Patent Application
20070141009
1. Technical Field
The present disclosure relates generally to the methods and compositions for manipulating hair growth or hair loss. In particular, aspects of the present disclosure are directed to methods and compositions that interfere with genetic expression of genes involved in or related to hair loss or hair growth, for example using inhibitory nucleic acids in cases of androgenic alopecia.
2. Related Art
Hair loss in both men and women has garnered much attention from the medical and pharmaceutical industry because of the high demand for effective and reliable treatments by those suffering from this condition. In human beings, hair growth and its renewal are mainly determined by the activity of the hair follicles. Their activity is cyclical and comprises essentially three phases, namely the anagenic phase, the catagenic phase and the telogenic phase. The active anagenic phase or growth phase, which lasts several years and during which the hair grows longer, is followed by a very short and transitory catagenic or involution phase, which lasts a few weeks, and then by a resting phase, known as the telogenic phase, which lasts a few months. At the end of the resting period, the hair falls out and another cycle recommences. The head of hair is thus constantly renewed and, of the approximately 150,000 hairs, which a head of hair contains, at each instant, approximately 10% of them are at rest and will therefore be replaced in a few months.
In a significant number of cases, early hair loss takes place in subjects who are genetically predisposed to the condition. Hair loss affects men in particular and is more particularly androgenetic in character. Hair loss is also referred to as androgenic alopecia or alternatively androgeno-genetic alopecia (AGA).
Because of the link between androgens and hair loss, most hair loss therapies are designed to interfere with androgenic action or to include some form of hormone therapy. Although therapies for hair loss do exist, these therapies are not effective in many individuals, and in some cases are only available to specific genders of suffers.
For example, U.S. Pat. Nos. 5,571,817; 5,670,643 and 6,124,362 disclose a composition and method for producing and using 17β-N-t butylcarbamoyl4-aza-5α-androst-1-en-3-one known generically as finesteride. The efficacy of compounds such as finesteride relies upon their ability to inhibit the action of various proteins involved in androgen mediated hair loss. Finesteride is commercially disturbed under the tradename Propecia® and is a testosterone-5α-reductase inhibitor. 5α-reductase is an enzyme that coverts testosterone into dihydroxy testosterone (DHT). Thus, finesteride decreases the amount of DHT. Finesteride is reported to be less effective in women and may potentially cause serious birth defects if used by pregnant women.
Another well known treatment for hair loss uses a compound known as minoxidil. U.S. Pat. No. 4,596,812 discloses methods of using minoxidil, 6-amino-1,2-dihydro-1-hydroxy-2-imino-4-piperodinopyrimidine, for treating male pattern baldness. Minoxidil is a vasodilator developed for the treatment of high blood pressure. Minoxidil is believed to increase hair growth by increasing the delivery of blood to a desired area. It is generally recognized that not all individuals will respond to minoxidil, and those who do respond require treatment application for life to maintain efficacy. Additionally, minoxidil may cause itchiness and redness of the scalp.
Thus, there is a need for new and effective treatments for androgen related disorders, including hair loss, for both men and women.
There is also a need for new and effective compositions for the treatment of hair loss including the prevention of hair loss or the induction of hair growth.
Aspects of the present disclosure are directed to compositions and methods for the use of inhibitory nucleic acids, for example small inhibitory ribonucleic acids (siRNA), to adjust, manipulate, prevent, inhibit, interfere, or block the androgen signal transduction pathway in a host cell, for example in a host's hair cell. Other aspects of the disclosure provide compositions and methods for interfering with the androgen signal transduction pathway by down regulating the expression of proteins involved in the androgen signal transduction pathway. Exemplary gene targets encoding proteins involved in the androgen signal transduction pathway include but are not limited to isozymes I and II of 5-α reductase, the androgen receptor, aromatase, 3-α-hydroxysteroiddehydrogenase, 3-β-hydroxysteroiddehydrogenase , 3-β-hydroxysteroiddehydrogenase-4-5-isomerase, 17-β-hydroxysteroidoxidoreductase, and steroid sulfatase. In some aspects, the inhibitory nucleic acids, for example siRNAs, interfere with the expression of targeted genes by preventing, reducing, or inhibiting the translation of mRNA transcribed from the targeted gene.
Another aspect of the disclosure provides compositions and methods for the treatment of androgen related diseases by decreasing the sensitivity of androgens in a host or host cell. The sensitivity of a cell to androgens can be reduced or regulated using siRNAs that interfere with or interrupt the androgen signal transduction pathway, for example by interfering or blocking the expression or function of any protein in the androgen signal transduction cascade. An exemplary aspect provides methods and compositions for treating hair loss using siRNAs, for example, to regulate the cell cycle of hair cells by manipulating the androgen signal transduction pathway.
Still another aspect or the disclosure provides compositions and methods for treating hair loss in a mammal, for example a human, by interfering with or inhibiting, the androgen signal transduction pathway of a hair cell. For example, siRNAs can be used to inhibit or reduce the production of DHT in a host or host cell using siRNAs targeted to enzymes involved in the production of DHT, for example 5-α reductase. Contacting mRNAs encoding 5α-reductase with a corresponding siRNA interferes with the translation of the mRNA and thereby interferes with the expression of the 5α-reductase. Some aspects provide siRNAs that induce the degradation, typically enzymatic degradation, of the target mRNA. The less 5α-reductase, the less DHT or ability to produce DHT. By reducing or inhibiting the production of DHT, the cycle of hair growth and renewal can be manipulated resulting in reduced hair loss or promoting new hair growth. Accordingly, other aspects of the present disclosure are directed to compositions and methods that inhibit the production of proteins that mediate the effects of androgens in androgenetic alopecia. Exemplary proteins included those proteins encoded by the genes for both isozymes I and II of 5-α reductase, the androgen receptor, aromatase, 3-α-hydroxysteroiddehydrogenase, 3-β-hydroxysteroiddehydrogenase,3-β-hydroxysteroiddehydrogenase-4-5-isomerase, 17-β-hydroxysteroidoxidoreductase, and steroid sulfatase.
Still other aspects of the disclosure provide compositions and methods for manipulating the androgen receptor signal transduction pathway in a host cell to reduce, inhibit, or prevent hair loss or to induce hair growth. In one aspect, inhibitory nucleic acids, typically ribonucleic acids, and more typically double stranded ribonucleic acids are provided that interfere with, inhibit, or interrupt the expression of proteins involved in the androgen signal transduction pathway. In particular, inhibitory ribonucleic acids (iRNA) or small inhibitory ribonucleic acids (siRNA) that comprise at least a partial sequence of nucleic acids encoding proteins involved with or related to the androgen signal transduction pathway are disclosed that inhibit or interfere with the expression of these proteins. The active siRNAs can be from about 10 to about 25 nucleotides in length although it will be appreciated that longer RNAs can be employed that are processed to result in siRNAs of smaller sizes, typically from about 10 to about 25 nucleotides in length.
