Patent Application
20150216798
The present invention is related to formulations containing a combination of dapoxetine or a pharmaceutically acceptable salt thereof with a phosphodiesterase Type 5 inhibitor or a pharmaceutically acceptable salt thereof. The invention is also related to a process for preparation a similar formulation and its use in treatment of erectile dysfunction.
Selective serotonin reuptake inhibitors (SSRI) are used in many types of depression including the endogenous type, long-term prophylaxis in recurrent depressions, obsessive-compulsive disorders, panic attacks, social fobias, and blumia nervosa. Dapoxetine, first described at European patent application no EP 0288188 B1, is a selective serotonin reuptake inhibitor. Dapoxetine is used for treatment of depression and premature ejaculation and its chemical formula is shown in formula I. In addition, it was approved in Sweden and Finland for the treatment of premature ejaculation.
Dapoxetine is rapidly absorbed following oral administration and undergoes a rapid disintegration by near-complete binding to plasma proteins. Therefore, it reaches its peak plasma concentration (Cmax) 1 hour following oral administration. Orally given tablets are available in the market with the commercial name Priligy® containing 30 mg or 60 mg dapoxetine hydrochloride as active substance and lactose monohydrate, microcrystalline cellulose, croscarmellose sodium, colloidal anhydrase cilica, magnesium stearate, hypromellose, titanium dioxide (E171), triacetine, black iron oxide (E172), and yellow iron oxide as inactive ingredients.
The most common problem with oral formulations of dapoxetine is its bitter taste. To mask its bitter taste, the tablets are generally coated with coating agents. In addition, sweetener mixtures or cahion exchange resins have been used.
Phosphodiesterase type 5 inhibitors (PDE5 inhibitor) are used in treatment of erectile dysfunction (ED). PDE5 inhibitors selectively and effectively block phosphodiesterase enzyme and increase cyclic guanosine monophosphate (cGMP) levels in cavernous smooth muscle cells. The most commonly used phosphodiesterase inhibitors are avanafil, lodenafil, mirodenafil, sildenafil, tadalafil, vardenafil, and udenafil.
Avanafil is a PDE5 inhibitor used in the ED treatment and sold under the brand name of Stendra®. It exerts a more rapid effect compared to other PDE5 inhibitors. Its chemical name is (S)-4-[(3-Chloro-4-methoxybenzyl)amino]-2-[2-(hydroxymethyl)-1-pyrrolidinyl]-N-(2pyrimidinylmethyl)-5-pyrimidinecarboxiamide. Its chemical Formula is shown in Formula II.
Lodenafil is a PDE5 inhibitor used in the ED treatment sold under the brand name of Helleva®. It has been formulated as a dimer and it is transformed into two active lodenafil molecules after it is taken into the body. This increases its bioavailability. Its chemical name is bis-(2-{4-[4-ethoxy-3-(1-methyl-7-oxo-3-propyl-6,7-dihydro-1H-pyrazole[4,3-d]pyrimidine-5-il)-benzenesulfonyl]piperazine-1-il}-ethyl)carbonate. Its chemical structure is given in Formula III.
Mirodenafil is a PDE5 inhibitor used in the ED treatment and sold under the brand name of Mvix®. It is also found in the market under the brand name of Mvix S®. Its chemical name is 5-Ethyl-3,5-dihydro-2-[5-([4-(2-hidroxyethyl)-1-piperazinyl]sulfonyl)-2-propoxyiphenyl]-7-propyl-4H-pyrrole[3,2-d]pyrimidine-4-on. Its chemical structure is given in Formula IV.
Sildenafil is a PDE5 inhibitor used in the treatment of ED and pulmonary arterial hypertension and is sold under the brand name of Viagra® and Revatio®. Its chemical name is 1-[4-ethoxy-3-(6,7-dihydro-1-methy-7-oxo-3-propyl-1H-pyrrazole[4,3-d]pyrimidine-5-yl)phenylsulfonyl]-4-methylpiperazine. Its chemical structure is shown in Formula V.
