-phase extraction column is washed sequentially with ethanol and brine to elute the compound of formula (I) complexed with Cu ions and any retained components, such as gentianic acid or its salts.

[0088] As described above, the inventors have discovered that formulations of formula (I) further comprising L-methionine and complexed with Cu ions exhibit greater stability against radiodegradation. In another preferred embodiment, the solid-phase extraction column is washed sequentially with ethanol and brine to elute the Cu-complexed compound of formula (I) and gentic acid or a salt thereof into an aqueous solution of L-methionine. In another preferred embodiment, the solid-phase extraction column is washed sequentially with ethanol and brine to elute the Cu-complexed compound of formula (I), ammonium acetate, and gentic acid or a salt thereof into an aqueous solution of L-methionine. In another preferred embodiment, the concentration of L-methionine in the brine solution (to which the solid-phase extraction column is washed) is about 2.5 mg / mL. In another preferred embodiment, the solid-phase extraction column is washed sequentially with ethanol and brine to provide the formulation of the present invention.

[0089] Those skilled in the art will understand that the excipients of the formulation include solvents for eluting compounds of formula (I) complexed with Cu ions from the stationary phase, and that the amount of each solvent is related to the amount of each excipient in the formulation of the present invention.

[0090] Those skilled in the art will understand that this disclosure provides a manual process for preparing formulations according to the invention. Those skilled in the art will also understand that the steps described herein can be automated by using a suitable automated radiosynthesis module to obtain formulations according to the invention.

[0091] The inventors have discovered that, given the higher initial radioactivity, the formulations disclosed herein exhibit greater stability and show reduced radiodecomposition. This enhanced stability can be attributed to the increased radiochemical purity of the formulation at the specified radioactivity level. 64 The stability of the Cu-SARTATE formulation can be observed up to 45 hours after preparation. 67 The formulations of Cu-SARTATE exhibit stability up to 11 hours after preparation. When the formulations of this invention are used for treatment or therapeutic purposes, greater stability may mean that doses for multiple patients at multiple remote locations can be prepared simultaneously at a single facility. This may mean that manufacturing resources are required only at a single facility rather than multiple facilities, and higher formulation production efficiency can be achieved. Further advantages can be provided when the formulations of this invention are used for imaging purposes, as clinical imaging sites can accept injectable dosage forms. This can be particularly advantageous for clinical sites where dedicated radiopharmaceutical manufacturing facilities are not available.

[0092] The formulations of the present invention comprise a ligand-radioisotope complex, wherein the ligand is a compound of formula (I) or a salt thereof. The compound of formula (I) or a salt thereof and the radioisotope may be provided in separate containers. Alternatively, the compound of formula (I) or a salt thereof and the radioisotope may be provided together as a ligand-radioisotope complex.

[0093] Containers consisting of compounds of formula (I) or salts thereof can be provided as lyophilized powders of compounds of formula (I) or salts thereof. Containers can be provided at temperatures ranging from -20°C to 20°C.

[0094] The formulation shown can be provided as a kit comprising a container for the radioisotope and separate containers for the ligand, as well as instructions for preparing the aqueous formulation of the present invention. In one embodiment, the kit of the present invention comprises providing... 64 A container for a solution of the radioactive isotope Cu and a separate container for providing a compound of formula (I) or a salt thereof. The container for providing the radioactive isotope may contain a solution of a metal salt, wherein the metal is a radioactive nuclide.

[0095] In one embodiment, the kit of the present invention comprises having 64 A container for a solution of a Cu radioactive isotope. In a further embodiment, the kit of the present invention comprises a container containing a solution of a copper salt, the copper salt containing... 64 Cu radioactive isotope. In another embodiment, the kit of the present invention comprises a container having a solution of a chloride salt containing... 64Cu is a radioactive isotope. In another embodiment, the kit of the present invention comprises a container containing a solution of a radioactive copper(II) chloride salt. In another embodiment, the kit of the present invention comprises a container containing a solution of a copper(II) chloride salt, wherein copper ions are... 64 Cu isotopes. In another embodiment, the kit of the present invention comprises having [ 64 Container for CuCl2 solution.

[0096] In one embodiment, the kit of the present invention comprises having 67 A container for a solution of a Cu radioactive isotope. In another embodiment, the kit of the present invention comprises a container containing a solution of a copper salt, said copper salt containing 67 Cu radioactive isotope. In another embodiment, the kit of the present invention comprises a container having a solution of a chloride salt containing... 67 Cu is a radioactive isotope. In another embodiment, the kit of the present invention comprises a container containing a solution of a radioactive copper(II) chloride salt. In another embodiment, the kit of the present invention comprises a container containing a solution of a copper(II) chloride salt, wherein copper ions are... 67 Cu isotopes. In another embodiment, the kit of the present invention comprises having [ 67 Container for CuCl2 solution.

