Grpr targeting radiopharmaceuticals and uses thereof

Abstract

This invention relates to radiopharmaceuticals targeting the gastrin-releasing peptide receptor (GRPR) and their uses. Specifically, this invention relates to a pharmaceutical composition comprising a radiolabeled GRPR antagonist and a surfactant. This invention also relates to a radiolabeled GRPR antagonist for the treatment or prevention of cancer.

Description

Radioactive Drugs Targeting GRPR and Their Uses The present invention relates to radioactive drugs targeting gastrin-releasing peptide receptor (GRPR) and their uses. Specifically, the present invention relates to a pharmaceutical composition comprising a radio-labeled GRPR antagonist and a surfactant. The present invention also relates to a radio-labeled GRPR antagonist for treating or preventing cancer. The gastrin-releasing peptide receptor (GRPR), also known as the bombesin receptor subtype 2, is a G protein-coupled receptor expressed in various organs, including those of the gastrointestinal tract and pancreas (Guo M et al. Curr Opin Endocrinol Diabetes Obes. 2015;22:3-8,2; Gonzalez N et al. Curr Opin Enocrinol Diabetes Obes. 2008;15:58-64). After binding of a suitable ligand, GRPR is activated, triggering various physiological processes, such as regulation of exocrine and endocrine (Guo M et al. Curr Opin Endocrinol Diabetes Obes. 2015;22:3-8,2; Gonzalez N et al. Curr Opin Enocrinol Diabetes Obes. 2008;15:58-64). Over the past few decades, GRPR expression has been reported in various cancer types, including prostate cancer and breast cancer (Gugger M and Reubi JC. Gastrin-releasing peptide receptors in non-neoplastic and neoplastic human breast. Am J Pathol. 1999;155:2067-2076; Markwalder R and Reubi JC. Cancer Res.1999;59:1152-1159). Therefore, GRPR has become an attractive target for receptor-mediated tumor imaging and therapy, such as peptide receptor scintigraphy and peptide receptor radionuclide therapy (Gonzalez N et al. Curr Opin Enocrinol Diabetes Obes. 2008;15:58-64). After the successful use of radiolabeled somatostatin peptide analogs for nuclear imaging and therapy in neuroendocrine tumors (Brabander T et al. Front Horm Res.2015;44:73-87; Kwekkeboom DJ and Krenning EP. Hematol Oncol Clin North Am.2016;30:179-191), various radiolabeled GRPR radioligands have been synthesized and studied in preclinical and clinical studies (mainly in prostate cancer patients). Examples of such peptide analogs include AMBA, the Demobesin series, and MP2653 (Yu Z et al. Curr Pharm Des.2013;19:3329-3341; Lantry LE et al. J Nucl Med.2006;47:1144-1152.; Schroeder RP et al. Eur J Nucl Med Mol Imaging.2010;37:1386-1396.; Nock B et al. Eur J Nucl Med Mol Imaging.2003;30:247-258.; Mather SJ et al. Mol Imaging Biol.2014;16:888-895). Recent studies have shown that GRPR antagonists are superior to GRPR agonists (Mansi R et al. Eur J Nucl Med Mol Imaging.2011;38:97-107; Cescato R et al. J Nucl Med.2008;49:318-326). Antagonists generally show higher binding affinity and favorable pharmacokinetics compared to receptor agonists (Ginj M et al. Proc Natl Acad Sci USA.2006;103:16436-16441). In addition, clinical studies of radiolabeled GRPR agonists have reported inappropriate side effects in patients caused by GRPR activation after peptide binding to the receptor (Bodei L et al. [Abstract]. Eur J Nucl Med Mol Imaging.2007;34:S221). In recent years, some GRPR antagonists, such as NeoBOMB1, have been found to be radiolabeled with different radionuclides and potentially used for imaging and for treating cancers expressing GRPR, such as (but not limited to) prostate cancer and breast cancer. However, so far only biodistribution studies have been reported, and no effective treatment regimens or pharmaceutical compositions have been developed. Accordingly, in this context, there is a need to provide pharmaceutical compositions comprising GRPR antagonists that can be administered to patients. In addition, there is also a need to provide effective treatment regimens using GRPR antagonists to patients suffering from cancer. In a first aspect, the present invention relates to a pharmaceutical composition comprising a radiolabeled GRPR antagonist of the formula: MC-S-P wherein: M is a radioactive metal and C is a chelating agent that binds to M; S is an optional spacer covalently linked between C and the N-terminus of P; P is a GRP receptor peptide antagonist of the general formula: Xaa1-Xaa2—Xaa3—Xaa4—Xaa5—Xaa6—Xaa7—Z; Xaa1 is absent or is selected from the group consisting of the amino acid residues Asn, Thr, Phe, 3-(2-thienyl)alanine (Thi), 4-chlorophenylalanine (Cpa), α-naphthylalanine (α-Nal), β-naphthylalanine (β-Nal), 1,2,3,4-tetrahydronorharman-3-carboxylic acid (Tpi), Tyr, 3-iodotyrosine (o-I-Tyr), Trp, and pentafluorophenylalanine (5-F-Phe) (all in the L-isomer or D-isomer form); Xaa2 is Gln, Asn or His; Xaa3 is Trp or 1,2,3,4-tetrahydronorharman-3-carboxylic acid (Tpi); Xaa4 is Ala, Ser or Val; Xaa5 is Val, Ser or Thr; Xaa6 is Gly, sarcosine (Sar), D-Ala or β-Ala; Xaa7 is His or (3-methyl)histidine (3-Me)His; Z is selected from -NHOH, -NHNH2, -NH-alkyl, -N(alkyl)2 and -O-alkyl or Z is wherein X is NH (amide) or O (ester), and R1 and R2 are the same or different and are selected from a proton, an optionally substituted alkyl, an optionally substituted alkyl ether, an aryl, an aryl ether or an alkyl-, a halogen, a hydroxyl or an aryl or heteroaryl substituted with a hydroxyalkyl; and a surfactant comprising a compound having (i) a polyethylene glycol chain and (ii) a fatty acid ester. In a second aspect, the present invention relates to a composition comprising a radiolabeled GRPR antagonist for the treatment or prevention of cancer in an individual, wherein - the radiolabeled GRPR antagonist has the following formula: MC-S-P where: M is a radioactive metal and C is a chelating agent that binds M; S is an optional spacer covalently linked between C and the N-terminus of P; P is a GRP receptor peptide antagonist of the following general formula: Xaa1-Xaa2—Xaa3—Xaa4—Xaa5—Xaa6—Xaa7—Z; Xaa1 is absent or is selected from the group consisting of the amino acid residues Asn, Thr, Phe, 3-(2-thienyl)alanine (Thi), 4-chlorophenylalanine (Cpa), α-naphthylalanine (α-Nal), β-naphthylalanine (β-Nal), 1,2,3,4-tetrahydronorharman-3-carboxylic acid (Tpi), Tyr, 3-iodotyrosine (o-I-Tyr), Trp, and pentafluorophenylalanine (5-F-Phe) (all in the L-isomer or D-isomer form); Xaa2 is Gln, Asn, or His; Xaa3 is Trp or 1,2,3,4-tetrahydronorharman-3-carboxylic acid (Tpi); Xaa4 is Ala, Ser, or Val; Xaa5 is Val, Ser, or Thr; Xaa6 is Gly, sarcosine (Sar), D-Ala, or β-Ala; Xaa7 is His or (3-methyl)histidine (3-Me)His; Z is selected from -NHOH, -NHNH2, -NH-alkyl, -N(alkyl)2, and -O-alkyl or Z is where X is NH (amide) or O (ester), and R1 and R2 are the same or different and are selected from a proton, an optionally