Patent Application
20050203016
Not applicable.
A written Sequence Listing and a computer readable form of the sequence listing, consisting of one file named ChimericHybridAnalgesics.ST25.txt on one disk, are attached as Appendices.
1. Field of the Invention
The present invention lies firmly within the fields of drug, bio-effective and body treating compositions, more specifically methods for drug delivery through selective targeting of biological tissues containing populations of receptor proteins.
2. Description of the Prior Art
The present invention relates to selective targeting of biological tissues containing populations of receptor proteins by using novel conjugate non-peptide/peptide molecules, which I call chimeric hybrid molecules. As described, the present invention embodies activation domains that are recognized by membrane-associated G-protein receptors for mu (μ) opioids or for the neuropeptide Substance P(SP).
From an established pharmacological perspective, opioids remain the key agents of choice for treatment of a wide variety of acute and chronic pain states. The prototype opioid analgesic or painkiller is morphine. Morphine and morphine-related opioids produce their painkilling effects by profound pharmacological inhibition of neurons of the peripheral/sensory nervous system (PNS) and the central nervous system (CNS). The biochemical and cellular effects of morphine, including profound analgesia, are transduced through a membrane-associated G-protein designated the mu (μ) opioid receptor (MOR), found in high concentrations within the PNS and CNS.
Unfortunately, the effects produced by morphine and similar opioid compounds make them amendable to abuse and are associated with many undesirable side effects, all mediated through activation of the MOR. They include physical and psychological dependence leading to addiction and other diverse pathophysiological states.
In addition to the adverse physiological sequelae listed above, a major associated risk is that repeated daily administrations of morphine or morphine-like opioids will eventually induce significant tolerance to the therapeutic effects of the drug as well as initiating some degree of physical dependence. Here opioid tolerance is operationally defined as an escalating dosage regimen required to achieve the same magnitude of pain relief over a defined time course.
The degree of tolerance and physical dependence will vary with the particular opioid employed, the correlation with MOR-selective opioids such as morphine being high, the frequency of administration, and the quantity of opioid administered.
In a wide variety of clinical indications requiring prolonged use of opioids, tolerance induction and addiction are closely linked, with the development of physical and psychological dependence always a major concern. Addiction with physical dependence can be difficult to treat due to the effects of withdrawal associated with dependence.
Receptors, such as MOR and SPR, exist in close proximity in the CNS and PNS. In my invention, Ser. No. 10/134,187, filed Apr. 26, 2002, I invented novel conjugate molecules, comprising a mammalian mu (μ) opioid receptor (MOR) agonist covalently linked to a mammalian substance P receptor (SPR) agonist, wherein one agonist is a peptide and one is a non-peptide. My invention included conjugates wherein the molecule induces analgesia when administered in a mammal with tolerance development markedly less that that of morphine.
In connection therewith I invented a method of drug delivery through selective targeting of biological tissues containing populations of receptor proteins. My method employs a novel conjugate molecule, comprised of a peptide and a non-peptide, to deliver a drug, such as Substance P, to a receptor moiety, such as the SPR, by targeting a nearby receptor site, such as the MOR, with another moiety, such as an opioid, with a novel flexible linker hinge permitting the delivered drug to activate its receptor when the targeting drug activates its receptor. My method similarly employs a novel conjugate molecule, comprised of a peptide and a non-peptide, to deliver a drug, such as an opioid, to a receptor moiety, such as the MOR, by targeting a nearby receptor site, such as the SPR, with another moiety, such as an SP fragment, with a novel flexible linker hinge permitting the delivered drug to activate its receptor when the targeting drug activates its receptor. The novel chimeric hybrid molecules and the method for using them to target drug delivery are unknown to the literature.
I have invented novel and useful methods employing heretofore unknown non-peptide/peptide conjugate molecules, or as I call them chimeric hybrids, as I have described below. Several objects and advantages of my present invention are:
Still further objects and advantages will become apparent from a consideration of the following description of my invention.
