Patent Application
20110212182
The present invention relates to coated granules and granulates. It also relates to pharmaceutical presentations incorporating said coated granules or granulates.
The administration of solid oral forms such as tablets may prove to be dangerous, particularly for children and the elderly, who prefer chewable tablets, tablets that dissolve in the mouth or in a spoon or water, granules, powders, solutions or suspensions.
A number of active ingredients have an unpleasant taste, such that it is essential to mask their taste. Taste masking is defined as any method making it possible to delay or prevent the occurrence of an unpleasant taste specific to a product during its oral, buccal or nasal administration.
In the case of pharmaceutical formulations administered in dry forms, such as tablets, said masking must be maintained for at least the time that the product remains in the oral cavity, in order to improve comfort and optimize observance of the treatment by the patient.
In the case of formulations administered in liquid form, formulations packaged in multi-dose vial forms, particularly in the case of dry suspensions intended for extemporaneous reconstitution, also referred to as dry suspension for reconstitution, the lack of bitterness must be maintained for a time equivalent either to the treatment time or to the duration of the use of the vial. Therefore, the active granule or granulate used in such formulations should be stable in contact with an aqueous liquid phase for a period at least equal to 24 hours. In practice, this involves preventing the solubilisation of the active ingredient in the liquid phase.
In general, taste masking is carried out by encapsulating the active ingredient inside a capsule or by means of microencapsulation techniques wherein polymeric coating is applied to the active ingredient (WO 92/11871).
One of the solutions proposed consists of coating the active ingredient particles with a cellulose polymer. Said polymers particularly include ethylcellulose and hydroxypropylmethylcellulose.
Another solution consists of coating the active ingredient particle with an acrylic type polymer. Of said polymers, a distinction is made between pH-dependent polymers, i.e. polymers wherein the solubility depends on the pH and insoluble polymers Wherein the intrinsic properties are not influenced by the pH of the medium.
However, even if the taste of the active ingredient present in the granules is masked in a satisfactory manner, said polymers interfere with the release of the active ingredient and require the use of agents favouring or delaying the solubilisation of the active ingredient (GB 1 511 85; WO 91/16043).
In addition, conventional techniques and formulas, although they provide satisfactory taste masking, do not make it possible to obtain stable membranes in suspension for more than one day.
Matrix microspheres have also been stabilised, but they require additional coating to achieve the desired stability; acceptable stability can be obtained in an acidic pH with cellulose acetates, but a delay in the release is observed (EP 0 293 885).
Therefore, there is still a great need to have a formulation enabling a rapid or controlled release of the active ingredient in a physiological medium, without said active ingredient being released in the formulation medium, which offers sufficient stability, i.e. an ability to retain the masking of the taste for a period at least equal to 24 hours.
The inventors surprisingly found that a granule or granulate comprising, firstly, a core containing an active ingredient possibly associated with at least one waxy compound and at least one polymer and, secondly, at least three coating layers, wherein the second contains at least one waxy compound, makes it possible to isolate the active ingredient for a sufficient time to ensure the stability of the masking of the taste when the dry suspension incorporating said coated granule or granulate is reconstituted by adding a defined volume of water when the first dose is administered. After administration, it is possible to have either an immediate release or a modified, i.e. delayed or sustained, release of the active ingredient.
Consequently, one of the aims of the present invention is to solve the problems, or at least improve the solutions implemented in the prior art to compensate for the difficulties in the development of this type of formulation.
Therefore, the present invention relates to coated granules and granulates characterised in that they comprise:
Within the scope of the present invention, the term immediate release refers to a release wherein the kinetics is not substantially modified by the formulation and/or by the parameters of the manufacturing method, which means that the dissolution profile of the active ingredient depends essentially on its intrinsic properties. On the other hand, the term modified release refers to a release wherein the kinetics is substantially modified by the formulation and/or by the parameters of the manufacturing method.
Within the scope of the present invention, the term complementary release function refers to a release of the same type as that obtained with the coating 1.
Within the scope of the present invention, conditioning the suspension medium signifies that the characteristics of the reconstituted suspension, obtained from excipient grains, are selected according to the release profile of the coated active granule or granulate, in vitro or after administration of said reconstituted suspension.
In a particular embodiment of the invention, additional layers may be applied wherein the composition is identical to that of layers 1 and 3.
An outer coating intended to mask any bitterness related to the constituents of the third coating layer 3, which does not modify the release properties of the coated granule and granulate substantially may be applied.
