NZ215730A - Sustained-release peptide compositions containing proteins as carriers - Google Patents

Description

N.Z.No.

NEW ZEALAND Patents Act 1953 COMPLETE SPECIFICATION SUSTAINED-RELEASE PREPARATION We, SUMITOMO PHARMACEUTICALS COMPANY LIMITED of 40, Dosho-« machi 2-chome, Higashi-ku, Osaka-shi, Osaka-fu, Japan, cx JCc^p^y, do hereby declare the invention, for which we pray that a Patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement : - (Followed by 1A) 21573 -1ft - SUSTAINED-RELEASE PREPARATION The present invention relates to a sustained-release preparation. More particularly, it relates to a long-term sustained-release preparation of a peptide having a growth promoting activity or an activity relating to bony metabolism which can maintain the clinically effective level of said peptide for a long period of time.

Recently, there has actively been studied as to peptides having a growth promoting activity or an activity relating to bony metabolism in human and other animals, and with progress of the study In the mechanism of said activities, it is aware that it is essential to study the manner of administration of said medicaments.

For instance, it is known that human growth hormone (HGH) is useful for the treatment of pituitary dwarfism, and the hormone is now widely used. For the treatment of this disease, it is important to find the disease a3 early as possible and to start the treatment as early as possible and further to continue the administration of a large amount of HGH until stop of increase in stature due to close of epiphyseal line. However, it is very troublesome to administer so frequently the medicament for a long period of time, and hence, it has been desired to develop a new type of preparation which can release the active medicament for a long period of time. That is, it 21573 has been desired to develop a sustained-release preparation which can continuously release an active substance in a clinically effective amount for a long period of time and can optionally retained in desired region within the body.

The present inventors have intensively studies on an improved sustained-release preparation and have found that the desired sustained-release preparation can be obtained by carrying the active ingredient on a carrier selected from one or more proteins (e.g. collagen, gelatin, albumin, etc.).

An object of the present invention is to provide an improved sustained-release preparation of a peptide having a growth promoting activity or an activity relating to bony metabolism. Another object|-©d of the invention is to provide a sustained-release preparation of the peptide as set forth above in the form of an injectable suspension. A further object of the invention is to provide a sustained-release preparation in the form of a solid preparation.

These and other objects and advantages of the invention will be apparent to persons skilled in the art from the following description.

The sustained-release preparation of the present invention comprises an effective amount of an active peptide in admixture with a carrier selected from one or more proteins such as collagen, gelatin, albumin, or a mixture thereof. More specifically, the preparation is in the form 215730 © - 3 - of an injectable suspension which is prepared by admixing the active ingredient with one or more of the proteins, pulverizing the composite, and suspending the powder into a solution for injection, or in the form of a solid preparation which can be injected, inserted or implanted into the body.

The peptides having a growth promoting activity include growth hormone (GH), growth hormone releasing factor (GRF) and somatomedin (SM). GRF is a peptide which has an activity for releasing growth hormone and there are known various peptides consisting of a number of amino acids of 1*1, JlO, 37 or 29. All of these peptides show the growth hormone releasing activity and these and a mixture thereof are included in the present invention. SM means all of the somatomedin group, such as SM-A, SM-B, SM-C and further insulin-like growth factor (IGF)-I, IGF-II as well as MSA (multiplication stimulating activity). It is reported that SM-C is the same as IGF-I. Anyway, all of these peptides or a mixture of two or more thereof are used in the present w invention.

The peptide having an activity relating to bony metabolism includes, for example, calcitonin (i.e. calcium regulating hormone secreted from the mammalian thyroid gland ^ and in non-mammalian species from the ultimobranchial gland). y These GH, GRF, SM and calcitonin used in the 215730 present invention include all of the products regardless the processes for the preparation thereof, for instance, products Isolated from organisms, artificially synthesized products, and products obtained by genetic engineering technique.

The active ingredients may be used alone or in combination of two or more thereof.

The carrier includes all proteins as mentioned above, but is preferably collagen, gelatin or a mixture thereof in view of moldability thereof. Collagen is a protein which is a main protein of connective tissue of animals and has less antigenicity, and hence, has widely been used as a safe operation yarn in various medical operations. The collagen may be an atelocollagen having far less antigenicity which is obtained by removing the telopeptide region by treating collagen with an enzyme (e.g. pepsin) in order to make safer. Gelatin is a protein derived from collagen. Gelatin is a high molecular weight amphoteric electrolyte which has less antigenicity and properties of convertible between sol and gel forms and is cheep in cost, and hence, it has already been confirmed as a safe substance for medical use. These are used alone or in combination of two or more thereof.

