Enteric coated tablet and process for making

• US 4,775,536 A
• Filed: 02/24/1986
• Issued: 10/04/1988
• Est. Priority Date: 02/24/1986
• Status: Expired due to Term

• Current Assignee: Bristol-Myers Squibb Company
• Original Assignee: Bristol-Myers Squibb Company
• Inventors: Patell, Mahesh K.
• Primary Examiner(s): Page, Thurman K.
• Application Number:
  US06/832,839
• Time in Patent Office: 953 Days
• Field of Search: 427/3, 424/482, 424/471, 424/480
• US Class Current: 424/471
• CPC Class Codes: A61K 31/60 Salicylic acid; Derivatives thereof
• CPC Class Codes: A61K 9/2886 having two or more different drug-free coatings; Tablets of the type inert core-drug layer-inactive layer of the type active core-drug layer-inactive layer A61K9/209

Abstract

An enteric coated tablet and process is described in which a core tablet of a pharmaceutically active ingredient is provided with an enteric coating layer of a film forming enteric polymer and an overcoat layer of non-enteric film forming polymer; optionally, the tablet may also be provided with the non-enteric undercoat layer of a film forming polymer.

Claims

1. An enteric coated tablet comprising a tablet core containing aspirin as an active ingredient, an enteric coat layer encompassing said tablet core, and an overcoat layer encompassing said enteric coat layer, said enteric coat layer comprising a water soluble or water dispersible enteric film forming polymer and said overcoat layer comprising a non-enteric water soluble or water dispersible film forming polymer, said tablet also being provided with an undercoat layer disposed beneath said enteric coat layer, said undercoat layer also comprising a non-enteric water soluble or water dispersible film forming polymer.

2. An enteric coated tablet according to claim 1 wherein said tablet can withstand agitation in a basket at 100 rpm in artificial gastric juice having a pH of 1.2 at a temperature of 37°

C. releasing less than 10% aspirin in two hours while dissolving not less than 85% aspirin in 90 minutes in artificial intestinal fluid having a pH of 6.8 at a temperature of 37°

C.

3. An enteric coated tablet according to claim 2 wherein said the water soluble or water dispersible film forming enteric polymer is an acrylic resin.

4. An enteric coated tablet according to claim 3 wherein said water soluble or water dispersible film forming enteric polymer is a copolymer that is anionic in character and based on polymethylacrylic acid and acrylic acid esters.

5. An enteric coated tablet according to claim 4 wherein said film forming enteric polymer is of the formula ##STR2## wherein n is a whole number, R is H or CH₃, and R₁ is CH₃ or CH₂ H₅ --, the ratio of free carboxyl groups to ester groups being about 1:

1 and the mean molecular weight of said polymer being about 250,000.

6. An enteric coated tablet according to claim 3 wherein the said water soluble or water dispersible non-enteric polymers of said overcoat layer and said undercoat layer are the same or different and is one of the following polymers:

hydroxypropylmethylcellulose, polyvinylpyrrolidone, hydroxypropylcellulose, polyethyleneglycol, methylcellulose, or pseudoethylcellulose.

7. An enteric coated tablet according to claim 4 wherein the said water soluble or water dispersible non-enteric polymers of said overcoat layer and said undercoat layer are the same or different and is one of the following polymers:

hydroxypropylmethylcellulose, polyvinylpyrrolidone, hydroxypropylcellulose, polyethyleneglycol, methylcellulose, or pseudoethylcellulose.

8. An enteric coated tablet according to claim 5 wherein the said water soluble or water dispersible, non-enteric polymers of said overcoat layer and said undercoat layer are the same or different is one of the following polymers:

hydroxypropylmethylcellulose, polyvinylpyrrolidone, hydroxypropylcellulose, polyethyleneglycol, methylcellulose, or pseudoethylcellulose.

9. An enteric coated tablet according to claims 1, 2, 3, 4, 5, 6, 7 or 8 wherein said

(a) said undercoat layer, when present comprises from about 0% to about 3% by weight based on the total weight of said enteric coated tablet,

(b) said enteric coat layer comprises from about 4% to about 6% by weight based on the total weight of said enteric coated tablets, and

(c) said overcoat layer comprises from about 1% to about 3% by weight based on the total weight of said enteric coated tablet.

10. A process for preparing an enteric coated tablet which comprises applying to a tablet core containing aspirin as an active ingredient an undercoat layer comprising a non-enteric water soluble or water dispersible film forming polymer to form an under-coated aspirin containing tablet core, applying to said under-coated tablet core an intermediate enteric coat layer encompassing said under-coated tablet core and then applying an overcoat layer encompassing said enteric coat layer, said enteric coat layer comprising a water soluble or water dispersible film forming enteric polymer and said overcoat layer comprising a non-enteric water soluble on water dispersible film forming polymer.

11. A process according to claim 10 wherein said resulting tablet can withstand agitation in a basket at 100 rpm in artificial gastric juice having a pH of 1.2 at a temperature of 37°

C. releasing less than 10% aspirin in two hours while dissolving not less than 85% aspirin in 90 minutes in artificial intestinal fluid having a pH of 6.8 at a temperature of 37°

C.

12. A process according to claim 11 wherein said water soluble or water dispersible film forming enteric polymer is an acrylic resin.

13. A process according to claim 12 wherein said water soluble or water dispersible film forming enteric polymer is a copolymer that is anionic in character and based on polymethylacrylic acid and acrylic acid esters.

14. A process according to claim 13 wherein said film forming enteric polymer is of the formula ##STR3## wherein n is a whole number, R is H or CH₃ and R₁ is CH₃ or C₂ H₅, the ratio of free carboxyl groups to ester groups being about 1:

1 and the mean molecular weight of said polymer being about 250,000.

15. A process according to claim 14 wherein the said water soluble or water dispersible non-enteric polymer of said overcoat layer and said undercoat layer are the same or different and is one of the following polymers:

hydroxypropylmethylcellulose, polyvinylpyrrolidone, hydroxypropylcellulose, polyethyleneglycol, methylcellulose, or pseudoethylcellulose.

16. A process according to claims 10, 11, 12, 13, 14, or 15 wherein

(a) said undercoat layer when deposited comprises from about 2% to about 3% by weight based on the total weight of said enteric coated tablet,

(b) said enteric coat layer comprises from about 4% to about 6% by weight based on the total weight of said enteric coated tablets, and

(c) said overcoat layer comprises from about 2% to about 3% by weight based on the total weight of said enteric coated tablet.