A novel kit for the radiopharmaceutical preparation of radiometal-labeled chelate-functionalized targeting conjugates

Abstract

The subject of the present invention is a lyophilized kit formulation for the preparation of a radioactive metal-labeled chelate-functionalized targeting conjugate, said kit formulation comprising: - Chelate-functionalized GRP receptor targeting conjugates, including: i. a chelating moiety; ii. at least one targeting moiety which is a GRP receptor (GRPr) targeting peptide; and iii. optionally, at least one linker connecting the chelating moiety and the GRP receptor (GRPr) targeting moiety; and - at least one GRP receptor (GRPr) targeting moiety, - at least one non-reducing sugar selected from the group consisting of trehalose and sucrose, and - at least one radiation stabilizer selected from the group consisting of ascorbic acid, ascorbate salts, gentisic acid, gentisate salts, or mixtures thereof. Includes.

Description

[Technical field]

[0001] The present invention relates to: - chelate-functionalized targeting conjugates, - at least one non-reducing sugar selected from the group consisting of trehalose and sucrose, at least one radiation stabilizer selected from the group consisting of ascorbic acid, ascorbate salts, gentisic acid, gentisate salts, or mixtures thereof, The present invention relates to a lyophilized kit formulation for preparing a radiometal-labeled chelate-functionalized targeting conjugate comprising: [Background technology]

[0002] Radioactive metal-labeled peptides, especially 68 The use of kit formulations for preparing Ga-labeled peptides has been described in the prior art:

[0003] International Publication No. WO2016 / 030103 (Wouters et al.) discloses a radiolabeling kit.

[0004] The kit includes an appropriate amount of acetate or acetate buffer, a chelating functionalized targeting agent, and a metal inhibitor that is a co-chelator capable of inactivating contaminating metals.

[0005] The application does not address the issue of long-term stability of the kit formulation during storage.

[0006] International Publication No. WO2016 / 030104 (Wouters et al.) discloses radioactive metal labeling methods.

[0007] The method involves the use of a "metal inhibitor" during the radiometal labeling reaction to increase the radiolabeling yield of the radiometal labeled with a chelator-functionalized targeting agent.

[0008] The application does not address the issue of long-term stability of the kit formulation during storage.

[0009] Nassiri et al. disclose a kit for preparing gallium Ga 68 dotatate (Nassiri et al.: coalitionforpetdrugapproval.files.wordpress.com / 2016 / 06 / nassiri-paulus-kit-for-ga-68-dotatate.pdf).

[0010] The kit contains the somatostatin analogue dotatate, phenanthroline (as a metal sequesting agent), gentisic acid and mannitol. The kit has a shelf life of 12 months at room temperature.

[0011] Pandey et al. 68 We describe a single-vial AMBA kit for Ga labeling (J Radioanal Nucl Chem, 2016, 1115-1124). The lyophilized kit formulation contains AMBA peptide, ascorbic acid, and sodium acetate. The kit is stored at -20 °C until further use.

[0012] de Barros et al. have described a kit formulation for the preparation of 99mTc-labeled HYNIC-bAla-Bombesin(7-14) (Appl. Rad. and Isotopes, 2012, 1440-2445). 99m It contains tin(II) chloride for Tc labeling. The stability of the kit formulation was confirmed at -20°C.

[0013] Vats et al. describe a kit containing peptides and sodium acetate (Journal of Pharmaceutical and Biomedical Analysis, 2019, 39-44).

[0014] The problem that the present invention aims to solve is to provide a lyophilized kit formulation for the preparation of a radiometal-labeled chelate-functionalized targeting conjugate, in particular a radiometal-labeled chelate-functionalized GRP receptor (GRPr) targeting conjugate, such as: - can be readily used to prepare radiometal-labeled chelate-functionalized targeting conjugates. - used with solutions derived from radioactive metal generators or cyclotrons, without reducing the radioactive metals in a preparation step. - 68 When labeling with Ga, a variety of generators (and elution methods, e.g., amounts and concentrations of HCl) can be used. - To provide radiometal-labeled chelate-functionalized targeting conjugates with little or no radiolytic degradation. - providing radiometal-labeled chelate-functionalized targeting conjugates with high purity of 90% or more, preferably 92% or more, more preferably 95% or more. - Meet regulatory requirements for lyophilized parenterals, including uniformity of dosage, stability, cake and cake appearance. - The chelate-functionalized targeting conjugate can be stored at room temperature for at least one year without degradation (the purity of the chelate-functionalized peptide conjugate is 90% or more, preferably 95% or more, more preferably 98% or more).

[0015] Nassiri et al. and WO2016030103 (Wouters et al.) report that the compound is stable at room temperature for 12 months, and 68 It teaches the use of a sugar alcohol (mannitol) as an excipient in a kit formulation of a chelate-functionalized peptide to obtain a composition that can be easily labeled with a Ga isotope. Despite this teaching, the sugar alcohol mannitol was found to be insufficient for the production of a lyophilized kit formulation containing a chelate-functionalized GRPr targeting peptide.

[0016] Pandey et al. describe a one-vial kit. The amount of buffer (sodium acetate) present in the kit is pre-defined, making the use of the kit inflexible to different generators (variations in the amount and concentration of HCl). Storage of these kits is below -20 °C. Furthermore, the sodium acetate present is not a suitable excipient for lyophilization.

[0017] The kit described by Vats et al. does not contain a radioactive scavenger, which is required to stabilize the radiometal-labeled chelate-functionalized targeting conjugate, especially at high radioactivity levels. In addition, the kit contains sodium acetate. Due to the glass temperature of the components, lyophilization according to the regulatory requirements for lyophilization of parenteral drugs, including dosage uniformity and stability, cannot be achieved.