Tadalafil is a PDE5 inhibitor used in treatment of ED and PAH. It has a longer half life compared to other PDE5 inhibitors (mean 17,5 hours). Its chemical name is (6R-trans)-6-(1,3-benzodioxol-5-yl)-2,3,6,7,12,12a-hexahydro-2-methyl-pyrazine [1′,2′:1,6]pyrido[3,4-b]indol-1,4-dion. Its chemical structure is shown in Formula VI.
Vardenafil is a PDE5 inhibitor used in the ED treatment sold under the brand name of Levitra®. It is also sold in the form of coated tablet form under the brand name of Staxyn®. Its chemical name is 4-[2-Ethoxy-5-(4-ethylpiperazine-1-yl)sulfonyl-fenyl]-9-methyl-7-propyl-3,5,6,8-tetrazbicyclo[4.3.0]nona-3,7,9-triene-2-on. Its chemical structure is shown in Formula VII.
Udenafil is a PDE5 inhibitor used in the ED treatment sold under the brand name of Zydena®. Its chemical name is 3-(1-methyl-7-oxo-3-propyl-4,7-dihydro-1H-pyrrazole[4,3-d]pyrimidine-5-yl)-N-[2-(1-methylpyrrolidine-2-ypethyl]-4-propoxybenzenesulfonamide. Its chemical structure is shown in Formula VIII.
It is known that PDE5 inhibitors poorly disintegrate in water. Therefore, they have a low and inconsistent bioavailability. To solve this problem, several methods have been employed. For example, tadalafil (although disintegrates poorly in water) can disintegrate in organic solvents such as dimethylformamide and dimethylsulfoxide. In the patent No EP1200091 B1, hydrophilic solvents such as polyethylene glycol 400, propylene glycol, and glycofurole were used for the tadalafil which poorly disintegrated in water. In this patent, tadalafil disintegrated in hydrophilic solvents was packed in soft capsules.
Various formulations and methods are already known to prepare formulations disintegrated orally. However, treatment compliance with orally disintegrated formulations compared with conventional solid dosage forms such as capsules and tablets have gained importance. This subject is especially important for those who have difficulty in swallowing. In addition, one needs to ingest liquids with many drugs with resulting gastric volume increase which increases the likelihood of nausea and vomiting. The main advantage of orally disintegrating dosage forms is probably the rapid disintegration of solid dosage forms in oral cavity to form a solution or suspension without the need of fluid ingestion. By this way, it is sufficient to administer the dosage form immediately before a patient needs it. Furthermore, absorption of hydrophobic PDE5 inhibitors is low in stomach due to their poor disintegration in gastric fluid. Therefore, an orally disintegrating dosage form is advantageous in administration of drugs containing PDE5 inhibitors and dapoxetine and it increases treatment compliance along with recommended pharmaceutical therapies.
Besides, the orally disintegrating dosage form is one of the advantageous methods to deliver these drugs to such patients. By administering the orally disintegrating dosage forms, faster absorption of the drug occurs through buccal mucosa and it may reduce the first pass effect leading to better efficacy of the drug. This dosage form enhances the clinical effects of some drugs by leading to increase inthe bioavailability and a reduction in the side effects because of avoidance offirst-pass liver metabolism.
It is clear to develop orally disintegrating compositions are difficult because of a number of different reasons. A satisfactory orally disintegrating dosage form needs to meet a number of requirements. Firstly, a disintegration in oral cavity earlier than intended may create some problems due to unpleasant taste of the active substance. Furthermore, these compositions should be highly porous and not very hard. These porous compositions tend to be very sensitive to moisture. As a result, they may have some stability problems. Lastly, an orally-disintegrated composition of suitable organoleptic and pharmacokinetic properties must also be manufactured commercially useful rates and yields.
