FORM 2
THE PATENTS ACT 1970
(39 of 1970)
AND
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rulel3)
1. TITLE OF THE INVENTION:
"SIMPLE AND STABLE AQUEOUS INJECTABLE SUSPENSION FORM OF BETAMETHASONE SODIUM PHOSPHATE AND BETAMETHASONE
DIPROPIONATE"
2. APPLICANT:
(a) NAME: NEON LABORATORIES LTD.
(b) NATIONALITY: Indian Company incorporated under the
Companies Act, 1956
(c) ADDRESS: 140, Damji Shamji Industrial Complex, Mahakali Caves
Road, Andheri (East), Mumbai - 400093, Maharashtra, India.
3.PREAMBLE TO THE DESCRIPTION:
The following specification describes the nature of this invention and the manner in which it is to be performed:

TECHNICAL FIELD OF INVENTION:
The present invention relates to an aqueous injectable suspension comprising Betamethasone Sodium Phosphate and Betamethasone Dipropionate in easily re-dispersible form.
BACKGROUND AND PRIOR ART:
Betamethasone Dipropionate is a choice of drugs in the treatment of rheumatoid arthritis as compared to other corticosteroids. But it's difficult to develop in injectable formulation due to its aqueous insolubility. So there is difficulty in preparing injectable formulation or suspension form. Further, these suspension formulations, administered intramuscularly and thus produces more pain at the site of injection for longer duration; therefore the use of Betamethasone sodium phosphate is introduced to overcome above problems.
Betafos® is a sterile aqueous suspension contains a combination of soluble and very slightly soluble Betamethasone esters such as a combination of Betamethasone Sodium Phosphate and Betamethasone Dipropionate. The combination of Betamethasone Sodium Phosphate and Betamethasone Dipropionate together provide potent rapid and prolonged anti-inflammatory, anti-rheumatic and anti-allergic effects upon administration. Rapid therapeutic activity is achieved by the soluble ester Betamethasone Sodium Phosphate which is quickly absorbed after injection and sustained activity is provided by Betamethasone Dipropionate which is only slightly soluble and slowly absorbed thereby controlling symptoms over a prolonged period of time.
Thus this combination provides longer half-life and higher potency (20 times) compared to Cortisol (hydrocortisone). Further, this combination has no significant sodium or water retaining effect and hence has an edge over hydrocortisone.
Further, there is another product in the market under the trade name 'DIPROFOS' Suspension, which is a sterile aqueous injectable suspension of betamethasone dipropionate and betamethasone sodium phosphate by Scherring Plough. Each ml of DIPROFOS suspension contains betamethasone dipropionate equivalent to 5 mg

betamethasone and betamethasone sodium phosphate equivalent to 2 mg betamethasone in a sterile buffered and preserved vehicle.. Aqueous suspensions often have problems such as difficulty in redispersion due to aggregation of drug particles, formation of macro crystals from suspended particles or formation of secondary particles from deposited particles and also some types of suspended particles adhere to or get adsorbed by the walls of a container and hence inaccuracy of the dosage form. On the other hand, increasing of the size of particles in the suspension would cause problems such as foreign body sensation upon application or clogging of a container nozzle or a syringe needle.
Therefore, there is a need in the art to provide a stable injectable suspension form comprising betamethasone dipropionate and betamethasone sodium phosphate, which is easily re-dispersible to achieve required constitution. Thus the present invention aims to overcome one or more problems such as redispersibility associated with the available injectable formulations.
The object of the present invention is to prevent the problems of aqueous suspensions which often have problems such as difficulty in redispersion due to aggregation of drug particles, formation of macro crystals from suspended particles or formation of secondary particles from deposited particles and also some types of suspended particles adhere to or get adsorbed by the walls of a container. On the other hand, increasing of the size of particles in the suspension would cause problems such as foreign body sensation upon application or clogging of a container nozzle or a syringe needle.
Therefore, the objective of the invention is to provide simple and stable Injectable suspension form of Betamethasone Sodium Phosphate and Betamethasone Dipropionate with good dispersiblity.
SUMMARY OF THE INVENTION;
In accordance with the above, the present invention provides a composition that contains ionic macromolecules with the following advantages:
• Minimum chances of development of particle size, so less chances of foreign body sensation upon application or clogging of a container nozzle or a syringe needle.