[0097] Solutions of radioactive isotopes are typically provided as aqueous solutions. In one embodiment, the kit of the present invention provides radioactive isotopes in aqueous solution form. In a further embodiment, the kit of the present invention provides radioactive isotopes in acidic aqueous solution form. In another embodiment, the kit of the present invention provides radioactive isotopes as hydrochloric acid solutions. Radioactive isotopes can be provided as hydrochloric acid solutions with a concentration of about 0.01 to about 0.1 mol / L.

[0098] In one embodiment, the kit of the present invention comprises having [ 64 A container for a hydrochloric acid solution of Cu[CuCl2]. In one embodiment, the kit of the present invention comprises having […]. 64 A container for a hydrochloric acid solution of CuCl2, wherein the concentration of the hydrochloric acid is about 0.02 mol / L. In one embodiment, the kit of the present invention comprises [ 64 A container for a hydrochloric acid solution of CuCl2, wherein the concentration of the hydrochloric acid is about 0.05 mol / L. In one embodiment, the kit of the present invention comprises […]. 64 A container for a hydrochloric acid solution of CuCl2, wherein the concentration of the hydrochloric acid is about 0.1 mol / L.

[0099] In one embodiment, the kit of the present invention comprises having [ 67 A container for a hydrochloric acid solution of CuCl2. In another embodiment, the kit of the present invention comprises […]. 67 A container for a hydrochloric acid solution of CuCl2, wherein the concentration of the hydrochloric acid is about 0.02 mol / L. In another embodiment, the kit of the present invention comprises […]. 67 A container for a hydrochloric acid solution of CuCl2, wherein the concentration of the hydrochloric acid is about 0.05 mol / L. In another embodiment, the kit of the present invention comprises […]. 67 A container for a hydrochloric acid solution of CuCl2, wherein the concentration of the hydrochloric acid is about 0.1 mol / L.

[0100] The kit may further comprise a container consisting of ethanol, sodium chloride, and gentic acid in a buffer solution. The container may be provided as ethanol, sodium chloride, and gentic acid in an aqueous solution, or alternatively, the container may consist only of ethanol, sodium chloride, and gentic acid. In one embodiment, the kit comprises a container consisting of ethanol, sodium chloride, and gentic acid or a salt thereof in an ammonium acetate buffer solution.

[0101] The kit may also include a container consisting of ethanol, sodium chloride, gentic acid or a salt thereof, and L-methionine or a salt thereof in a buffer solution. The container of the kit may be provided as ethanol, sodium chloride, gentic acid or a salt thereof, and L-methionine or a salt thereof in an aqueous solution, or alternatively, the container may consist only of ethanol, sodium chloride, gentic acid or a salt thereof, and L-methionine or a salt thereof. In one embodiment, the kit includes a container consisting of ethanol, sodium chloride, gentic acid or a salt thereof, and L-methionine or a salt thereof. In another embodiment, the kit includes a container consisting of ethanol, sodium chloride, gentic acid or a salt thereof, and L-methionine or a salt thereof in an ammonium acetate buffer solution.

[0102] Uses of the formulation of the present invention The formulations of this invention can be used specifically for medical diagnostic and therapeutic purposes. Complexes having ligands carrying suitable target fragments can be used to target specific tissue types. For such complexes deemed suitable for in vivo diagnostic and therapeutic purposes, in addition to the required solubility and stability properties in solution, the complexes must also exhibit suitable kinetic, stability, and clearance properties under physiological conditions. As used herein, the term "complex" can refer to ligand-metal ion complexes, wherein the metal ion is a radioactive isotope, or alternatively, the metal ion is a non-radioactive isotope.

[0103] Therefore, the present invention provides a method for radiographic imaging, a method for diagnosing a disease in a subject, or a method for treating a disease in a subject, comprising administering to the subject an effective amount of a formulation as defined herein. The inventors have discovered that the formulation of the present invention can be used in methods of radiographic imaging, diagnostic methods, or methods of treating cancer.

[0104] As used herein, the term "cancer" broadly encompasses a class of neoplastic diseases characterized by abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread to other parts of the body, and therefore, as defined herein, include all malignant (cancerous) disease states. Thus, the term covers the treatment of tumors.

