Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L31/00—Materials for other surgical articles, e.g. stents, stent-grafts, shunts, surgical drapes, guide wires, materials for adhesion prevention, occluding devices, surgical gloves, tissue fixation devices
  • A61L31/14—Materials characterised by their function or physical properties, e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
  • A61L31/16—Biologically active materials, e.g. therapeutic substances
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
  • A61L27/28—Materials for coating prostheses
  • A61L27/34—Macromolecular materials
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
  • A61L27/50—Materials characterised by their function or physical properties, e.g. injectable or lubricating compositions, shape-memory materials, surface modified materials
  • A61L27/54—Biologically active materials, e.g. therapeutic substances
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L29/00—Materials for catheters, medical tubing, cannulae, or endoscopes or for coating catheters
  • A61L29/08—Materials for coatings
  • A61L29/085—Macromolecular materials
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L29/00—Materials for catheters, medical tubing, cannulae, or endoscopes or for coating catheters
  • A61L29/14—Materials characterised by their function or physical properties, e.g. lubricating compositions
  • A61L29/16—Biologically active materials, e.g. therapeutic substances
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L31/00—Materials for other surgical articles, e.g. stents, stent-grafts, shunts, surgical drapes, guide wires, materials for adhesion prevention, occluding devices, surgical gloves, tissue fixation devices
  • A61L31/08—Materials for coatings
  • A61L31/10—Macromolecular materials
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L2300/00—Biologically active materials used in bandages, wound dressings, absorbent pads or medical devices