The medicaments and carriers used in the present invention are preferably purified products, but commercially available products may be used as they stand. The 215730 commercially available medicaments and carriers contain usually some appropriate additives such as stabilizers and buffering agents to some extent. For instance, an aqueous collagen solution contains usually a buffer of inorganic or organic salts, such as a phosphate buffer, citrate buffer or acetate buffer. Commercially available peptides as mentioned above contain usually sodium chloride, albumin, and a buffer of Inorganic or organic salts as mentioned above. These products may be used as they stand, but in view of release-sustaining properties, it is preferable to remove such additives or other components.

The present invention is characteristic in that the preparation can be prepared neither necessity of use of any specific binding agent nor necessity of heating during the step of preparation (being able to be prepared at room temperature or lower temperature), and owing to these characteristics, the sustained-release preparation of the present invention is particularly suitable for the above-mentioned peptides which are unstable to heat.

The sustained-release preparation of the present invention can be prepared in the following manner.

The active ingredient is added to a solution containing the carrier (usually an aqueous solution) and then the mixture is dried by conventional methods, for example, by allowing to stand or by lyophilization or spray-drying. The mixture may optionally be concentrated at a low 215730 temperature before drying, for example, by allowing to stand the solution at room temperature. In the above steps, the mixing step and drying step are usually carried out at room temperature or lower temperature and optionally under cooling. For instance, the mixing step is usually carried out at about 58C to 30°C; the drying by lyophllization is usually carried out at ~50°C to 0°C; and the drying by allowing to stand or by spray-drying is usually carried out at room temperature or lower (e.g. about 15°C to 30°C). Besides, the spray-drying is usually carried out by controlling the temperature of the solution and vessel at room temperature or lower, by which the temperature of the active ingredient can be kept at room temperature or lower and hence no damage Is given to the active ingredient even though it is unstable to heat.

The preparation of the present invention consists essentially of an active ingredient and the carrier. When other materials than the carrier are contained in the preparation, the release of the active ingredient is occasionally prompted thereby, and hence, In view of the sustained-release, it is preferable not to contain such other materials. Thus, it is preferable to make the content of other materials than the carrier as small as possible. However, from the practical viewpoint, the preparation may contain other components origined from the commercially available medicaments and carriers unless they affect 215730 substantially on the release-sustaining properties.

Likewise, the preparation of the invention may be incorporated by pharmaceutically acceptable conventional stabilizers, preservatives, and local anesthetic agents unless they affect substantially on the release-sustaining properties.

The dried product obtained above may optionally be processed to form the desired shape or form suitable for application. The preparation thus obtained is pulverized into powders under cooling with dry ice or liquid nitrogen so that the preparation is kept at about -10°C to about -100°C, or any other conventional pulverization methods at room temperature or lower. For instance, the dried product is pulverized into particles suitable for injection with a pulverizing machine, and the pulverized product is suspended in a viscous medium for injection to give a sustained-release suspension for injection. The pulverized product may also be used in the form of a kit with a viscous medium of injection, which are mixed when used. The viscous medium of injection includes, for example, sesame oil, peanut oil, cotton seed oil, medium chain triglycerides (MCT), olive oil, corn oil, castor oil, silicone oil, polyethylene glycol (PEG), propylene glycol (PG), iodine addition products of the ethyl esters of the fatty acids obtained from poppy seed oil, and the like.

Alternatively, the pulverized product may also be 21573 0 formed into a shaped product by compressing a fixed amount of the pulverized product in a mold. Moreover, the mixture of the active ingredient and the carrier solution may previously be entered into a mold, and then, the mixture is concentrated or allowed to dry or lyophilized and finally compressed to form a solid shaped product. A solid shaped product may also be prepared by injection molding. The solid shaped product may be in any shape such as spherical, cylindrical, needle-like, bar-like, and button-like shapes, so that the preparation is suitable for applying to the desired lesional region.

The sustained-release preparation of the present invention can be administered by subcutaneous injection or by insertion or implantation into the internal organs or body cabity.

The preparation of the present invention can be applied to human in order to promote growth by releasing the active ingredient for a long period of time and also applied to other animals such as cattle, sheep, pig, rabbit, hen and cock, and the like in order to promote the growth of the animals or to promote lactation (» milking). The effective dose of the active ingredient may somewhat vary depending on the kinds, body weight or age of the animals including human and administration route, but is in the range which is usually known for each peptide. Thus, the sustained-release preparation of the present invention contains the active 215/Jw ingredient in an amount in which the active ingredient is usually used. For example, GH is usually contained in an amount of 10"1 IU to 10^ iu, preferably 1 IU to 102 IU per dosage unit; GRF is usually contained in an amount of 10"1 mg to 10 g, preferably 1 rag to 1 g per dosage unit; SM is usually contained in an amount of 10~1 mg to 10 g, preferably 1 mg to 1 g per dosage unit; and calcitonin is usually contained in an amount of 10 IU to 1014 IU, preferably 102 IU to 10^ iu per dosage unit.

