Inert core implant pellet

Claim 2

A solid, spherical, subcutaneously implantable pellet for producing a greater than normal weight gain in ruminants, which implantable pellet exhibits a substantially constant rate of release of active agents over a given time period and an abrupt termination of drug release at the end of said time period, said pellet comprising (a) a biocompatible, inert, spherical core having a diameter of about 2 to about 10 mm and (b) at least one biocompatible, biosoluble coating having a substantially uniform thickness of about 0.05 to about 1.0 mm intimately adhering to and completely covering said inert core, the composition of said coating comprising a substantially homogeneous mixture of (i) about 5 to about 90% weight of estradiol, estradiol benzoate, or mixtures thereof as the sole active agent(s), and (ii) about 10 to about 95% weight of a pharmaceutically suitable carrier, said inert, spherical core being at least half the diameter of said spherical, implantable pellet.

Claim 3

The pellet of claim 1 wherein said carrier is chosen from a solid polyethylene glycol having a molecular weight from about 3,000 to about 20,000, cholesterol, or mixtures thereof.

Claim 4

The pellet of claim 1 wherein said core is a biosoluble substance.

Claim 5

The pellet of claim 1 wherein said inert core is cellulose acetate.

Claim 6

The pellet of claim 1 wherein said inert core is a diameter of about 2 to about 3 mm, said coating is about 0.1 to about 0.5 mm thick, and the composition of said coating comprises about 30 to about 90% of said active agent and about 10 to about 70% of said carrier.

Claim 7

A process for administering estradiol, estradiol benzoate, or mixtures thereof to a ruminant over a given period of time to provide a greater than normal weight gain, which process comprises subcutaneously implanting at least one spherical pellet comprising (a) a biocompatible, inert, spherical core having a diameter of about 2 to about 10 mm and (b) at least one biocompatible, biosoluble coating having a substantially uniform thickness of about 0.05 to about 1.0 mm intimately adhering to and completely covering said inert core, the composition of said coating comprising a substantially homogeneous mixture of (i) about 5 to about 90% weight of estradiol, estradiol benzoate or mixtures thereof as the sole active agent(s), and (ii) about 10 to about 95% weight of a pharmaceutically suitable carrier, the diameter of said inert, spherical core being at least half of the diameter of said spherical, implantable pellet, said active agent(s) being released at a substantially constant, weight-gain-producing rate over said given time period, said agent(s) being substantially fully released at the end of said given time period and substantially none of said active agent(s) being released from said pellet after said given time period.

Claim 8

A process for administering estradiol, estradiol benzoate, or mixtures thereof to a ruminant over a given period of time to provide a greater than normal weight gain, which process comprises subcutaneously implanting at least one spherical pellet comprising (a) a biocompatible, inert, spherical core having a diameter of about 2 to about 10 mm and (b) at least one biocompatible, biosoluble coating having a substantially uniform thickness of about 0.05 to about 1.0 mm intimately adhering to and completely covering said inert core, the composition of said coating comprising a substantially homogeneous mixture of (i) about 5 to about 90% weight of estradiol, estradiol benzoate or mixtures thereof as the sole active agent(s), and (ii) about 10 to about 95% weight of a pharmaceutically suitable carrier, the diameter of said inert, spherical core being at least half of the diameter of said spherical, implantable pellet, said active agent(s) being released at a substantially constant, weight-gain-producing rate over said given time period, said agent(s) being substantially fully released at the end of said given time period and substantially none of said active agent(s) being released from said pellet after said given time period.

Claim 9

The process of claim 6 wherein said animal is slaughtered after said given period of time.

Claim 10

The process of claim 7 wherein said inert core is absorbed by the animal prior to slaughtering said animal.

Claim 11

The process of claim 6 wherein said animal is a bovine.

Claim 12

The process of claim 6 wherein said animal is a steer.

Claim 13

The process of claim 6 wherein said animal is a calf.

Claim 14

The composition of claim 5 wherein said coating comprises 30 percent polyethylene glycol 6000, 10 percent cholesterol and 60 percent estradiol benzoate.