Definitions

• the present invention generally relates to chemical modification of biomedical materials, such as collagen matrix with a naturally occurring crosslinking reagent, genipin. More particularly, the present invention relates to solidifiable collagen-containing and/or chitosan-containing biological material loaded with drug that is configured suitable for drug slow release effective for therapeutic purposes, wherein the biological material is chemically treated with a crosslinking reagent, genipin, its derivatives or analog and the process of manufacture thereof.
• Crosslinking of biological molecules is often desired for optimum effectiveness in biomedical applications.
• collagen which constitutes the structural framework of biological tissue
• bioprostheses and other implanted structures such as vascular grafts, wherein it provides a good medium for cell infiltration and proliferation.
• biomaterials derived from collagenous tissue must be chemically modified and subsequently sterilized before they can be implanted in humans.
• the fixation, or crosslinking, of collagenous tissue increases strength and reduces antigenicity and immunogenicity.
• crosslinking of a drug-containing biological material with genipin enables the resulting material ("biological substance") with less antigenicity or immunogenicity, wherein the biological material comprises collagen, gelatin, elastin, chitosan, N, O, carboxylmethyl chitosan (NOCC), and the like that has at least one amino functional group for reaction with genipin.
• biological substance comprises collagen, gelatin, elastin, chitosan, N, O, carboxylmethyl chitosan (NOCC), and the like that has at least one amino functional group for reaction with genipin.
• Collagen sheets are also used as wound dressings, providing the advantages of high permeability to water vapor and rapid wound healing. Disadvantages include low tensile strength and easy degradation of collagen by collagenase. Crosslinking of collagen sheets reduces cleavage by collagenase and improves tensile strength.
• a collagen strip derived of crosslinked drug-containing collagen sheets may be used to load on the periphery of a stent as a drug-eluting stent to mitigate restenosis or other abnormality.
• the collagen sheet or collagen strip may be made of solidifiable collagen.
• biological tissue has been used in manufacturing heart valve prostheses, small-diameter vascular grafts, ligament replacements, and biological patches, among others.
• the biological tissue has to be fixed with a crosslinking or chemically modifying agent and subsequently sterilized before they can be implanted in humans.
• the fixation of biological tissue or collagen is to reduce antigenicity and immunogenicity and prevent enzymatic degradation.
• Various crosslinking agents have been used in fixing biological tissue.
• crosslinking agents are mostly synthetic chemicals such as formaldehyde, glutaraldehyde, dialdehyde starch, glyceraldehydes, cyanamide, diimides, diisocyanates, dimethyl adipimidate, carbodiimide, and epoxy compound.
• these chemicals are all highly cytotoxic which may impair the biocompatibility of biological tissue.
• glutaraldehyde is known to have allergenic properties, causing occupational dermatitis and is cytotoxic at concentrations greater than 10-25 ppm and as low as 3 ppm in tissue culture. It is therefore desirable to provide a crosslinking agent (synonymous to a crosslinking reagent) suitable for use in biomedical applications that is within acceptable cytotoxicity and that forms stable and biocompatible crosslinked products.
• genipin was tested in vitro using Chinese hamster ovary (CHO-K1) cells, suggesting that genipin does not cause clastogenic response in CHO-K1 cells (Tsai CC et al., J Biomed Mater Res 2000;52:58-65), incorporated herein by reference.
• a biological material including collagen-containing or chitosan-containing substrate treated with genipin resulting in acceptable cytotoxicity is a first requirement to biomedical applications.
• Atherosclerosis causes a partial blockage of the blood vessels that supply the heart with nutrients. Atherosclerotic blockage of blood vessels often leads to hypertension, ischemic injury, stroke, or myocardial infarction. Typically angioplasty and/or stenting is a remedy for such a disease, however, restenosis does occur in 30-40 percent patients resulting from intimal smooth muscle cell hyperplasia.
• the underlying cause of the intimal smooth muscle cell hyperplasia is mainly vascular smooth muscle injury and disruption of the endothelial lining.
• Vascular injury causing intimal thickening can be from mechanical injuries due to angioplasty and/or stenting. Intimal thickening following balloon catheter injury has been studied in animals as a model for arterial restenosis that occurs in human patients following balloon angioplasty. Injury is followed by a proliferation of the medial smooth muscle cells, after which many of them migrate into the intima through fenestrate in the internal elastic lamina and proliferate to form a neointimal lesion.
• Vascular stenosis can be detected and evaluated using angiographic or sonographic imaging techniques and is often treated by percutaneous transluminal coronary angioplasty (balloon catheterization). Within a few months following angioplasty, however, the blood flow is reduced in approximately 30-40 percent of these patients as a result of restenosis caused by a response to mechanical vascular injury suffered during the angioplasty or stenting procedure, as described above.
• lovastatin thromboxane A 2 synthetase inhibitors such as DP- 1904; eicosapentanoic acid; ciprostene (a prostacyclin analog); trapidil (a platelet derived growth factor)]; angiotensin convening enzyme inhibitors; and low molecular weight heparin, entire contents of the above-referred drugs and their therapeutic effects are incorporated herein by reference. It is one aspect of the present invention to provide site-specific administration of the pharmaceutical agents disclosed in this invention to the injury site for effective therapy via a genipin-crosslinked collagen-containing or chitosan-containing biological carrier.
• Rapamycin also known as sirolimus
• a macrocyclic triene antibiotic produced by Streptomyces hygroscopicus that has been shown to prevent the formation of humoral (IgE-like) antibodies in response to an albumin allergic challenge, inhibit murine T-cell activation, prolong survival time of organ gratis in histoincompatible rodents, and inhibit transplantation rejection in mammals.
• Rapamycin blocks calcium-dependent, calcium-independent, cytokine-independent and constitutive T and B cell division at the Gl-S Interface.
• Rapamycin inhibits gamma-interferon production induced by H -1 and also inhibits the gamma-interferon induced expression of membrane antigen.
• Arterial thickening following transplantation known as CGA, is a limiting factor in graft survival that is caused by a chronic immunological response to the transplanted blood vessels by the transplant recipient's immune system.
• polymer or plastic materials have been used as a carrier for depositing a drug or pharmaceutical agent onto the periphery of a stent to treat restenosis.
• Example is U.S. Pat. No. 5,886,016 to Hunter et al., entire contents of which are incorporated herein by reference.
• Hunter et al. discloses a method for treating a tumor excision site, comprising administering to a patient a composition comprising paclitaxel, or an analogue or derivative thereof, to the resection margin of a tumor subsequent to excision, such that the local recurrence of cancer and the formation of new blood vessels at the site is inhibited.
• the composition further comprises a polymer, wherein the polymer may comprise poly (caprolactone), poly (lactic acid), poly (ethylene-vinyl acetate), and poly (lactic-co-glycolic) acid.
• Biocompatibles PC phosphorylcholine by Biocompatibles, London, England
• the technique comprises a hydrophobic component that aids in the initial adhesion and film-formation of the polymer onto the stainless steel stent substrate, and other groups allow cross-linking both within the polymer and with the stent surface to achieve firm anchorage.
• the coating is thus tenaciously adhered to the stent and can survive balloon expansion without damage.
• a therapeutic drug can be loaded within the coated substrate, such as phosphorylcholine.
• Drugs are usually loaded, admixed or entrapped physically within the polymer framework for slow drug release.
• the plastic polymer which is suitable as a drug carrier may not be biocompatible, whereas some biocompatible plastic polymer may not be able to contain a specific drug and release drug in an effective timely amount for effective therapy. Therefore, there is a clinical need to have a biocompatible drug carrier that releases an effective quantity of drug over a period of time for prolonged therapeutic effects.
• genipin treated collagen-containing or chitosan-containing biological material loaded with drug for implant and other surgical applications which have shown to exhibit many of the desired characteristics important for optimal therapeutic function.
