Patent Publication Number: US-2020281934-A1

Title: Sstr-targeted conjugates and formulations thereof

Description:
REFERENCED TO RELATED APPLICATIONS 
     The present application claims priority to U.S. Provisional Patent Application No. 62/577,897, filed Oct. 27, 2017, entitled “SSTR-TARGETED CONJUGATES AND FORMULATIONS THEREOF”, and U.S. Provisional Patent Application No. 62/679,230, filed Jun. 1, 2018, entitled, “SSTR-TARGETED CONJUGATES AND FORMULATIONS THEREOF”, the contents of each of which are herein incorporated by reference in their entirety. 
    
    
     FIELD OF THE DISCLOSURE 
     The invention generally relates to the field of using conjugates targeting somatostatin receptors for treating cancer. 
     BACKGROUND 
     Developments in nanomedicine are generally directed towards improving the pharmaceutical properties of the drugs and, in some cases, enhancing the targeted delivery in a more cell-specific manner. Several cell-specific drugs have been described, and include monoclonal antibodies, aptamers, peptides, and small molecules. Despite some of the potential advantages of such drugs, a number of problems have limited their clinical application, including size, stability, manufacturing cost, immunogenicity, poor pharmacokinetics and other factors. There is a need in the art for improved drug targeting and delivery and to design drugs with deeper solid tumor penetration. 
     SUMMARY OF THE DISCLOSURE 
     The present application dicloses conjugates of a somatostatin receptor binding moiety and an active agent, e.g., a cancer therapeutic agent. The conjugates are useful for delivering active agents such as tumor cytotoxic agents to cells expressing somatostatin receptors. Pharmaceutical compositions comprising the conjugates and methods of using the conjugates are also provided. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows plasma pharmacokinetics of Conjugate 57 at 18 mg and key metabolites: DM1, the ligand (SSTR2 binding peptide), and free sulfhydryl DM1. Data were collected from 5 patients. 
         FIG. 2  shows decrease in circulating biomarkers of neuroendocrine disease: chromogranin A ( FIG. 2A ), neuron specific enolase ( FIG. 2B ) and circulating tumor cells ( FIG. 2C ), in a patient with GI NET treated with Conjugate 57. 
     
    
    
     DETAILED DESCRIPTION 
     At least five somatostatin receptors subtypes have been characterized, and tumors can express various receptor subtypes. (e.g., see Shaer et al., Int. 3. Cancer 70:530-537, 1997). Naturally occurring somatostatin and its analogs exhibit differential binding to receptor subtypes. Applicants have exploited this feature to create novel conjugates comprising a targeting moiety that binds to a SSTR, wherein the targeting moiety is attached to an active agent. 
     The toxicity of a conjugate containing a SSTR-binding targeting moiety linked to an active agent for cells that do not express SSTRs is predicted to be decreased compared to the toxicity of the active agent alone. Further, the ability of the conjugated active agent to enter a cell is decreased compared the ability to enter a cell of the active agent alone. Accordingly, the conjugates comprising an active agent as described herein generally have decreased toxicity for non-SSTR expressing cells and at least the same or increased toxicity for SSTR expressing cells compared to the active agent alone. 
     I. Conjugates 
     Conjugates include an active agent or prodrug thereof attached to a targeting moiety, e.g., a molecule that can bind to an SSTR, by a linker. The conjugates can be a conjugate between a single active agent and a single targeting moiety, e.g., a conjugate having the structure X-Y-Z where X is the targeting moiety, Y is the linker, and Z is the active agent. 
     In some embodiments the conjugate contains more than one targeting moiety, more than one linker, more than one active agent, or any combination thereof. The conjugate can have any number of targeting moieties, linkers, and active agents. The conjugate can have the structure X-Y-Z-Y-X, (X-Y) n -Z, X-(Y-Z) n , X-Y-Z n , (X-Y-Z) n , (X-Y-Z-Y) n -Z where X is a targeting moiety, Y is a linker, Z is an active agent, and n is an integer between 1 and 50, between 2 and 20, for example, between 1 and 5. Each occurrence of X, Y, and Z can be the same or different, e.g., the conjugate can contain more than one type of targeting moiety, more than one type of linker, and/or more than one type of active agent. 
     The conjugate can contain more than one targeting moiety attached to a single active agent. For example, the conjugate can include an active agent with multiple targeting moieties each attached via a different linker. The conjugate can have the structure X-Y-Z-Y-X where each X is a targeting moiety that may be the same or different, each Y is a linker that may be the same or different, and Z is the active agent. 
     The conjugate can contain more than one active agent attached to a single targeting moiety. For example, the conjugate can include a targeting moiety with multiple active agents each attached via a different linker. The conjugate can have the structure Z—Y-X-Y-Z where X is the targeting moiety, each Y is a linker that may be the same or different, and each Z is an active agent that may be the same or different. 
     In some embodiments, the active agent Z is DM1 and the somatostatin receptor binding agent X is selected from somatostatin, cyclo(AA-Tyr-DTrp-Lys-Thr-Phe), vapreotide or TATE. In some embodiments, DM1 is connected to the C-terminus of X with the linker Y. In some embodiments, DM1 is connected to the N-terminus of X with the linker Y. In some embodiments, DM1 is connected to X with the linker Y, wherein the targeting moiety X comprises at least one D-Phe residue and the phenyl ring of the D-Phe residue has been replaced by a group containing linker Y. 
     In some embodiments, cyclo(AA-Tyr-DTrp-Lys-Thr-Phe) is used as a somatostatin receptor targeting moiety. Non-limiting examples of conjugates comprising cyclo(AA-Tyr-DTrp-Lys-Thr-Phe) and DM1 are shown in Table 1 of PCT Application No. PCT/US15/38569 (WO2016/004048) filed Jun. 30, 2015, the contents of which are incorporated herein by reference. 
     In some embodiments, the somatostatin receptor targeting moiety is a peptide and the linker binds to the C-terminus of the somatostatin receptor targeting moiety. In some embodiments, the somatostatin receptor targeting moiety is TATE or a TATE derivative, wherein the linker binds to the C-terminus of TATE or the TATE derivative, referred to as C-terminal TATE-based DM1 conjugate. Non-limiting examples of DM1 conjugates wherein the linker binds to the C-terminus of the somatostatin receptor targeting moiety, wherein the somatostatin receptor targeting moiety is TATE, are shown in Table 2 of PCT Application No. PCT/US15/38569 (WO2016/004048) filed Jun. 30, 2015, the contents of which are incorporated herein by reference. 
     In some embodiments, the conjugate is Conjugate 57 or a pharmaceutically acceptable salt thereof 
     
       
         
         
             
             
         
       
         
         
           
             CAS registry number 1853254-97-3 
             Molecular Formula (free form) C 83 H 109 ClN 14 O 20 S 4    
             Relative Molecular Mass (free form) 1786.55 g/mol 
           
         
       
    
     
       
         
           
               
               
               
               
               
             
               
                   
               
               
                 R 
                 Ar1 
                 Ar2 
                 Linker* 
                 Full Structure 
               
               
                   
               
             
            
               