The present invention represents a novel method of drug delivery through selective targeting of biological tissues containing populations of receptor proteins using novel chimeric hybrid molecules containing a moiety that binds to and activates an MOR or a moiety that binds to and activates an SPR. The method targets the MOR or SPR and delivers a drug to a nearby receptor site activated by the other moiety, made possible through the use of a novel linker hinge.
These chimeric hybrid compounds can be used to selectively target biological tissues containing populations of MOR or SPR proteins. The hybrid non-peptide/peptide conjugate molecules may be administered systemically, intrathecally or more preferably, orally.
My method can be illustrated through several embodiments by which an opioid is used to target the delivery of SP to an SPR. In one embodiment, the independent functional domains consisting of chemically modified morphine and an SP fragment are covalently cross linked through the four carbon organic molecule succinic acid. In another embodiment, the independent functional domains consisting of chemically modified morphine and an SP fragment are covalently cross linked through the four carbon organic molecule gamma-hydroxy butyric acid. In another embodiment, the independent functional domains consisting of chemically modified morphine and a SP fragment are covalently cross linked through the six carbon carbohydrate d-glucuronic acid. The use of three such molecules, succinic acid, gamma-hydroxy butyric acid, and d-glucuronic acid, as molecular hinges to cross link two active pharmacological domains of disparate chemical nature, i.e., a multi-ringed opioid alkaloid structure and a linear peptide structure, is not intuitively obvious or predictable from the prior art. The use of succinic acid, gamma-hydroxy butyric acid, and d-glucuronic acid, as molecular hinges to cross link a pharmacologically active peptide to a pharmacologically active opioid is novel and unknown to the literature of analgesia and to clinical practice.
The chimeric hybrid molecule may be designed to have a plurality of moieties that activate SPRs or MORs. Examples of a pluarality of moieties that activate SPRs include moities consisting of pharmacologically active COOH-terminal fragments of SP. The plurality of SP fragments are each designed to bind to and activate an SPR. Examples of a plurality of moieties that activate MORs include moities such as morphine chemically modified at its 6′hydroxyl group. The plurality of opioid moieties are each designed to bind to and activate an MOR.
Because the MOR- and SPR-activating domains are of chemically different compositions, i.e., a multi-ringed alkaloid structure and a linear peptide structure, respectively, it is not intuitively obvious that they may be combined in a functionally active molecule. This is achieved, however, by incorporating a novel molecular hinge region consisting of succinic acid, or gamma-hydroxy butyric acid, or d-glucuronic acid.
The existence of functionally active chimeric hybrid molecules, of internally differing chemical nature, combining MOR- and other receptor protein activating domains, or SPR- and other receptor protein activating domains, linked by a novel molecular hinge, are unknown to the literature of analgesia and to clinical practice.
The invention provides a method for selectively targeting biological tissues containing populations of MOR or SPR proteins using pharmaceutical compositions including hybrid alkaloid chimeric molecules and a pharmaceutically acceptable carrier useful for the treatment of pain and pain-related patho-physiological disorders. It represents a method for selectively targeting biological tissues involved in integrating important physiological functions, such as by using novel hybrid alkaloid/peptide chimeric molecules containing an opioid and SP moiety designed to achieve coincident activation of populations of MORs and SPRs as a novel pharmaceutical analgesic treatment without tolerance and dependence. In the field of analgesia, the novel intrinsic targeting capabilities of my invention allow hybrid alkaloid/peptide analgesics to have marked reduction of effective dosages with commensurate reduction of undesirable side-effects. My method of drug delivery invention is not limited to coincident activation of SPRs and MORs and can be used to activate MORs and selected nearby receptors, or to activate SPRs and selected nearby receptors.
The invention therefore provides novel methods for selectively targeting biological tissues containing populations of MOR or SPR proteins using molecules heretofore unknown to the literature of analgesia or more generally to the literature of biochemical pharmacology. In these novel attributes, the method of selectively targeting biological tissues containing populations of MOR or SPR proteins using chimeric hybrid molecules differs substantially from prior art.
