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Title: Administering
bifunctional molecules containing a drug moiety and presenter protein
ligand for therapy
United States Patent: 7,390,784
Issued: June 24, 2008
Inventors: Briesewitz;
Roger (Mountain View, CA), Crabtree; Gerald R. (Woodside, CA), Wandless;
Thomas (Menlo Park, CA), Ray; Gregory Thomas (Stanford, CA), Vogel; Kurt
W. (Palo Alto, CA)
Assignee: The Board of
Trustees of the Leland Stanford Junior University (Palo Alto, CA)
Appl. No.: 11/011,499
Filed: December 13, 2004
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George Washington University's Healthcare MBA
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Abstract
Bifunctional molecules and methods for
their use in the production of binary complexes in a host are provided.
The bifunctional molecule is a conjugate of a drug moiety and a presenter
protein ligand. In the subject methods, an effective amount of the
bifunctional molecule is administered to the host. The bifunctional
molecule binds to the presenter protein to produce a binary complex that
exhibits at least one of improved affinity, specificity or selectivity as
compared to the corresponding free drug. The subject methods and
compositions find use in a variety of therapeutic applications.
Description of the
Invention
SUMMARY OF THE INVENTION
Bifunctional molecules capable of producing at least a binary complex with a
host endogenous presenter protein are provided. In the subject methods, a
bifunctional molecule is synthesized by covalently linking an endogenous
presenter protein ligand to a drug moiety, either directly or through a
linking group. An effective amount of a bifunctional molecule is
administered to the host, where the bifunctional molecule binds to the
endogenous presenter protein to produce the binary complex. The resultant
binary complex modulates (e.g. enlarges) the target binding surface area of
the drug moiety, i.e. the surface area available for binding with the
target, in a manner such that at least one of enhanced affinity, specificity
or selectivity are observed as compared to that observed with the free drug.
In one embodiment where the binary complex results in enhanced affinity, a
tripartite complex is produced in which binding interactions are present
between the presenter and target as well as the drug moiety and target. In a
second embodiment where the binary complex results in enhanced specificity,
delivery of the drug as a bifunctional molecule results in differential
affinity with respect to its potential targets such that the drug moiety
binds more to its desirable target than to its undesirable targets as
compared to a free drug control situation, e.g. where tripartite complexes
produced between the binary complex and undesired targets are characterized
by the presence of unfavorable interactions while tripartite complexes
produced between the binary complex and the desired target are characterized
by the presence of no interactions, neutral interactions or favorable
interactions. In a third embodiment where the binary complex results in
enhanced selectivity, tripartite complexes produced with undesired targets
in a first cell or tissue type are characterized by the presence of
unfavorable interactions while the bifunctional molecule affects the desired
target in a second cell or tissue type, e.g. a second type of cell or tissue
in the same organism or a microorganism in a host organism, without
formation of a binary complex between the bifunctional molecule and a
presenter protein due to the lack of the presenter protein.
The subject methods and compositions find use in a variety of therapeutic
applications.
DESCRIPTION OF THE SPECIFIC EMBODIMENTS
Bifunctional molecules, synthesis and screening methods, and methods for
their use in the production of at least binary complexes in a host are
provided. The bifunctional molecules have a drug moiety covalently linked to
a presenter protein ligand, either directly or through a linking group. In
the subject methods, an effective amount of the bifunctional molecule is
administered to the host. Upon administration, the bifunctional molecule
binds to the presenter protein to produce the binary complex. The binary
complex has an enlarged target binding surface area as compared to the free
drug such that at least one of enhanced affinity, specificity or selectivity
are observed as compared to the free drug. In a first embodiment in which
increased affinity is observed, the binary complex binds to the target to
form a tripartite complex characterized by the presence of presenter-target
binding interactions as well as drug-target binding interactions. The
subject methods and compositions find use in a variety of therapeutic
applications. In further describing the subject invention, the bifunctional
molecules and methods for their production will be described first, followed
by a discussion of applications in which the bifunctional molecules find
use.
Before the subject invention is described further, it is to be understood
that the invention is not limited to the particular embodiments of the
invention described below, as variations of the particular embodiments may
be made and still fall within the scope of the appended claims. It is also
to be understood that the terminology employed is for the purpose of
describing particular embodiments, and is not intended to be limiting.
Instead, the scope of the present invention will be established by the
appended claims.
In this specification and the appended claims, the singular forms "a," "an,"
and "the" include plural reference unless the context clearly dictates
otherwise. Unless defined otherwise, all technical and scientific terms used
herein have the same meaning as commonly understood to one of ordinary skill
in the art to which this invention belongs.
Though not wishing to be bound by any particular theory, the subject
invention provides a means for improving at least one of the affinity or
specificity or selectivity of a small molecule drug for its desired target
by enlarging the target binding surface area of the drug moiety as compared
to the free drug. Enhanced affinity, specificity or selectivity of the drug
is accomplished by presenting it to its drug target as a binary complex made
up of a bifunctional molecule of the drug and presenter protein ligand bound
to a presenter protein. Interactions between the presenter protein and the
drug target, such as favorable interactions, neutral interactions or
repulsive interactions, in combination with interactions between the drug
moiety and its target, result in a modulation of the overall binding profile
of the drug moiety for its various targets, as compared to a free drug
control. As such, by administering a small molecule drug as a bifunctional
molecule according to the subject invention, one can achieve improved
results as compared to the results obtainable by administration of the small
molecule drug by itself.
Bifunctional Molecule
A critical element of the subject invention is the bifunctional molecule.
The bifunctional molecule is a non-naturally occurring or synthetic
compound. The bifunctional molecule is further characterized in that the
presenter protein ligand and the drug moiety are different, such that the
bifuntional molecule may be viewed as a heterodimeric compound produced by
the joining of two different moieties. In many embodiments, the presenter
protein ligand and the drug moiety are chosen such that the corresponding
drug target and presenter protein do not naturally associate with each other
to produce a biological effect. In many preferred embodiments, the
bifunctional molecules are capable of simultaneously binding two distinct
compounds, i.e. a target and a presenter protein, to form a tripartite
complex. The bifunctional molecule has a drug moiety bonded to a ligand for
a presenter protein, either directly or through a linking group. The
molecular weight of the bifunctional molecule is generally at least about
100 D, usually at least about 400 D and more usually at least about 500 D,
and may be as great as 2000 D or greater, but usually does not exceed about
5000 D.
The bifunctional molecule is further characterized in that the drug moiety
has improved activity as compared to free drug. By improved activity is
meant that the drug moiety has a more desirable effect with respect to the
condition being treated, as compared to the corresponding free drug from
which the drug moiety of the bifunctional molecule is derived. In many
embodiments, the bifunctional molecule is characterized by having improved
affinity for its target as compared to its corresponding drug, i.e. a
control. The magnitude of enhanced affinity and/or specificity will be at
least about 2 fold, usually at least about 5 fold and in many embodiments at
least 10 fold. In many embodiments, the affinity of the bifunctional
molecule for its target will be at least about 10.sup.-4 M, usually at least
about 10.sup.-6 M. Additionally and/or alternatively, the bifunctional
molecule exhibits improved specificity for its target as compared to a free
drug control. Additionally and/or alternatively, the bifunctional molecule
exhibits improved selectively for its target as compared to a free drug
control.
Bifunctional molecules are generally described by the formula: Z-L-X wherein
X is a drug moiety; L is bond or linking group; and Z is a ligand for an
endogenous presenter protein; with the proviso that X and Z are different.
Drug Moiety: X
The drug moiety X may be any molecule, as well as binding portion or
fragment thereof, that is capable of modulating a biological process in a
living host, either by itself or in the context of the presenter protein/bifunctional
molecule binary complex. Generally, X is a small organic molecule that is
capable of binding to the target of interest. As the drug moiety of the
bifunctional molecule is a small molecule, it generally has a molecular
weight of at least about 50 D, usually at least about 100 D, where the
molecular weight may be as high as 500 D or higher, but will usually not
exceed about 2000 D.
The drug moiety is capable of interacting with a target in the host into
which the bifunctional molecule is administered during practice of the
subject methods. The target may be a number of different types of naturally
occurring structures, where targets of interest include both intracellular
and extracellular targets, where such targets may be proteins,
phospholipids, nucleic acids and the like, where proteins are of particular
interest. Specific proteinaceous targets of interest include, without
limitation, enzymes, e.g. kinases, phosphatases, reductases, cyclooxygenases,
proteases and the like, targets comprising domains involved in
protein-protein interactions, such as the SH2, SH3, PTB and PDZ domains,
structural proteins, e.g. actin, tubulin, etc., membrane receptors,
immunoglobulins, e.g. IgE, cell adhesion receptors, such as integrins, etc,
ion channels, transmembrane pumps, transcription factors, signaling
proteins, and the like.
The drug moiety of the bifunctional compound will include one or more
functional groups necessary for structural interaction with the target, e.g.
groups necessary for hydrophobic, hydrophilic, electrostatic or even
covalent interactions, depending on the particular drug and its intended
target. Where the target is a protein, the drug moiety will include
functional groups necessary for structural interaction with proteins, such
as hydrogen bonding, hydrophobic-hydrophobic interactions, electrostatic
interactions, etc., and will typically include at least an amine, amide,
sulfhydryl, carbonyl, hydroxyl or carboxyl group, preferably at least two of
the functional chemical groups. As described in greater detail below, the
drug moiety will also comprise a region that may be modified and/or
participate in covalent linkage to the other components of the bifunctional
molecule, such as the presenter protein ligand or linker, without
substantially adversely affecting the moiety's ability to bind to its
target.
The drug moieties often comprise cyclical carbon or heterocyclic structures
and/or aromatic or polyaromatic structures substituted with one or more of
the above functional groups. Also of interest as drug moieties are
structures found among biomolecules, including peptides, saccharides, fatty
acids, steroids, purines, pyrimidines, derivatives, structural analogs or
combinations thereof. Such compounds may be screened to identify those of
interest, where a variety of different screening protocols are known in the
art.