[0018] In contrast to the use of mannitol (a sugar alcohol), kit formulations containing non-reducing sugars have been found to specifically meet the following requirements for a lyophilized kit formulation: - Facile preparation of radiometal-labeled chelate-functionalized targeting conjugates. - High purity of radiometal-labeled chelate-functionalized targeting conjugates. - Meet regulatory requirements for lyophilization of parenteral drugs, including dosage uniformity and stability. - High stability during storage at room temperature. Summary of the Invention

[0019] The present invention relates to an improved method for the radiopharmaceutical preparation of radiometal-labeled chelate-functionalized targeting conjugates through the use of a specific kit formulation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Unless otherwise defined, all technical terms, designations and other scientific terms used herein are intended to have the meanings commonly understood by those skilled in the art to which this application pertains. In some cases, terms having commonly understood meanings are defined herein for clarity and / or ready reference, but the inclusion of such definitions herein should not necessarily be interpreted as representing a substantial difference from what is commonly understood in the art.

[0021] As used in this specification and the appended claims, the singular forms "a," "and," and "the" include plural references unless the context clearly dictates otherwise.

[0022] As used in this specification and the appended claims, the term "agent" has the same meaning as the term "moiety" and both terms are interchangeable and can be substituted for each other.

[0023] The invention illustratively described herein may suitably be practiced in the absence of any element(s), limitation(s) not specifically disclosed herein. Thus, for example, in each instance herein, any of the terms "comprising," "consisting essentially of," and "consisting of" may be replaced with any of the other two terms.

[0024] While the term "one or more", e.g., one or more members of a group of members, is itself explicit, by way of further illustration, the term specifically encompasses reference to any one of said members, or any two or more of said members, e.g., any >3, >4, >5, >6 or >7, etc. of said members, and up to all of said members.

[0025] All documents cited herein are incorporated by reference in their entirety.

[0026] The terms "protein," "peptide," and "polypeptide" are used interchangeably to refer to an amino acid polymer or a set of two or more interacting or bound amino acid polymers. The terms apply to amino acid polymers in which one or more amino acid residues are artificial chemical mimetics of a corresponding naturally occurring amino acid, as well as to naturally occurring and non-naturally occurring amino acid polymers.

[0027] The term "amino acid" refers to naturally occurring and synthetic amino acids, as well as amino acid analogs and amino acid metrics that function similarly to naturally occurring amino acids. Naturally occurring amino acids are those that are genetically encoded or subsequently modified, such as hydroxyproline, γ-carboxyglutamic acid, and O-phosphoserume. Amino acid analogs refer to compounds that have the same basic chemical structure as naturally occurring amino acids, i.e., carbons attached to hydrogen, carboxyl groups, amino groups, and R groups, such as homoserine, norleucine, methionine sulfoxide, and methionine methylsulfonium. Such analogs have modified R groups (e.g., norleucine) or modified peptide backbones, but retain the same basic chemical structure as naturally occurring amino acids. Amino acid mimetics refer to compounds that have a structure that differs from the general chemical structure of an amino acid, but function similarly to a naturally occurring amino acid. The terms "non-naturally occurring amino acid" and "non-natural amino acid" refer to non-naturally occurring amino acid analogs, synthetic amino acids, and amino acid mimetics. Amino acids may be referred to herein by either their commonly known three letter symbols or by the one-letter symbols recommended by the IUPAC-IUB Biochemical Nomenclature Commission. Nucleotides may also be referred to by their commonly accepted single-letter codes.

[0028] The term "labeling buffer" refers to a solution that must be non-toxic, must effectively maintain a pH within the range of 3.0 to 5.0, does not compete with gallium-68 ions, and preferably has a low capacity for metal chelation relative to the capacity of the chelator combined with the targeting agent. It must also be tolerant to small changes in the volume of the generator eluate (and therefore the volume of HCl), i.e., it must be strong enough to maintain the pH in the desired range even with a 10% change in the volume of the eluate. Suitable buffers include, for example, acetate, formate, tartrate, citrate, phosphate, etc.

[0029] The term "radiopharmaceutical preparation" or "radiopharmaceutical composition" refers to a composition comprising a radioactive metal complex of the present invention in a form suitable for human administration. For administration to humans, the radiopharmaceutical preparation must be sterile. Alternatively, the radiopharmaceutical preparation of the present invention may be provided in a unit dose form injectable into humans, for example, a pre-filled sterile syringe. The syringe containing the unit dose will also be supplied within a syringe shield (to protect the operator from potential radioactive dose).

[0030] In the following text, different aspects or embodiments of the invention are defined in more detail. All aspects or embodiments thus defined may be combined with each of the other aspects or embodiments, unless otherwise stated. In particular, features indicated as preferred or advantageous in one embodiment may be combined with other embodiments or embodiments indicated as preferred or advantageous.

[0031] The subject of the present invention is - chelate-functionalized targeting conjugates, - at least one non-reducing sugar selected from the group consisting of trehalose and sucrose, at least one radiation stabilizer selected from the group consisting of ascorbic acid, ascorbate salts, gentisic acid, gentisate salts, or mixtures thereof; A lyophilized kit formulation for the preparation of a radiometal-labeled chelate-functionalized targeting conjugate comprising:

[0032] The subject of the present invention is a lyophilized kit formulation for the preparation of a radiometal-labeled chelate-functionalized targeting conjugate, in particular the concentration of non-reducing sugar in said formulation is between 10 and 600 μmol, preferably between 20 and 500 μmol, more preferably between 50 and 300 μmol.

[0033] In one embodiment of the kit formulation of the present invention, the formulation contains 5 to 250 mg, preferably 10 to 100 mg, of trehalose.

[0034] In one embodiment of the kit formulation of the present invention, the formulation contains 5 to 250 mg, preferably 10 to 100 mg, of sucrose.

[0035] In another embodiment of the kit formulation of the present invention, a mixture of non-reducing sugars is used.

[0036] In one embodiment of the kit formulation of the present invention, the radiation stabilizer is selected from the group consisting of ascorbic acid, an ascorbate salt, or a mixture thereof.

[0037] In one particular embodiment of the kit formulation of the present invention, the radiation stabilizer is ascorbic acid.

