Technical Field:

The present invention relates to a stable oral solution of Spironolactone and method of preparing the same. Particularly, the present invention relates to a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients.

Background of the Invention:

Spironolactone is an aldosterone antagonist having utility as a potassium sparing diuretic. Spironolactone is used to diagnose or treat condition in which person has elevated level of aldosterone. Aldosterone is a hormone produced by the adrenal glands to help to regulate the salt and water balance in the body. Spironolactone is employed in the management of primary hyperaldosteronism and the treatment of congestive heart failure.

Spironolactone is white to off white powder with slightly bitter in taste. It is practically insoluble in water. Spironolactone is chemically known as 17- Hydroxy-7a-mercapto-3-oxo-17a-pregn-4-ene-21- carboxylic acid, g-lactone acetate. Spironolactone is having an empirical formula of C24H32O4S and a molecular weight of 416.6g/mol. Its chemical structure is as follows:

Currently, spironolactone is marketed as tablets in strengths of 25 mg, 50mg and 150 mg per packet under the trade name Aldactone® and as a suspension in strength of 25mg under the trade name of Carospir®which is potassium sparing diuretic. The solution dosage form of Spironolactone is not commercially available because its aqueous solubility is reported to be only 28 pg/ml.

Solid oral dosage forms such as tablets and capsules have the largest and most important role in the entire pharmaceutical formulations. However, there are many patients who have difficulties swallowing these dosage forms and oral liquid dosage forms are chosen by patients who are travelling or have little access to water or patients who are physically disabled or mentally retarded. Further, the fear of swallowing or choking on such solid dosage forms is still a concern in certain populations, especially paediatric and geriatric patients.

Hence, to overcome the aforementioned problems drugs are formulated as liquid dosage forms for oral administration, for example as solutions, suspensions, emulsions and syrups. Such dosage forms permit ease of administration and increases patient compliance. An additional advantage of liquid dosage forms is dose flexibility, which is particularly advantageous for infants, children and the elderly. A further advantage is that a drug administered in a liquid dosage form is often more rapidly absorbed after oral administration than if formulated in tablets or capsules. Various attempts have been made to develop liquid dosage form of Spironolactone.

Y. Pramar, V. Das Gupta and C. Bethea, Development of a stable oral liquid dosage form of spironolactone, journal of Clinical Pharmacy and Therapeutics (1992) volume 17, page nos. 245-248 discloses oral liquid dosage form of spironolactone comprising of propylene glycol, polyethylene glycol, glycerine, and phosphate or citrate buffer.

Kaukonen et al. Water-soluble Beta Cyclodextrins in Paediatric oral solutions of Spironolactone. Preclinical Evaluation of Spironolactone bioavailability from solutions of Beta cyclodextrin derivatives in rats, Journal of Pharmacy and Pharmacology (1998) 50(6): page nos. 611-619 discloses an oral solution of spironolactone containing water-soluble derivatives of P-cyclodextrin (e.g., sulfobutyl ether P-cyclodextrin (SBE7) or dimethyl-P-cyclodextrin (DM-P-CyD)).

US4837211 disclose spironolactone dosage forms, either in the form of a solid powder composition which may be readily aqueously homogenized prior to ingestion, or else in the form of an aqueous spironolactone suspension. The composition disclosed in ‘211 comprises ofspironolactone, and an aqueous homogenising effective amount of a material selected from the group consisting of (i) sodium carboxymethylcellulose, and (ii) a mixture of methylcellulose and a dimethyl polysiloxane polymer.

US9757394 discloses pharmaceutical suspension comprising of (a) spironolactone, (b) a xanthan gum, (c) simethicone as an anti-foaming agent, (d) sorbic acid and potassium sorbate as preservative, (f) a dispersing agent, (g) a sweetening agent, (h) a flavouring agent, (i) optionally a buffer to maintain the pH of the pharmaceutical composition within a range described herein and (j) a sufficient amount of a water vehicle.

However, for suspensions dosage form active ingredient’s particle size distribution, viscosity of excipients being used in product composition, manufacturing process, sedimentation of dispersed phase, phase separation, cake formation and agglomeration of active ingredients during storage and nonuniformity of dose are major risks.

There are number of challenges surrounding the formulation and development of liquid dosage forms such as stability, solubility and taste. While using a cosolvent, it may cause stability and bitter taste problems besides providing solubility. Further, active pharmaceutical agents in liquid dosage forms are more susceptible to chemical and physical instability than the solid state. The inventors of the present invention have developed a novel oral solution of spironolactone which is stable and overcomes the challenges associated with liquid dosage forms, especially solution. Object of the Invention:

The main object of the present invention is to provide a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients.