[0105] Therefore, the term "tumor" is generally used to define any malignant cancer or precancerous cell growth and may include leukemia, but is specifically for solid tumors or cancers such as melanoma, colon cancer, lung cancer, ovarian cancer, skin cancer, breast cancer, pancreatic cancer, pharyngeal cancer, brain cancer, prostate cancer, CNS cancer, and kidney cancer (as well as other cancers).

[0106] Somatostatin receptors, particularly SSTR2, are also highly expressed in the plasma membrane of certain tumors and cancers, including pancreatic, gastrointestinal, and pulmonary neuroendocrine tumors (NETs), pituitary adenomas, breast cancer, meningiomas, neuroblastomas, medulloblastomas, pheochromocytomas, and paragangliomas. The presence of somatostatin receptors on these tumors has led to the development and clinical application of stable somatostatin receptors, such as compounds with octreotide nucleotide motifs. The inventors have discovered that the complexes of compounds of formula (I) and Cu ions found in the formulations of this invention have shown particular efficacy in binding to somatostatin receptors, particularly subtypes 2 and 5. In some embodiments, the formulations can be used for radiographic imaging, diagnosis, or treatment of cancers expressing or highly expressing somatostatin receptors.

[0107] The formulations of this invention comprise compounds of formula (I) containing an octreotide acid motif, which are similar to octreotide (a clinically used somatostatin analog). Somatostatin is released by neuroendocrine cells of the gastrointestinal tract and exerts its effects through five somatostatin receptor subtypes (SSTR1 to 5). Given the similarity between the octreotide acid motif and octreotide, compounds of formula (I) can be located and bound to specific sites where somatostatin receptors are present. Similarly, compounds of formula (I) complexed with Cu ions can also be located and bound to the same sites.

[0108] The radioisotope-ligand complex of the present invention may contain a radioisotope, such as...64 Cu. 64 Cu isotopes have a half-life of approximately 12.7 hours and decay through positron emission and beta decay, which makes... 64 Cu-labeled complexes are suitable for various radiographic imaging modalities. In particular, 64 The decay properties and half-life of Cu make this radioactive isotope a favorable choice for positron emission tomography (PET) and single-photon emission computed tomography (SPECT). The radioactive isotope-ligand complexes of the present invention may contain radioactive isotopes, such as… 61 Cu. 61 Cu isotopes have a half-life of about 3 hours and decay through positron emission, which makes... 61 Cu-labeled complexes are suitable for various radiographic imaging modalities. The radioisotope-ligand complexes of this invention may contain radioisotopes, such as… 67 Cu. 67 Cu isotopes have a half-life of approximately 61.8 hours and decay through β-emission, which makes... 67 Cu-labeled complexes are suitable for SPECT imaging. 67 Cu-labeled complexes can also be used in radiotherapy.

[0109] Effective amounts of compound (I) and Cu radioisotope (e.g.) 60 Cu、 61 Cu、 64 Cu or 67 Administration of a formulation containing a Cu ion can lead to the binding of a complex of the compound of formula (I) and the Cu radioisotope to a somatostatin receptor. When the somatostatin receptor is expressed on the surface of a tumor, the complex of the compound of formula (I) and Cu ions can bind to the somatostatin receptor. In one embodiment, the present invention provides a method for radiographic imaging comprising administering to a subject a formulation containing a compound of formula (I) and Cu ions. In one embodiment, the compound of formula (I) and Cu ions... 64 Cu or 67Preparations containing Cu ions can be used in radiographic imaging methods. For example, monitoring subjects administered a preparation containing a compound of formula (I) and a Cu radioisotope via PET or SPECT allows for visualization and subsequent detection of tumor sites. The visualization information obtained through radiographic imaging can provide information relating to the location of any such tumor site. For example, monitoring subjects administered a radiolabeled complex via SPECT allows for visualization and subsequent detection of tumor sites. This provides information relating to the location of the tumor. Repeat imaging at later time points allows for monitoring of the clearance of the radioisotope-ligand complex, which enables the calculation of dosimetry estimates. Those skilled in the art will understand that the amount administered to aid in radiographic imaging can vary and will subsequently depend on the nature of the subject and the intended imaging site.

[0110] For a complex to be suitable for radiographic imaging purposes, the radioisotope-ligand complex must exhibit sufficient metabolic stability, i.e., the time required for the complex to remain intact and for the radioisotope to remain bound to the ligand. This invention provides a compound of formula (I) and... 64 The Cu complex, as demonstrated by the absence of radioactive isotope loss and metabolic degradation, remained intact for up to 45 hours.