[0038] In one embodiment of the kit formulation of the present invention, the concentration of the radiation stabilizer in the formulation is 1 to 500 μmol, preferably 5 to 250 μmol, and more preferably 10 to 100 μmol.

[0039] In one embodiment of the kit preparation of the present invention, the amount of ascorbic acid in the preparation is 1 to 20 mg, more preferably 1 to 10 mg.

[0040] In one embodiment of the kit formulation of the invention, the chelate-functionalized targeting conjugate comprises: -chelating agents or moieties, - optionally at least one linker linking the chelating moiety and the targeting moiety; and - at least one targeting agent or moiety: Includes.

[0041] As used herein, a "chelate-functionalized targeting conjugate" refers to a targeting agent / moiety that can be labeled with a radioisotope, such as gallium-68, by a chelator / moiety linked to the targeting agent. Optionally, at least one linker is present to link the chelator / moiety and the targeting agent / moiety.

[0042] Preferred chelators for functionalizing targeting agents radiolabeled with gallium-68 are those that are capable of functionalizing Ga for at least a period of time sufficient for diagnostic investigations using such radiolabeled targeting agents. 3+ ,especially 68 Ga 3+ (a radioisotope generator eluted from a germanium-68 / gallium-68 generator with HCl) Suitable chelating agents include aliphatic amines, linear or macrocyclic amines, such as macrocyclic amines with tertiary amines.

[0043] Examples of these suitable chelating agents are not limited, but preferably include DOTA, NOTA and its derivatives, such as TACN, TACN-TM, DTAC, H3NOKA, NODASA, NODAGA, NOTP, NOTPME, PrP9, TRAP, Trappist Pr, NOPO, TETA; tris(hydroxypyridinone) (THP) and derivatives, open chain chelates, such as HBED, DFO or desferrioxamine or desferal, EDTA, 6SS, B6SS, PLED, TAME, YM103; NTP(PRHP)3; H2dedpa and its derivatives, such as H2dedpa-1, 2-H2dedpa, H2dp-bb-NCS, and H2dp-N-NCS; (4,6-Me02sal)2-BAPEN; and citrate and its derivatives. In one embodiment of the kit formulation of the present invention, the chelating moiety is selected from the group consisting of NOTA and its derivatives and / or DOTA and its derivatives. In one particular embodiment of the kit formulation of the invention, the chelating moiety is DOTA.

[0044] The targeting agent can be a peptide, e.g., a peptide containing 2-20 amino acids, a polypeptide, a protein, a vitamin, a saccharide, e.g., a monosaccharide or polysaccharide, an antibody and its derivatives, e.g., a nanobody, a diabody, an antibody fragment, a nucleic acid, an aptamer, an antisense oligonucleotide, an organic molecule, or other biomolecule capable of binding to a specific diagnostic target or expressing a specific metabolic activity.

[0045] The targeting agent described herein preferably has biological targeting ability.Non-limiting examples of suitable targeting agents include molecules that target VEGF receptors, analogs of bombesin or molecules that target GRP receptors (GRPr), molecules that target somatostatin receptors, RGD peptides or molecules that target ανβ3 and ανβ5, Annexin V or molecules that target apoptotic processes, and molecules that target estrogen receptors.More generally, a list of targeting molecules (organic or non-organic) functionalized by chelating agents is described in the document "Velikyan et al., Theranostic 2014, Vol. 4, Issue 1 "Prospective of 68Ga-Radiopharmaceutical Development".

[0046] The peptides of the invention may be of natural or synthetic origin, but are preferably of synthetic origin.

[0047] In one embodiment of the kit formulation of the invention, the targeting moiety of the chelate-functionalized peptide conjugate is a GRP receptor (GRPr) targeting molecule, more preferably ― Gln-Trp-Ala-Val-Gly-His, ― D-Phe-Gln-Trp-Ala-Val-Gly-His, ― Gln-Trp-Ala-Val-Gly-His-Sta, ― D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta, ― Gln-Trp-Ala-Val-Gly-His-Leuψ(CHOH-CH 2 )-(CH 2 ) 2 -CH 3 , ― D-Phe-Gln-Trp-Ala-Val-Gly-His-Leuψ(CHOH- CH 2 )-(CH 2 ) 2 -CH3 , ― D-Phe-Gln-Trp-Ala-Val-Gly-His-Leuψ(CH 2 NH), ― Gln-Trp-Ala-Val-Gly-His-Leuψ(CH 2 NH), ― Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH 2 or ― D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH 2 The GRPr targeting peptide sequence comprises a GRPr targeting peptide sequence selected from the group consisting of:

[0048] In one embodiment of the kit formulation of the invention, the chelator-functionalized peptide conjugate comprises: -DOTA-4-amino-1-carboxymethyl-piperidine-D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH 2 , -NOTA-4-amino-1-carboxymethyl-piperidine-D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH 2 , -NODAGA-4-amino-1-carboxymethyl-piperidine-D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH 2 : is selected from the group consisting of:

[0049] In one embodiment of the kit formulation of the invention, the chelate-functionalized peptide conjugate is DOTA-4-amino-1-carboxymethyl-piperidine-D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH 2 It is.

[0050] In one embodiment of the kit formulation of the invention, at least one linker is present to link the chelator / moiety and the targeting agent / moiety. The linker of the chelator-functionalized targeting conjugate is selected from the group consisting of bonds, natural amino acids, unnatural amino acids, linear diamines, cyclic diamines, linear carboxylic acids, cyclic carboxylic acids, polyethylene glycol (PEG) and combinations thereof. The linker may or may not contain other groups such as an aliphatic chain of up to 5 carbons and may consist of a peptide sequence of about 5-9 amino acids. Preferred linker groups -poly-Lys-, -poly-Glu-, -(Gly)Z-Glu-(Lys) 3 -, (Gly) 2 Glu-Lys-Glu-Lys-, (Phe) 2 -(CH 2 )s-, (Lys) 6 -Gly-, -(Gly) 3 -(DGlu) 3 -, and -(Gly)3(aminocaproic acid)2-.