Another object of the present invention is to provide a stable oral solution of spironolactone as a potassium sparing diuretic, providing flexibility in dosing regimen for patients who need special doses of the drug, specifically in paediatrics, geriatrics along with institutionalized patients and patients with complications for swallowing.

Another object of the present invention is to provide a stable oral solution of spironolactone with improved taste having high patient compliance.

Another object of the present invention is to provide a process to prepare a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients.

Another object of the present invention is to provide a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients for the treatment of fluid build-up due to heart failure, liver scarring or kidney disease.

Another object of the present invention is to provide a stable oral solution of spironolactone with improved bioavailability.

Summary of the Invention:

In one aspect, the present relates to a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients. In one aspect, the present invention relates to a process to prepare a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients.

In one aspect, the present invention relates to a method of prevention or treatment of fluid build-up due to heart failure, liver scarring or kidney disease by administering a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients.

In one aspect, the present relates to a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients, packaged in glass containers.

Description of the Invention:

Unless otherwise defined, all terms used in disclosing the invention, including technical and scientific terms, have the meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It should be understood that the detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the invention. Numerous changes, substitutions, and modifications may be made without departing from the scope of the present invention.

According to one aspect, the present relates to a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients.

The present invention relates to a stable oral solution comprising spironolactone. Specifically, the present invention relates to an oral solution of spironolactone or its pharmaceutically acceptable salts, solvates, hydrates, polymorphs, stereoisomers, esters, prodrugs, enantiomers, complexes and their metabolites thereof.

Spironolactone is reported to be poorly soluble in all aqueous media. Poor aqueous solubility of spironolactone (0.02 mg/ml) is a major hurdle in the development of a liquid solution formulation of spironolactone.

Solubility studies were conducted to identify a solvent system that supports to a unit dose concentration.

It was determined that a concentration of (5mg/ml) of spironolactone in an oral solution adequately supports a desired dosage range of 25 mg to 75mg. In one embodiment, the solubility of spironolactone in solvent system is selected from the group ofa lipid-based carrier excipient comprising oil or a mixture of oils.

In one embodiment, the solubility of spironolactone in solvent system is selected from oil, derived from plants. Solubility of spironolactone in different triglycerides was determined as per details given below: In one embodiment, the solubility of spironolactone in solvent system is selected from the group of a plant-derived oil consisting of: almond oil, rapeseed oil, cod liver oil, com oil, cottonseed oil, flaxseed oil, seed oil is described. Grape, peanut oil, safflower oil, sesame oil, soybean oil, sunflower oil, walnut oil, coconut oil or palm kernel oil.

Vegetable oil comprising fractionated coconut oil and palm kernel oil is described.

In one embodiment, the solubility of spironolactone in solvent system of short, medium or long chain triglycerides can be at least 2mg/ml to 25mg/ml.

In one embodiment, the solubility of spironolactone in solvent system of medium chain triglyceride can be at least 2mg/ml to 25mg/ml.

In one embodiment, the solubility of spironolactone in fractionated coconut oil can be at least 2mg/ml to 25mg/ml.

In one embodiment, the solubility of spironolactone in medium chain triglyceride is upto 25mg/ml.

In one embodiment, the solubility of spironolactone in fractionated coconut oil is 10 mg/ml.

In one embodiment, the solubility of spironolactone in fractionated coconut oil is

8 mg/ml to 14 mg/ml.

In one embodiment, the solubility of spironolactone in fractionated coconut oil is

9 mg/ml to 11 mg/ml.

In one embodiment, the solubility of spironolactone in palm kernel oil can be at least 2mg/ml to 25mg/ml.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, short chain triglycerides, and pharmaceutically acceptable excipients. In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, medium chain triglycerides, and pharmaceutically acceptable excipients.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, long chain triglycerides, and pharmaceutically acceptable excipients.

In one embodiment, the present invention relates to a stable oral non-aqueous solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides, stabilizing agent and pharmaceutically acceptable excipients.

According to one embodiment, the present invention relates to a stable oral solution comprising spironolactone, medium chain triglycerides, stabilizing agent and pharmaceutically acceptable excipients.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, medium chain triglycerides of use in the practice of the invention have carbon-chain lengths of 6-12 and, preferably, the composition medium comprises at least 95% triglycerides having a carbon-chain length selected from 8-10.

