Novel radiometal-binding compounds for diagnosis or treatment of cancers expressing prostate-specific membrane antigen

Abstract

The present application relates to a compound of formula I-a or formula I-b, or a salt or solvate thereof. 1 Yes‑(CH 2 ) 5 CH 3 Or contain 2‑4 fused benzene rings. 2 Is I, Br, F, Cl, H, OH, OCH 3 NH 2 、NO 2 or CH 3 . R 3 is a peptide-bound glycine, aspartate, or glutamate, or is delta Glutamic acid peptide bound. L is ‑CH 2 NH-,-(CH 2 ) 2 NH-,-(CH 2 ) 3 NH‑or‑(CH 2 ) 4 NH-R 4 is a radiometal chelator, optionally conjugated to a radiometal. The variable "n" is 1-3. The compound can be used to image tissue expressing prostate specific membrane antigen (PSMA) or to treat diseases expressing PSMA (such as cancer).

Description

Technical Field

[0001] The present invention relates to radiolabeled compounds for selective imaging or treatment of cancer, in particular prostate specific membrane antigen targeting compounds. Background Art

[0002] Prostate-specific membrane antigen (PSMA) is a transmembrane protein that catalyzes the hydrolysis of N-acetyl-aspartylglutamate into glutamate and N-acetylaspartate. 1 PSMA is not expressed in most normal tissues but is overexpressed (up to 1000-fold) in prostate tumors and metastases. 2-3 Based on its pathological expression pattern, a variety of radiolabeled PSMA-targeting constructs have been designed and evaluated for internal radiation therapy of prostate cancer. 4-7

[0003] Common radiolabeled PSMA-targeted internal radiotherapy agents are lysine-urea-glutamate (Lys-urea-Glu) derivatives, including 131 I-MIP-1095, 177 Lu-PSMA-617 and 177 Lu-PSMA I&T. 5-7 in, 177 Lu-PSMA-617 is the most studied agent and is currently being evaluated in multicenter trials. 7-14 Preliminary data indicate that 177 Lu-PSMA-617 is effective in treating metastatic prostate cancer, with 32-60% of patients experiencing a greater than 50% reduction in PSA levels and no serious side effects. 7-13 In a phase II study conducted in Australia, objective responses were observed in 82% of patients with measurable nodal or visceral disease. 14 However, the complete remission rate is low (<7%) and 177 After Lu-PSMA-617 treatment, up to 33% of patients still had progressive disease. 7，9-13 Interestingly, recent reports have shown that in patients with advanced metastatic prostate cancer, 225 Ac-PSMA-617 (with α-emitter 225 Ac instead 177 Lu) had impressive efficacy, including one subject whose disease 177 Progression occurred despite Lu-PSMA-617 treatment. 15

[0004] although 225 Ac-PSMA-617 has great potential in internal radiotherapy, but 225The supply of Ac is limited worldwide. 225 Compared with Ac-PSMA-617, it is more effective 177 Lu-labeled PSMA-targeted agents have a greater direct impact on internal radiotherapy of prostate cancer because they comply with good manufacturing practice (GMP) 177 Lu is available in large quantities from a number of suppliers. 225 The greater efficacy of Ac-PSMA-617 may be due to the high linear energy transfer of α-particles, which leads to double-strand breaks, compared with 177 Compared with the indirect damage caused by β-particles emitted by Lu, double-strand breaks make it less susceptible to radiation resistance. One way to improve the effectiveness of radiotherapy is to increase the amount of radioactivity per unit of administered radioactivity. 177 Lu-labeled agents can reduce the radiation dose deposited in tumors. By reducing the cost of radioisotopes, 177 Delivery of Lu to tumors could also reduce the cost of therapeutic radiopharmaceuticals.

[0005] None of the foregoing information is intended or should be construed as constituting prior art to the present invention. Summary of the invention

[0006] Disclosed herein are novel compounds that target PSMA.

[0007] The present disclosure provides a compound of Formula Ia or Formula Ib, or a salt or solvate of Formula Ia or Formula Ib:

[0008]

[0009] in:

[0010] R 1 yes or -(CH 2 ) 5 CH 3 ;

[0011] R 2 Is I, Br, F, Cl, H, OH, OCH 3 , NH 2 , NO 2 or CH 3 ;

[0012] R 3 yes

[0013] L is -CH 2 NH-, -(CH 2 ) 2 NH-, -(CH 2 ) 3 NH-, or -(CH2 ) 4 NH-;

[0014] R 4 is a radiometal chelator, optionally combined with a radiometal X; and n is 1-3.

[0015] Also disclosed are compounds having Formula II or salts or solvates of Formula II:

[0016]

[0017] Where: R 2 is I, Br or methyl; n is 1-3; X is absent, 225 Ac or 177 Lu.

[0018] In some embodiments, when X is a diagnostic radiometal (e.g., suitable for imaging but not necessarily limited to 64 Cu, 111 In, 89 Zr, 44 Sc, 68 Ga, 99m Tc, 86 Y. 152 Tb or 155 Tb), these compounds can be used to image PSMA-expressing cancer in a subject. Therefore, a method of imaging PSMA-expressing cancer in a subject is also disclosed, the method comprising: administering to the subject a composition comprising the compound and a pharmaceutically acceptable excipient; and imaging tissue in the subject.

[0019] In some embodiments, when X is a therapeutic radiometal (e.g., a toxic radiometal, but not limited to 64 Cu, 67 Cu, 90 Y. 111 In, 114分钟 , 117m Sn, 153 Sm, 149 Tb, 161 Tb, 177 Lu, 225 Ac, 213 Bi, 224 Ra, 212 Bi, 212 Pb, 225 Ac, 227 Th, 223 Ra, 47 Sc, 186 Re or 188Re), such compounds can be used to treat cancer expressing PSMA in a subject. Therefore, a method of treating cancer expressing prostate-specific membrane antigen (PSMA) in a subject is also disclosed, the method comprising: administering to the subject a composition comprising the compound and a pharmaceutically acceptable excipient.

[0020] This summary of the invention may not describe all features of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] To elaborate on the above and other features of the present invention, the following will describe them in detail, with pictures attached as reference:

[0022] Figure 1 Figure 2 shows the binding of Lu-PSMA-617 and Lu-HTK01169 to LNCaP prostate cancer cells by assays performed in triplicate. 18 Representative displacement curves of F-DCFPyL.

[0023] Figure 2 Shows (A) 177 SPECT / CT images of Lu-labeled PSMA-617 and (B) HTK01169 in mice bearing LNCaP tumors. Higher and sustained 177 Lu-HTK01169 uptake.

[0024] Figure 3A Shows 177 Biodistribution of Lu-PSMA-617 in selected organs in mice bearing LNCaP tumor burden (n ≥ 5). The bars are arranged from left to right: 1 hour, 4 hours, 24 hours, 72 hours, and 120 hours.

[0025] Figure 3B Shows 177 Biodistribution of Lu-HTK01169 in selected organs in mice bearing LNCaP tumor burden (n ≥ 5). The bars are arranged from left to right: 1 hour, 4 hours, 24 hours, 72 hours and 120 hours.

[0026] Figure 4 Displayed by 177 Lu-HTK01169 (left column) and 177 Radiation dose (mGy / MBq) delivered by Lu-PSMA-617 (right column) to major organs / tissues of 25 g mice, calculated using OLINDA software.

[0027] Figure 5 show 177 Lu-PSMA-617 (lower) and 177Lu-HTK01169 (top) radiation dose (mGy / MBq) to LNCaP tumor-bearing mice was calculated using OLINDA software. These data were obtained from different tumor masses, but assuming 177 Lu-PSMA-617 and 177 Tumor uptake (%ID, percent injected dose) and residence time of Lu-HTK01169 were identical.

[0028] Figure 6 The results show that the patients injected with saline (control group), 177 Lu-PSMA-617 (18.5 MBq) or 177 Line graph of overall survival of LNCaP tumor-bearing mice (8 mice per group) treated with Lu-HTK 01169 (2.3-18.5 MBq). Shortest to longest median survival: Control group, 2.3 MBq 177 Lu-HTK01169, 18.5MBq 177 Lu-PSMA-617, 4.6MBq 177 Lu-HTK01169, 9.3MBq 177 Lu-HTK01169 and 18.5MBq 177 Lu-HTK01169.

[0029] Figure 7 Shown are line graphs of (A) tumor volume and (B) body weight changes over time after treatment of mice with saline.

[0030] Figure 8 Shows the use 177 Line graphs of (A) tumor volume and (B) body weight changes over time after Lu-PSMA-617 (18.5 MBq) treatment of mice.

[0031] Fig. 9 Shows the use 177 Line graphs of (A) tumor volume and (B) body weight changes over time after Lu-HTK 01169 (18.5 MBq) treatment of mice.

[0032] Fig.10 Shows the use 177 Line graphs of (A) tumor volume and (B) body weight changes over time after Lu-HTK 01169 (9.3 MBq) treatment of mice.

[0033] Fig.11 Shows the use 177 Line graphs of (A) tumor volume and (B) body weight changes over time after Lu-HTK 01169 (4.6 MBq) treatment of mice.

[0034] Fig.12Shows the use 177 Line graphs of (A) tumor volume and (B) body weight changes over time after Lu-HTK 01169 (2.3 MBq) treatment of mice.

[0035] Fig.13 Shows 68 Ga-HTK03026, 68 Ga-HTK03027, 68 Ga-HTK03029 and 68 Maximum intensity projection PET / CT images acquired 1 or 3 hours after Ga-HTK03041 injection in mice bearing LNCaP tumor burden. 68 The Ga-labeled compounds were mainly excreted via the kidneys. 68 Ga-HTK03026, 68 Ga-HTK03027 and 68 Tumor uptake of Ga-HTK03029 was comparable, while 68 Ga-HTK03041 had the highest tumor uptake, which increased from 1 to 3 hours after injection.

[0036] Fig.14 Shows 68 Ga-HTK03055, 68 Ga-HTK03056 and 68 Maximum intensity projection PET / CT images acquired 1 and 3 hours after injection of Ga-HTK03058 in mice bearing LNCaP tumor burden. All three compounds showed some degree of blood retention, as the heart is clearly visible in the image 1 hour after injection. While the uptake in the blood (heart) decreased over time (1 to 3 hours after injection), the uptake in the tumor increased over time.

[0037] Fig.15 Shows 68 Ga-HTK03082, 68 Ga-HTK03085 and 68 Maximum intensity projection PET / CT images acquired 1 and 3 hours after injection of Ga-HTK03086 in mice bearing LNCaP tumor burden. All three compounds are excreted primarily via the renal route. 68 Compared with Ga-HTK03082, 68 Ga-HTK03085 and 68 Ga-HTK03086 showed significantly higher blood retention. 1 to 3 hours after injection, 68 Ga-HTK03085 and 68Tumor uptake of Ga-HTK03086 also increased over time.