The method of selectively targeting biological tissues containing populations of MOR and SPR proteins encompassing administration of chimeric hybrid molecules with three chemically disparate functional domains, e.g., a ringed alkaloid MOR-activation domain, a peptide SPR-activation domain, and a flexible organic acid hinge domain, is unknown to the preclinical and clinical literature of pain and analgesia.
A desired objective of the present invention is that the chimeric hybrid molecules allow the targeting of nearby, functionally related receptor domains. In an embodiment of my invention, hybrid alkaloid/peptide chimeric molecules can be administered to produce opioid-associated pharmacological effects with little or no development of opioid tolerance due to their selective targeting of biological tissues containing populations of MOR and SPR proteins involved with pain modulation and with pain-related physiological processes.
Detailed descriptions of one or more embodiments of the invention are described below. The novelty of the invention, as amply described above, will be apparent from the detailed description of structure and synthesis and from the claims. In the specification and the appended claims, the singular forms include plural referents unless the context clearly dictates otherwise. All technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Unless expressly stated otherwise, the techniques employed or contemplated herein are standard methodologies well known to one of ordinary skill in the art. The examples of embodiments are for illustration purposes only. All patents and publications cited in this specification are incorporated herein by reference.
Description—
The present invention provides a method of novel drug delivery through selective targeting of biological tissues containing populations of MOR or SPR proteins using hybrid alkaloid chimeric molecules having an MOR binding and activation moiety and an SPR binding and activation moiety. The hybrid alkaloid/peptide chimeric molecules are designed to bind to and activate populations of MORs or SPRs or both, located primarily within the human biological tissues. In their embodiment as analgesic agents, the hybrid alkaloid chimeric molecules are designed to bind to and activate populations of MORs or SPRs located within nerves of the human CNS, but also in the human PNS, involved in pain mediation, analgesic responses, and related physiological processes.
In addition to nerves, human biological tissues include organs such as lung, stomach, intestine, kidney, bladder, liver, heart, blood, muscle, and bone. Hybrid alkaloid chimeric molecules are designed to bind to and activate populations of MORs or SPRs located within these additional biological tissues to modulate diverse physiological processes related to pain and analgesia and other essential function necessary for health and well-being. Biological tissues also include lesions and/or neoplasms of organs such as lung, stomach, intestine, kidney, bladder, liver, heart, blood, muscle, bone, and nerves. Hybrid alkaloid chimeric molecules are designed to bind to and activate populations of MORs or SPRs located within these organs to modulate diverse pathological processes involved in development and maintenance of disease states associated with interactive populations of MORs or SPRs and other receptor proteins.
While the alkaloid morphine and the peptide SP frequently exhibit slight cross reactivity to other opioid and tachykinin receptor types, respectively, they are generally characterized, as exhaustively detailed in the literature, by a very high degree of affinity for the MOR and SPR, respectively. The preservation of independent binding and activation moieties in one hybrid alkaloid/peptide molecule containing a multi-ringed alkaloid structure and a linear peptide structure, is not described in the prior art and distinguishes the present invention as novel and not evolving from prior invention.
The existence of functionally active chimeric hybrid molecules, of internally differing chemical nature, combining MOR- or SPR-activating domains linked by a novel molecular hinge are unknown to the literature of analgesia and to clinical practice. Because the MOR- and SPR-activating domains are of chemically different compositions, i.e., a multi-ringed alkaloid structure and a linear peptide structure, respectively, it is not intuitively obvious that they may be combined in a functionally active molecule.
I have achieved this by design and incorporation of a novel chemical linker-hinge region consisting of succinic acid, or gamma-hydroxy butyric acid, or d-glucuronic acid, to connect within a single molecule an alkaloid MOR-activation domain and a peptide SPR-activation domain that are modified to be compatible with that hinge. The design of novel hybrid alkaloid chimeric molecules encompassing three chemically disparate functional domains, i.e., a ringed alkaloid MOR-activation domain, a peptide SPR-activation domain, and a flexible organic acid hinge domain, is unknown to the preclinical and clinical literature of pain and analgesia.