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     II. Pharmaceutical Formulations 
     In some embodiments, compositions are administered to humans, human patients or subjects. For the purposes of the present disclosure, the phrase “active ingredient” generally refers to the conjugate as described herein. 
     Although the descriptions of pharmaceutical compositions provided herein are principally directed to pharmaceutical compositions which are suitable for administration to humans, it will be understood by the skilled artisan that such compositions are generally suitable for administration to any other animal, e.g., to non-human animals, e.g. non-human mammals. Modification of pharmaceutical compositions suitable for administration to humans in order to render the compositions suitable for administration to various animals is well understood, and the ordinarily skilled veterinary pharmacologist can design and/or perform such modification with merely ordinary, if any, experimentation. Subjects to which administration of the pharmaceutical compositions is contemplated include, but are not limited to, humans and/or other primates; mammals, including commercially relevant mammals such as cattle, pigs, horses, sheep, cats, dogs, mice, and/or rats; and/or birds, including commercially relevant birds such as poultry, chickens, ducks, geese, and/or turkeys. 
     Formulations of the pharmaceutical compositions described herein may be prepared by any method known or hereafter developed in the art of pharmacology. In general, such preparatory methods include the step of bringing the active ingredient into association with an excipient and/or one or more other accessory ingredients, and then, if necessary and/or desirable, dividing, shaping and/or packaging the product into a desired single- or multi-dose unit. 
     A pharmaceutical composition in accordance with the invention may be prepared, packaged, and/or sold in bulk, as a single unit dose, and/or as a plurality of single unit doses. As used herein, a “unit dose” is discrete amount of the pharmaceutical composition comprising a predetermined amount of the active ingredient. The amount of the active ingredient is generally equal to the dosage of the active ingredient which would be administered to a subject and/or a convenient fraction of such a dosage such as, for example, one-half or one-third of such a dosage. 
     Relative amounts of the active ingredient, the pharmaceutically acceptable excipient, and/or any additional ingredients in a pharmaceutical composition in accordance with the invention will vary, depending upon the identity, size, and/or condition of the subject treated and further depending upon the route by which the composition is to be administered. By way of example, the composition may comprise between 0.1% and 100%, e.g., between 0.5 and 50%, between 1-30%, between 5-80%, at least 80% (w/w) active ingredient. 
     The conjugates can be formulated using one or more excipients to: (1) increase stability; (2) permit the sustained or delayed release (e.g., from a depot formulation of the monomaleimide); (3) alter the biodistribution (e.g., target the monomaleimide compounds to specific tissues or cell types); (4) alter the release profile of the monomaleimide compounds in vivo. Non-limiting examples of the excipients include any and all solvents, dispersion media, diluents, or other liquid vehicles, dispersion or suspension aids, surface active agents, isotonic agents, thickening or emulsifying agents, and preservatives. Excipients of the present invention may also include, without limitation, lipidoids, liposomes, lipid nanoparticles, polymers, lipoplexes, core-shell nanoparticles, peptides, proteins, hyaluronidase, nanoparticle mimics and combinations thereof. Accordingly, the formulations of the invention may include one or more excipients, each in an amount that together increases the stability of the monomaleimide compounds. 
     In some embodiments, the pharmaceutical composition comprises the conjugate of the present invention has a pH of about 4.0 to about 5.0. In some embodiments, the pharmaceutical composition comprises acetate buffer (sodium acetate and acetic acid) having a pH of about 4.0 to about 4.8. In some embodiments, the pharmaceutical composition further comprises mannitol and polyoxyl 15 hydroxystearate. 
     In one embodiment, a composition for solution for injection is provided. The solution comprises Conjugate 57, mannitol, Polyoxyl 15 Hydroxystearate, and aqueous acetate buffer. Each dosage unit contains 2.5 mg/mL of Conjugate 57 (free-base), 50 mg/mL mannitol, 20 mg/mL Polyoxyl 15 Hydroxystearate and pH 4.0-4.8 acetate buffer in a stoppered 10 mL clear glass vial. The clear glass vial is stopped with 20 mm FluroTec® gray lyo stoppers, and sealed with 20 mm dark blue flip-off seals. Prior to administration, the solution is diluted with 5% Mannitol Injection USP. The resulting diluted composition can be infused intravenously. 
     Excipients 
     Pharmaceutical formulations may additionally comprise a pharmaceutically acceptable excipient, which, as used herein, includes any and all solvents, dispersion media, diluents, or other liquid vehicles, dispersion or suspension aids, surface active agents, isotonic agents, thickening or emulsifying agents, preservatives, solid binders, lubricants and the like, as suited to the particular dosage form desired. Remington&#39;s The Science and Practice of Pharmacy, 21st Edition, A. R. Gennaro (Lippincott, Williams &amp; Wilkins, Baltimore, Md., 2006; incorporated herein by reference in its entirety) discloses various excipients used in formulating pharmaceutical compositions and known techniques for the preparation thereof. Except insofar as any conventional excipient medium is incompatible with a substance or its derivatives, such as by producing any undesirable biological effect or otherwise interacting in a deleterious manner with any other component(s) of the pharmaceutical composition, its use is contemplated to be within the scope of this invention. 
     In some embodiments, a pharmaceutically acceptable excipient is at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% pure. In some embodiments, an excipient is approved for use in humans and for veterinary use. In some embodiments, an excipient is approved by United States Food and Drug Administration. In some embodiments, an excipient is pharmaceutical grade. In some embodiments, an excipient meets the standards of the United States Pharmacopoeia (USP), the European Pharmacopoeia (EP), the British Pharmacopoeia, and/or the International Pharmacopoeia. 
     Pharmaceutically acceptable excipients used in the manufacture of pharmaceutical compositions include, but are not limited to, inert diluents, dispersing and/or granulating agents, surface active agents and/or emulsifiers, disintegrating agents, binding agents, preservatives, buffering agents, lubricating agents, and/or oils. Such excipients may optionally be included in pharmaceutical compositions. 
     Exemplary diluents include, but are not limited to, calcium carbonate, sodium carbonate, calcium phosphate, dicalcium phosphate, calcium sulfate, calcium hydrogen phosphate, sodium phosphate lactose, sucrose, cellulose, microcrystalline cellulose, kaolin, mannitol, sorbitol, inositol, sodium chloride, dry starch, cornstarch, powdered sugar, etc., and/or combinations thereof. 
     Exemplary granulating and/or dispersing agents include, but are not limited to, potato starch, corn starch, tapioca starch, sodium starch glycolate, clays, alginic acid, guar gum, citrus pulp, agar, bentonite, cellulose and wood products, natural sponge, cation-exchange resins, calcium carbonate, silicates, sodium carbonate, cross-linked poly(vinyl-pyrrolidone) (crospovidone), sodium carboxymethyl starch (sodium starch glycolate), carboxymethyl cellulose, cross-linked sodium carboxymethyl cellulose (croscarmellose), methylcellulose, pregelatinized starch (starch 1500), microcrystalline starch, water insoluble starch, calcium carboxymethyl cellulose, magnesium aluminum silicate (VEEGUM®), sodium lauryl sulfate, quaternary ammonium compounds, etc., and/or combinations thereof. 
     Exemplary surface active agents and/or emulsifiers include, but are not limited to, natural emulsifiers (e.g. acacia, agar, alginic acid, sodium alginate, tragacanth, chondrux, cholesterol, xanthan, pectin, gelatin, egg yolk, casein, wool fat, cholesterol, wax, and lecithin), colloidal clays (e.g. bentonite [aluminum silicate] and VEEGUM® [magnesium aluminum silicate]), long chain amino acid derivatives, high molecular weight alcohols (e.g. stearyl alcohol, cetyl alcohol, oleyl alcohol, triacetin monostearate, ethylene glycol distearate, glyceryl monostearate, and propylene glycol monostearate, polyvinyl alcohol), carbomers (e.g. carboxy polymethylene, polyacrylic acid, acrylic acid polymer, and carboxyvinyl polymer), carrageenan, cellulosic derivatives (e.g. carboxymethylcellulose sodium, powdered cellulose, hydroxymethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methylcellulose, methylcellulose), sorbitan fatty acid esters (e.g. polyoxyethylene sorbitan monolaurate [TWEEN®20], polyoxyethylene sorbitan [TWEENn®60], polyoxyethylene sorbitan monooleate [TWEEN®80], sorbitan monopalmitate [SPAN®40], sorbitan monostearate [SPAN®60], sorbitan tristearate [SPAN®65], glyceryl monooleate, sorbitan monooleate [SPAN®80]), polyoxyethylene esters (e.g. polyoxyethylene monostearate [MYRJ®45], polyoxyethylene hydrogenated castor oil, polyethoxylated castor oil, polyoxymethylene stearate, and SOLUTOL®), sucrose fatty acid esters, polyethylene glycol fatty acid esters (e.g. CREMOPHOR®), polyoxyethylene ethers, (e.g. polyoxyethylene lauryl ether [BRIJ®30]), poly(vinyl-pyrrolidone), diethylene glycol monolaurate, triethanolamine oleate, sodium oleate, potassium oleate, ethyl oleate, oleic acid, ethyl laurate, sodium lauryl sulfate, PLUORINC®F 68, POLOXAMER®188, cetrimonium bromide, cetylpyridinium chloride, benzalkonium chloride, docusate sodium, etc. and/or combinations thereof. 
     Exemplary binding agents include, but are not limited to, starch (e.g. cornstarch and starch paste); gelatin; sugars (e.g. sucrose, glucose, dextrose, dextrin, molasses, lactose, lactitol, mannitol,); natural and synthetic gums (e.g. acacia, sodium alginate, extract of Irish moss, panwar gum, ghatti gum, mucilage of isapol husks, carboxymethylcellulose, methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropyl cellulose, hydroxypropyl methylcellulose, microcrystalline cellulose, cellulose acetate, poly(vinyl-pyrrolidone), magnesium aluminum silicate (Veegum®), and larch arabogalactan); alginates; polyethylene oxide; polyethylene glycol; inorganic calcium salts; silicic acid; polymethacrylates; waxes; water; alcohol; etc.; and combinations thereof. 
     Exemplary preservatives may include, but are not limited to, antioxidants, chelating agents, antimicrobial preservatives, antifungal preservatives, alcohol preservatives, acidic preservatives, and/or other preservatives. Exemplary antioxidants include, but are not limited to, alpha tocopherol, ascorbic acid, acorbyl palmitate, butylated hydroxyanisole, butylated hydroxytoluene, monothioglycerol, potassium metabisulfite, propionic acid, propyl gallate, sodium ascorbate, sodium bisulfite, sodium metabisulfite, and/or sodium sulfite. Exemplary chelating agents include ethylenediaminetetraacetic acid (EDTA), citric acid monohydrate, disodium edetate, dipotassium edetate, edetic acid, fumaric acid, malic acid, phosphoric acid, sodium edetate, tartaric acid, and/or trisodium edetate. Exemplary antimicrobial preservatives include, but are not limited to, benzalkonium chloride, benzethonium chloride, benzyl alcohol, bronopol, cetrimide, cetylpyridinium chloride, chlorhexidine, chlorobutanol, chlorocresol, chloroxylenol, cresol, ethyl alcohol, glycerin, hexetidine, imidurea, phenol, phenoxyethanol, phenylethyl alcohol, phenylmercuric nitrate, propylene glycol, and/or thimerosal. Exemplary antifungal preservatives include, but are not limited to, butyl paraben, methyl paraben, ethyl paraben, propyl paraben, benzoic acid, hydroxybenzoic acid, potassium benzoate, potassium sorbate, sodium benzoate, sodium propionate, and/or sorbic acid. Exemplary alcohol preservatives include, but are not limited to, ethanol, polyethylene glycol, phenol, phenolic compounds, bisphenol, chlorobutanol, hydroxybenzoate, and/or phenylethyl alcohol. Exemplary acidic preservatives include, but are not limited to, vitamin A, vitamin C, vitamin E, beta-carotene, citric acid, acetic acid, dehydroacetic acid, ascorbic acid, sorbic acid, and/or phytic acid. Other preservatives include, but are not limited to, tocopherol, tocopherol acetate, deteroxime mesylate, cetrimide, butylated hydroxyanisol (BHA), butylated hydroxytoluened (BHT), ethylenediamine, sodium lauryl sulfate (SLS), sodium lauryl ether sulfate (SLES), sodium bisulfite, sodium metabisulfite, potassium sulfite, potassium metabisulfite, GLYDANT PLUS®, PHENONIP®, methylparaben, GERMALL®115, GERMABEN®II, NEOLONE™, KATHON™, and/or EUXYL®. 