[0038] Fig.16 Shows 68 Ga-HTK03087, 68 Ga-HTK03089 and 68 Maximum intensity projection PET / CT images acquired 1 and 3 hours after Ga-HTK03090 injection in mice bearing LNCaP tumor burden. 68 Compared with Ga-HTK03087, 68 Ga-HTK03089 and 68 Ga-HTK03090 showed significantly higher blood retention. 1 to 3 hours after injection, 68 Ga-HTK03089 and 68 Tumor uptake of Ga-HTK03090 also increased over time. DETAILED DESCRIPTION

[0039] As used herein, the terms "comprising," "having," and "including," and their corresponding grammatical variations, are inclusive or open-ended and do not exclude other unrecited elements and / or method steps. When used herein in conjunction with a composition, use, or method, the term "consisting essentially of" means that other elements and / or method steps may be present, but these additions do not substantially affect the functional manner of the recited composition, method, or use. When used herein in conjunction with a composition, use, or method, the term "consisting of" means that no other elements and / or method steps are present.

[0040] Compositions, uses or methods described herein as including certain elements and / or steps may also consist essentially of these elements and / or steps in certain embodiments and include these elements and / or steps in other embodiments, whether or not these embodiments are specifically mentioned. Uses or methods described herein as including certain elements and / or steps may also consist essentially of these elements and / or steps in certain embodiments and include these elements and / or steps in other embodiments, whether or not these embodiments are specifically mentioned.

[0041] Reference to an element with the indefinite article "a" or "an" does not exclude the possibility that there are more than one element, unless the context clearly requires only one element. The singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. In this document, when "a" or "an" is used with "including", it means "one", but it can also mean "one or more", "at least one" and "one or more than one".

[0042] Unless otherwise stated, "certain embodiments," "various embodiments," "one embodiment," and similar terms include particular features described with respect to that embodiment alone or in combination with any other embodiment or embodiments described herein, whether or not other embodiments are referenced directly or indirectly and whether or not the feature or embodiment is described in the context of a method, product, use, composition, compound, etc.

[0043] As used herein, the terms "treat," "therapeutic," and the like include ameliorating symptoms, reducing disease progression, improving prognosis, and reducing cancer recurrence.

[0044] As used herein, the term "diagnostic agent" includes "imaging agent." Thus, "diagnostic radiometal" includes radiometals suitable for use as imaging agents.

[0045] The term "subject" refers to an animal (e.g., a mammal or non-mammal). The subject can be a human or a non-human primate. The subject can be a laboratory mammal (e.g., a mouse, a rat, a rabbit, a hamster, etc.). The subject can be an agricultural animal (e.g., a horse, a sheep, a cow, a pig, a camel, etc.) or a domestic animal (e.g., a dog, a cat, etc.).

[0046] As used herein, the terms "salt" and "solvate" have the usual meaning in chemistry. Therefore, when a compound is a salt or a solvate, it is combined with a suitable counterion. How to prepare salts or exchange counterions is well known in the art. Generally, these salts can be prepared by reacting the free acid form of these compounds with a stoichiometrically suitable base (for example, including but not limited to hydroxides of Na, Ca, Mg or K, carbonates, bicarbonates, etc.), or by reacting the free base form of these compounds with a stoichiometrically suitable acid. This reaction is usually carried out in water or an organic solvent or a mixture of the two. The counterion can be changed by, for example, ion exchange techniques such as ion exchange chromatography. All zwitterions, salts, solvates and counterions are general forms unless a specific form is specifically indicated.

[0047] In certain embodiments, the salt or counterion may be pharmaceutically acceptable for administration to a subject. More generally, with respect to any pharmaceutical composition disclosed herein, non-limiting examples of suitable excipients include any suitable buffer, stabilizer, salt, antioxidant, complexing agent, tonicity agent, cryoprotectant, lyoprotectant, suspending agent, emulsifier, antibacterial agent, preservative, chelating agent, adhesive, surfactant, wetting agent, non-aqueous carrier such as fixed oil or polymer for sustained or controlled release. For example, see Berge et al. 1977. (Journal of Pharmaceutical Sciences 66: 1-19), or Remington-Pharmaceutical Science and Practice, 21st edition (Gennaro et al., ed. Lippincott Williams & Wilkins Philadelphia), each of which is incorporated herein by reference in its entirety.

[0048] In one aspect of the present invention, a compound of Formula Ia or Formula Ib, or a salt or solvate of Formula Ia or Formula Ib is disclosed:

[0049]

[0050] in:

[0051] R 1 yes or -(CH 2 ) 5 CH 3 ;

[0052] R 2 Is I, Br, F, Cl, H, OH, OCH 3 , NH 2 , NO 2 or CH 3 ;

[0053] R 3 yes

[0054] L is -CH 2 NH-, -(CH 2 ) 2 NH-, -(CH 2 ) 3 NH-, or -(CH 2 ) 4 NH-;

[0055] R 4 is a radiometal chelator, optionally combined with a radiometal X; and n is 1-3.

[0056] Wavy Lines The symbols shown across a bond in a chemical formula such as Formula Ia or Formula Ib are intended to define the R group on one side of the wavy line (e.g., R 1 , R 2 and R 3 ) without changing the structural definition on the opposite side of the wavy line. 3 ) bond, the atoms outside the wavy line are included to clarify the R group. Therefore, only the atoms between the two wavy lines constitute the R group.

[0057] In some embodiments, the compound is of Formula Ia or is a salt or solvate of Formula Ia.

[0058] In some embodiments, the compound is of Formula Ib or is a salt or solvate of Formula Ib.

[0059] In some embodiments, R 1 yes In some embodiments, R 1 yes

[0060] In some embodiments, R 1 yes In some embodiments, R 1 for In some embodiments, R 1 For -(CH 2 ) 5 CH 3 .

[0061] R 1 Forming the side chain of an amino acid residue (e.g., 2-naphthylalanine, etc.). In some embodiments, the amino acid is an L-amino acid, i.e. (such as L-2-naphthylalanine, etc.). In some embodiments, the amino acid is a D-amino acid (Such as D-2-naphthylalanine, etc.).

[0062] In some embodiments, R 1 yes In some embodiments, R 1 yes

[0063] In some embodiments, R 1 yes In some embodiments, R 1 yes

[0064] In some embodiments, n = 1. In some embodiments, n = 2. In some embodiments, n = 3.

[0065] As shown in Formulas Ia and Ib, there is only one R on the benzene ring. 2 When not hydrogen, R 2 It may be in the para, meta or ortho position on the benzene ring, that is:

[0066] or or

[0067] In some embodiments, R 2 In some embodiments, R 2 In some embodiments, R 2 In adjacent position.

[0068] In some embodiments, R 2 is H. In some embodiments, R 2 is 1. In some embodiments, R 2 is Br. In some embodiments, R 2 is F. In some embodiments, R 2 is Cl. In some embodiments, R 2 is OH. In some embodiments, R 2 OCH 3 In some embodiments, R 2 Yes NH 2 In some embodiments, R 2 Yes NO 2 In some embodiments, R 2 Yes CH 3 .

[0069] In some embodiments, R 3 yes (i.e. Gly residues).

[0070] In some embodiments, R 3 yes (i.e., an Asp residue). In some embodiments, the Asp residue is D-Asp. In some embodiments, Asp is L-Asp.

[0071] In some embodiments, R 3 yes (i.e., Glu residue). In some embodiments, the Glu residue is D-Glu. In some embodiments, the Glu residue is L-Glu.

[0072] In some embodiments, R 3 yes

[0073] In some embodiments, R 3 yes

[0074] In some embodiments, R 3 yes

[0075] R 4 It can be any radiometal chelator that can bind to the target radiometal (i.e., X) and is functionalized to attach to the amino group. Many suitable radiometal chelators are known, such as those summarized in Price and Orvig, Chem.Soc.Rev., 2014, 43, 260-290, which are all incorporated by reference. In some embodiments, R 4 yes:

[0076] DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) or its derivatives, such as but not limited to DOTAGA;

[0077] TETA (1,4,8,11-tetraazacyclotetradecane-1,4,8,11-tetraacetic acid) or its derivatives, such as but not limited to CB-TE2A (4,11-bis-(carboxymethyl)-1,4,8,11-tetraazabicyclo[6.6.2]-hexadecane);

[0078] SarAR (1-N-(4-aminobenzyl)-3,6,10,13,16,19-hexaazabicyclo[6.6.6]-eicosane-1,8-diamine) or a derivative thereof;

[0079] NOTA (1,4,7-triazacyclononane-1,4,7-triacetic acid) or its derivatives, such as but not limited to NODAGA;

[0080] TRAP (1,4,7-triazacyclononane-1,4,7-trimethyl(2-carboxyethyl)phosphinic acid) or its derivatives;

[0081] HBED (N,N0-bis(2-hydroxybenzyl)-ethylenediamine-N,N0-diacetic acid) or its derivatives;

[0082] 2,3-HOPO (3-hydroxypyridin-2-one) or its derivatives;

[0083] PCTA (3,6,9,15-tetraazabicyclo[9.3.1]-pentadeca-1(15),11,13-triene-3,6,9,-triacetic acid) or its derivatives;

[0084] DFO (deferoxamine) or its derivatives, such as but not limited to tetrahydroxamate DFO* (DFO-star);

[0085] DTPA (diethylenetriaminepentaacetic acid) or its derivatives, such as but not limited to CHX-DTPA (2-(benzyl isothiocyanate)-cyclohexyldiethylenetriaminepentaacetic acid);

[0086] OCTAPA (N,N0-bis(6-carboxy-2-pyridylmethyl)-ethylenediamine-N,N0-diacetic acid) or a derivative thereof (e.g., a picolinic acid derivative); or

[0087] H2-MACROPA (N,N'-bis[(6-carboxy-2-pyridyl)methyl]-4,13-diaza-18-crown-6) or a derivative thereof.

[0088] In some embodiments, X is not present.

[0089] In some embodiments, X is a therapeutic radioactive metal. For example, but not limited to, X can be 64 Cu, 67 Cu, 90 Y. 111 In, 114分钟 , 117m Sn, 153 Sm, 149 Tb, 161 Tb, 177 Lu, 225 Ac, 213 Bi, 224 Ra, 212 Bi, 212 Pb, 225 Ac, 227 Th, 223 Ra, 47 Sc, 186 Re or 188 Re. In some embodiments, X is 64 Cu. In some embodiments, X is 67 Cu. In some embodiments, X is 90 In some embodiments, X is 111 In some embodiments, X is 114 minutes. In some embodiments, X is 117m Sn. In some embodiments, X is 153 Sm. In some embodiments, X is 149 In some embodiments, X is 161 In some embodiments, X is 177 In some embodiments, X is 225 Ac. In some embodiments, X is 213 In some embodiments, X is 224 In some embodiments, X is212 In some embodiments, X is 212 In some embodiments, X is 225 Ac. In some embodiments, X is 227Th In some embodiments, X is 223 In some embodiments, X is 47 Sc. In some embodiments, X is 186 Re. In some embodiments, X is 188 Re.

[0090] In some embodiments, X is a diagnostic radioactive metal. For example, but not limited to, X can be 64 Cu, 111 In, 89 Zr, 44 Sc, 68 Ga, 99m Tc, 86 Y. 152 Tb or 155 In some embodiments, X is 64 Cu. In some embodiments, X is 111 In some embodiments, X is 89 In some embodiments, X is 44 Sc. In some embodiments, X is 68 Ga. In some embodiments, X is 99m In some embodiments, X is 86 In some embodiments, X is 152 In some embodiments, X is 155 Tb.