substituted alkyl, an optionally substituted alkyl ether, an aryl, an aryl ether, or an alkyl-, a halogen, a hydroxyl, or an aryl or heteroaryl substituted with a hydroxyalkyl; and - the radiolabeled GRPR antagonist is administered to the individual in a therapeutically effective amount between 2000 MBq and 10000 MBq. The defined phrases "treatment of and treating" include alleviating or halting a disease, disorder, or its symptoms. The phrase "prevention of and preventing" includes preventing the onset of a disease, disorder, or its symptoms. According to the International System of Units, "MBq" is an abbreviation for the unit of radioactivity "megabecquerel". As used herein, "PET" refers to positron-emission tomography. As used herein, "SPECT" refers to single-photon emission computed tomography. As used herein, the term "effective amount" or "therapeutically effective amount" of a compound refers to an amount of the compound that will elicit a biological or pharmaceutical response in an individual, such as alleviating symptoms, relieving conditions, slowing or delaying disease progression, or preventing disease. As used herein, the term "substituted" or "optionally substituted" refers to a group optionally substituted with one or more substituents selected from: halogen, -OR', -NR'R'', -SR', -SiR'R''R''', -OC(O)R', -C(O)R', -CO 2 R', -C(O)NR'R'', -OC(O)NR'R'', -NR''C(O)R', -NR'-C(O)NR''R''', -NR''C(O)OR', -NR-C(NR'R''R''')=NR'''', -NR-C(NR'R'')=NR'''-S(O)R', -S(O) 2 R', -S(O) 2 NR'R'', -NRSO 2 R', -CN, -NO 2 , -R', -N 3 , -CH(Ph) 2 , fluoro(C 1 -C 4 )alkoxy and fluoro(C 1 -C 4 )alkyl, wherein the number ranges from zero to the total number of open valences on the aromatic ring system; and wherein R', R'', R''' and R'''' can independently be selected from hydrogen, alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl and heteroaryl. For example, when the compounds of the present invention include more than one R group, when more than one such group is present, each of the R groups is independently selected as each of the R', R'', R''' and R'''' groups. As used herein, the term "alkyl", alone or as part of another substituent, refers to a straight or branched chain alkyl functional group having 1 to 12 carbon atoms. Suitable alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl, pentyl and its isomers (e.g. n-pentyl, isopentyl) and hexyl and its isomers (e.g. n-hexyl, isohexyl). As used herein, the term "heteroaryl" refers to a polyunsaturated aromatic ring system having a single ring or multiple aromatic rings fused together or covalently linked, the aromatic ring system containing 5 to 10 atoms, wherein at least one ring is aromatic and at least one ring atom is a heteroatom selected from N, O and S. The nitrogen heteroatom and sulfur heteroatom may optionally be oxidized and the nitrogen heteroatom may optionally be quaternized. Such rings may be fused to aryl rings, cycloalkyl rings or heterocyclic rings. Non-limiting examples of such heteroaryl groups include: furyl, thienyl, pyrrolyl, pyrazolyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, triazolyl, oxadiazolyl, thiadiazolyl, tetrazolyl, oxatriazolyl, thiatriazolyl, pyridyl, pyrimidinyl, pyrazinyl, pyridazinyl, oxazinyl, dioxinyl, thiazinyl, triazinyl, indolyl, isoindolyl, benzofuryl, isobenzofuryl, benzothienyl, isobenzothienyl, indazolyl, benzimidazolyl, benzoxazolyl, purinyl, benzothiadiazolyl, quinolinyl, isoquinolinyl, phthalazinyl, quinazolinyl and quinoxalinyl. As used herein, the term "aryl" refers to a polyunsaturated aromatic hydrocarbon group having a single ring or multiple aromatic rings fused together, the aromatic hydrocarbon group containing 6 to 10 ring atoms, wherein at least one ring is aromatic. The aromatic ring may optionally contain one or two additional rings fused thereto (cycloalkyl, heterocyclic or heteroaryl as defined herein). Suitable aryl groups include phenyl, naphthyl and benzene rings fused to heterocyclic groups, such as benzopyranyl, benzodioxolyl, benzodioxanyl and similar groups. As used herein, the term "halogen" refers to a fluorine (-F), chlorine (-Cl), bromine (-Br) or iodine (-I) group. As used herein, the term "optionally substituted aliphatic chain" refers to an optionally substituted aliphatic chain having 4 to 36 carbon atoms, preferably 12 to 24 carbon atoms. Radioactive label GRPR Antagonist As used herein, a GRPR antagonist has the following formula: MC-S-P where: M is a radioactive metal and C is a chelating agent that binds to M; S is an optional spacer covalently linked between C and the N-terminus of P; P is a GRP receptor peptide antagonist of the following general formula: Xaa1-Xaa2—Xaa3—Xaa4—Xaa5—Xaa6—Xaa7—Z; Xaa1 is absent or is selected from the group consisting of the amino acid residues Asn, Thr, Phe, 3-(2-thienyl)alanine (Thi), 4-chlorophenylalanine (Cpa), α-naphthylalanine (α-Nal), β-naphthylalanine (β-Nal), 1,2,3,4-tetrahydronorharman-3-carboxylic acid (Tpi), Tyr, 3-iodotyrosine (o-I-Tyr), Trp, and pentafluorophenylalanine (5-F-Phe) (all in the L-isomer or D-isomer form); Xaa2 is Gln, Asn, or His; Xaa3 is Trp or 1,2,3,4-tetrahydronorharman-3-carboxylic acid (Tpi); Xaa4 is Ala, Ser, or Val; Xaa5 is Val, Ser, or Thr; Xaa6 is Gly, sarcosine (Sar), D-Ala, or β-Ala; Xaa7 is His or (3-methyl)histidine (3-Me)His; Z is selected from -NHOH, -NHNH2, -NH-alkyl, -N(alkyl)2, and -O-alkyl or Z is where X is NH (amide) or O (ester), and R1 and R2 are the same or different and are selected from a proton, an optionally substituted alkyl, an optionally substituted alkyl ether, an aryl, an aryl ether, or an alkyl-, a halogen, a hydroxyl, or an aryl or heteroaryl substituted with a hydroxyalkyl. According to one embodiment, Z is selected from one of the following formulas, where X is NH or O: According to one embodiment, the chelating agent C is selected from the group consisting of: In a specific embodiment, C is selected from the group consisting of: According to one embodiment, S is selected from the group consisting of: a) an aryl containing a residue of the following formula: where PABA is p-aminobenzoic acid, PABZA is p-aminobenzylamine, PDA is phenylenediamine, and PAMBZA is (aminomethyl)benzylamine; b) a dicarboxylic acid, ω-aminocarboxylic acid, ω-diaminocarboxylic acid, or diamine having the following formula: where DIG is diglycolic acid and IDA is iminodiacetic acid; c) PEG spacers of various chain lengths, especially PEG spacers selected from the following: n = 1, 2, 3... up to 36, m = 0, 1, 2, 3, 4, 5 d) α - amino acids and β - amino acids, single - chain or homologous chains of various chain lengths or heterologous chains of various chain lengths, especially: GRP(1 - 18), GRP(14 - 18), GRP(13 - 18), BBN(1 - 5) or [Tyr4]BB(1 - 5); or e) combinations of a, b, c and d. According to one embodiment, the GRPR antagonist is selected from the group