Medium-chain triglycerides are obtained from the oil extracted from the hard, dried fraction of the endosperm of Cocos nucifera L. or from the dried endosperm of Elaeisguineensis Jacq. They consist of a mixture of triglycerides of saturated fatty acids, mainly of caprylic acid (CsHieCh) and of capric acid (C10H20O2). They contain not less than 95 percent of saturated fatty acids having 8 to 10 carbon atoms. The substance is a clear solution.

It is described that the oil includes at least one or a combination of fatty acids selected from the group consisting of caprylic / capric triglycerides (eg Miglyol® 810, 812 and 812N), triglycerides45 capric / capric / linoleic (for example, Miglyol® 818), triglyceric of capric / capric / myriatic / stearic fatty acids (for example, Softisan® 378), triglycerides of caprylic / capric / succinic fatty acids (for example, Miglyol® 829), capric / capric triglycerides with stearalkonium benonite and propylene carbonate (for example, Migyol® Gel T), capric / capric triglycerides with stearalconium hectorite and propylene carbonate (for example, Migyol® Gel B).

Preferably, said oil according to the invention is conveniently provided as Miglyol.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, fractionated coconut oil, stabilizing agent and pharmaceutically acceptable excipients.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, miglyol, stabilizing agent and pharmaceutically acceptable excipients.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, medium chain triglyceride, stabilizing agent and pharmaceutically acceptable excipients, wherein the solubility of spironolactone in medium chain triglycerides up to25mg/ml.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, miglyol, stabilizing agent and pharmaceutically acceptable excipients, wherein the solubility of spironolactone in miglyol is up to 25mg/ml.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, miglyol, butylated hydroxyl anisole and pharmaceutically acceptable excipients, wherein the solubility of spironolactone in miglyol is lOmg/ml.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, medium chain triglyceride stabilizing agent and pharmaceutically acceptable excipients, wherein the solubility of spironolactone in miglyol is 9mg/ml to 11 mg/ml.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, medium chain triglyceride stabilizing agent and pharmaceutically acceptable excipients, wherein the solubility of spironolactone in miglyol is 5mg/ml.

In one embodiment, the present relates to a stable oral solution comprising spironolactone, palm kernel oil, stabilizing agent and pharmaceutically acceptable excipients.

In one embodiment, the present relates to a stable oral solution comprising:

0.1% to 10% spironolactone,

10% to 99.95% solvent system selected from the group of short, medium or long chain triglycerides,

0.0001% to 0.5% stabilizing agent and,

0.001% to 5% flavouring agent.

In one embodiment, the present relates to a stable oral solution comprising:

0.1% to 10% spironolactone,

10% to 99.90% medium chain triglyceride,

0.0001% to 0.5% stabilizing agent and,

0.001% to 5% flavouring agent.

In one embodiment, the present relates to a stable oral solution comprising:

0.1% to 10% spironolactone,

10% to 99.90% fractionated coconut oil,

0.0001% to 0.5% butyratehydroxyl anisole and,

0.001% to 5% peppermint oil.

In one embodiment, the present relates to a stable oral solution comprising: 0.1% to 10% spironolactone, 10% to 99.90% miglyol, 0.0001% to 0.5% butylated hydroxy anisole and,

0.001% to 5 % peppermint oil, wherein the solubility of spironolactone in miglyol is 10 mg/ml.

In one embodiment, the present invention relates to a stable oral solution comprising: a) a therapeutically effective amount of spironolactone or a pharmaceutically acceptable salt or solvate thereof. b) a solvent system selected from group consisting of short, medium or long chain triglycerides.

The present invention further contains pharmaceutically acceptable excipients selected from the group comprising of stabilizing agent, flavouring agent used individually or in combination thereof.

In one embodiment, the present invention relates to a stable oral solution comprising: c) a therapeutically effective amount of spironolactone or a pharmaceutically acceptable salt or solvate thereof. d) a solvent system selected from group consisting of short, medium or long chain triglycerides. e) stabilizing agent and, f) pharmaceutically acceptable excipients selected from the group consisting of flavouring agent and the like.

In one embodiment, the present invention relates to a stable oral solution comprising: a) a therapeutically effective amount of spironolactone or a pharmaceutically acceptable salt or solvate thereof. b) a solvent system selected from group consisting of short, medium or long chain triglycerides and, c) pharmaceutically acceptable excipients selected from the group comprising of stabilizing agent, flavouring agent and the like. In one embodiment, the present invention relates to a stable oral solution comprising spironolactone or its pharmaceutically acceptable salts, solvates, hydrates, polymorphs, stereoisomers, esters, prodrugs, enantiomers, complexes and metabolites thereof.