• the crosslinked collagen-drug compound with drug slow release capability may be suitable as anti restenosis agent in treating atherosclerosis and other therapeutic applications.
• the biological substance may be adhesively loaded onto a stent surface rendering the stent to slowly release drug from the biological substance.
• the "biological substance” is herein intended to mean a substance made of drug-containing biological material that is, in one preferred embodiment, solidifiable upon change of environmental condition(s) and is biocompatible post-crosslinking with a crosslinker, such as genipin, its derivatives, analog, stereoisomers and mixtures thereof.
• the crosslinker may further comprise epoxy compounds, dialdehyde starch, glutaraldehyde, formaldehyde, dimethyl suberimidate, carbodiimides, succinimidyls, diisocyanates, acyl azide, ultraviolet irradiation, dehydrothermal treatment, tris(hydroxymethyl)phosphine, ascorbate-copper, glucose-lysine and photo-oxidizers, and the like.
• the "biological material” is intended herein to mean collagen, gelatin, elastin, chitosan, NOCC (N, O, carboxylmethyl chitosan), and the like that could be crosslinked with a crosslinker (also known as a crosslinking agent).
• the process of preparing a biological substance comprises steps, in combination, of loading drugs with the biological material, shaping the drug-containing biological material, followed by crosslinking with genipin.
• the genipin referred herein is broadly consisted of the naturally occurring compound as shown in FIG. 1 and its derivatives, analog, stereoisomers and mixtures thereof.
• the drug-containing biological material is further coated, adhered or loaded onto a physical construct or apparatus before or after crosslinking with a crosslinker (such as genipin).
• the biological material is herein broadly generally referred to collagen, elastin, gelatin, chitosan, NOCC, the mixtures thereof, and derivates, analog and mixtures thereof.
• the biological material may be in a form or phase of solution, paste, gel, suspension, colloid or plasma that is solidifiable thereafter.
• the medical device can be a stent, a non-stent implant or prosthesis, or a percutaneous device such as a catheter, a wire, a cannula, an endoscopic instrument or the like for the intended drug slow release.
• the non-stent implant may comprise biological implant, non-biological implant, annuloplasty rings, heart valve prostheses, venous valve bioprostheses, orthopedic implants, dental implants, ophthalmology implants, cardiovascular implants, and cerebral implants.
• the amine or amino group of the drug is reacted with the amino group of collagen through a crosslinker.
• FIG. 1 is chemical structures of glutaraldehyde and genipin that are used in the chemical treatment examples of the current disclosure.
• FIG. 2A is an iridoid glycoside present in fruits of Gardenia jasmindides Ellis
• FIG. 2B is a parent compound geniposide (Structure 11) from which genipin is derived.
• FIG. 3 is a proposed crosslinking mechanism for a crosslinker, glutaraldehyde (GA) with collagen intermolecularly and or intramolecularly.
• FIG. 4A is a proposed reaction mechanism between genipin and an amino group of a reactant, including collagen or certain type of drug of the present invention.
• FIG. 4B is a proposed crosslinking mechanism for a crosslinker, genipin (GP) with collagen intermolecularly and/or intramolecularly.
• FIG. 5 is a schematic illustration for genipin to crosslink an amino-containing collagen and an amino-containing drug.
• FIG. 6 is an illustrated example of a cross-sectional view for a vascular stent coated with drug-containing collagen crosslinked with genipin according to the principles of the present invention.
• Genepin in this invention is meant to refer to the naturally occurring compound as shown in FIG. 1 and its derivatives, analog, stereoisomers and mixtures thereof.
• Crosslinking agent is meant herein to indicate a chemical agent that could crosslink two molecules, such as formaldehyde, glutaraldehyde, dialdehyde starch, glyceraldehydes, cyanamide, diimides, diisocyanates, dimethyl adipimidate, carbodiimide, and epoxy compound.
• Bio material is herein meant to refer to collagen extract, soluble collagen, elastin, gelatin, chitosan, chitosan-containing and other collagen-containing biological material.
• the biological material is meant to indicate a solidifiable biological substrate comprising at least a genipin-crosslinkable functional group, such as amino group or the like.
• a “biological implant” refers to a medical device which is inserted into, or grafted onto, bodily tissue to remain for a period of time, such as an extended-release drug delivery device, drug-eluting stent, vascular or skin graft, or orthopedic prosthesis, such as bone, ligament, tendon, cartilage, and muscle.
• the crosslinked collagen-drug device or compound with drug slow release capability may be suitable as anti restenosis agent in treating atherosclerosis and other therapeutic applications.
• a medical device comprising an apparatus having a surface (for example, a coronary stent), a bioactive agent, and biological material loaded onto at least a portion of the surface of the apparatus, the biological material comprising the bioactive agent, wherein the biological material is thereafter crosslinked with a crosslinking agent.
• the biological material comprises a solidifiable substrate and the device further comprises a step of solidifying the solidifiable substrate.
• a medical device comprising an apparatus having a surface (for example, a coronary stent or heart valve), a bioactive agent, and biological material, the biological material being crosslinked with a crosslinking agent, wherein the biological material is thereafter mixed with the bioactive agent and loaded onto at least a portion of the surface of the apparatus.
• drug in this invention is meant to broadly refer to a chemical molecule(s), biological molecule(s) or bioactive agent providing a therapeutic, diagnostic, or prophylactic effect in vivo.
• drug and bioactive agent may comprise, but not limited to, synthetic chemicals, biotechnology-derived molecules, herbs, cells, genes, growth factors, health food and/or alternate medicines.
• drug and bioactive agent are used interchangeably.
• a blood vessel is generally consisted of a support structure for transporting blood and a luminal blood-contacting surface lined with a layer of endothelial cells.
• endothelialization which involves the migration of endothelial cells from adjacent tissue onto the denuded luminal surface, can occur as a part of the healing process.
• self-endothelialization occurs to only a limited degree and the limited endothelialization that does occur takes place slowly.
• endothelial cells can be seeded or loaded onto an implant, for example, a drug-eluting device of the present invention, before the implant is placed in the recipient.
• the "biological substance” is herein intended to mean a substance made of drug-containing biological material that is, in one preferred embodiment, solidifiable upon change of environmental condition(s) and is biocompatible after being crosslinked with a crosslinker, such as genipin, epoxy compounds, dialdehyde starch, glutaraldehyde, formaldehyde, dimethyl adipimidate, carbodiimide, or the like.
• a crosslinker such as genipin, epoxy compounds, dialdehyde starch, glutaraldehyde, formaldehyde, dimethyl adipimidate, carbodiimide, or the like.
• the "biological material” is intended herein to mean collagen, gelatin, elastin, chitosan, N, O, carboxylmethyl chitosan (NOCC), chitosan-containing material, collagen-containing material, and the like that could be crosslinked with a crosslinker (also known as a crosslinking agent).
• Genipin shown in Structure I of FIG. 2A, is an iridoid glycoside present in fruits
• Genipin the aglycone of geniposide
• Genipin may be prepared from the latter by oxidation followed by reduction and hydrolysis or by enzymatic hydrolysis.
• racemic genipin may be prepared synthetically.
• Structure I shows the natural configuration of genipin, any stereoisomer or mixture of stereoisomers of genipin as shown later may be used as a crosslinking reagent, in accordance with the present invention.
• Genipin has a low acute toxicity, with LD 50 i.v. 382 mg/k in mice. It is therefore much less toxic than glutaraldehyde and many other commonly used synthetic crosslinking reagents. As described below, genipin is shown to be an effective crosslinking agent for treatment of biological materials intended for in vivo biomedical applications, such as prostheses and other implants, wound dressings, and substitutes.
• the compound is loaded onto the outer periphery of the stent enabling drug slow-release to the surrounding tissue.
• Chang in U.S. Pat. No. 5,929,038 discloses a method for treating hepatitis B viral infection with an iridoid compound of a general formula containing a six-member hydrocarbon ring sharing with one common bondage of a five-member hydrocarbon ring.