• Improved retention of drug at injection site, as it contains optimum concentration
of macromolecules.
• Benzalkonium chloride free: instead of Benzaikonium chloride used optimum
concentration of Benzyl alcohol.
In an aspect, the present invention provides an aqueous injectable suspension comprising Betamethasone Sodium Phosphate and Betamethasone Dipropionate with good re-dispensability, syringibility which will have minimum pain on the site of injection.
According to the present invention, the combination of above steroidal anti-inflammatory agents produces synergistic anti rheumatic effect as well as reduces the local inflammation and pain. The injectable suspension of the invention is devoid of side effects such as allergic reaction including redness, large swollen area, bruising at the injectation site, rash, fever and cellulites thereof.
In another aspect, the present invention provides highly stable steroidal anti-inflammatory aqueous suspension with longer duration of action together with extended time storage/ shelf life.
Another aspect of the present invention provides injectable formulation which consists of small sized particle causing less pain as compared to other marketed Injectable formulations.
In accordance with the above, the invention discloses an aqueous injectable suspension of Betamethasone Sodium Phosphate and Betamethasone Dipropionate in easily re-dispersible form having different physicochemical properties for systemic antirhumatic action along with local antihistaminic and anti-inflammatory action, comprising;
a) Betamethasone dipropionate equivalent to 5 mg Betamethasone
b) Betamethasone sodium phosphate equivalent to 2 mg Betamethasone
c) Polyvinylpyrrolidone PF (Kollidon K 12) and other pharmaceutical excipients, wherein, said suspension is free of Benzalkonium chloride.

The pharmaceutical excipients according to the invention are selected from preservatives, suspending agents, dispersing agent, cosolvent, wetting agents, tonicity modifier, buffering agent, chelating agents and pH adjusters.
The preservatives are selected from the group consisting of Sodium Methyl Paraben, Sodium Propyl Paraben and Benzyl alcohol. The Sodium methyl paraben used in concentration of 0.08% w/v. sodium propyl paraben used in concentration of 0.011% w/v and Benzyl alcohol used in concentration of 0.9% v/v.
The suspending agent is selected from Sodium carboxymethyl cellulose and dispersing agent is selected as Polyvinylpyrrolidone PF (Kollidon K 12). The sodium carboxymethyl cellulose is used in the range between 0.2% w/v to 0.6% w/v more preferably used in an amount of 0.4 % w/v. The Polyvinylpyrrolidone PF (Kollidon K 12) is used in the range between 0.02 % w/v to 0.2% w/v, more preferably in an amount of 0.05% w/v.
The wetting agent is selected from Polysorbate 80 and cosolvent selected as Polyethylene glycol 400. Polysorbate 80 is used in the range of 0.15 %w/v to 0.35 % w/v, more preferably in 0.25 % w/v; and Polyethylene glycol 400 is used in the range of 0.1 % w/v to 0.2 % w /v, more preferably in 0.15 % w/v.
The tonicity modifier is sodium chloride used in concentration 0.5 % w/v . The buffering agent is Disodium hydrogen phosphate used in concentration of 0.011% w/v.
The chelating agent is Disodium EDTA used in concentration of 0.019% w/v.
In another preferred embodiment, the invention discloses process for preparation of aqueous injectable suspension encompasses Betamethasone Sodium Phosphate and Betamethasone Dipropionate in easily re-dtspersible form comprising
a) Soaking the dissolved suspending agent, Sodium carboxymethyl cellulose in water for injection followed by filtering the above solution through muslin cloth
b) Preparing Surfactant Solution by dissolving and mixing homogenously Polysorbate 80 and polyethylene glycol 400; and autoclaving both solutions;