Accordingly, aspects of the present discisoure describe a method of treating the hyperandrogenic conditions of androgenic alopecia, including male pattern alopecia, acne vulgaris, seborrhea, and female hirsutism by topical administration, and a method of treating all of the above conditions as well as benign prostatic hypertrophy, by systemic administration, of the novel compounds of the present disclosure. In one method, an siRNA is administered to a host, wherein the siRNA interrupts or interferes with the expression of a gene involved in the androgen signal transduction pathway that results in the reduction or inhibition of DHT production or androgen receptor expression.
Still another aspect provides a method of screening siRNAs to identify siRNAs that inhibit, interfere or otherwise disrupt the androgen signal transduction pathway, for example in hair cells. The screening can be accomplished using in vitro cell lines. Alternatively, the screening method can be used to identify compounds that mimic or synergize with siRNAs.
Yet another aspect provides a vector, typically a viral vector, that encodes a siRNA that interferes with or inhibits the androgen signal transduction pathway. The vector can be designed to express double stranded siRNA directly or indirectly wherein the siRNA comprises at least a portion of the target mRNA nucleic acid sequence, typically a mRNA encoding a protein in the androgen signal transduction pathway. Alternatively, the vector can encode a nucleic acid sequence containing specific cleavage sites such that the vector expresses a nucleic acid that can be cleaved to produce inhibitory nucleic acids of less than about 30 nucleotides in length. The expressed inhibitory nucleic acids are typically RNA, and more typically are double-stranded RNA. An exemplary vector includes a promoter for human RNA polymerase III, flanked on the 3′ end by a termination signal composed of five T residues. Between start and stop signals is a 21-nucleotide DNA template and its inverted repeat separated by a short non-homologous nucleotide spacer.
The present disclosure also encompasses a cell comprising a siRNA targeted to a mRNA encoding a protein in the androgen signal transduction pathway, for example isozymes I and II of 5-α reductase, the androgen receptor, aromatase, 3-α-hydroxysteroiddehydrogenase, 3-β-hydroxysteroiddehydrogenase, 3-β-hydroxysteroiddehydrogenase-4-5-isomerase, 17-β-hydroxysteroidoxidoreductase, and steroid sulfatase. Alternatively, the cell comprises a vector that when expressed, produces a siRNA that interferes with or inhibits the expression of a protein in the androgen signal transduction pathway. Suitable vectors containing functional elements such as promoters and other regulatory elements are known in the art. The sequence of representative siRNAs is provided in Table 1.
The inhibitory nucleic acids of the present disclosure can be formulated for administration by conventional means including topical, oral, and intravenous administration. These topical pharmaceutical compositions containing the compounds of the present disclosure ordinarily include about 0.1% to 15%, preferably about 0.1 to 5%, and more preferably about 0.1% to 2%, of the active compound, in admixture with a pharmaceutically acceptable carrier.
The compositions according to the disclosure may be in any form suitable for application to hair and scalp, especially in the form of an aqueous, alcoholic or aqueous-alcoholic preparation, such as a solution, gel, cream, emulsion or dispersion.
FIGS. 5A-C are fluorescence micrographs of Sy5y cells transfected to express with GFP-tagged steroid 5-alpha-reductase and rhodamine labelled dsRNA specific for the reporter protein.
Definitions
Unless otherwise indicated the following terms used in the specification and claims have the meanings discussed below:
The term “organism” refers to any living entity comprised of at least one cell. A living organism can be as simple as, for example, a single eukaryotic cell or as complex as a mammal, including a human being.
The term “therapeutically effective amount” as used herein refers to that amount of the compound being administered which will relieve to some extent one or more of the symptoms of the disorder being treated. In reference to hair loss, a therapeutically effective amount refers to that amount which has the effect of (1) reducing the amount of hair loss, (2) inhibiting (that is, slowing to some extent, preferably stopping) androgen sensitivity, (3) inducing the grow of hair, and/or, (4) relieving to some extent (or, preferably, eliminating) one or more symptoms associated with the androgen related disease including but not limited to hair loss.
“Pharmaceutically acceptable salt” refers to those salts which retain the biological effectiveness and properties of the free bases and which are obtained by reaction with inorganic or organic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, methanesulfonic acid, ethanesulfonic acid, p-toluenesulfonic acid, salicylic acid, malic acid, maleic acid, succinic acid, tartaric acid, citric acid, and the like.
A “pharmaceutical composition” refers to a mixture of one or more of the compounds described herein, or a pharmaceutically acceptable salts thereof, with other chemical components, such as physiologically acceptable carriers and excipients. The purpose of a pharmaceutical composition is to facilitate administration of a compound to an organism.
As used herein, a “pharmaceutically acceptable carrier” refers to a carrier or diluent that does not cause significant irritation to an organism and does not abrogate the biological activity and properties of the administered compound.
An “excipient” refers to an inert substance added to a pharmaceutical composition to further facilitate administration of a compound. Examples, without limitation, of excipients include calcium carbonate, calcium phosphate, various sugars and types of starch, cellulose derivatives, gelatin, vegetable oils and polyethylene glycols.
“Treating” or “treatment” of a disease includes preventing the disease from occurring in an animal that may be predisposed to the disease but does not yet experience or exhibit symptoms of the disease (prophylactic treatment), inhibiting the disease (slowing or arresting its development), providing relief from the symptoms or side-effects of the disease (including palliative treatment), and relieving the disease (causing regression of the disease). With regard to cancer, these terms simply mean that the life expectancy of an individual affected with a cancer will be increased or that one or more of the symptoms of the disease will be reduced.