• Moon et al. in U.S. Pat. No. 6,162,826 and No. 6,262,083 discloses genipin derivatives having anti hepatitis B virus activity and liver protection activity. All of which three aforementioned patents are incorporated herein by reference.
• the genipin derivatives and/or genipin analog may have the following chemical formulas (Formula 1 to 4):
• i represents lower alkyl
• R 2 represents lower alkyl, pyridylcarbonyl, benzyl or benzoyl;
• R 3 represents formyl, hydroxymethyl, azidomethyl, 1-hydroxyethyl, acetyl, methyl, hydroxy, pyridylcarbonyl, cyclopropyl, aminomethyl substituted or unsubstituted by (l,3-benzodioxolan-5-yl)carbonyl or
• R 3 is not methyl formyl, hydroxymethyl, acetyl, methylaminomethyl, acetylthiomethyl, benzoyloxymethyl or pyridylcarbonyloxyrnefhyl when R t is methyl, and
• j represents lower alkoxy, benzyloxy, benzoyloxy, phenylthio, C ⁇ C ⁇ 2 alkanyloxy substituted or unsubstituted by t-butyl, phenyl, phenoxy, pyridyl or thienyl;
• R s represents methoxycarbonyl, formyl, hydroxyiminomethyl, methoxyimino-methyl, hydroxymethyl, phenylthiomethyl or acetylthiomethyl; [0057] provided that R 5 is not methoxycarbonyl when R J4 is acetyloxy; and
• Re represents hydrogen atom, lower alkyl or alkalimetal
• R 7 represents lower alkyl or benzyl
• R 8 represents hydrogen atom or lower alkyl
• R 9 represents hydroxy, lower alkoxy, benzyloxy, nicotinoyloxy, isonicotinoyloxy,
• R 10 represents lower alkyl
• Rji represents lower alkyl or benzyl
• R 12 represents lower alkyl, pyridyl substituted or unsubstituted by halogen, pyridylamino substituted or unsubstituted by lower alkyl or halogen, 1 ,3 -benzodioxolanyl;
• Rj 3 and R M each independently represent a hydrogen atom or join together to form isopropylidene; and [0070] its pharmaceutically acceptable salts, or stereoisomers.
• 0366998 entire contents of all three being incorporated herein by reference, teach the crosslinking of amino group containing compounds with genipin and the crosslinking of genipin with chitosan. They also teach the crosslinking of iridoid compounds with proteins which can be vegetable, animal (collagen, gelatin) or microbial origin. However, they do not teach loading drug onto a collagen-containing biological material crosslinked with genipin as biocompatible drug carriers for drug slow-release.
• Noishiki et al. in U.S. Pat. 4,806,595 discloses a tissue treatment method by a crosslinking agent, polyepoxy compounds.
• Collagens used in that patent include an insoluble collagen, a soluble collagen, an atelocollagen prepared by removing telopeptides on the collagen molecule terminus using protease other than collagenase, a chemically modified collagen obtained by succinylation or esterification of above-described collagens, a collagen derivative such as gelatin, a polypeptide obtained by hydrolysis of collagen, and a natural collagen present in natural tissue (ureter, blood vessel, pericardium, heart valve, etc.)
• the Noishiki et al. patent is incorporated herein by reference.
• "Biological material" in the present invention is additionally used herein to refer to the above-mentioned collagen, collagen species, collagen in natural tissue, and collagen in a biological implant preform that are shapeable and/or solidifiable.
• Voytik-Harbin et al. in U.S. Pat. No. 6,264,992 discloses submucosa as a growth substrate for cells. More particularly, the submucosa is enzymatically digested and gelled to form a shape retaining gel matrix suitable for inducing cell proliferation and growth both in vivo and in vitro.
• the Voytik-Harbin et al. patent is incorporated herein by reference.
• Biological material additionally including submucosa, that is chemically modified or treated by genipin or other crosslinker of the present invention may serve as a shapeable raw material for making a biological substance adapted for inducing cell proliferation and ingrowth, but also resisting enzymatic degradation, both in vivo and in vitro.
• drug is loaded with submucosa biological material and crosslinked with a crosslinker, such as genipin.
• Cook et al. in U.S. Pat. No. 6,206,931 discloses a graft prosthesis material including a purified, collagen-based matrix structure removed from a submucosa tissue source, wherein the submucosa tissue source is purified by disinfection and removal steps to deactivate and remove contaminants.
• the Cook et al. patent is incorporated herein by reference.
• a collagen-based matrix structure also known as "biological material” in this disclosure, may serve as a biomaterial adapted for medical device use after chemical modification by genipin of the present invention.
• Levene et al. in U.S. Pat. No. 6,103,255 discloses a porous polymer scaffold for tissue engineering, whereby the scaffold is characterized by a substantially continuous solid phase, having a highly interconnected bimodal distribution of open pore sizes.
• the Levene et al. patent is incorporated herein by reference.
• the present invention discloses biological scaffold material by acellular process and acidic/enzymatic treatment adapted for tissue engineering. Additional benefits of genipin tissue treatment for reduced antigenicity, reduced cytotoxicity and enhanced biodurability on a drug-containing biological substance are disclosed in the present invention.
• Some aspects of the invention provide an acellular tissue with a natural or enlarged microenvironment for host cell migration, in vitro endothelialization, or in vivo endothelialization to accelerate tissue regeneration.
• a method for treating tissue of a patient comprising, in combination, loading a drug-containing biological material onto an apparatus or medical device, an optional step of solidifying the drug-containing biological material, chemically treating the drug-containing biological material with a crosslinking agent, and delivering the medical device to a target tissue for releasing the drug and treating the tissue.
• the collagen-drug-genipin compound or the chitosan-drug-genipin compound and methods of manufacture as disclosed and supported in the below examples produce new and unexpected results and hence are unobvious from the prior art.
• the medical device can be a stent, a non-stent implant or prosthesis, or a percutaneous device such as a catheter, a wire, a cannula, an endoscopic instrument or the like for the intended drug slow release. Further, the medical device can be a biological device or a non-biological device.
• the stent application with collagen-drug-genipin compound or the chitosan-drug-genipin compound comprises use in lymphatic vessel, gastrointestinal tract (including the various ducts such as hepatic duct, bile duct, pancreatic duct, etc.), urinary tract (ureter, urethra, etc.), and reproductive tract (i.e., uterine tube, etc.).
• the non-stent implant may comprise annuloplasty rings, heart valve prostheses, venous valve bioprostheses, orthopedic implants, dental implants, ophthalmology implants, cardiovascular implants, and cerebral implants.
• the target tissue may comprise vulnerable plaque, atherosclerotic plaque, tumor or cancer, brain tissue, vascular vessel or tissue, orthopedic tissue, ophthalmology tissue or the like.
• the vulnerable plaque is the atherosclerotic plaque that is vulnerably prone to rupture in a patient.
• a biological substance for treating tissue of a patient with drug slow release wherein the biological substance is made of drug-containing biological material that may be solidifiable upon change of environmental condition(s) and is biocompatible after being crosslinked with a crosslinker, such as genipin, epoxy compounds, dialdehyde starch, dimethyl adipimidate, carbodiimide, glutaraldehyde, or the like.
• a crosslinker such as genipin, epoxy compounds, dialdehyde starch, dimethyl adipimidate, carbodiimide, glutaraldehyde, or the like.
• a method for treating tissue of a patient comprising, in combination, mixing a drug with a biological material, chemically treating the drug with the biological material with a crosslinking agent, loading the drug-containing biological material onto an apparatus or medical device.
• the method further comprises a step of solidifying the drug-containing biological material.
• the method may further comprise chemically linking the drug with the biological material through a crosslinker, wherein the drug comprises at least a crosslinkable functional group, for example, an amino group.
• It is a further aspect of the present invention to provide a method for treating vascular restenosis comprising, in combination, loading a drug-containing biological material onto a medical device, chemically treating the drug-containing biological material with a crosslinking agent, and delivering the medical device to a vascular restenosis site for treating the vascular restenosis.
• the method further comprises a step of solidifying the drug-containing biological material, wherein at least a portion of the biological material comprises a solidifiable substrate or material.
• the drugs used in the current generation drug eluting cardiovascular stents include two major mechanisms: cytotoxic and cytostatic.
• Some aspects of the invention relating to the drugs used in collagen-drug-genipin compound from the category of cytotoxic mechanism comprise actinomycin D, paclitaxel, vincristin, methotrexate, and angiopeptin.