The pharmaceutically acceptable excipients contained in the oral solution of present invention include stabilizers, flavouring agents and other conventional agents that may be typically used in formulating oral solution.

Stabilizing agents that can be used in the oral solution of the present invention include, but are not limited to sodium sulphate, sodium metabisulphite, sodium formaldehyde, sulphoxylate, ascorbic acid, butylated hydroxytoluene (BHT), butylated hydroxy anisole (BHA), propyl gallate, sodium citrate, citric acid and/or combinations thereof.

Flavouring agents that can be used in the oral solution of the present invention include, but not limited to peppermint, grape, orange, lime oil, lemon, pineapple, berries, lavender, dill, spearmint, eucalyptus, ethyl vanillin, fruit flavour, caramel flavour and/or combinations thereof.

Long chain triglycerides that can be used in the oral solution of present invention include, but not limited to almond oil, rapeseed oil, cod liver oil, com oil, cottonseed oil, flaxseed oil, seed oil, grape, peanut oil, safflower oil, sesame oil, soybean oil, sunflower oil, walnut oil and /or combinations thereof.

Medium chain triglycerides that can be used in the oral solution of present invention include, but not limited to fractionated coconut oil, palm kernel oil, fatty acids selected from the group consisting of caprylic / capric triglycerides (eg Miglyol® 810, 812 and 812N), triglycerides45 capric / capric / linoleic (for example, Miglyol® 818), triglyceric of capric / capric / myriatic / stearic fatty acids (for example, Softisan® 378), triglycerides of caprylic / capric / succinic fatty acids (for example, Miglyol® 829), capric / capric triglycerides with stearalkonium benonite and propylene carbonate (for example, Migyol® Gel T), capric / capric triglycerides with stearalconium hectorite and propylene carbonate (for example, Migyol® Gel B) and/or combinations thereof.

Short chain triglycerides that can be used in the oral solution of present invention include, but not limited to acetate, propionate, butyrate and/or combinations thereof.

The concentration of spironolactone is between 0.1 to 10 % (w/v), or any specific value within the said range.

According to one aspect, the present invention relates to a process to prepare a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients.

In one embodiment, the present invention relates to a process to prepare a stable oral solution comprising spironolactone, comprises of following steps: a) Preparation of a vehicle by dissolving stabilizing agent, flavouring agent in medium chain triglyceride under continuous stirring. b) Mixing spironolactone in the said vehicle of step 1 under stirring to form aclear and homogenous solution. c) Volume adjusted with medium chain triglycerides. d) Optionally, filtration of said step c) solution using suitable filter.

In one embodiment, the present invention relates to a process to prepare a stable oral solution comprising spironolactone, comprises of following steps: a) Preparation of a vehicle by dissolving stabilizing agent, flavouring agent in fractionated coconut oil under continuous stirring. b) Mixing spironolactone in the said vehicle of step 1 under stirring to form a clear and homogenous solution. c) Volume adjusted with fractionated coconut oil. d) Optionally, filtration of said step c) solution using suitable filter. In one embodiment, the present invention relates to a process to prepare a stable oral solution comprising spironolactone, comprises of following steps: a) Preparation of a vehicle by dissolving butylated hydroxyl anisole, peppermint flavour in caprylic / capric triglyceride (miglyol) under continuous stirring. b) Mixing spironolactone in the said vehicle of step 1 under stirring to form a clear and homogenous solution. c) Volume adjusted with miglyol. d) Optionally, filtration of said step c) solution using suitable filter.

According to another aspect, the present invention relates to a method of prevention or treatmentof fluid build-up due to heart failure, liver scarring or kidney disease by administering a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients.

In one embodiment, the present invention relates to a method of prevention or treatment of fluid build-up due to heart failure, liver scarring or kidney disease by administering a stable oral solution comprising spironolactone, short chain triglyceride and pharmaceutically acceptable excipients.

In one embodiment, the present invention relates to a method of prevention or treatment of fluid build-up due to heart failure, liver scarring or kidney disease by administering a stable oral solution comprising spironolactone, medium chain triglyceride and pharmaceutically acceptable excipients.

In one embodiment, the present invention relates to a method of prevention or treatment of fluid build-up due to heart failure, liver scarring or kidney disease by administering a stable oral solution comprising spironolactone, long chain triglyceride and pharmaceutically acceptable excipients.

In one embodiment, the present invention relates to a method of prevention or treatment of fluid build-up due to heart failure, liver scarring or kidney disease by administering a stable oral solution comprising spironolactone, fractionated coconut oil and pharmaceutically acceptable excipients.