The term “prodrug” refers to an agent, including nucleic acids and proteins, which is converted into a biologically active form in vivo. Prodrugs are often useful because, in some situations, they may be easier to administer than the parent compound. They may, for instance, be bioavailable by oral administration whereas the parent compound is not. The prodrug may also have improved solubility in pharmaceutical compositions over the parent drug. A prodrug may be converted into the parent drug by various mechanisms, including enzymatic processes and metabolic hydrolysis. Harper, N.J. (1962). Drug Latentiation in Jucker, ed. Progress in Drug Research, 4:221-294; Morozowich et al. (1977). Application of Physical Organic Principles to Prodrug Design in E. B. Roche ed. Design of Biopharmaceutical Properties through Prodrugs and Analogs, APhA; Acad. Pharm. Sci.; E. B. Roche, ed. (1977). Bioreversible Carriers in Drug in Drug Design, Theory and Application, APhA; H. Bundgaard, ed. (1985) Design of Prodrugs, Elsevier; Wang et al. (1999) Prodrug approaches to the improved delivery of peptide drug, Curr. Pharm. Design. 5(4):265-287; Pauletti et al. (1997). Improvement in peptide bioavailability: Peptidomimetics and Prodrug Strategies, Adv. Drug. Delivery Rev. 27:235-256; Mizen et al. (1998). The Use of Esters as Prodrugs for Oral Delivery of β-Lactam antibiotics, Pharm. Biotech. 11:345-365; Gaignault et al. (1996). Designing Prodrugs and Bioprecursors I. Carrier Prodrugs, Pract. Med. Chem. 671-696; M. Asgharnejad (2000). Improving Oral Drug Transport Via Prodrugs, in G. L. Amidon, P. I. Lee and E. M. Topp, Eds., Transport Processes in Pharmaceutical Systems, Marcell Dekker, p. 185-218; Balant et al. (1990) Prodrugs for the improvement of drug absorption via different routes of administration, Eur. J. Drug Metab. Pharnmacokinet., 15(2): 143-53; Balimane and Sinko (1999). Involvement of multiple transporters in the oral absorption of nucleoside analogues, Adv. Drug Deliveiy Rev., 39(1-3):183-209; Browne (1997). Fosphenytoin (Cerebyx), Clin. Neuropharmacol. 20(1): 1-12; Bundgaard (1979). Bioreversible derivatization of drugs—principle and applicability to improve the therapeutic effects of drugs, Arch. Pharm. Chemi. 86(1): 1-39; H. Bundgaard, ed. (1985) Design of Prodrugs, New York: Elsevier; Fleisher et al. (1996). Improved oral drug delivery: solubility limitations overcome by the use of prodrugs, Adv. Drug Deliveiy Rev. 19(2): 115-130; Fleisher et al. (1985). Design of prodrugs for improved gastrointestinal absorption by intestinal enzyme targeting, Methods Enzymol. 112: 360-81; Farquhar D, et al. (1983). Biologically Reversible Phosphate-Protective Groups, J. Pharm. Sci., 72(3): 324-325; Han, H. K. et al. (2000). Targeted prodrug design to optimize drug delivery, AAPS PharmSci., 2(1): E6; Sadzuka Y. (2000). Effective prodrug liposome and conversion to active metabolite, Cur.r Drug Metab., 1(1):31-48; D. M. Lambert (2000) Rationale and applications of lipids as prodrug carriers, Eur. J. Pharm. Sci., 11 Suppl 2:S15-27; Wang, W. et al. (1999) Prodrug approaches to the improved delivery of peptide drugs. Curr. Pharm. Des., 5(4):265-87.
As used herein, the term “topically active agents” refers to compositions of the present disclosure that elicit pharmacological responses at the site of application (contact) to a host
As used herein, the term “topically” refers to application of the compositions of the present disclosure to the surface of the skin and mucosal cells and tissues.
As used herein, the term “surface” is used in its broadest sense. In one sense, the term refers to the outermost boundaries of an organism or inanimate object (e.g., vehicles, buildings, and food processing equipment, etc.) that are capable of being contacted by the compositions of the present disclosure (e.g., for animals: the skin, hair, and fur, etc., and for plants: the leaves, stems, flowering parts, and fruiting bodies, etc.). In another sense, the term also refers to the inner membranes and surfaces of animals and plants (e.g., for animals: the digestive-tract, vascular tissues, and the like, and for plants: the vascular tissues, etc.) capable of being contacted by compositions by any of a number of transdermal delivery routes (e.g., injection, ingestion, transdermal delivery, inhalation, and the like).
Androgen signal transduction pathway means the physiological and or biological sequence of events and the proteins and genes involved therein, from the production of androgen through the binding to the androgen receptor and the subsequent binding and activation of the androgen receptor and associated proteins and cofactors resulting in the induction of gene transcription.
The term “nucleic acid” is a term of art that refers to a string of at least two base-sugar-phosphate combinations. For naked DNA delivery, a polynucleotide contains more than 120 monomeric units since it must be distinguished from an oligonucleotide. However, for purposes of delivering RNA, RNAi and siRNA, either single or double stranded, a polynucleotide contains 2 or more monomeric units. Nucleotides are the monomeric units of nucleic acid polymers. The term includes deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) in the form of a messenger RNA, anti-sense, plasmid DNA, parts of a plasmid DNA or genetic material derived from a virus. Anti-sense is a polynucleotide that interferes with the function of DNA and/or RNA. The term nucleic acids—refers to a string of at least two base-sugar-phosphate combinations. Natural nucleic acids have a phosphate backbone, artificial nucleic acids may contain other types of backbones, but contain the same bases. Nucleotides are the monomeric units of nucleic acid polymers. The term includes deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). RNA may be in the form of an tRNA (transfer RNA), snRNA (small nuclear RNA), rRNA (ribosomal RNA), mRNA (messenger RNA), anti-sense RNA, RNAi, siRNA, and ribozymes. The term also includes PNAs (peptide nucleic acids), phosphorothioates, and other variants of the phosphate backbone of native nucleic acids.
The term “siRNA” means a small inhibitory ribonucleic acid. The siRNA are typically less than 30 nucleotides in length and can be single or double stranded. The ribonucleotides can be natural or artificial and can be chemically modified. Longer siRNAs can comprise cleavage sites that can be enzymatically or chemically cleaved to produce siRNAs having lengths less than 30 nucleotides, typically 21 to 23 nucleotides. siRNAs share sequence homology with corresponding target mRNAs. The sequence homology can be 100 percent or less but sufficient to result is sequence specific association between the siRNA and the targeted mRNA. Exemplary siRNAs do not activate the interferon signal transduction pathway.
The term “inhibitory nucleic acid” means an RNA, DNA, or combination thereof that interferes or interrupts the translation of mRNA. Inhibitory nucleic acids can be single or double stranded. The nucleotides of the inhibitory nucleic acid can be chemically modified, natural or artificial.
Embodiments of present disclosure are directed, in part, to preventing, reducing, or inhibiting hair loss in a host, for example a mammal, using compositions comprising inhibitory nucleic acids such as siRNAs or salts or prodrugs thereof. The siRNAs of the present disclosure are designed to inhibit or interfere with the translation of mRNA encoding proteins involved in the androgen signal transduction pathway. In some aspects, the siRNAs induce the enzymatic cleavage of target mRNAs. Proteins involved in the androgen signal transduction pathway include but are not limited to: the androgen receptor, 5-α reductase, aromatase, 3-α-hydroxysteroiddehydrogenase, 3-β-hydroxysteroiddehydrogenase, 3-β-hydroxysteroiddehydrogenase-4-5-isomerase, 17-β-hydroxysteroidoxidoreductase, and steroid sulfatase. Alternatively, aspects of the disclosure is also directed to inducing or increasing the growth of hair, for example using compositions comprising inhibitory nucleic acids such as siRNAs. The sequence of exemplary siRNAs and their targets is provided in Table 1.
In one embodiment, the expression of androgen receptor in a host cell, typically a hair cell, is reduced or inhibited by contacting the hair cell with an siRNA. siRNAs of the present disclosure comprise at least a partial sequence of the target mRNAs, for example mRNA encoding the androgen receptor. The sequence homology between an siRNA and a target mRNA can be 100 percent or less but greater than about 50 percent, and typically 90 percent or greater. The percentage of sequence homology between siRNA and a target mRNA should be sufficient to result in sequence specific association between the siRNA and the target mRNA under cytoplasmic conditions.