• Some aspects of the invention relating to the drugs used in collagen-drug-genipin compound from the category of cytostatic mechanism comprise batimastat, halofuginone, sirolimus, tacrolimus, everolimus, tranilast, dexamethasone, and mycophenolic acid (MPA).
• MPA mycophenolic acid
• bioactive agent in a bioactive agent-eluting device, wherein the bioactive agent is selected from a group consisting of actinomycin D, paclitaxel, vincristin, methotrexate, and angiopeptin, batimastat, halofuginone, sirolimus, tacrolimus, everolimus, tranilast, dexamethasone, and mycophenolic acid.
• the bioactive agent is selected from a group consisting of actinomycin D, paclitaxel, vincristin, methotrexate, and angiopeptin, batimastat, halofuginone, sirolimus, tacrolimus, everolimus, tranilast, dexamethasone, and mycophenolic acid.
• Everolimus with molecular weight of 958 (a chemical formula of C5 3 H 83 NO 14 ) is poorly soluble in water and is a novel proliferation inhibitor. There is no clear upper therapeutic limit of everolimus. However, thrombocytopenia occurs at a rate of 17% at everolimus trough serum concentrations above 7.8 ng/ml in renal transplant recipients (Expert Opin Investig Drugs 2002;11(12):1845-1857). In a patient, everolimus binds to cytosolic immunophyllin FKBP12 to inhibit growth factor-driven cell proliferation. Everolimus has shown promising results in animal studies, demonstrating a 50% reduction of neointimal proliferation compared with a control bare metal stent.
• analgesics/antipyretics e.g., aspirin, acetaminophen, ibuprofen, naproxen sodium, buprenorphine, propoxyphene hydrochloride, propoxyphene napsylate, meperidine hydrochloride, hydromorphone hydrochloride, morphine, oxycodone, codeine, dihydrocodeine bitartrate, pentazocine, hydrocodone bitartrate, levorphanol, diflunisal, trolamine salicylate, nalbuphine hydrochloride, mefenamic acid, butorphanol, choline salicylate, butalbital, phenyltoloxamine citrate, diphenhydramine citrate, methotrimeprazine, cinnamedrine hydrochloride, and meprobamate);
• aspirin e.g., aspirin, acetaminophen, ibuprofen, naproxen sodium, buprenor
• antiasthamatics e.g., ketotifen and traxanox
• antibiotics e.g., neomycin, streptomycin, chloramphenicol, cephalosporin, ampicillin, penicillin, tetracycline, and ciprofloxacin
• antidepressants e.g., nefopam, oxypertine, doxepin, amoxapine, trazodone, amitriptyline, maprotiline, phenelzine, desipramine, nortriptyline, tranylcypromine, fluoxetine, doxepin, imipramine, imipramine pamoate, isocarboxazid, trimipramine, and protriptyline);
• antidepressants e.g., nefopam, oxypertine, doxepin, amoxapine, trazodone, amitriptyline, maprotiline, phenelzine, desipramine, nortriptyline, tranylcypromine, fluoxetine, doxepin, imipramine, imipramine pamoate, isocarboxazid, trimipramine, and protriptyline);
• antidiabetics e.g., biguanides and sulfonylurea derivatives
• antifimgal agents e.g., griseofulvin, ketoconazole, itraconizole, amphotericin B, nystatin, and candicidin
• antihypertensive agents e.g., propanolol, propafenone, oxyprenolol, nifedipine, reserpine, trimethaphan, phenoxybenzamine, pargyline hydrochloride, deserpidine, diazoxide, guanethidine monosulfate, minoxidil, rescinnamine, sodium nitroprusside, rauwolfia serpentina, alseroxylon, and phentolamine);
• antihypertensive agents e.g., propanolol, propafenone, oxyprenolol, nifedipine, reserpine, trimethaphan, phenoxybenzamine, pargyline hydrochloride, deserpidine, diazoxide, guanethidine monosulfate, minoxidil, rescinnamine, sodium nitroprusside, rauwolfia serpentina,
• anti-inflammatories e.g., (non-steroidal) indomethacin, ketoprofen, flurbiprofen, naproxen, ibuprofen, ramifenazone, piroxicam, (steroidal) cortisone, dexamethasone, fluazacort, celecoxib, rofecoxib, hydrocortisone, prednisolone, and prednisone);
• antineoplastics e.g., cyclophosphamide, actinomycin, bleomycin, daunorubicin, doxorubicin hydrochloride, epirubicin, mitomycin, methotrexate, fluorouracil, carboplatin, carmustine (TBCNU), methyl-CCNU, cisplatin, etoposide, camptothecin and derivatives thereof, phenesterine, paclitaxel and derivatives thereof, docetaxel and derivatives thereof, vinblastine, vincristine, tamoxifen, piposulfan);
• antineoplastics e.g., cyclophosphamide, actinomycin, bleomycin, daunorubicin, doxorubicin hydrochloride, epirubicin, mitomycin, methotrexate, fluorouracil, carboplatin, carmustine (TBCNU), methyl-CCNU, cisplatin, etop
• antianxiety agents e.g., lorazepam, buspirone, prazepam, chlordiazepoxide, oxazepam, clorazepate dipotassium, diazepam, hydroxyzine pamoate, hydroxyzine hydrochloride, alprazolam, droperidol, halazepam, chlormezanone, and dantrolene
• lorazepam buspirone
• prazepam chlordiazepoxide
• oxazepam clorazepate dipotassium
• diazepam hydroxyzine pamoate
• hydroxyzine hydrochloride alprazolam
• droperidol halazepam
• chlormezanone e.g., halazepam, chlormezanone, and dantrolene
• immunosuppressive agents e.g., cyclosporine, azathioprine, mizoribine, and FK506
• antimigraine agents e.g., ergotamine, propanolol, isometheptene mucate, and dichloralphenazone
• antimigraine agents e.g., ergotamine, propanolol, isometheptene mucate, and dichloralphenazone
• sedatives/hypnotics e.g., barbiturates such as pentobarbital, pentobarbital, and secobarbital; and benzodiazapines such as flurazepam hydrochloride, triazolam, and midazolam);
• antianginal agents e.g., beta-adrenergic blockers; calcium channel blockers such as nifedipine, and diltiazem; and nitrates such as nitroglycerin, isosorbide dinitrate, pentaerythritol tetranitrate, and erythrityl tetranitrate);
• antipsychotic agents e.g., haloperidol, loxapine succinate, loxapine hydrochloride, thioridazine, thioridazine hydrochloride, thiothixene, fluphenazine, fluphenazine decanoate, fluphenazine enanthate, trifluoperazine, chlorpromazine, perphenazine, lithium citrate, and prochlorperazine);
• antimanic agents e.g., lithium carbonate
• antiarrhythmics e.g., bretylium tosylate, esmolol, verapamil, amiodarone, encainide, digoxin, digitoxin, mexiletine, disopyramide phosphate, procainamide, quinidine sulfate, quinidine gluconate, quinidine polygalacturonate, flecainide acetate, tocainide, and lidocaine);
• antiarthritic agents e.g., phenylbutazone, sulindac, penicillanine, salsalate, piroxicam, azathioprine, indomethacin, meclofenamate, gold sodium thiomalate, ketoprofen, auranofin, aurothioglucose, and tolmetin sodium
• antigout agents e.g., colchicine, and allopurinol
• anticoagulants e.g., heparin, heparin sodium, and warfarin sodium
• thrombolytic agents e.g., urokinase, streptokinase, and alteplase
• antifibrinolytic agents e.g., aminocaproic acid
• hemorheologic agents e.g., pentoxifylline
• antiplatelet agents e.g., aspirin
• anticonvulsants e.g., valproic acid, divalproex sodium, phenytoin, phenytoin sodium, clonazepam, primidone, phenobarbitol, carbamazepine, amobarbital sodium, methsuximide, metharbital, mephobarbital, mephenytoin, phensuximide, paramethadione, ethotoin, phenacemide, secobarbitol sodium, clorazepate dipotassium, and trimethadione);
• antiparkinson agents e.g., ethosuximide
• antihistamines/antipruritics e.g., hydroxyzine, diphenhydramine, chlorpheniramine, brompheniramine maleate, cyproheptadine hydrochloride, terfenadine, clemastine fumarate, triprolidine, carbinoxamine, diphenylpyraline, phenindamine, azatadine, tripelennamine, dexchlorphenirarnine maleate, methdilazine, and);
• agents useful for calcium regulation e.g., calcitonin, and parathyroid hormone
• antibacterial agents e.g., amikacin sulfate, aztreonam, chloramphenicol, chloramphenicol palirtate, ciprofloxacin, clindamycin, clindamycin palmitate, clindamycin phosphate, metronidazole, metronidazole hydrochloride, gentamicin sulfate, lincomycin hydrochloride, tobramycin sulfate, vancomycin hydrochloride, polymyxin B sulfate, colistimethate sodium, and colistin sulfate);
• amikacin sulfate e.g., amikacin sulfate, aztreonam, chloramphenicol, chloramphenicol palirtate, ciprofloxacin, clindamycin, clindamycin palmitate, clindamycin phosphate, metronidazole, metronidazole hydrochloride,
• antiviral agents e.g., interferon alpha, beta or gamma, zidovudine, amantadine hydrochloride, ribavirin, and acyclovir
• antimicrobials e.g., cephalosporins such as cefazolin sodium, cephradine, cefaclor, cephapirin sodium, ceftizoxime sodium, cefoperazone sodium, cefotetan disodium, cefuroxime azotil, cefotaxime sodium, cefadroxil monohydrate, cephalexin, cephalothin sodium, cephalexin hydrochloride monohydrate, cefamandole nafate, cefoxitin sodium, cefonicid sodium, ceforanide, ceftriaxone sodium, ceftazidime, cefadroxil, cephradine, and cefuroxime sodium; penicillins such as ampicillin, amoxicillin, penicillin G benzathine, cyclacillin, ampicillin sodium, penicillin G potassium, penicillin V potassium, piperacillin sodium, oxacillin sodium, bacampicillin hydrochloride, cloxacillin sodium,
• anti-infectives e.g., GM-CSF