[0091] In some embodiments, R 1 yes R 3 yes Where R 2 Is I, Br, F, Cl, H, OH, OCH 3 , NH 2 , NO 2 or CH 3 , and there is no X, 90 Y. 67 Ga, 68 Ga, 177 Lu, 225 Ac or 111 In certain embodiments, R 2 In certain embodiments, R 2 is 1. In certain embodiments, X is 177Lu, while in other embodiments, X is 225 Ac.

[0092] In some embodiments, R 1 yes R 3 yes Where R 2 Is I, Br, F, Cl, H, OH, OCH 3 , NH 2 , NO 2 or CH 3 , and there is no X, 90 Y. 67 Ga, 68 Ga, 177 Lu, 225 Ac or 111 In certain embodiments, R 2 In certain embodiments, R 2 In certain embodiments, X is 177 Lu, while in other embodiments, X is 225 Ac. In certain embodiments, n is 3.

[0093] In some embodiments, L is -CH2NH-. In some embodiments, L is -(CH 2 ) 2 NH-. In some embodiments, L is -(CH 2 ) 3 NH-. In some embodiments, L is -(CH 2 ) 4 NH-.

[0094] L forms the side chain of an amino acid residue (e.g., 2,3-diaminopropionic acid (Dap), 2,4-diaminobutyric acid (Dab), ornithine (Orn), or lysine (Lys)). In some embodiments, the amino acid is an L-amino acid, i.e. (eg, L-Dap, L-Dab, L-Orn or L-Lys). In some embodiments, the amino acid is a D-amino acid. (e.g., D-Dap, D-Dab, D-Orn, or D-Lys).

[0095] In some embodiments, the amino acid residue formed by L is an L-amino acid, and the amino acid residue formed by R 1 The amino acid residue formed by L is also an L-amino acid. In some embodiments, the amino acid residue formed by L is a D-amino acid, and the amino acid residue formed by R 1 The amino acid residue formed by L is also a D-amino acid. In some embodiments, the amino acid residue formed by L is an L-amino acid, and the amino acid residue formed by R 1The amino acid residue formed by L is a D-amino acid. In some embodiments, the amino acid residue formed by R 1 The amino acid residues formed are L-amino acids.

[0096] In some embodiments, the compound has Formula II or is a salt or solvate of Formula II:

[0097]

[0098] Where: R 2 is I, Br or methyl; n is 1-3; X is absent, 225 Ac or 177 Lu. In some embodiments, R 2 is 1. In some embodiments, R 2 is Br. In some embodiments, R 2 is methyl. In some embodiments, n=1. In some embodiments, n=2. In some embodiments, n=3. In some embodiments, X is absent. In some embodiments, X is 177 Lu, and is incorporated in the DOTA group. In some embodiments, X is 225 Ac, and is incorporated in the DOTA group.

[0099] In some embodiments, the compound has Formula III or is a salt or solvate of Formula III:

[0100]

[0101] Where X does not exist or is 90 Y. 67 Ga, 68 Ga, 177 Lu, 225 Ac or 111 In. When X in for 177 When Lu, the compound has the following structure, or a salt or solvate thereof:

[0102]

[0103] Example 1 below provides a synthetic scheme for HTK01169 and Lu-HTK01169. Example 2 provides a synthetic scheme for preparing a variety of metal chelated PSMA binding compounds incorporating various choices of the R group of Formulas Ia and Ib.

[0104] The above compounds modulate albumin binding and PSMA binding (as compared to Lu-PSMA-617) to modulate (e.g., enhance) tumor uptake / retention, thereby providing alternative or improved diagnostic or therapeutic agents for PSMA-expressing cancers. In particular, the above compounds contain an albumin binding domain, i.e. (e.g., iodophenylbutyryl in Lu HTK01169; see also PCT Patent Publication No. WO 2008 / 053360), which increases the blood circulation time of the compound. 2 and / or the value of n (i.e. n=1, 2 or 3) and / or the introduction of R 3 Modification of the albumin binding group (e.g., addition of Gly or Asp or Glu containing carboxylates) can adjust (increase or decrease) the albumin binding strength (i.e., binding affinity) of the compound, thereby adjusting the final blood circulation time of the compound. Without wishing to be bound by theory, compounds that bind too strongly to albumin (i.e., have too high an affinity for binding to albumin) will remain in the blood circulation for a long time, and accumulation in tumors will be very low. This will result in reduced total tumor uptake and excessive radiation dose to the bone marrow. At the same time, if the binding affinity to albumin is too weak, the compound will be cleared from the blood circulation too quickly, reducing the chance of accumulation in the tumor. In addition, the above-mentioned compound also contains a Lys-ureido-Glu PSMA binding portion. The PSMA binding strength of the compound can be modified by modifying R 1 Without wishing to be bound by theory, the tunable tumor uptake / retention ability of the above compounds may be due to modulation of albumin binding and / or PSMA binding strength (e.g., compared to Lu-PSMA-617). The diagnostic or therapeutic efficacy may be further modulated by varying the chelator and the bound radiometal. As shown in the following examples, the above variables are adjusted in the above compounds to enhance PSMA-expressing tumor uptake / retention, and thus enhance diagnostic or therapeutic efficacy.

[0105] When X is a diagnostic radiometal, certain embodiments of the compound are disclosed for use in preparing a radiolabeled tracer for imaging PSMA-expressing tissue in a subject. A method of imaging PSMA-expressing tissue in a subject is also disclosed, wherein the method comprises: administering to the subject a composition comprising a certain dosing regimen of the compound and a pharmaceutically acceptable excipient; and imaging the subject's tissue, for example, using positron emission tomography (PET). When the tissue is a diseased tissue (such as a PSMA-expressing cancer), a PSMA-targeted therapy may be selected to treat the subject.

[0106] When X is a therapeutic radiometal, certain embodiments of the compound (or its pharmaceutical composition) are disclosed for use in treating a disease (e.g., cancer) expressing PSMA in a subject. Thus, the use of the compound in the preparation of a medicament for treating a disease expressing PSMA in a subject is provided. Also provided is a method of treating a disease expressing PSMA in a subject, wherein the method comprises: administering to the subject a composition comprising the compound and a pharmaceutically acceptable excipient. For example, but not limited to, the disease may be a cancer expressing PSMA.

[0107] PSMA expression has been detected in a variety of cancers (e.g., Rowe et al., 2015, Annals of Nuclear Medicine 29:877-882; Sathekge et al., 2015, European Journal of Nuclear Medicine and Molecular Imaging 42:1482-1483; Verburg et al., 2015, European Journal of Nuclear Medicine and Molecular Imaging 42:1622-1623; and Pyka et al., Journal of Nucleus Medicine 2015 Nov 19 jnumed.115.164442). Thus, without limitation, a cancer expressing PSMA may be prostate cancer, kidney cancer, breast cancer, thyroid cancer, gastric cancer, colorectal cancer, bladder cancer, pancreatic cancer, lung cancer, liver cancer, brain tumor, melanoma, neuroendocrine tumor, ovarian cancer, or sarcoma. In some embodiments, the cancer is prostate cancer.

[0108] The present invention will be further described in the following examples.

[0109] Embodiment 1: 177 Lu-HTK01169

[0110] 1.1 Materials and methods

[0111] 1.11 General Methods

[0112] All chemicals and solvents were commercially available and used without further purification. Human serum for protein binding analysis was obtained from Innovative Research (Novi, MI). PSMA-617 and HTK01169 were synthesized using a solid phase method on an Aapptec (Louisville, KY) Endeavor 90 peptide synthesizer. Mass analysis was performed using an AB SCIEX (Framingham, MA) 4000QTRAP mass spectrometer system with an ESI source. Non-radioactive and 177Purification and quality control of Lu-labeled peptides were performed on an Agilent (Santa Clara, CA) HPLC system equipped with a 1200 quaternary pump and a 1200 UV absorbance detector. The radio-HPLC system was equipped with a Bioscan (Washington, DC) sodium iodide scintillation detector. The HPLC columns used were Phenomenex (Torrance, CA) semi-preparative columns (Luna C18, 5μ, 250×10 mm) and Phenomenex analytical columns (Luna C18, 5μ, 250×4.6 mm). 177 Lu-labeled peptides were radiolabeled using Capintec (Ramsey, NJ). Dose calibrator for measurement.

[0113] 1.12 Solid Phase Synthesis of PSMA-617 and HTK01169

[0114] Starting from Fmoc-Lys(ivDde)-Wang resin, the synthesis of PSMA-617 and its albumin binder-containing derivative HTK01169 has been improved according to the reported procedure. 16 After coupling the isocyanate of the t-butyl protected glutamyl moiety, 17 The ivDde protecting group was removed with 2% hydrazine in N,N-dimethylformamide (DMF). Subsequent coupling of Fmoc-2-Nal-OH, Fmoc-tranexamic acid and DOTA-tri(t-bu)ester followed by trifluoroacetic acid (TFA) cleavage afforded the crude product of PSMA-617. The crude product was purified by chromatography on a semi-preparative column at 4.5 mL / min (t R After HPLC chromatography with 25% acetonitrile containing 0.1% TFA at a flow rate of 10.5 min (min = 10.5 min), PSMA-617 was obtained in 25% yield. ESI-MS: PSMA-617 C 49 H 72 N 9 O 16 Calculated value [M+H] + 1042.5; Found: [M+H] + 1042.6.

[0115] To synthesize HTK01169, Fmoc-Lys(ivDde)-OH was coupled to the sequence after Fmoc-tranexamic acid. Extension was continued by adding Fmoc-Glu(tBu)-OH and 4-(p-iodophenyl)butyric acid to the N-terminus. Subsequently, the ivDde protecting group was removed with 2% hydrazine in DMF, and DOTA-tri(t-bu)ester was coupled to the Lys side chain. The peptide was cleaved with TFA treatment and a semi-preparative column was used with 37% acetonitrile in water containing 0.1% TFA at a flow rate of 4.5 mL / min (tR =9.7 minutes) and purified by HPLC. The yield of HTK01169 was 21%. ESI-MS: HTK01169C 70 H 100 N 12 O 21 I calculated value [M+H] + 1571.6, measured value [M+H] + 1571.7.

[0116] 1.13 Synthesis of Lu-PSMA-617 and Lu-HTK01169

[0117] A solution of PSMA-617 (5.5 mg, 5.3 μmol) or HTK01169 (4.1 mg, 2.6 μmol) was mixed with LuCl 3 (5 equivalents) were incubated in NaOAc buffer (0.1 M, 500 μL, pH 4.2) at 90°C for 15 minutes and then purified by HPLC using a semi-preparative column. For Lu-PSMA-617, the HPLC conditions were 25% acetonitrile in water, 0.1% TFA, and a flow rate of 4.5 mL / min (tR = 9.7 min). The yield was 62%. ESI-MS: Lu-PSMA-617C 49 H 69 N 9 O 16 Calculated value of [Lu] [M+H] + 1214.4; Found [M+H] + 1214.4. For Lu-HTK01169, the HPLC conditions were 37% acetonitrile in water, 0.1% TFA, and a flow rate of 4.5 mL / min (t R =10.0 min). Yield: 31%. ESI-MS: Lu-HTK01169 C 70 H 97 N 12 O 21 Calculated value of I[Lu][M+H] + 1743.5; Found [M+H] + 1743.9.