c) Preparing Betamethasone Dipropionate Suspension by dispersing micronized and Sterile Betamethasone Dipropionate in solution of step (b) under stirring followed by the addition of solution of step (a) with continued the stirring to obtain part I solution;
d) Preparing Betamethasone Sodium Phosphate Solution by dissolving Betamethasone Sodium Phosphate Sodium Methyl Paraben, Sodium Chloride,-Disodium hydrogen phosphate, Disodium EDTA , Sodium Propyl Paraben and benzyl alcohol in water for injection with vigorous stirring till to get clear solution; (part II) followed by aseptic filtration through 0.2^i sterile filtration unit and
e) Aseptically adding Part II solution slowly in Part I, under stirring followed by addition of sterilized Polyvinylpyrrolidone PF (Kollidon K 12) solution in water for injection with continuous stirring at optimum speed and made up the volume with water for injection.
DETAILED DESCRIPTION OF THE INVENTION:
In accordance with the above, the present invention provides an improved aqueous suspension comprising combination of Betamethasone Sodium Phosphate and Betamethasone Dipropionate by overcoming all the above product non compliances.
According to the preferred embodiment, the invention comprises betamethasone dipropionate equivalent to 5 mg betamethasone and betamethasone sodium phosphate equivalent to 2 mg betamethasone together with Polyvinylpyrrolidone PF (Kollidon K 12). Addition of Polyvinylpyrrolidone PF (Kollidon K 12) of injection grade will act as Solubilizer ; delays crystallization and also acts as dispersing agent, this is particularly important in suspension to improve the redispersibility of hardly soluble drugs in an aqueous suspension. The aqueous suspension of the instant invention is free of Benzalkonium chloride as the use of the same cause irritation, redness, large swollen areas, bruising, rash, fever etc. The aqueous suspension of the instant invention further comprises Preservatives selected from Sodium Methyl Paraben, Sodium Propyl Paraben, Benzyl alcohol; Suspending agent such as Sodium carboxymethyl cellulose, Polyvinylpyrrolidone PF (Kollidon K 12); Wetting agent such as Polysorbate 80;

cosolvent such as Polyethylene glycol 400 , tonicity modifier such as Sodium chloride; Buffering agent selected from Disodium hydrogen phosphate; and Chelating agent such as Disodium EDTA.
In another preferred embodiment, the invention provides a manufacturing process, which is simple and easily scalable.
Accordingly, at first stage, Sodium Carboxymethyl Cellulose (CMC) Solution is prepared by dissolving the same in water for injection under stirring at about 80°C and soaked for a minimum of 4 hours. The solution thus obtained is filtered through muslin cloth. In a separate vessel Polysorbate 80 and Polyethylene glycol 400 are added and mixed homogenously. Both the solution vessels are covered with lid and autoclaved at 121°C for 30 minute. Betamethasone Dipropionate Suspension is prepared under aseptic conditions by adding the same to surfactant solution under stirring to obtain a homogenous suspension. This suspension is added under vigorous stirring at about 4000 to 5000 rpm speed to the sodium carboxymethyl cellulose solution and continued stirring for 2 hours.
At second stage, Betamethasone Sodium Phosphate Solution is prepared in water for injection under stirring by adding and dissolving Betamethasone sodium phosphate, Sodium Methyl Paraben, Sodium Propyl Paraben, Sodium Chloride, Disodium EDTA to achieve clear solution. To this solution, benzyl alcohol is slowly added under stirring to get clear solution. The solution thus obtained is sterilized by aseptic filtration through 0.2u. sterile filtration unit with Nylon 6, 6 membrane filter and aseptically transfered to sterile area(Class 100 area).
At a third stage, Polyvinylpyrrolidone PF (Kollidon K 12)solution is prepared by taking the same in water for injection under stirring followed by sterilizing the solution by filtration through 0.2 u. Nylon 6, 6 membrane filter.
At fourth stage, two solutions are added aseptically to stage one solution under stirring with Over Headed Stirrer, followed by the aseptical addition of Polyvinylpyrrolidone PF (Kollidon K 12) Solution under continued stirring for 2 hours at stirring speed of about 4000 RPM. The pH is adjusted to 7.0 ± 0.2 using IN Hydrochloric acid.