• bronchodilators e.g., sympathomimetics such as epinephrine hydrochloride, metaproterenol sulfate, terbutaline sulfate, isoetharine, isoetharine mesylate, isoetharine hydrochloride, albuterol sulfate, albuterol, bitolterolmesylate, isoproterenol hydrochloride, terbutaline sulfate, epinephrine bitartrate, metaproterenol sulfate, epinephrine, and epinephrine bitartrate; anticholinergic agents such as ipratropium bromide; xanthines such as aminophylline, dyphylline, metaproterenol sulfate, and aminophylline; mast cell stabilizers such as cromolyn sodium; inhalant corticosteroids such as beclo
• steroidal compounds and hormones e.g., androgens such as danazol, testosterone cypionate, fluoxymesterone, ethyltestosterone, testosterone enathate, methyltestosterone, fluoxymesterone, and testosterone cypionate; estrogens such as estradiol, estropipate, and conjugated estrogens; progestins such as methoxyprogesterone acetate, and norethindrone acetate; corticosteroids such as triamcinolone, betamethasone, betamethasone sodium phosphate, dexamethasone, dexamethasone sodium phosphate, dexamethasone acetate, prednisone, methylprednisolone acetate suspension, triamcinolone acetonide, methylprednisolone, prednisolone sodium phosphate, methylprednisolone sodium succinate, hydrocortisone sodium succinate,
• hypoglycemic agents e.g., human insulin, purified beef insulin, purified pork insulin, glyburide, chlorpropamide, glipizide, tolbutarnide, and tolazamide;
• hypolipidemic agents e.g., clofibrate, dextrothyroxine sodium, probucol, pravastitin, atorvastatin, lovastatin, and niacin
• hypolipidemic agents e.g., clofibrate, dextrothyroxine sodium, probucol, pravastitin, atorvastatin, lovastatin, and niacin
• proteins e.g., DNase, alginase, superoxide dismutase, and lipase
• nucleic acids e.g., sense or anti-sense nucleic acids encoding any therapeutically useful protein, including any of the proteins described herein;
• agents useful for erythropoiesis stimulation e.g., erythropoietin
• antiulcer/antireflux agents e.g., famotidine, cimetidine, and ranitidine hydrochloride
• antinauseants/antiemetics e.g., meclizine hydrochloride, nabilone, prochlorperazine, dimenhydrinate, promethazine hydrochloride, thiethylperazine, and scopolamine
• [0127] as well as other drags useful in the compositions and methods described herein include mitotane, halonitrosoureas, anthrocyclines, ellipticine, ceftriaxone, ketoconazole, ceftazidime, oxaprozin, albuterol, valacyclovir, urofollitropin, famciclovir, flutamide, enalapril, mefformin, itraconazole, buspirone, gabapentin, fosinopril, tramadol, acarbose, lorazepan, follitropin, glipizide, omeprazole, fluoxetine, lisinopril, tramsdol, levofloxacin, zafirlukast, interferon, growth hormone, interleukin, erythropoietin, granulocyte stimulating factor, nizatidine, bupropion, perindopril
• Preferred drugs useful in the present invention may include albuterol, adapalene, doxazosin mesylate, mometasone furoate, ursodiol, amphotericin, enalapril maleate, felodipine, nefazodone hydrochloride, valrubicin, albendazole, conjugated estrogens, medroxyprogesterone acetate, nicardipine hydrochloride, zolpidem tartrate, amlodipine besylate, ethinyl estradiol, omeprazole, rubitecan, amlodipine besylate/ benazepril hydrochloride, etodolac, paroxetine hydrochloride, paclitaxel, atovaquone, felodipine, podof ⁇ lox, paricalcitol, betamethasone dipropionate, fentanyl, pramipexole dihydrochloride
• drugs that fall under the above categories include paclitaxel, docetaxel and derivatives, epothilones, nitric oxide release agents, heparin, aspirin, coumadin, PPACK, hirudin, polypeptide from angiostatin and endostatin, methotrexate, 5-fluorouracil, estradiol, P-selectin Glycoprotein ligand-1 chimera, abciximab, exochelin, eleutherobin and sarcodictyin, fludarabine, sirolimus, tranilast, VEGF, transforming growth factor (TGF)-beta, Insulin-like growth factor (IGF), platelet derived growth factor (PDGF), fibroblast growth factor (FGF), RGD peptide, beta or gamma ray emitter (radioactive) agents, and dexamethasone, tacrolimus, actinomycin-D, batim
• Sirolimus is a naturally occurring macrolide antibiotic produced by the fungus
• Sirolimus with molecular weight of 916 (a chemical formula of C 5 ⁇ H 79 NO ⁇ 3 ) is non-water soluble and is a potential inhibitor of cytokine and growth factor mediated cell proliferation.
• the drug may broadly comprise, but not limited to, synthetic chemicals, biotechnology-derived molecules, herbs, health food, extracts, and/or alternate medicines; for example, including allicin and its corresponding garlic extract, ginsenosides and the corresponding ginseng extract, flavone/terpene lactone and the corresponding ginkgo biloba extract, glycyrrhetinic acid and the corresponding licorice extract, and polyphenol proanthocyanides and the corresponding grape seed extract.
• synthetic chemicals for example, including allicin and its corresponding garlic extract, ginsenosides and the corresponding ginseng extract, flavone/terpene lactone and the corresponding ginkgo biloba extract, glycyrrhetinic acid and the corresponding licorice extract, and polyphenol proanthocyanides and the corresponding grape seed extract.
• crosslinking In the present invention, the terms “crosslinking”, “fixation”, “chemical modification”, and “chemical treatment” for tissue are used interchangeably.
• FIG. 1 shows chemical structures of glutaraldehyde and genipin that are used in the chemical treatment examples of the current disclosure.
• Other crosslink agents may equally be applicable for collagen-drug-genipin and/or chitosan-drug-genipin compound disclosed herein.
• the crosslinking agent that may be used in chemical treatment of the present invention may include formaldehyde, dialdehyde starch, glyceraldehydes, cyanamide, diimides, diisocyanates, dimethyl adipimidate, carbodiimide, and epoxy compound.
• FIG. 3 shows a proposed crosslinking mechanism for a crosslinker, glutaraldehyde
• FIG. 4A shows a proposed reaction mechanism between genipin and an amino group of a reactant, including collagen or certain type of drug of the present invention
• FIG. 4B shows a proposed crosslinking mechanism for a crosslinker, genipin (GP) with collagen intermolecularly and/or intramolecularly.
• FIG. 5 is a schematic illustration for genipin to crosslink an amino-containing collagen and an amino-containing drug. It is also conceivable for a crosslinker, such as genipin to link an amine-containing substrate and an amino-containing drug.
• a crosslinker such as genipin to link an amine-containing substrate and an amino-containing drug.
• An example of amine-containing substrate is polyurethane and the like.
• Glutaraldehyde has been used extensively as a crosslinking agent for fixing biologic tissues.
• glutaraldehyde reacts primarily with the ⁇ -amino groups of lysyl or hydroxylysyl residues within biologic tissues.
• the mechanism of fixation of biologic tissues or biologic matrix with glutaraldehyde can be found elsewhere. Polymerization of glutaraldehyde molecules in aqueous solution with observable reductions in free aldehyde have been reported previously (Nimni ME et al. in Nimni ME, editor. COLLAGEN. Vol. III. Boca Raton (FL); CRC Press 1998. pp. 1-38).
• a substance for example, a drug
• glutaraldehyde As illustrated above, collagen, glutaraldehyde and a drug having an amine or amino group, the crosslinked compound may link collagen to the drug via glutaraldehyde as a crosslinker.
• biocompatible plastic polymers or synthetic polymers have one or more amine group in their chemical structures.
• the amine group may become reactive toward a crosslinker, such as glutaraldehyde, genipin or epoxy compounds. Therefore, it is conceivable that by combining a polymer having an amine group, glutaraldehyde and a drug having at least an amine or amino group, the crosslinked compound may have the polymer linked to the drug via glutaraldehyde as a crosslinker.
• Other crosslinkers are also applicable.
• the blue-pigment was thought formed through oxygen radical-induced polymerization and dehydrogenation of several intermediary pigments.
• Sung HW J Thorac Cardiovasc Surg 2001;122:1208-1218
• the simplest component in the blue pigment was a 1:1 adduct.
• genipin reacts spontaneously with an amino acid to form a nitrogen iridoid, which undergoes dehydration to form an aromatic monomer. Dimerization occurs at the second stage, perhaps by means of radical reaction.
• the results suggest that genipin may form intramolecular and intermolecular crosslinks with cyclic structure within collagen fibers in biologic tissue (FIG. 4B) or solidifiable collagen-containing biological material.
• genipin is capable of reacting with a drug having an amine or amino group.
• the crosslinked compound may have collagen linked to the drug via genipin as a bridge crosslinker (FIG. 5).
• Some aspects of the invention related to genipin-crosslinked gelatin as a drug carrier.
• a method for treating tissue of a patient comprising, in combination, loading a solidifiable drug-containing gelatin onto an apparatus or medical device, solidifying the drug-containing gelatin, chemically treating the gelatin with a crosslinking agent, and delivering the medical device to the tissue for treating the tissue.