To fulfill all these requirements, the formulation for a specific drug needs to be adapted in particular by a careful selection of excipients used. The selected excipients, however, may led to formulations which are not bioavailable to the corresponding conventional dosage forms. Therefore, they have to be chosen very carefully. In addition, precautions have to be taken at the preparation, packaging, handling, and storing of the finished dosage forms of orally disintegrating compositions since they tend to be both hygroscopic and friable.
Thus, there is a need of an orally disintegrating composition containing dapoxetine and a PDE5 inhibitor and a process to prepare such compositions. Further advantages and embodiments of the present invention will become apparent from the following description.
The main object of the present invention is, by employing appropriate excipients, to prepare an orally disintegrating composition of dapoxetine or a pharmaceutically acceptable salt thereof with a PDE5 inhibitor or a pharmaceutically acceptable salt thereof beneficial in treatment of erectile dysfunction and related symptoms which overcomes the above-mentioned problems.
Another object of the present invention is to develop a simple, cost-effective, and time-saving process to prepare an orally disintegrating formulation of dapoxetine or a pharmaceutically acceptable salt with a PDE5 inhibitor or a pharmaceutically acceptable salt thereof.
Yet another object of the present invention is to provide an orally disintegrating combination of dapoxetine or apharmaceutically accepted salt thereof with a PDE5 inhibitor or a pharmaceutically accepted salt thereof which has good mechanical strength enoughto be processed in high tabletting machines (for example, adequate rigidity and low friability) and shipped in low-cost packages.
According to another embodiment, the orally disintegrating composition comprises dapoxetine or a pharmaceutically accepted salt thereof in the ratio of 1.0 to 30.0% and a PDE5 inhibitor or a pharmaceutically accepted salt thereof in the ratio of 1.0 to 40.0% by total composition weight.
Another object of the invention is to prepare an orally disintegrating composition containing a combination of dapoxetine or a pharmaceutically acceptable salt thereof with a PDE5 inhibitor or a pharmaceutically acceptable salt thereof, which has adequate bioavailability and is stable during shelf life. In line with this purpose, in the present invention, unexpected benefits were obtained with this orally disintegrating composition which was comparable with available conventional solid dosage forms.
The appropriate PDE5 inhibitor used in orally disintegrating compositions is selected from among the group comprising avanafil, lodenafil, mirodenafil, sildenafil, tadalafil, vardenafil, and udenafil; the preferred PDE5 inhibitor is tadalafil.
Each PDE5 inhibitor has a different onset and duration of effect. After the oral administration, the onset of action of sildenafil is 1 hour whereas it is 15 minutes for tadalafil. The duration of effect of sildenafil is 4 hours whereas tadalafil may be effective as long as 36 hours. Tadalafil is preferred in situations where a rapid onset of action is desirable.
Orally disintegrating compositions appropriate for the present invention further comprise one or more dispersing agents.
According to one embodiment, the amount of dispersing agent is 1 to 90%by weight, preferably 5-50% by weight, and more preferably, 15-40% by weight of the total composition, and said amount makes it possible to significantly improve compressibility, reduce friability and achieve a substantial reduction in disintegration time. Higher quantities may have negative mechanichal strength of the formula and lower quantities may worsen the disintegration time.
Dispersing agent appropriate for the invention and used in the composition is selected from the group comprising calcium silicate, heavy magnesium carbonate, cross-linked povidone, carboxymethyl cellulose calcium, magnesium aluminium silica. sodium dodesyl sulfate, sodium carboxymethly cellulose, croscarmellose sodium, docusate sodium, low-substitute hydroxypropylcellulose; microcrystalline cellulose and guar glue mixture (Avicel CE-15); poloxamere or mixtures thereof. It is selected preferably from the group comprising calcium silicate, heavy magnesium carbonate, crosspovidon or mixtures thereof. Dispersing agent of the present invention is preferably calcium silicate; mean particle size of calcium silicate is less than 50 microns, preferably less than 20 microns, and more preferably less than 10 microns.