consisting of compounds of the following formula: where MC and P are as defined above. According to one embodiment, P is DPhe - Gln - Trp - Ala - Val - Gly - His - NH - CH(CH 2 -CH(CH 3 ) 2 ) 2 . According to one embodiment, the radiolabeled GRPR antagonist is the radiolabeled NeoBOMB1 of formula (I): (M - DOTA - (p - aminobenzylamine - diglycolic acid) - [D - Phe 6 , His - NH - CH[(CH 2 -CH(CH 3 ) 2 2 12 , des - Leu 13 , des - Met 14 BBN(6 - 14)); where M is a radioactive metal, preferably M is selected from 177 Lu, 68 Ga and 111 In. According to one embodiment, the radiolabeled GRPR antagonist is the radiolabeled NeoBOMB2 of formula (II): (M - N 4 (p - aminobenzylamine - diglycolic acid)-[D - Phe 6 , His - NH - CH[(CH 2 - CH(CH 3 ) 2 2 12 , des - Leu 13 , des - Met 14 BBN(6 - 14)); wherein M is a radioactive metal. In one embodiment, M is a radioactive metal selected from the following: 111 In, 133m In, 99m Tc, 94m Tc, 67 Ga, 66 Ga, 68 Ga, 52 Fe, 169 Er, 72 As, 97 Ru, 203 Pb, 212 Pb, 62 Cu, 64 Cu, 67 Cu, 186 Re, 188 Re, 86 Y, 90 Y, 51 Cr, 52m Mn, 157 Gd, 177 Lu, 161 Tb, 69 Yb, 175 Yb, 105 Rh, 166 Dy, 166 Ho, 153 Sm, 149 Pm, 151 Pm, 172 Tm, 121 Sn, 117m Sn, 213 Bi, 212 Bi, 142 Pr, 143 Pr, 198 Au, 199 Au, 89 Zr, 225 Ac and 47 Sc. Preferably, M is selected from 177 Lu, 68 Ga and 111 In. According to one embodiment, M is 177 Lu. In this case, the radiolabeled GRPR antagonist can be used in radionuclide therapy. According to another embodiment, M is 68 Ga. In this case, the radiolabeled GRPR antagonist can be used in PET. According to another embodiment, M is 111 In. In this case, the radiolabeled GRPR antagonist can be used for SPECT. The pharmaceutical composition of the GRPR antagonist tends to adhere to glass and plastic surfaces due to non-specific binding (NSB), which is a problem regarding the formulation of pharmaceutical compositions. To provide a stable composition, several surfactants were tested. The inventors unexpectedly found that among all the tested surfactants, the surfactant containing a compound having (i) a polyethylene glycol chain and (ii) a fatty acid ester gave the best results. In a first aspect, the present invention relates to a pharmaceutical composition comprising a radiolabeled GRPR antagonist as described herein and a surfactant, the surfactant comprising a compound having (i) a polyethylene glycol chain and (ii) a fatty acid ester. In one embodiment, the surfactant also comprises free ethylene glycol. In one embodiment, the surfactant comprises a compound of formula (III) where n is between 3 and 1000, preferably between 5 and 500, and more preferably between 10 and 50, and R is a fatty acid chain, preferably an optionally substituted aliphatic chain. In one embodiment, the surfactant comprises polyethylene glycol 15-hydroxystearate and free ethylene glycol. The radiolabeled GRPR antagonist can be present at a concentration providing a volume radioactivity of at least 100 MBq / mL, preferably at least 250 MBq / mL. The radiolabeled GRPR antagonist can be present at a concentration providing a volume radioactivity between 100 MBq / mL and 1000 MBq / mL, preferably between 250 MBq / mL and 500 MBq / mL. The surfactant can be present at a concentration of at least 5 µg / mL, preferably at least 25 µg / mL and more preferably at least 50 µg / mL. The surfactant can be present at a concentration between 5 µg / mL and 5000 µg / mL, preferably between 25 µg / mL and 2000 µg / mL, and more preferably between 50 µg / mL and 1000 µg / mL. In one embodiment, the composition comprises at least one other pharmaceutically acceptable excipient. The pharmaceutically acceptable excipient can be any of the excipients conventionally used and is limited only by physicochemical considerations such as solubility and lack of reactivity towards the active compound. Specifically, one or more excipients can be selected from stabilizers against radiolysis, buffers, chelating agents, and mixtures thereof. As used herein, "radiolysis stabilizer" refers to a stabilizer that protects organic molecules from radiolysis. For example, when γ-rays emitted from a radionuclide cleave the interatomic bonds of an organic molecule and free radicals are formed, those free radicals are subsequently scavenged by the stabilizer, which prevents the free radicals from undergoing any other chemical reactions that may lead to undesired, potentially ineffective, or even toxic molecules. Thus, those stabilizers are also referred to as "radical scavengers" or simply "free radical scavengers". Other alternative terms for those stabilizers are "radiation stability enhancer", "radiolysis stabilizer", or simply "inhibitor". As used herein, "chelating agent" refers to a chelating agent suitable for complexing free radioactive nuclide metal ions in a formulation (which does not complex with the radiolabeled peptide). Buffers include acetate buffer, citrate buffer, and phosphate buffer. According to one embodiment, the pharmaceutical composition is an aqueous solution, such as an injectable formulation. According to a specific embodiment, the pharmaceutical composition is an infusion solution. The requirements for an effective pharmaceutical carrier for an injectable composition are well known to those of ordinary skill in the art (see, for example, Pharmaceutics and Pharmacy Practice, J.B. Lippincott Company, Philadelphia, PA, edited by Banker and Chalmers, pages 238-250 (1982), and ^SHP Handbook on Injectable Drugs, Trissel, 15th edition, pages 622-630 (2009)). The present invention also relates to a method of manufacturing a pharmaceutical composition, which comprises combining a radiolabeled GRPR antagonist with a surfactant. The present invention also relates to the pharmaceutical composition as described above, which is used for treating or preventing cancer. As used herein, the term "cancer" refers to cells having the ability of autonomous growth (i.e., an abnormal condition or disorder characterized by rapid proliferative cell growth). Hyperplastic and neoplastic disease conditions can be classified as pathological, i.e., characterizing or constituting a disease condition, or can be classified as non-pathological, i.e., a deviation from normal but not associated with a disease condition. The term is intended to include all types of neoplastic growth or carcinogenic processes, metastatic tissues, or malignantly transformed cells, tissues, or organs (regardless of histopathologic type or stage of invasion). In certain embodiments, the cancer is selected from prostate cancer, breast cancer, small cell lung cancer, colon cancer, gastrointestinal stromal tumor, gastrinoma, renal cell carcinoma, gastroenteropancreatic neuroendocrine tumor, esophageal squamous cell tumor, neuroblastoma, head and neck squamous cell carcinoma, and ovarian, endometrial, and pancreatic tumors exhibiting neoplasm-associated vascular