One exemplary embodiment of the present disclosure is directed to the treatment or prevention of androgen related hair loss in an organism, for example the treatment or prevention of alopecia using inhibitory nucleic acids to interfere or interrupt the androgen receptor signal transduction pathway. Alopecia is essentially due to a disturbance in hair renewal which results, at first, in an acceleration in the frequency of the cycles at the expense of the quality of the hair and then of its amount. A progressive thinning of the head of hair takes place by regression of the so-called “terminal” hairs to the downy stage. Regions are preferentially affected, in particular the temple or frontal bulbs in men and, in women, a diff-use alopecia of the vertex is observed. The term alopecia covers a whole family of complaints of the hair follicle, whose final consequence is the partial or general permanent loss of the hair.
Accordingly, the present disclosure encompasses the treatment of hair loss in men and women related including alopecia, pattern baldness, or androgen related hair loss. In one embodiment, inhibitory nucleic acids prevent hair loss by down-regulating, inhibiting, or interrupting the expression of the androgen receptor in a host cell, for example a hair cell. By down-regulating the androgen receptor in hair cells, the hair cells are desensitized to androgens and the cell cycle of the hair cell is unaffected by androgens. Thus, another embodiment of the present disclosure provides a hair cell desensitized to androgens by inhibitory nucleic acids, for example siRNAs homologous to the androgen receptor that inhibit or reduce the expression of the androgen receptor in a host hair cell. It will be appreciated by those of skill in the art that the present disclosure encompasses siRNAs designed to interrupt or interfere with the expression or function of any protein in the androgen signal transduction pathway, either directly or indirectly, for the treatment, prevention, or reduction of hair loss in an organism.
The inhibitory nucleic acids of certain embodiments of the present disclosure are directed to inhibiting or interfering with the expression of proteins involved in the androgen signal transduction pathway. The inhibitory nucleic acids disclosed herein include small inhibitory ribonucleic acids (siRNAs) that are typically less than 30 nucleotides in length, more typically 21 to 23 nucleotides in length, and can be single or double stranded. One strand of a double-stranded siRNA comprises at least a partial sequence complementary to a target mRNA. The ribonucleotides of the siRNA can be natural or artificial and can be chemically modified. Longer siRNAs can comprise cleavage sites that can be enzymatically or chemically cleaved to produce siRNAs having lengths less than 30 nucleotides. siRNAs share sequence homology with corresponding target mRNAs. The phosphate backbones of the siRNAs can be chemically modified to resist enzymatic degradation. The sequence homology can be about 100 percent or less, but sufficient to result is sequence specific association between the siRNA and the targeted mRNA.
Nucleic acids, in particular RNA, are known to participate in a form of post-transcriptional gene silencing termed “RNA interference” or RNAi. First observed in plants, reduction of expression of specific mRNA sequences was found to be inducible in Drosophila melanogaster and Caenorhabditis elegans by introduction of double-stranded RNA (dsRNA) molecules mimicking the sequence of the mRNA. The effect was found to be potent and extremely long-lived in these experimental model organisms, generally extending to the F1 progeny of a treated adult specimen. Additionally, the effect was found to be exquisitely sequence-specific; discrepancy of even a few base pairs between the dsRNA and the target mRNA virtually abolished the silencing. RNAi has been used experimentally in these non-mammalian systems to generate transient silencing of specific genes of interest, especially those which are not amenable to more traditional gene knockout methods (e.g., those that produce embryonic lethality and thus cannot be studied in the adult animal).
The first evidence that dsRNA could lead to gene silencing came from work in the nematode Caenorhabditis elegans. Researchers Guo and Kemphues used antisense RNA to shut down expression of the par-1 gene in order to assess its function. As expected, injection of the antisense RNA disrupted expression of par-1, but quizzically, injection of the sense-strand control did too. This result was a puzzle until three years later. It was then that Fire and Mello first injected dsRNA—a mixture of both sense and antisense strands—into C. elegans. This injection resulted in much more efficient silencing than injection of either the sense or the antisense strands alone. Injection of just a few molecules of dsRNA per cell was sufficient to completely silence the homologous gene's expression. Furthermore, injection of dsRNA into the gut of the worm caused gene silencing not only throughout the worm, but also in its first generation offspring. The potency of RNAi inspired Fire and Timmons to try feeding nematodes bacteria that had been engineered to express dsRNA homologous to the C. elegans unc-22 gene. Surprisingly, these worms developed an unc-22 null-like phenotype. Further work showed that soaking worms in dsRNA was also able to induce silencing. These strategies, whereby large numbers of nematodes are exposed to dsRNA, have enabled large-scale screens to select for RNAi-defective C. elegans mutants and have led to large numbers of gene knockout studies within this organism. Thus, one embodiment of the present disclosure provides siRNAs comprising a sense strand and an anti-sense strand, wherein the sense strand comprises at least a partial sequence of a target mRNA.
RNAi has also been observed in Drosophila melanogaster. Although a strategy in which yeast were engineered to produce dsRNA and then fed to fruit flies failed to work, microinjecting Drosophila embryos with dsRNA does induce silencing. Silencing can also be induced by biolistic techniques in which dsRNA is “shot” into Drosophila embryos, or by engineering flies to carry DNA containing an inverted repeat of the gene to be silenced. Over the last few years, these RNAi strategies have been used as reverse genetics tools in Drosophila organisms, embryo lysates, and cells to characterize various loss-of-function phenotypes. Zamore and colleagues found that dsRNA added to Drosophila embryo lysates was processed to 21-23 nucleotide species. They also found that the homologous endogenous mRNA was cleaved only in the region corresponding to the introduced dsRNA and that cleavage occurred at 21-23 nucleotide intervals.
Current models of RNAi divide the process of inhibition into broad “initiation” and “effector” stages. In the initiation step, input dsRNA is digested into 21-23 nucleotide small interfering RNAs (siRNAs), which have also been called “guide RNAs.” Evidence indicates that siRNAs are produced when the enzyme Dicer, a member of the RNase III family of dsRNA-specific ribonucleases, processively cleaves dsRNA in an ATP-dependent, processive manner. Successive cleavage events degrade the RNA to 19-21 bp duplexes (siRNAs), each with 2-nucleotide 3′ overhangs. Inhibitory nucleic acids of the present disclosure can be enzymatically cleaved, for example in vivo, to produce siRNAs from 10 to about 30 nucleotides, typically about 19 to about 23 nucleotides.
In the effector step, the siRNA duplexes bind to a nuclease complex to form what is known as the RNA-induced silencing complex, or RISC. An ATP-depending unwinding of the siRNA duplex is required for activation of the RISC. The active RISC then targets the homologous transcript by base pairing interactions and cleaves the mRNA˜12 nucleotides from the 3′ terminus of the siRNA. Although the mechanism of cleavage is at this date unclear, research indicates that each RISC contains a single siRNA and an RNase that appears to be distinct from Dicer. Because of the remarkable potency of RNAi in some organisms, an amplification step within the RNAi pathway has also been proposed. Amplification could occur by copying of the input dsRNAs, which would generate more siRNAs, or by replication of the siRNAs themselves. Alternatively or in addition, amplification could be effected by multiple turnover events of the RISC. One embodiment encompasses the in vivo amplification of the siRNAs disclosed herein. Additionally, the siRNAs described herein can form a complex with additional proteins and/or cofactors to enzymatically cleave a target mRNA.