[0111] For radiographic imaging, diagnostic, or therapeutic purposes, the formulations of the present invention can be administered to a subject. Administration is preferably via parenteral route, or intravenous injection. Alternatively, the formulations of the present invention can be administered via intra-arterial or other routes for delivery into the systemic circulation. The subject who has been administered the formulation is then placed in a PET scanner to obtain images showing the localization of the radioisotope-ligand complex, and subsequently, the location of any tumors. Tumors can then be diagnosed and detected. Alternatively, radiographic images can be obtained by analyzing samples (e.g., blood or tissue samples) that have been exposed to the formulations of the present invention using gamma spectroscopy, gamma counting, liquid scintillation counting, autoradiography, or beta probe analysis.

[0112] In one embodiment, the present invention provides the use of an formulation comprising a compound of formula (I) in a method for radiographic imaging of a tumor or cancer. Those skilled in the art will understand that information obtained from radiographic imaging of a subject can be used to diagnose a tumor or cancer in the subject. In one embodiment, the present invention provides a method for diagnosing a tumor or cancer. In a further embodiment, the tumor or cancer may be a tumor or cancer expressing a somatostatin receptor. In one embodiment, the tumor or cancer is a neuroendocrine tumor. In another embodiment, the tumor or cancer is a pituitary adenoma. In another embodiment, the tumor or cancer is a neuroblastoma. In another embodiment, the tumor or cancer is a meningioma. In another embodiment, the tumor or cancer is a medulloblastoma. In another embodiment, the tumor or cancer is a breast cancer. In another embodiment, the tumor or cancer is a pheochromocytoma. In another embodiment, the tumor or cancer is a paraganglioma. In another embodiment, the tumor is a pancreatic tumor. In another embodiment, the tumor is a gastrointestinal tumor.

[0113] When the formulation of the present invention comprises a compound of formula (I) and a Cu radioisotope, application of the formulation can treat tumors or cancer. As described above, the compound of formula (I) can bind to somatostatin receptors on the surface of a tumor or cancer site, such that the binding of the compound to a site having a somatostatin receptor also results in the Cu radioisotope being adjacent to that site. The Cu radioisotope undergoes radioactive decay, the decay mode depending on the specific radioisotope selected, and because the tumor or cancer is close to the compound of formula (I) and the Cu radioisotope, the decay products can be used to treat tumors or cancer.

[0114] In one embodiment, the present invention provides the use of an formulation comprising a compound of formula (I) and a Cu radioisotope in a method for treating a tumor or cancer. In one embodiment, the tumor or cancer is a neuroendocrine tumor. In another embodiment, the tumor or cancer is a pituitary adenoma. In another embodiment, the tumor or cancer is a neuroblastoma. In another embodiment, the tumor or cancer is a meningioma. In another embodiment, the tumor or cancer is a medulloblastoma. In another embodiment, the tumor or cancer is a breast cancer. In another embodiment, the tumor or cancer is a pheochromocytoma. In another embodiment, the tumor or cancer is a paraganglioma. In another embodiment, the tumor is a pancreatic tumor. In another embodiment, the tumor is a gastrointestinal tumor.

[0115] References to any prior publications (or information derived therefrom) or any known matters in this specification are not, and should not be construed as, an admission or endorsement or any form of advice: prior publications (or information derived therefrom) or known matters constitute part of the general knowledge in the field of effort covered by this specification.

[0116] Throughout the specification and the accompanying claims, unless the context otherwise requires, the word “comprise” and variations such as “comprises” and “comprising” shall be understood to imply inclusion of the said integer or step or group of integers or steps, but not to exclude any other integer or step or group of integers or steps.

[0117] Example Example 1 - Low dose of radiodegradation with ethanol and sodium gentianate incorporated as excipients. 64 Preparation of Cu-SARTATE formulations Prepare a 0.1 M ammonium acetate buffer solution, wherein the buffer solution also contains 4-10% (v / v) ethanol. The buffer solution also contains sodium gentiolate, wherein 5 mL of the buffer solution contains 38 mg of sodium gentiolate.

[0118] Compound (I) was obtained as a lyophilized powder. 20 μg of the lyophilized form of compound (I) was dissolved in 5 mL of the prepared buffer solution.