The drug moiety of the bifunctional molecule may be derived from a naturally
occurring or synthetic compound that may be obtained from a wide variety of
sources, including libraries of synthetic or natural compounds. For example,
numerous means are available for random and directed synthesis of a wide
variety of organic compounds and biomolecules, including the preparation of
randomized oligonucleotides and oligopeptides. Alternatively, libraries of
natural compounds in the form of bacterial, fungal, plant and animal
extracts are available or readily produced. Additionally, natural or
synthetically produced libraries and compounds are readily modified through
conventional chemical, physical and biochemical means, and may be used to
produce combinatorial libraries. Known pharmacological agents may be
subjected to directed or random chemical modifications, such as acylation,
alkylation, esterification, amidification, etc. to produce structural
analogs.
As such, the drug moiety may be obtained from a library of naturally
occurring or synthetic molecules, including a library of compounds produced
through combinatorial means, i.e. a compound diversity combinatorial
library. When obtained from such libraries, the drug moiety employed will
have demonstrated some desirable activity in an appropriate screening assay
for the activity. Combinatorial libraries, as well as methods for the
production and screening, are known in the art and described in: U.S. Pat.
Nos. 5,741,713; 5,734,018; 5,731,423; 5,721,099; 5,708,153; 5,698,673;
5,688,997; 5,688,696; 5,684,711; 5,641,862; 5,639,603; 5,593,853; 5,574,656;
5,571,698; 5,565,324; 5,549,974; 5,545,568; 5,541,061; 5,525,735; 5,463,564;
5,440,016; 5,438,119; 5,223,409, the disclosures of which are herein
incorporated by reference.
Specific drugs of interest from which the drug moiety may be derived
include, but are not limited to: psychopharmacological agents, such as (1)
central nervous system depressants, e.g. general anesthetics (barbiturates,
benzodiazepines, steroids, cyclohexanone derivatives, and miscellaneous
agents), sedative-hypnotics (benzodiazepines, barbiturates, piperidinediones
and triones, quinazoline derivatives, carbamates, aldehydes and derivatives,
amides, acyclic ureides, benzazepines and related drugs, phenothiazines,
etc.), central voluntary muscle tone modifying drugs (anticonvulsants, such
as hydantoins, barbiturates, oxazolidinediones, succinimides, acylureides,
glutarimides, benzodiazepines, secondary and tertiary alcohols,
dibenzazepine derivatives, valproic acid and derivatives, GABA analogs,
etc.), analgesics (morphine and derivatives, oripavine derivatives,
morphinan derivatives, phenylpiperidines, 2,6-methane-3-benzazocaine
derivatives, diphenylpropylamines and isosteres, salicylates, p-aminophenol
derivatives, 5-pyrazolone derivatives, arylacetic acid derivatives,
fenamates and isosteres, etc.) and antiemetics (anticholinergics,
antihistamines, antidopaminergics, etc.), (2) central nervous system
stimulants, e.g. analeptics (respiratory stimulants, convulsant stimulants,
psychomotor stimulants), narcotic antagonists (morphine derivatives,
oripavine derivatives, 2,6-methane-3-benzoxacine derivatives, morphinan
derivatives) nootropics, (3) psychophammacologicals, e.g. anxiolytic
sedatives (benzodiazepines, propanediol carbamates) antipsychotics (phenothiazine
derivatives, thioxanthine derivatives, other tricyclic compounds,
butyrophenone derivatives and isosteres, diphenylbutylamine derivatives,
substituted benzamides, arylpiperazine derivatives, indole derivatives,
etc.), antidepressants (tricyclic compounds, MAO inhibitors, etc.), (4)
respiratory tract drugs, e.g. central antitussives (opium alkaloids and
their derivatives); pharmacodynamic agents, such as (1) peripheral nervous
system drugs, e.g. local anesthetics (ester derivatives, amide derivatives),
(2) drugs acting at synaptic or neuroeffector junctional sites, e.g.
cholinergic agents, cholinergic blocking agents, neuromuscular blocking
agents, adrenergic agents, antiadrenergic agents, (3) smooth muscle active
drugs, e.g. spasmolytics (anticholinergics, musculotropic spasmolytics),
vasodilators, smooth muscle stimulants, (4) histamines and antihistamines,
e.g. histamine and derivative thereof (betazole), antihistamines
(H.sub.1-antagonists, H.sub.2-antagonists), histamine metabolism drugs, (5)
cardiovascular drugs, e.g. cardiotonics (plant extracts, butenolides,
pentadienolids, alkaloids from erythrophleum species, ionophores, -adrenoceptor
stimulants, etc), antiarrhythmic drugs, antihypertensive agents,
antilipidemic agents (clofibric acid derivatives, nicotinic acid
derivatives, hormones and analogs, antibiotics, salicylic acid and
derivatives), antivaricose drugs, hemostyptics, (6) blood and hemopoietic
system drugs, e.g. antianemia drugs, blood coagulation drugs (hemostatics,
anticoagulants, antithrombotics, thrombolytics, blood proteins and their
fractions), (7) gastrointestinal tract drugs, e.g. digestants (stomachics,
choleretics), antiulcer drugs, antidiarrheal agents, (8) locally acting
drugs;
chemotherapeutic agents, such as (1) anti-infective agents, e.g.
ectoparasiticides (chlorinated hydrocarbons, pyrethins, sulfurated
compounds), anthelmintics, antiprotozoal agents, antimalarial agents,
antiamebic agents, antileiscmanial drugs, antitrichomonal agents,
antitrypanosomal agents, sulfonamides, antimycobacterial drugs, antiviral
chemotherapeutics, etc., and (2) cytostatics, i.e. antineoplastic agents or
cytotoxic drugs, such as alkylating agents, e.g. Mechlorethamine
hydrochloride (Nitrogen Mustard, Mustargen, HN2), Cyclophosphamide (Cytovan,
Endoxana), Ifosfamide (IFEX), Chlorambucil (Leukeran), Melphalan
(Phenylalanine Mustard, L-sarcolysin, Alkeran, L-PAM), Busulfan (Myleran),
Thiotepa (Triethylenethiophosphoramide), Carmustine (BiCNU, BCNu, Lomustine
(CeeNU, CCNU), Streptozocin (Zanosar) and the like; plant alkaloids, e.g.
Vincristine (Oncovin), Vinblastine (Velban, Velbe), Paclitaxel (Taxol), and
the like; antimetabolites, e.g. Methotrexate (MTX), Mercaptopurine (Purinethol,
6-MP), Thioguanine (6-TG), Fluorouracil (5-FU), Cytarabine (Cytosar-U, Ara-C),
Azacitidine (Mylosar, 5-AZA) and the like; antibiotics, e.g. Dactinomycin (Actinomycin
D, Cosmegen), Doxorubicin (Adriamycin), Daunorubicin (duanomycin, Cerubidine),
Idarubicin (Idamycin), Bleomycin (Blenoxane), Picamycin (Mithramycin,
Mithracin), Mitomycin (Mutamycin) and the like, and other anticellular
proliferative agents, e.g. Hydroxyurea (Hydrea), Procarbazine (Mutalane),
Dacarbazine (DTIC-Dome), Cisplatin (Platinol) Carboplatin (Paraplatin),
Asparaginase (Elspar) Etoposide (VePesid, VP-16-213), Amsarcrine (AMSA, m-AMSA),
Mitotane (Lysodren), Mitoxantrone (Novatrone), and the like;
Antibiotics, such as: aminoglycosides, e.g. amikacin, apramycin, arbekacin,
bambermycins, butirosin, dibekacin, dihydrostreptomycin, fortimicin,
gentamicin, isepamicin, kanamycin, micronomcin, neomycin, netilmicin,
paromycin, ribostamycin, sisomicin, spectinomycin, streptomycin, tobramycin,
trospectomycin; amphenicols, e.g. azidamfenicol, chloramphenicol,
florfenicol, and theimaphenicol; ansamycins, e.g. rifamide, rifampin,
rifamycin, rifapentine, rifaximin; .beta.-lactams, e.g. carbacephems,
carbapenems, cephalosporins, cehpamycins, monobactams, oxaphems, penicillins;
lincosamides, e.g. clinamycin, lincomycin; macrolides, e.g. clarithromycin,
dirthromycin, erythromycin, etc.; polypeptides, e.g. amphomycin, bacitracin,
capreomycin, etc.; tetracyclines, e.g. apicycline, chlortetracycline,
clomocycline, etc.; synthetic antibacterial agents, such as
2,4-diaminopyrimidines, nitrofurans, quinolones and analogs thereof,
sulfonamides, sulfones;
Antifungal agents, such as: polyenes, e.g. amphotericin B, candicidin,
dermostatin, filipin, fungichromin, hachimycin, hamycin, lucensomycin,
mepartricin, natamycin, nystatin, pecilocin, perimycin; synthetic
antifungals, such as allylamines, e.g. butenafine, naftifine, terbinafine;
imidazoles, e.g. bifonazole, butoconazole, chlordantoin, chlormidazole,
etc., thiocarbamates, e.g. tolciclate, triazoles, e.g. fluconazole,
itraconazole, terconazole;
Anthelmintics, such as: arecoline, aspidin, aspidinol, dichlorophene,
embelin, kosin, napthalene, niclosamide, pelletierine, quinacrine,
alantolactone, amocarzine, amoscanate, ascaridole, bephenium, bitoscanate,
carbon tetrachloride, carvacrol, cyclobendazole, diethylcarbamazine, etc.;
Antimalarials, such as: acedapsone, amodiaquin, arteether, artemether,
artemisinin, artesunate, atovaquone, bebeerine, berberine, chirata,
chlorguanide, chloroquine, chlorprogaunil, cinchona, cinchonidine,
cinchonine, cycloguanil, gentiopicrin, halofantrine, hydroxychloroquine,
mefloquine hydrochloride, 3-methylarsacetin, pamaquine, plasmocid,
primaquine, pyrimethamine, quinacrine, quinidine, quinine, quinocide,
quinoline, dibasic sodium arsenate;
Antiprotozoan agents, such as: acranil, tinidazole, ipronidazole,
ethylstibamine, pentamidine, acetarsone, aminitrozole, anisomycin, nifuratel,
tinidazole, benzidazole, suramin, and the like.