In a particularly advantageous embodiment of the invention, the core is a preferentially neutral substrate of determined grain size, based on starch, sucrose, ethylcellulose, lactose and wax, whereon the active ingredient is applied in a layer by atomising a suspension or a solution of said active ingredient, in an aqueous, organic solvent or in a mixture in the presence of at least one binding agent or at least one polymer or at least one waxy compound or a mixture of at least two of said agents and lubricants, if applicable.
In another advantageous embodiment of the invention, the core is the active ingredient itself, in the form of a spherical crystal or not, if its grain size allows effective direct coating. Otherwise, layer application (assembly) of the active ingredient should be carried out by atomising a solution or a suspension of said active ingredient in the presence of least one binding agent or at least one polymer or at least one waxy compound or a mixture of at least two of said agents and lubricants, if applicable, and organic solvents or water.
In another particularly advantageous embodiment of the invention, the core is a granulate based on the active ingredient obtained by granulation. The granulate may be obtained by wet granulation or in a fluidised air bed, or by spherical crystallisation or by emulsion-diffusion of solvent preferentially using (a) solutions of granulations based on organic solutions of waxy compound(s) in the presence of lubricants and plasticisers or (b) a polymer such as hydroxypropylmethylcellulose. In addition, assembly of the active ingredient may be carried out using said granulate as a substrate, by atomising a solution or suspension of active ingredient in organic solvents or in water, in the presence of at least one binding agent or at least one polymer or at least one waxy compound or a mixture of at least two of said agents and lubricants, if applicable.
In addition to the active ingredient, the core may contain various agents; these agents include insoluble agents, particularly talc, silicone dioxide, titanium dioxide, silica, alumina, starch and mixtures thereof; they also include soluble agents, particularly mannitol, sucrose, lactose, dextrose, sodium chloride, sorbitol and mixtures thereof, polyethylene glycol or amphiphilic compounds (magnesium stearate, polysorbates).
The core may contain up to 100% active ingredient, preferentially between 30 and 85% according to the dosage of the final formulation and the proportion of dry content to obtain a homogeneous suspension.
The core containing the active ingredient may have any suitable size, but preferentially the size distribution of the core containing the active ingredient has a mean between 100 and 500 μm, the mean being preferentially between 100 and 250 μm when the core is a granulate or the active ingredient itself, and preferentially between 400 and 500 μm when the core is a neutral substrate whereon the active ingredient is applied in a layer.
As active ingredients, it is particularly possible to use, without this list being restrictive: antacids, anti-inflammatories, coronary or peripheral vasodilators, anti-infectious agents, antibiotics, antiparasitics, anxiolytics, psychotropic agents, neuroleptics, central nervous system stimulants, antihistamines, antidiarrhoeals, nutritional supplements, antivirals, antispasmodics, vasoconstrictors, antithrombotics, antimigraine agents, analgesics, antipyretics, antiasthmatics, antitussives, mucoregulators, decongestants, plant extracts and antinauseants.
Preferentially, the active ingredient is an anti-infectious substance, selected from the macrolides.
The latter particularly include erythromycin and its derivatives, and clarithromycin.
According to the invention, the coatings 1 and 3 are functional coatings, wherein the purpose is to provide an active ingredient release property, that is immediate, sustained or delayed; they consist of polymers conventionally known to those skilled in the art to provide said properties possibly associated with a waxy compound. Delayed-release polymers particularly include: polymethacrylates particularly those marketed under the name Eudragit®L, Eudragit®S and Eudragit® FS30D, cellulose acetophthalate and cellulose acetate; sustained-release polymers include: polymethacrylates particularly those marketed under the name Eudragit® NE, Eudragit®RS and Eudragit®RL, ethyl cellulose, polyvinyl acetate, polyvinyl alcohol and copolymers thereof; immediate-release polymers include: polymethacrylates particularly those marketed under the name Eudragit®E.
The waxy compounds used may particularly be selected from the group consisting of: waxes, Novata® waxes, gelucires and suppocires, glycerol macrogols, fatty acids (stearic acid), fatty acid esters, glycerol monostearate Precirol®, Compritol®.
Of these waxy compounds, hydrophobic waxy compounds are advantageously used and hydrophobic waxy compounds with a low HLB (hydrophilic-lipophilic balance) and with a melting point between 35 and 53° C., preferentially between 37 and 43° C., even more advantageously. These include, in a non-restrictive manner, the waxy compounds marketed under the names Gelucire® 43/01 and Novata®AB.