[0119] preparation[ 64 A solution of CuCl2 in 0.05 M hydrochloric acid, wherein a 300 μL volume of this solution contains 1500 MBq of [CuCl2]. 64 Cu]. 300 μL of this [ 64 CuCl2 solution was added to a solution containing compound (I) and sodium gentianate in ammonium acetate buffer. The combined solution was then allowed to stand at room temperature for 15 minutes without stirring.

[0120] The solution was then filtered through a solid-phase extraction column. The column was then eluted with 1.0 mL of ethanol followed by 9.0 mL of saline solution into a sterile product vial to obtain a 10 mL volume. 64 Cu-SARTATE ethanol / salt aqueous solution. HPLC analysis of the resulting solution can be found in [reference needed]. Figure 1 The results showed a radiochemical purity exceeding 97%. Further HPLC analysis of the same product solution at multiple time points was observed. Figure 2 The results showed that the radiochemical purity remained >90% for more than 11 hours.

[0121] Example 2 - Ethanol, sodium gentioate, and L-methionine were incorporated as excipients to reduce the high dose of radiodecomposition. 64 Preparation of Cu-SARTATE formulations Prepare a 0.1 M ammonium acetate buffer solution, wherein the buffer solution also contains 4-10% (v / v) ethanol. The buffer solution also contains sodium gentioate, wherein 5 mL of the buffer solution contains 114 mg of sodium gentioate.

[0122] Compound (I) was obtained as a lyophilized powder. 20 μg of the lyophilized form of compound (I) was dissolved in 5 mL of the prepared buffer solution.

[0123] preparation[ 64 A solution of CuCl2 in 0.05 M hydrochloric acid, wherein a 300 μL volume of this solution contains 4650 MBq of [CuCl2]. 64 Cu]. 300 μL of this [ 64 CuCl2 solution was added to a solution containing compound (I) and sodium gentianate in ammonium acetate buffer. The combined solution was then allowed to stand at room temperature for 15 minutes without stirring.

[0124] The solution was then filtered through a solid-phase extraction column. The column was then eluted with 1.0 mL of ethanol followed by 16.0 mL of saline solution to obtain a 20 mL volume of... 64 Cu-SARTATE ethanol / salt aqueous solution. HPLC analysis of the resulting solution can be found in [reference needed]. Figure 3 The results showed a radiochemical purity exceeding 98%. Further HPLC analysis of the same product solution at multiple time points was observed. Figure 4 The results showed that the radiochemical purity remained >90% for more than 45 hours.

[0125] Example 3 - Ethanol, sodium gentianate, and L-methionine were incorporated as excipients to reduce radiodecomposition. 67 Preparation of Cu-SARTATE formulations Prepare a 0.1 M ammonium acetate buffer solution, wherein the buffer solution also contains 4-10% (v / v) ethanol. The buffer solution also contains sodium gentioate, wherein 5 mL of the buffer solution contains 114 mg of sodium gentioate.

[0126] Compound (I) was obtained as a lyophilized powder. 60 μg of the lyophilized form of compound (I) was dissolved in 5 mL of the prepared buffer solution.

[0127] preparation[ 67A solution of CuCl2 in 0.05 M hydrochloric acid, wherein a 300 μL volume of this solution contains 4650 MBq of [CuCl2]. 64 Cu]. 300 μL of this [ 67 CuCl2 solution was added to a solution containing compound (I) and sodium gentianate in ammonium acetate buffer. The combined solution was then allowed to stand at room temperature for 15 minutes without stirring.

[0128] The solution was then filtered through a solid-phase extraction column. The column was then eluted with 1.0 mL of ethanol followed by 16.0 mL of saline solution into a sterile vial containing L-methionine solution (50 mg in 3 mL saline solution) to obtain a 20 mL volume. 67 Cu-SARTATE ethanol / salt aqueous solution. HPLC analysis of the resulting solution can be found in [reference needed]. Figure 5 The results showed a radiochemical purity exceeding 98%. Further HPLC analysis of the same product solution at multiple time points was observed. Figure 6 The results showed that the radiochemical purity remained >90% for more than 11 hours.

[0129] Example 4 - 64 In vitro serum stability of Cu-SARTATE Incubation with fresh human serum 64 Cu-SARTATE (radiochemical purity > 99%) demonstrated high metabolic stability. The resulting [product / treatment]... 64 HPLC analysis of serum incubated with Cu-SARTATE can be seen in Figure 7 The results showed that at 3, 20, 23, 26, and 34 hours, >90% of the radioactivity in the non-protein-bound fraction remained chelated, representing intact radiopeptides, and indicated that no copper loss or significant metabolic degradation was detected over a period of up to 43 hours.