Name brand drugs of interest include, but are not limited to: Rezulin.TM.,
Lovastatin.TM., Enalapril.TM., Prozac.TM., Prilosec.TM., Lipotor.TM.,
Claritin.TM., Zocor.TM., Ciprofloxacin.TM., Viagra.TM., Crixivan.TM.,
Ritalin.TM., and the like.
Drug compounds of interest from which drug moieties may be derived are also
listed in: Goodman & Gilman's, The Pharmacological Basis of Therapeutics
(9th Ed) (Goodman et al. eds) (McGraw-Hill) (1996); and 1999 Physician's
Desk Reference (1998).
Specific compounds of interest also include, but are not limited to:
antineoplastic agents, as disclosed in U.S. Pat. Nos. 5,880,161, 5,877,206,
5,786,344, 5,760,041, 5,753,668, 5,698,529, 5,684,004, 5,665,715, 5,654,484,
5,624,924, 5,618,813, 5,610,292, 5,597,831, 5,530,026, 5,525,633, 5,525,606,
5,512,678, 5,508,277, 5,463,181, 5,409,893, 5,358,952, 5,318,965, 5,223,503,
5,214,068, 5,196,424, 5,109,024, 5,106,996, 5,101,072, 5,077,404, 5,071,848,
5,066,493, 5,019,390, 4,996,229, 4,996,206, 4,970,318, 4,968,800, 4,962,114,
4,927,828, 4,892,887, 4,889,859, 4,886,790, 4,882,334, 4,882,333, 4,871,746,
4,863,955, 4,849,563, 4,845,216, 4,833,145, 4,824,955, 4,785,085, 476,925,
4,684,747, 4,618,685, 4,611,066, 4,550,187, 4,550,186, 4,544,501, 4,541,956,
4,532,327, 4,490,540, 4,399,283, 4,391,982, 4,383,994, 4,294,763, 4,283,394,
4,246,411, 4,214,089, 4,150,231, 4,147,798, 4,056,673, 4,029,661, 4,012,448;
psycopharmacological/psychotropic agents, as disclosed in U.S. Pat. Nos.
5,192,799, 5,036,070, 4,778,800, 4,753,951, 4,590,180, 4,690,930, 4,645,773,
4,427,694, 4,424,202, 4,440,781, 5,686,482, 5,478,828, 5,461,062, 5,387,593,
5,387,586, 5,256,664, 5,192,799, 5,120,733, 5,036,070, 4,977,167, 4,904,663,
4,788,188, 4,778,800, 4,753,951, 4,690,930, 4,645,773, 4,631,285, 4,617,314,
4,613,600, 4,590,180, 4,560,684, 4,548,938, 4,529,727, 4,459,306, 4,443,451,
4,440,781, 4,427,694, 4,424,202, 4,397,853, 4,358,451, 4,324,787, 4,314,081,
4,313,896, 4,294,828, 4,277,476, 4,267,328, 4,264,499, 4,231,930, 4,194,009,
4,188,388, 4,148,796, 4,128,717, 4,062,858, 4,031,226, 4,020,072, 4,018,895,
4,018,779, 4,013,672, 3,994,898, 3,968,125, 3,939,152, 3,928,356, 3,880,834,
3,668,210;
cardiovascular agents, as disclosed in U.S. Pat. Nos. 4,966,967, 5,661,129,
5,552,411, 5,332,737, 5,389,675, 5,198,449, 5,079,247, 4,966,967, 4,874,760,
4,954,526, 5,051,423, 4,888,335, 4,853,391, 4,906,634, 4,775,757, 4,727,072,
4,542,160, 4,522,949, 4,524,151, 4,525,479, 4,474,804, 4,520,026, 4,520,026,
5,869,478, 5,859,239, 5,837,702, 5,807,889, 5,731,322, 5,726,171, 5,723,457,
5,705,523, 5,696,111, 5,691,332, 5,679,672, 5,661,129, 5,654,294, 5,646,276,
5,637,586, 5,631,251, 5,612,370, 5,612,323, 5,574,037, 5,563,170, 5,552,411,
5,552,397, 5,547,966, 5,482,925, 5,457,118, 5,414,017, 5,414,013, 5,401,758,
5,393,771, 5,362,902, 5,332,737, 5,310,731, 5,260,444, 5,223,516, 5,217,958,
5,208,245, 5,202,330, 5,198,449, 5,189,036, 5,185,362, 5,140,031, 5,128,349,
5,116,861, 5,079,247, 5,070,099, 5,061,813, 5,055,466, 5,051,423, 5,036,065,
5,026,712, 5,011,931, 5,006,542, 4,981,843, 4,977,144, 4,971,984, 4,966,967,
4,959,383, 4,954,526, 4,952,692, 4,939,137, 4,906,634, 4,889,866, 4,888,335,
4,883,872, 4,883,811, 4,847,379, 4,835,157, 4,824,831, 4,780,538, 4,775,757,
4,774,239, 4,771,047, 4,769,371, 4,767,756, 4,762,837, 4,753,946, 4,752,616,
4,749,715, 4,738,978, 4,735,962, 4,734,426, 4,734,425, 4,734,424, 4,730,052,
4,727,072, 4,721,796, 4,707,550, 4,704,382, 4,703,120, 4,681,970, 4,681,882,
4,670,560, 4,670,453, 4,668,787, 4,663,337, 4,663,336, 4,661,506, 4,656,267,
4,656,185, 4,654,357, 4,654,356, 4,654,355, 4,654,335, 4,652,578, 4,652,576,
4,650,874, 4,650,797, 4,649,139, 4,647,585, 4,647,573, 4,647,565, 4,647,561,
4,645,836, 4,639,461, 4,638,012, 4,638,011, 4,632,931, 4,631,283, 4,628,095,
4,626,548, 4,614,825, 4,611,007, 4,611,006, 4,611,005, 4,609,671, 4,608,386,
4,607,049, 4,607,048, 4,595,692, 4,593,042, 4,593,029, 4,591,603, 4,588,743,
4,588,742, 4,588,741, 4,582,854, 4,575,512, 4,568,762, 4,560,698, 4,556,739,
4,556,675, 4,555,571, 4,555,570, 4,555,523, 4,550,120, 4,542,160, 4,542,157,
4,542,156, 4,542,155, 4,542,151, 4,537,981, 4,537,904, 4,536,514, 4,536,513,
4,533,673, 4,526,901, 4,526,900, 4,525,479, 4,524,151, 4,522,949, 4,521,539,
4,520,026, 4,517,188, 4,482,562, 4,474,804, 4,474,803, 4,472,411, 4,466,979,
4,463,015, 4,456,617, 4,456,616, 4,456,615, 4,418,076, 4,416,896, 4,252,815,
4,220,594, 4,190,587, 4,177,280, 4,164,586, 4,151,297, 4,145,443, 4,143,054,
4,123,550, 4,083,968, 4,076,834, 4,064,259, 4,064,258, 4,064,257, 4,058,620,
4,001,421, 3,993,639, 3,991,057, 3,982,010, 3,980,652, 3,968,117, 3,959,296,
3,951,950, 3,933,834, 3,925,369, 3,923,818, 3,898,210, 3,897,442, 3,897,441,
3,886,157, 3,883,540, 3,873,715, 3,867,383, 3,873,715, 3,867,383, 3,691,216,
3,624,126;
antimicrobial agents as disclosed in U.S. Pat. Nos. 5,902,594, 5,874,476,
5,874,436, 5,859,027, 5,856,320, 5,854,242, 5,811,091, 5,786,350, 5,783,177,
5,773,469, 5,762,919, 5,753,715, 5,741,526, 5,709,870, 5,707,990, 5,696,117,
5,684,042, 5,683,709, 5,656,591, 5,643,971, 5,643,950, 5,610,196, 5,608,056,
5,604,262, 5,595,742, 5,576,341, 5,554,373, 5,541,233, 5,534,546, 5,534,508,
5,514,715, 5,508,417, 5,464,832, 5,428,073, 5,428,016, 5,424,396, 5,399,553,
5,391,544, 5,385,902, 5,359,066, 5,356,803, 5,354,862, 5,346,913, 5,302,592,
5,288,693, 5,266,567, 5,254,685, 5,252,745, 5,209,930, 5,196,441, 5,190,961,
5,175,160, 5,157,051, 5,096,700, 5,093,342, 5,089,251, 5,073,570, 5,061,702,
5,037,809, 5,036,077, 5,010,109, 4,970,226, 4,916,156, 4,888,434, 4,870,093,
4,855,318, 4,784,991, 4,746,504, 4,686,221, 4,599,228, 4,552,882, 4,492,700,
4,489,098, 4,489,085, 4,487,776, 4,479,953, 4,477,448, 4,474,807, 4,470,994,
4,370,484, 4,337,199, 4,311,709, 4,308,283, 4,304,910, 4,260,634, 4,233,311,
4,215,131, 4,166,122, 4,141,981, 4,130,664, 4,089,977, 4,089,900, 4,069,341,
4,055,655, 4,049,665, 4,044,139, 4,002,775, 3,991,201, 3,966,968, 3,954,868,
3,936,393, 3,917,476, 3,915,889, 3,867,548, 3,865,748, 3,867,548, 3,865,748,
3,783,160, 3,764,676, 3,764,677;
anti-inflammatory agents as disclosed in U.S. Pat. Nos. 5,872,109,
5,837,735, 5,827,837, 5,821,250, 5,814,648, 5,780,026, 5,776,946, 5,760,002,
5,750,543, 5,741,798, 5,739,279, 5,733,939, 5,723,481, 5,716,967, 5,688,949,
5,686,488, 5,686,471, 5,686,434, 5,684,204, 5,684,041, 5,684,031, 5,684,002,
5,677,318, 5,674,891, 5,672,620, 5,665,752, 5,656,661, 5,635,516, 5,631,283,
5,622,948, 5,618,835, 5,607,959, 5,593,980, 5,593,960, 5,580,888, 5,552,424,
5,552,422 5,516,764, 5,510,361, 5,508,026, 5,500,417, 5,498,405, 5,494,927:
5,476,876 5,472,973 5,470,885, 5,470,842, 5,464,856, 5,464,849 5,462,952,
5,459,151, 5,451,686, 5,444,043 5,436,265, 5,432,181, RE034918, 5,393,756,
5,380,738, 5,376,670, 5,360,811, 5,354,768, 5,348,957, 5,347,029, 5,340,815,
5,338,753, 5,324,648, 5,319,099, 5,318,971, 5,312,821, 5,302,597, 5,298,633,
5,298,522, 5,298,498, 5,290,800, 5,290,788, 5,284,949, 5,280,045, 5,270,319,
5,266,562, 5,256,680, 5,250,700, 5,250,552, 5,248,682, 5,244,917, 5,240,929,
5,234,939, 5,234,937, 5,232,939, 5,225,571, 5,225,418, 5,220,025, 5,212,189,
5,212,172, 5,208,250, 5,204,365, 5,202,350, 5,196,431, 5,191,084, 5,187,175,
5,185,326, 5,183,906, 5,177,079, 5,171,864, 5,169,963, 5,155,122, 5,143,929,
5,143,928, 5,143,927, 5,124,455, 5,124,347, 5,114,958, 5,112,846, 5,104,656,
5,098,613, 5,095,037, 5,095,019, 5,086,064, 5,081,261, 5,081,147, 5,081,126,