The formulation prepared as above are studied for its shelf life and found to be stable under accelerated conditions. Accordingly, in another embodiment, the invention provides the stability data of the above formulation as below
In another embodiment, the invention provides a comparative study of the instant invention with marketed formulation. The study indicates that the instant product is superior by having good dispersibility, redispersibility and remains in suspended form for longer period of time than the marketed sample. The details are provided in the below table 1.
Table. 1 Comparative study of Neon formulation and Market sample formulation

Sr.
No. Parameters Neon Formulation(BETAPIONATE) Market Sample (DIPROSPAN) By Schering Plough
1 Average Particle size 10 µm 90µm
2 Average Settling time 20 Min. 5 Min.
3 Redispersion study Good dispersibilty and remain Dispersible but settles
(By gentle shaking) suspended for longer than fast than Neon
market sample / Formulation due to comparatively larger particle size
From the above it is clear that the instant invention is found to be superior in various aspects such as redispersiblilty. Addition of Polyvinylpyrrolidone PF (Kollidon K 12) of injection grade will act as solubilizer and its function in delaying crystallization and also as dispersing agent, particularly an important excipient in suspension formulation of the instant invention to improve the redispersibility of hardly soluble drugs in an aqueous suspension. Thus the instant invention avoids adherence of the suspended contents to the wall of container, since it contains Polyvinylpyrrolidone PF (Kollidon K 12). This invention also alleviate the chances of development of particle size, so less chances of foreign body sensation upon application or clogging of a container nozzle or a syringe needle. The invention also achieves improved retention of drug at injection site, as it contains optimum concentration of macromolecules. The instant invention further

advantageously avoided the use of Benzalkonium chloride and instead of Benzalkonium chloride used optimum concentration of Benzyl alcohol and thus avoided the side effects which comes with the use of benzalkonium chloride such as irritation, redness, large swollen area, bruising, rash, fever etc.
Also, the instant invention is able to achieve prompt therapeutic activity by the use of soluble ester, Betamethasone sodium phosphate, and insoluble Betamethasone Dipropionate thereby controlling symptoms over a prolonged period by providing the desired therapeutic levels in the body.
The following examples of different formulation are described in Table-2 .The test results for the above described suspension for injection is found satisfactory out of which optimized batches are subjected to stability studies as per ICH guidelines and found that all the parameters like assay, particles size and Redispersibilty within specified limits.

