Shellac and paclitaxel coated catheter balloons
11167065 · 2021-11-09
Assignee
Inventors
Cpc classification
A61L29/16
HUMAN NECESSITIES
A61L2300/416
HUMAN NECESSITIES
International classification
Abstract
The present invention relates to a method for coating catheter balloons with the pharmacological agent paclitaxel and the biological and biodegradable polymer composition shellac and optionally further components. Moreover the present invention relates to paclitaxel and shellac coated catheter balloons obtained according to the coating methods disclosed herein as well as the use of such coated catheter balloons for the short time release of the pharmaceutically active agent paclitaxel for prophylaxis and treatment of restenosis especially restenosis caused by angioplasty. The coated catheter balloons can be used alone or in combination with a coated or uncoated stent crimped on the catheter balloon before or after the coating with shellac and paclitaxel.
Claims
1. A method for coating a catheter balloon comprising the following steps: I) providing an uncoated catheter balloon; and IIA) providing a solution of paclitaxel and shellac; or IIB) providing a solution of paclitaxel and providing a solution of shellac; and IIIA) coating the surface of the catheter balloon with the solution of paclitaxel and shellac; or IIIB) coating the surface of the catheter balloon with the solution of paclitaxel and subsequently with the solution of shellac or coating the surface of the catheter balloon with the solution of shellac and subsequently with the solution of paclitaxel; IV) drying the coated catheter balloon.
2. The method according to claim 1, wherein the solution of paclitaxel and the solution of shellac or the solution of paclitaxel and shellac are prepared in acetone, ethyl acetate, ethanol, methanol, DMSO, THF, chloroform, methylene chloride or mixtures of the afore-mentioned solvents.
3. The method according to claim 2, wherein the solution of paclitaxel and shellac IIA) or the solution of paclitaxel IIB) has a paclitaxel content that is between 10 to 500 μg of paclitaxel per 1 ml solution.
4. The method according to claim 1, wherein the total surface loading with paclitaxel and shellac of the catheter balloon is between 1 μg/mm.sup.2 and 12 μg/mm.sup.2 and/or wherein the total surface loading with paclitaxel of the catheter balloon is between 0.5 μg/mm.sup.2 and 6 μg/mm.sup.2.
5. The method according to claim 1 further comprising the step of protecting any parts of the balloon catheter which should not be coated with a removable protection sheet.
6. The method according to claim 1 further comprising the step V): V) Protecting the coated catheter balloon with a removable protection cover.
7. The method according to claim 1, wherein at least one carrier substance is added to the solution of paclitaxel and shellac IIA), or the solution of paclitaxel IIB).
8. The method according to claim 7, wherein the at least one carrier substance is selected from the group consisting of: parylene C, parylene D, parylene N, parylene F, polyvalerolactones, poly-ε-decalactone, polylactonic acid, polyglycolic acid, polylactides, polyglycolides, copolymers of the polylactides and polyglycolides, poly ε-caprolactone, polyhydroxybutyric acid, polyhydroxybutyrates, polyhydroxyvalerates, polyhydroxybutyrate-co-valerate, poly(1,4-dioxane-2,3-dione), poly(1,3-dioxane-2-one), poly-para-dioxanone, polyanhydrides, polymaleic acid anhydride, polyhydroxymethacrylates, fibrin, polycyanoacrylate, polycaprolactone dimethylacrylates, poly-B-maleic acid, polycaprolactone butyl acrylates, multiblock polymers from oligocaprolactonedioles and oligodioxanonedioles, polyether ester multiblock polymers from PEG and poly(butylene terephthalate), polypivotolactones, polyglycolic acid trimethyl carbonates, polycaprolactone glycolides, poly(γ-ethyl glutamate), poly(DTH-iminocarbonate), poly(DTE-co-DT-carbonate), poly(bisphenol A-iminocarbonate), polyorthoesters, polyglycolic acid trimethyl-carbonate, polytrimethyl carbonates, polyiminocarbonates, poly(N-vinyl)-pyrrolidone, polyvinyl alcohols, polyester amides, glycolized polyesters, polyphosphoesters, polyphosphazenes, poly[p-carboxyphenoxy)propane], polyhydroxy pentanoi c acid, polyanhydrides, polyethylene oxide propylene oxide soft polyurethanes, polyurethanes having amino acid residues in the backbone, polyether esters, polyethylene oxide, polyalkene oxalates, polyorthoesters as well as their copolymers, lipids, carrageenans, fibrinogen, starch, collagen, polyamino acids, synthetic polyamino acids, zein, polyhydroxyalkanoates, pectic acid, actinic acid, carboxymethyl sulfate, albumin, hyaluronic acid, chitosan and derivatives thereof, heparan sulfates and derivatives thereof, heparins, chondroitin sulfate, dextran, B-cyclodextrins, copolymers with PEG and polypropylene glycol, gum arabic, guar, gelatin, collagen N-hydroxysuccinimide, phospholipids, polyacrylic acid, polyacrylates, polymethyl methacrylate, polybutyl methacrylate, polyacrylamide, polyacrylonitriles, polyamides, polyetheramides, polyethylene amine, polyimides, polycarbonates, polycarbourethanes, polyvinyl ketones, polyvinyl halogenides, polyvinylidene halogenides, polyvinyl ethers, polyisobutylenes, polyvinyl aromatics, polyvinyl esters, polyvinyl pyrrolidones, polyoxymethylene, polytetramethylene oxide, polyethylene, polypropylene, polytetrafluoroethylene, polyurethanes, polyether urethanes, silicone polyether urethanes, silicone polyurethanes, silicone polycarbonate urethanes, polyolefin elastomers, EPDM gums, fluorosilicones, carboxymethyl chitosans, polyaryletheretherketones, polyetheretherketones, polyethylene terephthalate, polyvalerates, carboxymethylcellulose, cellulose, rayon, rayon triacetates, cellulose nitrates, cellulose acetates, hydroxyethyl cellulose, cellulose butyrates, cellulose acetate butyrates, ethyl vinyl acetate copolymers, polysulfones, epoxy resins, ABS resins, silicones, polysiloxanes, polydimethylsiloxanes, polyvinyl halogens and copolymers, cellulose ethers, cellulose triacetates, chitosans and copolymers of chitosans, and/or mixtures of the aforementioned polymers.
9. The method according to claim 1, wherein steps IIIA) or IIIB) and IV) are repeated several times.
10. The method according to claim 1, wherein the solution of paclitaxel and shellac IIA), or the solution of paclitaxel IIB), has a paclitaxel content that is between 10 to 500 μg of paclitaxel per 1 ml solution.
11. The method according to claim 1, wherein the solution of paclitaxel and shellac IIA), or the solution of paclitaxel IIB), is applied by one or more from the group consisting of spray coating, brush coating, dip coating, vapour deposition or pipetting.