[0051] In one embodiment of the kit formulation of the invention, the linker is selected from the group consisting of natural amino acids, unnatural amino acids, linear diamines, cyclic diamines, linear carboxylic acids, cyclic carboxylic acids, polyethylene glycol (PEG), and combinations thereof.

[0052] More preferably, the linker is selected from the group consisting of 4-amino-1-carboxymethylpiperidine, (R,S)-diaminoacetic acid, PEG1-24, Sar-10, 8-aminooctanoic acid, 6-aminocaproic acid, 4-(2-aminoethyl)-1-carboxymethylpiperazine-, diaminobutyric acid, hippuric acid, 4-amino-1-Boc-piperidine-4-carboxylic acid, gly-aminobenzoic acid, 5-amino-3-oxa-pentyl-succinic acid, PEG1-24-4-amino-1-carboxymethylpiperidine, Dab (shikimic acid), (D-Gln)x, (D-Asn)x.

[0053] In one embodiment of the kit formulation of the invention, the linker is 4-amino-1-carboxymethyl-piperidine.

[0054] In one embodiment of the kit formulation of the present invention, the kit formulation comprises 5-500 nmol of a chelate-functionalized targeting conjugate, preferably 5-150 nmol of a chelate-functionalized targeting conjugate, more preferably 10-100 nmol of a chelate-functionalized targeting conjugate.

[0055] In one embodiment of the kit formulation of the invention, the formulation in a lyophilized state can be a crystalline, partially crystalline, partially amorphous or amorphous formulation.

[0056] In one embodiment of the kit formulation of the present invention, the formulation is an amorphous formulation.

[0057] In one embodiment of the kit formulation of the invention, the formulation has a residual moisture content of 1% or less, preferably 0.5% or less.

[0058] In one embodiment of the kit formulation of the present invention, the lyophilized formulation is sterile.

[0059] In one embodiment of the kit formulation of the invention, the degradation rate of the chelator-functionalized targeting conjugate in the formulation after storage at 25° C. / 60% RH for 12 months is 10% or less, preferably 5% or less, and more preferably 3% or less.

[0060] In one embodiment of the kit formulation of the invention, the radiochemical purity of the radiometal-labeled chelate-functionalized targeting conjugate prepared from the formulation is 90% or more, preferably 93% or more, and more preferably 95% or more after storage at 25° C. / 60% RH for 12 months.

[0061] In one embodiment of the kit formulation of the invention, the formulation for the preparation of a chelate-functionalized targeting conjugate is labeled with a trivalent or divalent radioactive cation.

[0062] In one embodiment of the kit formulation of the invention, the formulation for the preparation of a chelate-functionalized targeting conjugate is labeled with a trivalent radioactive metal cation.

[0063] In one embodiment of the kit formulation of the invention, the formulation for the preparation of a chelate-functionalized targeting conjugate is labeled with a divalent radioactive metal cation.

[0064] In one embodiment of the kit formulation of the invention, the formulation for the preparation of a chelate-functionalized targeting conjugate labeled with an isotope is selected from the group consisting of Ga, Cu, Lu, Y, Pb, Ac, Bi, Sc, Th.

[0065] In one embodiment of the kit formulation of the invention, the formulation for the preparation of an isotopically labeled chelate-functionalized targeting conjugate comprises: 68 Ga, 64 Cu, 67 Cu, 177 Lu, 86 Y, 90 Y, 212 Pb, 225 Ac, 213 Bi, 44 Sc, 227 Th.

[0066] In one embodiment of the kit formulation of the invention, the formulation for the preparation of an isotopically labeled chelate-functionalized targeting conjugate comprises: 68 Ga, 64 Cu, 67 Cu, 177 Lu, 86 Y, 90 Y, 212 Pb, 225 Ac, 213 Bi, 44 Sc, 227 Th or 18 F-Al.

[0067] In one embodiment of the kit formulation of the invention, the formulation for the preparation of an isotopically labeled chelate-functionalized targeting conjugate comprises: 68 Ga, 64 Cu, 67 Cu, 177 Lu, 86 Y, 90 Y, 212 Pb, 225 Ac, 213 Bi, 44 Sc or 18 F-Al.

[0068] In one particular embodiment of the kit formulation of the present invention, the formulation for the preparation of the chelate-functionalized targeting conjugate comprises 68 Labeled with Ga.

[0069] In one embodiment of the kit formulation of the invention, the formulation for the preparation of a chelate-functionalized targeting conjugate comprises: 177 It is labeled with Lu.

[0070] In one embodiment of the kit formulation of the invention, the formulation for the preparation of a chelate-functionalized targeting conjugate comprises: 18 Labeled with F-Al.

[0071] The subject of the present invention is also a method for preparing a radiometal-labeled chelate-functionalized targeting conjugate by using the kit formulation according to the invention, said method comprising the steps of: - mixing a solution of a radioactive metal with the kit formulation according to any one of the preceding embodiments; - optionally adding at least one labelling buffer or a mixture of labelling buffers, - complexing a chelator-functionalized targeting conjugate according to any one of the preceding embodiments with a radioactive metal: Includes.

[0072] In one embodiment, the method further comprises: - adding a diluent after the complex formation step, and / or - dispensing an amount of a dose of a radioactive metal-labeled chelate-functionalized targeting conjugate: Further includes:

[0073] In one embodiment, a method for preparing a radiometal-labeled chelate-functionalized targeting conjugate using said kit formulation according to the invention comprises: - mixing a solution of a radioactive metal with the kit formulation according to any one of the preceding embodiments; - optionally adding at least one labelling buffer or a mixture of labelling buffers, - complexing a chelate-functionalized targeting conjugate according to any one of the preceding embodiments with a radiometal; - adding a diluent after the step of complex formation, and / or - dispensing a dose of the radioactive metal-labeled chelate-functionalized targeting conjugate. Includes.