The present invention is illustrated by the following Examples and Experiment but should not be construed to be limited thereto.

Example 1 Gelatin (10 g) is dissolved in distilled water (100 ml). To the solution (5 ml) is added hGRF(1-44)NH2 (i.e. human GRF consisting of M amino acids) (20 mg), and the mixture is lyophilized. The lyophilized product is pulverized at a lower temperature using liquid nitrogen to obtain a powder of GRF - gelatin composite. The powdery composite (100 mg) is suspended in sesame oil (5 ml) to give a sustained-release oily suspension.

Example 2 IGF-I (1 mg) is dissolved in a phosphate buffer containing 2 % atelocollagen (2 ml), and the solution is lyophilized. The composite thus obtained is pulvelized at a low temperature using liquid nitrogen and then compressed in 2 1 57 j a mold to give a cylindrical shaped sustained-release preparation.

Example 3 B-HGH (a human growth hormone prepared by a genetic recombination technique) (100 IU in 0.9 w/v % physiological saline solution) Is dissolved in 10 % aqueous gelatin solution (3 ml). The mixture Is lyophilized. The lyophilized composite is pulvelized at a low temperature using liquid nitrogen and compressed in a mold to give a needle-like shaped, sustained-release preparation.

Example hGRF(1-29)NH2 (I.e. human GRF consisting of 29 amino acids) (100 mg) Is dissolved in distilled water (3 ml), and powdery collagen (1 g) is added thereto and swollen and then dissolved by regulating to pH 3.5. The gel-like composite thus prepared i3 defoamed and subjected to extrusion molding and then dried to give a sustained-release preparation in the form of a pellet.

Example 5 IGF-I (1 mg) is dissolved in a phosphate buffer containing 2 % atelocollagen (2 ml), and the solution is lyophilized. The composite thus obtained is pulverized at a low temperature using liquid nitrogen and then suspended in polyethylene glycol (3 ml) to give a sustained-release oily suspension.

I fin i !■ i in hi i<ma "" m 11 215730 • • Example 6 B-HGH (biosynthetic human growth hormone containing glycine 800 mg) (100 IU) is dissolved in 10 % aqueous gelatin solution (3 ml) and the solution is lyophilized. The composite thus obtained is pulverized at a low temperature using liquid nitrogen and then suspended in sesame oil (10 ml) to give a sustained-release oily suspension.

Experiment By using the sustained-release preparation as prepared in Example 4, the release rate of the active ingredient was tested a3 follows.

The preparation was added to a physiological saline solution, and the amount of hGRF(1-29)NH2 released therefrom was measured by a rotarory basket method with a basket stirring element as defined In U.S. Pharmacopeia.

The sum up release rate is shown in the accompanying Fig. 1, wherein the coordinate axis means the rate of releasing (J) and the abscissae axis means the time (hour) for releasing.

Claims (10)

21 573 - 12 - WHAT /AVE CLAIM 19)

1. A sustained-release preparation which comprises an effective amount of a peptide having a growth promoting activity or an activiy relating to bony metabolism in admixture with a carrier composed of one or more proteins selected from collagen, gelatin, albumin and a mixture thereof.

2. The preparation according to claim 1, wherein the preparation consists essentially of the peptide and the carrier.

3. The preparation according to claim 1 or 2, wherein the peptide having a growth promoting activity is a member selected from the group consisting of growth hormone (GH), growth hormone releasing factor (GRF) and somatomedin (SM).

4. The preparation according to claim 1 or 2, wherein the peptide having an activity relating to bony metabolism is calcitonin.

5. The preparation according to claim 1, 2, 3, or 4 which is in the form of an Injectable suspension which is prepared by suspending a pulverized product of the peptide carried on the carrier in a viscous medium for injection.

6. The preparation according to claim 1, 2, 3, or 4 which is in the form of a solid shaped product selected from spherical, cylindrical, needle-like, bar-like and button-like shapes. ■ 1 ^ t __ u__.J » 2157}

7. The preparation according to any one of claims 1, 2, 3i 5 and 6, wherein the carrier is a member selected from the group consisting of collagen, gelatin and a mixture of collagen and gelatin.

8. A method for the preparation of a sustained-release preparation, which comprises mixing a peptide having a growth promoting activity or an activity relating to bony metabolism and a carrier composed of one or more proteins selected from collagen, gelatin, albumin and a mixture thereof in the form of a solution, and concentrating or drying the mixture.

9. A preparation according to claim 1 substantially as herein described.

10. A method according to claim 8 substantially as herein described. SUMITOMO PHARMACEUTICALS COMPANY, LIMITED By His/ fhuir Attorneys, >X