• Gelatin microspheres haven been widely evaluated as a drug carrier. However, gelatin dissolves rather rapidly in aqueous environments, making the use of gelatin difficult for the production of long-term drug delivery systems. Hsing and associates reported that the degradation rate of the genipin-crosslinked microspheres is significantly increased (J Biomed Mater Res 2003;65A:271-282).
• 70,000 was purchased from Fluka Chemical Co. of Switzerland. The deacetylation degree of the chitosan used was approximately 85%. Subsequently, adjust the chitosan solution to approximately pH 5.5 (right before it becomes gelled) with NaOH. Add in drug(s) of interest into the chitosan solution. While loading the drag-containing chitosan onto a stent, adjust the environment to pH 7 with NaOH to solidify the chitosan onto the stent. The process can be accomplished via a continuous assembly line step by providing gradually increasing pH zones as the device passes by. It is further treated with a crosslinking agent, for example genipin to enhance the biodurability and biocompatibility.
• a crosslinking agent for example genipin
• NOCC a chitosan derived compound that is pH sensitive and can be used in drag delivery.
• This NOCC is water soluble at pH 7.
• the drug containing NOCC can be made harder or more solid-like, if needed, by low pH at about 4. The finished stent slowly releases drug when in the body at a pH around neutral.
• Taxol (paclitaxel) is practically water insoluble as some other drugs of interest in this disclosure. Therefore, first mechanically disperse paclitaxel in a collagen solution at about 4°C. Load the drag containing collagen onto a stent and subsequently raise the temperature to about 37°C to solidify collagen fibers on the stent. The loading step may repeat a plurality of times. Subsequently, crosslink the coated stent with aqueous genipin. The crosslinking on the drag carrier, collagen or chitosan, substantially modify the drug diffusion or eluting rate depending on the degree of crosslinking.
• Example #5 The crosslinking on the drag carrier, collagen or chitosan, substantially modify the drug diffusion or eluting rate depending on the degree of crosslinking.
• Taxol (paclitaxel) is practically water insoluble as some other drugs of interest in this disclosure. Therefore, first mechanically disperse paclitaxel in a collagen solution at about 4°C. Load the drag containing collagen onto a stent and subsequently raise the temperature to about 37°C to solidify collagen fibers on the stent.
• the loading may comprise spray coating, dip coating, plasma coating, painting or other known techniques.
• the loading step may repeat a plurality of times.
• the crosslinking on biological material substantially modify the drug diffusion or eluting rate depending on the degree of crosslinking, wherein the degree of crosslinking of the biological material at a first portion of the stent is different from the degree of crosslinking of the biological material at a second portion or at a third portion of the stent.
• biological material i.e., the drag carrier, collagen or chitosan
• Sirolimus is used as a bioactive agent in this example.
• the loading may comprise spray coating, dip coating, plasma coating, painting or other known techniques.
• the loading step may repeat a plurality of times, wherein each loading step is followed by a crosslinking step, wherein each crosslinking step is either with essentially the same crosslinking degree or with substantially different crosslinking degree.
• the degree of crosslinking of collagen at a first portion of the stent is different from the degree of crosslinking of collagen at a second portion of the stent.
• the resulting sirolimus containing stent with chemically crosslinked collagen is sterilized and packaged for clinical use.
• on preferred sterilization condition may comprise 0.2% peracetic acid and 4% ethanol at room temperature for a period of 1 minute to a few hours.
• Some aspects of the invention provide a medical device, comprising: an apparatus having a surface; a bioactive agent; and biological material loaded onto at least a portion of the surface of the apparatus, the biological material comprising the bioactive agent, wherein the biological material is thereafter crosslinked with a crosslinking agent.
• the medical device of the invention is further sterilized with a condition comprising a sterilant of peracetic acid about 0.1 to 5% and alcohol (preferably ethanol) about 1 to 20% at a temperature of 5 to 50°C for a time of about 1 minute to 5 hours.
• a condition comprising a sterilant of peracetic acid about 0.1 to 5% and alcohol (preferably ethanol) about 1 to 20% at a temperature of 5 to 50°C for a time of about 1 minute to 5 hours.
• a collagen solution is used to dip or spray coat a coronary stent to evaluate the effect of the solution surface tension on coating uniformity.
• a control collagen solution at 10 mg/ml is used to dip coat a stainless steel stent at room temperature. Due to its high surface tension, the collagen tends to cluster or accumulate at the stent comer (where two struts meet) in a thin film. Even after the drying or solidifying step, the collagen at the stent comer is still disproportionately thicker than that at the linear strut portion.
• a surfactant surface tension reducing agent
• 1 ⁇ l octanol is added to the control collagen solution. The resulting collagen coated stent shows less cluster at the stent comer than the control run.
• Some aspects of the invention provide a method to load the solidifiable biological material onto at least a portion of a surface of a medical device comprising reducing surface tension of the biological material, wherein the step of loading comprises dip coating, spray coating, co-extrusion, co-molding, plasma coating, or the like.
• the "biological substance" made of drag-containing biological material of the present invention and or the collagen-drug-genipin compound on a stent can be sterilized before use by lyophilization, ethylene oxide sterilization, or sterilized in a series of ethanol solutions, with a gradual increase in concentration from 20% to 75% over a period of several hours. Finally, the drug-loaded stents are rinsed in sterilized saline solution and packaged.
• the drug carrier, collagen and chitosan may be fully or partially crosslinked. In one aspect of the present invention, a partially crosslinked collagen/chitosan is biodegradable or bioerodible for drag slow-release.
• FIG. 6 shows an illustrated example of a cross-sectional view for a medical device of a vascular stent 1 coated with drag-containing collagen 3 crosslinked with genipin according to the principles of the present invention.
• the stent is generally a mesh type tubular prosthesis made of stainless steel, Nitinol, gold, other metals or plastic material.
• the vascular stent 1 or a stent strut 2 for non-vascular application may further comprise another layer 4 which is slightly different in composition from the drag-containing collagen layer 3.
• the layer 4 may have higher drag loading and higher adhesive properties enabling the layer to be securely coated onto the stent strut 2 or the medical device. Due to the barrier properties of the crosslinked collagen, drag could only slowly diffuse out of the crosslinked matrix.
• Special features for the drug-containing collagen adhesive layer 4 may be characterized by: the layer 4 is securely adhered onto the stent strut; drug is tightly loaded for drug slow release in weeks or months; and collagen is partially crosslinked or fully crosslinked by genipin for stability.
• Special features for the drug-containing collagen layer 3 may be characterized by: the layer 3 is securely adhered to layer 4 and vice versa; and drug may be less tightly loaded or collagen may be crosslinked at a lower degree of crosslinkage for drag slow release in days or weeks.
• Special features for the drag-loaded collagen and/or drug-loaded chitosan crosslinked by genipin may be characterized by: the crosslinked collagen/chitosan with interpenetrated drag enables drag diffusion at a controlled rate; collagen is tissue-friendly and flexible in deployment; and a crosslinked collagen/chitosan material enhances biocompatibility and controlled biodegradability.
• the whole process for manufacturing a collagen-drug-genipin or chitosan-drug-genipin compound can be automated in an environmentally controlled facility. Sufficient amount of collagen or drug could be loaded to the exterior side of the stent strut for restenosis mitigation or other therapeutic effects.
• One preferred aspect of the invention provides a method for treating a target tissue of a patient comprising: (a) crosslinking a biological material with a crosslinking agent; (b) mixing a bioactive agent with the biological material; (c) loading the biological material onto at least a portion of a surface of a medical device or an apparatus; and (d) delivering the medical device to the target tissue and releasing the bioactive agent for treating the target tissue.
• the method comprises a step of solidifying the biological material before the delivering step.