12. The method according to claim 1, wherein the catheter balloon consists of a material or a mixture of materials, wherein the material or the mixture of materials is selected from the following group of materials consisting of: parylene C, parylene D, parylene N, parylene F, polyvalerolactones, poly-ε-decalactone, polylactonic acid, polyglycolic acid, polylactides, polyglycolides, copolymers of the polylactides and polyglycolides, poly ε-caprolactone, polyhydroxybutyric acid, polyhydroxybutyrates, polyhydroxyvalerates, polyhydroxybutyrate-co-valerate, poly(1,4-dioxane-2,3-dione), poly(1,3-dioxane-2-one), poly-para-dioxanone, polyanhydrides, polymaleic acid anhydride, polyhydroxymethacrylates, fibrin, polycyanoacrylate, polycaprolactone dimethylacrylates, poly-B-maleic acid, polycaprolactone butyl acrylates, multiblock polymers from oligocaprolactonedioles and oligodioxanonedioles, polyether ester multiblock polymers from PEG and poly(butylene terephthalate), polypivotolactones, polyglycolic acid trimethyl carbonates, polycaprolactone glycolides, poly(γ-ethyl glutamate) poly(DTH-iminocarbonate), poly(DTE-co-DT-carbonate), poly(bisphenol A-iminocarbonate), polyorthoesters, polyglycolic acid trimethyl-carbonate, polytrimethyl carbonates, polyiminocarbonates, poly(N-vinyl)-pyrrolidone, polyvinyl alcohols, polyester amides, glycolized polyesters, polyphosphoesters, polyphosphazenes, poly[p-carboxyphenoxy)propane], polyhydroxy pentanoi c acid, polyanhydrides, polyethylene oxide propylene oxide, soft polyurethanes, polyurethanes having amino acid residues in the backbone, polyether ester, polyethylene oxide, polyalkene oxalates, polyorthoesters as well as their copolymers, lipids, carrageenans, fibrinogen, starch, collagen, polyamino acids, synthetic polyamino acids, zein, polyhydroxyalkanoates, pectic acid, actinic acid, carboxymethyl sulfate, albumin, hyaluronic acid, chitosan and derivatives thereof, heparan sulfates and derivatives thereof, heparins, chondroitin sulfate, dextran, β-cyclodextrins, copolymers with PEG and polypropylene glycol, gum arabic, guar, gelatine, collagen N-hydroxysuccinimide, phospholipids, polyacrylic acid, polyacrylates, polymethyl methacrylate, polybutyl methacrylate, polyacrylamide, polyacrylonitriles, polyamides, polyetheramides, polyethylene amine, polyimides, polycarbonates, polycarbourethanes, polyvinyl ketones, polyvinyl halogenides, polyvinylidene halogenides, polyvinyl ethers, polyisobutylenes, polyvinyl aromatics, polyvinyl esters, polyvinyl pyrrolidones, polyoxymethylene, polytetramethylene oxide, polyethylene, polypropylene, polytetrafluoroethylene, polyurethanes, polyether urethanes, silicone polyether urethanes, silicone polyurethanes, silicone polycarbonate urethanes, polyolefin elastomers, EPDM gums, fluorosilicones, carboxymethyl chitosans, polyaryletheretherketones, polyetheretherketones, polyethylene terephthalate, polyvalerates, carboxymethylcellulose, cellulose, rayon, rayon tri acetates, cellulose nitrates, cellulose acetates, hydroxyethyl cellulose, cellulose butyrates, cellulose acetate butyrates, ethyl vinyl acetate copolymers, polysulfones, epoxy resins, ABS resins, silicones, polysiloxanes, polydimethylsiloxanes, polyvinyl halogens and copolymers, cellulose ethers, cellulose triacetates, chitosans as well as copolymers of chitosans, and/or mixtures of the aforementioned polymers.
13. The method according to claim 1, wherein an additional active agent is added to the paclitaxel and/or shellac containing solution and wherein said additional active agent is selected from the group consisting of: abciximab, acemetacin, acetylvismione B, aclarubicin, ademetionine, adriamycin, aescin, afromosone, akagerine, aldesleukin, amidorone, aminoglutethimide, amsacrine, anakinra, anastrozole, anemonin, anopterine, antimycotics antithrombotics, apocymarin, argatroban, aristolactam-AII, aristolochic acid, ascomycin, asparaginase, aspirin, atorvastatin, auranofin, azathioprine, azithromycin, baccatin, bafilomycin, basiliximab, bendamustine, benzocaine, berberine, betulin, betulinic acid, bilobol, bisparthenolidine, bleomycin, combrestatin, Boswellic acids and derivatives thereof, bruceanol A, B and C, bryophyllin A, busulfan, antithrombin, bivalirudin, cadherins, camptothecin, capecitabine, o-carbamoyl-phenoxyacetic acid, carboplatin, carmustine, celecoxib, cepharanthin, cerivastatin, CETP inhibitors, chlorambucil, chloroquine phosphate, cicutoxin, ciprofloxacin, cisplatin, cladribine, clarithromycin, colchicine, concanamycin, a warfarin, C-type natriuretic peptide, cudraisoflavone A, curcumin, cyclophosphamide, ciclosporin A, cytarabine, dacarbazine, daclizumab, dactinomycin, dapsone, daunorubicin, diclofenac, 1,11-dimethoxycanthin-6-one, docetaxel, doxorubicin, daunamycin, epirubicin, epothilone A and B, erythromycin, estramustine, etoposide, everolimus, filgrastim, fluroblastin, fluvastatin, fludarabine, fludarabine-5′-dihydrogen phosphate, fluorouracil, folimycin, fosfestrol, gemcitabine, ghalakinoside, ginkgol, ginkgolic acid, glycoside 1a, 4-hydroxyoxycyclo phosphamide, idarubicin, ifosfamide, josamycin, lapachol, lomustine, lovastatin, melphalan, midecamycin, mitoxantrone, nimustine, pitavastatin, pravastatin, procarbazine, mitomycin, methotrexate, mercaptopurine, thioguanine, oxaliplatin, irinotecan, topotecan, hydroxycarbamide, miltefosine, pentostatin, pegaspargase, exemestane, letrozole, formestane, mycophenolate mofetil, β-lapachone, podophyllotoxin, podophyllic acid-2-ethyl hydrazide, molgramostim, peginterferon α-2b, lenograstim, macrogol, selectin, cytokinin inhibitors, COX-2 inhibitor, angiopeptin, monoclonal antibodies inhibiting muscle cell proliferation, bFGF antagonists, probucol, prostaglandins, 1-hydroxy-11-methoxycanthin-6-one, scopoletin, NO donors, pentaerythrityl tetranitrate and sydnoimines, S-nitroso derivatives, tamoxifen, staurosporine, β-estradiol, α-estradiol, estriol, estrone, ethinyl estradiol, medroxyprogesterone, estradiol cypionates, estradiol benzoates, tranilast, kamebakaurin and other terpenoids used in cancer therapy, verapamil, tyrosine kinase inhibitors, paclitaxel and derivatives thereof, 6-a-hydroxy-paclitaxel, docetaxel, mofebutazone, lonazolac, lidocaine, ketoprofen, mefenamic acid, piroxicam, meloxicam, penicillamine, hydroxychloroquine, sodium aurothiomalate, oxaceprol, β-sitosterol, myrtecaine, polidocanol, nonivamide, levomenthol, ellipticine, N-(Pyridin-4-yl)-[1-(4-chlorobenzyl)-indol-3-yl]-glyoxyl amide, N-methy-N-deacetylcolcicine, cytochalasin A-E, indanocine, nocodazole, bacitracin, vitronectin receptor antagonists, azelastine, guanidyl cyclase stimulator, tissue inhibitor of metal proteinase-1 and 2, free nucleic acids, nucleic acids incorporated into virus transmitters, DNA and RNA fragments, plasminogen activator inhibitor 1, plasminogen activator inhibitor 2, antisense oligonucleotides, VEGF inhibitors, IGF-1, active agents from the group of antibiotics, cefadroxil, cefazolin, cefaclor, cefoxitin, tobramycin, gentamicin, penicillins, dicloxacillin, oxacillin, sulfonamides, metronidazole, enoxaparin, heparin, hirudin, PPACK, protamine, prourokinase, streptokinase, warfarin, urokinase, vasodilators, dipyramidole, trapidil, nitroprussides, PDGF antagonists, triazolopyrimidine, seramin, ACE inhibitors, captopril, cilazapril, lisinopril, enalapril, losartan, thioprotease inhibitors, prostacyclin, vapiprost, interferon α, β and γ, histamine antagonists, serotonin blockers, apoptosis inhibitors, apoptosis regulators, halofuginone, nifedipine, tocopherol, tranilast, molsidomine, tea polyphenols, epicatechin gallate, epigallocatechin gallate, leflunomide, etanercept, sulfasalazine, tetracycline, triamcinolone, mutamycin, procainimide, retinoic acid, quinidine, disopyrimide, flecainide, propafenone, sotalol, natural and synthetically obtained steroids, bryophyllin A, inotodiol, maquiroside