5,075,330, 5,066,668, 5,059,602, 5,043,457, 5,037,835, 5,037,811, 5,036,088,
5,013,850, 5,013,751, 5,013,736, 500,654, 4,992,448, 4,992,447, 4,988,733,
4,988,728, 4,981,865, 4,962,119, 4,959,378, 4,954,519, 4,945,099, 4,942,236,
4,931,457, 4,927,835, 4,912,248, 4,910,192, 4,904,786, 4,904,685, 4,904,674,
4,904,671, 4,897,397, 4,895,953, 4,891,370, 4,870,210, 4,859,686, 4,857,644,
4,853,392, 4,851,412, 4,847,303, 4,847,290, 4,845,242, 4,835,166, 4,826,990,
4,803,216, 4,801,598, 4,791,129, 4,788,205, 4,778,818, 4,775,679, 4,772,703,
4,767,776, 4,764,525, 4,760,051, 4,748,153, 4,725,616, 4,721,712, 4,713,393,
4,708,966, 4,695,571, 4,686,235, 4,686,224, 4,680,298, 4,678,802, 4,652,564,
4,644,005, 4,632,923, 4,629,793, 4,614,741, 4,599,360, 4,596,828, 4,595,694,
4,595,686, 4,594,357, 4,585,755, 4,579,866, 4,578,390, 4,569,942, 4,567,201,
4,563,476, 4,559,348, 4,558,067, 4,556,672, 4,556,669, 4,539,326, 4,537,903,
4,536,503, 4,518,608, 4,514,415, 4,512,990, 4,501,755, 4,495,197, 4,493,839,
4,465,687, 4,440,779, 4,440,763, 4,435,420, 4,412,995, 4,400,534, 4,355,034,
4,335,141, 4,322,420, 4,275,064, 4,244,963, 4,235,908, 4,234,593, 4,226,887,
4,201,778, 4,181,720, 4,173,650, 4,173,634, 4,145,444, 4,128,664, 4,125,612,
4,124,726, 4,124,707, 4,117,135, 4,027,031, 4,024,284, 4,021,553, 4,021,550,
4,018,923, 4,012,527, 4,011,326, 3,998,970, 3,998,954, 3,993,763, 3,991,212,
3,984,405, 3,978,227, 3,978,219, 3,978,202, 3,975,543, 3,968,224, 3,959,368,
3,949,082, 3,949,081, 3,947,475, 3,936,450, 3,934,018, 3,930,005, 3,857,955,
3,856,962, 3,821,377, 3,821,401, 3,789,121, 3,789,123, 3,726,978, 3,694,471,
3,691,214, 3,678,169, 3,624,216;
immunosuppressive agents, as disclosed in U.S. Pat. Nos. 4,450,159,
4,450,159, 5,905,085, 5,883,119, 5,880,280, 5,877,184, 5,874,594, 5,843,452,
5,817,672, 5,817,661, 5,817,660, 5,801,193, 5,776,974, 5,763,478, 5,739,169,
5,723,466, 5,719,176, 5,696,156, 5,695,753, 5,693,648, 5,693,645, 5,691,346,
5,686,469, 5,686,424, 5,679,705, 5,679,640, 5,670,504, 5,665,774, 5,665,772,
5,648,376, 5,639,455, 5,633,277, 5,624,930, 5,622,970, 5,605,903, 5,604,229,
5,574,041, 5,565,560, 5,550,233, 5,545,734, 5,540,931, 5,532,248, 5,527,820,
5,516,797, 5,514,688, 5,512,687, 5,506,233, 5,506,228, 5,494,895, 5,484,788,
5,470,857, 5,464,615, 5,432,183, 5,431,896, 5,385,918, 5,349,061, 5,344,925,
5,330,993, 5,308,837, 5,290,783, 5,290,772, 5,284,877, 5,284,840, 5,273,979,
5,262,533, 5,260,300, 5,252,732, 5,250,678, 5,247,076, 5,244,896, 5,238,689,
5,219,884, 5,208,241, 5,208,228, 5,202,332, 5,192,773, 5,189,042, 5,169,851,
5,162,334, 5,151,413, 5,149,701, 5,147,877, 5,143,918, 5,138,051, 5,093,338,
5,091,389, 5,068,323, 5,068,247, 5,064,835, 5,061,728, 5,055,290, 4,981,792,
4,810,692, 4,410,696, 4,346,096, 4,342,769, 4,317,825, 4,256,766, 4,180,588,
4,000,275, 3,759,921;
analgesic agents, as disclosed in U.S. Pat. Nos. 5,292,736, 5,688,825,
5,554,789, 5,455,230, 5,292,736, 5,298,522, 5,216,165, 5,438,064, 5,204,365,
5,017,578, 4,906,655, 4,906,655, 4,994,450, 4,749,792, 4,980,365, 4,794,110,
4,670,541, 4,737,493, 4,622,326, 4,536,512, 4,719,231, 4,533,671, 4,552,866,
4,539,312, 4,569,942, 4,681,879, 4,511,724, 4,556,672, 4,721,712, 4,474,806,
4,595,686, 4,440,779, 4,434,175, 4,608,374, 4,395,402, 4,400,534, 4,374,139,
4,361,583, 4,252,816, 4,251,530, 5,874,459, 5,688,825, 5,554,789, 5,455,230,
5,438,064, 5,298,522, 5,216,165, 5,204,365, 5,030,639, 5,017,578, 5,008,264,
4,994,450, 4,980,365, 4,906,655, 4,847,290, 4,844,907, 4,794,110, 4,791,129,
4,774,256, 4,749,792, 4,737,493, 4,721,712, 4,719,231, 4,681,879, 4,670,541,
4,667,039, 4,658,037, 4,634,708, 4,623,648, 4,622,326, 4,608,374, 4,595,686,
4,594,188, 4,569,942, 4,556,672, 4,552,866, 4,539,312, 4,536,512, 4,533,671,
4,511,724, 4,440,779, 4,434,175, 4,400,534, 4,395,402, 4,391,827, 4,374,139,
4,361,583, 4,322,420, 4,306,097, 4,252,816, 4,251,530, 4,244,955, 4,232,018,
4,209,520, 4,164,514 4,147,872, 4,133,819, 4,124,713, 4,117,012, 4,064,272,
4,022,836, 3,966,944;
cholinergic agents, as disclosed in U.S. Pat. Nos. 5,219,872, 5,219,873,
5,073,560, 5,073,560, 5,346,911, 5,424,301, 5,073,560, 5,219,872, 4,900,748,
4,786,648, 4,798,841, 4,782,071, 4,710,508, 5,482,938, 5,464,842, 5,378,723,
5,346,911, 5,318,978, 5,219,873, 5,219,872, 5,084,281, 5,073,560, 5,002,955,
4,988,710, 4,900,748, 4,798,841, 4,786,648, 4,782,071, 4,745,123, 4,710,508;
adrenergic agents, as disclosed in U.S. Pat. Nos. 5,091,528, 5,091,528,
4,835,157, 5,708,015, 5,594,027, 5,580,892, 5,576,332, 5,510,376, 5,482,961,
5,334,601, 5,202,347, 5,135,926, 5,116,867, 5,091,528, 5,017,618, 4,835,157,
4,829,086, 4,579,867, 4,568,679, 4,469,690, 4,395,559, 4,381,309, 4,363,808,
4,343,800, 4,329,289, 4,314,943, 4,311,708, 4,304,721, 4,296,117, 4,285,873,
4,281,189, 4,278,608, 4,247,710, 4,145,550, 4,145,425, 4,139,535, 4,082,843,
4,011,321, 4,001,421, 3,982,010, 3,940,407, 3,852,468, 3,832,470;
antihistamine agents, as disclosed in U.S. Pat. Nos. 5,874,479, 5,863,938,
5,856,364, 5,770,612, 5,702,688, 5,674,912, 5,663,208, 5,658,957, 5,652,274,
5,648,380, 5,646,190, 5,641,814, 5,633,285, 5,614,561, 5,602,183, 4,923,892,
4,782,058, 4,393,210, 4,180,583, 3,965,257, 3,946,022, 3,931,197;
steroidal agents, as disclosed in U.S. Pat. Nos. 5,863,538, 5,855,907,
5,855,866, 5,780,592, 5,776,427, 5,651,987, 5,346,887, 5,256,408, 5,252,319,
5,209,926, 4,996,335, 4,927,807, 4,910,192, 4,710,495, 4,049,805, 4,004,005,
3,670,079, 3,608,076, 5,892,028, 5,888,995, 5,883,087, 5,880,115, 5,869,475,
5,866,558, 5,861,390, 5,861,388, 5,854,235, 5,837,698, 5,834,452, 5,830,886,
5,792,758, 5,792,757, 5,763,361, 5,744,462, 5,741,787, 5,741,786, 5,733,899,
5,731,345, 5,723,638, 5,721,226, 5,712,264, 5,712,263, 5,710,144, 5,707,984,
5,705,494, 5,700,793, 5,698,720, 5,698,545, 5,696,106, 5,677,293, 5,674,861,
5,661,141, 5,656,621, 5,646,136, 5,637,691, 5,616,574, 5,614,514, 5,604,215,
5,604,213, 5,599,807, 5,585,482, 5,565,588, 5,563,259, 5,563,131, 5,561,124,
5,556,845, 5,547,949, 5,536,714, 5,527,806, 5,506,354, 5,506,221, 5,549,907,
5,491,136, 5,478,956, 5,426,179, 5,422,262, 5,391,776, 5,382,661, 5,380,841,
5,380,840, 5,380,839, 5,373,095, 5,371,078, 5,352,809, 5,344,827, 5,344,826,
5,338,837, 5,336,686, 5,292,906, 5,292,878, 5,281,587, 5,272,140, 5,244,886,
5,236,912, 5,232,915, 5,219,879, 5,218,109, 5,215,972, 5,212,166, 5,206,415,
5,194,602, 5,166,201, 5,166,055, 5,126,488, 5,116,829, 5,108,996, 5,099,037,
5,096,892, 5,093,502, 5,086,047, 5,084,450, 5,082,835, 5,081,114, 5,053,404,
5,041,433, 5,041,432, 5,034,548, 5,032,586, 5,026,882, 4,996,335, 4,975,537,
4,970,205, 4,954,446, 4,950,428, 4,946,834, 4,937,237, 4,921,846, 4,920,099,
4,910,226, 4,900,725, 4,892,867, 4,888,336, 4,885,280, 4,882,322, 4,882,319,
4,882,315, 4,874,855, 4,868,167, 4,865,767, 4,861,875, 4,861,765, 4,861,763,
4,847,014, 4,774,236, 4,753,932, 4,711,856, 4,710,495, 4,701,450, 4,701,449,
4,689,410, 4,680,290, 4,670,551, 4,664,850, 4,659,516, 4,647,410, 4,634,695,
4,634,693, 4,588,530, 4,567,000, 4,560,557, 4,558,041, 4,552,871, 4,552,868,
4,541,956, 4,519,946, 4,515,787, 4,512,986, 4,502,989, 4,495,102;
the disclosures of which are herein incorporated by reference.
The drug moiety of the bifunctional molecule may be the whole compound or a
binding fragment or portion thereof that retains its affinity and
specificity for the target of interest while having a linkage site for
covalent bonding to the presenter protein ligand or linker.