structures, which are GRPR. In one embodiment, the cancer is prostate cancer or breast cancer. The present invention also relates to a pharmaceutical composition as described above for in vivo imaging, particularly for detecting GRPR-positive tumors in an individual in need thereof, preferably by PET and SPECT imaging. The present invention also relates to a method for treating or preventing cancer in an individual in need thereof, the method comprising administering to the individual a therapeutically effective amount of a pharmaceutical composition as described above. The present invention also relates to a method for in vivo imaging, the method comprising administering to an individual an effective amount of a pharmaceutical composition as described above and detecting a signal derived from the decay of a radioisotope present in the compound. Radioactive labeling for treating cancer GRPR In a second aspect, the present invention also relates to a composition comprising a radiolabeled GRPR antagonist for treating or preventing cancer in an individual in need thereof, wherein the radiolabeled GRPR antagonist is administered to the individual in a therapeutically effective amount between 2000 MBq and 10000 MBq. In certain embodiments, the therapeutically effective amount of the composition is administered to the individual 2 to 8 times per treatment. For example, a patient may be treated with a radiolabeled GRPR antagonist, specifically 177 Lu-NeoBOMB1, each at 2000 MBq to 10000 MBq, by intravenous treatment for 2 to 8 cycles. In certain aspects, the individual is a mammal, such as (but not limited to) a rodent, dog, cat, or primate. In certain aspects, the individual is a human. The inventors have found that 177 Lu-NeoBOMB1 is effective, as shown in animal models of cancer. Compared to untreated animals, the treatment group had a significantly longer tumor growth delay time and a significantly longer median survival time. In the non-limiting examples described herein, animals were treated with 3×30 MBq / 300 pmol, 3×40 MBq / 400 pmol, or 3×60 MBq / 600 pmol 177Lu-NeoBOMB1 treatment. No significant differences in tumor growth delay time and median survival were found between the treatment groups. This finding was unexpected because previous dosimetry calculations using the linear quadratic model predicted differences in tumor control probability between the treatment groups (tumor control probabilities: 0%, 75%, and 100% for animals treated with 3×30 MBq / 300 pmol, 3×40 MBq / 400 pmol, and 3×60 MBq / 600 pmol, respectively). Without being bound by any theory, it is predicted that the dose required to treat patients will be much lower than expected from previous dosimetry calculations, which will result in lower toxicity of radiolabeled NeoBOMB1. Advantageously, the radiolabeled GRPR antagonist is labeled with 177 Lu. In a specific embodiment of the above method, the cancer is selected from prostate cancer, breast cancer, small cell lung cancer, colon cancer, gastrointestinal stromal tumor, gastrinoma, renal cell carcinoma, gastroenteropancreatic neuroendocrine tumor, esophageal squamous cell tumor, neuroblastoma, head and neck squamous cell carcinoma, and ovarian, endometrial, and pancreatic tumors presenting tumor-associated vascular structures, which are GRPR-positive. In one embodiment, the cancer is prostate cancer or breast cancer. According to one embodiment, the composition used is the pharmaceutical composition as described in the previous section. The present invention also relates to a method of treating or preventing cancer, the method comprising administering to an individual suffering from cancer an effective amount of a composition comprising a radiolabeled GRPR antagonist, wherein the radiolabeled GRPR antagonist is administered to the individual in a therapeutically effective amount between 2000 MBq and 10000 MBq. A method of treating or preventing cancer is provided herein, the method comprising administering to an individual suffering from cancer an effective amount of a composition comprising a radiolabeled GRPR antagonist as disclosed herein. In certain aspects, the cancer is prostate cancer or breast cancer. In certain aspects, administering a composition comprising a radiolabeled GRPR antagonist to an individual with cancer can inhibit, delay, and / or reduce tumor growth in the individual. In certain aspects, tumor growth is delayed by at least 50%, 60%, 70%, or 80% compared to untreated control individuals. In certain aspects, tumor growth is delayed by at least 80% compared to untreated control individuals. In certain aspects, tumor growth is delayed by at least 50%, 60%, 70%, or 80% compared to the predicted growth of an untreated tumor. In certain aspects, tumor growth is delayed by at least 80% compared to the predicted growth of an untreated tumor. One of ordinary skill in the art will recognize that tumor growth rate predictions are made based on epidemiological data, reports in the medical literature, and other knowledge in the field, measurements of tumor type and tumor size, etc. In certain aspects, administering a composition comprising a radiolabeled GRPR antagonist to an individual with cancer can increase the survival time of the individual. In certain aspects, the increase in survival rate is compared to untreated control individuals. In certain aspects, the increase in survival rate is compared to the predicted survival time of untreated individuals. In certain aspects, the survival time is increased by at least 3-fold, 4-fold, or 5-fold compared to the time of untreated control individuals. In certain aspects, the survival time is increased by at least 4-fold compared to the time of untreated control individuals. In certain aspects, the survival time is increased by at least 3-fold, 4-fold, or 5-fold compared to the predicted survival time of untreated individuals. In certain aspects, the survival time is increased by at least 4-fold compared to the predicted survival time of untreated individuals. In certain aspects, the survival time is increased by at least one week, two weeks, one month, two months, three months, six months, one year, two years, or three years compared to untreated control individuals. In certain aspects, the survival time is increased by at least one month, two months, or three months compared to untreated control individuals. In certain aspects, the survival time is increased by at least one week, two weeks, one month, two months, three months, six months, one year, two years, or three years compared to the predicted survival time of untreated individuals. In certain aspects, the survival time is increased by at least one month, two months, or three months compared to the predicted survival time of untreated individuals. In certain aspects, the amount of radiolabeled GRPR antagonist administered is less than the