[0118] 1.14 In vitro competition binding assay

[0119] As previously described, LNCaP prostate cancer cells and 18 F-DCFPyL was used as a radioligand in an in vitro competition binding assay. 18Briefly, LNCaP cells (400,000 / well) were seeded onto 24-well poly-D-lysine-coated plates for 48 hours. The growth medium was removed and replaced with HEPES-buffered saline (50 mM HEPES, pH 7.5, 0.9% sodium chloride), and the cells were incubated at 37°C for 1 hour. 18 F-DCFPyL (0.1 nM) was added to each well (in triplicate) containing various concentrations (0.5 mM-0.05 nM) of the test compound (Lu-PSMA-617 or Lu-HTK01169). Nonspecific binding was determined in the presence of 10 μM non-radiolabeled DCFPyL. The assay mixture was further incubated for 1 h at 37 °C with gentle agitation. Then, the buffer and hot ligand were removed, and the cells were washed twice with cold HEPES-buffered saline. To harvest the cells, 400 μL of 0.25% trypsin solution was added to each well. Radioactivity was measured on a Wizard2 2480 automated gamma counter from PerkinElmer (Waltham, MA). Nonlinear regression analysis and K were performed using GraphPad Prism 7 software. i calculate.

[0120] 1.15 177 Lu-PSMA-617 and 177 Synthesis of Lu-HTK01169

[0121] Will 177 LuCl 3 (329.3-769.9 MBq, 10-20 μL) was added to a solution of PSMA-617 or HTK01169 (25 μg) in NaOAc buffer (0.5 mL, 0.1 M, pH 4.5). The mixture was incubated at 90°C for 15 minutes and then purified by HPLC. 177 Lu-PSMA-617 and 177 The HPLC purification conditions of Lu-HTK01169 (semi-preparative column, 4.5 mL / min) were 23% and 36% acetonitrile in water (0.1% TFA), respectively. 177 Lu-PSMA-617 and 177 The retention times of Lu-HTK01169 were 15.0 min and 13.8 min, respectively. Quality control was performed on an analytical column at a flow rate of 2 mL / min using the corresponding purification solvent conditions. 177 Lu-PSMA-617 and 177 The retention time of Lu-HTK01169 was about 5.5 minutes.

[0122] 1.16 Plasma protein binding assay

[0123] The plasma protein binding test was performed according to the literature method. 19 Briefly, place 50 μL of PBS in 177 Lu-PSMA-617 or 177 37 kBq of Lu-HTK 01169 was added to 200 μL human serum, and the mixture was incubated at room temperature for 1 minute. The mixture was then loaded onto a membrane filter (Nanosep, 30K, Pall Corporation, USA) and centrifuged for 45 minutes (30, 130 × g). Physiological saline (50 μL) was added and centrifuged for 15 minutes. The top with the membrane filter and the bottom with the solution were counted on a γ counter. The control group used physiological saline instead of human serum.

[0124] 1.17 SPECT / CT imaging, biodistribution and internal radiotherapy studies

[0125] Using NOD-scid IL2Rgamma null SPECT / CT imaging and biodistribution were performed in male (NSG) mice and NOD.Cg-Rag1 tmlMom Iq tm1wjl Internal radiation therapy studies were performed in male SzJ / SzJ (NRG) mice. Mice were housed and experiments were performed according to the guidelines established by the Canadian Council on Animal Care and approved by the Animal Ethics Committee of the University of British Columbia. Mice were anesthetized by inhalation of 2% isoflurane in oxygen and implanted subcutaneously with 1 × 10 7 When tumors reached 5-8 mm in diameter 5-6 weeks after inoculation, mice were used for study.

[0126] SPECT / CT imaging experiments were performed using a MILabs (Utrecht, The Netherlands) U-SPECT-II / CT scanner. Each tumor-bearing mouse was injected with approximately 37 MBq of 177Lu-labeled PSMA-617 or HTK 01169 (2% isoflurane in oxygen). At 4, 24, 72 and 120 hours after injection, mice were allowed to recover and roam freely in the cage and imaged. At each time point, mice were sedated again and placed in the scanner. First, a 5-minute CT scan was performed as an anatomical reference, with the voltage set to 60kV and the current set to 615μA, and then a 60-minute static emission scan of the mouse was collected in list mode using an ultra-high resolution multi-pinhole (1mm pinhole size) collimator. The data was reconstructed using U-SPECT II software with a 20% window width on three energy windows. The center of the photopeak window is located at 208keV, and the centers of the low scattering window and the high scattering window are located at 170 and 255keV, respectively. Images were reconstructed using an ordered subset expectation maximization algorithm (3 iterations, 16 subsets) and a 0.5mm post-processing Gaussian filter. Image attenuation was corrected to injection time in PMOD (PMOD Technologies, Switzerland) before conversion to DICOM for qualitative visualization in Inveon Research Workplace software (Siemens Medical Solutions USA, Inc.).

[0127] For biodistribution studies, mice were injected with 177 Lu-labeled PSMA-617 or HTK01169 (2-4 MBq) were added to the cells at predetermined time points (1, 4, 24, 72, or 120 h after injection) by inhalation of CO 2 Euthanize the mice. Draw blood from the heart immediately and collect the target organs / tissues. Weigh and count the collected organs / tissues using an automated gamma counter. For blocking studies, mice were co-injected 177 Lu-HTK01169 (2-4 MBq) and 50 nmol non-radioactive standard solution were added, and the target organs / tissues were collected 4 h after injection.

[0128] For radiation therapy studies, tumor-bearing mice were injected with saline (control group), 177 Lu-PSMA-617 (18.5 MBq) or 177 Lu-HTK01169 (18.5, 9.3, 4.6 or 2.3 MBq) (n = 8 per group). Tumor size and body weight were measured twice a week from the day of injection (day 0) to the end of the study (day 120). Endpoint criteria were defined as weight loss > 20%, tumor volume > 1000 mm 3 , or tumor activity ulcer.

[0129] 1.18 Radiation dose calculation

[0130] Organ Level Internal Dose Assessment (OLINDA) software v.2.0 was used. 37 Internal dose estimates were calculated. These estimates were calculated using a 25 g MOBY phantom for mice. 38 Use NURBS model for adult male. 39 A previously reported unit density area model was used for tumors. 40 All phantoms and regional models are available in OLINDA and require the input of the total decay number normalized by the injected activity in MBq × h / MBq for each source organ / tumor.

[0131] The biodistribution data (see Tables 1 and 2 below) were used to determine the kinetic input values ​​required by OLINDA. First, each value was decayed to its corresponding time point (values ​​in the table are shown at the time of injection). Then, the different time points of each organ uptake data (%ID / g) were fitted to a single exponential using in-house software developed in Python. and double exponential The best fit was selected based on maximizing the coefficient of determination (R2) of the fit and minimizing the residual. The area under the curve was calculated analytically based on the parameters obtained from the best fit for each organ, which provided the kinetic input values ​​required by OLINDA.

[0132] In the case of the mouse, the adrenal glands, blood, fat, muscle and seminal vesicles were not modeled in the model. These organs were grouped together and included in what OLINDA calls the rest of the body.

[0133] Using Kirschner et al. 41 The proposed method extrapolates the biodistribution data from mice to humans as shown below:

[0134]

[0135] Where m 器官 is the mass of the organ and M represents the total mass of the body. The subscripts indicate whether the values ​​correspond to humans or mice. Organ masses and total weight were taken from the human mass modeled in OLINDA. Since the biodistribution data do not distinguish between the left colon, right colon, and rectum in the OLINDA human model, these three regions of the intestine were assumed to have the same biodistribution of active uptake (%ID / g) as the large intestine. The %ID / g of the blood was assumed to be the %ID / g of the cardiac contents of the model. This value was also used for the calculations based on Wessels et al. 42Bone marrow uptake was calculated using the method described, and we assumed a hematocrit fraction of 0.40 based on patient values ​​shown in this study. Finally, the red bone marrow value used 0.32 times the blood measurement. In the human case, fat, muscle, and seminal vesicles in the biodistribution data were not modeled in the model, so the number of decays in these regions was included in the rest of the body. The data for the mouse case were again fitted, and the values ​​for the total number of decays in MBq×h / MBq were entered into OLINDA.

[0136] Finally, the number of decays in tumors was also calculated based on the biodistribution data from mice and the values ​​were input into the regional model available in OLINDA.

[0137] 1.2 Results

[0138] 1.21 Peptide synthesis and radiochemistry

[0139] PSMA-617 and HTK01169 were synthesized in 25% and 21% yields, respectively. 3 After the reaction, Lu-PSMA-617 and Lu-HTK01169 were obtained with a yield of 62% and 31% respectively by HPLC purification. The identities of PSMA-617, HTK01169 and their LU ligands were confirmed by MS.

[0140] The reaction was carried out in an acetic acid buffer (pH 4.5) at 90°C. 177 Lu labeling, followed by HPLC purification. 177 The radiochemical yield of Lu-PSMA-617 was 86.0±1.7% (n=3), the molar activity was 782±43.3 GBq / μmol, and the radiochemical purity was >99%. 177 The radiochemical yield of Lu-HTK01169 was 63.0±16.2% (n=4), the molar activity was 170±73.6 GBq / μmol, and the radiochemical purity was >99%.

[0141] 1.22 Binding to PSMA and serum proteins

[0142] Lu-PSMA-617 and Lu-HTK01169 inhibited the proliferation of LNCaP cells in a dose-dependent manner. 18 Binding of F-DCFPyL to PSMA ( Figure 1 ), and they calculate K i The values ​​were 0.24±0.06 and 0.04±0.01 nM (n=3), respectively. After incubation with saline and centrifugation, 177 Lu-PSMA-617 and 177The filter-bound radioactivity of Lu-HTK01169 was 5.21±1.42% and 25.8±3.42% (n=3) respectively. 177 Lu-PSMA-617 and 177 The filtered-bound radioactivity of Lu-HTK01169 increased to 82.7±0.32 and 99.2±0.02%, respectively (n=3).

[0143] 1.23 SPECT / CT imaging and biodistribution

[0144] SPECT / CT imaging studies have shown that 177 Lu-PSMA-617 and 177 Lu-HTK01169 is mainly excreted via the renal pathway, especially at early time points (4 and 24 h, Figure 2 ), 177 The renal retention of Lu-HTK01169 was higher. 177 Higher and sustained tumor uptake was observed with Lu-HTK01169. 177 Lu-PSMA-617 and 177 The biodistribution data of Lu-HTK01169 are shown in Figure 3A and 3B (See also Tables 1 and 2.) These data are consistent with the observations from SPECT / CT images.

[0145] Table 1: 177 Biodistribution data of Lu-PSMA-617 in mice bearing LNCaP xenografts.

[0146]

[0147] Table 2: 177 Biodistribution data of Lu-HTK01169 in mice bearing LNCaP xenografts.

[0148]

[0149] 177 Lu-PSMA-617 was rapidly cleared from the blood and non-target organs / tissues. One hour after injection, only 0.68±0.23% ID / g remained in the blood. Uptake was observed in PSMA-expressing tissues, including spleen (3.34±1.77% ID / g), adrenal glands (4.88±2.41% ID / g), kidneys (97.2±19.4% ID / g), lungs (1.34±0.39% ID / g), and LNCaP tumors (15.1±5.58% ID / g). 20-21120 hours after injection, tumor uptake gradually decreased to 7.91±2.82%ID / g. Due to the faster clearance from other tissues / organs, 177 The tumor-to-background contrast of Lu-PSMA-617 increased over time (see Table 1 above).