[0130] Example 5 - 64 In vitro internalization and cell surface binding of Cu-SARTATE Using A427-7 cells carrying somatostatin receptor 2 64 Cu-SARTATE internalization and cell surface binding studies. The total percentage of radioactive addition per mg of internalized protein (%AR / mg protein) increased over time, reaching 23.9 ± 0.7 at 120 minutes. Figure 8 Within 30 minutes, 40.2 ± 0.7% AR / mg protein bound to the cell surface. Figure 9The value decreased to 31.2 ± 1.2 at 60 minutes and to 35.2 ± 1.3 at 120 minutes. This was achieved by adding cold Tyr to the medium. 3 Octreotide partially inhibits receptor-mediated internalization and cell surface binding. In parental A427 cells... 64 Normalized uptake of Cu-SARTATE was significantly lower in A427-7 cells expressing SSTR2 than in other cells. 64 The normalized uptake of Cu-SARTATE demonstrated the significance of receptor-specific accumulation. Figure 10 ).

[0131] Example 6 - 64 Biodistribution of Cu-SARTATE use 64 The biodistribution of Cu-SARTATE was investigated in Balb / c nude mice carrying A427-7 tumors. Figure 11 ). 64 Cu-SARTATE exhibited effective blood clearance at 2 hours (0.4 ± 0.2% ID / g, where % ID / g is the percentage of the injected dose per gram of tissue) and further clearance at 24 hours (0.1 ± 0.02% ID / g). At 2 hours post-administration, liver (3.1 ± 1.3% ID / g) and kidney (35.2 ± 5.4% ID / g) showed significant effects. 64 Cu-SARTATE uptake is highest at 24 hours post-administration. 64 The renal uptake of Cu SARTATE decreased by 71% to 10.1 ± 3.5% ID / g, indicating that... 64 Cu-SARTATE's effective renal clearance. At 24 hours post-administration, 64 Cu-SARTATE uptake in the lungs and spleen (i.e., non-target organs) was 0.6 ± 0.3% ID / g and 0.8 ± 0.2% ID / g, respectively, while muscle accumulation at 24 hours was 0.1 ± 0.01% ID / g. Two hours after administration, 64 Cu-SARTATE showed tumor uptake of up to 31.2 ± 13.1% ID / g and remained up to 31.4 ± 14.0% ID / g at 24 hours. Co-administration of an overdose of Tyr that blocks the receptor... 3 -Octreptide acid (XS Y) 3 -TATE) is used at 2 hours 64 Cu-SARTATE significantly reduced tumor uptake by 81% to 5.9 ± 0.3% ID / g, while increasing uptake in non-target tissues, as shown in the kidneys, by 135% to 47.7 ± 6.3% ID / g.

[0132] Example 7 - 64 In vivo PET imaging of Cu-SARTATE Figure 12 Small animal PET images showing Balb / c mice carrying A427-7 tumors with or without Tyr3-octreotide blockade at 2 and 24 hours. 64 Two hours after Cu-SARTATE, tumors were clearly visible, with an average tumor-to-background ratio of 48. The tumor-to-background ratio remained constant at 45 at 24 hours, indicating the highly specific binding and stability of the complex. Co-administration of excessive Tyr... 3 Octreotide effectively blocked tumor uptake, with a tumor-to-background ratio of 3.1 at 2 hours and below the limit of quantitation at 24 hours. Blocking assays further demonstrated... 64 Cu-SARTATE exhibits specific and low-level nonspecific binding to SSTR2. Significant uptake by the kidneys and bladder was evident in all animals, suggesting that renal clearance is the primary excretory route. The tumor-to-kidney ratio was 1.6 at 2 hours and increased to 2.8 at 24 hours.

[0133] Example 8 - In vivo toxicology of SARTATE A single-dose preclinical toxicology study was conducted in Sprague Dawley rats to evaluate the potential toxicity of SARTATE when administered intravenously. Solutions of 1:1 SARTATE-copper complex (SCC) and unlabeled SARTATE ligand (SL) were tested. The study was conducted in accordance with OECD GLP guidelines.

[0134] The testitem was administered once in a single dose of 3 mL / kg to six groups of 10 rats (5 rats / sex) at three doses of 50, 250, and 1000 μg / kg. Two control groups of 10 rats (5 rats / sex) were also included, each receiving the same volume dose of the carrier (10% ethanol in 0.9% sodium chloride and 0.056% gentianic acid).