• the method further comprises a step of chemically linking the bioactive agent with the biological material through a crosslinker before the solidifying step, wherein the bioactive agent comprises at least a crosslinkable functional group.
• the "drag” further comprises bioactive agents or materials which may be used in the present invention include, for example, pharmaceutically active compounds, proteins, oligonucleotides, ribozymes, anti-sense genes, DNA compacting agents, gene/vector systems (i.e., anything that allows for the uptake and expression of nucleic acids), nucleic acids (including, for example, naked DNA, cDNA, RNA, DNA, cDNA, or RNA in a non-infectious vector or in a viral vector which may have attached peptide targeting sequences; antisense nucleic acid (RNA or DNA); and DNA chimeras which include gene sequences and encoding for ferry proteins such as membrane translocating sequences ("MTS") and herpes simplex virus-1 (“VP22”)), and viral, liposomes and cationic polymers that are selected from a number of types depending on the desired application, including retrovirus, adenovirus, adeno-associated virus, her
• bioactive agents or materials include, for example, pharmaceutically
• biologically active solutes include anti-thrombogenic agents such as heparin, heparin derivatives, urokinase, PPACK (dextrophenylalanine proline arginine chloromethylketone), rapamycin, probucol, and verapamil; angiogenic and anti-angiogenic agents; anti-proliferative agents such as enoxaparin, angiopeptin, or monoclonal antibodies capable of blocking smooth muscle cell proliferation, hiradin, and acetylsalicylic acid; anti-inflammatory agents such as dexamethasone, prednisolone, corticosterone, budesonide, estrogen, sulfasalazine, and mesalarnine; antineoplastic/antiproliferative/anti-mitotic agents such as paclitaxel, 5-fluorouracil, cisplatin, vinblastine, vincristine, epothilones, endo
• U.S. Pat. No. 6,423,682 issued on July 23, 2002 and U.S. Pat. No. 6,485,920, issued on November 26, 2002, the entire contents of both of which are incorporated herein by reference, disclose the compositions of novel human growth factor antagonist proteins and active variants thereof, isolated polynucleotides encoding such polypeptides, including recombinant DNA molecules, cloned genes or degenerate variants thereof, especially naturally occurring variants such as allelic variants, antisense polynucleotide molecules, and antibodies that specifically recognize one or more epitopes present on such polypeptides, as well as hybridomas producing such antibodies function of mitochondria and toxic substances synthesized as a metabolic byproduct within mitochondria of cells.
• Some aspects of the present invention provide a device comprising solidifiable bioactive agent-containing biological material loaded onto at least a portion of the surface of the device, followed by being crosslinked with a crosslinking agent, wherein the bioactive agent comprises at least one of the above-cited genes.
• CD39 (cluster of differentiation 39) is a cell-surface molecule recognized by a "cluster" of monoclonal antibodies that can be used to identify the lineage or stage of differentiation of lymphocytes and thus to distinguish one class of lymphocytes from another.
• Some aspects of the present invention provide a device comprising solidifiable bioactive agent-containing biological material loaded onto at least a portion of the surface of the device, followed by being crosslinked with a crosslinking agent, wherein the bioactive agent comprises the above-cited human CD39-like protein polynucleotides or the like.
• the patent discloses methods of delivering a selected agent into a damaged target cell for diagnosis and therapy, wherein the conjugate comprises a biological agent selected from the group consisting of fibroblastic growth factor- ⁇ , angiogenic factors, high energy substrates for the myocardium, antioxidants, cytokines and contrast agents.
• Some aspects of the present invention provide a device comprising solidifiable bioactive agent-containing biological material loaded onto at least a portion of the surface of the device, followed by being crosslinked with a crosslinking agent, wherein the bioactive agent comprises the above-cited fibroblastic growth factor- ⁇ , angiogenic factors, high energy substrates for the myocardium, antioxidants, cytokines and the like.
• the anti-angiogenic polypeptides include at least kringles 1-3 of plasminogen.
• the patent '784 also provides methods of using the polypeptides and nucleic acids for inhibiting angiogenesis and other conditions characterized by undesirable endothelial cell proliferation.
• Angiostatin which is an angiogenesis inhibitor, is a naturally occurring internal cleavage product of plasminogen, wherein human plasminogen has five characteristic protein domains called "kringle structures".
• Some aspects of the present invention provide a device comprising solidifiable bioactive agent-containing biological material loaded onto at least a portion of the surface of the device, followed by being crosslinked with a crosslinking agent, wherein the bioactive agent comprises the above-cited anti-angiogenic polypeptides, angiostatin, angiogenesis inhibitor, and the like.
• U.S. Pat. No. 6,436,703 issued on August 20, 2002, the entire contents of which are incorporated herein by reference, discloses a method and compositions comprising novel isolated polypeptides, novel isolated polynucleotides encoding such polypeptides, including recombinant DNA molecules, cloned genes or degenerate variants thereof, especially naturally occurring variants such as allelic variants, antisense polynucleotide molecules, and antibodies that specifically recognize one or more epitopes present on such polypeptides, as well as hybridomas producing such antibodies.
• compositions in '703 additionally include vectors, including expression vectors, containing the polynucleotides of the invention, cells genetically engineered to contain such polynucleotides and cells genetically engineered to express such polynucleotides.
• vectors including expression vectors, containing the polynucleotides of the invention, cells genetically engineered to contain such polynucleotides and cells genetically engineered to express such polynucleotides.
• U.S. Pat. No. 6,451,764 discloses a method of treating vascular tissue and promoting angiogenesis in a mammal comprising administering to the mammal an effective amount of the composition comprising VRP (vascular endothelial growth factor-related protein).
• VRP vascular endothelial growth factor-related protein
• the disclosure '764 further provides a method for treating trauma affecting the vascular endothelium comprising administering to a mammal suffering from the trauma an effective amount of the composition containing the VRP, or a method for treating a dysfunctional state characterized by lack of activation or lack of inhibition of a receptor for VRP in a mammal.
• Some aspects of the present invention provide a device comprising solidifiable bioactive agent-containing biological material loaded onto at least a portion of the surface of the device, followed by being crosslinked with a crosslinking agent, wherein the bioactive agent comprises the above-cited inhibitors or receptors for vascular endothelial growth factor-related protein and the like.
• a novel and unobvious process for making a biological substance comprising an illustrative collagen-drug-genipin compound or chitosan-drug-genipin compound for drag slow release has been disclosed for tissue treatment applications.
• the process comprises, in combination, mixing a drag with a solidifiable biological material, chemically treating the biological material and/or the drug with a crosslinking agent, loading the solidifiable drug-containing biological material onto a medical device, and solidifying the drug-containing biological material.
• the resulting biological substance is generally characterized with reduced antigenicity, reduced immunogenicity, and reduced enzymatic degradation and capable of drag slow-release.

Landscapes

• Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Epidemiology (AREA)
• Veterinary Medicine (AREA)
• Public Health (AREA)
• General Health & Medical Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• Chemical & Material Sciences (AREA)
• Medicinal Chemistry (AREA)
• Biomedical Technology (AREA)
• Molecular Biology (AREA)
• Engineering & Computer Science (AREA)
• Vascular Medicine (AREA)
• Surgery (AREA)
• Heart & Thoracic Surgery (AREA)
• Dermatology (AREA)
• Oral & Maxillofacial Surgery (AREA)
• Transplantation (AREA)
• Materials For Medical Uses (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=31494298

Family Applications (1)

Country Status (4)

Families Citing this family (22)

Citations (3)

Family Cites Families (1)

• 2003
  • 2003-08-01 WO PCT/US2003/024445 patent/WO2004012676A2/en active Application Filing
  • 2003-08-01 JP JP2004526437A patent/JP2006500975A/ja not_active Withdrawn
  • 2003-08-01 AU AU2003257179A patent/AU2003257179A1/en not_active Abandoned
  • 2003-08-01 EP EP03767189A patent/EP1545505A4/en not_active Withdrawn

Patent Citations (3)

Non-Patent Citations (3)

Also Published As

Similar Documents

Legal Events