[0150] With built-in albumin binder, 177 The blood clearance rate of Lu-HTK01169 is relatively lower than 177 Lu-PSMA-617( Figure 3A and 3B ). 177 Tumor uptake of Lu-HTK 01169 continued to increase at early time points, peaked at 24 h post-injection (55.9 ± 12.5% ​​ID / g), and persisted over the course of the study (56.4 ± 13.2% ID / g at 120 h). 177 Similar to Lu-PSMA-617, uptake was also observed in the spleen, adrenal glands, kidneys, and lungs (Table 2 above). 177 Tumor to background contrast of Lu-PSMA-617 also improved over time due to sustained uptake by the tumor and relatively rapid clearance from other organs / tissues. Blocking with cold standards reduced uptake in all collected tissues / organs compared to biodistribution data collected at the same time point (4 h), particularly in PSMA-expressing kidneys (125 ± 16.4% vs. 5.50 ± 1.95% ID / g) and LNCaP tumors (55.9 ± 12.5% ​​vs. 1.70 ± 0.28% ID / g).

[0151] 1.24 Radiation dose calculation

[0152] Based on the biodistribution data obtained from tumor-bearing mice, estimates of the radiation dose delivered to the major organs / tissues of the mice were calculated using OLINDA software. The results are shown in Figure 4 and Table 3, which show the source organ input kinetics (MBq-h / MBq) and target organ doses (mGy / MBq) calculated from the data fit. 177 Compared with Lu-PSMA-617, 177 Lu-HTK01169 delivered 9.4 to 23.1 times higher radiation doses to all major organs except the bladder, which 177 Lu-PSMA-617 received 1.5 times higher radiation dose.

[0153] Table 3: Radiation doses (mGy / GBq) to major organs of a 25 g mouse calculated using OLINDA software.

[0154]

[0155] Similar results were obtained for the calculated radiation dose delivered to human organs / tissues (Table 4). Most human organs / tissues will receive 177 Lu-HTK01169 obtained 11.9 to 24.9 times higher radiation doses. 77 Lu-HTK01169, the brain, heart, red bone marrow, and spleen will receive 6.0-fold, 50.4-fold, 30.4-fold, and 28.1-fold higher doses. The bladder will receive 177 Lu-PSMA-617 has 1.3 times higher radiation dose.

[0156] Table 4: Radiation doses (mGy / GBq) to major human organs (male) calculated using OLINDA software.

[0157]

[0158] according to 177 Lu-PSMA-617 and 177 Lu-HTK01169 LNCaP tumor kinetics, radiation dose delivered to unit density area behavior as shown Figure 5 And as shown in Table 5. 177 Lu-PSMA-617 and 177 The kinetic absorption values ​​of Lu-HTK01169 were 3.80MBq-h / MBq and 31.72MBq-h / MBq, respectively, which were used as input values ​​for OLINDA. 177 The radiation dose of Lu-HTK01169 to LNCaP tumors was 177 8.3 times that of Lu-PSMA-617.

[0159] Table 5: Radiation doses (mGy / MBq) calculated from the unit density area model for LNCaP tumors.

[0160]

[0161] 1.25 Internal Radiation Therapy Research

[0162] The results of the internal radiation therapy studies are shown in Tables 6 and Figure 6 The changes of LNCaP tumor volume and mouse body weight over time after treatment are shown in Figure 7-12 The control group (Group A in Table 6, Figure 7 (A) The tumor volume of mice continued to increase after treatment (saline injection), and the median survival of the control group was only 14 days (when the tumor volume of mice reached 1000mm 3 euthanasia). 177Lu-PSMA-617 (18.5 MBq, Group B in Table 6, Figure 8 Tumors in mice treated with A) initially shrank but later resumed growth, resulting in a median survival of 58 days. 177 Lu-HTK01169 (CF group in Table 6, Fig. 9 The changes in tumor size over time in mice treated with (A)-12(A)) depended on the higher radioactivity injected, resulting in more effective and longer-lasting tumor growth inhibition. 177 The median survival of the mice treated with Lu-HTK01169 was greater than 120, 103, 61, and 28 days, respectively. No weight loss was observed in all mice regardless of treatment ( Figure 7 (B)-12(B)), and all with 18.5MBq 177 Lu-HTK 01169 (Group C in Table 6) treated mice survived until the end of the study (Day 120).

[0163] Table 6: Data from radiotherapy studies, including saline, 177 Lu-PSMA-617 or 177 Median survival after Lu-HTK01169 treatment of tumors.

[0164]

[0165] 1.3 Discussion

[0166] The use of small molecule albumin binders to prolong the circulation time of drugs and maximize their tumor uptake has become an attractive strategy for the design of internal radiotherapy agents. This pioneering work was mainly carried out by scientists at ETH Zurich, who used D-Lys acylated on the ε-amino group with 4-(p-iodophenyl)butyric acid as the albumin binding motif. 22 Previous studies have focused on applying this strategy to the design of folate receptor-targeted radiopharmaceuticals. 23 Because folate receptor α and proton-coupled folate transporter are highly expressed in the renal proximal tubules, radiolabeled folate derivatives generally result in high and sustained renal uptake. 23 Radiolabeled folate derivatives with built-in albumin binders have been reported to significantly prolong blood retention time, increase tumor uptake, and improve the tumor-to-kidney uptake ratio. 23

[0167] Recently, attempts have also been made to use this strategy to design PSMA-targeted internal radiotherapeutic agents with albumin-binding motifs. 24-28 Among the PSMA-targeted drugs that have been reported to bind to albumin,177 Lu-PSMA-ALB-02, 177 Lu-PSMA-ALB-056 and 177 Radiation dose ratio of Lu-RPS-063 to PSMA-expressing tumors 177 Lu-PSMA-617 was 1.8, 2.3 and 3.8 times higher. 26-28 In addition, the effect of PD-1 on PSMA expression was further evaluated in radiation therapy studies in mice bearing PSMA-expressing PC-3PIP tumors. 177 Lu-PSMA-ALB-056. 27 Compared with the control group of mice treated with normal saline, 177 Lu-PSMA-617 or 177 The median survival of mice treated with Lu-PSMA-ALB-056 was prolonged. Most importantly, compared with the treatment with 5MBq 177 Compared with Lu-PSMA-617, only 2MBq 177 Lu-PSMA-ALB-056 was able to produce a slightly better median survival (36 vs. 32 days).

[0168] In this example, a novel albumin binder was used to further improve 177 Tumor uptake of Lu-PSMA-617, the most studied PSMA-targeted internal radiotherapy agent. The most common albumin binding motif reported in the literature consists of D-Lys acylated with the ε-amino group of 4-(p-iodophenyl)butyric acid. 22-23 Since the α-carboxyl group of D-Lys is part of the albumin binding motif, it could not be conjugated to the peptide via solid phase synthesis. 29 As shown in the structure of Lu-HTK01169, a Glu residue was used in place of D-Lys. As a result, the carboxyl group on the Glu side chain was available for binding to albumin, and the α-carboxyl group was conjugated to the peptide via solid phase synthesis. As shown in this example, modification of the linkage between the DOTA chelator and the PSMA-targeting Lys-urea-Glu did not adversely affect efficacy, confirming reports that this linkage modification can be well tolerated. 17 In fact, as shown in this example, a 6-fold improvement in PSMA binding was observed for Lu-HTK01169 compared to Lu-PSMA-617 (K i Value: 0.04±0.01 vs. 0.24±0.06 nM). Without wishing to be bound by theory, the improved PSMA binding may be due to the introduction of the highly lipophilic 4-(p-iodophenyl)butyryl group.

[0169] Evaluation by plasma protein binding assay 177Lu-HTK 01169 has the ability to bind albumin. 177 Compared to Lu-PSMA-617, only <1% of 177Lu-HTK01169 was observed under the same conditions, demonstrating the ability of the albumin binder-modified derivatives to interact with plasma proteins.

[0170] The addition of albumin binders to prolong blood residence time and maximize tumor uptake has been demonstrated by SPECT / CT and biodistribution studies. 177 Lu-HTK 01169 not only showed improved peak tumor uptake ( 177 Lu-HTK 01169: 55.9±12.5%ID / g; 177 Lu-PSMA-617: 15.1 ± 5.58% ID / g), but most importantly, the uptake is sustained, not like 177 Without wishing to be bound by theory, this may be due in part to the enhanced PSMA binding of Lu-HTK01169 compared to Lu-PSMA-617. 177L Improved uptake and longer residence time delivered an 8.3-fold higher radiation dose to LNCaP tumor burden compared to u-PSMA-617. This design strategy may be even more important for radioisotopes with longer half-lives, such as alpha emitters. 225 Ac(t 1 / 2 : 225 Ac, 9.95d; 177 Lu, 6.65d). Currently used in clinical practice 225 Ac is from 229 Th extracted, and supply is limited. 30-31 from 225 Ac-PSMA-617 is converted to 225 Ac-HTK01169 may significantly increase the amount of 225 Number of patients treated with Ac-labeled PSMA-targeting radioligand.

[0171] This example shows that, over time, injection of 37 MBq of 177 Lu-PSMA-617 or 177 Lu-HTK01169, the size of LNCaP tumor burden was rapidly reduced ( Figure 2 The injected radiation dose of ∼37 MBq used to acquire high-resolution SPECT images may exceed that required for treating LNCaP tumors. 177 Lu-HTK01169 dose. Therefore, the internal radiation therapy study in this example compared the use of 18.5 MBq of 177Lu-PSMA-617 or 177 The median survival of mice treated with Lu-HTK01169 was significantly shorter than that of mice treated with only one-half (9.3 MBq), one-quarter (4.6 MBq), or one-eighth (2.3 MBq) of the 177 Median survival of mice treated with Lu-HTK01169. 177 Compared with Lu-HTK 01169 (18.5 MBq, Table 6), 177 One-eighth the dose (2.3 MBq) of Lu-HTK 01169 did not result in similar median survival. However, similar median survival was observed with one-quarter the dose (4.5 MBq) of Lu-HTK 01169. 177 The median survival of mice treated with Lu-HTK01169 was slightly better than that of mice treated with 18.5 MBq 177 Lu-PSMA-617 treated mice (61 days vs. 58 days, Table 6).

[0172] Among the reported albumin-binding PSMA-targeted internal radiotherapy agents, only 177 Lu-PSMA-ALB-056 was evaluated in radiation therapy studies and compared with 177 Lu-PSMA-617 was directly compared. 27 The findings of this example are consistent with those reported by Umbricht et al. 177 There are two major differences in the discovery of Lu-PSMA-ALB-056. 27 For the tumor model, this example used an unmodified endogenous prostate cancer cell line, LNCaP. 177 Lu-PSMA-ALB-056 was evaluated using PC-3PIP, a transduced cell line that expresses PSMA at much higher levels than LNCaP cells. 27 Therefore, in previously reported studies 177 Lu-PSMA-ALB-056 and 177 The Lu-PSMA-617 treatment doses (2 and 5 MBq) were lower than the doses used in this example (2.3-18.5 MBq). The second difference was the size of the tumor. 177 Lu-PSMA-ALB-056~100mm 3 The average tumor size is different. In this embodiment, when the 177 Lu-PSMA-617 or 177 At the start of Lu-HTK01169 treatment, tumor size ranged from 531 to 640 mm 3 The larger tumors in this example may be more resistant to treatment and subsequently require higher radiation doses to achieve similar growth inhibition.