Presenter Protein Ligand: Z
Z is a ligand for a presenter protein present in the host into which the
bifunctional molecule is to be administered. The presenter protein ligand of
the subject bifunctional molecules binds to a specific presenter protein
present in the host. The binding interaction between the presenter protein
and the presenter protein ligand is non-covalent, such that no covalent
bonds are produced between the bifunctional molecule and the presenter
protein upon binding of the two entities. The presenter protein ligand is
small, where the size of the presenter protein ligand does not exceed about
4950 daltons, usually does not exceed about 4925 daltons and more usually
does not exceed about 4900 daltons, where the size of the presenter protein
ligand is generally at least about 50 daltons and more usually at least
about 100 daltons. The presenter protein ligand, in the context of the
bifunctional molecule, has substantially no pharmacological activity at its
effective concentration beyond binding to the presenter protein, i.e. it
does not directly cause a presenter protein-mediated pharmacological event
to occur upon binding at its effective concentration to the presenter
protein, where a presenter protein-mediated pharmacological event is a
pharmacologically relevant event which is directly modulated by the
presenter protein in the absence of the subject bifunctional molecules. As
used herein, pharmacological event is an event that is distinct from a
biochemical event (e.g. inhibition a prolyl isomerase activity) or a
biological event (e.g. inducement of a cell to express new genes).
The presenter protein to which the ligand of the bifunctional molecule binds
may be any protein that is present in the host at the time the bifunctional
molecule is introduced to the host, i.e. the presenter protein will be
endogenous to the host. The presenter protein may or may not have one or
more modified residues, e.g. residues that are glycosylated, such that the
presenter protein may or may not be a glycoprotein. Furthermore, the
presenter protein that is recruited by the bifunctional molecule may or may
not be part of a complex or structure of a plurality of biological
molecules, e.g. lipids, where such complexes or structures may include
lipoproteins, lipid bilayers, and the like. However, in many embodiments,
the presenter protein that is recruited by the presenter protein ligand of
the bifunctional molecule will be by itself, i.e. will not be part of a
larger structure of a plurality of biological molecules. Though the
presenter protein may be a protein that is not native to the host but has
been introduced at some time prior to introduction of the bifunctional
molecule, e.g. through prior administration of the protein or a nucleic acid
composition encoding the same, such as through gene therapy, the presenter
protein will, in many embodiments, be a protein that is native to and
naturally expressed by at least some of the host's cells, i.e. a naturally
occurring protein in the host. The presenter protein is a protein that is
present in the region of host occupied by the drug target. As such, where
the drug target is an intracellular drug target, the presenter protein will
be an intracellular protein present in the cell comprising the target,
typically expressed in the cell comprising the target, i.e. the presenter
protein and target are co-expressed in the same cell. Likewise, where the
drug target is an extracellular drug target, the presenter protein will be
an extracellular protein that is found in the vicinity of the target.
Although not a requirement in certain embodiments, in many preferred
embodiments the presenter protein is one that is present in the host in
sufficient quantities such that, upon binding of at least a portion of
presenter protein present in the host to the bifunctional molecule, adverse
pharmacological effects do not occur. In other words, the presenter protein
in these preferred embodiments is one in which its native and desirable
biological activity, if any, is not diminished by an unacceptable amount
following binding of the portion of the presenter protein population to the
bifunctional molecule. The amount of diminished activity of the presenter
protein that is acceptable in a given situation is determined with respect
to the condition being treated in view of the benefits of treatment versus
the reduction of overall presenter protein activity, if any. In certain
situations, a large decrease in overall presenter protein activity may be
acceptable, e.g. where the presenter protein activity aggravates the
condition being treated.
Specific presenter proteins of interest include intracellular and
extracellular proteins. Intracellular proteins of interest include:
peptidyl-prolyl isomerases, e.g. FKBPs and cyclophilins; ubiquitously
expressed molecular chaperones, e.g. Heat Shock Protein 90 (Hsp90); steroid
hormone receptors, e.g. estrogen receptors, glucocorticoid receptors,
androgen receptors; retinoic acid binding protein, cytoskeletal proteins,
such as tubulin and actin; etc.
Of particular interest as intracellular presenter proteins are cis-trans
peptidyl-prolyl isomerases which interact with many proteins-because of
their chaperonin/isomerase activity, e.g. FKBPs and cyclophilins.
Peptidyl-prolyl isomerases of interest include FKBPs. A number of different
FKBPs are known in the art, and include those described in: Sabatini et al.,
Mol. Neurobiol. (October 1997) 15:223-239; Marks, Physiol. Rev. (July 1996)
76:631-649; Kay, Biochem J. (March, 1996) 314: 361-385; Braun et al., FASEB
J. (January 1995) 9:63-72; Fruman et al, FASEB J. (April 1994) 8:391-400;
and Hacker et al., Mol. Microbiol. (November 1993) 10: 445-456. FKBPs of
interest include FKBP 12, FKBP 52, FKBP 14.6 (described in U.S. Pat. No.
5,525,523, the disclosure of which is herein incorporated by reference);
FKBP 12.6 (described in U.S. Pat. No. 5,457,182 the disclosure of which is
herein incorporated by reference); FKBP 13 (described in U.S. Pat. No.
5,498,597, the disclosure of which is herein incorporated by reference); and
HCB (described in U.S. Pat. No. 5,196,352 the disclosure of which is herein
incorporated by reference); where FKBP 12 and FKBP 52 are of particular
interest as intracellular presenter proteins.
Also of specific interest as presenter proteins are cyclophilins. A number
of cyclophilins are known in the art and are described in Trandinh et al.,
FASEB J. (December 1992) 6: 3410-3420; Harding et al., Transplantation
(August 1988) 46: 29S-35S. Specific cyclophilins of interest as
intracellular presenter proteins include cyclophilin A, B, C, D, E, and the
like, where cyclophilin A is of particular interest.
Instead of being an intracellular protein, the endogenous presenter protein
may be an extracellular or serum protein. Serum presenter proteins of
particular interest are those that are relatively abundant in the serum of
the host and meet the above criteria for suitable endogenous presenter
proteins. By relatively abundant is meant that the concentration of the
serum presenter protein is at least about 1 ng/ml, usually at least about 10
g/ml and more usually at least about 15 g/ml. Specific serum proteins of
interest as presenter proteins include: albumin, Vitamin A binding proteins
and Vitamin D binding proteins, -2 macroglobulin, with albumin being a
particularly preferred presenter protein.