The use of such hybrid alkaloid chimeric molecules to provide a method of novel drug delivery through selective targeting of biological tissues containing populations of MOR or SPR proteins is exemplified by, but not limited to, using chimeric hybrid molecules having an MOR binding and activation moiety and an SPR binding and activation moiety to provide analgesia which inhibiting pathological processes such as the development of opioid tolerance is unknown to the preclinical literature and clinical literature.
The chimeric multi-ringed alkaloid structure of morphine linked to the linear peptide structure of SP is illustrated in
The method employs chimeric hybrid molecules that may be designed to have a plurality of SP moieties consisting of pharmacologically ative COOH-terminal fragments of SP or a plurality of opioid akaloid moieties consisting of morphine chemically modified at its 6′hydroxyl group. The plurality of opioid moieties are each signed to bind to and activate an MOR. The plurality of SP fragments are each designed to bind to and activate an SPR.
I refer to the following amino acid sequences using the Seq. Id. Nos. below:
Nine preferred embodiments of chimeric hybrid analgesics which the method of the present invention can employ are listed in table 1.
From the description above, a number of advantages of my method of novel drug delivery through selective targeting of biological tissues containing populations of MOR or SPR proteins using chimeric hybrid molecules become evident:
Further advantages will become apparent to those skilled in the art.
Making my Invention.
The present invention can be made by a person skilled in the art, as follows: A chimeric hybrid molecule is made, comprising a moiety that activates an MOR or SPR, a moiety of the drug to be delivered that activates a PNS or CNS receptor, and a flexible linker hinge that allows contemporaneous activation of the receptors. A pharmaceutical composition of the chimeric hybrid molecule is administered to the subject, dosed to yield the desired medical benefit or treatment.
The chimeric hybrid molecules can be made by a person skilled in the art, as follows. The separate receptor-activating moieties are synthesized and purified or isolated from natural sources and then chemically cross-linked to form hybrid alkaloid/peptides chimeric molecules. All syntheses utilize well-established standard organic chemistry techniques and reagents.
For these purposes, a variety of peptide synthesis methods are common in the art, including synthesis using an automated peptide synthesizer and employing Fmoc amino acids. (Merrifield, Science 232: 241-247 (1986); Barany, et al, Intl. J. Peptide Protein Res. 30: 705-739 (1987); Kent, Ann. Rev. Biochem. 57:957-989 (1988), and Kaiser, et al, Science 243: 187-198 (1989)).
For example: SP peptide fragments are purified to over 99% chemical purity using standard peptide purification techniques such as reverse-phase high-pressure liquid chromatography (HPLC). The chemical structures of SP peptide fragments, purified by HPLC, are confirmed by mass spectroscopic analysis. SP peptide fragment moieties are synthesized prior to covalent attachment to the morphine nucleus (
For example: moieties that activate the MOR can be made using morphine that is chemically modified by covalent attachment at its 6′OH group to the hinge-forming organic molecules. Examples of hinge-forming organic molecules, as described above, include: d-glucuronic acid, succinic acid, gamma-hydroxy butyric acid.
The moieties are attached to the linker hinge. For example: chemically modified morphine derivatives, i.e., morphine-6-glucuronide, morphine-6-hemi-succinate, morphine-6-gamma-hydroxy butyrate, are covalently attached using standard condensing agents such as water soluble carbodiimide (CDI). Chemically modified SP peptide fragments, i.e., SP fragment-glucuronide, SP fragment-hemi-succinate, SP fragment-gamma-hydroxy butyrate, are covalently attached to morphine using standard condensing agents such as water soluble CDI.
Prior to pharmacological testing, the novel chimeric hybrid molecules comprising are purified to over 99% purity by standard chromatographic techniques such as reverse-phase HPLC. This represents less than about 1% chemical precursors or non-peptide chemicals in the final preparations. The chemical structures of chimeric hybrid molecules are confirmed by mass spectroscopic analysis.