     Exemplary buffering agents include, but are not limited to, citrate buffer solutions, acetate buffer solutions, phosphate buffer solutions, ammonium chloride, calcium carbonate, calcium chloride, calcium citrate, calcium glubionate, calcium gluceptate, calcium gluconate, D-gluconic acid, calcium glycerophosphate, calcium lactate, propanoic acid, calcium levulinate, pentanoic acid, dibasic calcium phosphate, phosphoric acid, tribasic calcium phosphate, calcium hydroxide phosphate, potassium acetate, potassium chloride, potassium gluconate, potassium mixtures, dibasic potassium phosphate, monobasic potassium phosphate, potassium phosphate mixtures, sodium acetate, sodium bicarbonate, sodium chloride, sodium citrate, sodium lactate, dibasic sodium phosphate, monobasic sodium phosphate, sodium phosphate mixtures, tromethamine, magnesium hydroxide, aluminum hydroxide, alginic acid, pyrogen-free water, isotonic saline, Ringer&#39;s solution, ethyl alcohol, etc., and/or combinations thereof. 
     Exemplary lubricating agents include, but are not limited to, magnesium stearate, calcium stearate, stearic acid, silica, talc, malt, glyceryl behanate, hydrogenated vegetable oils, polyethylene glycol, sodium benzoate, sodium acetate, sodium chloride, leucine, magnesium lauryl sulfate, sodium lauryl sulfate, etc., and combinations thereof. 
     Exemplary oils include, but are not limited to, almond, apricot kernel, avocado, babassu, bergamot, black current seed, borage, cade, camomile, canola, caraway, carnauba, castor, cinnamon, cocoa butter, coconut, cod liver, coffee, corn, cotton seed, emu, eucalyptus, evening primrose, fish, flaxseed, geraniol, gourd, grape seed, hazel nut, hyssop, isopropyl myristate, jojoba, kukui nut, lavandin, lavender, lemon, litsea cubeba, macademia nut, mallow, mango seed, meadowfoam seed, mink, nutmeg, olive, orange, orange roughy, palm, palm kernel, peach kernel, peanut, poppy seed, pumpkin seed, rapeseed, rice bran, rosemary, safflower, sandalwood, sasquana, savoury, sea buckthorn, sesame, shea butter, silicone, soybean, sunflower, tea tree, thistle, tsubaki, vetiver, walnut, and wheat germ oils. Exemplary oils include, but are not limited to, butyl stearate, caprylic triglyceride, capric triglyceride, cyclomethicone, diethyl sebacate, dimethicone 360, isopropyl myristate, mineral oil, octyldodecanol, oleyl alcohol, silicone oil, and/or combinations thereof. 
     Excipients such as cocoa butter and suppository waxes, coloring agents, coating agents, sweetening, flavoring, and/or perfuming agents can be present in the composition, according to the judgment of the formulator. 
     Administration 
     The conjugates of the present invention may be administered by any route which results in a therapeutically effective outcome. These include, but are not limited to enteral, gastroenteral, epidural, oral, transdermal, epidural (peridural), intracerebral (into the cerebrum), intracerebroventricular (into the cerebral ventricles), epicutaneous (application onto the skin), intradermal, (into the skin itself), subcutaneous (under the skin), nasal administration (through the nose), intravenous (into a vein), intraarterial (into an artery), intramuscular (into a muscle), intracardiac (into the heart), intraosseous infusion (into the bone marrow), intrathecal (into the spinal canal), intraperitoneal, (infusion or injection into the peritoneum), intravesical infusion, intravitreal, (through the eye), intracavernous injection, (into the base of the penis), intravaginal administration, intrauterine, extra-amniotic administration, transdermal (diffusion through the intact skin for systemic distribution), transmucosal (diffusion through a mucous membrane), insufflation (snorting), sublingual, sublabial, enema, eye drops (onto the conjunctiva), or in ear drops. In specific embodiments, compositions may be administered in a way which allows them cross the blood-brain barrier, vascular barrier, or other epithelial barrier. 
     The formulations described herein contain an effective amount of conjugates in a pharmaceutical carrier appropriate for administration to an individual in need thereof. The formulations may be administered parenterally (e.g., by injection or infusion). The formulations or variations thereof may be administered in any manner including enterally, topically (e.g., to the eye), or via pulmonary administration. In some embodiments the formulations are administered topically. 
     Dosing 
     The present invention provides methods comprising administering conjugates as described herein to a subject in need thereof. Conjugates as described herein may be administered to a subject using any amount and any route of administration effective for preventing or treating or imaging a disease, disorder, and/or condition (e.g., a disease, disorder, and/or condition relating to working memory deficits). The exact amount required will vary from subject to subject, depending on the species, age, and general condition of the subject, the severity of the disease, the particular composition, its mode of administration, its mode of activity, and the like. 
     Compositions in accordance with the invention are typically formulated in dosage unit form for ease of administration and uniformity of dosage. It will be understood, however, that the total daily usage of the compositions of the present invention may be decided by the attending physician within the scope of sound medical judgment. The specific therapeutically effective, prophylactically effective, or appropriate imaging dose level for any particular patient will depend upon a variety of factors including the disorder being treated and the severity of the disorder; the activity of the specific compound employed; the specific composition employed; the age, body weight, general health, sex and diet of the patient; the time of administration, route of administration, and rate of excretion of the specific compound employed; the duration of the treatment; drugs used in combination or coincidental with the specific compound employed; and like factors well known in the medical arts. 
     In some embodiments, compositions in accordance with the present invention may be administered at dosage levels sufficient to deliver from about 0.0001 mg/kg to about 100 mg/kg, from about 0.001 mg/kg to about 0.05 mg/kg, from about 0.005 mg/kg to about 0.05 mg/kg, from about 0.001 mg/kg to about 0.005 mg/kg, from about 0.05 mg/kg to about 0.5 mg/kg, from about 0.01 mg/kg to about 50 mg/kg, from about 0.1 mg/kg to about 40 mg/kg, from about 0.5 mg/kg to about 30 mg/kg, from about 0.01 mg/kg to about 10 mg/kg, from about 0.1 mg/kg to about 10 mg/kg, or from about 1 mg/kg to about 25 mg/kg, of subject body weight per day, one or more times a day, to obtain the desired therapeutic, diagnostic, prophylactic, or imaging effect. The desired dosage may be delivered three times a day, two times a day, once a day, every other day, every third day, every week, every two weeks, every three weeks, or every four weeks. In some embodiments, the desired dosage may be delivered using multiple administrations (e.g., two, three, four, five, six, seven, eight, nine, ten, eleven, twelve, thirteen, fourteen, or more administrations). When multiple administrations are employed, split dosing regimens such as those described herein may be used. 
     In some embodiments, Conjugate 57 and/or its pharmaceutically acceptable salt is administered at a dosage of between about 1 mg to about 50 mg, such as about 1 mg, 2 mg, 4 mg, 6 mg, 8 mg, 10 mg, 12 mg, 14 mg, 16 mg, 18 mg, 20 mg, 22 mg, 24 mg, 26 mg, 28 mg, 30 mg, 32 mg, 34 mg, 36 mg, 38 mg, 40 mg, 42 mg, 44 mg, 46 mg, 48 mg, or 50 mg. In some embodiments, Conjugate 57 and/or its pharmaceutically acceptable salt is administered at a dosage of from about 18 mg to about 50 mg or about 25 mg to about 50 mg. In some embodiments, Conjugate 57 and/or its pharmaceutically acceptable salt is administered at a dosage of about 25 mg. In some embodiments, Conjugate 57 and/or its pharmaceutically acceptable salt is administered at a dosage of 25 mg. 
     The concentration of the conjugates may be between about 0.01 mg/mL to about 50 mg/mL, about 0.1 mg/mL to about 25 mg/mL, about 0.5 mg/mL to about 10 mg/mL, or about 1 mg/mL to about 5 mg/mL in the pharmaceutical composition. 
     As used herein, a “split dose” is the division of single unit dose or total daily dose into two or more doses, e.g, two or more administrations of the single unit dose. As used herein, a “single unit dose” is a dose of any therapeutic administed in one dose/at one time/single route/single point of contact, i.e., single administration event. As used herein, a “total daily dose” is an amount given or prescribed in 24 hr period. It may be administered as a single unit dose. In one embodiment, the monomaleimide compounds of the present invention are administed to a subject in split doses. The monomaleimide compounds may be formulated in buffer only or in a formulation described herein. 
     Dosage Forms 
     A pharmaceutical composition described herein can be formulated into a dosage form described herein, such as a topical, intranasal, intratracheal, or injectable (e.g., intravenous, intraocular, intravitreal, intramuscular, intracardiac, intraperitoneal, subcutaneous). 
     Liquid Dosage Forms 
     Liquid dosage forms for parenteral administration include, but are not limited to, pharmaceutically acceptable emulsions, microemulsions, solutions, suspensions, syrups, and/or elixirs. In addition to active ingredients, liquid dosage forms may comprise inert diluents commonly used in the art including, but not limited to, water or other solvents, solubilizing agents and emulsifiers such as ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1,3-butylene glycol, dimethylformamide, oils (in particular, cottonseed, groundnut, corn, germ, olive, castor, and sesame oils), glycerol, tetrahydrofurfuryl alcohol, polyethylene glycols and fatty acid esters of sorbitan, and mixtures thereof. In certain embodiments for parenteral administration, compositions may be mixed with solubilizing agents such as CREMOPHOR®, alcohols, oils, modified oils, glycols, polysorbates, cyclodextrins, polymers, and/or combinations thereof. 
     Injectable 
     Injectable preparations, for example, sterile injectable aqueous or oleaginous suspensions may be formulated according to the known art and may include suitable dispersing agents, wetting agents, and/or suspending agents. Sterile injectable preparations may be sterile injectable solutions, suspensions, and/or emulsions in nontoxic parenterally acceptable diluents and/or solvents, for example, a solution in 1,3-butanediol. Among the acceptable vehicles and solvents that may be employed include, but are not limited to, water, Ringer&#39;s solution, U.S.P., and isotonic sodium chloride solution. Sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose any bland fixed oil can be employed including synthetic mono- or diglycerides. Fatty acids such as oleic acid can be used in the preparation of injectables. 
     Injectable formulations can be sterilized, for example, by filtration through a bacterial-retaining filter, and/or by incorporating sterilizing agents in the form of sterile solid compositions which can be dissolved or dispersed in sterile water or other sterile injectable medium prior to use. 
     In order to prolong the effect of an active ingredient, it may be desirable to slow the absorption of the active ingredient from subcutaneous or intramuscular injection. This may be accomplished by the use of a liquid suspension of crystalline or amorphous material with poor water solubility. The rate of absorption of the monomaleimide compounds then depends upon its rate of dissolution which, in turn, may depend upon crystal size and crystalline form. Alternatively, delayed absorption of a parenterally administered monomaleimide compound may be accomplished by dissolving or suspending the monomalimide in an oil vehicle. Injectable depot forms are made by forming microencapsule matrices of the monomaleimide compunds in biodegradable polymers such as polylactide-polyglycolide. Depending upon the ratio of monomaleimide compounds to polymer and the nature of the particular polymer employed, the rate of monomaleimide compound release can be controlled. Examples of other biodegradable polymers include, but are not limited to, poly(orthoesters) and poly(anhydrides). Depot injectable formulations may be prepared by entrapping the monomaleimide compounds in liposomes or microemulsions which are compatible with body tissues. 
     Pulmonary 