According to this regulation of the invention, orally disintegrating composition comprises calcium silicate, heavy magnesium carbonate, crosspovidon or mixtures thereof in the ratio of 1.0-90.0%, preferably 5.0-50.0%, and more preferably 15.0-40.0% by the total composition weight and the formulation disintegrates in oral cavity in less than 60 seconds, preferably less than 30 seconds, and more preferably less than 20 seconds.
The interval selected for the ratio of the dispersing agents in the composition to the dapoxetine has been unexpectedly found to produce an orally disintegrating composition overcoming the above-mentioned disadvantages of orally disintegrating compositions. The ratio of total weight of the dispersing agents to the total weight of dapoxetine is between 0.5:1 and 5:1.
It has been unexpectedly discovered that use of a binder in addition to the dispersing agent in the orally disintegrating composition of a combination of dapoxetine or a pharmaceutically acceptable salt thereof with a PDE5 inhibitor or a pharmaceutically acceptable salt thereof has a synergistic effect on dinsintegration time. The appropriate binder is selected from the group comprising cellulose derivatives such as pullulan, starch, polyvinylpyrrolidone (povidone), gelatin, sugars, glucose, natural glues, gums, synthetic celluloses, polymethacrylate, hydroxypropyl methyl cellulose, microcrystalline cellulose, hydroxypropyl cellulose, carboxy methyl cellulose, methyl cellulose. Polyvinylpyrrolidone (povidone), pullulan, microcrystalline cellulose or mixtures thereof are preferably used as binder. In compliance with this object of the invention, the orally disintegrating compositions comprise one or more binders in the ratio of 0.1 to 20.0%, and preferably in the ratio of 0.2-15.0% by the total composition weight.
Compositions suitable for the present invention may be in the form of tablet, orally disintegrating tablet, film-coated tablet, effervescent tablet, layered tablet, modified-release tablet, micro tablet, mini tablet, or pellet. Compositions appropriate for the invention are preferably in the form of orally disintegrating tablet.
Another object of the present invention is to develop orally disintegrating tablet formulations with optimal mechanical resistance. The present invention meets this demand and explains tablet formulations rapidly disintegrated in oral cavity. These tablet compositions have a pleasant mouth feel and good mechanical strength. These tablets are robust (e.g., low friability, adequate hardness) enough to be processed in high speed tableting machines and shipped in low cost packages, and at the same time retain rapid disintegration or dissolution properties. These orally disintegrating compositions are bioavailable in correspondence with the conventional solid dosage formulations and stable throughout the shelf-life.
According to another object of the present invention, the hardness of the orally disintegrating tablet is between 5 N and 100 N and preferably 20 N and 45 N, and its friability is below 1.0%.
It is known that, to develop orally disintegrating compositions are difficult because of several different reasons. An appropriate orally disintegrating dosage form should meet some requirements. First, it should rapidly disintegration oral cavity. On the other hand, release or disintegration of the active substance earlier than intended may pose some problems due to generally unpleasant taste of the active agent. In addition, compositions should be highly porous but not too hard. These porous compositions are highly sensitive to moisture. As a result, they may have some stability problems.
However, orally disintegrating tablets should be pleasant-tasting to be pharmaceutically acceptable, e.g. they should possess acceptable organoleptic properties such as giving a pleasant sensation or taste to mouth because orally disintegrating tablets are designed to disintegrate rapidly in oral cavity without remaining substantial amounts of the active substances. In addition, the orally disintegrating tablets should possess acceptable pharmacokinetic properties and bioavailability to provide desired therapeutic effect. In contrast, composition substances in the formulation supporting rapid release may cause unpleasant sensation or taste in mouth. Lastly, orally disintegrating compositions with suitable organoleptic and pharmacokinetic properties should be manufactured at commercially beneficial rates and yields.