A, ghalakinoside, mansonine, strebloside, hydrocortisone, betamethasone, dexamethasone, non-steroidal substances, fenoprofen, ibuprofen, indomethacin, naproxen, phenylbutazone, antiviral agents, acyclovir, ganciclovir zidovudine, clotrimazole, flucytosine, griseofulvin, ketoconazole, miconazole, nystatin, terbinafine, antiprotozoal agents, chloroquine, mefloquine, quinine, natural terpenoids, hippocaesculin, barringtogenol-C21-angelate, 14-dehydroagrostistachin, agroskerin, agrostistachin, 17-hydroxyagrostistachin, ovatodiolids, 4,7-oxycycloanisomelic acid baccharinoids B 1, B2, B3 and B7, tubeimoside, bruceantinoside C, yadanziosides N and P, isodeoxyelephantopin, tomenphantopin A and B, coronarin A, B C and D, ursolic acid, hyptatic acid A, iso-iridogermanal, maytenfoliol, effusantin A, excisanin A and B, longikaurin B, sculponeatin C, kamebaunin, leukamenin A and B, 13,18-dehydro-6-alpha-senecioyloxychaparrin, taxamairin A and B, regenilol, triptolide, cymarin, hydroxyanopterine, protoanemonin, cheliburin chloride, sinococuline A and B, dihydronitidine, nitidine chloride, 12-β-hydroxypregnadien-3,20-dione, helenalin, indicine, indicine-N-oxide, lasiocarpine, inotodiol, podophyllotoxin, justicidin A and B, larreatin, malloterin, mallotochromanol, isobutyrylmallotochromanol, marchantin A, maytansin, lycoridicin, margetine, pancratistatin, liriodenine, oxoushinsunine, periplocoside A, deoxypsorospermin, psychorubin, ricin A, sanguinarine, manwu wheat acid, methylsorbifolin, chromones of spathelia, stizophyllin, dihydrousambaraensine, hydroxyusambarine, strychnopentamine, strychnophylline, usambarine, usambarensine, liriodenine, daphnoretin, lariciresinol, methoxylariciresinol, syringaresinol, sirolimus, somatostatin, tacrolimus, roxithromycin, troleandomycin, simvastatin, rosuvastatin, vinblastine, vincristine, vindesine, teniposide, vinorelbine, trofosfamide, treosulfan, temozolomide, thiotepa, tretinoin, spiramycin, umbelliferone, desacetylvismione A, vismione A and B, and zeorin.
Description
EXAMPLES
Example 1a
(1) A commercially available dilatation catheter with expandable balloon composed of a polyamide is provided.
(2) The surface of the catheter balloon is roughened in the range of nanometers to micrometers by means of sand blasting.
(3) Paclitaxel (commercially available from Sigma, Fermentek, BC Biotech or Arianna International) is dissolved in acetone together with shellac at a concentration of 50 μg paclitaxel and 100 μg shellac per ml of acetone.
(4) The solution of paclitaxel and shellac in acetone is sprayed onto the catheter balloon and is repeated three further times after drying the coated balloon surface. The drying process is performed at room temperature and atmospheric pressure.
(5) After the final coating step the catheter balloon is dried under reduced pressure and sterilized with ethylene oxide. Than the coated balloon surface is protected with a protection cover and packed for shipping or storing.
Example 1b
(6) A commercially available dilatation catheter with expandable balloon composed of a polyamide is provided.
(7) Paclitaxel (commercially available from Sigma, Fermentek, BC Biotech or Arianna International) is dissolved in ethanol together with shellac at a concentration of 50 μg paclitaxel and 100 μg shellac per ml of ethanol.
(8) The solution of paclitaxel and shellac in ethanol is applied onto the catheter balloon with a micropipette.
(9) After the coating step the catheter balloon is dried under reduced pressure and sterilized with ethylene oxide. Than the coated balloon surface is protected with a protection cover and packed for shipping or storing.
Example 1c
(10) A commercially available dilatation catheter with expandable balloon composed of a polyamide is provided.
(11) Paclitaxel (commercially available from Sigma, Fermentek, BC Biotech or Arianna International) is dissolved in ethanol together with shellac at a concentration of 50 μg paclitaxel and 100 μg shellac per ml of ethanol.
(12) The solution of paclitaxel and shellac in ethanol is applied onto the catheter balloon by dipping (dip-coating) the catheter balloon in the solution.
(13) After the coating step the catheter balloon is dried under reduced pressure and sterilized with ethylene oxide. Than the coated balloon surface is protected with a protection cover and packed for shipping or storing.
Example 2
(14) A multifold balloon such as described, for example, in WO 2004/028582 A1, WO 94/23787 A1 or WO 03/059430 A1 is provided. The multifold balloon is provided with a total of 5 folds enclosing a cavity when the balloon is in compressed state and bending outward when it is in expanded state so that the balloon in its expanded state has an essentially tube-like shape.
(15) The multifold balloon is expanded and then its surface is roughened by means of a so called “chemical polishing” process, wherein a suspension of fine particles, preferably in the range of micrometers, is used in said process and said suspension is rubbed onto the surface of the expanded catheter balloon such that a roughened surface is created.
(16) A solution of 80 μg of paclitaxel in 1.0 ml of ethyl acetate and a solution of 100 μg shellac in THF is provided.
(17) The roughened expanded catheter balloon is dipped several times into said solution of paclitaxel in ethyl acetate and dried at room temperature and atmospheric pressure after each dipping.
(18) Than, the shellac solution in THF is filled into a pipette and applied onto the dry paclitaxel coating on the balloon surface.
(19) The total paclitaxel load on the balloon surface is between 1 μg to 5 μg of paclitaxel per mm.sup.2 of coated balloon surface.
(20) After sterilization, the balloon is provided with a protective sheath intended to protect the active agent on the coated dilatable catheter balloon during transport and storage which sheath is removed prior to the insertion of the catheter by the cardiologist.
Example 3
(21) A commercially available dilatation catheter with expandable balloon made of a polymer is provided. The catheter balloon consists of a block copolymer of polyamide, polyether and polyester or of polyurethane, a polyester or a polyolefin. The balloon surface is smooth and not textured and without channels or cavities.
(22) A solution of 70 μg of paclitaxel and 50 μg of shellac in 1.0 ml of ethanol having a water content of about 3 percent by volume is prepared and applied onto the horizontal area of the surface of the catheter balloon by brushing or spattering.
(23) Subsequently, the catheter balloon is thoroughly dried and sterilized with ethylene oxide. After sterilization, the balloon is provided with a protective sheath intended to protect the active agent on the coated dilatable catheter balloon during transport and storage which sheath is removed prior to the insertion of the catheter by the cardiologist.
Example 4
(24) A coated catheter balloon is manufactured having a paclitaxel coating of 3 ug paclitaxel/mm.sup.2 balloon surface.
(25) The below described technology is used for the coating of PTCA balloon catheter for application in coronary stenosis. The coating consists of a degradable, drug eluting shellac-paclitaxel composite with a surface loading of normally totaling 4 to 8 μg/mm.sup.2 whereas the mass portion of paclitaxel component is preferably nominal 1 to 3 μg/mm.sup.2. This coating layer is applied with intention to release an effectual portion of paclitaxel to the local wall of the artery at the dilated stenosis. Within short term release of paclitaxel during balloon dilatation the convenient effect of the mitosis inhibitor shall combined with fast release of biological biodegradable carrier shellac.
(26) Process Description
(27) 1 General Handling:
(28) The complete process of quality assurance, coating and packaging is done under cleanroom similar conditions by using a cytostatic safety cabinet and a laminar flow box.