     Formulations described herein as being useful for pulmonary delivery may also be used for intranasal delivery of a pharmaceutical composition. Another formulation suitable for intranasal administration may be a coarse powder comprising the active ingredient and having an average particle from about 0.2 μm to 500 μm. Such a formulation may be administered in the manner in which snuff is taken, i.e. by rapid inhalation through the nasal passage from a container of the powder held close to the nose. 
     Formulations suitable for nasal administration may, for example, comprise from about as little as 0.1% (w/w) and as much as 100% (w/w) of active ingredient, and may comprise one or more of the additional ingredients described herein. A pharmaceutical composition may be prepared, packaged, and/or sold in a formulation suitable for buccal administration. Such formulations may, for example, be in the form of tablets and/or lozenges made using conventional methods, and may, for example, contain about 0.1% to 20% (w/w) active ingredient, where the balance may comprise an orally dissolvable and/or degradable composition and, optionally, one or more of the additional ingredients described herein. Alternately, formulations suitable for buccal administration may comprise a powder and/or an aerosolized and/or atomized solution and/or suspension comprising active ingredient. Such powdered, aerosolized, and/or aerosolized formulations, when dispersed, may have an average particle and/or droplet size in the range from about 0.1 nm to about 200 nm, and may further comprise one or more of any additional ingredients described herein. 
     General considerations in the formulation and/or manufacture of pharmaceutical agents may be found, for example, in Remington: The Science and Practice of Pharmacy 21st ed., Lippincott Williams &amp; Wilkins, 2005 (incorporated herein by reference in its entirety). Coatings or Shells 
     Solid dosage forms of tablets, dragees, capsules, pills, and granules can be prepared with coatings and shells such as enteric coatings and other coatings well known in the pharmaceutical formulating art. They may optionally comprise opacifying agents and can be of a composition that they release the active ingredient(s) only, or preferentially, in a certain part of the intestinal tract, optionally, in a delayed manner. Examples of embedding compositions which can be used include polymeric substances and waxes. Solid compositions of a similar type may be employed as fillers in soft and hard-filled gelatin capsules using such excipients as lactose or milk sugar as well as high molecular weight polyethylene glycols and the like. 
     III. Methods of Using the Conjugates 
     The conjugates can be administered to treat any hyperproliferative disease, metabolic disease, infectious disease, or cancer, as appropriate. The formulations can be used for immunization. Formulations may be administered by injection, orally, or topically, typically to a mucosal surface (lung, nasal, oral, buccal, sublingual, vaginally, rectally) or to the eye (intraocularly or transocularly). 
     In various embodiments, methods for treating a subject having a cancer are provided, wherein the method comprises administering a therapeutically-effective amount of the conjugates, as described herein, to a subject having a cancer, suspected of having cancer, or having a predisposition to a cancer. According to the present invention, cancer embraces any disease or malady characterized by uncontrolled cell proliferation, e.g., hyperproliferation. Cancers may be characterized by tumors, e.g., solid tumors or any neoplasm. 
     In some embodiments, the cancer is a solid tumor. Large drug molecules have limited penetration in solid tumors. The penetration of large drug molecules is slow. On the other hand, small molecules such as conjugates of the present invention may penetrate solid tumors rapidly and more deeply. Regarding penetration depth of the drugs, larger molecules penetrate less, despite having more durable pharmacokinectics. Small molecules such as conjugates of the present invention penetrate deeper. Dreher et al. (Dreher et al., JNCI, vol. 98(5):335 (2006), the contents of which are incorporated herein by reference in their entirety) studied penetration of dextrans with different sizes into a tumor xenograft. As summarized in  FIG. 6  (see  FIG. 1  of the present application) and Table 1 of Dreher, Dextrans with a molecular weight of 3.3 kDa or 10 kDa showed rapid deep penetration into the tumor tissue (&gt;35 um from the vascular surface of the tumor). However, 40 kDa, 70 kDa or 2 mDa sized dextrans penetrated much less than the 3.3 kDa or 10 kDa dextran. The 70 kDa dextran reached only about 15 um from the vascular surface of the tumor. Conjugates of the present invention have a molecule weight comparable to the 3.3 kDa and 10 kDa dextrans, while antibody drug conjugates have a molecule weight at least as big as the 70 kDa dextran. Therefore, conjugates of the present invention may penetrate deep and rapidly into the core/center of the solid tumor. 
     In one embodiment, conjugates of the present invention reach at least about 25 μm, about 30 μm, about 35 μm, about 40 μm, about 45 μm, about 50 μm, about 75 μm, about 100 μm, about 150 μm, about 200 μm, about 250 μm, about 300 μm, about 400 μm, about 500 μm, about 600 μm, about 700 μm, about 800 μm, about 900 μm, about 1000 μm, about 1100 μm, about 1200 μm, about 1300 μm, about 1400 μm or about 1500 μm into the solid tumor from the vascular surface of the tumor. Zero distance is defined as the vascular surface of the tumor, and every distance greater than zero is defined as the distance measured in three dimensions to the nearest vascular surface. 
     In another embodiment, conjugates of the present invention penetrate to the core of the tumor. “Core” of the tumor, as used herein, refers to the central area of the tumor. The distance from any part of the core area of the tumor to the vascular surface of the tumor is between about 30% to about 50% of the length or width of the tumor. The distance from any part of the core area of the tumor to the center point of the tumor is less than about 20% of the length or width of the tumor. The core area of the tumor is roughly the center ⅓ of the tumor. 
     In another embodiment, conjugates of the present invention penetrate to the middle of the solid tumor. “Middle” of the tumor, as sued herein, refers to the middle area of the tumor. The distance from any part of the middle area of the tumor to the vascular surface of the tumor is between about 15% and about 30% of the length or the width of the tumor. The distance from any part of the middle area of the tumor to the center point of the tumor is between about 20% to about 35% of the length or width of the tumor. The middle area of the tumor is roughly between the center ⅓ of the tumor and the outer ⅓ of the tumor. 
     In some embodiments, the subject may be otherwise free of indications for treatment with the conjugates. In some embodiments, methods include use of cancer cells, including but not limited to mammalian cancer cells. In some instances, the mammalian cancer cells are human cancer cells. 
     In some embodiments, the conjugates have been found to inhibit cancer and/or tumor growth. They may also reduce, including cell proliferation, invasiveness, and/or metastasis, thereby rendering them useful for the treatment of a cancer. 
     In some embodiments, the conjugates may be used to prevent the growth of a tumor or cancer, and/or to prevent the metastasis of a tumor or cancer. In some embodiments, compositions of the present teachings may be used to shrink or destroy a cancer. 
     In some embodiments, the conjugates are useful for inhibiting proliferation of a cancer cell. In some embodiments, the conjugates are useful for inhibiting cellular proliferation, e.g., inhibiting the rate of cellular proliferation, preventing cellular proliferation, and/or inducing cell death. In general, the conjugates can inhibit cellular proliferation of a cancer cell or both inhibiting proliferation and/or inducing cell death of a cancer cell. In some embodiments, cell proliferation is reduced by at least about 25%, about 50%, about 75%, or about 90% after treatment with the conjguates compared with cells with no treatment. In some embodiments, cell cycle arrest marker phospho histone H3 (PH3 or PHH3) is increased by at least about 50%, about 75%, about 100%, about 200%, about 400% or about 600% after treatment with the conjguates compared with cells with no treatment. In some embodiments, cell apoptosis marker cleaved caspase-3 (CC3) is increased by at least 50%, about 75%, about 100%, about 200%, about 400% or about 600% after treatment with the conjguates compared with cells with no treatment. 
     Furthermore, in some embodiments, the conjugates are effective for inhibiting tumor growth, whether measured as a net value of size (weight, surface area or volume) or as a rate over time, in multiple types of tumors. 
     In some embodiments, the size of a tumor is reduced by about 60% or more after treatment with the conjugates. In some embodiments, the size of a tumor is reduced by at least about 20%, at least about 30%, at least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, at least about 100%, by a measure of weight, and/or area and/or volume. 
     The cancers treatable by methods of the present teachings generally occur in mammals. Mammals include, for example, humans, non-human primates, dogs, cats, rats, mice, rabbits, ferrets, guinea pigs, horses, pigs, sheep, goats, and cattle. In various embodiments, the cancer is lung cancer, breast cancer, e.g., mutant BRCA1 and/or mutant BRCA2 breast cancer, non-BRCA-associated breast cancer, colorectal cancer, ovarian cancer, pancreatic cancer, colorectal cancer, bladder cancer, prostate cancer, cervical cancer, renal cancer, leukemia, central nervous system cancers, myeloma, melanoma, lymphoma, meningioma, and nasopharyngeal carcinoma. 
     In some embodiments, the cancer is a neuroendocrine cancer such as but not limited to small cell lung cancer (SCLC), adrenal medullary tumors (e.g., pheochromocytoma, neuroblastoma, ganglioneuroma, or paraganglioma), gastroenteropancreatic neuroendocrine tumors (e.g., carcinoids, gastrinoma, glucagonoma, vasoactive intestinal polypeptide-secreting tumor, pancreatic polypeptide-secreting tumor, or nonfunctioning gastroenteropancreatic tumors), meduallary thyroid cancer, Merkel cell tumor of the skin, pituitary adenoma, and pancreatic cancer. The somatostain receptor SSTR2 is over expressed on 50-90% of neuroendocrine cancers. In some embodiments, the neuroendocrine cancer is a primary neuroendocrine cancer. In some embodiments, the neuroendocrine cancer is a neuroendocrine metastatsis. Neuroendocrine metastatis may be in liver, lung, bone, or brain of a subject. In certain embodiments, the cancer is brain cancer, human lung carcinoma, ovarian cancer, pancreatic cancer or colorectal cancer. 
     In one embodiment, the conjugates or formulations containing the conjugates are used to treat small cell lung cancer. About 12%-15% of patients having lung cancer have small cell lung cancer. Survival in metastatic small cell lung caner is poor. Survival rate is below 5% five years after diagnosis. US incidence of small cell lung cancer is about 26K-30K. Among these patients, about 40%-80% are SSTR2 positive. 
     In some embodiments, the conjugates or formulations containing the conjugates are used to treat paitents with tumors that express or over-express the somatostatn receptor. Such patients can be identified with any method known in the art, such as but not limted to using a radionuclide imaging agent, a radiolabeled somatostatin analog imaging agent, SSTR scintigraphy or SSTR positron emission tomography (PET). In one embodiment, 111Indium (Indium111)-labeled pentetreotide scintigraphy (OctreoScan™) is used to identify patients with SSTR-expressing tumors. In another embodiment, a 68Ga conjugate such as 68Ga-DOTA-TATE, 68Ga-DOTA-TOC, or 68Ga-DOTA-NOC is used in PET imaging to identify patients with SSTR-expressing tumors. Patients who show positive scan results detected with Indium111-labeled pentetreotide scintigraphy are treated with the conjguates. 
     In one embodiment, the conjugates or formulations containing the conjugates are used to treat pateints having a histologically proven locally advanced or metastatic high grade neuroendocrine carcinoma (NEC). In some embodiments, the patients may have small cell and large cell neuroendocrine carcinoma of unknown primary or any extrapulmonary site. In some embodiments, the pateints may have well differentiated G3 neuroendocrine neoplasms if Ki-67&gt;30%. In some embodiments, the pateints may have neuroendocrine prostate cancer (de novo or treatment-emergent) of prostate if small cell or large cell histology. In some embodiments, the patients may have mixed tumors, e.g. mixed adenoneuroendocrine carcinoma (MANEC) or mixed squamous or acinar cell NEC if the high grade (small or large cell) NEC component comprises &gt;50% of the original sample or subsequent biopsy. In some embodiments, the patients may have castrate resistant prostate cancer (CRPC). In some embodiments, patients may be selected or stratified by having, or not having, any of the foregoing conditions. 