Androgens, specifically testosterone (T) and dihydroxytestosterone (DHT), mediate hair loss including AGA. The present disclosure provides siRNAs that inhibit the expression of androgen receptors or 5α0 reductase thereby preventing or reducing hair loss or stimulating hair growth. Testosterone taken up by hair cells in the scalp is converted to DHT by the enzyme 5-α reductase. Inhibiting the expression of 5α reductase with the siRNAs of the present disclosure reduces the levels of DHT. In one embodiment, DHT can be reduced locally or systemically using the inhibitory nucleic acids described herein.
DHT binds to its receptor, the Androgen Receptor (AR), which acts to alter nuclear gene expression. The AR is an intracellular receptor residing in the nucleus or cytoplasm and is a member of the steroid hormone receptor family. The change in nuclear gene expression of androgen responsive genes in response to androgen forces the hair cell to progressively shorten the duration of anagen with successive hair cycles, causing reduced hair renewal and hair loss.
The AR is typically bound to heat shock protein 90 that maintains the AR inactive state and the AR hormone binding affinity (Fang, Y. et al. (1996). J Biol Chem. 271 (45), 28697-28702). Upon binding however, direct androgen action is initiated as inhibitory heat shock proteins are released from the androgen receptor. The AR is then phosphorylated and undergoes a conformational change necessary for translocation and dimerization (Grino, P. B. et al. (1987). Endocrinol. 120, 1914-1920). Although in the wild-type receptor, this ligand binding is necessary for transcriptional activity, one in vivo receptor with a deleted ligand binding domain does possess transcriptional activity. This may indicate that the unliganded binding domain is actually a repressor of receptor action due to conformational constraints in the unbound receptor possessing the ligand binding domain (Jenster, G. et al. Mol Endocrinol. (1991). 5, 1396-1404).
Once in the nucleus (either by direct binding there or by translocation), the phosphorylated receptor is dimerized and binds to a DNA androgen response element (ARE). The hormone response element, which is also bound by other hormone receptors from this family, is a 15 base pair sequence responsible for transcription initiation. Once bound, other transcription regulating proteins or co-activators may also bind the AR-ARE complex to stabilize the promoter of the regulated gene (Shibata, H. (1997). Recent Progress Horm Research. 52, 141-164; Kang, H. Y. (1999). J. Biol. Chem. 274 (13), 8570-8576). Such co-activators include proteins such as ARA 54, ARA 55, ARA 70, ARA 160 (Yeh, S. et al. (1996). Proc. Natl. Acad. Sci. USA. 93 (11), 5517-5521; Hsiao, P. W. (1999). J. Biol. Chem. 32, 22373-22379). This binding of such co-factors ultimately results in the regulation of transcription rate. Thus, one embodiment provides inhibitory nucleic acids, for example siRNAs, comprising at least a partial sequence of a target mRNA encoding a protein that associates with the androgen receptor, for example the AR-ARE. These siRNAs can inhibit or interfere with the expression of the AR associated proteins and thereby inhibit or interfere with the transcription acitivity of the AR. Exemplary AR associated proteins include but are not limited to ARA 54, ARA 55, ARA 70, ARA 160. The resultant mRNA from androgen dependent transcription is then processed and transported to ribosomes where it is translated into proteins that can alter cellular function. Thus, exemplary embodiments of the present disclosure encompass siRNAs that inhibit or interfere with the translation of mRNA from androgen dependent transcription.
In some tissues there is evidence for a ligand-independent dependent activation of transcriptional activity via the AR. An unliganded receptor with a deletion of the ligand binding domain may possess activity. This indicates activity in the absence of ligand binding. In addition, growth factors (insulin-like growth factor, keratinocyte growth factor, and epidermial growth factor) as well as protein kinase A activators might be able to induce a transcriptionally active AR in the absence of ligand binding. Some of these ligand independent transcription activators may act via influencing the AR phosphorylation state. Thus, one embodiment discloses siRNAs targeted to ligand independent transcription activators of AR, for example growth factors and protein kinas A activators for the treatment of androgen related diseases such as hair loss.
Ligand binding, for example DHT, alters the protein conformation of the AR to allow binding of coactivator molecules that can amplify the hormone signal and mediate transcriptional initiation of androgen responsive genes. The AR can also undergo intramolecular interactions that influence its activity and interaction with cofactors. The AR protein has several domains or motifs similar to the modular structure of other steroid hormone receptors. There are two characterized forms of the androgen receptor. The first, and predominant form, is a 110-114 kDa protein of 910-919 amino acids. The second is a smaller 87 kDa protein of about 720-729 amino acids in length that makes up only about 4-26% of the detectible androgen receptors located in varying tissues.
Exemplary siRNAs of the present disclosure can also be targeted to enzymes that mediate the production or modification of androgens, for ezample 5-α reductase. The enzyme 5-α reductase converts testosterone into DHT and it is DHT that is most potent in promoting AGA. There are at least two 5-α reductase isoenzymes, type I and type II. They are active in different regions of the body, but they both produce DHT that can circulate throughout the body and exert effects in organs other than where DHT was produced. Type II 5-α reductase is the most active enzyme form. It produces 60% to 70% of the total DHT human beings. Type I produces the remaining 30% to 40% of DHT. 5-α reductase inhibitors, promoted as treatments for AGA, should ideally block both types of isoenzyme to have maximum effect. Finasteride is a type II 5-α reductase inhibitor and so reduces DHT levels by at most 70%. However, the use of finesteride has been associated with reduced libido, teratagenic effects and other side effects in certain individuals thus prompting a more specific and safer approach to treating AGA.
Existing Therapies
All androgen-responsive genes are activated by androgen receptor (AR) bound to either T or DHT and it is believed that AR is more transcriptionally active when bound to DHT than T. Thus, therapies for treating androgen related diseases, including alopecia, encompass anti-androgens. The present disclosure encompasses therapies for hair loss, in particular androgen related hair loss, by using the inhibitory nucleic acids disclosed herein, alone, or in combination with existing hair loss therapies. For example the two classes of anti-androgens, presently available, are the steroidal derivatives, all of which possess mixed agonistic and antagonistic activities, and the pure non-steroidal anti-androgens of the class of flutamide and its derivatives. Flutamide has a structure similar to the male sex hormone testosterone. It works by blocking and preventing the binding of testosterone to the receptors on the surface of cells. The non-steroidal flutamide and its derivatives display pure anti-androgenic activity, without exerting agonistic or any other hormonal activity. Flutamide and its derivatives, Casodex and Anandron, are highly effective in the treatment of prostate cancer.