(29) 2 Coating Dilution:
(30) The coating dilution is a mixture of paclitaxel and shellac in proportion 1:1 in a necessary portion of ethyl alcohol. All raw materials undergo an incoming inspection and are defined be raw material specification.
(31) 3 Coating Process:
(32) Before coating process the coating quantity must be calculated. The coating quantity is the product of balloon surface and the specific load of 3 μg/mm.sup.2. After unpacking of the catheter the protection tube must be removed. In cytostatic safety cabinet the catheter will inserted into the working tube and adjusted. After removal of the protection cover the catheter must be inserted to the coating device. Then the catheter would be fixed by a pneumatic actuator and the visual inspection is executed by a microscopical camera. Afterwards the required quantity of coating dilution is applied by a pipette to the distribution rack. The distribution rack is working under influence of a warm air blower until the dilution is distributed at the balloon surface. After evaporation of the ethyl alcohol the coating is fixed with high adhesion at the surface. The postprocessing is done by a drying step with warm air and the visual surface control by microscopical camera.
(33) The coating process is now completed and the catheter must be removed from fixation, the balloon will protected by a protection cover and inserted to the protection tube. The storage of coated devices before packaging is done in a laminar flowbox.
(34) The paclitaxel-shellac coating process is exclusively executed with calibrated and qualified coating equipment and certified raw materials.
(35) The total load of paclitaxel and shellac per mm.sup.2 balloon surface is 5 μg/mm.sup.2, while the content of paclitaxel per mm.sup.2 balloon surface is 1 μg/mm.sup.2.
(36) 4 Packaging Process
(37) The coated PTCA catheters are packaged under laminar flowbox into sterile pouches which are appropriate for ethylene oxide sterilisation. An ethylene oxide indicator is added to every pouch. Afterwards the pouches are labelled in accordance with the order. All following packaging steps are severed from the production area. The EtO sterilization (ethylene oxide sterilization) process is supported by a sterilisation validation.
(38) 5 Quality Controls
(39) Both raw materials for coating undergo incoming inspection and will ordered and accepted with certificate. Incoming products will strictly controlled regarding stain, surface defects and scratches by optical inspection. Before and after paclitaxel-shellac coating there is a careful visual surface quality control by microscopical camera. For determination of shellac-paclitaxel coating mass per balloon a differential weight at a dummy sample is installed. This would be done for every new type of balloon size and/or new coating parent solution. The shellac-paclitaxel loading per surface is substantiated by a process validation.
Example 5: Biological Tests
(40) Methods:
(41) 1. Location of the Balloon Dilatation:
(42) The locations of the balloon dilatation are presented in Table 1.
(43) 2. Porcine Coronary Balloon Dilatation Model:
(44) Seven domestic pigs (weight 18-30 kg) were sedated with 12 mg/kg ketamine hydrochloride, 1 mg/kg xylazine and 0.04 mg/kg atropine after overnight fasting. Loading dose of clopidogrel (300 mg per os) and aspirin (250 mg per os) were administered 24 h prior to procedure. Following intratracheal intubation, arteriotomies of the right femoral arteries were performed under sterile conditions and a 6 F introduction sheath was inserted.
(45) After administration of 200 IU/kg of heparin sodium, selective angiography of the left and right coronary arteries was performed and guide wire was introduced into the distal part of the left anterior descending coronary artery (LAD), left circumflex (LCx) and right coronary arteries (RCA). A paclitaxel-shellac coated balloon catheter (3.0 mm in diameter, 20 mm of length) (Eurocor, Bonn Germany) was inserted into the LAD and LCx after the origin of the first major diagonal branch or the proximal RCA. The paclitaxel-shellac coated balloon was inflated for 30 sec with 709.27-810.59 kPa (7-8 atm), followed by deflation of the balloon, then repeated inflation for 30 sec with 709.27-810.59 kPa (7-8 atm) was performed. Coronary angiography confirmed the occlusion with complete contact of the balloon with the vessel wall in each dilatation. Additionally, in 2 LCx arteries and 1 LAD with relative large obtuse marginalis or diagonal branch (vessel diameter at least 2 mm on the quantitative angiography), bifurcation intervention was performed: first the main branch (MB) was dilated with the inventive paclitaxel-shellac coated balloon 2×30 sec 709.27-810.59 kPa (7-8 atm), then the side branch (SB) with the inventive paclitaxel-shellac coated balloon (2×30 sex, 607.94-810.59 kPa (6-8 atm)) followed by kissing balloon dilatation with the same inventive paclitaxel-shellac coated balloons.
(46) TABLE-US-00001 TABLE 1 Location of the paclitaxel-shellac coated balloon dilatation. ID (survival LAD LCX RCA RCA time) MB SB MB SB Proximal Distal PS-balloon-1 PS-balloon PS-balloon PS-balloon PS-balloon (12 h) 3.0/20 mm 3.0/20 mm 2.5/20 mm 3.0/20 mm PS-balloon-2 PS-balloon PS-balloon PS-balloon PS-balloon PS-balloon PS-balloon (12 h) 3.0/20 mm 2.5/20 mm 3.0/20 mm 2.5/20 mm 3.0/20 mm 3.0/20 mm PS-balloon-3 PS-balloon PS-balloon PS-balloon (<1 h) 3.0/20 mm 3.0/20 mm 2.5/20 mm (mid-LAD) PS-balloon 3.0/20 mm (prox LAD) PS-balloon-4 PS-balloon PS-balloon PS-balloon PS-balloon PS-balloon PS-balloon (<1 h) 3.0/20 mm 2.5/20 mm 3.0/20 mm 2.5/20 mm 3.0/20 mm 3.0/20 mm EFFICACY STUDY PS-balloon-5 PS-balloon PS-balloon (2 weeks) 3.0/20 mm 3.0/20 mm (prox LAD) (prox LCx) Allegro Allegro 2.5/20 mm 2.5/20 mm (dist LAD) (dist LCx) PS-balloon-6 PS-balloon PS-balloon (2 weeks) 3.0/20 mm 3.0/20 mm (prox LAD) (prox LCx) Allegro Allegro 2.5/20 mm 2.5/20 mm (dist LAD) (dist LCx) PS-balloon-7 PS-balloon PS-balloon (2 weeks) 3.0/20 mm 3.0/20 mm (prox LAD) (prox LCx) Expleo Allegro 3.0/20 mm 2.5/20 mm (dist LAD) (dist LCx)
(47) The term PS-balloon refer to the inventive paclitaxel-shellac coated catheter balloon
(48) LAD: left anterior descending coronary artery,
(49) LCx: left circumflex coronary artery, RCA: right coronary artery
(50) The last 3 pigs (PS-balloon 5-7) underwent PS-balloon dilatation of the proximal LAD and LCx arteries (2×30 sec), and distal part of the LAD and LCX were dilated with non-coated balloons. The femoral arteriotomy was repaired and the pigs were allowed to recover.
(51) Euthanasia was performed with saturated potassium chloride approximately 5 min after the last balloon dilatation (PS-balloon-3 and 4) and 12 h later (PS-balloon-1 and 2). Three pigs (PS-balloon-5, 6 and 7) have a follow-up time of 2 weeks (efficacy study). The heart was excised, and the LAD, LCX and RCA dilated coronary arterial segments (orientation after the anatomical landmarks, as side branches, etc) were prepared from the epicardial surface. The dilated arteries of PS-balloon 1-4 were cut with the proximal and distal reference segments (at least 10 mm from the balloon-tip) and were fresh-frozen in liquid nitrogen for determination of the tissue paclitaxel concentrations.
(52) The PS-balloon 5-7 pigs underwent control angiography 2 weeks after balloon dilatation of the left coronary arteries, and then euthanasia was performed. The coronary arteries were prepared and stored in formalin for histomorphometric anaysis and immunohistochemistry.