amount predicted to have a 100% probability of tumor control in the individual. In certain aspects, the amount of the radiolabeled GRPR antagonist administered is less than the amount predicted for an individual to have a 75% probability of tumor control in that individual. In certain aspects, the amount of the radiolabeled GRPR antagonist administered is less than the amount predicted for an individual to achieve a 50% probability of tumor control in that individual. In certain aspects, the amount of the radiolabeled GRPR antagonist administered is less than the amount predicted for an individual to achieve a 25% probability of tumor control in that individual. In certain aspects, the amount of the radiolabeled GRPR antagonist administered is less than the amount predicted for an individual to achieve a 10% probability of tumor control in that individual. In certain aspects, the amount of the radiolabeled GRPR antagonist administered does not exceed 25%, 30%, 40%, 50%, 60%, 70%, or 75% of the amount predicted for an individual to achieve a 100% probability of tumor control in that individual. In certain aspects, the amount of the radiolabeled GRPR antagonist administered does not exceed 50%, 60%, 70%, 75%, 80%, or 85% of the amount predicted for an individual to achieve a 75% probability of tumor control in that individual. In certain aspects, the amount of the radiolabeled GRPR antagonist administered does not exceed 60%, 65%, 70%, 75%, 80%, 85%, or 90% of the amount predicted for an individual to achieve a 50% probability of tumor control in that individual. In certain aspects, the amount of the radiolabeled GRPR antagonist administered is an amount predicted for an individual to have a less than 25%, 20%, 15%, 10%, or 5% probability of tumor control. In certain aspects, the amount of the radiolabeled GRPR antagonist administered is an amount predicted for an individual to have a 0% probability of tumor control. In certain aspects, the amount of the radiolabeled GRPR antagonist administered is an amount predicted for an individual to have a 0% probability of tumor control. Example Example 1 : Use 68 Ga - NeoBOMB1 Screen formulations to reduce NeoBOMB1 Adhesion During the development of the formulation kit, we realized that the peptide has a specific tendency to adhere to glass and plastic surfaces. This phenomenon is called non-specific binding (NSB). Peptides generally exhibit greater NSB problems compared to small molecules, especially uncharged peptides which can strongly adsorb to plastics. The reasons can vary: physical / chemical properties, Van der Waals interactions, ionic interactions. Organic solvents can enhance solubility and prevent adsorption. Ethanol, for example, can be used in radiopharmaceutical injections to increase the solubility of highly lipophilic tracers or reduce adsorption to vials, membrane filters, and injection syringes. We discarded ethanol because it is incompatible with lyophilization. Human serum albumin (HSA) is also used as a stabilizer in various protein formulations to prevent surface adsorption, but this excipient is not suitable due to its thermal instability. Another viable method is to use surfactants (such as polysorbate 20, polysorbate 80, Pluronic F-68, sorbitan trioleate). We focused on the study of non-ionic surfactants because ionic surfactants can interfere with 68 the labeling of Ga. Non-ionic surfactants, such as Kolliphor HS 15, Kolliphor K188, Tween 20, Tween 80, polyvinylpyrrolidone K10, are commercially available as solubilizing excipients in oral and injectable formulations. In the following table, the initial tests conducted with different surfactants are outlined. Materials and Methods : The labeling of NeoBOMB1 is based on the kit method previously published by Castaldi et al. (Castaldi E, Muzio V, D'Angeli L, Fugazza L. 68 GaDOTATATE lyophilized ready to use kit for PET imaging in pancreatic cancer murine model, J Nucl Med2014; 55(suppl 1):1926). Different surfactants were screened and the adhesion % of the resulting aqueous solutions was measured by a dose calibrator to determine the radioactivity retained in the vial after complete drainage of the radiolabeled solution. The difference in radioactivity measured before and after sample drainage (expressed as a percentage) is directly related to the adhesion of the peptide to the container closure system. The results are outlined in Table 1. Table 1 - Surfactant - Adhesion Optimal results regarding peptide adhesion were obtained with Kolliphor HS 15 and Tween 20. Two excipients were further studied to determine the final amounts in the kit. The results obtained were good in terms of radiochemical purity and peptide adhesion. Table 2 - Comparison between Tween 20 and Kolliphor HS 15 We focused on Kolliphor HS 15 because polysorbate (Tween 20) can undergo auto - oxidation, cleavage at the ethylene oxide sub - unit, and hydrolysis of the fatty acid ester bond caused by the presence of oxygen, metal ions, peroxides, or high temperature. Example 2: For 177 Pre - clinical study of the therapeutic efficacy of Lu - NeoBOMB1 This article discloses a pre - clinical study 177 Exemplary, non - limiting examples of the therapeutic efficacy of Lu - NeoBOMB1, which involve treating xenograft animals with three different doses of 177 Lu - NeoBOMB1 that bear the well - known GRPR prostate cancer cell line PC - 3. Additionally, in a group of small non - tumor - bearing animals, the effects of Lu - NeoBOMB1 treatment on the kidneys and pancreas were studied by histopathological examination after treatment 177 Lu - NeoBOMB1 treatment on the kidneys and pancreas. Materials and methods Radio - labeling NeoBOMB1 (ADVANCED ACCELERATOR APPLICATIONS) (WO2014052471) was diluted in ultrapure water, and the concentration and chemical purity were monitored using a self - developed titration method. (Breeman WA, de Zanger RM, Chan HS, de Blois E. Alternative method to determine specific activity of 177 Lu by HPLC. Curr Radiopharm. 