These waxy compounds may be associated with glycerol monostearate (GMS).
In this way, if an immediate release is desired, it is possible to use as functional coatings 1 and 3, a coating consisting advantageously of a mixture of Eudragit® E100 and possibly hydrophobic waxy compounds with a low HLB (hydrophilic-lipophilic balance) and with a melting point between 35 and 53° C., preferentially between 37 and 43° C. in the presence of lubricants. These include, in a non-restrictive manner, Gelucire® 43/01 and Novata®AB, possibly associated with glycerol monostearate (GMS).
If a delayed release is desired, it is possible to use as functional coatings 1 and 3, a coating based on an aqueous dispersion or an organic solution of Eudragit® L in the presence of hydrophobic plasticisers and lubricants.
If a modified release is desired, the functional coatings 1 and 3 may be based on an aqueous dispersion or an organic solution of ethylcellulose or Eudragit® RL or RS or a coating based on an organic solution of said polymers or Eudragit® S in the presence or not of waxy compounds and/or lubrication agents, plasticisers and lubricants.
The coating contents for the coating 1 (calculated as a percentage (w/w) of dry content applied to the initial substrate) is advantageously between 5 and 100% and preferentially between 30 and 60%.
The purpose of the hydrophobic coating 2 is to increase the stability of the suspended grain. It consists of a waxy compound solution base in a solvent and possibly comprises a lubrication agent such as, for example, talc, hydrophobic colloidal silica or glycerol monostearate (GMS). The coating content for said second coating (calculated as a percentage (w/w) of dry content applied to the initial substrate) is advantageously between 5 and 100% and preferentially between 20 and 80%.
In this way, this hydrophobic coating 2 advantageously comprises a waxy compound or a combination of low-HLB hydrophobic waxy compounds and with a melting point between 35 and 53° C., preferentially 37 and 43° C. in a solvent. This particularly includes Gelucire® 43/01, Gelucire® 53/01, Novata® AB, glycerol monostearate and mixtures thereof.
The polymeric function coating 3 which has complementary release functions to those of the coating 1 is either identical or analogous to said coating 1, but has the same properties with respect to the release of the active ingredient and conditions the suspension medium. The coating content on said coating 3 (calculated as a percentage (w/w) of dry content applied to the initial substrate) is advantageously between 5 and 200% and preferentially between 80 and 160%.
If the coating 3 has a strong taste due to the excipients comprised therein, then an outer coating based on Eudragit® RL30D and RS30D or mixtures thereof, in the presence of plasticisers and lubricants, is applied. The coating content at this level will advantageously be between 0 and 15% and preferentially between 0 and 5%.
The lubrication agents (lubricant agents) are advantageously selected from the group comprising talc, hydrophobic colloidal silica and glycerol monostearate.
The plasticisers are advantageously selected from the group consisting of dibutylsebaccate, triethylcitrate, diethylphthalate, acetyltriethylcitrate, acetyltributylcitrate, glycerol monostearate (GMS) and Myvacet®.
The coated granules and granulates according to the invention are prepared according to a method which comprises the production of the core or substrate and possibly includes an additional assembly step.
The method may advantageously comprise the following steps:
The coating solvents are those conventionally used by those skilled in the art. For example, these include water, methylene chloride, ethanol, isopropanol and mixtures thereof.
Said method is carried out in a fluidised air bed or by means of any other similar industrial method known to those skilled in the art.
The drying operation may be carried out in a fluidised air bed, in a vacuum rotary drier or by means of any equivalent technique enabling the removal of the residual solvents.
According to an advantageous embodiment of the invention, the method also comprises the application of additional layers identical to the layers 1 and 3 and essentially the application of an outer coating aiming to mask the taste of the constituents of the preceding coating.
The coated granules and granulates according to the invention may be used in any suitable pharmaceutical formulation enabling immediate reconstitution in a liquid medium. They may particularly be used to prepare dry syrups, tablets, sachets and suspensions. Of said suspensions, dry suspensions for reconstitution, i.e. powders packaged in multi-dose vials which can be reconstituted before use as a suspension in a liquid such as water, should advantageously be selected.
The powders for reconstitution prepared from granules and granulates according to the invention are stable during storage and the suspensions, once reconstituted in the multi-dose vial, have a masked taste for the duration of the treatment or, if the treatment requires several vials, for the duration of the use of the vial. In any case, the reconstituted suspension is stable for at least 24 hours. These suspensions also have a sufficient bioavailability and are particularly useful in pediatric and geriatric treatments.