(53) The experiments were conducted in the Institute of Diagnostics and Oncoradiology, University of Kaposvar, Hungary. “Principle of laboratory animal care” (NIH publication No. 86-23, revised 1985) and the relevant specific Hungarian laws were followed.
(54) 3. Measurement of Tissue Paclitaxel Levels:
(55) The paclitaxel concentration of plasma, LAD, LCX, and RCA were measured by HPLC (Anakat Institut für Biotechnologie GmbH, Berlin, Germany). Briefly, after thawing the tissues at ambient temperature they were weighted and depending on the weights different volumes of ethanol were added to the samples (sufficient ethanol to cover the tissue completely). The samples were treated with ultrasound for 40 minutes 200 μl of the samples were centrifuged.
(56) A calibration line was provided in the range between 50 ng/ml up to 5000 ng/ml. The samples for the calibration line were prepared by dilution of a stock solution with a concentration of 1000 μg/ml. An aliquot of all samples (samples from tissue and calibration line) were transferred into auto-sampler vials and the same volume of 0.1% formic acid was added. The flow rate of the HPLC system was 0.2 ml/min and the column was 0.2 ml/min and the column was ODS Hypersil from ThermoElectron Corporation, particle size 5μ, pore size 120 Å. The isocratic mobile phase consisted of 70% methanol and 30% 0.1% formic acid. Paclitaxel was detected by mass spectrometry operating in MRM-Mode (MRM=multiple reaction monitoring) with a transition of paclitaxel from 854 to 105 AMU.
(57) 4. Physical Signs/Symptoms:
(58) The ECG and blood pressure were recorded during the balloon dilatations, and at the follow-up coronary angiography.
(59) 5. Quantitative Coronary Angiography in the Efficacy Study:
(60) Pre- and post balloon dilatation, and at the 2 weeks follow up, quantitative angiographic parameters were measured by means of a computer-assisted quantitative coronary arteriographic edge detection algorithm (ACOMPC, Siemens, Germany). In order to minimize variation in the dimensions dependent on the cardiac cycle, end-diastolic frames were chosen for the assessment of pre-, post-dilatation and follow-up minimal lumen (MLD) and reference diameters (RD) and percent diameter stenoses (% DS) of the dilated segments.
(61) 6. Histopathology and Histomorphometry of the Dilated Arteries:
(62) Experienced observers have analysed all slides of the coronary arteries, without knowledge of groups. The arterial dilated segments with the distal and proximal reference segments were explanted. Three sections of each arterial segment were stained with hematoxylin-eosin and Verhoeff-van Gieson-elastin to determine the location and extent of injury.
(63) The quantitative analysis included: Lumen area (area of the vessel lumen, mm.sup.2), Neointima area (area of the neointimal tissue, mm.sup.2), IEL (internal elastic lamina) area (area within the IEL, mm.sup.2), Media area (area of the artery media, mm.sup.2), EEL (external elastic lamina) area (area within the EEL, mm.sup.2), Adventitial area (area of the vessel adventitia, mm.sup.2) Maximal neointimal thickness (at each stent strut site, mm) Percent area stenosis (neointimal area/IEL area, expressed as percentage, % AS
(64) For each arterial segment, the following histopathological parameters were described: inflammation score (adventitia, media, neointima, overall, score for each: 0-3), fibrinoid/fibrin deposits (score 0-3), haemorrhagia (score 0-3), necrosis (score 0-3),
(65) Results:
(66) No alterations in ECG, blood pressures and clinical symptoms were observed during the follow-up. No concomitant disease or fever were recorded.
(67) 7. Balloon Implantations:
(68) PS-Balloon-1:
(69) 1. Balloon: LAD Mid
(70) PS-balloon 3.0 mm diameter, 20 mm length,
(71) balloon inflation pressure 810.59 kPa (8 atm), balloon inflation time: 30 sec and 31 sec, deflation time: 15 sec and 13 sec.
(72) Spasm post balloon dilatation, 1 ml intracoronary nitroglycerine
(73) Final angio: OK
(74) 2. Balloon: LCX Mb (Bifurcation)
(75) PS-balloon 3.0 mm diameter, 20 mm length,
(76) balloon inflation pressure 810.59 kPa (8 atm), balloon inflation time: 30 sec and 27 sec, deflation time: 15 sec and 10 sec.
(77) No complication during balloon dilatation.
(78) Final angio: OK
(79) 3. Balloon: LCX Sb
(80) PS-balloon 2.5 mm diameter, 20 mm length,
(81) balloon inflation pressure 607.94 kPa (6 atm), balloon inflation time: 30 sec+30 sec, deflation time: 10 sec+10 sec.
(82) Final kissing balloon dilatation with the same balloons: 30 sec+30 sec
(83) Spasm post balloon dilatation, 1 ml intracoronary nitroglycerine
(84) Final angio: OK
(85) 4. Balloon: RCA Prox.
(86) PS-balloon 3.0 mm diameter, 20 mm length,
(87) balloon inflation pressure 1013.24 kPa (10 atm), balloon inflation time: 30 sec and 30 sec, deflation time: 5 sec and 5 sec.
(88) No complication during balloon dilatation.
(89) Final angio: OK
(90) PS-Balloon-2:
(91) 1. Balloon: LAD Mid (Bifurcation)
(92) PS-balloon 3.0 mm diameter, 20 mm length,
(93) balloon inflation pressure 810.59 kPa (8 atm), balloon inflation time: 32 sec+30 sec, deflation time: 10 sec+10 sec.
(94) No complication during balloon dilatation
(95) Final angio: OK
(96) 2. Balloon: LAD Diagonal Branch
(97) PS-balloon 2.5 mm diameter, 20 mm length,
(98) balloon inflation pressure 810.59 kPa (8 atm), balloon inflation time: 22 sec+22 sec, deflation time: 5 sec+5 sec.
(99) Final kissing balloon dilatation with the same balloons: 30 sec+30 sec
(100) Spasm post balloon dilatation, 1 ml intracoronary nitroglycerine
(101) Final angio: OK
(102) 3. Balloon: LCX MB (Bifurcation)
(103) PS-balloon 3.0 mm diameter, 20 mm length,
(104) balloon inflation pressure 810.59 kPa (8 atm) and 607.94 kPa (6 atm), balloon inflation time: 25 sec+30 sec, deflation time: 10 sec+10 sec.
(105) No complication during balloon dilatation.
(106) Final angio: OK
(107) 4. Balloon: LCX Marginal
(108) PS-balloon 2.5 mm diameter, 20 mm length,
(109) balloon inflation pressure 810.59 kPa (8 atm), balloon inflation time: 30 sec (2×), deflation time: 7 sec, 10 sec
(110) Final kissing balloon dilatation with the same balloons: 30 sec+30 sec
(111) Spasm post balloon dilatation, 1 ml intracoronary nitroglycerine
(112) Final angio: OK
(113) 5. Balloon: RCA Proximal
(114) PS-balloon 3.0 mm diameter, 20 mm length,
(115) balloon inflation pressure 1013.24 kPa (10 atm), balloon inflation time: 30 sec+30 sec, deflation time: 5 sec+7 sec.
(116) No complication during balloon dilatation.
(117) Final angio: OK
(118) 6. Balloon: RCA Distal
(119) PS-balloon 3.0 mm diameter, 20 mm length,
(120) balloon inflation pressure 1013.24 kPa (10 atm), balloon inflation time: 39 sec+30 sec, deflation time: 5 sec+5 sec.
(121) No complication during balloon dilatation.
(122) Final angio: OK
(123) PS-Balloon-3:
(124) 1. Balloon: LAD Mid
(125) PS-balloon 3.0 mm diameter, 20 mm length,
(126) balloon inflation pressure 810.59 kPa (8 atm), 911.92 kPa (9 atm) balloon inflation time: 30 sec+30 sec, deflation time: 10 sec+10 sec.