     In some embodiments, Conjugate 57 or its pharmaceutically acceptable salt is administered to patients diagnosed with pancreatic cancer, gastrointestinal (GI) cancer (such as small intestine cancer, stomach cancer, rectum cancer, ileum cancer, colon cancer, small bowel cancer, large bowel cancer, gastric cancer, etc.), lung cancer (such as large-cell neuroendocrine carcinoma (LCNEC) of the lung, small cell lung cancer (SCLC), etc.), or pheochromocytoma. In some embodiments, patients treated may have, or not have, been diagnosed with any of the foregoing conditions prior to such treatment. 
     In some embodiments, the patients have a metastatic cancer. In some embodiments, the patients have metastasis to lymph nodes, liver, lung, peritoneum, back, bone, soft tissues outside of uterus, kidney, or vertebral column. In some embodiments, patients treated may have, or not have, been diagnosed with any of the foregoing conditions prior to such treatment. 
     In some embodiments, the patients have had prior cancer treatment therapies. In some embodiments, the patients have previously been treated with lancreotide, mTOR kinase inhibitor, Lutathera (a lutetium-177 (Lu-177) labeled somatostatin analogue peptide), sunitinib, cyclophosphamide, vincristine, dacarbazine, octreotide, carbo, streptozocin, a FOLFIRI therapy (a combination therapy comprising folinic acid (e.g., leucovorin), fluorouracil (5-FU), and irinotecan (e.g., Camptosar)). 
     In some embodiments, the patients are male. In some embodiments, the patients are female. In some embodiments, the patients are at least 18 years old. In some embodiments, the patients are at least 40 years old. In some embodiments, the pateints are at least 60 years old. 
     A feature of conjugates is relatively low toxicity to an organism while maintaining efficacy at inhibiting, e.g. slowing or stopping tumor growth. As used herein, “toxicity” refers to the capacity of a substance or composition to be harmful or poisonous to a cell, tissue organism or cellular environment. Low toxicity refers to a reduced capacity of a substance or composition to be harmful or poisonous to a cell, tissue organism or cellular environment. Such reduced or low toxicity may be relative to a standard measure, relative to a treatment or relative to the absence of a treatment. For example, the conjugates may have lower toxicity than the active agent moiety Z administered alone. For conjugates comprsing DM1, their toxicity is lower than DM1 administered alone. 
     Toxicity may further be measured relative to a subject&#39;s weight loss where weight loss over 15%, over 20% or over 30% of the body weight is indicative of toxicity. Other metrics of toxicity may also be measured such as patient presentation metrics including lethargy and general malaiase. Neutropenia, thrombopenia, white blood cell (WBC) count, complete blood cell (CBC) count may also be metrics of toxicity. Pharmacologic indicators of toxicity include elevated aminotransferases (AST/ALT) levels, neurotoxicity, kidney damage, GI damage and the like. In one embodiment, the conjugates do not cause a significant change of a subject&#39;s body weight. The body weight loss of a subject is less about 30%, about 20%, about 15%, about 10%, or about 5% after treatment with the conjguates. In another embodiment, the conjugates do not cause a significant increase of a subject&#39;s AST/ALT levels. The AST or ALT level of a subject is increased by less than about 30%, about 20%, about 15%, about 10%, or about 5% after treatment with the conjugates. In yet another embodiment, the conjugates do not cause a significant change of a subject&#39;s CBC or WBC count after treatment with conjugates of the present invention. The CBC or WBC level of a subject is decreased by less than about 30%, about 20%, about 15%, about 10%, or about 5% after treatment with the conjugates. 
     In some embodiments, Conjugate 57 is administered to a patient and any one or more of white blood cells (WBC), red blood cells (RBC), hemoglobin, platelets, neutrophils, lymphocytes, blood urea nitrogen (BUN), creatinine, glucose, albumin, total protein, calcium levels, magnesium levels, alkaline phosphatase, total bilirubin, direct bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), amylase, lipase, international normalized ratio (INR), the prothrombin time (PT), and/or activated partial thromboplastin time (aPTT) of the patient are measured. 
     In some embodiments, the treatment-related adverse effects (AE) of a pharmaceutical composition comprising Conjugate 57 may include nausea, fatigue, increased alanine aminotransferase, constipation, diarrhea, increased aspartate aminotransferase, pyrexia, abdominal distension, abdominal pain, anaemia, arthralgia, increased blood alkaline phosphatase, increased blood creatinine, decreased appetite, dyspepsia, hypertension, hypoalbuminaemia, hypotension, insomnia, increased lipase, pain in extremity, paraesthesia, pelvic pain, and/or urinary tract infection. 
     In some embodiments, less than 30% of the patient population has any one or more treatment-related adverse effects. In some embodiments, a single patient experiences treatment-related adverse effects in less 30% of the whole treatment time. 
     In some embodiments, the patients treated with Conjguate 57 have lower, reduced or no circulating tumor cells. 
     In some embodiments, Conjugate 57 has a half life of between about 1.0 to about 2.5 hours, e.g., about 1.5 hours, 1.6 hours, 1.7 hours, 1.8 hours, 1.9 hours or 2.0 hours, in a patient. 
     In some embodiments, patients receive Conjugate 57 treatment every 3 weeks for 3 weeks, 6 weeks, 9 weeks, 12 weeks, 15 weeks, 18 weeks, 21 weeks, 24 weeks, 27 weeks, 30 weeks, 33 weeks, 36 weeks, 39 weeks, 42 weeks, 45 weeks, 48 weeks, 51 weeks, 54 weeks, 57 weeks, 60 weeks, 63 weeks, 66 weeks, 69 weeks, 72 weeks, 75 weeks, 78 weeks, 81 weeks, 84 weeks, 87 weeks, 90 weeks, 93 weeks, 96 weeks, or 99 weeks. In some embodiments, patients receive Conjugate 57 treatment for at least 15 weeks, at least 30 weeks, at least 45 weeks, or at least 60 weeks. 
     The conjugates or formulations containing the conjugates as described herein can be used for the selective tissue delivery of a therapeutic, prophylactic, or diagnostic agent to an individual or patient in need thereof. For example, DM1 conjugates are used to deliver DM1 to selective tissues. These tissues may be tumor tissues. Dosage regimens may be adjusted to provide the optimum desired response (e.g., a therapeutic or prophylactic response). For example, a single bolus may be administered, several divided doses may be administered over time or the dose may be proportionally reduced or increased as indicated by the exigencies of the therapeutic situation. Dosage unit form as used herein refers to physically discrete units suited as unitary dosages for the mammalian subjects to be treated; each unit containing a predetermined quantity of active compound calculated to produce the desired therapeutic. 
     IV. Kits and Devices 
     The invention provides a variety of kits and devices for conveniently and/or effectively carrying out methods of the present invention. Typically kits will comprise sufficient amounts and/or numbers of components to allow a user to perform multiple treatments of a subject(s) and/or to perform multiple experiments. 
     In one embodiment, the present invention provides kits for inhibiting tumor cell growth in vitro or in vivo, comprising a conjugate the present invention or a combination of conjugates of the present invention, optionally in combination with any other active agents. 
     The kit may further comprise packaging and instructions and/or a delivery agent to form a formulation composition. The delivery agent may comprise a saline, a buffered solution, or any delivery agent disclosed herein. The amount of each component may be varied to enable consistent, reproducible higher concentration saline or simple buffer formulations. The components may also be varied in order to increase the stability of the conjugates in the buffer solution over a period of time and/or under a variety of conditions. 
     The present invention provides for devices which may incorporate conjugates of the present invention. These devices contain in a stable formulation available to be immediately delivered to a subject in need thereof, such as a human patient. In some embodiments, the subject has cancer. 
     Non-limiting examples of the devices include a pump, a catheter, a needle, a transdermal patch, a pressurized olfactory delivery device, iontophoresis devices, multi-layered microfluidic devices. The devices may be employed to deliver conjugates of the present invention according to single, multi- or split-dosing regiments. The devices may be employed to deliver conjugates of the present invention across biological tissue, intradermal, subcutaneously, or intramuscularly. 
     V. Definitions 
     The term “compound”, as used herein, is meant to include all stereoisomers, geometric isomers, tautomers, and isotopes of the structures depicted. In the present application, compound is used interechangably with conjugate. Therefore, conjugate, as used herein, is also meant to include all stereoisomers, geometric isomers, tautomers, and isotopes of the structures depicted. 
     The compounds described herein can be asymmetric (e.g., having one or more stereocenters). All stereoisomers, such as enantiomers and diastereomers, are intended unless otherwise indicated. Compounds of the present disclosure that contain asymmetrically substituted carbon atoms can be isolated in optically active or racemic forms. Methods on how to prepare optically active forms from optically active starting materials are known in the art, such as by resolution of racemic mixtures or by stereoselective synthesis. Many geometric isomers of olefins, C═N double bonds, and the like can also be present in the compounds described herein, and all such stable isomers are contemplated in the present disclosure. Cis and trans geometric isomers of the compounds of the present disclosure are described and may be isolated as a mixture of isomers or as separated isomeric forms. 
     Compounds of the present disclosure also include tautomeric forms. Tautomeric forms result from the swapping of a single bond with an adjacent double bond and the concomitant migration of a proton. Tautomeric forms include prototropic tautomers which are isomeric protonation states having the same empirical formula and total charge. Examples prototropic tautomers include ketone-enol pairs, amide-imidic acid pairs, lactam-lactim pairs, amide-imidic acid pairs, enamine-imine pairs, and annular forms where a proton can occupy two or more positions of a heterocyclic system, such as, 1H- and 3H-imidazole, 1H-, 2H- and 4H-1,2,4-triazole, 1H- and 2H-isoindole, and 1H- and 2H-pyrazole. Tautomeric forms can be in equilibrium or sterically locked into one form by appropriate substitution. 
     Compounds of the present disclosure also include all of the isotopes of the atoms occurring in the intermediate or final compounds. “Isotopes” refers to atoms having the same atomic number but different mass numbers resulting from a different number of neutrons in the nuclei. For example, isotopes of hydrogen include tritium and deuterium. 
     The compounds and salts of the present disclosure can be prepared in combination with solvent or water molecules to form solvates and hydrates by routine methods. 
     The terms “subject” or “patient”, as used herein, refer to any organism to which the conjugates may be administered, e.g., for experimental, therapeutic, diagnostic, and/or prophylactic purposes. Typical subjects include animals (e.g., mammals such as mice, rats, rabbits, guinea pigs, cattle, pigs, sheep, horses, dogs, cats, hamsters, lamas, non-human primates, and humans). 
     The terms “treating” or “preventing”, as used herein, can include preventing a disease, disorder or condition from occurring in an animal that may be predisposed to the disease, disorder and/or condition but has not yet been diagnosed as having the disease, disorder or condition; inhibiting the disease, disorder or condition, e.g., impeding its progress; and relieving the disease, disorder, or condition, e.g., causing regression of the disease, disorder and/or condition. Treating the disease, disorder, or condition can include ameliorating at least one symptom of the particular disease, disorder, or condition, even if the underlying pathophysiology is not affected, such as treating the pain of a subject by administration of an analgesic agent even though such agent does not treat the cause of the pain. 