2015; 8:119 - 122). Radioactivity (100 MBq / nmol) was added to vials containing all the necessary excipients (such as buffers, antioxidants, and peptides, including the surfactant (Kolliphor HS15)) 177Lu) to prevent peptide adhesion. High performance liquid chromatography was performed with a gradient of methanol and 0.1% trifluoroacetic acid to determine radiochemical purity. As previously described, radiometal incorporation measured by instant thin layer chromatography on silica gel (de Blois E, Chan HS, Konijnenberg M, de Zanger R, Breeman WA. Effectiveness of quenchers to reduce radiolysis of (111)In- or ( 177 )Lu-labelled methionine-containing regulatory peptides. Maintaining radiochemical purity as measured by HPLC. Curr Top Med Chem. 2012;12:2677-2685), was >67% and >90% for SPECT / CT and efficacy and toxicity studies, respectively. Animal models, efficacy, and toxicity All animal studies were in accordance with the requirements of the Animal Welfare Committee of the Erasmus Medical Center and were conducted according to recognized guidelines. Male balb c nu / nu mice were subcutaneously inoculated in the right shoulder with 200 µL of 4×10 6 PC-3 cells (American Type Culture Collection) in inoculation medium (1 / 3 Matrigel high concentration (Corning) + 2 / 3 Hank's balanced salt solution (Thermofisher Scientific)). Four weeks after tumor cell inoculation, when the average tumor size reached 543 ± 177 mm 3 , the animals were divided into four groups: a control group (n = 10) and treatment groups 1-3 (n = 15 / group). To determine the 177 efficacy of Lu-NeoBOMB1, the animals were anesthetized with isoflurane / O 2 and received 3 sham injections (control group), 3 × 30 MBq / 300 pmol 177Lu-NeoBOMB1 (Group 1), 3 × 40 MBq / 400 pmol 177 Lu-NeoBOMB1 (Group 2) or 3 × 60 MBq / 600 pmol 177 Lu-NeoBOMB1 (Group 3). The injection solution was administered intravenously, and the injection solution was given at 1-week intervals. To determine the effect of the treatment on pancreatic and renal tissues, non-tumor-bearing balb c nu / nu male mice received the same treatment as the animals included in the efficacy study. At two different time points after the last therapeutic injection (12 weeks and 24 weeks after inoculation), the animals were euthanized and pancreatic and renal tissues were collected for pathological analysis. In both studies, the animal weight and / or tumor size were measured every two weeks. When the tumor size was ≥2000 mm 3 or when the animal weight decreased by ≥20% within 48 hours, the animals were removed from the study. In the efficacy study, the animals were followed until the maximum allowed age of 230 days was reached. SPECT / CT For tumor uptake quantification, SPECT / CT imaging was performed in other groups of PC-3 xenograft animals (n = 2 animals / group). When the tumor size was 477 ± 57 mm 3At that time, the animals were injected with the same amount of peptide as the animals included in the efficacy and toxicity studies. At 4 hours and 24 hours after the first therapeutic agent injection, and at 4 hours after the second and third therapeutic agent injections, whole-body SPECT / CT scans were performed on a combined SPECT / CT scanner (VECTor5, MILabs, Utrecht, The Netherlands). SPECT was performed on 40 bed positions in 30 minutes using a 2.0 mm pinhole collimator with a reported spatial resolution of 0.85 mm (Ivashchenko O, van der Have F, Goorden MC, Ramakers RM, Beekman FJ. Ultra-high-sensitivity submillimeter mouse SPECT. J Nucl Med. 2015;56:470-475). SPECT images were reconstructed using 113 and 208 keV photopeak windows and the SR-OSEM reconstruction method, with background windows having a corresponding photopeak width of 20% on either side of the photopeak, (Vaissier PE, Beekman FJ, Goorden MC. Similarity-regulation of OS-EM for accelerated SPECT reconstruction. Phys Med Biol. 2016;61:4300-4315), and a voxel size of 0.8 mm 3 , and registered to the CT data. A 3D Gaussian filter (1 mm fwhm) was applied for post-reconstruction. CT was performed with the following settings: 0.24 mA, 50 kV, full-angle scan, 1 position. CT was reconstructed at 100 µm 3 reconstruction. Pathological analysis The pancreas and kidney tissues collected for pathological analysis were fixed in formalin and embedded in paraffin. Hematoxylin and eosin staining was performed on 4 µm thick tissue sections using the Ventana Symphony™ H&E protocol (Ventana) to determine the tissue structure differences between the 4 treatment groups. In a total of 4 tissue sections, each organ was evaluated at intervals of 50 µm from each other. Hematoxylin and eosin stained tissues were evaluated by experienced pathologists. Dose measurements were performed using a 25 g RADAR realistic mouse model (Keenan MA, Stabin MG, Segars WP, Fernald MJ. RADAR realistic animal model series for dose assessment. J Nucl Med. 2010;51:471-476) and data from previously published biodistribution and pharmacokinetic studies (Dalm SU, Bakker IL, de Blois E et al. 68Ga / 177 Lu-NeoBOMB1, a Novel Radiolabeled GRPR Antagonist for Theranostic Use in Oncology. J Nucl Med. 2017;58:293-299) to calculate the doses to the tumor, pancreas, and kidneys, where the animals were treated with 3×30 MBq / 300 pmol, 4×40 MBq / 400 pmol, or 3×60 MBq / 600 pmol 177 of Lu-NeoBOMB1. The biodistribution data from our previously published paper (Dalm SU, Bakker IL, de Blois E et al. 68 Ga / 177 Lu-NeoBOMB1, a Novel Radiolabeled GRPR Antagonist for Theranostic Use in Oncology. J Nucl Med. 2017;58:293-299) were fitted to exponential curves to determine the time-activity curves in the tumor and organs. 177 The time-integrated activity of Lu was determined by integrating these exponential curves that overlapped with the 177 decay curve of Lu (T 1 / 2=6.647 d) was obtained. For a 340 mg tumor, the absorbed dose per administered activity was obtained by multiplying with the organ S values from Keenan et al. (Keenan MA, Stabin MG, Segars WP, Fernald MJ. RADAR realistic animal model series for dose assessment. J Nucl Med. 2010;51:471-476) or by using the spherical node S values (Stabin MG, Konijnenberg MW. Re-evaluation of absorbed fractions for photons and electrons in spheres of various sizes. J Nucl Med. 2000;41:149-160). Tumor dosimetry was used to predict treatment outcome by using a linear quadratic (LQ) model based on the tumor control probability (TCP). (Konijnenberg MW, Breeman WA, de Blois E et al. Therapeutic application of CCK2R-targeting PP-F11: influence of particle range, activity and peptide amount. EJNMMI Res. 2014;4:47). By N clonogens , the number of the core population of cells (stem cells) within the tumor and the S ( D , T) cell survival fraction vary with the absorbed dose D and time T. The LQ model indicates that the survival fraction varies with the absorbed dose for tumor growth with a doubling time T d as follows: where α is the radiation sensitivity of the tumor, α / β is the ratio between direct (α) and indirect (β) radiation sensitivities, and G is the time factor representing the accumulation of indirect damage during dose delivery, determined by the effective decay half-life and the half-life of sublethal damage repair. The tumor doubling time is determined by fitting an exponential growth function to the tumor volume over time in the control group. The radiation sensitivity parameters of the PC-3 tumor were obtained from LDR and HDR brachytherapy survival data: α = 0.145 Gy and α / β = 4.1 (2.5 to 5.7) Gy (Carlson D, Stewart RD, Li XA, Jennings K, Wang JZ, Guerrero M. Comparison of in vitro and in vivo alpha / beta ratios for prostate cancer. Phys Med Biol. 2004;49:4477-4491). The half-life of sublethal damage repair for the PC-3 tumor was indicated as: 6.6 (5.3 - 8.0) h (Carlson DJ, Stewart RD, Li XA, Jennings K, Wang JZ, Guerrero M. Comparison of in vitro and in vivo alpha / beta ratios for prostate cancer. Phys Med Biol. 2004;49:4477-4491), but this value was conservatively fixed at the lower value of 1 h (Joiner M, Kogel Avd. Basic clinical radiobiology. 