Preclinically, a well-established method is used to assess the pharmacological properties of the novel chimeric hybrid compounds. Preclinical testing is conducted in conformity with governmental drug regulations. The chimeric hybrid molecules are then subjected to standard pharmacological and clinical testing for safety and efficacy.
The chimeric hybrid molecules are designed to bind to and activate populations of MORs or SPRs located primarily within the human biological tissues. The method is used to treat pain-related disorders, drug abuse, and a variety of diverse pathological disorders, with drugs that will activate MORs or SPRs and that can be functionally linked as moieties in the chimeric hybrid molecules that I invented.
Using my Invention.
My invention further provides methods of novel drug delivery through selective targeting of biological tissues containing populations of MOR or SPR proteins.
The methods use my novel chimeric hybrid molecules as novel drug delivery agents for selective targeting of biological tissues containing populations of MOR and SPR proteins. My method provides selective targeting of biological tissues containing populations of MOR proteins by administering to a living subject, i.e., a mammal (an animal class which includes humans), a novel conjugate molecule, comprised of a peptide and a non-peptide, to deliver a drug, such as Substance P, to a receptor moiety, such as the SPR, by targeting a nearby receptor site, such as the MOR, with another moiety, such as an opioid, with a novel flexible linker hinge permitting the delivered drug to activate its targeted receptor when the targeting drug activates its receptor. My method provides selective targeting of biological tissues containing populations of SPR proteins by administering to a living subject, i.e., a mammal (an animal class which includes humans), a novel conjugate molecule, comprised of a peptide and a non-peptide, to deliver a drug, such as an opioid, to a receptor moiety, such as the MOR, by targeting a nearby receptor site, such as the SPR, with another moiety, such as an SP fragment, with a novel flexible linker hinge permitting the delivered drug to activate its targeted receptor when the targeting drug activates its receptor. Through administration of the chimeric hybrid molecules, the delivered drug is targeted to its receptor via the targeting moiety of the chimeric hybrid molecule.
The invention is used by persons skilled in the art, as follows: Chimeric hybrid molecules comprising MOR- or SPR-moieties, flexible linker hinges and moieties of the drug selected for treatment of the subject's condition are manufactured and tested. Pharmaceutical compositions of the chimeric hybrid molecules are formulated to be compatible with their intended routes of administration, e.g., parenteral, intrademal, subcutaneous, injectable, intravenous, oral, intradermal, subcutaneous, transdermal (topical), transmucosal, and rectal administration. The clinically appropriate pharmaceutical compositions are administered to the subject.
Solutions or suspensions suitable for parenteral, intradermal, or subcutaneous application can include the following components: a sterile diluent such as water for injection, saline solution, fixed oils, polyethylene glycols, glycerine, propylene glycol or other synthetic solvents; antibacterial agents such as benzyl alcohol or methyl parabens; antioxidants such as ascorbic acid or sodium bisulfite; chelating agents such as ethylenediaminetetraacetic acid; buffers such as acetates, citrates or phosphates. The parenteral preparation can be enclosed in ampoules, disposable syringes or multiple dose vials made of glass or plastic.
Pharmaceutical compositions suitable for injectable use include sterile aqueous solutions or dispersions and sterile powders for the extemporaneous preparation of sterile injectable solutions or dispersion. For intravenous administration, suitable carriers include physiological saline, sterile or bacteriostatic water, or phosphate buffered saline (PBS). In all cases, the compositions must be sterile and should be fluid to the extent that they are easily injectable by syringe. Proper fluidity may be maintained by the use of a coating such as lecithin, by the maintenance of the required particle size in the case of dispersion and by the use of surfactants. Preservation of chemical and pharmaceutical integrity is achieved by various antibacterial and antifungal agents: e.g., parabens, chlorobutanol, phenol, ascorbic acid, thimerosal, etc. In many cases, it will be preferable to include isotonic agents, for example, sugars, polyalcohols such as manitol, sorbitol, sodium chloride in the composition. Prolonged absorption of the injectable compositions can be brought about by including in the composition an agent which delays absorption, for example, aluminum monostearate and gelatin.