Exemplary anti-androgens with a steroid structure include but are not limited to (17 alpha-acetoxy-6-chloro-2-oxa-4,6-pregnadiene-3,20-dione). This compound inhibits 5-αdihydrotestosterone (5-α-DHT) and testosterone receptors activity by blocking androgen receptors and in this way decreasing the nuclear androgen receptors fraction. Representative examples of steroidal blocking agents include spironolactone, cyproterone acetate, trimethyltrienolone (available from Roussel Uclaf under the designation RU 2956), canrenone and canrenoic acid. Examples of suitable non-steroidal blocking agents include flutamide (α,α,.α.-trifluoro-2-methyl-4′-nitro-m-propionotoluidide) and hydroxy-flutamide (α,α,.α.-trifluoro-2-methyl-4′-nitro-m-lactoluidide), both available from Schering Corp., and RU 23908 (5,5-dimethyl-3-[4-nitro-3(trifluoromethyl)phenyl]-2,4-imidazolidinedione) and RU 22930 (5,6-dihydro-2-methyl-4-[4-nitro-3-(trifluromethyl)phenyl]-2H-1,2,4-oxadio zin-3-(4H)-one), available from Roussel Uclaf.
RU 56187 and RU 58841 are additional examples of non-steroidal anti-androgens. They are N-substituted arylthiohydantoins and inhibit 5 α-dihydrotestosterone (5-α-DHT) and testosterone receptors activity by blocking androgen receptors. RU 58841 and RU 56187 are eliminated from blood stream relatively quickly, but they form a common metabolite, the N-desalkyl derivative, RU 56279 (also anti-androgen), which is eliminated much more slowly and is responsible for general adverse anti-androgenic effects.
Other compounds for the treatment of hair loss are disclosed in U.S. Pat. No. 6,451,777 which is incorporated by reference in its entirety and include but are not limited to lupane triterpenes, derivatives of lupane triterpenes, derivatives of oleanane triterpenes, derivatives of ursane triterpenes, and salts and mixtures thereof.
Additional therapeutic agents for the treatment of hair loss can be used in combination with the present disclosure, including formulations in which a minoxidil solution, typically comprising about 5% minoxidil, is combined with azelaic acid, typically about 5%. Azelaic acid is a topically effective inhibitor of 5-α reductase. Another part of this formulation is the anti-inflammatory agent betamethasone valerate. Additionally, retinoic acid can be added, typically about 0.025%.
Spironolactone is another suitable second therapeutic agent for use with the present disclosure. Spironolactone is a medication that has been used for many years to treat hypertension and fluid retention. Its effect is local at blocking DHT and there are no systemic effects from its use on the scalp. Spironolactone is a potent anti-androgen. It competes with DHT for the receptor sites on the hair follicles
According to another aspect of the present disclosure, a method is provided for hormonal therapy in a patient (i.e., suffering from an androgen-dependent condition) which includes contacting a nucleic acid encoding an 5-α reductase of a patient with an inhibitory RNA under conditions effective to bind the inhibitory RNA compound to the nucleic acid encoding an 5-α reductase and effect a change in an androgen-dependent condition, such as alopecia. Androgen-dependent conditions which may be treated according to the present disclosure include those conditions which are associated hyperandrogenic conditions.
Exemplary embodiments of the present disclosure include pharmaceutical compositions that can be manufactured by processes well known in the art, e.g., by means of conventional mixing, dissolving, granulating, dragee-making, levigating, emulsifying, encapsulating, entrapping, lyophilizing processes or spray drying. Moreover, in certain embodiments, the compositions of the present disclosure may be formulated for horticultural or agricultural use. Such formulations include dips, sprays, seed dressings, stem injections, sprays, and mists.
The compositions of the present disclosure can be liquids or lyophilized or otherwise dried formulations and include diluents of various buffer content (e.g., Tris-HCl, acetate, phosphate), pH and ionic strength, additives such as albumin or gelatin to prevent absorption to surfaces, a surfactant such as a polysorbate surfactant (e.g., TWEEN 20, TWEEN 40, TWEEN 60, and TWEEN 80), a pheoxypolyethoxyethanol surfactant (e.g., TRITON X-100, X-301, X-165, X-102, and X-200, and TYLOXAPOL) Pluronic F68, or sodium dodecyl sulfate, solubilizing agents (e.g., glycerol, polyethylene glycerol), anti-oxidants (e.g., ascorbic acid, sodium metabisulfite), preservatives (e.g., Thimerosal, benzyl alcohol, parabens), bulking substances or tonicity modifiers (e.g., lactose, mannitol), covalent attachment of polymers such as polyethylene glycol to the protein, complexation with metal ions, or incorporation of the material into or onto particulate preparations of polymeric compounds such as polylactic acid, polglycolic acid, hydrogels, etc, or onto liposomes, microemulsions, micelles, unilamellar or multilamellar vesicles, erythrocyte ghosts, or spheroplasts. Such compositions will influence the physical state, solubility, stability, rate of in vivo release, and rate of in vivo clearance, controlled or sustained release compositions include formulation in lipophilic depots (e.g., fatty acids, waxes, oils).
The present disclosure contemplates formulations that may be employed in pharmaceutical and therapeutic compositions and applications suitable for inhibiting the action of androgens relating to hair loss. Such compositions may be employed to inhibit expression of proteins related to hair growth or loss, interfere with signal transduction mechanisms of the androgen receptor, interfere with the formation, dissemination of androgens, or increase the growth of hair.
For in vivo applications, the compositions can be administered in any effective pharmaceutically acceptable form to warm blooded animals having hair, including human and animal subjects. Generally, this entails preparing compositions that are essentially free of pyrogens, as well as other impurities that could be harmful to humans or animals.
Other embodiments of the disclosure provide particulate compositions coated with polymers (e.g., poloxamers or poloxamines). Still other embodiments of the compositions of the disclosure incorporate particulate forms protective coatings, protease inhibitors or permeation enhancers for various routes of administration, including parenteral, pulmonary, nasal and oral. In one embodiment the pharmaceutical composition is administered buccally, rectally, vaginally, topically, nasally, parenterally, paracancerally, transmucosally, transdermally, intramuscularly, intravenously, intradermally, subcutaneously, intraperitonealy, intraventricularly, intracranially, intratumorally, spray or in any other form effective to deliver active compositions.
For topical applications, the pharmaceutically acceptable carrier may take the form of a liquid, cream, foam, lotion, or gel, and may additionally comprise organic solvents, emulsifiers, gelling agents, moisturizers, stabilizers, surfactants, wetting agents, preservatives, time release agents, and minor amounts of humectants, sequestering agents, dyes, perfumes, and other components commonly employed in pharmaceutical compositions for topical administration.
Further, as used herein “pharmaceutically acceptable carrier” are well known to those skilled in the art and include, but are not limited to, 0.01-0.1M and preferably 0.05M phosphate buffer or 0.8% saline. Examples of non-aqueous solvents are propylene glycol, polyethylene glycol, vegetable oils such as olive oil, and injectable organic esters such as ethyl oleate. Aqueous carriers include water, alcoholic/aqueous solutions, emulsions or suspensions, including saline and buffered media.
Parenteral vehicles include sodium chloride solution, Ringer's dextrose, dextrose and sodium chloride, lactated Ringer's or fixed oils. Intravenous vehicles include fluid and nutrient replenishers, electrolyte replenishers such as those based on Ringer's dextrose, and the like. Preservatives and other additives may also be present, such as, for example, antimicrobials, antioxidants, collating agents, inert gases and the like.