(127) No complication during balloon dilatation
(128) Final angio: OK
(129) 2. Balloon: LAD Proximal
(130) PS-balloon 3.0 mm diameter, 20 mm length,
(131) balloon inflation pressure 810.59 kPa (8 atm), 1013.24 kPa (10 atm) balloon inflation time 30 sec+30 sec: deflation time: 2 sec (2×).
(132) No complication during balloon dilatation.
(133) Final angio: OK
(134) 3. Balloon: LCX MB (Bifurcation)
(135) PS-balloon 3.0 mm diameter, 20 mm length,
(136) balloon inflation pressure 607.94 kPa (6 atm), balloon inflation time: 30 sec+30 sec, deflation time: 5 sec (2×).
(137) No complication during balloon dilatation.
(138) Final angio: OK
(139) 4 Balloon: LCX SB
(140) PS-balloon 2.5 mm diameter, 20 mm length,
(141) balloon inflation pressure 607.94 kPa (6 atm), balloon inflation time: 30 sec+30 sec, deflation time: 7 sec and 10 sec
(142) Final kissing balloon dilatation with the same balloons: 30 sec+30 sec
(143) Spasm post balloon dilatation, 1 ml intracoronary nitroglycerine
(144) Final angio: OK
(145) PS-balloon-4:
(146) 1. Balloon: LCX MB (Bifurcation)
(147) PS-balloon 3.0 mm diameter, 20 mm length,
(148) balloon inflation pressure 810.59 kPa (8 atm), balloon inflation time: 30 sec (2×), deflation time: 10 sec
(149) No complication during balloon dilatation
(150) Final angio: OK
(151) 2. Balloon: LCx SB
(152) PS-balloon 2.5 mm diameter, 20 mm length,
(153) balloon inflation pressure 607.94 kPa (6 atm), balloon inflation time: 30 sec+30 sec, deflation time: 5 sec (2×).
(154) Final kissing balloon dilatation with the same balloons: 30 sec+30 sec
(155) Spasm post balloon dilatation, 1 ml intracoronary nitroglycerine
(156) Final angio: OK
(157) 3. Balloon: LAD MB (Bifurcation)
(158) PS-balloon 3.0 mm diameter, 20 mm length,
(159) balloon inflation pressure 607.94 kPa (6 atm), balloon inflation time: 30 sec+33 sec deflation time: 5 sec and 5 sec.
(160) Final kissing balloon dilatation with the same balloons: 30 sec+30 sec
(161) No complication during balloon dilatation.
(162) Final angio: OK
(163) 4. Balloon: LAD SB Diagonal
(164) PS-balloon 2.5 mm diameter, 20 mm length,
(165) balloon inflation pressure 1013.24 kPa (10 atm), 607.94 kPa (6 atm) balloon inflation time: 30 sec+30 sec, deflation time: 5 sec and 5 sec
(166) Final kissing balloon dilatation with the same balloons: 30 sec+30 sec
(167) Spasm post balloon dilatation, 1 ml intracoronary nitroglycerine
(168) Final angio: OK
(169) 5. Balloon: RCA Distal
(170) PS-balloon 3.0 mm diameter, 20 mm length,
(171) balloon inflation pressure 911.92 kPa (9 atm), balloon inflation time: 30 sec+30 sec, deflation time: 5 sec+7 sec.
(172) No complication during balloon dilatation.
(173) Final angio: OK
(174) 6. Balloon: RCA Proximal
(175) PS-balloon 3.0 mm diameter, 20 mm length,
(176) balloon inflation pressure 810.59 kPa (8 atm), balloon inflation time: 29 sec+30 sec, deflation time: 5 sec+5 sec.
(177) No complication during balloon dilatation.
(178) Final angio: OK
(179) PS-balloon-5:
(180) 1. Balloon: LCX Proximal
(181) PS-balloon 3.0 mm diameter, 20 mm length,
(182) balloon inflation pressure 911.92 kPa (9 atm) balloon inflation time: 30 sec+30 sec, deflation time: 5 sec
(183) No complication during balloon dilatation
(184) Final angio: OK
(185) 2. Balloon: LCX Distal
(186) Allegro 2.5 mm diameter, 20 mm length,
(187) balloon inflation pressure 810.59 kPa (8 atm) and 607.94 kPa (6 atm), balloon inflation time: 30 sec+30 sec, deflation time: 11 sec.
(188) Spasm post balloon dilatation, 2×1 ml intracoronary nitroglycerine
(189) Final angio: OK
(190) 3. Balloon: LAD Proximal
(191) PS-balloon 3.0 mm diameter, 20 mm length,
(192) balloon inflation pressure 810.59 kPa (8 atm), balloon inflation time: 30 sec+30 sec deflation time: 5 sec.
(193) No complication during balloon dilatation.
(194) Final angio: OK
(195) 4. Balloon: LAD Distal
(196) Allegro 2.5 mm diameter, 20 mm length,
(197) balloon inflation pressure 607.94 kPa (6 atm) balloon inflation time: 30 sec+30 sec, deflation time: 13 sec
(198) No complication during balloon dilatation.
(199) Final angio: OK
(200) PS-balloon-6:
(201) 1. Balloon: LCX Proximal
(202) PS-balloon 3.0 mm diameter, 20 mm length,
(203) balloon inflation pressure 810.59 kPa (8 atm) balloon inflation time: 30 sec+30 sec, deflation time: 5 sec
(204) No complication during balloon dilatation
(205) Final angio: OK
(206) 2. Balloon: LCX Distal
(207) Allegro 2.5 mm diameter, 20 mm length,
(208) balloon inflation pressure 607.94 kPa (6 atm), balloon inflation time: 30 sec+30 sec, deflation time: 10 sec.
(209) No complication during balloon dilatation.
(210) Final angio: OK
(211) 3. Balloon: LAD Proximal
(212) PS-balloon 3.0 mm diameter, 20 mm length,
(213) balloon inflation pressure 810.59 kPa (8 atm), balloon inflation time: 30 sec+30 sec deflation time: 5 sec.
(214) No complication during balloon dilatation.
(215) Final angio: OK
(216) 4. Balloon: LAD Distal
(217) Allegro 2.5 mm diameter, 20 mm length,
(218) balloon inflation pressure 607.94 kPa (6 atm) balloon inflation time: 30 sec+30 sec, deflation time: 10 sec
(219) Spasm post balloon dilatation, 2×1 ml intracoronary nitroglycerine, 5000 IU Heparin ic
(220) Final angio: OK
(221) PS-balloon-7:
(222) 1. Balloon: LCX Proximal
(223) PS-balloon 3.0 mm diameter, 20 mm length,
(224) balloon inflation pressure 810.59 kPa (8 atm) balloon inflation time: 30 sec+30 sec, deflation time: 5 sec
(225) No complication during balloon dilatation
(226) Final angio: OK
(227) 2. Balloon: LCX Distal
(228) Allegro 2.5 mm diameter, 20 mm length,
(229) balloon inflation pressure 810.59 kPa (8 atm) and 607.94 kPa (6 atm), balloon inflation time: 30 sec+30 sec, deflation time: 12 sec.
(230) No complication during balloon dilatation.
(231) Final angio: OK
(232) 3. Balloon: LAD Proximal
(233) PS-balloon 3.0 mm diameter, 20 mm length,
(234) balloon inflation pressure 810.59 kPa (8 atm), balloon inflation time: 30 sec+30 sec deflation time: 5 sec.
(235) No complication during balloon dilatation.
(236) Final angio: OK
(237) 4. Balloon: LAD Distal
(238) Expleo 3.0 mm diameter, 20 mm length,
(239) balloon inflation pressure 405.29 kPa (4 atm) balloon inflation time: 30 sec+30 sec, deflation time: 12 sec
(240) No complication during balloon dilatation.