In one embodiment, the present invention relates to a method of prevention or treatment of fluid build-up due to heart failure, liver scarring or kidney disease by administering a stable oral solution comprising spironolactone, palm kernel oil and pharmaceutically acceptable excipients.

In one embodiment, the present invention relates to a method of prevention or treatment of fluid build-up due to heart failure, liver scarring or kidney disease by administering a stable oral solution comprising spironolactone, miglyol and pharmaceutically acceptable excipients.

According to another aspect, the present invention relates to a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients, packaged in bottle.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients, packaged in amber glass bottle containers.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients, packaged in flexible plastic bottle containers.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients, packaged in High Density Polyethylene bottle containers. In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients, packaged in Polyethylene Terephthalate bottle containers.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients, packaged in Polypropylene bottle containers.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, solvent system selected from the group of short, medium or long chain triglycerides and pharmaceutically acceptable excipients, packaged in 50 ml to 300 ml bottle containers.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, solvent system selected from group of medium chain triglycerides and pharmaceutically acceptable excipients with good oral palatability of said solution when tested cautiously in mouth by group of persons involved in formulation development of said dosage form.

In one embodiment, the present invention relates to a stable oral solution comprising spironolactone, solvent system selected from group of medium chain triglycerides and pharmaceutically acceptable excipients, where said oral solution can be administered: for Heart Failure: Initiate treatment at 20 mg once daily. for Hypertension: Initiate treatment at 20 to 75 mg daily in either single or divided doses for Edema associated with Hepatic Cirrhosis: Initiate therapy in a hospital setting and titrate slowly. The initial recommended daily dose is 75 mg in either single or divided dose.

Accordingly, the following examples are intended to illustrate the present invention, but are not intended to limit the scope of the invention. Example 1

Procedure: a) Medium Chain Triglyceride (Miglyol 8 ION) was dispensed into a main mixing vessel. b) Butylated Hydroxy Anisole and Peppermint oil were added to the above solution. c) Spironolactone was added under continuous stirring to said mixing vessel to form clear homogeneous solution. d) The volume was adjusted by adding Miglyol 8 ION. e) Optionally, filtration of said step d) solution using suitable filter.

Example 2

Procedure: a) Medium Chain Triglyceride (Miglyol 812) was dispensed into a main mixing vessel. b) Butylated Hydroxy Anisole and Peppermint oil were added to the above solution. c) Spironolactone was added under continuous stirring to said mixing vessel to form clear homogeneous solution. d) The volume was adjusted by adding Miglyol 812. e) Optionally, filtration of said step d) solution using suitable filter. Example 3

Procedure: a) Medium Chain Triglyceride (Palm kernel oil) was dispensed into a main mixing vessel. b) Butylated Hydroxy Anisole and Peppermint oil were added to the above solution. c) Spironolactone was added under continuous stirring to said mixing vessel to form clear homogeneous solution. d) The volume was adjusted by adding Palm kernel oil. e) Optionally, filtration of said step d) solution using suitable filter.

Example 4

Procedure: a) Long Chain Triglyceride (Soybean Oil) was dispensed into a main mixing vessel. b) Butylated Hydroxy Anisole and Orange oil were added to the above solution. c) Spironolactone was added under continuous stirring to said mixing vessel to form clear homogeneous solution. d) The volume was adjusted by adding Soybean oil. e) Optionally, filtration of said step d) solution using suitable filter. Example 5

Procedure: a) Medium Chain Triglyceride (Miglyol 8 ION) and Short Chain Triglycerides (Propionate) were dispensed into a main mixing vessel. b) Butylated Hydroxy Anisole and Pineapple oil were added to the above solution. c) Spironolactone was added under continuous stirring to said mixing vessel to form clear homogeneous solution. d) The volume was adjusted by adding Soybean oil. e) Optionally, filtration of said step d solution using suitable filter.

Stability Data of the Example 1 Composition. Observation:

1. Spironolactone solution manufactured with said composition was observed to be stable for at least 6 months at 25°C/60% RH and 40°C/75% RH.

2. No change in description of Spironolactone solution observed for at least 6 months at 25°C/60% RH and 40°C/75% RH.

3. No significant change in viscosity and specific gravity of Spironolactone solution observed for at least 6 months at 25°C/60% RH and 40°C/75% RH.

4. No significant change in related substances of Spironolactone solution observed for at least 6 months at 25°C/60% RH and 40°C/75% RH.

5. Impurity A level in Spironolactone solution was observed to be much below specified limits.

Conclusion:

Spironolactone oral solution observed to be stable at 25°C/60% RH and 40°C/75% RH for at least 6 months.