Process for the preparation of pharmaceutical microcapsules with enhanced taste-masking and high dissolution rate

Abstract

Process for the production of microcapsules containing a drug and comprising a layer of ethylcellulose and a layer of an acrylic polymer and microcapsules produced thereby.

1 . A process for the production of microcapsules containing a drug, comprising the following steps: 
 a. coating drug microparticles with a layer of ethylcellulose    b. further coating the product of a. with a layer of an acrylic polymer.    
     
     
         2 . A process according to  claim 1 , where the coating in step a. is applied by phase separation microencapsulation or by fluidized bed coating.  
     
     
         3 . A process according to  claim 1 , wherein the coating in step b. is applied by spraying a solution of suspension of acrylic polymer onto the particles obtained in a., suspended in a fluidized bed.  
     
     
         4 . A process according to  claim 3 , wherein said solution or suspension is a hydroalcoholic solution, comprising the following weight percentages of components, calculated with respect to the total weight of the solution: 
 acrylic polymer: 4-20%    alcohol: 30-94%    water: 0-40%    micronised inorganic material: 2-20%    
     
     
         5 . A process according to  claim 3 , wherein said hydroalcoholic solution or suspension comprises the following weight percentages of components, calculated with respect to the total weight of the solution: 
 acrylic polymer: 7-20%    alcohol: 40-75%    water: 10-35%    micronised inorganic material: 5-9%    
     
     
         6 . A process according to  claim 4 , wherein said alcohol is ethanol, and said inorganic material is talc.  
     
     
         7 . A process according to  claim 1 , wherein the product of step a. has a drug/ethylcellulose weight ratio (phase ratio) comprised between 1:1 and 30:1, and the product of step b. has an acrylic polymer content comprised between 5% and 40% by weight.  
     
     
         8 . A process according to  claim 1 , wherein the product of step a. has a drug/ethylcellulose weight ratio (phase ratio) comprised between 3:1 and 15:1, and the product of step b. has an acrylic polymer content comprised between 10% and 25% by weight.  
     
     
         9 . A process according to  claim 1 , wherein the taste-masked microcapsules obtained in step b. have a weight median diameter comprised between 20 and 800 μm, drug potency comprised between 400 and 950 mg/g, and are capable of releasing at least 80% of the drug contained therein within 30 minutes in a aqueous acidic media.  
     
     
         10 . Microcapsules containing a drug, obtainable by the process described in  claim 1 .  
     
     
         11 . Microcapsules according to  claim 10 , formulated in a pharmaceutical administrable form.  
     
     
         12 . Microcapsules according to  claim 11 , wherein said pharmaceutical administrable form is chosen from dry powders for extemporaneous suspensions, tablets, minitablets, microcapsule-containing capsules, monodose sachets, fast disintegrating tables, syrups.  
     
     
         13 . Microcapsules according to  claim 10 , wherein said drug is chosen from penicillins, cephalosporins, carbapenem, penems, penams, aminoglycosides, macrolides, ketolides, tetracyclines, quinolones.  
     
     
         14 . A process according to  claim 9  wherein the taste-masked microcapsules obtained in step b. have a weight median diameter comprised between 100 and 400 μM and a drug potency comprised between 400 and 950 mg/g.