[0074] In one embodiment, the method for preparing the radiopharmaceutical is performed manually.

[0075] In another embodiment, - adding a solution of the radiopharmaceutical; - optionally adding at least one (labeling) buffer, - carrying out complexation of a chelate-functionalized targeting conjugate, or - Optionally, adding a diluent, preferably selected from the group consisting of water for injection, physiological saline or physiological buffer. For this purpose, a device is used.

[0076] In one particular embodiment of the method according to the invention, the complex formation step is carried out at a temperature between 0 and 150°C, preferably at 25°C (room temperature) or between 50°C and 150°C, more preferably between 80°C and 120°C, even more preferably between 90°C and 110°C.

[0077] In one particular embodiment of the method according to the invention, for complex formation, the formulation may be heated using any type of heater or microwave.

[0078] In one particular embodiment of the method according to the present invention, the complex formation is carried out for 0.5 min to 30 min, preferably 1 min to 20 min, preferably 1 min to 10 min, more preferably 5 min to 10 min.

[0079] In one particular embodiment of the method according to the invention, said (labelling) buffer is selected from the group consisting of acetate buffer, formate buffer.

[0080] In one particular embodiment of the method according to the invention, the complex formation is carried out at a pH value between 2.5 and 5, more preferably between 3.5 and 4.5.

[0081] In one particular embodiment of the method according to the invention, the chelate-functionalized targeting conjugate obtained by this method exhibits a purity of 90% or more, preferably 92% or more, more preferably 95% or more.

[0082] The present invention also relates to radiopharmaceutical compositions comprising any of the above radiometal-labeled chelate-functionalized targeting conjugates of the present invention.

[0083] In one embodiment, the radiopharmaceutical composition of the invention comprises: -Radiometal-labeled chelate-functionalized targeting conjugates of the present invention - at least one non-reducing sugar selected from the group consisting of trehalose and sucrose, and at least one radiation stabilizer selected from the group consisting of ascorbic acid, ascorbate salts, gentisic acid, gentisate salts, or mixtures thereof; Includes.

[0084] In one particular embodiment, the subject of the present invention is - a vial containing the lyophilized kit formulation according to the invention as described above - a vial or syringe containing at least one labeling buffer or a mixture of labeling buffers, and / or - Vial or syringe containing a solution of radioactive metal: A kit comprising:

[0085] In a preferred embodiment, the kit preparations are sterile.

[0086] In a preferred embodiment, the labeling buffer is sterile.

[0087] In a preferred embodiment, the diluent is sterile.

[0088] In a preferred embodiment, the method for preparing a radiopharmaceutical is to provide a sterile solution of a radiometal-labeled chelate-functionalized targeting conjugate, preferably said solution usable for administration to humans.

[0089] With the above background in mind, the following sequentially numbered embodiments provide further specific aspects of the present invention:

[0090] 1. A lyophilized kit formulation for the preparation of a radioactive metal-labeled chelate-functionalized targeting conjugate, comprising: - Chelate-functionalized targeting conjugates at least one non-reducing sugar selected from the group consisting of trehalose and sucrose at least one radiation stabilizer selected from the group consisting of ascorbic acid, ascorbate salts, gentisic acid, gentisate salts, or mixtures thereof; The kit preparation comprising:

[0091] 2. The kit formulation according to embodiment 1, wherein the concentration of the non-reducing sugar in the formulation is 10 to 600 μmol, preferably 20 to 500 μmol, more preferably 50 to 300 μmol.

[0092] 3. The kit formulation according to embodiment 1 or 2, wherein said kit formulation comprises 5 to 250 mg, preferably 10 to 100 mg, of trehalose.

[0093] 4. The kit formulation according to embodiment 1 or 2, wherein the kit formulation comprises 5 to 250 mg, preferably 10 to 100 mg, of sucrose.

[0094] 5. The kit formulation of any one of embodiments 1-4, wherein the radiation stabilizer is selected from the group consisting of ascorbic acid, an ascorbate salt, or a mixture thereof.

[0095] 6. The kit formulation according to any one of embodiments 1 to 5, wherein the concentration of the radiation stabilizer in the formulation is 1 to 500 μmol, preferably 5 to 250 μmol, more preferably 10 to 100 μmol.

[0096] 7. The kit formulation according to any one of embodiments 1 to 6, wherein the amount of ascorbic acid in the formulation is 1 to 20 mg, more preferably 1 to 10 mg.

[0097] 8. A kit formulation according to any one of the preceding embodiments, wherein the chelate-functionalized targeting conjugate is - Chelating moiety - optionally at least one linker connecting the chelating moiety and the targeting moiety, and - At least one targeting segment The kit preparation comprising:

[0098] 9. The kit formulation of embodiment 8, wherein the chelating moiety is selected from the group consisting of TACN, TACN-TM, DTAC, H3NOKA, NODASA, NODAGA, NOTP, NOTPME, PrP9, TRAP, Trappist Pr, NOPO, TETA; tris(hydroxypyridinone) (THP) and derivatives, open chain chelates such as HBED, DFO or desferrioxamine or desferal, EDTA, 6SS, B6SS, PLED, TAME, YM103; NTP(PRHP)3; H2dedpa and its derivatives such as H2dedpa-1, 2-H2dedpa, H2dp-bb-NCS, and H2dp-N-NCS; (4,6-Me02sal)2-BAPEN; and citrate and its derivatives.

[0099] 10. The kit formulation of embodiment 8, wherein the chelating moiety is NOTA and its derivatives and / or DOTA and its derivatives, preferably DOTA.

[0100] 11. The kit formulation of any one of embodiments 8 to 10, wherein the linker is selected from the group consisting of a bond, a natural amino acid, an unnatural amino acid, a linear diamine, a cyclic diamine, a linear carboxylic acid, a cyclic carboxylic acid, polyethylene glycol (PEG), and combinations thereof.