The invention also relates to a dry suspension for reconstitution containing granules or granulates according to the invention.
In said formulation, the active grain gives the suspension its taste masking and release properties.
This dry suspension for reconstitution also contains excipients giving the reconstituted formulation particular organoleptic characteristics and also microbiological stability.
These excipients are selected from those conventionally used by those skilled in the art to produce said formulations. These excipients include sweeteners, colorants, viscosity agents or thickeners, pH-modulating agents, preservatives (antimicrobial or fungicidal), surfactants and antioxidants.
This suspension may be obtained in several ways:
In addition, the invention also relates to a dry mixture comprising granules or granulates according to the present invention associated with any suitable excipient to obtain a dry suspension for reconstitution in a liquid medium wherein at least one is a thickening agent, one is a preservative and one is a pH-modulating agent.
Examples of thickeners include all the thickeners known to those skilled in the art, particularly those selected from the group comprising gums such as xanthan, guar and traganth, magnesium silicate and combinations thereof, sodium alginate, propylene glycol alginate, cellulose compounds such as hydroxyethyl cellulose, hydroxypropyl cellulose, methyl cellulose, carboxymethyl cellulose, carbomers, gelatine, poloxamers, or combinations of these compounds and carrageenans.
Examples of pH-adjusting agents advantageously include those selected from the group comprising citric acid, soda, sodium citrate, trisodium citrate or any other pharmaceutically acceptable compound having the ability to buffer an aqueous solution.
Examples of preservatives include those selected from the group comprising potassium or sodium sorbate, sodium benzoate, azorubin, bronopol, ethylene diamine tetra-acetic acid (EDTA), methyl, ethyl, propyl and butyl p-hydroxybenzoate (parabens) and salts thereof, used alone or in a mixture, propionic acid, sulphites and cresol.
The suspension may also contain one or more sweeteners such as saccharin salts and/or potassium acesulfam, or any other sweetener known to those skilled in the art such as aspartame, sucrose and its derivatives, trehalose, sodium glycyrrhizinate or mixtures thereof, an opacifying agent such as Opadry® OYB or titanium oxides and product capture agents such as cyclodextrins wherein the quantities are adapted according to the size of the molecule and the function to be isolated.
The suspension may also contain one or more aromatic compositions and a filling agent, particularly polyols, for example sorbitol (Neosorb®), xylitol and lactitol.
The excipient grain may be obtained by means of a wet granulation method or any other similar industrial method known to those skilled in the art. It may also be obtained by producing a hydro-alkanol solution of the sweeteners and/or preservatives to be used as a wetting solution with a mixture of filling agents such as sorbitol, thickening agent, opacifying agent, pH-adjusting agent, aromatic formulations if applicable, the purpose of the filling agent being to create a sufficient mass for the granulation. Any other excipient fulfilling the same function may also be used.
Another alternative consists of assembling the excipients on the active grain by any technique known to those skilled in the art, particularly in a fluidised air bed.
When the first dose of medicinal product is administered, the suspension is prepared by adding a defined quantity of water (for example, by volume, or using a mark on the vial), directly into the vial containing the final dry mixture.
The excipient grains prepared in this way enable rapid reconstitution of the suspension, which only requires manual stirring by turning to homogenise the preparation; in addition, the suspension obtained has a good bacteriological stability and masking stability of over 7 days, independent of the pH of the suspension. It is particularly useful in pediatric and geriatric treatments.
The pH of the suspension is adjusted according to the properties of the coated granule or granulate to be associated.
If an immediate release is desired, the pH of the suspension should be between 5.5 and 10, preferentially between 8.5 and 10. For a delayed release, the pH of the suspension should be between 3 and 7, preferentially between 4 and 5.
Due to the presence of waxy agents, the masking stability of the suspensions is enhanced. The waxy agents also make it possible to reduce the quantity of polymers used for the coating and therefore the toxicity induced by said polymers.
The invention and the advantages it offers will be seen more clearly using the examples of embodiments given below.
1.1 Active grain preparation: since the CHL 13.05 used has a fine grain size distribution, granulation followed by assembly will be carried out.
Step 0: a mixture of powders was produced and placed in the fluidised air bed vessel:
CHL 13.05: 71.4%
Aerosil® R972: 7.1%
Talc M 10: 21.5%
Step 1a: granulation
A solution based on Gelucire® 43/01—Aerosil® R 972 (81%—19%) in methylene chloride is atomised onto the powder mixture.