Controlled or sustained release compositions include formulation in lipophilic depots (e.g, fatty acids, waxes, oils). Also comprehended by the disclosure are particulate compositions coated with polymers (e.g. poloxamers or poloxamines) and the compound coupled to antibodies directed against tissue-specific receptors, ligands or antigens or coupled to ligands of tissue-specific receptors.
Tablet and dosage forms of the compositions in which the emulsions are formulated for oral or topical administration include liquid capsules, and suppositories. In solid dosage forms for oral administration, the compositions may be admixed with one or more substantially inert diluent (e.g., sucrose, lactose, or starch, and the like) and may additionally comprise lubricating agents, buffering agents, enteric coatings, and other components well known to those skilled in the art.
Compounds modified by the covalent attachment of water-soluble polymers such as polyethylene glycol, copolymers of polyethylene glycol and polypropylene glycol, carboxymethyl cellulose, dextran, polyvinyl alcohol, polyvinylpyrrolidone or polyproline are known to exhibit substantially longer half-lives in blood following intravenous injection than do the corresponding unmodified compounds. Such modifications may also increase the compound's solubility in aqueous solution, eliminate aggregation, enhance the physical and chemical stability of the compound, and greatly reduce the immunogenicity and reactivity of the compound. As a result, the desired in vivo biological activity may be achieved by the administration of such polymer-compound abducts less frequently or in lower doses than with the unmodified compound.
In yet another embodiment, the pharmaceutical composition can be delivered in a controlled release system. For example, the agent may be administered using intravenous infusion, an implantable osmotic pump, a transdermal patch, liposomes, or other modes of administration. In one embodiment, a pump may be used (Sefton (1987). CRC Crit. Ref. Biomed. Eng. 14:201; Buchwald et al. (1980). Surgery 88:507; Saudek et al. (1989). N. Engl. J. Med. 321:574). In another embodiment, polymeric materials can be used. In yet another embodiment a controlled release system can be placed in proximity of the therapeutic target, i.e., the brain, thus requiring only a fraction of the systemic. Preferably, a controlled release device is introduced into a subject in proximity of the site of inappropriate immune activation or a tumor. Other controlled release systems are discussed in the review by Langer (1990). Science 249:1527-1533.
In other embodiments, the compositions may be impregnated into absorptive materials, such as sutures, bandages, and gauze, or coated onto the surface of solid phase materials, such as surgical staples, zippers and catheters to deliver the compositions to a site for the prevention of microbial infection. Other delivery systems of this type will be readily apparent to those skilled in the art.
Examples of suitable oily vehicles or solvents for use with the present disclosure are vegetable or animal oils such as sunflower oil or fish-liver oil. Preparations can be effected both as dry and as wet granules. For parenteral administration (subcutaneous, intravenous, intra-arterial, or intramuscular injection), the compositions or their physiologically tolerated derivatives such as salts, esters, N-oxides, and the like are converted into a solution, suspension, or emulsion, if desired with the substances customary and suitable for this purpose, for example, solubilizers or other auxiliaries. Examples are: sterile liquids such as water and oils, with or without the addition of a surfactant and other pharmaceutically acceptable adjuvants. Illustrative oils are those of petroleum, animal, vegetable, or synthetic origin, for example, peanut oil, soybean oil, or mineral oil. In general, water, saline, aqueous dextrose and related sugar solutions, and glycols such as propylene glycols or polyethylene glycol are preferred liquid carriers, particularly for injectable solutions.
In addition, if desired, the composition can contain minor amounts of auxiliary substances such as wetting or emulsifying agents, pH buffering agents which enhance the effectiveness of the active ingredient.
An active component can be formulated into the composition as neutralized pharmaceutically acceptable salt forms. Pharmaceutically acceptable salts include the acid addition salts (formed with the free amino groups of the polypeptide or antibody molecule) and which are formed with inorganic acids such as, for example, hydrochloric or phosphoric acids, or such organic acids as acetic, oxalic, tartaric, mandelic, and the like. Salts formed from the free carboxyl groups can also be derived from inorganic bases such as, for example, sodium, potassium, ammonium, calcium, or ferric hydroxides, and such organic bases as isopropylamine, trimethylamine, 2-ethylamino ethanol, histidine, procaine, and the like.
For topical administration to body surfaces using, for example, creams, gels, drops, and the like, the inhibitory nucleic acids and there prodrugs or their physiologically tolerated derivatives such as salts, esters, N-oxides, and the like are prepared and applied as solutions, suspensions, or emulsions in a physiologically acceptable diluent with or without a pharmaceutical carrier.
In another embodiment, the active compound can be delivered in a vesicle, in particular a liposome (see Langer (1990). Science, 249:1527-1533; Treat et al. (1989). in Lopez-Berestein and Fidler (eds.), Liposomes in the Therapy of Infectious Disease and Cancer, Liss, N.Y., pp. 353-365).
Suitable salts of the compositions disclosed herein include pharmaceutically acceptable salts. Other salts may, however, be useful, in the preparation of the compounds according to the disclosure or of their pharmaceutically acceptable salts. Suitable pharmaceutically acceptable salts of the compounds of this disclosure include acid addition salts which may, for example, be formed by mixing a solution of the compound according to the disclosure with a solution of a pharmaceutically acceptable acid such as hydrochloric acid, sulphuric acid, methanesulphonic acids fumaric acid, maleic acid, succinic acid, acetic acid, benzoic: acid, oxalic acid, citric acid, tartaric acid, carbonic acid or phosphoric acid.
It is also an aspect of this disclosure that a composition described herein, or its prodrug, salt, or derivative might be combined with other therapeurtic agents for the treatment of the diseases and disorders discussed above. Exemplary second agents include but are not limited to zinc salts of carboxylic acids, saponins, tritapenes, crataegolic acid, celastrol, asiatic acid, inhibitors of 5-α-reductase, 1,4-methyl-4-azasteroids, androgen receptor antagonists, Minoxidil, azelaic acid and its derivatives, cyclosporin, triiodothyronine, diazoxide and potassium channel openers, and combinations thereof.
Compositions disclosed here can be administered in a therapuetically acceptable amount. Generally, a therapeutically effective amount means an amount of compound effective to prevent, alleviate or ameliorate symptoms of disease such as inducing hair growth or preventing hair loss. Therapeutically effective amounts of compositions described herein can be approximately 10 mg/m2 to 400 mg/m2, preferably 50 mg/m2 to 300 mg/m2, more preferably 100 mg/m2 to 220 mg/m2, even more preferably 195 mg/m2. For any compound used in the methods of the disclosure, the therapeutically effective amount or dose can be estimated initially from cell culture assays. Then, the dosage can be formulated for use in animal models so as to achieve a circulating concentration range that includes the IC50 as determined in cell culture (i.e., the concentration of the test compound which achieves a half-maximal inhibition of the androgen signal transduction pathway). Such information can then be used to more accurately determine useful doses in humans.