[0135] On day 2, rats from the four groups in the main study (one group treated with the carrier and three groups treated with 50, 250, and 1000 μg / kg of test substance) were sacrificed. The remaining four groups from the recovery study, consisting of 10 rats each (one group treated with the carrier and three groups treated with 50, 250, and 1000 μg / kg of test substance), were observed during a 14-day treatment-free period and sacrificed on day 15 to assess the reversibility of any toxicity.

[0136] The following parameters were evaluated: mortality rate, daily clinical observation, weekly body weight, weekly food consumption, hematology, biochemistry, urinalysis, organ weight, and gross autopsy on the day of euthanasia. Extensive histopathological examination was performed on all animals.

[0137] No treatment-related mortality was observed in either the vector or treatment groups during treatment and recovery. The test substance did not produce any treatment-related clinical abnormalities in any animal during the 2-day and 15-day experimental periods. Both the treatment and vector control groups showed comparable weight gain during the 2-day and 15-day experimental periods. Feed intake was similar in both the control and treatment groups during the 2-day and 15-day experimental periods. Hematological, blood biochemistry, and urinalysis analyses showed no effects related to the test substance. No gross abnormalities were identified during necropsy of all animals. In this study, there was no evidence of any test substance-related effects on organ weight or all tissues examined histopathologically.

[0138] Under the conditions studied, the test substance administered intravenously at doses of 50, 250, and 1000 μg / kg did not produce toxic effects in Sprague-Dawley rats. Therefore, the No Observed Adverse Effect level (NOAEL) was 1000 μg / kg (1 mg / kg).

[0139] The NOAEL of 1 mg / kg in rats corresponds to a human equivalent dose (HED) of 0.16 mg / kg, or a total dose of 11.2 mg in a patient weighing 70 kg. The maximum possible total dose in this clinical trial will be 0.02 mg (20 mcg) per patient. Therefore, the NOAEL represents a safety range of 50 times the maximum human dose of SARTATE. This is based on the activity (200 MBq) determined by administration to patients. 64 The dosage of Cu-SARTATE is such that the expected actual dose of SARTATE injected will be a portion of the total possible dose, which greatly increases the safety margin.

[0140] Example 9 - In vitro genotoxicity of SARTATE To evaluate the mutagenic potential of SARTATE, a GLP AMES test was performed on solutions of SARTATE-copper-complex (SCC) and unlabeled SARTATE ligand (SL) in a 1:1 ratio. The SL:SCC solution did not induce an appropriate fold increase in the mean revertant mutant per plate relative to the mean revertant mutant per plate from the appropriate vector control. The SL:SCC solution did not exhibit any cytotoxicity against any of the five test strains at the dose levels used. This product is considered non-mutagenic.

Claims

1. An aqueous formulation for parenteral administration, comprising a compound of formula (I) or a salt thereof complexed with Cu ions. Formula (I) The formulation further comprises: Approximately 7% to approximately 13% (v / v) ethanol; Sodium chloride, approximately 0.3% to approximately 1.2% (w / v); and About 0.02 to about 0.1% (w / v) gentianic acid or its salt; The formulation described therein has a pH of about 4 to about 8.

2. The aqueous formulation according to claim 1, wherein the formulation comprises: Approximately 10% (v / v) ethanol; Approximately 0.9% (w / v) sodium chloride; Approximately 0.06% (w / v) gentic acid or its salt; The formulation contains acetate; and The formulation has a pH of approximately 6.

0.

3. An aqueous formulation for parenteral administration, comprising a compound of formula (I) or a salt thereof complexed with Cu ions. Formula (I) The formulation further comprises: Approximately 7% to approximately 13% (v / v) ethanol; Sodium chloride, approximately 0.3% to approximately 1.2% (w / v); About 0.02 to about 0.1% (w / v) gentianic acid or its salts; and Approximately 1.0 to approximately 4.0 mg / mL of L-methionine or its salts; The formulation described therein has a pH of about 4 to about 8.

4. The aqueous formulation according to claim 3, wherein the formulation comprises: Approximately 10% (v / v) ethanol; Approximately 0.9% (w / v) sodium chloride; Approximately 0.06% (w / v) gentic acid or its salt; and Approximately 2.5 mg / mL of L-methionine or its salt; The formulation contains acetate; and The formulation has a pH of approximately 6.

0.

5. The aqueous formulation according to any one of claims 1 to 4, wherein the compound of formula (I) is in the form of an acetate.