4th ed London: Hodder Arnold; 2009). The TCP model was used to select the administration activities that would only cause growth delay (TCP = 0%), partial response (TCP > 75%), and complete response (TCP = 100%). It was assumed that the density of the clonogenic cell population in the PC-3 tumor xenograft was 10 6 cells / cm 3 . Tumor volume analysis determined the tumor doubling time by fitting an exponential growth function to the tumor volume over time in the control group. In the therapy group, the time interval with exponential tumor volume regression was fitted to the start of regeneration after the nadir time. For tumors with excessive size (> 2000 mm 3For the mice, the growth curve was extrapolated beyond the examination time points to determine the mean growth statistics. By comparing the time required to reach a maximum tumor size of 2000 mm 3 with the mean time found in the control group, the tumor growth delay time was determined separately. Prism software (version 5.01, GraphPad Software) was used for statistical analysis. P values > 0.05 were considered statistically significant. The differences in tumor volume growth and delay time among the 4 groups were analyzed by one-way ANOVA test with Bonferroni's multiple comparison test. According to the minimum / square and Pearson R 2 fitting, curve fitting was performed to quantify the goodness of fit. Results At most time points, the mean radioactivity capture quantified on SPECT / CT was highest for group 3, followed by group 2 and then group 1. However, the differences among these groups were not significant. Figure 1A shows the scans of one animal in each group obtained 4 hours and 24 hours after the first injection and 4 hours after the second and third injections. The quantified tumor captures are depicted in Figure 1B. 177 Lu - NeoBOMB1 The therapeutic efficacy was evaluated using 177 The therapy with Lu-NeoBOMB1 was proven to be effective. The animals in the control group reached a tumor size of 2000 mm within 20.3 ± 5.9 d 3 while for groups 1, 2 and 3, these were 97 ± 59 d, 103 ± 66 d and 95 ± 26 d, respectively (Figure 2A). Additionally, two animals from group 1 and one animal from group 2 did not show any tumor regrowth after complete response. However, there was no significant difference in tumor growth delay time within the treatment groups, while the difference in the control group was very significant (P < 0.0001). Consistent with the above, the animals in the treatment groups had significantly better survival rates compared to the control group (P < 0.001) (Figure 2B). The median survival times for the control group, group 1, group 2 and group 3 were 19 d, 82 d, 89 d and 99 d, respectively. Five animals were excluded from the study (n = 3 from group 2 and n = 2 from group 3) for the following reasons: one animal was found dead after the first injection; one animal had a very small tumor at the start of the therapy, which disappeared within a few days, one animal had a weight loss of more than 10% within 48 hours and one animal retained fluid in the abdominal area. There was no sign of any of the mentioned events being related to the treatment. Kidney and pancreas toxicity The animals included in the toxicity study showed no significant weight loss over the entire follow-up period (Figure 3). The animal weight increased in the first week and remained relatively stable over time. One animal in the control group (ID: B) and one animal in group 1 (ID: 869) showed weight loss, but this was less than 10% within 48 hours. Histopathological analysis of the pancreas showed no tissue damage or other abnormalities (Figure 4). Regarding the kidneys (Figure 5), small areas with lymphocyte infiltration were observed in the kidneys at 12 and 24 weeks after the last therapeutic injection. This was the case for the kidneys of both control animals and treated animals, indicating that this finding was not related to the therapy. At 24 weeks after the therapy, atrophy and fibrosis were observed only in the kidneys of one animal receiving the lowest treatment dose (ID: 864), which was unlikely to be related to the therapy. At 24 weeks after the therapy, a mild chronic inflammatory reaction was observed in the kidneys of two euthanized animals from group 3. Dosimetry After treatment with 3 × 30 MBq / 300 pmol, 3 × 40 MBq / 400 pmol or 3 × 60 MBq / 600 pmol 177 Lu-NeoBOMB1, the radiation doses to the tumor, pancreas and kidneys were estimated (see Table 3 below). For this, it was assumed that the tumor and organ uptake was similar after each injection. Table 3 . Estimated doses to the tumor, pancreas and kidneys when treating animals with 3 × 30 MBq / 300 pmol, 3 × 40 MBq / 400 pmol or 3 × 60 MBq / 600 pmol 177 Estimated doses to the tumor, pancreas and kidneys when treating animals with Lu-NeoBOMB1* Figure 1A. Figure 1A shows SPECT / CT images at 4 and 24 hours after the first injection and at 4 hours after the second and third injections. The arrows indicate the tumor. Animals were injected with 30 MBq / 300 pmol (group 1), 40 MBq / 400 pmol (group 2) or 60 MBq / 600 pmol 177Lu-NeoBOMB1. Figure 1B . Figure 1B shows the quantitative tumor capture from the injection described in Figure 1A (n = 2 animals / group). Figure 2A , Figure 2B . Figure 2A shows the extrapolated tumor sizes of untreated animals and animals treated with 3 × 30 MBq / 300 pmol (Group 1), 3 × 40 MBq / 400 pmol (Group 2), and 3 × 60 MBq / 600 pmol 177 Lu-NeoBOMB1 (Group 3). Figure 2B shows the survival rates of untreated animals and animals treated with 3 × 30 MBq / 300 pmol (Group 1), 3 × 40 MBq / 400 pmol (Group 2), and 3 × 60 MBq / 600 pmol 177 Lu-NeoBOMB1 (Group 3). Figure 3A , Figure 3B . Figure 3A shows the weights of the animals before and after treatment and up to 12 weeks later. Figure 3B shows the weights of the animals before and after treatment and up to 24 weeks later. Figure 4 . Figure 4 shows the representative hematoxylin and eosin staining of pancreatic tissues of untreated and treated animals (3 × 30 MBq / 300 pmol (Group 1), 3 × 40 MBq / 400 pmol (Group 2), and 3 × 60 MBq / 600 pmol 177 Lu-NeoBOMB1 (Group 3)). Figure 5 . Figure 5 shows the representative hematoxylin and eosin staining of pancreatic tissues of untreated and treated animals (3 × 30 MBq / 300 pmol (Group 1), 3 × 40 MBq / 400 pmol (Group 2), and 3 × 60 MBq / 600 pmol 177Representative hematoxylin and eosin staining of kidney tissues of animals in Lu-NeoBOMB1 (Group 3). The circled areas indicate lesions of lymphocyte infiltration (IDs: D, 814, 861, 868, and 862) or atrophy and fibrosis (ID: 864).