Sterile injectable solutions can be prepared by incorporating the active compound (e.g., chimeric hybrid molecules) in the required dosage in an appropriate solvent with one or a combination of ingredients enumerated above, as required, followed by filtered sterilization.
Oral compositions generally include an inert diluent or an edible carrier. They can be enclosed in gelatin capsules or compressed into tablets. For the purpose of oral therapeutic administration, the active compound can be incorporated with binders and used in the form of tablets, troches, or capsules. Pharmaceutical binding agents, and/or adjuvant material can be included as part of the composition. The tablets, pills, capsules, troches and the like can contain any of the following ingredients, or compounds of a similar nature: a binder such as microcrystalline cellulose, gum tragacanth or gelatin; an excipient such as starch or lactose, a disintegrating agent such as alginic acid, Primogel, or corn starch; a lubricant such as magnesium stearate or Sterotes; a glidant such as colloidal silicon dioxide.
Suitable intradermal, subcutaneous, transdermal (topical), and transmucosal formulations include: gels, creams, solutions, emulsions, suspensions, carbohydrate polymers, biodegradable matrices thereof, vapors, mists, aerosols and other inhalants, and skin patches. Rectal formulations also include suppositories and enemas.
Examples of suitable pharmaceutical carriers for the various forms of administration include any of the standard pharmaceutically accepted carriers known to those of ordinary skill in the art.
Examples of pharmaceutical carriers include but are not limited to buffered saline solution, water, emulsions, various wetting agents, tablets, coated tablets and capsules. Besides an effective amount of the compounds described in the present invention, pharmaceutical compositions may include suitable diluents, preservatives, solubilizers, emulsifiers, adjuvant and/or carriers. Examples of optional ingredients which may be included in the pharmaceutical compositions of the present invention include antioxidants; low molecular weight polypeptides; proteins such as serum albumin, gelatin or immunoglobulins; amino acids such as glycine; chelating agents; sugar alcohols.
The following are examples of embodiments of my invention: In embodiments as analgesics, the method will inhibit tolerance development while being used as an analgesic dosed to provide opioid effects, due to its selective targeting capabilities and low effective dosage. In embodiments as an anti-drug abuse agents, the method will inhibit dependence formation while being used to substitute an abused drug and dosed to provide opioid effects due to its selective targeting abilities and low effective dosage. In embodiments as anti-inflammatory agents, the method will inhibit patho-physiological processes while being used to substitute an established drug and dosed to provide anti-inflammatory effects due to its selective targeting abilities and low effective dosage. In embodiments as anti-neoplastic agents, the method will inhibit patho-physiological processes while being used to substitute an established drug and dosed to provide anti-neoplastic effects due to its selective targeting abilities and low effective dosage. Other embodiments will be evident to those skilled in the art.
The reader thus will see that my invention provides a novel and useful method of drug delivery and selective targeting of biological tissues containing functionally interactive populations of protein receptors using novel chimeric hybrid molecules containing a moiety that binds to and activates the MOR or a moiety that binds to and activates the SPR. The invention can be used for a variety of clinical purposes, including pain-related analgesic indications, drug abuse intervention, and diverse pathophysiological conditions through administration of one or more embodiments of the chimeric hybrid molecules, in substitution for a traditionally administered drug to which the patient became tolerant, or on which the patient became dependent, or on which the patient became refractory or unresponsive, or to deliver a drug that activates a PNS or CNS receptor and provides pharmacological benefits to the subject.
While my description contains many specifications, these should not be construed as limitations on the scope of my invention, but rather as an exemplification of one or more of the preferred embodiments of my invention. Other variations are possible. Accordingly, the scope of my invention should be determined by the appended claims and their legal equivalents and not by the embodiments illustrated in the foregoing description.
This is a continuation-in-part of application Ser. No. 10/134,187, filed Apr. 26, 2002, as to which Applicant elected a restriction of the invention as required by an Office Action mailed on Sep. 23, 2003.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10134187 | Apr 2002 | US |
| Child | 11025494 | Dec 2004 | US |