     A “target”, as used herein, shall mean a site to which targeted constructs bind. A target may be either in vivo or in vitro. In certain embodiments, a target may be cancer cells found in leukemias or tumors (e.g., tumors of the brain, lung (small cell and non-small cell), ovary, prostate, breast and colon as well as other carcinomas and sarcomas). In still other embodiments, a target may refer to a molecular structure to which a targeting moiety or ligand binds, such as a hapten, epitope, receptor, dsDNA fragment, carbohydrate or enzyme. A target may be a type of tissue, e.g., neuronal tissue, intestinal tissue, pancreatic tissue, liver, kidney, prostate, ovary, lung, bone marrow, or breast tissue. 
     The “target cells” that may serve as the target for the method or conjugates, are generally animal cells, e.g., mammalian cells. The present method may be used to modify cellular function of living cells in vitro, i.e., in cell culture, or in vivo, in which the cells form part of or otherwise exist in animal tissue. Thus, the target cells may include, for example, the blood, lymph tissue, cells lining the alimentary canal, such as the oral and pharyngeal mucosa, cells forming the villi of the small intestine, cells lining the large intestine, cells lining the respiratory system (nasal passages/lungs) of an animal (which may be contacted by inhalation of the subject invention), dermal/epidermal cells, cells of the vagina and rectum, cells of internal organs including cells of the placenta and the so-called blood/brain barrier, etc. In general, a target cell expresses at least one type of SSTR. In some embodiments, a target cell can be a cell that expresses an SSTR and is targeted by a conjugate described herein, and is near a cell that is affected by release of the active agent of the conjugate. For example, a blood vessel expressing an SSTR that is in proximity to a tumor may be the target, while the active agent released at the site will affect the tumor. 
     The term “therapeutic effect” is art-recognized and refers to a local or systemic effect in animals, particularly mammals, and more particularly humans caused by a pharmacologically active substance. The term thus means any substance intended for use in the diagnosis, cure, mitigation, treatment or prevention of disease, disorder or condition in the enhancement of desirable physical or mental development and conditions in an animal, e.g., a human. 
     The term “modulation” is art-recognized and refers to up regulation (i.e., activation or stimulation), down regulation (i.e., inhibition or suppression) of a response, or the two in combination or apart. The modulation is generally compared to a baseline or reference that can be internal or external to the treated entity. 
     “Parenteral administration”, as used herein, means administration by any method other than through the digestive tract (enteral) or non-invasive topical routes. For example, parenteral administration may include administration to a patient intravenously, intradermally, intraperitoneally, intrapleurally, intratracheally, intraossiously, intracerebrally, intrathecally, intramuscularly, subcutaneously, subjunctivally, by injection, and by infusion. 
     “Topical administration”, as used herein, means the non-invasive administration to the skin, orifices, or mucosa. Topical administration can be delivered locally, i.e., the therapeutic can provide a local effect in the region of delivery without systemic exposure or with minimal systemic exposure. Some topical formulations can provide a systemic effect, e.g., via adsorption into the blood stream of the individual. Topical administration can include, but is not limited to, cutaneous and transdermal administration, buccal administration, intranasal administration, intravaginal administration, intravesical administration, ophthalmic administration, and rectal administration. 
     “Enteral administration”, as used herein, means administration via absorption through the gastrointestinal tract. Enteral administration can include oral and sublingual administration, gastric administration, or rectal administration. 
     “Pulmonary administration”, as used herein, means administration into the lungs by inhalation or endotracheal administration. As used herein, the term “inhalation” refers to intake of air to the alveoli. The intake of air can occur through the mouth or nose. 
     The terms “sufficient” and “effective”, as used interchangeably herein, refer to an amount (e.g., mass, volume, dosage, concentration, and/or time period) needed to achieve one or more desired result(s). A “therapeutically effective amount” is at least the minimum concentration required to effect a measurable improvement or prevention of at least one symptom or a particular condition or disorder, to effect a measurable enhancement of life expectancy, or to generally improve patient quality of life. The therapeutically effective amount is thus dependent upon the specific biologically active molecule and the specific condition or disorder to be treated. Therapeutically effective amounts of many active agents, such as antibodies, are known in the art. The therapeutically effective amounts of compounds and compositions described herein, e.g., for treating specific disorders may be determined by techniques that are well within the craft of a skilled artisan, such as a physician. 
     The terms “bioactive agent” and “active agent”, as used interchangeably herein, include, without limitation, physiologically or pharmacologically active substances that act locally or systemically in the body. A bioactive agent is a substance used for the treatment (e.g., therapeutic agent), prevention (e.g., prophylactic agent), diagnosis (e.g., diagnostic agent), cure or mitigation of disease or illness, a substance which affects the structure or function of the body, or pro-drugs, which become biologically active or more active after they have been placed in a predetermined physiological environment. 
     The term “prodrug” refers to an agent, including a small organic molecule, peptide, nucleic acid or protein, that is converted into a biologically active form in vitro and/or in vivo. Prodrugs can be useful because, in some situations, they may be easier to administer than the parent compound (the active compound). For example, a prodrug may be bioavailable by oral administration whereas the parent compound is not. The prodrug may also have improved solubility in pharmaceutical compositions compared to the parent drug. A prodrug may also be less toxic than the parent. A prodrug may be converted into the parent drug by various mechanisms, including enzymatic processes and metabolic hydrolysis. Harper, N.J. (1962) Drug Latentiation in Jucker, ed.  Progress in Drug Research,  4:221-294; Morozowich et al. (1977) Application of Physical Organic Principles to Prodrug Design in E. B. Roche ed.  Design of Biopharmaceutical Properties through Prodrugs and Analogs , APhA; Acad. Pharm. Sci.; E. B. Roche, ed. (1977)  Bioreversible Carriers in Drug in Drug Design, Theory and Application , APhA; H. Bundgaard, ed. (1985)  Design of Prodrugs , Elsevier; Wang et al. (1999) Prodrug approaches to the improved delivery of peptide drug, Curr. Pharm. Design. 5(4):265-287; Pauletti et al. (1997) Improvement in peptide bioavailability: Peptidomimetics and Prodrug Strategies, Adv. Drug. Delivery Rev. 27:235-256; Mizen et al. (1998). The Use of Esters as Prodrugs for Oral Delivery of β-Lactam antibiotics, Pharm. Biotech. 11:345-365; Gaignault et al. (1996) Designing Prodrugs and Bioprecursors I. Carrier Prodrugs, Pract. Med. Chem. 671-696; M. Asgharnejad (2000). Improving Oral Drug Transport Via Prodrugs, in G. L. Amidon, P. I. Lee and E. M. Topp, Eds.,  Transport Processes in Pharmaceutical Systems , Marcell Dekker, p. 185-218; Balant et al. (1990) Prodrugs for the improvement of drug absorption via different routes of administration,  Eur. J. Drug Metab. Pharmacokinet.,  15(2): 143-53; Balimane and Sinko (1999). Involvement of multiple transporters in the oral absorption of nucleoside analogues,  Adv. Drug Delivery Rev.,  39(1-3):183-209; Browne (1997). Fosphenytoin (Cerebyx),  Clin. Neuropharmacol.  20(1): 1-12; Bundgaard (1979). Bioreversible derivatization of drugs—principle and applicability to improve the therapeutic effects of drugs,  Arch. Pharm. Chemi.  86(1): 1-39; H. Bundgaard, ed. (1985)  Design of Prodrugs , New York: Elsevier; Fleisher et al. (1996) Improved oral drug delivery: solubility limitations overcome by the use of prodrugs,  Adv. Drug Delivery Rev.  19(2): 115-130; Fleisher et al. (1985) Design of prodrugs for improved gastrointestinal absorption by intestinal enzyme targeting,  Methods Enzymol.  112: 360-81; Farquhar D, et al. (1983) Biologically Reversible Phosphate-Protective Groups,  J. Pharm. Sci.,  72(3): 324-325; Han, H. K. et al. (2000) Targeted prodrug design to optimize drug delivery,  AAPS PharmSci.,  2(1): E6; Sadzuka Y. (2000) Effective prodrug liposome and conversion to active metabolite,  Curr. Drug Metab.,  1(1):31-48; D. M. Lambert (2000) Rationale and applications of lipids as prodrug carriers,  Eur. J. Pharm. Sci.,  11 Suppl. 2:S15-27; Wang, W. et al. (1999) Prodrug approaches to the improved delivery of peptide drugs.  Curr. Pharm. Des.,  5(4):265-87. 
     The term “biocompatible”, as used herein, refers to a material that along with any metabolites or degradation products thereof that are generally non-toxic to the recipient and do not cause any significant adverse effects to the recipient. Generally speaking, biocompatible materials are materials which do not elicit a significant inflammatory or immune response when administered to a patient. 
     The term “biodegradable” as used herein, generally refers to a material that will degrade or erode under physiologic conditions to smaller units or chemical species that are capable of being metabolized, eliminated, or excreted by the subject. The degradation time is a function of composition and morphology. Degradation times can be from hours to weeks. 
     The term “pharmaceutically acceptable”, as used herein, refers to compounds, materials, compositions, and/or dosage forms that are, within the scope of sound medical judgment, suitable for use in contact with the tissues of human beings and animals without excessive toxicity, irritation, allergic response, or other problems or complications commensurate with a reasonable benefit/risk ratio, in accordance with the guidelines of agencies such as the U.S. Food and Drug Administration. A “pharmaceutically acceptable carrier”, as used herein, refers to all components of a pharmaceutical formulation that facilitate the delivery of the composition in vivo. Pharmaceutically acceptable carriers include, but are not limited to, diluents, preservatives, binders, lubricants, disintegrators, swelling agents, fillers, stabilizers, and combinations thereof. 
     The term “molecular weight”, as used herein, generally refers to the mass or average mass of a material. If a polymer or oligomer, the molecular weight can refer to the relative average chain length or relative chain mass of the bulk polymer. In practice, the molecular weight of polymers and oligomers can be estimated or characterized in various ways including gel permeation chromatography (GPC) or capillary viscometry. GPC molecular weights are reported as the weight-average molecular weight (Mw) as opposed to the number-average molecular weight (Mn). Capillary viscometry provides estimates of molecular weight as the inherent viscosity determined from a dilute polymer solution using a particular set of concentration, temperature, and solvent conditions. 
     The term “small molecule”, as used herein, generally refers to an organic molecule that is less than 2000 g/mol in molecular weight, less than 1500 g/mol, less than 1000 g/mol, less than 800 g/mol, or less than 500 g/mol. Small molecules are non-polymeric and/or non-oligomeric. 
     The terms “polypeptide,” “peptide” and “protein” generally refer to a polymer of amino acid residues. As used herein, the term also applies to amino acid polymers in which one or more amino acids are chemical analogs or modified derivatives of corresponding naturally-occurring amino acids or are unnatural amino acids. The term “protein”, as generally used herein, refers to a polymer of amino acids linked to each other by peptide bonds to form a polypeptide for which the chain length is sufficient to produce tertiary and/or quaternary structure. The term “protein” excludes small peptides by definition, the small peptides lacking the requisite higher-order structure necessary to be considered a protein. 
