FORM 2
THE PATENT ACT 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rule13)
1. TITLE OF THE INVENTION:
STABILIZED PHARMACEUTICAL COMPOSITIONS OF INTERFERON

2. APPLICANT (S)
(a) NAME: WOCKHARDT LTD.
(b) NATIONALITY: INDIAN
(c) ADDRESS: WOCKHARDT LIMITED, D-4, MIDC, CHIKALTHANA,
AURANGABAD (M.S.) INDIA.
3. PREAMBLE TO THE DESCRIPTION
The invention provides a stable pharmaceutical composition comprising interferon b and an effective amount of trehalose.
The following specification particularly describes the invention and the manner in which it is to be performed.


4. Description
The invention provides a stable pharmaceutical composition comprising interferon p and an effective amount of trehalose.
Interferons (alpha, beta and gamma) are glycoproteins produces in the cells of vertebrates. Interferon b-1a is a 166 amino acid glycoprotein with a predicted molecular weight of approximately 22,500 daltons. Formulated Interferon b-1a is available in the market under the trade name of Avonex® and Rebif®. The amino acid sequence of interferon b-1a used in Avonex® and Rebif® is identical to that of natural human interferon b- 1a.
Interferon b-1a is indicated for the treatment of relapsing forms of multiple sclerosis to slow the accumulation of physical disability and decrease the frequency of clinical exacerbations.
Interferon- b is produced by mammalian cells (Chinese Hamster Ovary cells) into which the human interferon b gene has been introduced. Use of recombinant DNA technology allows the interferon to be produced on industrial scale in a highly purified form.
Proteins which are obtained in a highly purified form are susceptible to denaturation, degradation or aggregation even in normal atmospheric conditions. Physical as well as chemical instabilities results in loss of biological activity of the proteins. Thus it is desirable to produce a pharmaceutical composition which is stable and tends to inhibit or delay the degradation of active principle, thus ensuring the stability of formulation during life cycle of the product.
US Patent No. 6,852,314 discloses a liquid pharmaceutical formulation consisting of about 0.6 to 24 MlU/ml of interferon p, mannitol, and an acetate buffer at a pH between 3.0 and 4.0 and, optionally, albumin.


US Patent Application 20040265270 discloses a liquid pharmaceutical formulation consisting essentially of recombinant interferon- b, a citrate buffer and a stabilizing agent which is mannitol.
US Patent No. 4,675,184 a pharmaceutical composition for treating viral diseases containing interferon, glycerin, an organic acid buffer.
US Patent No. 5,004,605 discloses a stable pharmaceutical composition comprising a recombinant interferon-P protein dissolved in an inert carrier medium comprising as a stabilizer/solubilizer an effective amount of polyethylene glycol polymers.
US Patent No. 6,994,847 and US Patent Application No. 20060008447 discloses a composition comprising biologically active interferon- b and highly purified mannitol.
US Patent No. 6,923,956 discloses a liquid formulation comprising a glycosylated human interferon-p as an active ingredient, a buffer, and methionine.
U. S. Patent No. 5,460,811 discloses a composition comprising water and a nonglycosylated polypeptide having the amino acid sequence of a mature human fibroblast interferon.
US Patent Application No. 20030190307 discloses a liquid composition comprising an interferon and a stabilizing agent which is an amino acid selected from the group consisting of acidic amino acids, arginine and glycine.
The present inventors while working on the interferon-b have observed that the addition of trehalose results in stable pharmaceutical formulation. Trehalose helps in retaining native conformation of the active ingredient and thereby stabilizes the formulation.


One of the aspects of the invention provides a stable pharmaceutical composition comprising biologically active interferon-p and an effective amount of trehalose.
The composition of the present invention is free of saccharose and mannitol.
In one of the embodiments of the invention, the stable pharmaceutical composition comprising interferon-P and trehalose has a pH from about 3.0 to 7.0.
In another embodiment of the invention, the composition is a liquid in injectable or infusible form as solution, or lyophilized solid suitable for reconstitution.
In yet another embodiment of the invention, the pharmaceutical composition may further comprises of carriers, isotonic agent, buffer, surfactants or solubilizing agents, complexing agents, antioxidants, preservatives and vehicle.
The carriers useful in the invention include human serum albumin of natural origin or recombinant human serum albumin or other known in the art. The total amount of human serum albumin present in the formulation varies from 0.01 to 2 % w/v.
Isotonic agents such as sodium chloride, sodium phosphate or sodium sulphate or the like can be added to achieve the desired isotonicity.
Examples of suitable buffer include citrate buffer, acetate buffer, phosphate or succinate buffer and the like.
Non-limiting examples of solubilizing agents encompassed by the invention include non-ionic surfactants free of peroxides e.g. cholic acid, chenodeoxycholic acid, sodium taurocholate, cetrimide, polyoxyethylene sorbitan fatty acid esters such as polysorbate 80, polysorbate 40 and polysorbate 20 and the like.