[0101] 12. The kit formulation according to any one of embodiments 8 to 11, wherein the linker is selected from the group consisting of 4-amino-l-carboxymethylpiperidine, (R,S)-diaminoacetic acid, PEG1-24, Sar-10, 8-aminooctanoic acid, 6-aminocaproic acid, 4-(2-aminoethyl)-l-carboxymethylpiperazine, diaminobutyric acid, hippuric acid, 4-amino-l-Boc-piperidine-4-carboxylic acid, gly-aminobenzoic acid, 5-amino-3-oxa-pentyl-succinic acid, PEG1-24-4-amino-l-carboxymethylpiperidine, Dab (shikimic acid), (D-Gln)x, (D-Asn)x.

[0102] 13. The kit formulation of any one of embodiments 8 to 12, wherein the linker is 4-amino-1-carboxymethyl-piperidine.

[0103] 14. The kit formulation according to any one of embodiments 8 to 13, wherein the targeting moiety is selected from a molecule targeting the VEGF receptor, an analogue of bombesin or a molecule targeting the GRP receptor (GRPr), a molecule targeting the somatostatin receptor, an RGD peptide or a molecule targeting ανβ3 and ανβ5, Annexin V or a molecule targeting the apoptotic process, or a molecule targeting the estrogen receptor.

[0104] 15. The kit formulation of embodiment 14, wherein the GRP receptor (GRPr) targeting molecule is a GRPr targeting peptide.

[0105] 16. The GRP receptor (GRPr) targeting molecule is ― Gln-Trp-Ala-Val-Gly-His, ― D-Phe-Gln-Trp-Ala-Val-Gly-His, ― Gln-Trp-Ala-Val-Gly-His-Sta, ― D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta, ― Gln-Trp-Ala-Val-Gly-His-Leuψ(CHOH-CH 2 )-(CH 2 ) 2 -CH 3 , ― D-Phe-Gln-Trp-Ala-Val-Gly-His-Leuψ(CHOH- CH 2 )-(CH 2 ) 2 -CH 3 , ― D-Phe-Gln-Trp-Ala-Val-Gly-His-Leuψ(CH 2 NH), ― Gln-Trp-Ala-Val-Gly-His-Leuψ(CH 2NH), ― Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH 2 or ― D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH 2 15. The kit formulation of embodiment 14, comprising a peptide sequence selected from the group consisting of:

[0106] 17. The chelator-functionalized peptide conjugate comprises: -DOTA-4-amino-1-carboxymethyl-piperidine-D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH 2 , -NOTA-4-amino-1-carboxymethyl-piperidine-D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH 2 , -NODAGA-4-amino-1-carboxymethyl-piperidine-D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH 2 : The kit formulation according to any one of embodiments 1 to 16, selected from the group consisting of:

[0107] 18. The kit formulation according to any one of embodiments 1 to 17, wherein the kit formulation comprises 5 to 500 nmol of the chelate-functionalized targeting conjugate, preferably 5 to 150 nmol of the chelate-functionalized targeting conjugate, more preferably 10 to 100 nmol of the chelate-functionalized targeting conjugate.

[0108] 19. The kit formulation of embodiment 18, wherein the formulation is a crystalline, partially crystalline, partially amorphous or amorphous formulation.

[0109] 20. The kit formulation of embodiment 18 or 19, wherein the lyophilized formulation is sterile.

[0110] 21. The kit formulation of any one of embodiments 1-20, wherein the formulation has a residual moisture content of 1% or less, preferably 0.5% or less.

[0111] 22. The kit formulation of any one of embodiments 1-21, wherein the degradation of the chelating-functionalized targeting conjugate in the formulation after storage at 25° C. / 60% RH for 12 months is ≦10%, preferably ≦5%, more preferably ≦3%.

[0112] 23. A kit formulation according to any one of embodiments to 22, wherein the radiochemical purity of the radiometal-labeled chelate-functionalized targeting conjugate prepared from said formulation is 90% or more, preferably 93% or more, more preferably 95% or more after storage at 25°C / 60% RH for 12 months.

[0113] 24. The kit formulation according to any one of embodiments 1 to 23, wherein the formulation for the preparation of a chelate-functionalized targeting conjugate is labeled with a trivalent radioactive metal cation or a divalent radioactive metal cation.

[0114] 25. A formulation for the preparation of isotopically labeled chelate-functionalized targeting conjugates, comprising: 68 Ga, 64 Cu, 67 Cu, 177 Lu, 86 Y, 90 Y, 212 Pb, 225 Ac, 213 Bi, 44 Sc, or 18 The kit formulation according to any one of embodiments 1 to 24, wherein the kit formulation is selected from the group consisting of F-Al.

[0115] 26. A formulation for the preparation of a chelate-functionalized targeting conjugate, 68 The kit formulation according to any one of embodiments 1 to 25, which is labeled with Ga.

[0116] 27. A method for preparing a radioactive metal-labeled chelate-functionalized targeting conjugate using the kit formulation according to any one of embodiments 1 to 26, comprising: - mixing a solution of a radioactive metal with a kit formulation according to any one of the embodiments 1 to 26, - optionally adding at least one labelling buffer or a mixture of labelling buffers, - complexing the chelate-functionalized targeting conjugate according to any one of embodiments 1 to 26 with a radioactive metal: The method comprising:

[0117] 28. The method of embodiment 27, comprising: - adding a diluent after the complex formation step, and / or - dispensing a dose of a radioactive metal-labeled chelate-functionalized targeting conjugate. The method further comprises:

[0118] 29. The method according to embodiment 27 or 28, wherein the complexation step is carried out at a temperature between 0 and 150°C, preferably at 25°C (room temperature), or between 50°C and 150°C, more preferably between 80°C and 120°C, and even more preferably between 90 and 110°C.

[0119] 30. The method according to any one of embodiments 27 to 29, wherein the complexation is carried out by a heating means, preferably a heater or a microwave.

[0120] 31. The method according to any one of embodiments 27 to 30, wherein the complex formation is carried out for 0.5 min to 30 min, preferably 1 min to 20 min, preferably 1 min to 10 min, more preferably 5 min to 10 min.