(241) Final angio: OK
(242) 8. Tissue Paclitaxel Concentration:
(243) The tissue paclitaxel concentration was very high, in some bifurcation over 1000 uM/L. The calibration curve and the tissue probes have been controlled, but no mistake in measurements were found. Some other parallel measured tissues contained very small amount of paclitaxel, which confirmed the accuracy of the measurements. Furthermore, 5 samples have been sent 1 week later, they have shown similar high concentration of paclitaxel with the new calibration curve. Table 2 presents the mean and standard deviations of the values in single vessel and bifurcation dilatation.
(244) There were large scattering of the data, but the data are consequent; as the values are lower at 12 h as compared with the values at 45 min, and the bifurcation values are 2-3× higher than the single vessel values (Table 2).
(245) TABLE-US-00002 TABLE 2 Coronary artery tissue paclitaxel concentration after balloon dilatation with the inventive paclitaxel-shellac coated catheter balloon. Tissue paclitaxel Time after balloon Time after balloon concentration (μM/L) dilat. Mean 45 min dilat. Mean 12 h Single vessel (n = 4) (n = 4) Dilated segment (μM/L) 184.4 ± 178.4 39.3 ± 48.7 Proximal reference segment 111.0 ± 79.5 38.8 ± 74.3 Distal reference segment (μM/L) 62.1 ± 77.3 38.1 ± 33.1 Bifurcation (n = 3) (n = 3) Bifurcation main branch (μM/L) 498.1 ± 339.9 267.8 ± 297.3 Bifurcation main branch proximal 196.2 ± 320.4 161.2 ± 139.8 reference segment (μM/L) Bifurcation main branch distal 224.5 ± 170.4 100.0 ± 134.1 reference segment (μM/L) Bifurcation side branch (μM/L) 220.7 ± 306.4 26.1 ± 42.1 Bifurcation side branch distal 42.1 ± 61.7 37.0 ± 63.5 reference segment (μM/L)
Example 6: Biological Tests II
(246) Animal Preparation
(247) After overnight fasting, 33 domestic pigs (weight 18-30 kg) were premedicated with intramuscular injection of 12 mg/kg ketamine hydrochloride, 1 mg/kg xylazine and 0.04 mg/kg atropine. The anesthesia was deepened with isofluran and O.sub.2 via a mask, followed by intratracheal intubation. The anesthesia was maintained with 1.5-2.5 vol % isofluran, 1.6-1.8 vol % O.sub.2 and 0.5 vol % N.sub.2O. O.sub.2 saturation. Blood pressure and electrocardiogram were monitored continuously. Arteriotomies of the right femoral arteries were performed under sterile conditions, and a 6F introduction sheath was inserted. After administration of 200 IU/kg of heparin sodium, selective angiography of the left and right coronary arteries were performed and a guide-wire was introduced into the distal part of the left anterior descending (LAD) and left circumflex (LCx) coronary arteries. The balloon catheters (2.75-3.0 mm in diameter, 15 mm in length) were inserted into the LAD past the origin of the first major diagonal branch, and into LCx beyond the origin of the first marginal branch, and balloon dilation was performed. Coronary angiography confirmed the full contact of the balloon with the vessel wall during each balloon inflation. The inflation time was chosen in accordance with the protocol, e.g. either the safety or the efficacy phase of the study. The animals were then euthanized for the safety study or allowed to recover for the efficacy study. The experiments were conducted in the Institute of Diagnostics and Oncoradiology, University of Kaposvar, Hungary. The animal investigations conform to the “Position of the American Heart Association on Research Animal Use”, adopted by the AHA on Nov. 11, 1984, and the relevant specific Hungarian laws were followed.
(248) Local Drug Delivery Device
(249) The DIOR Paclitaxel-shellac catheter balloon (Eurocor GmbH) is a coronary dilation balloon for human use with a 3.0 μg/mm.sup.2 balloon-surface paclitaxel-shellac coating. The drug is dissolved in shellac, which is composed of a network of hydroxy fatty acid esters and sesquiterpene acid esters with a molecular weight of about 1000; aleuritic acid and jalaric acid and/shelloic acid are the major constituents of shellac.
(250) The 1:1 mixture of paclitaxel and shellac is coated onto the microporous DIORballoon-surface structure. During the insertion of the DIOR Paclitaxel-shellac catheter balloon (Eurocor GmbH) and tracking to the coronary lesion, the three-folded DIOR Paclitaxel-shellac catheter balloon protects the loaded drug from an early wash-off effect.
(251) Safety Study
(252) For measurements of tissue paclitaxel concentration after balloon inflation, the DIOR Paclitaxel-shellac catheter balloon (Eurocor GmbH) was inserted into the LAD and LCx. To assess the increase in tissue Paclitaxel concentrations as a function of balloon inflation times, the DIOR Paclitaxel-shellac catheter balloons were inflated for 15 s in 10 coronary segments, for 20 s in 6 coronary segments, for 30 s in 6 coronary segments, for 45 s in 7 coronary segments and 2×30 sec in 6 coronary segments and at 607.94-1418.53 kPa (6-14 atm) (1.3:1 balloon/artery ratio). Blood samples were taken 5, 10 and 30 min after balloon inflation. Euthanasia was performed with saturated potassium chloride at 45 min or 12 h after DIOR Paclitaxel-shellac catheter balloon (Eurocor GmbH) inflation. The balloons were then stored for measurements of remnant surface paclitaxel amount. The LAD and LCx dilated coronary arterial segments were prepared with additional proximal and distal reference segments (max. 10 mm proximal or distal from the dilated segment), and fresh-frozen for determination of tissue paclitaxel concentrations. Tissue samples (connective tissue, fat and myocardium), 1, 2 and 3 mm beneath the artery were prepared for determination of the depth of vertical paclitaxel penetration into the tissue.
(253) Measurement of Tissue, Balloon Surface and Plasma Paclitaxel Concentrations
(254) The paclitaxel concentration in the artery walls, the underlying tissue at 1, 2 and 3 mm deep layers, balloon surface and plasma was measured by high-performance liquid chromatography (HPLC). After thawing, the tissues were weighed at ambient temperature and, depending on weight different volumes of ethanol were added to the samples (sufficient ethanol to cover the tissue completely). The samples were then treated with ultrasound for 40 min, and 200-μL aliquots were then centrifuged and stored for subsequent measurements. A calibration line was produced in the range between 50 and 5000 ng/mL. The samples for the calibration line were prepared by dilution of a stock solution with a concentration of 1000 μg/mL. Aliquots of all samples (samples from tissue and calibration line) were transferred into auto-sampler vials and the same volume of 0.1% formic acid was added. The flow rate of the HPLC system was 0.2 mL/min through a column of ODS Hypersil (ThermoElectron Corporation), particle size 5μ, pore size 120 Å. The isocratic mobile phase consisted of 70% methanol and 30% 0.1% formic acid. Paclitaxel was detected by mass spectrometry in multiple reaction monitoring mode with a transition of paclitaxel from 854 to 105 AMU. The tissue paclitaxel concentration was expressed in μM/L, which measure is independent from the sample weight. The plasma paclitaxel amount was given in ng/mL.