Consequently, an acceptable orally-disintegrating composition should balance these contradictory characteristics to obtain a composition possessing acceptable pharmacokinetic properties, having a pleasant taste (for example, taste-masked), and rapid disintegration.
To fulfill all these requirements, a formulation for a specific drug particularly necessitates careful selection of the excipients. However, the selected excipients could yield formulations with no good bioavailability for the corresponding conventional dosage forms. Therefore, they should be selected very carefully.
The invention contains at least one pharmaceutically acceptable excipient selected from the group comprising of fillers, lubricants, sweeteners, aromatic agents, or coloring agents.
Suitable fillers may include, but not limited to, mannitol, spray-dried mannitol; polysaccharides such as microcrystalline cellulose, dibasic calcium phosphate dihydrate, lactose, sugars, sorbitol; mixture of microcrystalline cellulose and guar glue (Avicel CE-15); mixture of mannitol, polyplasdone, and ciolide (Phramaburst); mixture of mannitol, crospovidone, and polyvinyl acetate (Ludiflash); isomalt, sucrose, and inorganic salts such as calcium salts, and their mixtures; they preferably contain mannitol, microcrystalline cellulose or mixtures thereof. Orally disintegrating tablet formulations according to the invention comprise fillers in the ratio of 2.0 to 90.0% and preferably 10.0-75.0% by the total tablet weight.
Suitable lubricants may include, but not limited to, sodium stearyl fumarate, magnesium stearate, polyethylene glycol, stearic acid, metal stearates, boric acid, sodium chloride benzoate and acetate, sodium or magnesium lauryl sulfate, and mixtures thereof; the preferred lubricant is sodium stearyl fumarate. Sodium stearyl fumarate is highly effective lubricant, being less hydrophobic than magnesium stearate and has a less retarding effect on tablet disintegration compared to magnesium stearate. In addition, sodium stearyl fumarate does not have problems due to overblending observed in magnesium stearate. Consistent with this object of the invention, the orally disintegrating tablet formulations comprise sodium stearyl fumarate in the ratio of 0.1 to 10.0% and preferably 0.2 to 5.0% by the total tablet weight.
Suitable sweeteners may include, but not limited to, sucralose, acesulfame-K, aspartame, saccharine or sodium and calcium salts of saccharine, sodium cyclamate, sucrose, fructose, glucose, sorbitol, and mixtures thereof; the preferred sweetener is sucralose. In the present invention, sucralose is present in the ratio of 0.01 to 5.0% and preferably 0.05 to 2.0% by the total tablet weight.
Suitable aromatic agents may include, but not limited to, fruit aromas such as orange, banana, strawberry, cherry, wild cherry, and lemon, other aromas including cordamom, anasone, mint, menthol, vanillin, and ethyl vanillin, and mixtures thereof; the preferred aromatic agent is selected from fruit aromas, such as orange aroma. According to the invention, the aromatic agent is in the ratio of 0.05-5.0% by the total tablet weight.
Formulation in the present invention can be manufactured with direct compression method and also with the following methods:
Process I: Spray drying: Active substances are separately disintegrated or dispersed with a binder in a polymer, and then they are subjected to spray-drying process. The obtained particles are mixed with other auxiliary products, a lubricant is added to the mixture, the mixture is blended for a short period, and tablet press process is performed.
Process II: Coacervation: Active substances and polymer are disintegrated with an appropriate solvent. The obtained solution is blended at a certain speed and temperature while a solvent is added to make polymer and active substance precipitate. When necessary, pH regulating substances are used to facilitate precipitation. Polymers coat the active substance while they precipitate and spherical microparticles are obtained during the process. The obtained coated particles are dried and sifted to obtain appropriate particle size distribution. Coated particles are mixed with other excipients in the formula, a lubricant is then added to the mixture, and tablet press process is performed after a short period of blending.