Table: 2 Examples of Betamethasone suspension

SR. NO. INGERDIENTS EXAMPLE 1 EXAMPLE 2 OPTIMIZED BATCH EXAMPLE 4 EXAMPLE 5 RATIONALE
1. Betamethasone Dipropionate equivalent to Betamethasone 0.5% w/v 0.5% w/v 0.5% w/v 0.5% w/v 0.5% w/v Active ingredient
2. Betamethasone sodium phosphate equivalent to Betamethasone 0.2% w/v 0.2% w/v 0.2% w/v 0.2% w/v 0.2% w/v Active ingredient
3. Sodium carboxymethyl cellulose 0.2% w/v 0.3% w/v 0.4% w/v 0.5% w/v 0.6% w/v Suspending agent -
4. Polysorbate 80 0.15% w/v 0.2%w/v 0.25% w/v 0.3% w/v 0.35% w/v Wetting agent
5. Polyethylene glycol 400 0.1% w/v 0.125% w/v 0.15% w/v 0.175% w/v 0.2 % w/v Cosolvent
6. Disodium EDTA 0.019% w/v 0.019% w/v 0.019% w/v 0.019% w/v 0.019% w/v Chelating agent
7. Sodium chloride 0.5% w/v 0.5% w/v 0.5% w/v 0.5% w/v 0.5% w/v Tonicity modifier
8. Disodium hydrogen phosphate 0.011% w/v 0.011% w/v 0.011% w/v 0.011% w/v 0.011% w/v Buffering agent
9. KolIidonK12 (Povidone K-12) 0.0% w/v 0.025% w/v 0.05% w/v 0.075 % w/v 0.1% w/v Solubiiiser, Dispersing agent
10. Sodium Methyl Paraben 0.08% w/v 0.08% w/v 0.08% w/v 0.08% w/v 0.08% w/v Preservative
11. Sodium Propyl Paraben 0.011% w/v 0.011% w/v 0.011% w/v 0.011% w/v 0.011% w/v Preservative
12. Benzyl alcohol 0.9% v/v 0.9% v/v 0.9% v/v 0.9% v/v 0.9% v/v Preservative
13. Hydrochloric acid q.s. q.s. q.s. q.s. q.s. pH adjustifier
14. Water for injection q.s. q.s. q.s. q.s. q.s.„ Vehicle

ITY REPORT OF FIRST STABILTY BATCH
Betamethasone Dipropionate & Betamethasone Sodium Phosphate Suspension for Injection 5mg & 2 mg/ml-lml Primary packing: 2 ml Flint Ampoule with Yellow band snap off

Sr. No. Parameters STD Limit Withdrawal Period MARKET

Initial 11 VI 2M 3M 6M SAMPLE

RT 40° C RT 40° C RT 40° C RT 40° C (analysed on January 2011)
D1PROSPAN by Scheri rig-plough
1. Description * Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
2. Identification ** Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
3. pH Between 6.5 to 7.5 6.68 6.67 6.67 6.68 6.71 6.71 6.73 6.66 6.60 6.60
4. Particulate Matter To Comply Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
5. Particle Size 90%NMT 15 urn 90% Less than 10 um 90% Less than 10 pm 90% Less than 10 um 90% Less than 10 urn 90% Less than 12 um 90% Less than 10 um 90% Less than 12 pm 90% Less than 12 pm 90% Less than 12 pm 10% Less than 15um
6. Bacterial Endotoxins NMT 350 EU/ml Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
7. Sterility To Sterile Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
8. Pyrogen To Comply Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
9. Toxicity To Comply Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
10. Assay (By HPLC) Betamethasone Dipropionate equivalent to Betamethasone
Betamethasone Sodium Phosphate equivalent to Betamethasone N.L.T. 90.0% N.M.T.110.0%
N.L.T. 90.0% N.M.T.110.0% 100.00%
104.50% 105.15% 102.13% 104.75% 101.66% 101.02% 102.92% 102.94% 99.76% 100.91% 101.83% 101.85% 99.66% 98.30% 103.10% 101.08% 97.02% 101.02% 102.92%
* A white colored suspension. ** Solution free from foreign particulate matter visible to unaided eyes. Market Sample:MFGR: Schering - plough, B. No.: 9BBKA9A01, MFG Date: May.'2008, Exp Date: May'2011

STABILITY REPORT OF SECOND STABILTY BATCH Primary packing: 2 ml Flint Ampoule with Yellow band snap off