     The terms “nucleic acid,” “polynucleotide,” and “oligonucleotide” are used interchangeably to refer to a deoxyribonucleotide or ribonucleotide polymer, in linear or circular conformation, and in either single- or double-stranded form. These terms are not to be construed as limiting with respect to the length of a polymer. The terms can encompass known analogs of natural nucleotides, as well as nucleotides that are modified in the base, sugar and/or phosphate moieties (e.g., phosphorothioate backbones). In general and unless otherwise specified, an analog of a particular nucleotide has the same base-pairing specificity; i.e., an analog of A will base-pair with T. The term “nucleic acid” is a term of art that refers to a string of at least two base-sugar-phosphate monomeric units. Nucleotides are the monomeric units of nucleic acid polymers. The term includes deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) in the form of a messenger RNA, antisense, plasmid DNA, parts of a plasmid DNA or genetic material derived from a virus. An antisense nucleic acid is a polynucleotide that interferes with the expression of a DNA and/or RNA sequence. The term nucleic acids refers to a string of at least two base-sugar-phosphate combinations. Natural nucleic acids have a phosphate backbone. Artificial nucleic acids may contain other types of backbones, but contain the same bases as natural nucleic acids. The term also includes PNAs (peptide nucleic acids), phosphorothioates, and other variants of the phosphate backbone of native nucleic acids. 
     A “functional fragment” of a protein, polypeptide or nucleic acid is a protein, polypeptide or nucleic acid whose sequence is not identical to the full-length protein, polypeptide or nucleic acid, yet retains at least one function as the full-length protein, polypeptide or nucleic acid. A functional fragment can possess more, fewer, or the same number of residues as the corresponding native molecule, and/or can contain one or more amino acid or nucleotide substitutions. Methods for determining the function of a nucleic acid (e.g., coding function, ability to hybridize to another nucleic acid) are well-known in the art. Similarly, methods for determining protein function are well-known. For example, the DNA binding function of a polypeptide can be determined, for example, by filter-binding, electrophoretic mobility shift, or immunoprecipitation assays. DNA cleavage can be assayed by gel electrophoresis. The ability of a protein to interact with another protein can be determined, for example, by co-immunoprecipitation, two-hybrid assays or complementation, e.g., genetic or biochemical. See, for example, Fields et al. (1989) Nature 340:245-246; U.S. Pat. No. 5,585,245 and PCT WO 98/44350. 
     As used herein, the term “linker” refers to a carbon chain that can contain heteroatoms (e.g., nitrogen, oxygen, sulfur, etc.) and which may be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50 atoms long. Linkers may be substituted with various substituents including, but not limited to, hydrogen atoms, alkyl, alkenyl, alkynl, amino, alkylamino, dialkylamino, trialkylamino, hydroxyl, alkoxy, halogen, aryl, heterocyclic, aromatic heterocyclic, cyano, amide, carbamoyl, carboxylic acid, ester, thioether, alkylthioether, thiol, and ureido groups. Those of skill in the art will recognize that each of these groups may in turn be substituted. Examples of linkers include, but are not limited to, pH-sensitive linkers, protease cleavable peptide linkers, nuclease sensitive nucleic acid linkers, lipase sensitive lipid linkers, glycosidase sensitive carbohydrate linkers, hypoxia sensitive linkers, photo-cleavable linkers, heat-labile linkers, enzyme cleavable linkers (e.g., esterase cleavable linker), ultrasound-sensitive linkers, and x-ray cleavable linkers. 
     The term “pharmaceutically acceptable salt(s)” refers to salts of acidic or basic groups that may be present in compounds used in the present compositions. Compounds included in the present compositions that are basic in nature are capable of forming a variety of salts with various inorganic and organic acids. The acids that may be used to prepare pharmaceutically acceptable acid addition salts of such basic compounds are those that form non-toxic acid addition salts, i.e., salts containing pharmacologically acceptable anions, including but not limited to sulfate, citrate, malate, acetate, oxalate, chloride, bromide, iodide, nitrate, sulfate, bisulfate, phosphate, acid phosphate, isonicotinate, acetate, lactate, salicylate, citrate, tartrate, oleate, tannate, pantothenate, bitartrate, ascorbate, succinate, maleate, gentisinate, fumarate, gluconate, glucaronate, saccharate, formate, benzoate, glutamate, methanesulfonate, ethanesulfonate, benzenesulfonate, p-toluenesulfonate and pamoate (i.e., 1,1′-methylene-bis-(2-hydroxy-3-naphthoate)) salts. Compounds included in the present compositions that include an amino moiety may form pharmaceutically acceptable salts with various amino acids, in addition to the acids mentioned above. Compounds included in the present compositions, that are acidic in nature are capable of forming base salts with various pharmacologically acceptable cations. Examples of such salts include alkali metal or alkaline earth metal salts and, particularly, calcium, magnesium, sodium, lithium, zinc, potassium, and iron salts. 
     If the compounds described herein are obtained as an acid addition salt, the free base can be obtained by basifying a solution of the acid salt. Conversely, if the product is a free base, an addition salt, particularly a pharmaceutically acceptable addition salt, may be produced by dissolving the free base in a suitable organic solvent and treating the solution with an acid, in accordance with conventional procedures for preparing acid addition salts from base compounds. Those skilled in the art will recognize various synthetic methodologies that may be used to prepare non-toxic pharmaceutically acceptable addition salts. 
     A pharmaceutically acceptable salt can be derived from an acid selected from 1-hydroxy-2-naphthoic acid, 2,2-dichloroacetic acid, 2-hydroxyethanesulfonic acid, 2-oxoglutaric acid, 4-acetamidobenzoic acid, 4-aminosalicylic acid, acetic acid, adipic acid, ascorbic acid, aspartic acid, benzenesulfonic acid, benzoic acid, camphoric acid, camphor-10-sulfonic acid, capric acid (decanoic acid), caproic acid (hexanoic acid), caprylic acid (octanoic acid), carbonic acid, cinnamic acid, citric acid, cyclamic acid, dodecylsulfuric acid, ethane-1,2-disulfonic acid, ethanesulfonic acid, formic acid, fumaric acid, galactaric acid, gentisic acid, glucoheptonic acid, gluconic acid, glucuronic acid, glutamic acid, glutaric acid, glycerophosphoric acid, glycolic acid, hippuric acid, hydrobromic acid, hydrochloric acid, isethionic, isobutyric acid, lactic acid, lactobionic acid, lauric acid, maleic acid, malic acid, malonic acid, mandelic acid, methanesulfonic acid, mucic, naphthalene-1,5-disulfonic acid, naphthalene-2-sulfonic acid, nicotinic acid, nitric acid, oleic acid, oxalic acid, palmitic acid, pamoic acid, pantothenic, phosphoric acid, proprionic acid, pyroglutamic acid, salicylic acid, sebacic acid, stearic acid, succinic acid, sulfuric acid, tartaric acid, thiocyanic acid, toluenesulfonic acid, trifluoroacetic, and undecylenic acid. 
     The term “bioavailable” is art-recognized and refers to a form of the subject invention that allows for it, or a portion of the amount administered, to be absorbed by, incorporated to, or otherwise physiologically available to a subject or patient to whom it is administered. 
     It will be appreciated that the following examples are intended to illustrate but not to limit the present invention. Various other examples and modifications of the foregoing description and examples will be apparent to a person skilled in the art after reading the disclosure without departing from the spirit and scope of the invention, and it is intended that all such examples or modifications be included within the scope of the appended claims. All publications and patents referenced herein are hereby incorporated by reference in their entirety. 
     EXAMPLES 
     Example 1: Synthesis, HPLC Analysis and Membrane Permeation of the Conjugates 
     Synthesis and HPLC analysis of the compounds described herein were carried out with methods disclosed in the Examples A, 1-7, and 14 of PCT Application No. PCT/US15/38569 (WO2016/004048) filed Jun. 30, 2015, the contents of which are incorporated herein by reference. 
     Example 2: Phase 1 Studies Using Conjugate 57 
     The objectives of Phase 1 were to assess the safety and tolerability and determine the maximum tolerated dose and recommended Phase 2 dose of Conjugate 57 when administered intravenously on an every 3 week schedule in patients with somatostatin receptor 2 expressing advanced cancers (including gastroenteropancreatic or lung or thymus or other neuroendocrine tumors or small cell lung cancer or large cell neuroendocrine carcinoma of the lung). It also characterized both acute and chronic toxicities of Conjugate 57, characterized key pharmacokinetic parameters of Conjugate 57, DM1, and peptide ligand from Conjugate 57, assessed the potential of Conjugate 57 to induce anti-drug antibodies, and assessed preliminary anti-tumor activity by using standard tumor response criteria (RECIST 1.1) and pharmacodynamic (PDc) biomarker changes that include chromogranin A (CgA), neuron-specific enolase (NSE), and circulating tumor cells (CTCs) in the blood, and 5-hydroxyindoleacetic acid (5-HIAA) in the urine. In addition, the study explored the relationships between tumor SSTR2 expression as measured by multiple modalities (somatostatin analog radioimaging, immunohistochemistry, CTCs, or exosome analyses) and PK, efficacy, safety, anti-Conjugate 57 antibodies, and PDc biomarker changes in the blood. Phase 1 study had two parts: Phase 1 Part A (dose escalation) and Phase 1 Part B (early expansion). 
     Both male and female pateients were enrolled. The ages of the pateients ranged from 27 to 74 with a median age of 61. The tumors of the patients included gastrointestinal neuroendocrine tumor (GI NET), pancreatic neuroendocrine tumor (PNET), lung neuroendocrine tumor (lung NET), lung larget cell neuroendocrine carcinoma, Pheochromocytoma (Pheo), neuroendocrine tumor (NET) of unknown primary, and small cell lung cancer (SCLC). 
     All patients were required to have SSTR2 expressing tumors. Tumor SSTR2 expression was determined by imaging within the preceding approximately 6 months, with Octreoscan or  68 Ga-DOTATATE,  68 Ga-DOTATOC, or  68 Ga-DOTANOC. 
     The acetate salt of Conjugate 57 was administered to a patient as a 1 hour IV infusion once on an every 3 week schedule to escalating cohorts of 2-6 patients. Patients received Conjugate 57 treatment for 3 weeks, 6 weeks, 9 weeks, 12 weeks, 15 weeks, 18 weeks, 21 weeks, 24 weeks, 27 weeks, 30 weeks, 33 weeks, 36 weeks, 39 weeks, 42 weeks, 45 weeks, 48 weeks, 51 weeks, 54 weeks, 57 weeks, or 60 weeks. There were 7 Cohorts with the starting does of 1.0 mg and the highest dose of 25.0 mg. The doses of Conjugate 57 given to pateints were flat: 1.0 mg, 2.0 mg, 4.0 mg, 8.0 mg, 12.0 mg, 18.0 mg and 25.0 mg. Conjugate 57 concentrate for Solution for Injection is a sterile concentrated liquid containing Conjugate 57, mannitol, Polyoxyl 15 Hydroxystearate and acetate buffer. Each dosage unit contains 2.5 mg of Conjugate 57 (free-form) per mL, 50 mg/mL mannitol, 20 mg/mL Polyoxyl 15 Hydroxystearate and pH 4.0-4.8 acetate buffer in a stoppered 10 mL clear vial. Prior to administration, the product was diluted with 5% Mannitol Injection USP. The resulting diluted Conjugate 57 formulation can be infused intravenously. 
     Serial PK samples were collected prior, during and up to 10 hours after the start of infusion on Day 1 of Cycle 1 and Cycle 3. Samples were analyzed for Conjugate 57, Unconjugated DM1, Unconjugated SSTR2 targeting peptide and free sulfhydryl DM1 (DM1-SH). 
     Disease response was assessed by duration of response and RECIST 1.1. An adaptive Bayesian Logistic Regression Model (BLRM) guided by the Escalation with Overdose Control (EWOC) principle (Babb et al; Neuenschwander et al) was employed to make dose recommendations and estimate the MTD, defined as the dose with the highest posterior probability of targeted toxicity (16%-33%) that fulfills the EWOC (probability &gt;25% of excessive toxicity, i.e. greater than 33%). Intra-patient dose escalation was permitted 
     Plasma pharmacokinetics of Conjugate 57 during dose escalation were calculated as shown in Table 1. Cmax is the maximum (or peak) serum concentration of a drug after the drug has been administrated and before the administration of a second dose. Area under curve to infinity (AUCinf) is a is a theoretical measure of the total exposure of drug to the body from administration till all the drug is eliminated. Clearance (CL) is the volume of plasma cleared of drug per unit time. It is an index of how well a drug is removed irreversibly from circulation. Volume of distribution (Vz) was also measured. Vz represents the degree to which a drug is distributed in body tissue rather than the plasma. 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 Mean Conjugate 57 Plasma Pharmacokinetics 
               