The Z moiety of the subject bifunctional molecules will therefore be chosen
in view of the endogenous presenter protein that is to be recruited to
produce the at least binary and, in some embodiments, tripartite complex. As
such, the Z moiety may be a number of different ligands, depending on the
particular endogenous presenter protein to which it is intended to bind. In
many preferred embodiments, the Z moiety has an affinity for its presenter
protein of at least about 10.sup.-4 M, usually at least about 10.sup.-6
molar and more usually at least about 10.sup.-8 M, where in many embodiments
the Z moiety has an affinity for its presenter protein of between about
10.sup.-9 and 10.sup.-12 M. The Z moiety portion of the bifunctional
molecule should also be specific for the presenter protein in the context of
its binding activity when present in the bifunctional molecule, in that it
does not significantly bind or substantially affect non-presenter proteins
when it is present in the bifunctional molecule.
Representative ligands capable of serving as the Z moiety of the
bifunctional molecule include ligands for intracellular proteins, such as:
peptidyi-prolyl isomerase ligands, e.g. FK506, rapamycin, cyclosporin A and
the like; Hsp90 ligands, e.g. geldanamycin; steroid hormone receptor ligands,
e.g. naturally occurring steroid hormones, such as estrogen, progestin,
testosterone, and the like, as well as synthetic derivatives and mimetics
thereof, particularly those which bind with high specificity and affinity
but do not activate their respective receptors; small molecules that bind to
cytoskeletal proteins, e.g. antimitotic agents, such as taxanes, coichicine,
colcemid, nocadozole, vinblastine, and vincristine, actin binding agents,
such as cytochalasin, latrunculin, phalloidin, and the like.
As mentioned above, the preferred intracellular presenter proteins are
members of the peptidyl-prolyl isomerase family, particularly the FKBP and
cyclophilin subsets of this family. Where peptidyl-prolyl isomerase
presenter proteins are employed, the bifunctional molecule/peptidyl-prolyl
isomerase complex will preferably not substantially bind to the natural
peptidyl-prolyl isomerase/ligand target calcineurin so as to result in
significant immunosuppression. A variety of ligands are known that bind to
FKBPs and may be used in the subject invention. The ligands should
specifically bind to an FKBP and have an affinity for the FKBP that is
between about 10.sup.-6 and 10.sup.-10 M. Of interest are both naturally
occurring FKBP ligands, including FK506 and rapamycin. Also of interest are
synthetic FKBP ligands, including those described in U.S. Pat. Nos.:
5,665,774; 5,622,970; 5,516,797; 5,614,547; and 5,403,833, the disclosures
of which are herein incorporated by reference.
Also of interest are cyclophilin ligands, where such ligands should
specifically bind to cyclophilin with an affinity that is between about
10.sup.-6 and 10.sup.-9 M. A variety of ligands that bind to cyclophilins
are also known, where such ligands include the naturally occurring
cyclosporins, such as cyclosporin A, as well as synthetic derivatives and
mimetics thereof, including those described in U.S. Pat. Nos.: 5,401,649;
5,318,901; 5,236,899; 5,227,467; 5,214,130; 5,122,511; 5,116,816; 5,089,390;
5,079,341; 5,017,597; 4,940,719; 4,914,188; 4,885,276; 4,798,823; 4,771,122;
4,703,033; 4,554,351; 4,396,542; 4,289,851; 4,288,431; 4,220,61 and
4,210,581, the disclosures of which are herein incorporated by reference.
Representative ligands for use as the Z moiety in the bifunctional molecule
also include ligands that bind to extracellular presenter proteins. Such
ligands should specifically bind to their respective presenter protein with
an affinity of at least about 10.sup.-4M. Ligands of interest for use in
binding to extracellular presenter proteins include: albumin ligands, such
as arachidonate, bilirubin, hemin, aspirin, ibuprofen, para-amino salicylic
acid, myristylate, plamitate, linoleate, warfarin etc.; Vitamin A and
derivatives thereof, Vitamin D and derivatives thereof, and the like.
Linking Moiety: L
The Z and X moieties of the bifunctional molecule are joined together
through linking moiety L, where L may be either a bond or a linking group.
Where linking groups are employed, such groups are chosen to provide for
covalent attachment of the drug and ligand moieties through the linking
group, as well as the desired structural relationship of the bifunctional
molecule with respect to its intended presenter protein. Linking groups of
interest may vary widely depending on the nature of the drug and ligand
moieties. The linking group, when present, should preferably be biologically
inert. Appropriate linkers can readily be identified using the affinity,
specificity or selectivity assays described supra. A variety of linking
groups are known to those of skill in the art and find use in the subject
bifunctional molecules. The linker groups should be sufficiently small so as
to provide a bifunctional molecule having the overall size characteristics
as described above, the size of the linker group, when present, is generally
at least about 50 daltons, usually at least about 100 daltons and may be as
large as 1000 daltons or larger, but generally will not exceed about 500
daltons and usually will not exceed about 300 daltons. Generally, such
linkers will comprise a spacer group terminated at either end with a
reactive functionality capable of covalently bonding to the drug or ligand
moieties. Spacer groups of interest possibly include aliphatic and
unsaturated hydrocarbon chains, spacers containing heteroatoms such as
oxygen (ethers such as polyethylene glycol) or nitrogen (polyamines),
peptides, carbohydrates, cyclic or acyclic systems that may possibly contain
heteroatoms. Spacer groups may also be comprised of ligands that bind to
metals such that the presence of a metal ion coordinates two or more ligands
to form a complex. Specific spacer elements include: 1,4-diaminohexane,
xylylenediamine, terephthalic acid, 3,6-dioxaoctanedioic acid,
ethylenediamine-N,N-diacetic acid,
1,1'-ethylenebis(5-oxo-3-pyrrolidinecarboxylic acid),
4,4'-ethylenedipiperidine. Potential reactive functionalities include
nucleophilic functional groups (amines, alcohols, thiols, hydrazides),
electrophilic functional groups (aldehydes, esters, vinyl ketones, epoxides,
isocyanates, maleimides), functional groups capable of cycloaddition
reactions, forming disulfide bonds, or binding to metals. Specific examples
include primary and secondary amines, hydroxamic acids, N-nydroxysuccinimidyl
esters, N-hydroxysuccinimidyl carbonates, oxycarbonylimidazoles,
nitrophenylesters, trifluoroethyl esters, glycidyl ethers, vinylsulfones,
and maleimides. Specific linker groups that may find use in the subject
bifunctional molecules include heterofunctional compounds, such as
azidobenzoyl hydrazide, N-[4-(p-azidosalicylamino)butyl]-3'-[2'-pyridyldithio]propionamid),
bis-sulfosuccinimidyl suberate, dimethyladipimidate, disuccinimidyltartrate,
N-maleimidobutyryloxysuccinimide ester, N-hydroxy
sulfosuccinimidyl-4-azidobenzoate, N-succinimidyl
[4-azidophenyl]-1,3'-dithiopropionate, N-succinimidyl
[4-iodoacetyl]aminobenzoate, glutaraldehyde, and succinimidyl
4-[N-maleimidomethyl]cyclohexane-1-carboxyiate, 3-(2-pyridyldithio)propionic
acid N-hydroxysuccinimide ester (SPDP),
4-(N-maleimidomethyl)-cyclohexane-1-carboxylic acid N-hydroxysuccinimide
ester (SMCC), and the like.
Methods of Making Bifunctional Molecules
The bifunctional molecules of the subject invention may be prepared using
any convenient methodology. In many embodiments of the subject invention,
the invention is used to improve one or more aspects of an identified and at
least partially characterized small molecule drug. Generally, a small
molecule drug of interest but lacking in some of the desired biological
activities, such as affinity, specificity or selectivity, is first
identified. The drug may be a previously identified biologically active
agent or compound having the desired target binding activity, or one that
has been newly discovered using one or more drug discovery techniques. The
bifunctional molecule is then generally produced from the drug using a
rational or combinatorial approach.
In a rational approach, the bifunctional molecules are constructed from
their individual components, e.g. ligand, linker and drug. The components
can be covalently bonded to one another through functional groups, as is
known in the art, where such functional groups may be present on the
components or introduced onto the components using one or more steps, e.g.
oxidation reactions, reduction reactions, cleavage reactions and the like.
Functional groups that may be used in covalently bonding the components
together to produce the bifunctional molecule include: hydroxy, sulfhydryl,
amino, and the like. The particular portion of the different components that
are modified to provide for covalent linkage will be chosen so as not to
substantially adversely interfere with that components desired binding
activity, e.g. for the drug moiety, a region that does not affect the target
binding activity will be modified, such that a sufficient amount of the
desired drug activity is preserved. Where necessary and/or desired, certain
moieties on the components may be protected using blocking groups, as is
known in the art, see, e.g. Green & Wuts, Protective Groups in Organic
Synthesis (John Wiley & Sons) (1991).
The above component approach to production of the bifunctional molecule is
best suited for situations where the crystal structures of the presenter
protein, ligand, drug and target are known, such that molecular modeling can
be used to determine the optimal linker size, if any, to be employed to join
the different components.
Alternatively, the bifunctional molecule can be produced using combinatorial
methods to produce large libraries of potential bifunctional molecules which
may then be screened for identification of a bifunctional molecule with the
desired binding affinity and/or specificity. Methods for producing and
screening combinatorial libraries of molecules include: U.S. Pat. Nos.
5,741,713; 5,734,018; 5,731,423; 5,721,099; 5,708,153; 5,698,673; 5,688,997;
5,688,696; 5,684,711; 5,641,862; 5,639,603; 5,593,853; 5,574,656; 5,571,698;
5,565,324; 5,549,974; 5,545,568; 5,541,061; 5,525,735; 5,463,564; 5,440,016;
5,438,119; 5,223,409, the disclosures of which are herein incorporated by
reference.
Alternatively, the bifunctional molecule may be produced using medicinal
chemistry and known structure-activity relationships for the presenter
protein ligand and the drug. In particular, this approach will provide
insight as to where to join the two moieties to the linker.