[0173] and 177 Compared with Lu-PSMA-617, albumin binders 177 Lu-HTK01169 provided 3.7 times higher peak uptake and 8.3 times higher total radiation dose to LNCaP tumor burden. Studies on internal radiation therapy in mice bearing LNCaP tumors also showed that 177 Lu-HTK01169, requires only a quarter of the dose 177 Lu-PSMA-617 activity can achieve similar therapeutic effects. When translated into clinical practice, 177 Lu or 225 Ac radiolabeled HTK01169 may also produce similar or improved radiotherapy effects, only 177 Partial drug delivery activity of Lu-PSMA-617. The newly introduced albumin binder in HTK01169 can be constructed directly on the solid phase along the peptide extension. 177 Based on the potential efficacy data obtained for Lu-HTK01169, this new albumin-binding motif may be applied to other (radioactive) peptides to prolong their blood residence time and maximize their therapeutic effect.

[0174] Example 2: Improved Metal Chelated PSMA Binding Compounds

[0175] 2.1 Materials and methods

[0176] 2.11 General Methods

[0177] All chemicals and solvents were commercially available and used without further purification. PSMA targeting peptides were synthesized using a solid phase method on an AAPPTec (Louisville, KY) Endeavor 90 peptide synthesizer. Purification and quality control of cold and radiolabeled peptides were performed on an Agilent HPLC system equipped with a 1200 quaternary pump, a 1200 UV absorbance detector (set at 220 nm), and a Bioscan (Washington, DC) sodium iodide scintillation detector. The operation of the Agilent HPLC system was controlled by Agilent ChemStation software. The HPLC columns used were semi-preparative columns (Luna C18, 5μ, 250×10 mm) and analytical columns (Luna C18, 5μ, 250×4.6 mm) purchased from Phenomenex (Torrance, CA). The collected HPLC eluate containing the desired peptide was lyophilized using a Labconco (Kansas City, MO) FreeZone 4.5 Plus freeze dryer. Mass analysis was performed using an AB SCIEX (Framingham, MA) 4000QTRAP mass spectrometer system with an ESI source. C18 Sep-Pak cartridges (1 cm 3 , 50 mg) was obtained from Waters (Milford Gap, MA). The generator was eluted from iThemba Laboratories (Somerset West, South Africa). 68 Ga and purified using a DGA resin column from Eichrom Technologies LLC (LaSalle, IL). 68 Ga-labeled peptides were radiolabeled using Capintec (Ramsey, NJ) The radioactivity in mouse tissues collected from the biodistribution studies was measured using a dose calibrator, and radioactivity in mouse tissues collected from the biodistribution studies was counted using a Perkin Elmer (Waltham, MA) Wizard2 2480 automated gamma counter.

[0178] 2.12 Synthesis of HTK03026, HTK03027, HTK03029 and HTK03041

[0179] The structures of HTK03026, HTK03027, HTK03029 and HTK03041 are shown below:

[0180]

[0181] The solid phase synthesis of HTK3026, HTK03027, HTK03029 and HTK03041 was modified according to the literature. 16Fmoc-Lys(ivDde)-Wang resin (0.3 mmol, 0.61 mmol / g loading) was suspended in DMF for 30 min. Fmoc was then removed by treating the resin with 20% piperidine in DMF (3 x 8 min). The isocyanate derivative of di-tert-butyl glutamate (3 eq) was prepared according to literature procedure. 17 Prepared and added to the lysine-immobilized resin and reacted for 16 hours. After washing the resin with DMF, the ivDde-protecting group was removed with 2% hydrazine in DMF (5×5 minutes). Fmoc-2-Aoc-OH (for HTK03026), Fmoc-Ala(2-Anth)-OH (for HTK03027), Fmoc-Ala(1-pyridyl)-OH (for HTK03029) or Fmoc-Ala(9-Anth)-OH (for HTK03041) was coupled to the side chain of Lys using Fmoc-protected amino acids (3 eq), HBTU (3 eq), HOBT (3 eq) and N,N-diisopropylethylamine (8 eq). Then, extension was continued by adding Fmoc-tranexamic acid and finally DOTA-tris(t-bu)ester (2-(4,7,10-tris(2-(tert-butoxy)-2-oxoalkyl)-1,4,7,10)-tetraazacyclododec-1-yl)acetic acid).

[0182] The peptide was then deprotected and simultaneously cleaved from the resin by treatment with 95 / 5 trifluoroacetic acid (TFA) / triisopropylsilane (TIS) at room temperature for 2 hours. After filtration, the peptide was precipitated by adding cold ether to the TFA solution. The crude peptide was purified by HPLC using a semi-preparative column. The eluate containing the desired peptide was collected, pooled and lyophilized. For HTK03026, the HPLC conditions were 27% acetonitrile in water, 0.1% TFA, and a flow rate of 4.5 mL / min. The retention time was 10.7 minutes. ESI-MS: HTK03026C 45 H 75 N 9 O 16 Calculated value of [M+H] + 986.5; Found [M+H] + 986.6. For HTK03027, HPLC conditions were 32% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 7.1 min. ESI-MS: HTK03027 C 53 H 74 N 9 O 16 Calculated value of [M+H] + 1092.5; Found [M+H] +1094.6. For HTK03029, HPLC conditions were 33% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 7.3 min. ESI-MS: HTK03029 C 55 H 74 N 9 O 16 Calculated value of [M+H] + 1116.5; Found [M+H] + 1116.6. For HTK03041, HPLC conditions were 31% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 7.2 min. ESI-MS: HTK03041 C 53 H 74 N 9 O 16 Calculated value of d [M+H] + 1092.5 Measured value [M+H] + 1092.6.

[0183] 2.13 Combination of HTK03024, HTK03055, HTK03056, HTK03058, HTK03082, HTK03085, HTK03086, HTK03087, HTK03089 and HTK03090

[0184] The structures of HTK03024, HTK03055, HTK03056, HTK03058, HTK03085, HTK03086, HTK03087, HTK03089 and HTK03090 are shown below:

[0185]

[0186] Where R=I(HTK 03024),CI(HTK 03055),H(HTK03056),Br(HTK03058),F(HTK03085),OCH 3 (HTK03086), NH 2 (HTK03087), NO 2 (HTK03089) or CH 3 (HTK03090).

[0187] The structure of HTK03082 is shown below:

[0188]

[0189] Fmoc-Lys(ivDde)-Wang resin (0.3 mmol, 0.61 mmol / g loading) was suspended in DMF for 30 min. Fmoc was then removed by treating the resin with 20% piperidine in DMF (3 x 8 min). The isocyanate derivative of di-tert-butyl glutamate (3 eq) was prepared according to literature procedure. 17 Prepared and added to the lysine-immobilized resin and reacted for 16 hours. After washing the resin with DMF, the ivDde-protecting group was removed with 2% hydrazine in DMF (5×5 minutes). Fmoc-2-Nal-OH was then coupled to the side chain of Lys by solid phase peptide synthesis using Fmoc-based chemistry, followed by coupling to Fmoc-tranexamic acid, Fmoc-Lys(ivDde)-OH, and Fmoc-Gly-OH. All couplings were performed in DMF using Fmoc-protected amino acids (3 eq), HBTU (3 eq), HOBT (3 eq), and DIEA (8 eq). Then, extension was continued by adding 4-(p-iodophenyl)butyric acid (for HTK03024), 4-(p-chlorophenyl)butyric acid (for HTK03055), 4-phenylbutyric acid (for HTK03056), 4-(p-bromophenyl)butyric acid (for HTK03058), 3-phenylpropionic acid (for HTK03082), 4-(p-fluorophenyl)butyric acid (for HTK03085), 4-(p-methoxyphenyl)butyric acid (for HTK03086), 4-(p-(tert-butoxycarbonyl)aminophenyl)butyric acid (for HTK03087), 4-(p-nitrophenyl)butyric acid (for HTK03089) or 4-(p-tolyl)butyric acid (for HTK03090) to the same peptide coupled to the resin using Fmoc-based chemistry. After selective removal of the ivDde protecting group with 2% hydrazine in DMF (5 x 5 min), the chelating agent DOTA was then coupled to the side chain of Lys to afford the precursor.

[0190] The peptide was then deprotected and simultaneously cleaved from the resin by treatment with 95 / 5 trifluoroacetic acid (TFA) / triisopropylsilane (TIS) for 2 hours at room temperature. After filtration, the peptide was precipitated by adding cold ether to the TFA solution. The crude peptide was purified by HPLC using a semi-preparative column. The eluate containing the desired peptide was collected, pooled and lyophilized. For HTK03024, the HPLC conditions were 37% acetonitrile in water, 0.1% TFA, and a flow rate of 4.5 mL / min. The retention time was 8.8 minutes. ESI-MS: HTK03024C 67 H 96 N 12 O 19 Calculated value of I [M+H] + 1499.6; Found [M+H] +1499.6. For HTK03055, HPLC conditions were 35% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 9.7 min. ESI-MS: HTK03055C 67 H 96 N 12 O 19 Calculated value of Cl[M+H] + 1407.7; Found [M+H] + 1407.7. For HTK03056, HPLC conditions were 0-80% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min, 20 min. Retention time was 13.4 min. ESI-MS: HTK03056 C 67 H 97 N 12 O 19 Calculated value of [M+H] + 1373.7; Found [M+H] + 1373.8. For HTK03058, HPLC conditions were 0-80% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min, 20 min. Retention time was 13.4 min. ESI-MS: For HTK03058 C 67 H 96 N 12 O 19 Calculated value of Br[M+H] + 1451.6; Found [M+H] + 1451.6. For HTK03082, HPLC conditions were 31% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 11.1 min. ESI-MS: HTK03082 C 66 H 95 N 12 O 19 Calculated value 1359.7; Found [M+H] + 1359.9. For HTK03085, HPLC conditions were 34% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 9.0 min. ESI-MS: HTK03085 C 67 H 96 N 12 O 19 Calculated value of F [M+H] + 1391.7; Found [M+H] +1391.9. For HTK03086, HPLC conditions were 33% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 9.1 min. ESI-MS: HTK03090 C 68 H 99 N 12 O 20 Calculated value of [M+H] + 1403.7; Found [M+H] + 1404.1. For HTK03087, HPLC conditions were 23% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 13.9 min. ESI-MS: HTK03087 C 67 H 98 N 13 O 19 The calculated value of + 1388.7; found [M+H] 1389.0. For HTK03089, HPLC conditions were 33% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 10.6 min. ESI-MS: HTK03089C 67 H 96 N 13 O 21 Calculated value of [M+H] + 1418.7; Found [M+H] + 1419.0. For HTK03090, HPLC conditions were 35% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 9.1 min. ESI-MS: HTK03090C 68 H 99 N 12 O 19 Calculated value of [M+H] + 1387.7; Found [M+H] + 1387.9.