The dry concentration in methylene chloride is equal to 10% by weight and the dry atomised/substrate ratio is equal to 37.5% by weight.
Step 1b: assembly
A solution based on CHL 13.05—Gelucire® 43/01—Talc M 10 (51.7%—34.5%—13.8%) in a methylene chloride—ethanol mixture (77.9%—22.1% by weight) is atomised onto the granulate obtained in step 1a.
The dry concentration in methylene chloride-ethanol is equal to 11.9% by weight and the dry atomised/substrate ratio is equal to 100% by weight.
Step 2: coating 1=polymeric functional coating
A solution based on Eudragit® E 100—Gelucire® 43/01—Talc M (10/1) (51.4%—5.7%—42.9%) is atomised onto the granulate obtained in step 1b.
The dry concentration in methylene chloride is equal to 12.9% by weight and the dry atomised/substrate ratio is equal to 52.5% by weight.
Step 3: Coating 2=hydrophobic coating
A solution based on Gelucire® 43/01—Talc M 10 (57.1%—42.9%) in methylene chloride is atomised onto the granulate obtained in step 2.
The dry concentration in methylene chloride is equal to 18.2% by weight and the dry atomised/substrate ratio is equal to 35% by weight.
Step 4: coating 3=polymeric functional coating
A solution based on Eudragit® E 100—Gelucire® 43/01—Talc M (10/1) in a methylene chloride water (10/1) mixture is atomised onto the granulate obtained in step 3.
The dry concentration in methylene chloride is equal to 12.9% by weight and the dry atomised/substrate ratio is equal to 105% by weight.
30% of excipient grains and 70% of active grains are introduced into the final packaging (by mixing followed by single feeding or double feeding with no prior mixing). The vial is filled according to the dose of CHL 13.05 administered for the treatment. At the moment of use, fill up to the mark with mineral water. The reconstituted suspension is stable for at least 7 days.
Step 1; the grain constitution steps are similar to those in the previous example.
Step 2: coating 1=polymeric functional coating
A solution based on Eudragit® L30D (dry extract)—Myvacet 9.45—Talc M 10 (77%—11.5%—11.5%) diluted in purified water is atomised onto the granulate obtained in step 1.
The dry concentration in total water is equal to 32.6% by weight and the dry atomised/substrate ratio is equal to 39% by weight.
Step 3: Coating 2=hydrophobic coating
A solution based on Gelucire® 43/01—Talc M 10 (57.1%—42.9%) in methylene chloride is atomised onto the granulate obtained in step 2.
The dry concentration in methylene chloride is equal to 19.4% by weight and the dry atomised/substrate ratio is equal to 35% by weight.
Step 4: coating 3=polymeric functional coating
A solution based on Eudragit® L30D (dry extract)—Myvacet 9.45—Talc M 10 (71.4%—10.7%—17.9%) diluted in purified water is atomised onto the granulate obtained in step 3.
The dry concentration in total water is equal to 34.5% by weight and the dry atomised/substrate ratio is equal to 154% by weight.
Step 5: outer coating
A solution based on Eudragit® S100—Myvacet 9.45—Talc M 10 (83.3%—8.3%—8.3%) in ethanol is atomised onto the granulate obtained in step 4.
The dry concentration in ethanol is equal to 9.8% by weight and the dry atomised/substrate ratio is equal to 0.6% by weight.
The mixture consists of 75% excipient grains and 25% active grains and is then treated as for the previous example.
The stability of the granulates prepared according to the procedure in examples 1 and 2 is evaluated in terms of degradation products, dissolution kinetics, taste and residual solvents.
The stability of the suspensions obtained from granulates prepared according to the procedure in examples 1 and 2, is evaluated in terms of pH, taste masking and released active ingredient assay.
The results are contained in the table below:
The above table shows that:
| Number | Date | Country | Kind |
|---|---|---|---|
| 01/03235 | Mar 2001 | FR | national |
| PCT/FR02/00836 | Mar 2002 | FR | national |
This application is a continuation application of U.S. patent application Ser. No. 10/471,234, filed Jun. 22, 2004, which claims priority under 35 U.S.C. §119 of FR 01/03235, filed Mar. 9, 2001, and is a National Stage Application of PCT/FR02/00836, filed Mar. 8, 2002 and designating the United States (published in the French language on Sep. 19, 2002 as WO 02/072072 A2; the title and abstract were also published in English), each hereby expressly incorporated by reference in its entirety and each assigned to the assignee hereof.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10471234 | Jun 2004 | US |
| Child | 13104513 | US |