[0121] 32. The method according to any one of embodiments 27 to 31, wherein the labeling buffer is selected from the group consisting of acetate buffer or formate buffer.

[0122] 33. The method according to any one of embodiments 27 to 32, wherein the chelate-functionalized targeting conjugate obtained by said method exhibits a purity of 90% or more, preferably 92% or more, more preferably 95% or more.

[0123] 34. The method according to any one of embodiments 27 to 33, wherein the complex formation is carried out at a pH value of 2.5 to 5, more preferably 3.5 to 4.5.

[0124] 35. A radioactive metal-labeled chelate-functionalized targeting conjugate obtainable by a method according to any one of embodiments 27 to 34.

[0125] 36. A radiopharmaceutical composition comprising a radiometal-labeled chelate-functionalized targeting conjugate according to embodiment 35.

[0126] 37. - a radioactive metal-labeled chelate-functionalized targeting conjugate according to embodiment 35. - at least one non-reducing sugar selected from the group consisting of trehalose and sucrose, at least one radiation stabilizer selected from the group consisting of ascorbic acid, ascorbate salts, gentisic acid, gentisate salts, or mixtures thereof, 1. A radiopharmaceutical composition comprising:

[0127] 38. - a vial containing a lyophilized kit formulation according to any one of the above embodiments 1 to 26 - a vial or syringe containing at least one labeling buffer or a mixture of labeling buffers, and / or - Vial or syringe containing a solution of radioactive metal: Kit including: EXAMPLES

[0128] Chemicals: --RM2-DOTA (GMP), ABX -Sodium acetate trihydrate - Sodium Formate (Sigma Aldrich 456020-25G) - Sodium L-ascorbate (Sigma), 11140-50g - L-Ascorbic acid (TraceSelect, Fluka, #: 05878; Sigma, #:PHR1068-2G; 20-80 mesh GMP, # 0938-05, JT Baker; Roth, #: 6288.1; Appli Chem, #: 141013.1208) - 2,5-dihydroxybenzoic acid (Sigma Aldrich #:149357) - 2,5 dihydroxybenzoic acid ultra-high purity (Sigma Aldrich #:39319-10x10 mg-F) - Water (TraceSelect, Fluka, 5305) - 30% Hydrochloric Acid (TraceSelect, Merck, 1.01514.0500) - 0.1 M HCl (1.06 ml 30% HCl, make up to 100 ml with TraceSelect water; Rotem Prod.#: K72001P; ABX Prod.#: HCl-103-G) - D-(+)-Trehalose dihydrate (Sigma Aldrich T9531-100G) - Polyvinylpyrrolidone K25 (Fluka, #:90268) - Polyvinylpyrrolidone 40 (Sigma, #: PVP40) -Trehalose (Fluka,#:PHR1344) -Sorbitol Fest (Sigma, #:PHR 1006) - D-Sorbitol (Sigma Aldrich #:97336-1kg-F) - Sucrose (Sigma, #:S7903) ― Polysorbat 80, (Fluka, #:59924-100) - Polysorbate 20 (Fluka,#:44112) - Mannitol (Sigma, #:PHR 1007) - D-Mannitol (Sigma, #:M8429) - 2-Hydroxyethylcellulose (Aldrich, #:308633) - Hypromellose (Sigma, #:H3785) - Dextran (Sigma, #:D9260-50) - D-(-)-Fructose (Sigma, #:F9048-100G) - D(+)-Glucose (Sigma, #:G7528-250G)

[0129] material: - Headspace vial, 9.5 ml, 3131-5245-K 1 Borosilicate glass, E&Z - TC-ELU-5 vial (15 ml) - "Vented vial adapter" by Helapet, #:IV0020 - Injection vial 10R, FIOLAX - Clear glass, NIPRO, #: MG037-002-0049-086 (delivered by Gilyos) - 10ml transparent SCHOTT (Fiolax) Type 1 Plus (SiO2) coated vial (delivered by Adelphi) -- Fluoro-Tec Septum, West Pharma, #:13194023 / 50 / GREY / SIL A DB (delivered by Gilyos) - Freeze Dry Stopper, FluoroTec coating, Bromobutyl 4023 / 50 grey, Westar RS P (supplied by Adelphi) - Syringe, Injekt(R) F Solo, 1ml, BBraun #: 9166017V - Syringe, Injekt(R) F Solo, 5 mL, BBraun #: 4606051V - Metal needle Sterican(R) Gr. 2, G 21 x 1 / 1”, 0.80 x 0.40, BBraun #: 4657527

[0130] ITLC: ― Agilent Technologies, ITLC-SG Chromatography paper, cat#: SGI0001

[0131] device: - Modular Lab Pharm Tracer + Heater Module HRM-6299 + Vial Adapter (3111-2603) (by Eckert & Ziegler) - [ 68 Ga]GaCl 3 : Generator IGG100-50M, Lot#: 1779-14, 1856-1 Eckert & Ziegler - [ 68 Ga]GaCl 3 : Generator IGG101-50MGallia Pharm, Lot#: LGHE03, Eckert & Ziegler - [ 68 Ga]GaCl 3 : Generator ID: GaG-16-151, ITG - pH-meter 766, Calimatic, Knick - Phosphor imager

[0132] Analysis method

[0133] The stability of the peptides in the lyophilized kit formulation was determined by analytical HPLC. The radiochemical purity of the radiometal-labeled chelate-functionalized targeting complexes was determined by HPLC and TLC.

[0134] Analytical HPLC method 1: [Table 1]

[0135] Analytical HPLC method 2: [Table 2]

[0136] TLC method: 1M ammonium acetate:methanol (1:1 V / V), retention factors (Rf) are as follows: uncomplexed Ga68 species, Rf = 0-0.1; 68Ga-RM2, Rf = 0.8-1.