Sr.
No. Parameters STD Limit Withdrawal Period MARKET

Initial IM 2M 3M 6M SAMPLE

RT 40° C RT 40° C RT 40° C RT 40° C (analysed on January 2011)
DIPRSPAN by
Schering-plough
1. Description To Comply Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
2. Identification To Comply Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
3. pH Between 6.5 to
7.5 6.68 6.73 6.72 6.70 6.71 6.68 6.70 6.64 6.69 6.60
4. Particulate Matter To Comply Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
5. Particle Size 90%NMT 15 urn 90% Less 90% Less 90% Less 90% Less 90% Less 90% Less 90% Less 90% Less 90% Less 10% Less than
than 10 fim than 10u,m than 10 jam than 10 um than 12 um than 10 um than 12 pm than 12 um than 12 um 15um
6. Bacterial Endotoxins NMT 350 EU/ml Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
7. Sterility To Sterile Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
8. Pyrogen To Comply Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
9. Toxicity To Comply Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
10. Assay (By HPLC) Betamethasone Dipropionate equivalent to Betamethasone N.L.T. 90.0% N.M.T.I 10.0% 100.46% 103.00% 98.17% 100.58% 100.55% 100.42% 100.19% 99.75% 99.35% 101.7%
Betamethasone Sodium Phosphate N.L.T. 90.0% N.M.T.110.0% 103.70% 101.51% 100.01% 104.79% 98.39% 103.48% 98.13% 103.40% 97.39% 104.79%
equivalent to Betamethasone
* A white colored suspension. ** Solution free from foreign particulate matter visible to unaided eyes. Market Sample:MFGR: Schering-plough, B. No.: 9BBKA9A01, MFG Date: May.'2008, Exp Date: May'201f

STABILITY REPORT OF THIRD STABILTY BATCH Primary packing: 2 ml Flint Ampoule with Yellow band snap off

Sr. No. Parameters STD Limit Withdrawal Period MARKET

Initial 1M 2M 3M 6M SAMPLE

RT 40° C RT 40° C RT 40° C RT 40° C (analysed on Jan 2011)
DIPROSPAN by Schering-plough
1. Description To Comply Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
2. Identification To Comply Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
3. pH Between 6.5 to 7.5 6.68 6.71 6.65 6.68 6.69 6.69 6.72 6.66 6.60 6.60
4. Particulate Matter To Comply Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
5. Particle Size 90%NMT 15 urn 90% Less than 10 um 90% Less than 10 urn 90% Less than 10 u.m 90% Less than 10 urn 90% Less than 12 p.m 90% Less than 10 um 90% Less than 12 urn 90% Less than 12 um 90% Less than 12 um 10% Less than 15um
6. Bacterial Endotoxins NMT350EU/ml Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
7. Sterility To Sterile Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
8. Pyrogen To Comply Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
9. Toxicity To Comply Complies Complies Complies Complies Complies Complies Complies Complies Complies Complies
10. Assay (By HPLC) Betamethasone Di propionate equivalent to Betamethasone
Betamethasone Sodium Phosphate equivalent to Betamethasone N.L.T. 90.0% N.M.T. 110.0%
N.L.T. 90.0% N.M.T.I 10.0% 100.92%
104.60% 101.23% 101.37% 101.70% 101.39% 100.58% 101.46% 100.36% 98.08% 100.08% 100.96% 100.19% 98.10% 102.87% 97.27% 101.65% 96..65% 102.36% 98.08%
* A white colored suspension. ** Solution free from foreign particulate matter visible to unaided eyes. Market Sample:MFGR: Schering - plough, B. No.: 9BBKA9A01, MFG Date: May.'2008, Exp Date: May'2011

Conclusion: The Betamethasone suspension developed with rationale method showed successful compliant redispesibilty at long term 25°C and Accerated condition 40°C throughout 6 months and hence the stable specification without significant difference in partical size and suspension quality.