Toxicity and therapeutic efficacy of the compounds described herein can be determined by standard pharmaceutical procedures in cell cultures or experimental animals, e.g., by determining the IC50 and the LD50 for a subject composition. The data obtained from these cell culture assays and animal studies can be used in formulating a range of dosage for use in humans. The dosage may vary depending upon the dosage form employed and the route of administration utilized. The exact formulation, route of administration and dosage can be chosen by the individual physician in view of the patient's condition. (See e.g., Hardman (2001) in The Pharmacological Basis of Therapeutics (10th edition) McGraw Hill).
Dosage amount and interval may be adjusted individually to provide plasma levels of the active species which are sufficient regulate the androgen signal transduction pathway to achieve the desired result, for example induction of hair growth or prevention of hair loss. The minimal effective plasma concentration levels will vary for each compound but can be estimated from in vitro data, e.g., the concentration necessary to achieve 50-90% inhibition of an androgen signal transduction pathway may be ascertained using the assays described herein. Preferably, the dosages necessary to achieve the minimal effective plasma concentration levels will depend on individual characteristics and route of administration. HPLC assays or bioassays can be used to determine plasma concentrations.
Dosage intervals can also be determined using minimal effective plasma concentration levels. Compounds should be administered using a regimen that maintains plasma levels above the minimal effective plasma concentration level for 10-90% of the time, preferably between 30-90% and most preferably between 50-90%. In cases of local administration or selective uptake, the effective local concentration of the compositions may not be related to plasma concentration and other procedures known in the art may be employed to determine the correct dosage amount and interval.
The amount of a composition administered will, of course, be dependent on the subject being treated, the severity of the affliction, the manner of administration, the judgment of the prescribing physician, etc.
The compositions may, if desired, be presented in a pack or dispenser device, such as an FDA approved kit, which may contain one or more unit dosage forms containing the compositions described herein. The pack may for example comprise metal or plastic foil, such as a blister pack. The pack or dispenser device may be accompanied by instructions for administration. The pack or dispenser may also be accompanied by a notice associated with the container in a form prescribed by a governmental agency regulating the manufacture, use or sale of pharmaceuticals, which notice is reflective of approval by the agency of the form of the compositions or of human or veterinary administration. Such notice, for example, may be of the labeling approved by the U.S. Food and Drug Administration for prescription drugs or of an approved product insert. Compositions comprising a compound of the disclosure formulated in a compatible pharmaceutical carrier may also be prepared, placed in an appropriate container, and labeled for treatment of an indicated condition. Suitable conditions indicated on the label may include treatment of a tumor, inhibition of angiogenesis, treatment of fibrosis, diabetes, and the like.
The effect of an inhibitory nucleic acid can be tested by assaying the telogen period in C3H mice (Harlan Sprague Dawley, Inc., Indianapolis, Ind.) from approximately 40 days of age until about 75 days of age, when hair growth is synchronized. It is believed that after 75 days of age, hair growth is no longer synchronized. Wherein about 40 day-old mice with dark fur (brown or black) are used in hair growth experiments, melanogenesis occurs along with hair (fur) growth wherein the topical application of hair growth promoters are evaluated. The Telogen Conversion Assay herein below can be used to screen compounds for potential hair growth by measuring melanogenesis.
For example, three groups of 44 day-old C3H mice can be utilized: a vehicle control group, a positive control group, and a test compound group, wherein the test compound group is administered a compound of the present disclosure. The length of the assay is at least 19 days with 15 treatment days (wherein the treatment days occur Mondays through Fridays). Day 1 is the first day of treatment. Most studies will end on Day 19, but a few may be carried out to Day 24 if the melanogenesis response looks positive, but occurs slowly.
Typically, the mice are treated topically Monday through Friday on their lower back (base of tail to the lower rib). A pipettor and tip are used to deliver 100-400 μL to each mouse's back: The 400 μL application is applied slowly while moving hair on the mouse to allow the application to reach the skin.
While each treatment is being applied to the mouse topically, a visual grade of from 0 to 4 can be given to the skin color in the application area of each animal. As the mice convert from telogen to anagen their skin color will become more bluish-black. The grades 0 to 4 represent the following visual observations as the skin progresses from white to bluish-black: Whitish Skin Color-0; Skin is light gray (indication of initiation of anagen)-1; Appearance of Blue Spots-2; Blue Spots are aggregating to form one large blue area-3; Skin is dark blue (almost black) with color covering majority of treatment area (indication of mouse in full anagen)-4.
Single-stranded, gene-specific sense and antisense RNA oligomers optionally with overhanging 3′ deoxynucleotides are prepared and purified by PAGE using the sequences listed in Tables 1-9 below. The two oligomers, 40 μM each, are annealed in 250 μl of buffer containing 50 mM Tris-HCl, pH 8.0 and 100 mM NaCl, by heating to 94° C. for 2 minutes, cooling to 90° C. for 1 minute, then cooling to 20° C. at a rate of 1° C. per minute. The resulting siRNA is stored at −20° C. prior to use.
The steroid 5-apha-reductase (SRD5a Locus Link id: 6715) was PCR amplified from the full-length cDNA clone (clone MGC: 12396 IMAGE: 3683274). Primers were designed to generate the full-length clone for TA-cloning into pcDNA 3.1 CT-GFP. As such, the reverse primer lacked a stop codon (Forward Primer: atgcaggttcagtgccagca [Seq ID No.: 1401]; Reverse Primer: ttaaaaagatgaatggaataag [Seq ID No.: 1402]) The 800 base pair product is shown in
To determine the inhibition of androgen signal transduction proteins with siRNAs prepared above, the siRNAs are administered to cell culture cells expressing androgen signal transduction pathway proteins such as the androgen receptor or 5α reductase. Exemplary cell lines expressing androgen signal transduction pathway proteins are found in the catalogue for American Tissue Type Culture which is incorporated herein in its entirety. Briefly, cell lines are maintained in RPMI 1640 media (GibcoBRL, Gaithersburg, Md.) containing 10% BCS. Varying amounts (150-350 μg/ml) of siRNA were added to the culture media. Cells are incubated under the same conditions, at 37° C., in 5% CO2 for 1-4 days. At the end of the incubation period, the cells are washed with PBS (phosphate buffered saline) and detached from the culture vessels using eversene. The cells are then assayed for expression of androgen signal transduction proteins such as androgen receptor and or 5α reductase.
The present disclosure is not to be limited in scope by the exemplified embodiments which are intended as illustrations of single aspects of the disclosure, and any clones, nucleic or amino acid sequences which are functionally equivalent are within the scope of the disclosure. Indeed, various modifications of the disclosure in addition to those described herein will become apparent to those skilled in the art from the foregoing description and accompanying drawings. Such modifications are intended to fall within the scope of the appended claims.
All references cited herein are hereby incorporated by reference in their entirety.
| Number | Date | Country | Kind |
|---|---|---|---|
| 60437842 | Jan 2003 | US | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/US04/00128 | 1/5/2004 | WO | 8/23/2006 |