Screening Bifunctional Compounds
The resultant bifunctional molecules are then screened for those molecules
that exhibit at least one of enhanced affinity, specificity or selectivity
as compared to that observed for the free drug. Any convenient screening
assay may be employed, where the particular screening assay may be one known
to those of skill in the art or one developed in view of the specific
molecule and property being studied. Typically, the screening assay will
involve observing the binding activity of the bifunctional molecule to the
target in the presence of an appropriate presenter protein. For example,
where one is interested in identifying those bifunctional molecules that
exhibit enhanced affinity for their targets as compared to the free drug,
one can conduct binding assays and select those bifunctional molecules that
exhibit enhanced affinity, where the affinity will generally be at least
about 2 fold greater than that observed for the free drug, as described
above. For specificity, an assay can be used that focuses on the binding of
the bifunctional molecule to both desirable and undesirable targets. For
example, where one is interested in identifying those bifunctional molecules
that exhibit improved specificity as compared to the corresponding free
drug, where the free drug binds to both desirable target A and undesirable
target B, one can screen the library for those bifunctional molecules that,
in the presence of presenter protein, bind to target A but with reduced
amounts, if at all, to target B, as such bifunctional molecules are more
specific for the desired target than free drug. For selectivity, an assay
can be used to compare the activity of a bifunctional molecule in the target
cell or tissue type to the activity of the bifunctional molecule in cells or
tissues in which drug activity is not desired. A selective bifunctional
molecule will affect the target in the desired cells, e.g. cells involved in
a disease process, but it will not affect (or at least affect to a lesser
extent) the target in undesired cells, e.g. cells not involved in the
disease process. For example, a prospective drug may bind to target A in
both the host and a pathogenic microorganism. By adding a ligand for a
presenter protein to the drug, target A in the host is unable to bind the
drug due to interactions with the presenter protein, while the drug retains
its potency in the microorganism.
Methods of Making Bifunctional Molecules for Peptidyl-Prolyl Isomerase
Presenter Proteins
As mentioned above, one class of preferred embodiments of the subject
invention are those embodiments in which the bifunctional molecules
specifically bind to endogenous peptidyl-prolyl isomerase presenter proteins
present in the host into which the bifunctional molecule is introduced.
Thus, bifunctional molecules of interest include those in which the
endogenous presenter protein is either an FKBP or a cyclophilin.
In preparing bifunctional molecules from FK506, a suitable attachment site
on the FK506 structure is identified, modified as necessary, and then
covalently attached to the linker or drug moiety. The structure of FK506
(also known as tacrolimus) is -- see Original Patent.
The site to which the
linker/drug moiety is covalently attached is one that, upon covalent
attachment, does not ablate the affinity and/or specificity of FK506 for its
FKBP presenter protein, e.g. FKBP 12 or FKBP 52. As such, positions suitable
for use as covalent linkage sites include atoms located between carbon 15
and carbon 25 and the substituents attached to these atoms. For example,
oxidation of the allyl group or oxidation of the carbon 18 methylene group;
modification of the carbon 22 ketone or the carbon 24 hydroxyl group or
alkylation at carbon 21 or carbon 23; as well as the secondary hydroxyl
group located on the cyclohexyl ring (carbon 32); are potential specific
covalent linkage sites.
With FK506, depending on the drug moiety and/or linker to be attached, it
may be desirable to introduce one or more functional moieties onto the FK506
structure. Functional moieties of interest that may be introduced include:
hydroxyl groups, amino groups, carboxyl groups, aldehydes, carbonates,
carbamates, azides, thiols, and esters, etc. Such groups may be introduced
using known protocols, such as oxidation reactions, reduction reactions,
cleavage reactions and the like, with or without the use of one or more
blocking groups to prevent unwanted side reactions.
In some instances, it is desirable to covalently attach the drug moiety
directly to FK506, often activated FK506. In such instances, the reactive
functional group(s) introduced onto the FK506 structure will depend
primarily on the nature of the drug moiety to be attached. Thus, for
peptidic drug moieties, specific pairings of interest include: FK506
carbonates for reacting with amino groups of peptides; FK506 carboxylic
acids for reacting with amino groups of peptides; FK506 amines for reacting
with carboxylic acid groups of peptides; FK506 maleimide for reacting with
thiol groups of peptides; and the like. Alternatively, where the drug moiety
is a steroid, potential pairings of interest include: FK506 N-hydroxysuccinimidyl
carbonate and partner amine; FK506 aldehyde and partner amine; FK506
aldehyde and partner hydrazide; FK506 hydroxy group and partner carboxylic
acid OR alkyl halide; FK506 thiol and partner maleimide and the like.
Following introduction of the reactive functional group(s) onto the FK506
structure, the activated FK506 is then combined with the drug moiety/linker
under conditions sufficient for covalent bonding to occur.
Another embodiment of particular interest are bifunctional molecules of
cyclosporin A or analogs thereof. The structure of cyclosporin A is -- see Original Patent.
As with the FK506 bifunctional molecules, the cyclosporin A will be
conjugated to the drug moiety in a manner such that cyclosporin A does not
substantially lose its affinity for cyclophilin. Preferred positions on the
cyclosporin A structure that may serve as covalent linkage sites include:
residues 4, 5, 6, 7, 8; while less preferred but still possible residues
include: 1, 2, 3, 9, 10 and 11. Where necessary, reactive functionalities
may be introduced onto the cyclosporin structure, where such functionalities
include: hydroxyl groups, amino groups, carboxyl groups, aldehydes,
carbonates, carbamates, azides, thiols, and esters, etc., with the
particular functionality of interest being chosen with respect to the
specific linker or drug moiety to be attached.
Specific Improvements as Compared to Free Drug
As mentioned above, the bifunctional molecules of the subject invention
provide for specific improvements over the overall activity observed in the
corresponding free drug, i.e. the bifunctional molecules exhibit at least
one of enhanced affinity, specificity or selectivity as compared to free
drug, i.e. a free drug control. Though not wishing to be bound to any
particular theory, the improved activity as compared to free drug is thought
to result from the enlarged target binding surface present on the binary
complex or optimization of favorable interactions as compared to that found
on the free drug. In other words, presentation of the drug as a binary
complex of the bifunctional molecule and its presenter protein modulates the
overall binding profile of the drug moiety with respect to its targets in a
way that improves at least one of the affinity, specificity or selectivity
of the drug as compared to a free drug control. This modulation of binding
profile can result from the combination of drug-target interactions and
presenter protein-drug target interactions, where the presenter protein-drug
target interactions may be attractive, repulsive or neutral.
FIG. 1A (see Original Patent) provides a representation of how enhanced
affinity is achieved with the subject invention. As shown, the drug target
establishes favorable or attractive protein-protein interactions with a
presenter protein that presents the drug moiety of the bifunctional
compound. These favorable interactions between the presenter protein and the
drug target enhance the affinity of the drug for its target. FIG. 1B (see Original Patent)
provides a representation of how enhanced specificity is achieved with the
subject bifunctional compounds. In FIG. 1B, a non-specific drug binding
protein (i.e. an undesirable target) cannot bind the drug moiety in the
context of the presenter protein because of unfavorable protein-protein
interactions between the presenter protein and the non-specific drug binding
protein. As such, enhanced specificity is observed since the drug can only
bind to its bona fide drug target. FIG. 1C (see Original Patent) provides a
representation of how enhanced selectivity is achieved with the subject
bifunctional compounds, where activity of the drug is limited to one type of
cell or another within an organism.
Thus, in a first preferred embodiment, the bifunctional molecule provides
for enhanced or greater affinity for the target as compared to the free
drug. In preferred embodiments of the subject invention, the enhanced
affinity results from positive, i.e. attractive, interactions between the
presenter and target as well as between the drug and target. As such,
improved affinity results from the production of a tripartite complex
characterized by the presence of both drug/target binding interactions and
presenter/target binding interactions.
In a second preferred embodiment of the subject invention, the bifunctional
molecule provides enhanced specificity as compared to the free drug. In such
situations, the bifunctional molecule/presenter protein binary complex
exhibits negative or repulsive interactions with at least some, if not all,
of the free drug's targets but not for the desired target, where any
repulsive or negative interactions arising from the presentation of the drug
moiety in the context of the presenter protein are insufficient to prevent a
suitable amount of binding of drug to the desired target. Thus, tripartite
complexes produced between the binary complex and undesired targets are, in
at least some cases, characterized by the presence of negative or repulsive
interactions. Administration of the drug as a bifunctional molecule
according to the subject invention provides for the desired activity,
without the undesirable activity that arises from the low specificity of the
free drug.
In a third embodiment of the subject invention, the bifunctional molecule
provides for enhanced selectivity as compared to the free drug. In this
embodiment, the bifunctional molecule exhibits activity in a first type of
cell but not in a second type of cell. This selective activity is based on
the formation of a binary complex between the bifunctional molecule and a
presenter protein ligand that is present in a first type of cell but not in
a second type of cell. Depending on the particular bifunctional molecule and
drug target, the drug moiety may only exhibit activity when presented to the
target in the form of a binary complex with the presenter protein.
Conversely, the drug moiety may exhibit activity only when presented to the
drug target as the bifunctional molecule by itself.
As such, in certain embodiments, the bifunctional molecule is engineered to
have a presenter protein ligand that binds to a presenter protein present
only in those cells that harbor the desired drug target, where activity of
the drug moiety is at least enhanced when it is presented to the drug target
by the presenter protein. Those cells which harbor the undesired target also
lack the presenter protein. As such, the drug moiety of the bifunctional
molecule exhibits less activity in these cells since it is not presented by
a presenter protein to the drug target. In this manner, the activity of the
drug moiety has been selectively enhanced in the first type of cell that
comprises the desired drug target and presenter protein as compared to the
second type of cell that harbors the undesired drug target and lacks the
presenter protein.