Complexing agents useful in the invention include but are not limited to ethylenediaminetetraacetic acid or salt thereof.
Antioxidants and preservatives such as propyl gallate, butylated hydroxy toluene, butylated hydroxy anisole, benzalkonium chloride, chlorobutanol, methyl paraben, propyl paraben, phenylethyl alcohol, cysteine, cysteinate HCI, dithionite sodium, gentisic acid, gentisic acid ethanolamine, glutamate monosodium, cetrimides, and the like can be added to the formulation of the invention.
Vehicles suitable for formulating the invention include but are not limited to water for injection.
Example 1
Table 1: Liquid Composition of Interferon-B 1a

S.No. Ingredients mg/ml
1 Interferon b1a (rDNA ) 0.088
2 Albumin Human 6-10
3 Trehalose 24-34
4 Sodium acetate 0.6-1.0
5 Acetic acid glacial q.s. to pH
6 Water for injection q.s. to 1 ml
PH 3.7-4.3
Procedure: The above composition is prepared by simple mixing that involves the step of dissolving sodium acetate in water for injection followed by addition of human serum albumin and trehalose with gentle stirring. The pH of the solution obtained is adjusted to 3.7 to 4.3. The solution is then sterilized by filtering it through a 0.2 u syringe filter. Pre-sterilized Interferon-B 1a concentrate is finally added to the above sterile solution and final volume is adjusted with water for injection.


While the invention has been described in terms of its specific embodiments, certain modifications and equivalents will be apparent to those skilled in the art and are intended to be included within the scope of the invention.


WE CLAIM:
1. A stable pharmaceutical composition comprising biologically active interferon-P and an effective amount of trehalose.
2. The stable pharmaceutical composition of claim 1, wherein the composition has pH from 3.0 to 7.0.
3. The stable pharmaceutical composition of claim 1, wherein the composition is a liquid in injectable or infusible form such as solution, or lyophilized solid suitable for reconstitution.
4. The stable pharmaceutical composition of claim 1, further comprises of carriers, isotonic agent, buffer, surfactants or solubilizing agents, complexing agents antioxidants, preservatives and vehicle.
5. The stable pharmaceutical composition of claim 4, wherein the carriers comprises of human serum albumin of natural origin or recombinant human serum albumin or other known in the art.
6. The stable pharmaceutical composition of claim 4, wherein the isotonic agents comprises of one or more of sodium chloride, sodium phosphate or sodium sulphate and the like.
7. The stable pharmaceutical composition of claim 4, wherein the suitable buffers comprises of one or more of citrate buffer, acetate buffer, phosphate or succinate buffer.
8. The stable pharmaceutical composition of claim 4, wherein the suitable solubilizing agents is a non-ionic surfactants free of peroxides e.g. cholic acid, chenodeoxycholic acid, sodium taurocholate, cetrimide,


polyoxyethylene sorbitan fatty acid esters such as polysorbate 80, polysorbate 40 and polysorbate 20 and the like.
9. The stable pharmaceutical composition of claim 4, wherein the suitable complexing agents is ethylenediaminetetraacetic acid or salt thereof
10. The stable pharmaceutical composition of claim 4, wherein the suitable antioxidants and preservatives includes one or more of propyl gallate, butylated hydroxy toluene, butylated hydroxy anisole, benzalkonium chloride, chlorobutanol, methyl paraben, propyl paraben, phenylethyl alcohol, cysteine, cysteinate HCI, dithionite sodium, gentisic acid, gentisic acid ethanolamine, glutamate monosodium, cetrimides, and the like



Abstract
The invention provides a stable pharmaceutical composition comprising interferon and trehalose.