Claims

1. A pharmaceutical composition comprising a radiolabeled GRPR antagonist, a surfactant comprising polyethylene glycol 15-hydroxystearate or polyoxyethylene (20) sorbitan monolaurate, and a stabilizer against radiodegradation; wherein the radiolabeled GRPR antagonist is a compound of formula (I): (I), wherein M is a radioactive metal.

2. The pharmaceutical composition of claim 1, wherein M is selected from 177Lu and 68Ga.

3. The pharmaceutical composition of claim 1, wherein M is 177Lu.

4. The pharmaceutical composition of claim 1, wherein the surfactant comprises a compound of formula (III): wherein n is between 3 and 1000, and R is 15-hydroxystearate.

5. The pharmaceutical composition of claim 1, wherein the surfactant comprises polyethylene glycol 15-hydroxystearate.

6. The pharmaceutical composition of claim 1, wherein the radiolabeled GRPR antagonist is present at a concentration providing volumetric radioactivity between 250 MBq / mL and 500 MBq / mL.

7. The pharmaceutical composition of claim 1, wherein the surfactant is present at a concentration of at least 5 µg / mL.

8. The pharmaceutical composition of claim 1, wherein M is selected from 177Lu, 68Ga and 111In.

9. The pharmaceutical composition of claim 1, wherein the pharmaceutical composition is an aqueous solution.

10. The pharmaceutical composition of claim 1, wherein the pharmaceutical composition is an infusion solution.

11. The pharmaceutical composition of claim 1, used for the treatment or prevention of cancer.

12. The pharmaceutical composition of claim 1, used for in vivo imaging.

13. Use of a composition as claimed in claim 1 for manufacturing a medicament for treating or preventing cancer in an individual in need.

14. Use of a composition as claimed in claim 1 for manufacturing a medicament for imaging GRPR-positive tumors in vivo in individuals of need.

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