We claim,
1. An aqueous injectable suspension comprising Betamethasone Sodium Phosphate
and Betamethasone Dipropionate in easily re-dispersible form having different
physicochemical properties for systemic antirhumatic action along with local
antihistaminic and anti-inflammatory action, comprising;
a) Betamethasone Dipropionate equivalent to 5 mg betamethasone
b) Betamethasone sodium phosphate equivalent to 2 mg betamethasone
c) Polyvinylpyrrolidone PF (Kollidon K 12) and other pharmaceutical excipients,

2. The aqueous injectable suspension according to claim 1, wherein, said suspension is free of Benzalkonium chloride.
3. The aqueous injectable suspension according to claim 1, wherein, pharmaceutical excipients are selected from preservatives, suspending agents, dispersing agent, wetting agents, tonicity modifier, buffering agent, chelating agents, co-solvent and pH adjusters.
4. The aqueous injectable suspension according to claim 1, wherein, the preservatives are selected from the group consisting of Sodium Methyl Paraben, Sodium Propyl Paraben and Benzyl alcohol.
5. The aqueous injectable suspension according to claim 4, wherein, the Sodium methyl paraben used in concentration of 0.08% w/v, sodium propyl paraben used in concentration of 0.011% w/v and Benzyl alcohol used in concentration of 0.9%
v/v.
6. The aqueous injectable suspension according to claim 1, wherein, the suspending agent is selected from Sodium carboxymethyl cellulose and dispersing agent as Polyvinylpyrrolidone PF (Kollidon K 12).
7. The aqueous injectable suspension according to claim 6, wherein, the sodium carboxymethyl cellulose is used in the range between 0.2% w/v to 0.6% w/v more preferably used in 0.4 % w/v.

8. The aqueous injectable suspension according to claim 1, wherein, the wetting agent is selected as Polysorbate 80 and co solvent as Polyethylene glycol 400.
9. The aqueous injectable suspension according to claim 8, wherein, the Polysorbate 80 is used in the range between 0.15 %w/v to 0.35 % w/v, more preferably in 0.25 % w/v.
10. The aqueous injectable suspension according to claim 8, wherein, the Polyethylene glycol 400 is used in the range between 0.1 % w/v to 0.2 % w /v, more preferably in 0.15 % w/v.
11. The aqueous injectable suspension according to claim 1, wherein, the tonicity modifier is sodium chloride used in concentration 0.5 % w/v .
12. The aqueous injectable suspension according to claim 1, wherein the buffering agent is Disodium hydrogen phosphate used in concentration 0.011% w/v.
13. The aqueous injectable suspension according to claim 1, wherein the chelating agent is Disodium EDTA used in concentration 0.019% w/v.
14. The aqueous injectable suspension according to claim 1, wherein the Polyvinylpyrrolidone PF (Kollidon K 12) used in the range between 0.02 % w/v to 0.2% w/v, more preferably in 0.05% w/v.

15. A process for preparation of aqueous injectable suspension comprising Betamethasone Sodium Phosphate and Betamethasone Dipropionate in easily re-dispersible form comprising
a. Soaking the dissolved suspending agent, Sodium carboxymethyl cellulose in
water for injection followed by filtering the above solution through muslin
cloth.
b. Preparing Surfactant Solution by dissolving and mixing homogenously
Polysorbate 80, polyethylene glycol 400 autoclaving both solutions.
c. Preparing Betamethasone Dipropionate Suspension by dispersing micronized
and Sterile Betamethasone Dipropionate in solution of step (b) under stirring
followed by the addition of solution of step (a) with continued the stirring to
obtain part I solution.
d. Preparing Betamethasone Sodium Phosphate Solution by dissolving
Betamethasone Sodium Phosphate, Sodium Methyl Paraben, Sodium
Chloride, Disodium hydrogen phosphate, Disodium EDTA , Sodium Propyl
Paraben and benzyl alcohol -in water for injection with vigorous stirring till to
get clear solution (part II) followed by aseptic filtration through 0.2^ sterile
filter.
e. Aseptically adding Part II solution slowly in Part J, under stirring followed by
addition of sterilized Polyvinylpyrrolidone PF (Kollidon K 12) solution in
water for injection with continuous stirring at optimum speed and made up the
volume with water for injection.