Pharmaceutical preparation containing copolyvidone

1. A coated tablet for stabilizing (S)—N-[2-(1,6,7,8-tetrahydro-2H-indeno[5,4-b]furan-8-yl)ethyl]propionamide (Compound A) or a pharmaceutically acceptable salt thereof comprising:

a plain tablet comprises:

Compound A or a pharmaceutically acceptable salt thereof;

an excipient wherein the excipient is one or more selected from the group consisting of lactose, corn starch and hydroxypropylcellulose;

and further

a lubricant, wherein the lubricant is magnesium stearate; and

a copolyvidone-containing coating agent, free from polyethylene glycol (PEG) with which the plain tablet is coated, which comprises a water-soluble, film-coating base, wherein the water-soluble film-coating base is hydroxypropylymethylcellulose,

copolyvidone,

a light-protecting agent, wherein the light-protecting agent is titanium oxide,

and further

a colorant, wherein the colorant is yellow iron oxide wherein the amount of decomposition produces in the coated tablet, as measured using high performance liquid chromatography (HPLC), is less than the amount of decomposition products in an analogous tablet, as measured using HPLC, the analogous tablet comprising an identical amount by weight of polyethylene glycol 6000 (PEG 6000) instead of copolyvidone, after storage of the coated tablet and the analogous tablet under similar storage conditions.

2. The coated tablet according to claim 1 , wherein:

the coating agent is soluble in water;

the plain tablet comprises from about 0.3 mg to about 10 mg Compound A or a pharmaceutically acceptable salt thereof;

the plain tablet further comprises a binder;

and/or

the water-soluble, film-coating base comprises hydroxypropylmethylcellulose 2910.

3. A method selected from the group consisting of:

a method for stabilizing (S)—N-[2-(1,6,7,8-tetrahydro-2H-indeno[5,4-b]furan-8-yl)ethyl]propionamide (Compound A) or a pharmaceutically acceptable salt thereof, which comprises coating a plain tablet comprising Compound A or the pharmaceutically acceptable salt thereof;

an excipient wherein the excipient is one or more selected from the group consisting of lactose, corn starch and hydroxypropylcellulose;

and further

a lubricant, wherein the lubricant is magnesium stearate;

with a polyethylene glycol (PEG)-free, copolyvidone-containing coating agent comprising a water-soluble, film-coating base, wherein the water-soluble, film-coating base is hydroxypropylmethylcellulose, copolyvidone,

a light-protecting agent, wherein the light-protecting agent is titanium oxide,

and further

a colorant, wherein the colorant is yellow iron oxide;

wherein the amount of decomposition products in the coated tablet, as measured using high performance liquid chromatography (HPLC), is less than the amount of decomposition products in an analogous tablet, as measured using HPLC, the analogous tablet comprising an identical amount by weight of polyethylene glycol 6000 (PEG 6000) instead of copolyvidone, after storage of the coated tablet and the analogous tablet under similar storage conditions.

4. A method of treating or alleviating a biological rhythm disorder comprising administering to a patient in need thereof an effective dose of (S)—N-[2-(1, 6, 7, 8-tetrahydro-2H-indeno[5, 4-b]furan-8-yl)ethyl]propionamide (Compound A) or a pharmaceutically acceptable salt thereof in the coated tablet of claim 1 .

5. The method of claim 4 , wherein:

the biological rhythm disorder is a melatonin-influenced disorder;

the biological rhythm disorder comprises dysgryphia, a sleep-awakening rhythm disorder, jet lag, or time-zone syndrome; and/or

the plain tablet comprises from about 0.3 mg to about 10 mg Compound A or a pharmaceutically acceptable salt thereof.

6. The method of claim 3 , wherein the plain tablet comprises from about 0.3 mg to about 10 mg Compound A or a pharmaceutically acceptable salt thereof.

7. The method of claim 3 , wherein:

the plain tablet comprises from about 0.3 mg to about 10 mg Compound A or a pharmaceutically acceptable salt thereof;

the plain tablet further comprises a binder;

the coating agent is soluble in water; and/or

the water-soluble, film-coating base comprises hydroxypropylmethylcellulose 2910.

8. The method of claim 3 , wherein the amount of decomposition products in the analogous tablet is at least twice as much as the amount of decomposition products in the coated tablet after storage of the coated tablet and the analogous tablet for about 4 weeks.

9. The method of claim 3 , wherein the amount of decomposition products in the analogous tablet is at least three times as much as the amount of decomposition products in the coated tablet after storage of the coated tablet and the analogous tablet for about 4 weeks.

10. The method of claim 3 , wherein the content of Compound A in the coated tablet, as measured using high performance liquid chromatography (HPLC), is substantially the same after storage of the coated tablet as the content of Compound A in the coated tablet prior to storage.

11. The coated tablet according to claim 1 , wherein the plain tablet comprises from about 0.3 mg to about 10 mg of Compound A, and the water-soluble, film-coating base is hydroxypropylmethylcellulose 2910.

12. The coated tablet of claim 1 , wherein the amount of decomposition products in the analogous tablet is at least twice as much as the amount of decomposition products in the coated tablet after storage of the coated tablet and the analogous tablet for about 4 weeks.

13. The coated tablet of claim 1 , wherein the amount of decomposition products in the analogous tablet is at least three times as much as the amount of decomposition products in the coated tablet after storage of the coated tablet and the analogous tablet for about 4 weeks.

14. The coated tablet of claim 1 , wherein the content of Compound A in the coated tablet, as measured using high performance liquid chromatography (HPLC), is substantially the same after storage of the coated tablet as the content of Compound A in the coated tablet prior to storage.

15. The coated tablet of claim 2 , wherein the content of Compound A in the coated tablet, as measured using high performance liquid chromatography (HPLC), is substantially the same after storage of the coated tablet as the content of Compound A in the coated tablet prior to storage.