[0191] 2.14 Synthesis of Ga-labeled standards

[0192] To prepare Ga-labeled standards, a solution of each precursor was mixed with GaCl 3(5 eq.) was incubated in NaOAc buffer (0.1 M, 500 μL, pH 4.2) at 80°C for 15 minutes. The reaction mixture was then purified by HPLC using a semi-preparative column, and the HPLC eluate containing the desired peptide was collected, combined, and lyophilized. For Ga-HTK03026, the HPLC conditions were 27% acetonitrile in water, 0.1% TFA, and a flow rate of 4.5 mL / min. The retention time was 9.4 minutes. ESI-MS: Ga-HTK03026 C 44 H 73 N 9 O 16 Calculated value of Ga[M+H] + 1052.4; Found [M+H] + 1052.5. For Ga-HTK03027, HPLC conditions were 32% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 9.5 min. ESI-MS: Ga-HTK03027 C 53 H 72 N 9 O 16 Calculated value of Ga[M+H] + 1159.4; Found [M+H] + 1161.4. For HTK03029, HPLC conditions were 33% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 10.3 min. ESI-MS: Ga-HTK03029 C 55 H 72 N 9 O 16 Calculated value of Ga[M+H] + 1183.4; Found [M+H] + 1183.4. For Ga-HTK03041, HPLC conditions were 31% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 9.3 min. ESI-MS: Ga-HTK03041 C 53 H 72 N 9 O 16 Calculated value of Ga[M+H] + 1159.4; Found [M+H] + 1159.4. For Ga-HTK03024, HPLC conditions were 39% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 8.0 min. ESI-MS: Ga-HTK03024C 67 H 93 N 12 O 19Calculated value of IGa[M+H] + 1565.5; Found [M+H] + 1565.5. For Ga-HTK03055, HPLC conditions were 35% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 12.7 min. ESI-MS: Ga-HTK03055 C 67 H 94 N 12 O 19 Calculated value of ClGa[M+H] + 1474.6; Found [M+H] 2+ 738.4. For Ga-HTK03056, HPLC conditions were 34% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 9.0 min. ESI-MS: Ga-HTK03056 C 67 H 94 N 12 O 19 Calculated value of Ga[M+H] + 1439.6; Found [M+H] + 1439.8. For Ga-HTK03058, HPLC conditions were 34% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 10.3 min. ESI-MS: Ga-HTK03058 C 67 H 93 N 12 O 19 Calculated value of BrGa[M+H] + 1517.5; Found [M+H] + 1518.0. For Ga-HTK03082, HPLC conditions were 31% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 12.5 min. ESI-MS: Ga-HTK03082C 66 H 93 N 12 O 19 Calculated value of Ga[M+H] + 1426.6; Found [M+H] + 1426.9. For Ga-HTK03085, HPLC conditions were 34% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 9.0 min. ESI-MS: Ga-HTK03085 C 67 H 94 N 12 O 19 Calculated value of FGa [M+H]+ 1458.6; Found [M+H] + 1459.6. For Ga-HTK03086, HPLC conditions were 33% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 10.7 min. ESI-MS: Ga-HTK03086 C 68 H 96 N 12 O 20 Calculated value of Ga: 1469.6; Found [M+H] + 1469.8. For Ga-HTK03087, HPLC conditions were 23% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 14.7 min. ESI-MS: Ga-HTK03087 C 67 H 96 N 13 O 19 Calculated value of Ga[M+H] + 1455.6; Found [M+H] + 1455.8. For Ga-HTK03089, HPLC conditions were 33% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 12.0 min. ESI-MS: Ga-HTK03089 C 67 H 94 N 13 O 21 Calculated value of Ga[M+H] + 1485.6; Found [M+H] + 1485.9. For Ga-HTK03090, HPLC conditions were 35% acetonitrile in water, 0.1% TFA, flow rate 4.5 mL / min. Retention time 11.3 min. ESI-MS: Ga-HTK03090 C 68 H 97 N 12 O 19 Calculated value of Ga[M+H] + 1454.6; Found [M+H] + 1455.8.

[0193] 2.15 Cell culture

[0194] The LNCaP cell line (LNCap clone FGC, CRL-1740) was obtained from ATCC. It was established from a metastatic site of the left supraclavicular lymph node of human prostate cancer. The cells were cultured in PRMI 1640 medium supplemented with 10% FBS, penicillin (100 U / mL), and streptomycin (100 μg / mL) at 37°C in a humidified incubator containing 5% CO. 2 Cells grown to 80-90% confluence were then washed with sterile phosphate buffered saline (1×PBS pH 7.4) and trypsinized. The number of harvested cells was counted using a Hausser Scientific (Horsham, PA) hemacytometer.

[0195] 2.16 68 Synthesis of Ga-labeled compounds

[0196] The purified 68 Ga was added to a 4 mL glass vial pre-filled with 0.7 mL HEPES buffer (2 M, pH 5.0) and 50 μg of DOTA precursor. The radiolabeling reaction was carried out under microwave heating for 1 minute. The reaction mixture was purified by HPLC using the same semi-preparative column and conditions provided in Section 2.14 to purify its respective non-radioactive Ga-labeled standard solution.

[0197] 2.17 PET / CT Imaging and Biodistribution

[0198] Imaging and biodistribution experiments were performed using NODSCID 1L2RγKO male mice. Mice were anesthetized by inhalation of 2% isoflurane in oxygen and implanted subcutaneously with 1 × 10 7 When tumors grew to 5-8 mm in diameter within 5-6 weeks, mice were imaged or used for biodistribution studies.

[0199] PET imaging experiments were performed using a Siemens Inveon microPET / CT scanner. Each tumor-bearing mouse was injected with 6-8MBq of 68Ga-labeled tracer (2% isoflurane in oxygen) through the tail vein under anesthesia. The mice were allowed to regain consciousness and move freely in the cage. After 50 minutes, the mice were again sedated by inhaling 2% isoflurane in oxygen and placed in the scanner. A 10-minute CT scan was first performed, and localization and attenuation correction were performed after segmentation to reconstruct the PET image. Then, 10 minutes of static PET imaging was performed to determine the uptake in the tumor and other organs. During the acquisition process, the mice were kept warm with a heating pad. For imaging studies obtained 3 hours after injection (intraperitoneal injection), the mice were placed in a micro PET / CT scanner 170 minutes after intraperitoneal injection. Then, CT acquisition was performed as described above, and 15 minutes of static PET imaging was performed to determine the uptake in the tumor and other organs.

[0200] For biodistribution studies, mice were injected with radiotracer as described above. At predetermined time points (1 or 3 h), mice were anesthetized by inhalation of 2% isoflurane and monitored by inhalation of CO 2 Euthanasia was performed. Blood was immediately drawn from the heart and the target organs / tissues were collected. The collected organs / tissues were weighed and counted using an automated gamma counter. The uptake of each organ / tissue was normalized to the injected dose using a standard curve and expressed as a percentage of the injected dose per gram of tissue (%ID / g).

[0201] 2.2 Results

[0202] The results of this example are shown in Tables 7-10 and Figure 13-16 Combined with the results of Example 1, these results indicate that various compounds contained in Formula 1-a and Formula 1-b are particularly useful.

[0203] Table 7: 68 Biodistribution data and tumor-to-background contrast of Ga-labeled HTK03026, HTK03027, HTK03029, and HTK03041 in mice bearing PSMA-expressing LNCaP tumors.

[0204]

[0205]

[0206] Table 8: 68 Biodistribution data and tumor-to-background contrast of Ga-labeled HTK03089 and HTK03090 in mice bearing PSMA-expressing LNCAP tumors.

[0207]

[0208]

[0209] U.S. Provisional Application No. 62 / 575,460, filed on October 22, 2017, is incorporated herein by reference in its entirety. To the extent there may be a conflict between definitions provided in this application and definitions provided in documents incorporated by reference, definitions in this application shall prevail over definitions in documents incorporated by reference.

[0210] This application describes one or more embodiments. However, it will be apparent to those skilled in the art that many variations and modifications may be made without departing from the scope of the invention as defined in the claims.

[0211]

[0212]

[0213] References

[0214] 1. Carter, RE; Feldman, AR; Coyle, JT Prostate-specific membrane antigen is a hydrolase with substrate and pharmacologic characteristics of aneuropeptidase. Proc. Natl. Acad. Sci. USA 1996, 93, 749-753.

[0215] 2. Silver, DA; Pellicer, I.; Fair, WR; Heston, WD; Cordon-Cardo, C. Prostate-specific membrane antigen expression in normal and malignant humantissues. Clin. Cancer Res. 1997, 3, 81-85.

[0216] 3.Sokoloff,R.L.;Norton,K.C.;Gasior,C.L.;Marker,K.M.;Grauer,L.S.Adual-monoclonal sandwich assay for prostate-specific membrane antigen:levelsin tissues,seminal fluid and urine.Prostate 2000.43.150-157.

[0217] 4.Bander,N.H.;Milowsky,M.I.;Nanus,D.M.;Kostakoglu,L.;Vallabhajosula,S.;Goldsmith,S.J.Phase I trial of 177 lutetium-labeled J591,a monoclonalantibody to prostate-specific membrane antigen,in patients with androgen-independent prostate cancer.J.Clin.Oncol.2005,23,4591-4601.

[0218] 5.Afshar-Oromieh,A.;Haberkorn,U.;Zechmann,C.;Armor,T.;Mier,W.;Spohn,F.;Debus,N.;Holland-Letz,T.;Babich,J.;Kratochwil,C.Repeated PSMA-targetingradioligand therapy of metastatic prostate cancer with 131 I-MIP-1095.Eur.J.Nucl.Med.Mol.Imaging 2017,44,950-959.

[0219] 6.Heck,M.M.;Retz,M.;D’Alessandria,C.;Rauscher,I.;Scheidhauer,K.;Maurer,T.;Storz,E.;Janssen,F.;Schottelius,M.;Wester,H.J.;Gschwend,J.E.;Schwaiger,M.;Tauber,R.;Eiber,M.Systemic radioligand therapy with 177 Lu labeledprostate specific membrane antigen ligand for imaging and therapy in patientswith metastatic castration resistant prostate cancer.J.Urol.2016,196.382-391.

[0220] 7.Kratochwil,C.;Giesel,F.L.;Stefanova,M.;Benesova,M.;Bromzel,M.;Afshar-Oromieh,A.;Mier,W.;Eder,M.;Kopka,K.;Haberkorn,U.PSMA-targetedradionuclide therapy of metastatic castration-resistant prostate cancer with 177 Lu-labeled PSMA-617.J.Nucl.Med.2016,57,1170-1176.

[0221] 8.Rahbar,K.;Bode,A.;Weckesser,M.;Avramovic,N.;Claesener,M.;Stegger,L.;Bogemann,M.Radioligand thcrapy with 177 Lu-PSMA-617 as a novel therapeuticoption in patients with metastatic castration resistant prostate cancer.Clin.Nucl.Med.2016.41.522-528.

[0222] 9.Fendler,W.P.;Reinhardt,S.;Ilhan,H.;Delker,A.;Boning,G.;Gildehaus,F.J.;Stief,C.;Bartenstein,P.;Gratzke,C.;Lehner,S.;Rominger,A.Preliminaryexperience with dosimetry,response and patient reported outcome after 177 Lu-PSMA-617 therapyfor metastatic castration-resistant prostatecancer.Oncotarget 2017,8,3581-3590.