In other embodiments, the drug of interest is one that binds in its free
drug state to a desired target in a first type of cell but also to an
undesired target in a second type of cell. Examples of such drugs include
antimicrobial agents, such as antibiotics, which bind to desirable targets
in microorganisms but undesirable targets in other types of cells, such as
host cells in which the microorganism is present. In this embodiment, the
bifunctional molecule is one that comprises a ligand for a presenter protein
that is present in those cells comprising the undesirable target(s) but is
not present in those cells harboring the desired target. In other words, the
presenter ligand Z of the bifunctional molecule may be any ligand that binds
to a protein present in those cells comprising the undesirable target but
not present in those cells that have the desired target. The particular
presenter ligand that is employed will necessarily depend on the nature of
the two types of cells among which differentiation in drug activity is
desired. For example, where the two types of cells are microbial and human
cells, the presenter protein ligand may be one that binds to a protein that
is present in the human cells but not present in the microbial cells, e.g.
FKBPs, and the like. The bifunctional molecule/presenter protein binary
complex is unable to bind to the undesirable targets in those cells that do
not comprise the desired target. At the same time, the free bifunctional
molecule is able to bind to the desired target in those cells that comprise
the desired target because of repulsive interactions between the binary
complex and the undesirable target. For example, where the drug moiety is a
particular antibiotic that exhibits desired activity in bacterial cells but
undesirable activity in human cells, the bifunctional molecule is able to
bind to the bacterial target but the bifunctional molecule/binary complex is
not able to bind to the human target(s). See FIG. 1C. As such, the
bifunctional molecule provides for enhanced selectivity as compared to the
free drug.
Preferred drugs in this third embodiment are molecules which exhibit
considerable side effects and toxicity in human cells in addition to a
desired activity in target cells. Many of these molecules target metabolic
pathways and biological activities that are common to the target cell as
well as non-target cells, such as: inhibitors of RNA polymerase II like-aminitin,
rifamycin, rifampicin and actinomycin D; protein synthesis inhibitors like
cycloheximide, streptomycin, tetracycline, chloramphenicol, erythromycin or
puromycin; dihydrofolate reductase inhibitiors like methotrexate;
topoisomerase II inhibitors like novobiocin and ciprofloxacin, proteasome
inhibitors like lactacystin; channel inhibitors.
This embodiment finds particular use in the targeting of a drug to a
microbial pathogen while reducing toxicity to the host in which the
microbial pathogen is present. Microbial pathogens that may be targeted
include Legionella sp., Chlamydia sp., Staphylococcus sp., Neisseria sp.,
Rickettsia sp., Coxiella sp., Neurospora sp., Escherischia coli, Heliobacter
pylori as well as protozoan pathogens like Plasmodium sp., Leishmania sp.,
Trypanosoma sp., Entamoeba histolytica, Giardia lamblia, Trichomonas
vaginalis.
In one particular embodiment of interest, the drug is selected from the
group consisting of methotrexate and puromycin which are linked to a
presenter ligand such that DHFR and protein synthesis, respectively, are
less affected in cells containing the presenter protein (e.g. FKBP), e.g.
host cells, than in cells that lack the presenter, e.g. pathogen cells.
Methods of Use, Pharmaceutical Preparations and Kits
The subject bifunctional molecules find use in producing at least binary
complexes in vivo, where the production of these complexes is desirous to
the host in which they occur, e.g. is beneficial to the host. The term
binary complex is used throughout this specification to refer to any complex
produced by the non-covalent binding of two distinct molecules, i.e. the
bifunctional molecule and the presenter protein or the bifunctional molecule
and the protein target. In many preferred embodiments, tripartite complexes
are produced with the subject bifunctional molecules. The term tripartite
complex is used throughout this specification to refer to binding complexes
of three distinct entities, i.e. the protein drug target, the bifunctional
molecule and the presenter protein.
In the methods of the subject invention, an effective amount of the
bifunctional molecule is administered to the host, where "effective amount"
means a dosage sufficient to produce the desired result, e.g. an improvement
in a disease condition or the symptoms associated therewith. The
bifunctional molecule may be administered to the host using any convenient
means capable of producing the desired result. Thus, the bifunctional
molecule can be incorporated into a variety of formulations for therapeutic
administration. More particularly, the bifunctional molecule of the present
invention can be formulated into pharmaceutical compositions by combination
with appropriate, pharmaceutically acceptable carriers or diluents, and may
be formulated into preparations in solid, semi-solid, liquid or gaseous
forms, such as tablets, capsules, powders, granules, ointments, solutions,
suppositories, injections, inhalants and aerosols. As such, administration
of the bifunctional molecule can be achieved in various ways, including
oral, buccal, rectal, parenteral, intraperitoneal, intradermal, transdermal,
intracheal, etc., administration. In pharmaceutical dosage forms, the
bifunctional molecule may be administered alone or in combination with other
pharmaceutically active compounds. The following methods and excipients are
merely exemplary and are in no way limiting.
For oral preparations, the bifunctional molecules can be used alone or in
combination with appropriate additives to make tablets, powders, granules or
capsules, for example, with conventional additives, such as lactose,
mannitol, corn starch or potato starch; with binders, such as crystalline
cellulose, cellulose derivatives, acacia, corn starch or gelatins; with
disintegrators, such as corn starch, potato starch or sodium
carboxymethylcellulose; with lubricants, such as talc or magnesium stearate;
and if desired, with diluents, buffering agents, moistening agents,
preservatives and flavoring agents.
The bifunctional molecules can be formulated into preparations for injection
by dissolving, suspending or emulsifying them in an aqueous or nonaqueous
solvent, such as vegetable or other similar oils, synthetic aliphatic acid
glycerides, esters of higher aliphatic acids or propylene glycol; and if
desired, with conventional additives such as solubilizers, isotonic agents,
suspending agents, emulsifying agents, stabilizers and preservatives.
The bifunctional molecules can be utilized in aerosol formulation to be
administered via inhalation. The compounds of the present invention can be
formulated into pressurized acceptable propellants such as
dichlorodifluoromethane, propane, nitrogen and the like.
Furthermore, the bifunctional molecules can be made into suppositories by
mixing with a variety of bases such as emulsifying bases or water-soluble
bases. The compounds of the present invention can be administered rectally
via a suppository. The suppository can include vehicles such as cocoa
butter, carbowaxes and polyethylene glycols, which melt at body temperature,
yet are solidified at room temperature.
Unit dosage forms for oral or rectal administration such as syrups, elixirs,
and suspensions may be provided wherein each dosage unit, for example,
teaspoonful, tablespoonflul, tablet or suppository, contains a predetermined
amount of the composition containing active agent. Similarly, unit dosage
forms for injection or intravenous administration may comprise the active
agent in a composition as a solution in sterile water, normal saline or
another pharmaceutically acceptable carrier.
The term "unit dosage form," as used herein, refers to physically discrete
units suitable as unitary dosages for human and animal subjects, each unit
containing a predetermined quantity of compounds of the present invention
calculated in an amount sufficient to produce the desired effect in
association with a pharmaceutically acceptable diluent, carrier or vehicle.
The specifications for the novel unit dosage forms of the present invention
depend on the particular compound employed and the effect to be achieved,
and the pharmacodynamics associated with each compound in the host.
The pharmaceutically acceptable excipients, such as vehicles, adjuvants,
carriers or diluents, are readily available to the public. Moreover,
pharmaceutically acceptable auxiliary substances, such as pH adjusting and
buffering agents, tonicity adjusting agents, stabilizers, wetting agents and
the like, are readily available to the public.
Those of skill will readily appreciate that dose levels can vary as a
function of the specific compound, the severity of the symptoms and the
susceptibility of the subject to side effects. Preferred dosages for a given
compound are readily determinable by those of skill in the art by a variety
of means.
The subject methods find use in the treatment of a variety of different
disease conditions. In certain embodiments, of particular interest is the
use of the subject methods in disease conditions where an active agent or
drug having desired activity has been previously identified, but which
active agent or drug does not bind to its target with desired affinity
and/or specificity. With such active agents or drugs, the subject methods
can be used to enhance the binding affinity and/or specificity of the agent
for its target.
The specific disease conditions treatable by with the subject bifunctional
compounds are as varied as the types of drug moieties that can be present in
the bifunctional molecule. Thus, disease conditions include cellular
proliferative diseases, such as neoplastic diseases, autoimmune diseases,
cardiovascular diseases, hormonal abnormality diseases, infectious diseases,
and the like.
By treatment is meant at least an amelioration of the symptoms associated
with the disease condition afflicting the host, where amelioration is used
in a broad sense to refer to at least a reduction in the magnitude of a
parameter, e.g. symptom, associated with the pathological condition being
treated, such as inflammation and pain associated therewith. As such,
treatment also includes situations where the pathological condition, or at
least symptoms associated therewith, are completely inhibited, e.g.
prevented from happening, or stopped, e.g. terminated, such that the host no
longer suffers from the pathological condition, or at least the symptoms
that characterize the pathological condition.
A variety of hosts are treatable according to the subject methods. Generally
such hosts are "mammals" or "mammalian," where these terms are used broadly
to describe organisms which are within the class mammalia, including the
orders carnivore (e.g., dogs and cats), rodentia (e.g., mice, guinea pigs,
and rats), and primates (e.g., humans, chimpanzees, and monkeys). In many
embodiments, the hosts will be humans.
Kits with unit doses of the bifunctional molecule, usually in oral or
injectable doses and often in a storage stable formulation, are provided. In
such kits, in addition to the containers containing the unit doses will be
an informational package insert describing the use and attendant benefits of
the drugs in treating pathological condition of interest. Preferred
compounds and unit doses are those described herein above.
Claim 1 of 8 Claims
1. A method for producing a tripartite
complex in a host, said method comprising: administering to said host an
effective amount of a bifunctional molecule of less than about 5000
daltons consisting of a drug moiety linked to a ligand for a presenter
protein endogenous to said host, wherein said drug moiety binds to a drug
target and said ligand binds to a presenter protein that is not said drug
target; whereby said tripartite complex is produced by said ligand of the
bifunctional molecule binding to said presenter protein and said drug
moiety of said bifunctional molecule binding to said drug target, and said
drug moiety of said complex exhibits enhanced drug activity as compared to
said drug in free form. ____________________________________________
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