6. The aqueous formulation according to any one of claims 1 to 5, wherein the formulation comprises acetate as a buffer.

7. The aqueous formulation according to any one of claims 1 to 6, wherein the gentianate salt is sodium gentianate.

8. The aqueous formulation according to any one of claims 1 to 7, wherein the concentration of gentianic acid or its salt does not exceed 0.056% (w / v).

9. The aqueous formulation according to any one of claims 1 to 7, wherein the Cu ion is a Cu radioisotope.

10. The aqueous formulation according to claim 9, wherein the Cu radioisotope is selected from... 60 Cu、 61 Cu、 64 Cu and 67 Cu.

11. A method for preparing an aqueous formulation comprising a compound of formula (I) complexed with Cu ions, the method comprising the following steps: i) Prepare a buffer solution of acetate, wherein the buffer solution further comprises ethanol and gentianic acid or a salt thereof; ii) Dissolve the compound of formula (I) or a salt thereof in the buffer solution obtained in step i); iii) Add the Cu ion solution to the solution obtained in step ii); iv) Filter the solution obtained in step iii) onto the stationary phase; and v) Wash the stationary phase from step iv) with ethanol and brine; To recover aqueous formulations containing compounds of formula (I) or their salts that are complexed with Cu ions.

12. A method for preparing an aqueous formulation comprising a compound of formula (I) complexed with Cu ions, the method comprising the following steps: i) Prepare a buffer solution of acetate, wherein the buffer solution further comprises ethanol and gentianic acid or a salt thereof; ii) Dissolve the compound of formula (I) or a salt thereof in the buffer solution obtained in step i); iii) Add the Cu ion solution to the solution obtained in step ii); iv) Filter the solution obtained in step iii) onto the stationary phase; and v) Wash the stationary phase from step iv) into a solution of L-methionine with ethanol and saline. To recover aqueous formulations containing compounds of formula (I) or their salts that are complexed with Cu ions.

13. The method according to claim 11 or 12, wherein the acetate in the buffer solution is ammonium acetate.

14. The method according to any one of claims 11 to 13, wherein the concentration of the acetate buffer solution is about 0.1 mol / L.

15. The method according to any one of claims 11 to 14, wherein the concentration of ethanol in the buffer solution is about 4% to about 10% (v / v).

16. The method according to any one of claims 11 to 15, wherein the buffer solution contains sodium gentianate.

17. The method according to any one of claims 11 to 16, wherein the solution of Cu ions is a hydrochloric acid solution.

18. The method of claim 17, wherein the concentration of the hydrochloric acid solution is from about 0.01 to about 0.10 mol / L.

19. The method according to claim 17 or 18, wherein the concentration of the hydrochloric acid solution is about 0.02 mol / L.

20. The method according to any one of claims 11 to 19, wherein the Cu ions are selected from... 60 Cu、 61 Cu、 64 Cu and 67 Cu radioactive isotopes.

21. The method according to any one of claims 11 to 20, wherein the Cu ions are obtained from a chloride salt of Cu ions.

22. The method according to claim 12, wherein the concentration of the L-methionine solution is about 2.5 mg / mL.

23. An aqueous formulation prepared by the method according to any one of claims 11 to 22.

24. A kit for preparing an aqueous formulation for parenteral administration comprising a compound of formula (I) or a salt thereof complexed with Cu ions, said kit comprising: Formula (I) A container containing a lyophilized compound of formula (I) or a salt thereof; Containers containing solutions of Cu ions; and The instructions for preparing an aqueous formulation according to any one of claims 1 to 10 include the addition of a buffer solution of ethanol, sodium chloride, and gentian acid or a salt thereof.

25. A kit for preparing an aqueous formulation for parenteral administration comprising a compound of formula (I) or a salt thereof complexed with Cu ions, said kit comprising: Formula (I) A container containing a lyophilized compound of formula (I) or a salt thereof; Container for a solution containing Cu ions; Containers containing buffer solutions of ethanol, sodium chloride, and gentianic acid or its salts; and The instructions for preparing an aqueous formulation according to any one of claims 1 to 10 include the addition of a buffer solution of ethanol, sodium chloride, and gentian acid or a salt thereof.

26. The kit according to claim 24 or 25, wherein the container containing a buffer solution of ethanol, sodium chloride and gentianic acid further comprises L-methionine or a salt thereof.

27. A method for radiographic imaging, diagnosis, or treatment of cancer, the method comprising administering to a subject in need of the aqueous formulation according to any one of claims 1 to 10.

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