            
           
           
               
               
               
               
               
            
               
                 Conjugate 57 dose 
                 Cmax 
                 AUCinf 
                 CL 
                 Vz 
               
               
                 (mg) 
                 (nM) 
                 (nM · h) 
                 (L/h) 
                 (L) 
               
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 1 
                 7.47 
                 14.6 
                 38 
                 65 
               
               
                 2 
                 20.5 
                 37.9 
                 35 
                 80 
               
               
                 4 
                 74.3 
                 118 
                 20 
                 60 
               
               
                 8 
                 186 
                 341 
                 15 
                 37 
               
               
                 12 
                 293 
                 584 
                 13 
                 33 
               
               
                 18 
                 381 
                 666 
                 16 
                 36 
               
               
                 25 
                 741 
                 1310 
                 11 
                 50 
               
               
                   
               
            
           
         
       
     
     Plasma pharmacokinetics of Conjugate 57 at 18 mg and key metabolites (5 patients) were shown in  FIG. 1 . Conjugate 57 concentration increased during the infusion with a median time of Cmax ranged from 0.5 to 1.1 hours. Median t½ (half-life) was 1.7 hours across all dose cohorts. Conjugate 57 AUCinf increased with the dose. For the 12 mg and higher dose cohorts the AUCinf was above efficacious exposure threshold seen in pre-clinical xenograft studies of SCLC modles. DM1-SH levels remained low with respect to Conjugate 57. The maximum tolerated dose (MTD) was determined to be 18 mg. 
     A 45-year-old female patient with well differentiated, intermediate grade GI (large bowel) NET with metastasis to lymph nodes, bone, lung, and brain was treated with Conjugate 57 at 18 mg. Her tumors progressed on all prior therapies: lanreotide, mTOR inhibitor, and/or 177Lu-DOTATATE. Her disease related symptoms of flushing disappeared after first dose of Conjugate 57 and have not recurred. Circulating biomarkers of neuroendocrine tumors (NETs), including chromogranin A (CgA), neuron specific enolase (NSE) and circulating tumor cells (CTC), were collected and measured over time. Increased CgA is predictive of poor morphological response, progression free survival (PFS), and overall survival (OS) in pancreatic NETs. Decline in plasma concentration of NSE has been associated with response to treatment. Changes in CTCs has been associated with response to treatment in patients with NETs. As shown in  FIG. 2 , the levels of all three biomarkers decreased over time: CgA in  FIG. 2A , NSE in  FIG. 2B  and CTC in  FIG. 2C . 
     Conjugate 57 was well tolerated with preliminary evidence of antitumor activities. Among 15 NET patients who were evaluable for response, 11 had stable disease (SD) at 9 2065-1080USPRO2 Coversheetweeks, of whom 8 were sustained for 18-45 weeks, including 2 ongoing patients with SD for 44 and 45 weeks. Target lesion shrinkage was observed in 3 patients (dose range 8-18 mg). One SCLC patient had SD for 12 weeks. 
     EQUIVALENTS AND SCOPE 
     Those skilled in the art will recognize or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments in accordance with the invention described herein. The scope of the present invention is not intended to be limited to the above Description, but rather is as set forth in the appended claims. 
     In the claims, articles such as “a,” “an,” and “the” may mean one or more than one unless indicated to the contrary or otherwise evident from the context. Claims or descriptions that include “or” between one or more members of a group are considered satisfied if one, more than one, or all of the group members are present in, employed in, or otherwise relevant to a given product or process unless indicated to the contrary or otherwise evident from the context. The invention includes embodiments in which exactly one member of the group is present in, employed in, or otherwise relevant to a given product or process. The invention includes embodiments in which more than one, or the entire group members are present in, employed in, or otherwise relevant to a given product or process. 
     It is also noted that the term “comprising” is intended to be open and permits but does not require the inclusion of additional elements or steps. When the term “comprising” is used herein, the term “consisting of” is thus also encompassed and disclosed. 
     Where ranges are given, endpoints are included. Furthermore, it is to be understood that unless otherwise indicated or otherwise evident from the context and understanding of one of ordinary skill in the art, values that are expressed as ranges can assume any specific value or subrange within the stated ranges in different embodiments of the invention, to the tenth of the unit of the lower limit of the range, unless the context clearly dictates otherwise. 
     In addition, it is to be understood that any particular embodiment of the present invention that falls within the prior art may be explicitly excluded from any one or more of the claims. Since such embodiments are deemed to be known to one of ordinary skill in the art, they may be excluded even if the exclusion is not set forth explicitly herein. Any particular embodiment of the compositions of the invention (e.g., any antibiotic, therapeutic or active ingredient; any method of production; any method of use; etc.) can be excluded from any one or more claims, for any reason, whether or not related to the existence of prior art. 
     It is to be understood that the words which have been used are words of description rather than limitation, and that changes may be made within the purview of the appended claims without departing from the true scope and spirit of the invention in its broader aspects. 
     While the present invention has been described at some length and with some particularity with respect to the several described embodiments, it is not intended that it should be limited to any such particulars or embodiments or any particular embodiment, but it is to be construed with references to the appended claims so as to provide the broadest possible interpretation of such claims in view of the prior art and, therefore, to effectively encompass the intended scope of the invention.