[0137] Radiolabeling procedure

[0138] For Eckert & Ziegler generators IGG100 or IGG101, the generator is eluted with 5 mL of 0.1 M HCl and injected directly into the lyophilized kit formulation. Add labeling buffer (85 mg of sodium acetate in 200-300 µL of Traselect water, or 100 mg of sodium formate in 200-300 µL) and heat the vial in a boiling water bath for 8 min.

[0139] For the ITG generator, the generator is eluted with 4 mL of 0.05 M HCl and injected directly into the lyophilized kit formulation. Add labeling buffer (35 mg of sodium formate in 200-300 µL) and heat the vial in a boiling water bath for 8 min.

[0140] Preparation of lyophilized kit formulations

[0141] The freeze-drying cycle for a vial (fill volume 1 mL) is: - Freeze set point -45 °V, ramp rate 1 °C / min - Primary / secondary drying -30 °C - 40 °C, vacuum setting 40 mTorr: (Total cycle time: 48 hours) Includes.

[0142] [Table 3]

[0143] Evaluation of appearance and residual moisture of freeze-dried kit preparations [Table 4]

[0144] Evaluation of peptide stability in lyophilized kit formulations

[0145] Lyophilized kit formulations were stored at room temperature or at 40° C. / 60% relative humidity. Peptide stability was tested by analytical HPLC at baseline and at several time points (Tables 3 and 4).

[0146] Kit formulations containing mannitol (Comparative Formulations C, D, E) caused significant peptide degradation during storage at room temperature and at 40° C. No or only slight peptide degradation was observed in kit formulations containing the non-reducing sugars trehalose or sucrose. [Table 5] [Table 6]

[0147] Evaluation of radiochemical purity obtained after storage of kit preparations [Table 7]

Claims

1. 1. A lyophilized kit formulation for the preparation of a radioactive metal-labeled chelate-functionalized targeting conjugate, comprising: - a chelate-functionalized targeting conjugate comprising: i. a chelating moiety, ii. at least one targeting moiety, the targeting moiety being a GRP receptor (GRPr) targeting peptide; and iii. Optionally, at least one linker connecting the chelating moiety and the GRP receptor (GRPr) targeting moiety; - at least one non-reducing sugar selected from the group consisting of trehalose and sucrose, and at least one radiation stabilizer selected from the group consisting of ascorbic acid, ascorbate salts, gentisic acid, gentisate salts, or mixtures thereof, The kit preparation comprising:

2. The kit formulation according to claim 1, wherein the concentration of the non-reducing sugar in the formulation is 10 to 600 μmol, preferably 20 to 500 μmol, more preferably 50 to 300 μmol.

3. The kit formulation according to claim 1, wherein the concentration of the radiation stabilizer in the formulation is 1 to 500 μmol, preferably 5 to 250 μmol, more preferably 10 to 100 μmol.

4. The kit formulation of claim 1, wherein the amount of ascorbic acid in the formulation is 1 to 20 mg, more preferably 1 to 10 mg.

5. The kit formulation of claim 1, wherein the chelating moiety is selected from the group consisting of TACN, TACN-TM, DTAC, H3NOKA, NODASA, NODAGA, NOTP, NOTPME, PrP9, TRAP, Trappist Pr, NOPO, TETA; tris(hydroxypyridinone) (THP) and derivatives, open chain chelates such as HBED, DFO or desferrioxamine or desferal, EDTA, 6SS, B6SS, PLED, TAME, YM103; NTP (PRHP)3; H2dedpa and its derivatives such as H2dedpa-1, 2-H2dedpa, H2dp-bb-NCS, and H2dp-N-NCS; (4,6-Me02sal)2-BAPEN; and citrate and its derivatives.

6. 2. The kit formulation of claim 1, wherein the linker is selected from the group consisting of a bond, a natural amino acid, an unnatural amino acid, a linear diamine, a cyclic diamine, a linear carboxylic acid, a cyclic carboxylic acid, polyethylene glycol (PEG), and combinations thereof.

7. The GRP receptor (GRPr) targeting molecule is ― Gln-Trp-Ala-Val-Gly-His, ― D-Phe-Gln-Trp-Ala-Val-Gly-His, ― Gln-Trp-Ala-Val-Gly-His-Sta, ― D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta, ― Gln-Trp-Ala-Val-Gly-His-Leuψ(CHOH-CH 2 )-(CH 2 ) 2 -CH 3 、 ― D-Phe-Gln-Trp-Ala-Val-Gly-His-Leuψ(CHOH- CH 2 )-(CH 2 ) 2 -CH 3 、 ― D-Phe-Gln-Trp-Ala-Val-Gly-His-Leuψ(CH 2 NH)、 ― Gln-Trp-Ala-Val-Gly-His-Leuψ(CH 2 NH)、 ― Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH 2 or ― D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH 2 The kit formulation of claim 1, comprising a peptide sequence selected from the group consisting of:

8. 2. The kit formulation of claim 1, wherein the formulation for the preparation of a chelate-functionalized GRP receptor targeting conjugate is labeled with a trivalent radioactive metal cation or a divalent radioactive metal cation.

9. A method for preparing a radiometal-labeled, chelate-functionalized GRP receptor targeting conjugate using the kit formulation according to any one of claims 1 to 8, comprising: - mixing said solution of radioactive metal with a kit formulation according to any one of claims 1 to 8, - optionally adding at least one labeling buffer or a mixture of labeling buffers, and - complexing the chelate-functionalized GRP receptor targeting conjugate according to any one of claims 1 to 8 with a radioactive metal, The method comprising:

10. A radiometal-labeled chelate-functionalized targeting conjugate obtainable by the method of claim 9.

11. A radiopharmaceutical composition comprising the radiometal-labeled chelate-functionalized GRP receptor targeting conjugate of claim 10.

12. - a vial containing a lyophilized kit formulation according to any one of claims 1 to 8, - a vial or syringe containing at least one labelling buffer or a mixture of labelling buffers, and / or - a vial or syringe containing a solution of radioactive metal, Including the kit.