[0223] 10.Rahbar,K.;Ahmadzadehfar,H.;Kratochwil,C.;Haberkorn,U.;Schafers,M.;Essler,M.;Baum,R.P.;Kulkarni,H.R.;Schmidt,M.;Drzezga,A.;Bartenstein,P.;Pfestroff,A.;Luster,M.;Lutzen,U.;Marx,M.;Prasad,V.;Brenner,W.;Heinzel,A.;Mottaghy,F.M.;Ruf,J.;Meyer,P.T.;Heuschkel,M.;Eveslage,M.;Bogemann,M.;Fendler,W.P.;Krause,B.J.German multicenter study investigating 177 Lu-PSMA-617radioligand therapy in advanced prostate cancer patients.J.Nucl.Med.2017,58,85-90.

[0224] 11.Ahmadzadehfar,H.;Wegen,S.;Yordanova,A.;Fimmers,R.;Kurpig,S.;Eppard,E.;Wei,X.;Schlenkhoff,C.;Hauser,S.;Essler,M.Overall survival andresponse pattern of castration-resistant metastatic prostate cancer tomultiple cycles of radioligand therapy using[ 177 Lu]Lu-PSMA-617.Eur.J.Nucl.Med.Mol.Imaging 2017,44,1448-1454.

[0225] 12.Brauer,A.;Grubert,L.S.;Roll,W.;Schrader,A.J.;Schafers,M.;Bogemann,M.;Rahbar,K. 177 Lu-PSMA-617 radioligand therapy and outcome in patients withmetastasized castration-resistant prostate cancer.Eur.J.Nucl.Med.Mol.Imaging2017,44,1663-1670.

[0226] 13.Yadav,M.P.;Ballal,S.;Tripathi,M.;Damle,N.A.;Sahoo,R.K.;Seth,A.;Bal,C. 177 Lu-DKFZ-PSMA-617 therapy in metastatic castration resistant prostatecancer:safety,efficacy,and quality of life assessment.Eur.J.Nucl.Med.Mol.Imaging 2017,44,81-91.

[0227] 14.Hofman,M.S.;Violet,J.;Hicks,R.J.;Ferdinandus,J.;Thang,S.P.;Akhurst,T.;Iravani,A.;Kong,G.;Kumar,A.R.;Murphy,D.G.;Eu,P.;Jackson,P.;Scalzo,M.;Williams,S.G.;Sandhu,S.[ 177 Lu]-PSMA-617 radionuclide treatment in patientswith metastatic castration-resistant prostate cancer(LuPSMA trial):a single-centte,single-arm,phase 2 study.Lancet Oncol.2018,19,825-833.

[0228] 15.Kratochwil,C.;Bruchertseifer,F.;Giesel,F.L.;Weis,M.;Verburg,F.A.;Mottaghy,F.;Kopka,K.;Apostolidis,C.;Haberkorn,U.;Morgenstern,A. 225 Ac-PSMA-617for PSMA-targeted α-radiation therapy of metastatic castration-resistantprostate cancer.J.Nucl.Med.2016,57,1941-1944.

[0229] 16.Benesova,M.;Schafer,M.;Bauder-Wust,U.;Afshar-Oromieh,A.;Kratochwil,C.;Mier,W.;Haberkorn,U.;Kopka,K.;Eder,M.Preclinical evaluation ofa tailor-made DOTA-conjugated PSMA inhibitor with optimized linker moiety forimaging and endoradiotherapy of prostate cancer.J.Nucl.Med.2015,56,914-920.

[0230] 17.Benesova,M.;Bauder-Wust,U.;Schafer,M.;Klika,K.D.;Mier,W.;Haberkorn,U.;Kopka,K.;Eder,M.Linker modification strategies to control theprostate-specific membrane antigen(PSMA)-targeting and pharmacokineticproperties of DOTA-conjugated PSMA inhibitors.J.Med.Chem.2016,59,1761-1775.

[0231] 18.Kuo,H.T.;Pan,J.;Zhang,Z.;Lau,J.;Merkens,H.;Zhang,C.;Colpo,N.;Lin,K.S.;Benard,F.Effects of linker modification on tumor-to-kidney contrast of 68 Ga-labeled PSMA-targeted imaging probes.Mol.Pharmaceutics 2018,doi:10.1021 / acs.molpharmaceut.8b00499

[0232] 19.Meckel,M.;Kubicek,V.;Hermann,P.;Miederer,M.;Rosch,F.A DOTA basedbisphosphonate with an albumin binding moiety for delayed body clearance forbone targeting.Nucl.Med.Biol.2016,43,670-678.

[0233] 20.Harada,N.;Kimura,H.;Onoe,S.;Watanabe,H.;Matsuoka,D.;Arimitsu,K.;Ono,M,;Saji,H.Synthesis and biological evaluation of novel 18F-labeled probestargeting prostate-specific membrane antigen for positron emission tomographyof prostate cancer.J.Nucl.Med.2016,57,1978-1984.

[0234] 21.Chatalic,K.L.S.;Heskamp,S.;Konijnenberg,M.;Molkenboer-Kuenen,J.D.M.;Franssen,G.M.;Clahsen-van Groningen,M.C.;Schottelius,M.;Wester,H.J.;van Weerden,W.M.;Boerman,O.C.;de Jong,M.Towards personalized treatment ofprostate cancer:PSMA I&T,a promising prostate-specific membrane antigen-targeted theranostic agent.Theranostics 2016,6,849-861.

[0235] 22.Dumelin,C.E.;Trussel,S.;Buller,F.;Trachsel,E.;Bootz,F.;Zhang,Y.;Mannocci,L.;Beck,S.C.;Drumea-Mirancea,M.;Seeliger,M.W.;Baltes,C.;Muggler,T.;Kranz,F.;Rudin,M.;Melkko,S.;Scheuermann,J.;Neri,D.A portable albumin binderfrom a DNA-encoded chemical library.Angew.Chem.Int.Ed.2008,47,3196-3201.

[0236] 23.Muller,C.;Struthers,H.;Winiger,C.;zhernosekov,K.;Schibli,R.DOTAconjugate with an albumin-binding entity enables the first folic acid-targeted177 Lu-radionuclide rumor therapy in mice.J.Nucl.Med.2013,54,124-131.

[0237] 24.Choy,C.J.;Ling,X.;Geruntho,J.J.;Beyer,S.K.;Latoche,J.D.;Langton-Webster,B.;Anderson,C.J.;Berkman,C.E. 177 Lu-Labeled phosphoramidate-based PSMAinhibitors:The effect of an albumin binder on biodistribution and therapeuticefficacy in prostate tumor-bearing mice.Theranostics 2017.7.1928-1939.

[0238] 25.Kelly,J.M.;Amor-Coarasa,A.;Nikolopoulou,A.;Wustemann,T.;Barelli,P.;Kim,D.;Williams,C.;Zheng,X.;Bi,C.;Hu,B.;Warren,J.D.;Hage,D.S.;DiMagno,S.G.;Babich,J.W.Dual-target binding ligands with modulated pharmacokineticsfor endoradiotherapy of prostate cancer.J.Nucl.Med.2017,58,1442-1449.

[0239] 26.Benesova,M.;Umbricht,C.A.;Schibli,R.;Müller,C.Albumin-binding PSMAligands:optimization ofthe tissue distribution profile.Mol.Pharmaceutics2018,15,934-946.

[0240] 27.Umbricht,C.A.;Benesova,M.;Schibli,R.;Müller,C.Preclinicaldevelopment of novel PSMA-targeting radioligands:Modulation of albumin-binding properties to improve prostate cancer therapy.Mol.Pharmaceutics 2018,15,2297-2306.

[0241] 28.Kelly,J.;Amor-Coarasa,A.;Ponnala,S.;Nikolopoulou,A.;Williams,C.;Schlyer,D.;Zhao,Y.;Kim,D.;Babich,J.W.Trifunctional PSMA-targeting constructsfor prostate cancer with unprecedented localization to LNCaP tumors.Eur.J.Nucl.Med.Mol.Imaging 2018,doi:10.1007 / s00259-018-4004-5.

[0242] 29.Liu,z.;Chen,x.Simple Bioconjugate chemistry serves great clinicaladvances:albumin as a versatile platform for diagnosis and precisiontherapy.Chem.Soc.Rev.2016,45,1432-1456.

[0243] 30.Apostolidis,C.;Molinet,R.;Rasmussen,G.;Morgenstern,A.Production ofAc-225 from Th-229 for targeted α therapy.Anal.Chem.2005,77,6288-6291.

[0244] 31.Walsh,K.M.Brookhaven National Laboratory:Radioisotopes for medicalimaging and disease treatment.J.Nucl.Med.2017.58,11N-12N.

[0245] 37.Stabin MG,Sparks RB,Crowe E.OLINDA / EXM:the second-generationpersonal computer software for internal dose assessment in nuclear medicine.JNucl Med.2005;46:1023-1027.

[0246] 38.Keenan MA,Stabin MG,Segars WP,Fernald MJ.RADAR realistic animalmodel series for dose assessment.J Nucl Med.2010;51:471-476.

[0247] 39.Stabin MG,Xu XG,Emmons MA,Segars WP,Shi C,Fernald MJ.RADARreference adult,pediatric,and pregnant female phantom series for internal andexternal dosimetry.J Nucl Med.2012;53:1807-1813.

[0248] 40.Stabin MG,Konijnenberg MW.Re-evaluation of absorbed fractions forphotohs and electrons in spheres of various sizes.J Nucl Med.2000;41:149-160.

[0249] 41.Kirschner AS,Ice RD,Beierwaltes WH.Radiation dosimetry of 131I-19-iodocholesterol:the pitfalls of using tissue concentration data.The author’sreply.J Nucl Med.1975;16:248-249.

[0250] 42.Wessels BW,Bolch WE,Bouchet LG,et al.Bone marrow dosimetry usingblood-based models for radiolabeled antibody therapy:a multiinstitutionalcomparison.J Nucl Med.2004;45(10):1725-1733.

Claims

1. A compound having the following structure: in, X does not exist.

2. A compound having the following structure: in, X is 90 Y, 67 Ga, 68 Ga, 177 Lu, 225 Ac, or 111 In.

3. The compound according to claim 2, wherein X is 177 Lu.

4. A compound having the following structure: in, R is 5. A compound according to claim 4, wherein R is 6. A compound having the following structure: in, R is And wherein the compound is bound to a radioactive metal.

7. A compound according to claim 6, wherein R is 8. The compound according to claim 6 or 7, wherein the radioactive metal is 64 Cu, 111 ln, 89 Zr, 44 Sc, 68 Ga, 99m Tc, 86 Y, 152 Tb or 155 Tb.

9. The compound according to claim 6 or 7, wherein the radioactive metal is 68 Ga.

10. Use of a composition comprising a compound according to any one of claims 2 and 6 to 9 and a pharmaceutically acceptable excipient for the preparation of a medicament for imaging cancer expressing prostate specific membrane antigen (PSMA).

11. Use of a composition comprising the compound of claim 3 and a pharmaceutically acceptable excipient in the preparation of a medicament for treating prostate cancer.

Images