(255) Efficacy Study
(256) The neointimal proliferation caused by balloon overstretch injury (1.3:1 balloon/artery ratio) was compared using uncoated AMADEUS Supercross catheter balloon (n=6) or DIOR Paclitaxel-shellac catheter balloon (n=6) in the LAD and LCx. Loading dose of clopidogrel (300 mg per os) and acetylsalicylic acid (250 mg per os) were administered 24 h prior to the procedure. The medication was continued with a daily dose of 75 mg clopidogrel and 100 mg acetylsalicylic acid during the 2-week follow-up (FUP). Each pig was treated with both uncoated AMADEUS Supercross catheter balloon and DIOR Paclitaxel-shellac catheter balloon in a randomized fashion (DIOR Paclitaxel-shellac catheter balloon in either LAD or LCx). The balloons (2.75-3 mm of diameter, 15 mm of length) were inflated with 1013.24-1823.84 kPa (10-18 atm) for 30 s in order to achieve the 1.3:1 balloon:artery ratio. Control angiography was performed at 2-week FUP, followed by euthanasia. For histopathological and histomorphometric analyses, the coronary arteries were flushed with 100 ml saline followed by pressure fixation in 4% buffered formaldehyde for 30 min at 100-110 mmHg. The arteries were then cut from the epicardial surface and the location of the previous dilation was carefully identified based on the anatomical landmarks (side branches). The dilated segment (divided into three sections, such as proximal, mid and distal dilated segments), the proximal and distal reference segments (max. 10 mm proximal or distal from the dilated segment) were then fixed in 2% buffered formalin. Following this preparation, the arterial sections were embedded in paraffin and cut into 4-6-μm-thick slices and routinely stained with hematoxylin-eosin and Verhoeff-van Gieson-elastin.
(257) Histopathology and Histomorphometry of the Arteries 2 Weeks after Overstretch Injury
(258) The histological analysis was performed by experienced investigators blinded to the treatments and focused on the arterial injury, and measurements of the neointimal hyperplasia. The following histopathological parameters were measured: injury score, fibrin and inflammation scores, and endothelialization. Vessel injury was determined by the anatomic vessel structures similar to the injury score after stenting (Schwartz et al., J Am Coil Cardiol, 1992, 19, 267-74), and adapted for balloon injury only (Rosenthal et al., Circulation, 2001, 104, 2222-2227). A numeric value was assigned according to the of severity injury: Grade 0: (no injury): internal (IEL) and external elastic lamina (IEL) and media intact; Grade 0.05: IEL minimal disruption, media and EEL intact; Grade 1: IEL lacerated, media and EEL intact; Grade 1.5 IEL lacerated, media<half thickness lacerated, EEL intact; Grade 2: IEL lacerated, media>half thickness lacerated, EEL intact; Grade 2.5: IEL and media (full thickness) lacerated, IEL minimal disruption; Grade 3: IEL, media (full thickness) and EEL lacerated. Inflammation score was graded as 0 for no inflammation to minimal amount of interspersed inflammatory cells in media or adventitia; 1 for mild inflammatory infiltration or focally moderated in <25% of the vessel area in media or adventita; 2 for moderate inflammatory infiltration or focally marked in 25-50% of the vessel area in media or adventitia; 3 for heavy inflammatory infiltration or focally marked in >50% of the vessel area in media or adventitia, and 4 for granulomatous inflammatory reaction in any layer of the artery. Fibrin score was graded from 0 to 3 as no fibrin deposition or mild, moderate or heavy fibrin deposition, involving <10%, 10-25% or >25% of the circumference of the vessel, respectively. Endothelialization was evaluated with a score system comprising absent, partial or complete. The following quantitative histomorphometric parameters of the dilated segment, and proximal and distal reference segments were measured: 1) lumen area, 2) IEL area, 3) EEL area, and 4) maximal neointimal thickness. The calculated histomorphometric parameters were as follows: 1) neointima area (difference between IEL and lumen area), 2) media area (difference between EEL and IEL area), 3) % area stenosis ((neointimal area/IEL area)*100), 3) remodeling index (EEL area of the dilated arterial segment/EEL area of the proximal reference segment
(259) Tissue Distribution of Paclitaxel Using Paclitaxel-Eluting Stent and DIOR Paclitaxel-Shellac Catheter Balloon
(260) Tissue distribution of paclitaxel after coronary intervention with fluorescent-paclitaxel (Oregon Green 488 Fluorecent paclitaxel conjugate, Molecular Probes, Invitrogen, Paisley PA4 9RF, UK) conjugate-coated stent and DIOR catheter balloon (both 3.0 mm in size and 15 mm in length, balloon inflation time 30 s with 1013.24 kPa (10 atm)) was compared. The arteries were prepared from the epicardial surface. The stent was removed carefully, and the arteries were cut longitudinally and unfolded. The intimal surface was displayed with fluorescent microscopy.
(261) Results
(262) There was no procedural or post-procedural complication after the use of the DIOR Paclitaxel-shellac catheter balloon for dilation of the coronary arteries. Safety study Paclitaxel concentrations in arterial tissue 45 min and 12 h post-dilation increased with increasing duration of balloon inflation times (15, 20, 30 and 45 s) reaching a plateau with 30 s (
(263) Efficacy Study
(264) Two weeks post-overstretch injury, histopathological analyses revealed similar fibrin score and injury score in the groups. The inflammation score was somewhat higher in the uncoated AMADEUS Supercross catheter balloon group, without significant difference between the groups (
(265) Tissue Distribution of Paclitaxel
(266) Fluorescence paclitaxel derivative-coating of DIOR balloon showed a homogenous distribution of the drug onto the vessel, in contrast with the uneven distribution caused by the fluorescence paclitaxel derivative-coated stent.
REFERENCE LIST
(267) 1. Lumen 2. Neointima 3. Internal elastic lamina 4. Media 5. External elastic lamina
DESCRIPTION OF FIGURES
(268)
(269) Inflation time-dependent tissue and balloon surface paclitaxel concentrations DIOR Paclitaxel-shellac coated catheter balloons were dilated in coronary artery tissue for 15 s, 20 s, 30 s, 45 s and 60 s. The Paclitaxel concentration in the proximal-, dilated-, and distal segment was measured after 45 min post-dilation (A) or after 12 h post-dilation (B) and is displayed in μM/L. The remaining Paclitaxel on the surface of the catheter balloons after 15 s, 20 s, 30 s, 45 s and 60 s inflation was measured and is displayed in μg (C). A. Coronary artery tissue paclitaxel concentrations of dilated segments (middle bar), proximal segments (left bar) as well as distal reference segments (right bar) measured 45 min after 15, 20, 30, 45 and 60 s balloon inflations. B. Coronary artery tissue paclitaxel concentrations of dilated segments (middle bar), proximal segments (left bar) as well as distal reference segments (right bar) measured 12 h after 15, 20, 30, 45 and 60 s balloon inflations. C. Remnant paclitaxel amount of the balloon surface, after 15, 20, 30, 45 and 60 s balloon inflations.
(270)
(271) Inflation time-dependent tissue and plasma paclitaxel concentrations DIOR Paclitaxel-shellac coated catheter balloons were dilated in coronary artery tissue for 15 s, 20 s, 30 s, 45 s and 60 s and the vertical penetration (A) as well as the plasma Paclitaxel concentration was measured (B). A. Vertical penetration of the paclitaxel at 1 mm (left bar) and 2 mm (right bar) deepness depending on balloon inflation time measured at 45 min post-dilation. B. Plasma paclitaxel concentration 5 min post-balloon inflation. Paclitaxel could be measured only 60 s balloon inflation time. No paclitaxel was detected 10 min postdilation (not shown).
(272)
(273) Histomorphometric parameter of dilated arteries 2 weeks post-balloon dilatation with uncoated AMADEUS Supercross catheter balloon or DIOR Paclitaxel-shellac catheter balloon. A dilatation time of 30 seconds was used.
(274)
(275) Histology of overstretch injury after DIOR Paclitaxel-shellac catheter balloon or uncoated AMADEUS Supercross catheter balloon use Representative histologic slides 2 weeks after balloon overstretch injury with conventional (A) or DIOR Paclitaxel-shellac catheter balloon (B) balloon.
(276)
(277) Differences between the DIOR Paclitaxel-DMSO catheter balloon and DIOR Paclitaxel-shellac catheter balloon