Process III: Hot melt extrusion: Active substances are melted together with a meltable polymer, pass through an extruder, subjected to spherization, and sieved to provide a suitable particle size distribution. The obtained particles are mixed with other excipients in the formulation, a lubricant added to the mixture, and tablet press process is performed after a short period of blending.
Process IV: Dual layer tablet: Active substances are mixed with dispersing agents and filler; granulated with alcoholic/hydroalcoholic binding (polymer) solution, dried, and significantly, sifted. The remaining auxialiary substances in the formulation are separately added to both phases, blended, lubricants are then separately added, and press process is performed in bilayer tablet machine after a short period of blending.
In addition to above-mentioned processes, orally disintegrating tablets can also be produced via pellet coating method. In this method, sugar pellets should also be used in addition to excipients. Hydroalcoholic/alcoholic solutions with PVP of active substances tadalafil and dapoxetine are prepared and sugar pellets are separately coated with these preparations. Polymetachrylate; alcoholic/hydroalcoholic solutions are prepared and sugar pellets containing tadalafil and dapoxetine are separately coated. The obtained tadalafil and dapoxetine pellets are mixed with other excipients in the formulation, a lubricant is than added to the mixture and tablet press process is performed after blending for a short period.
According to a different view, the present invention shows that the disintegration rate of the tablet can be altered substantially by changing the shape and size of the tablet. In general, as the tablet becomes thinner and more porous the orally disintegrating composition will be weakened more rapidly when exposed to saliva because process of disintegration takes place after all surface area of the tablet is moistened by the capillary effect. In addition, any shape maximizing contact surface with saliva can remarkably shorten the period of the disintegration.
The preferred shape of the orally disintegrating tablet composition of this invention may be a disk, a circle, a sphere, a globe, a gobbet, a rod, a polygon, and ellipse. The preferred shape of the tablet is a flat circle.
The invention is explained in detail with the following examples. The examples do not limit the scope of the invention and should be considered in the context of the description detailed above.
Manufacturing method: Direct Compression Method
Tadalafil, dapoxetine, mannitol, and crosspovidon are mixed. Polyvinyl pyrrolidone, calcium silicate, sucralose, and orange aroma are added to this mixture and the mixture is blended until a homogenous mixture is obtained. Sodium stearyl fumarate is added to the final mixture and after blending for a short period, tablet compression process is performed.
Manufacturing Method:
Sildenafil, dapoxetine, mannitol, and a part of crospovidone are mixed, granulated with alcoholic/hydroalcoholic polyvinyl pyrrolidone solution, dried, and sifted. Calcium silicate, the remaining part of crosspovidon, sucralose, and orange aroma are added to this mixture and blended until a homogenous mixture is obtained. Sodium stearyl fumarate is added to the final mixture and tablet compression process is performed after mixing for a while.
Example 3 will be manufactured with the same Method.
Manufacturing Method:
Avanafil, dapoxetine and a part of mannitol is mixed, granulated with alcoholic/hydroalcoholic pullulan solution, dried, and sifted. The obtained granules are coated with alcoholic/hydroalcoholic polyvinyl alcohol solution in a fluidized-bed system. The remaining part of mannitol, heavy magnesium carbonate, sucralose, and orange aroma is added to this mixture and blended until a homogenous mixture is obtained. Sodium stearyl fumarate is added to the final mixture and tablet compression process is performed after mixing for a while.
Examples 5 and 6 will be manufactured with the same method.
Manufacturing Method:
Mirodenafil and dapoxetine are separately coated with alcoholic/hydroalcoholic polyvinyl alcohol solution. Microcrystalline cellulose, mannitol and crosspovidone, calcium silicate, Avicel-CE 15, sucralose, and orange aroma are added to this mixture and blended until a homogenous mixture is obtained. Sodium stearyl fumarate is added to the final mixture and tablet compression process is performed after blending for a while.
Examples 8 and 9 will be manufactured with the same method.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2012/09599 | Aug 2012 | TR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/TR2013/000259 | 8/13/2013 | WO | 00 |
